3143 lines
170 KiB
Diff
3143 lines
170 KiB
Diff
From: Tom Zanussi <tom.zanussi@linux.intel.com>
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Date: Wed, 6 Dec 2017 16:37:42 -0600
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Subject: [PATCH 01/37] tracing: Move hist trigger Documentation to
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histogram.txt
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Origin: https://www.kernel.org/pub/linux/kernel/projects/rt/4.14/older/patches-4.14.6-rt7.tar.xz
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The hist trigger Documentation takes up a large part of events.txt -
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since it will be getting even larger, move it to a separate file.
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Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
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Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
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---
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Documentation/trace/events.txt | 1548 -------------------------------------
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Documentation/trace/histogram.txt | 1568 ++++++++++++++++++++++++++++++++++++++
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2 files changed, 1569 insertions(+), 1547 deletions(-)
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create mode 100644 Documentation/trace/histogram.txt
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--- a/Documentation/trace/events.txt
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+++ b/Documentation/trace/events.txt
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@@ -517,1550 +517,4 @@ triggers (you have to use '!' for each o
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totals derived from one or more trace event format fields and/or
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event counts (hitcount).
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- The format of a hist trigger is as follows:
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-
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- hist:keys=<field1[,field2,...]>[:values=<field1[,field2,...]>]
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- [:sort=<field1[,field2,...]>][:size=#entries][:pause][:continue]
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- [:clear][:name=histname1] [if <filter>]
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-
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- When a matching event is hit, an entry is added to a hash table
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- using the key(s) and value(s) named. Keys and values correspond to
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- fields in the event's format description. Values must correspond to
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- numeric fields - on an event hit, the value(s) will be added to a
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- sum kept for that field. The special string 'hitcount' can be used
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- in place of an explicit value field - this is simply a count of
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- event hits. If 'values' isn't specified, an implicit 'hitcount'
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- value will be automatically created and used as the only value.
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- Keys can be any field, or the special string 'stacktrace', which
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- will use the event's kernel stacktrace as the key. The keywords
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- 'keys' or 'key' can be used to specify keys, and the keywords
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- 'values', 'vals', or 'val' can be used to specify values. Compound
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- keys consisting of up to two fields can be specified by the 'keys'
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- keyword. Hashing a compound key produces a unique entry in the
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- table for each unique combination of component keys, and can be
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- useful for providing more fine-grained summaries of event data.
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- Additionally, sort keys consisting of up to two fields can be
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- specified by the 'sort' keyword. If more than one field is
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- specified, the result will be a 'sort within a sort': the first key
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- is taken to be the primary sort key and the second the secondary
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- key. If a hist trigger is given a name using the 'name' parameter,
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- its histogram data will be shared with other triggers of the same
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- name, and trigger hits will update this common data. Only triggers
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- with 'compatible' fields can be combined in this way; triggers are
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- 'compatible' if the fields named in the trigger share the same
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- number and type of fields and those fields also have the same names.
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- Note that any two events always share the compatible 'hitcount' and
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- 'stacktrace' fields and can therefore be combined using those
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- fields, however pointless that may be.
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-
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- 'hist' triggers add a 'hist' file to each event's subdirectory.
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- Reading the 'hist' file for the event will dump the hash table in
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- its entirety to stdout. If there are multiple hist triggers
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- attached to an event, there will be a table for each trigger in the
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- output. The table displayed for a named trigger will be the same as
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- any other instance having the same name. Each printed hash table
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- entry is a simple list of the keys and values comprising the entry;
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- keys are printed first and are delineated by curly braces, and are
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- followed by the set of value fields for the entry. By default,
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- numeric fields are displayed as base-10 integers. This can be
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- modified by appending any of the following modifiers to the field
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- name:
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-
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- .hex display a number as a hex value
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- .sym display an address as a symbol
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- .sym-offset display an address as a symbol and offset
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- .syscall display a syscall id as a system call name
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- .execname display a common_pid as a program name
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-
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- Note that in general the semantics of a given field aren't
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- interpreted when applying a modifier to it, but there are some
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- restrictions to be aware of in this regard:
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-
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- - only the 'hex' modifier can be used for values (because values
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- are essentially sums, and the other modifiers don't make sense
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- in that context).
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- - the 'execname' modifier can only be used on a 'common_pid'. The
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- reason for this is that the execname is simply the 'comm' value
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- saved for the 'current' process when an event was triggered,
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- which is the same as the common_pid value saved by the event
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- tracing code. Trying to apply that comm value to other pid
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- values wouldn't be correct, and typically events that care save
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- pid-specific comm fields in the event itself.
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-
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- A typical usage scenario would be the following to enable a hist
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- trigger, read its current contents, and then turn it off:
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-
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- # echo 'hist:keys=skbaddr.hex:vals=len' > \
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- /sys/kernel/debug/tracing/events/net/netif_rx/trigger
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-
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- # cat /sys/kernel/debug/tracing/events/net/netif_rx/hist
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-
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- # echo '!hist:keys=skbaddr.hex:vals=len' > \
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- /sys/kernel/debug/tracing/events/net/netif_rx/trigger
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-
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- The trigger file itself can be read to show the details of the
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- currently attached hist trigger. This information is also displayed
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- at the top of the 'hist' file when read.
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-
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- By default, the size of the hash table is 2048 entries. The 'size'
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- parameter can be used to specify more or fewer than that. The units
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- are in terms of hashtable entries - if a run uses more entries than
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- specified, the results will show the number of 'drops', the number
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- of hits that were ignored. The size should be a power of 2 between
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- 128 and 131072 (any non- power-of-2 number specified will be rounded
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- up).
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-
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- The 'sort' parameter can be used to specify a value field to sort
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- on. The default if unspecified is 'hitcount' and the default sort
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- order is 'ascending'. To sort in the opposite direction, append
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- .descending' to the sort key.
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-
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- The 'pause' parameter can be used to pause an existing hist trigger
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- or to start a hist trigger but not log any events until told to do
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- so. 'continue' or 'cont' can be used to start or restart a paused
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- hist trigger.
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-
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- The 'clear' parameter will clear the contents of a running hist
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- trigger and leave its current paused/active state.
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-
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- Note that the 'pause', 'cont', and 'clear' parameters should be
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- applied using 'append' shell operator ('>>') if applied to an
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- existing trigger, rather than via the '>' operator, which will cause
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- the trigger to be removed through truncation.
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-
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-- enable_hist/disable_hist
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-
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- The enable_hist and disable_hist triggers can be used to have one
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- event conditionally start and stop another event's already-attached
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- hist trigger. Any number of enable_hist and disable_hist triggers
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- can be attached to a given event, allowing that event to kick off
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- and stop aggregations on a host of other events.
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-
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- The format is very similar to the enable/disable_event triggers:
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-
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- enable_hist:<system>:<event>[:count]
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- disable_hist:<system>:<event>[:count]
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-
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- Instead of enabling or disabling the tracing of the target event
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- into the trace buffer as the enable/disable_event triggers do, the
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- enable/disable_hist triggers enable or disable the aggregation of
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- the target event into a hash table.
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-
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- A typical usage scenario for the enable_hist/disable_hist triggers
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- would be to first set up a paused hist trigger on some event,
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- followed by an enable_hist/disable_hist pair that turns the hist
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- aggregation on and off when conditions of interest are hit:
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-
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- # echo 'hist:keys=skbaddr.hex:vals=len:pause' > \
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- /sys/kernel/debug/tracing/events/net/netif_receive_skb/trigger
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-
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- # echo 'enable_hist:net:netif_receive_skb if filename==/usr/bin/wget' > \
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- /sys/kernel/debug/tracing/events/sched/sched_process_exec/trigger
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-
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- # echo 'disable_hist:net:netif_receive_skb if comm==wget' > \
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- /sys/kernel/debug/tracing/events/sched/sched_process_exit/trigger
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-
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- The above sets up an initially paused hist trigger which is unpaused
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- and starts aggregating events when a given program is executed, and
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- which stops aggregating when the process exits and the hist trigger
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- is paused again.
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-
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- The examples below provide a more concrete illustration of the
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- concepts and typical usage patterns discussed above.
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-
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-
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-6.2 'hist' trigger examples
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----------------------------
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-
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- The first set of examples creates aggregations using the kmalloc
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- event. The fields that can be used for the hist trigger are listed
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- in the kmalloc event's format file:
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-
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- # cat /sys/kernel/debug/tracing/events/kmem/kmalloc/format
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- name: kmalloc
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- ID: 374
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- format:
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- field:unsigned short common_type; offset:0; size:2; signed:0;
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- field:unsigned char common_flags; offset:2; size:1; signed:0;
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- field:unsigned char common_preempt_count; offset:3; size:1; signed:0;
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- field:int common_pid; offset:4; size:4; signed:1;
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-
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- field:unsigned long call_site; offset:8; size:8; signed:0;
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- field:const void * ptr; offset:16; size:8; signed:0;
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- field:size_t bytes_req; offset:24; size:8; signed:0;
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- field:size_t bytes_alloc; offset:32; size:8; signed:0;
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- field:gfp_t gfp_flags; offset:40; size:4; signed:0;
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-
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- We'll start by creating a hist trigger that generates a simple table
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- that lists the total number of bytes requested for each function in
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- the kernel that made one or more calls to kmalloc:
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-
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- # echo 'hist:key=call_site:val=bytes_req' > \
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- /sys/kernel/debug/tracing/events/kmem/kmalloc/trigger
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-
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- This tells the tracing system to create a 'hist' trigger using the
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- call_site field of the kmalloc event as the key for the table, which
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- just means that each unique call_site address will have an entry
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- created for it in the table. The 'val=bytes_req' parameter tells
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- the hist trigger that for each unique entry (call_site) in the
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- table, it should keep a running total of the number of bytes
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- requested by that call_site.
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-
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- We'll let it run for awhile and then dump the contents of the 'hist'
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- file in the kmalloc event's subdirectory (for readability, a number
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- of entries have been omitted):
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-
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- # cat /sys/kernel/debug/tracing/events/kmem/kmalloc/hist
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- # trigger info: hist:keys=call_site:vals=bytes_req:sort=hitcount:size=2048 [active]
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-
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- { call_site: 18446744072106379007 } hitcount: 1 bytes_req: 176
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- { call_site: 18446744071579557049 } hitcount: 1 bytes_req: 1024
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- { call_site: 18446744071580608289 } hitcount: 1 bytes_req: 16384
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- { call_site: 18446744071581827654 } hitcount: 1 bytes_req: 24
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- { call_site: 18446744071580700980 } hitcount: 1 bytes_req: 8
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- { call_site: 18446744071579359876 } hitcount: 1 bytes_req: 152
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- { call_site: 18446744071580795365 } hitcount: 3 bytes_req: 144
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- { call_site: 18446744071581303129 } hitcount: 3 bytes_req: 144
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- { call_site: 18446744071580713234 } hitcount: 4 bytes_req: 2560
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- { call_site: 18446744071580933750 } hitcount: 4 bytes_req: 736
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- .
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- .
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- .
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- { call_site: 18446744072106047046 } hitcount: 69 bytes_req: 5576
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- { call_site: 18446744071582116407 } hitcount: 73 bytes_req: 2336
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- { call_site: 18446744072106054684 } hitcount: 136 bytes_req: 140504
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- { call_site: 18446744072106224230 } hitcount: 136 bytes_req: 19584
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- { call_site: 18446744072106078074 } hitcount: 153 bytes_req: 2448
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- { call_site: 18446744072106062406 } hitcount: 153 bytes_req: 36720
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- { call_site: 18446744071582507929 } hitcount: 153 bytes_req: 37088
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- { call_site: 18446744072102520590 } hitcount: 273 bytes_req: 10920
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- { call_site: 18446744071582143559 } hitcount: 358 bytes_req: 716
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- { call_site: 18446744072106465852 } hitcount: 417 bytes_req: 56712
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- { call_site: 18446744072102523378 } hitcount: 485 bytes_req: 27160
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- { call_site: 18446744072099568646 } hitcount: 1676 bytes_req: 33520
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-
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- Totals:
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- Hits: 4610
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- Entries: 45
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- Dropped: 0
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-
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- The output displays a line for each entry, beginning with the key
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- specified in the trigger, followed by the value(s) also specified in
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- the trigger. At the beginning of the output is a line that displays
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- the trigger info, which can also be displayed by reading the
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- 'trigger' file:
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-
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- # cat /sys/kernel/debug/tracing/events/kmem/kmalloc/trigger
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- hist:keys=call_site:vals=bytes_req:sort=hitcount:size=2048 [active]
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-
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- At the end of the output are a few lines that display the overall
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- totals for the run. The 'Hits' field shows the total number of
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- times the event trigger was hit, the 'Entries' field shows the total
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- number of used entries in the hash table, and the 'Dropped' field
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- shows the number of hits that were dropped because the number of
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- used entries for the run exceeded the maximum number of entries
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- allowed for the table (normally 0, but if not a hint that you may
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- want to increase the size of the table using the 'size' parameter).
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-
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- Notice in the above output that there's an extra field, 'hitcount',
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- which wasn't specified in the trigger. Also notice that in the
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- trigger info output, there's a parameter, 'sort=hitcount', which
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- wasn't specified in the trigger either. The reason for that is that
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- every trigger implicitly keeps a count of the total number of hits
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- attributed to a given entry, called the 'hitcount'. That hitcount
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- information is explicitly displayed in the output, and in the
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- absence of a user-specified sort parameter, is used as the default
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- sort field.
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-
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- The value 'hitcount' can be used in place of an explicit value in
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- the 'values' parameter if you don't really need to have any
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- particular field summed and are mainly interested in hit
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- frequencies.
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-
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- To turn the hist trigger off, simply call up the trigger in the
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- command history and re-execute it with a '!' prepended:
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-
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- # echo '!hist:key=call_site:val=bytes_req' > \
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- /sys/kernel/debug/tracing/events/kmem/kmalloc/trigger
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-
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- Finally, notice that the call_site as displayed in the output above
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- isn't really very useful. It's an address, but normally addresses
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- are displayed in hex. To have a numeric field displayed as a hex
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- value, simply append '.hex' to the field name in the trigger:
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-
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- # echo 'hist:key=call_site.hex:val=bytes_req' > \
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- /sys/kernel/debug/tracing/events/kmem/kmalloc/trigger
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-
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- # cat /sys/kernel/debug/tracing/events/kmem/kmalloc/hist
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- # trigger info: hist:keys=call_site.hex:vals=bytes_req:sort=hitcount:size=2048 [active]
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-
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- { call_site: ffffffffa026b291 } hitcount: 1 bytes_req: 433
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- { call_site: ffffffffa07186ff } hitcount: 1 bytes_req: 176
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- { call_site: ffffffff811ae721 } hitcount: 1 bytes_req: 16384
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- { call_site: ffffffff811c5134 } hitcount: 1 bytes_req: 8
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- { call_site: ffffffffa04a9ebb } hitcount: 1 bytes_req: 511
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- { call_site: ffffffff8122e0a6 } hitcount: 1 bytes_req: 12
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- { call_site: ffffffff8107da84 } hitcount: 1 bytes_req: 152
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- { call_site: ffffffff812d8246 } hitcount: 1 bytes_req: 24
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- { call_site: ffffffff811dc1e5 } hitcount: 3 bytes_req: 144
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- { call_site: ffffffffa02515e8 } hitcount: 3 bytes_req: 648
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- { call_site: ffffffff81258159 } hitcount: 3 bytes_req: 144
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- { call_site: ffffffff811c80f4 } hitcount: 4 bytes_req: 544
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- .
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- .
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- .
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- { call_site: ffffffffa06c7646 } hitcount: 106 bytes_req: 8024
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- { call_site: ffffffffa06cb246 } hitcount: 132 bytes_req: 31680
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- { call_site: ffffffffa06cef7a } hitcount: 132 bytes_req: 2112
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- { call_site: ffffffff8137e399 } hitcount: 132 bytes_req: 23232
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- { call_site: ffffffffa06c941c } hitcount: 185 bytes_req: 171360
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- { call_site: ffffffffa06f2a66 } hitcount: 185 bytes_req: 26640
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- { call_site: ffffffffa036a70e } hitcount: 265 bytes_req: 10600
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- { call_site: ffffffff81325447 } hitcount: 292 bytes_req: 584
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- { call_site: ffffffffa072da3c } hitcount: 446 bytes_req: 60656
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- { call_site: ffffffffa036b1f2 } hitcount: 526 bytes_req: 29456
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- { call_site: ffffffffa0099c06 } hitcount: 1780 bytes_req: 35600
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-
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- Totals:
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- Hits: 4775
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- Entries: 46
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- Dropped: 0
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-
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- Even that's only marginally more useful - while hex values do look
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- more like addresses, what users are typically more interested in
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- when looking at text addresses are the corresponding symbols
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- instead. To have an address displayed as symbolic value instead,
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- simply append '.sym' or '.sym-offset' to the field name in the
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- trigger:
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-
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- # echo 'hist:key=call_site.sym:val=bytes_req' > \
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- /sys/kernel/debug/tracing/events/kmem/kmalloc/trigger
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-
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- # cat /sys/kernel/debug/tracing/events/kmem/kmalloc/hist
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- # trigger info: hist:keys=call_site.sym:vals=bytes_req:sort=hitcount:size=2048 [active]
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-
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- { call_site: [ffffffff810adcb9] syslog_print_all } hitcount: 1 bytes_req: 1024
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- { call_site: [ffffffff8154bc62] usb_control_msg } hitcount: 1 bytes_req: 8
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- { call_site: [ffffffffa00bf6fe] hidraw_send_report [hid] } hitcount: 1 bytes_req: 7
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- { call_site: [ffffffff8154acbe] usb_alloc_urb } hitcount: 1 bytes_req: 192
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- { call_site: [ffffffffa00bf1ca] hidraw_report_event [hid] } hitcount: 1 bytes_req: 7
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- { call_site: [ffffffff811e3a25] __seq_open_private } hitcount: 1 bytes_req: 40
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- { call_site: [ffffffff8109524a] alloc_fair_sched_group } hitcount: 2 bytes_req: 128
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- { call_site: [ffffffff811febd5] fsnotify_alloc_group } hitcount: 2 bytes_req: 528
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- { call_site: [ffffffff81440f58] __tty_buffer_request_room } hitcount: 2 bytes_req: 2624
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- { call_site: [ffffffff81200ba6] inotify_new_group } hitcount: 2 bytes_req: 96
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- { call_site: [ffffffffa05e19af] ieee80211_start_tx_ba_session [mac80211] } hitcount: 2 bytes_req: 464
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- { call_site: [ffffffff81672406] tcp_get_metrics } hitcount: 2 bytes_req: 304
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- { call_site: [ffffffff81097ec2] alloc_rt_sched_group } hitcount: 2 bytes_req: 128
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- { call_site: [ffffffff81089b05] sched_create_group } hitcount: 2 bytes_req: 1424
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- .
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- .
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- .
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- { call_site: [ffffffffa04a580c] intel_crtc_page_flip [i915] } hitcount: 1185 bytes_req: 123240
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- { call_site: [ffffffffa0287592] drm_mode_page_flip_ioctl [drm] } hitcount: 1185 bytes_req: 104280
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- { call_site: [ffffffffa04c4a3c] intel_plane_duplicate_state [i915] } hitcount: 1402 bytes_req: 190672
|
|
- { call_site: [ffffffff812891ca] ext4_find_extent } hitcount: 1518 bytes_req: 146208
|
|
- { call_site: [ffffffffa029070e] drm_vma_node_allow [drm] } hitcount: 1746 bytes_req: 69840
|
|
- { call_site: [ffffffffa045e7c4] i915_gem_do_execbuffer.isra.23 [i915] } hitcount: 2021 bytes_req: 792312
|
|
- { call_site: [ffffffffa02911f2] drm_modeset_lock_crtc [drm] } hitcount: 2592 bytes_req: 145152
|
|
- { call_site: [ffffffffa0489a66] intel_ring_begin [i915] } hitcount: 2629 bytes_req: 378576
|
|
- { call_site: [ffffffffa046041c] i915_gem_execbuffer2 [i915] } hitcount: 2629 bytes_req: 3783248
|
|
- { call_site: [ffffffff81325607] apparmor_file_alloc_security } hitcount: 5192 bytes_req: 10384
|
|
- { call_site: [ffffffffa00b7c06] hid_report_raw_event [hid] } hitcount: 5529 bytes_req: 110584
|
|
- { call_site: [ffffffff8131ebf7] aa_alloc_task_context } hitcount: 21943 bytes_req: 702176
|
|
- { call_site: [ffffffff8125847d] ext4_htree_store_dirent } hitcount: 55759 bytes_req: 5074265
|
|
-
|
|
- Totals:
|
|
- Hits: 109928
|
|
- Entries: 71
|
|
- Dropped: 0
|
|
-
|
|
- Because the default sort key above is 'hitcount', the above shows a
|
|
- the list of call_sites by increasing hitcount, so that at the bottom
|
|
- we see the functions that made the most kmalloc calls during the
|
|
- run. If instead we we wanted to see the top kmalloc callers in
|
|
- terms of the number of bytes requested rather than the number of
|
|
- calls, and we wanted the top caller to appear at the top, we can use
|
|
- the 'sort' parameter, along with the 'descending' modifier:
|
|
-
|
|
- # echo 'hist:key=call_site.sym:val=bytes_req:sort=bytes_req.descending' > \
|
|
- /sys/kernel/debug/tracing/events/kmem/kmalloc/trigger
|
|
-
|
|
- # cat /sys/kernel/debug/tracing/events/kmem/kmalloc/hist
|
|
- # trigger info: hist:keys=call_site.sym:vals=bytes_req:sort=bytes_req.descending:size=2048 [active]
|
|
-
|
|
- { call_site: [ffffffffa046041c] i915_gem_execbuffer2 [i915] } hitcount: 2186 bytes_req: 3397464
|
|
- { call_site: [ffffffffa045e7c4] i915_gem_do_execbuffer.isra.23 [i915] } hitcount: 1790 bytes_req: 712176
|
|
- { call_site: [ffffffff8125847d] ext4_htree_store_dirent } hitcount: 8132 bytes_req: 513135
|
|
- { call_site: [ffffffff811e2a1b] seq_buf_alloc } hitcount: 106 bytes_req: 440128
|
|
- { call_site: [ffffffffa0489a66] intel_ring_begin [i915] } hitcount: 2186 bytes_req: 314784
|
|
- { call_site: [ffffffff812891ca] ext4_find_extent } hitcount: 2174 bytes_req: 208992
|
|
- { call_site: [ffffffff811ae8e1] __kmalloc } hitcount: 8 bytes_req: 131072
|
|
- { call_site: [ffffffffa04c4a3c] intel_plane_duplicate_state [i915] } hitcount: 859 bytes_req: 116824
|
|
- { call_site: [ffffffffa02911f2] drm_modeset_lock_crtc [drm] } hitcount: 1834 bytes_req: 102704
|
|
- { call_site: [ffffffffa04a580c] intel_crtc_page_flip [i915] } hitcount: 972 bytes_req: 101088
|
|
- { call_site: [ffffffffa0287592] drm_mode_page_flip_ioctl [drm] } hitcount: 972 bytes_req: 85536
|
|
- { call_site: [ffffffffa00b7c06] hid_report_raw_event [hid] } hitcount: 3333 bytes_req: 66664
|
|
- { call_site: [ffffffff8137e559] sg_kmalloc } hitcount: 209 bytes_req: 61632
|
|
- .
|
|
- .
|
|
- .
|
|
- { call_site: [ffffffff81095225] alloc_fair_sched_group } hitcount: 2 bytes_req: 128
|
|
- { call_site: [ffffffff81097ec2] alloc_rt_sched_group } hitcount: 2 bytes_req: 128
|
|
- { call_site: [ffffffff812d8406] copy_semundo } hitcount: 2 bytes_req: 48
|
|
- { call_site: [ffffffff81200ba6] inotify_new_group } hitcount: 1 bytes_req: 48
|
|
- { call_site: [ffffffffa027121a] drm_getmagic [drm] } hitcount: 1 bytes_req: 48
|
|
- { call_site: [ffffffff811e3a25] __seq_open_private } hitcount: 1 bytes_req: 40
|
|
- { call_site: [ffffffff811c52f4] bprm_change_interp } hitcount: 2 bytes_req: 16
|
|
- { call_site: [ffffffff8154bc62] usb_control_msg } hitcount: 1 bytes_req: 8
|
|
- { call_site: [ffffffffa00bf1ca] hidraw_report_event [hid] } hitcount: 1 bytes_req: 7
|
|
- { call_site: [ffffffffa00bf6fe] hidraw_send_report [hid] } hitcount: 1 bytes_req: 7
|
|
-
|
|
- Totals:
|
|
- Hits: 32133
|
|
- Entries: 81
|
|
- Dropped: 0
|
|
-
|
|
- To display the offset and size information in addition to the symbol
|
|
- name, just use 'sym-offset' instead:
|
|
-
|
|
- # echo 'hist:key=call_site.sym-offset:val=bytes_req:sort=bytes_req.descending' > \
|
|
- /sys/kernel/debug/tracing/events/kmem/kmalloc/trigger
|
|
-
|
|
- # cat /sys/kernel/debug/tracing/events/kmem/kmalloc/hist
|
|
- # trigger info: hist:keys=call_site.sym-offset:vals=bytes_req:sort=bytes_req.descending:size=2048 [active]
|
|
-
|
|
- { call_site: [ffffffffa046041c] i915_gem_execbuffer2+0x6c/0x2c0 [i915] } hitcount: 4569 bytes_req: 3163720
|
|
- { call_site: [ffffffffa0489a66] intel_ring_begin+0xc6/0x1f0 [i915] } hitcount: 4569 bytes_req: 657936
|
|
- { call_site: [ffffffffa045e7c4] i915_gem_do_execbuffer.isra.23+0x694/0x1020 [i915] } hitcount: 1519 bytes_req: 472936
|
|
- { call_site: [ffffffffa045e646] i915_gem_do_execbuffer.isra.23+0x516/0x1020 [i915] } hitcount: 3050 bytes_req: 211832
|
|
- { call_site: [ffffffff811e2a1b] seq_buf_alloc+0x1b/0x50 } hitcount: 34 bytes_req: 148384
|
|
- { call_site: [ffffffffa04a580c] intel_crtc_page_flip+0xbc/0x870 [i915] } hitcount: 1385 bytes_req: 144040
|
|
- { call_site: [ffffffff811ae8e1] __kmalloc+0x191/0x1b0 } hitcount: 8 bytes_req: 131072
|
|
- { call_site: [ffffffffa0287592] drm_mode_page_flip_ioctl+0x282/0x360 [drm] } hitcount: 1385 bytes_req: 121880
|
|
- { call_site: [ffffffffa02911f2] drm_modeset_lock_crtc+0x32/0x100 [drm] } hitcount: 1848 bytes_req: 103488
|
|
- { call_site: [ffffffffa04c4a3c] intel_plane_duplicate_state+0x2c/0xa0 [i915] } hitcount: 461 bytes_req: 62696
|
|
- { call_site: [ffffffffa029070e] drm_vma_node_allow+0x2e/0xd0 [drm] } hitcount: 1541 bytes_req: 61640
|
|
- { call_site: [ffffffff815f8d7b] sk_prot_alloc+0xcb/0x1b0 } hitcount: 57 bytes_req: 57456
|
|
- .
|
|
- .
|
|
- .
|
|
- { call_site: [ffffffff8109524a] alloc_fair_sched_group+0x5a/0x1a0 } hitcount: 2 bytes_req: 128
|
|
- { call_site: [ffffffffa027b921] drm_vm_open_locked+0x31/0xa0 [drm] } hitcount: 3 bytes_req: 96
|
|
- { call_site: [ffffffff8122e266] proc_self_follow_link+0x76/0xb0 } hitcount: 8 bytes_req: 96
|
|
- { call_site: [ffffffff81213e80] load_elf_binary+0x240/0x1650 } hitcount: 3 bytes_req: 84
|
|
- { call_site: [ffffffff8154bc62] usb_control_msg+0x42/0x110 } hitcount: 1 bytes_req: 8
|
|
- { call_site: [ffffffffa00bf6fe] hidraw_send_report+0x7e/0x1a0 [hid] } hitcount: 1 bytes_req: 7
|
|
- { call_site: [ffffffffa00bf1ca] hidraw_report_event+0x8a/0x120 [hid] } hitcount: 1 bytes_req: 7
|
|
-
|
|
- Totals:
|
|
- Hits: 26098
|
|
- Entries: 64
|
|
- Dropped: 0
|
|
-
|
|
- We can also add multiple fields to the 'values' parameter. For
|
|
- example, we might want to see the total number of bytes allocated
|
|
- alongside bytes requested, and display the result sorted by bytes
|
|
- allocated in a descending order:
|
|
-
|
|
- # echo 'hist:keys=call_site.sym:values=bytes_req,bytes_alloc:sort=bytes_alloc.descending' > \
|
|
- /sys/kernel/debug/tracing/events/kmem/kmalloc/trigger
|
|
-
|
|
- # cat /sys/kernel/debug/tracing/events/kmem/kmalloc/hist
|
|
- # trigger info: hist:keys=call_site.sym:vals=bytes_req,bytes_alloc:sort=bytes_alloc.descending:size=2048 [active]
|
|
-
|
|
- { call_site: [ffffffffa046041c] i915_gem_execbuffer2 [i915] } hitcount: 7403 bytes_req: 4084360 bytes_alloc: 5958016
|
|
- { call_site: [ffffffff811e2a1b] seq_buf_alloc } hitcount: 541 bytes_req: 2213968 bytes_alloc: 2228224
|
|
- { call_site: [ffffffffa0489a66] intel_ring_begin [i915] } hitcount: 7404 bytes_req: 1066176 bytes_alloc: 1421568
|
|
- { call_site: [ffffffffa045e7c4] i915_gem_do_execbuffer.isra.23 [i915] } hitcount: 1565 bytes_req: 557368 bytes_alloc: 1037760
|
|
- { call_site: [ffffffff8125847d] ext4_htree_store_dirent } hitcount: 9557 bytes_req: 595778 bytes_alloc: 695744
|
|
- { call_site: [ffffffffa045e646] i915_gem_do_execbuffer.isra.23 [i915] } hitcount: 5839 bytes_req: 430680 bytes_alloc: 470400
|
|
- { call_site: [ffffffffa04c4a3c] intel_plane_duplicate_state [i915] } hitcount: 2388 bytes_req: 324768 bytes_alloc: 458496
|
|
- { call_site: [ffffffffa02911f2] drm_modeset_lock_crtc [drm] } hitcount: 3911 bytes_req: 219016 bytes_alloc: 250304
|
|
- { call_site: [ffffffff815f8d7b] sk_prot_alloc } hitcount: 235 bytes_req: 236880 bytes_alloc: 240640
|
|
- { call_site: [ffffffff8137e559] sg_kmalloc } hitcount: 557 bytes_req: 169024 bytes_alloc: 221760
|
|
- { call_site: [ffffffffa00b7c06] hid_report_raw_event [hid] } hitcount: 9378 bytes_req: 187548 bytes_alloc: 206312
|
|
- { call_site: [ffffffffa04a580c] intel_crtc_page_flip [i915] } hitcount: 1519 bytes_req: 157976 bytes_alloc: 194432
|
|
- .
|
|
- .
|
|
- .
|
|
- { call_site: [ffffffff8109bd3b] sched_autogroup_create_attach } hitcount: 2 bytes_req: 144 bytes_alloc: 192
|
|
- { call_site: [ffffffff81097ee8] alloc_rt_sched_group } hitcount: 2 bytes_req: 128 bytes_alloc: 128
|
|
- { call_site: [ffffffff8109524a] alloc_fair_sched_group } hitcount: 2 bytes_req: 128 bytes_alloc: 128
|
|
- { call_site: [ffffffff81095225] alloc_fair_sched_group } hitcount: 2 bytes_req: 128 bytes_alloc: 128
|
|
- { call_site: [ffffffff81097ec2] alloc_rt_sched_group } hitcount: 2 bytes_req: 128 bytes_alloc: 128
|
|
- { call_site: [ffffffff81213e80] load_elf_binary } hitcount: 3 bytes_req: 84 bytes_alloc: 96
|
|
- { call_site: [ffffffff81079a2e] kthread_create_on_node } hitcount: 1 bytes_req: 56 bytes_alloc: 64
|
|
- { call_site: [ffffffffa00bf6fe] hidraw_send_report [hid] } hitcount: 1 bytes_req: 7 bytes_alloc: 8
|
|
- { call_site: [ffffffff8154bc62] usb_control_msg } hitcount: 1 bytes_req: 8 bytes_alloc: 8
|
|
- { call_site: [ffffffffa00bf1ca] hidraw_report_event [hid] } hitcount: 1 bytes_req: 7 bytes_alloc: 8
|
|
-
|
|
- Totals:
|
|
- Hits: 66598
|
|
- Entries: 65
|
|
- Dropped: 0
|
|
-
|
|
- Finally, to finish off our kmalloc example, instead of simply having
|
|
- the hist trigger display symbolic call_sites, we can have the hist
|
|
- trigger additionally display the complete set of kernel stack traces
|
|
- that led to each call_site. To do that, we simply use the special
|
|
- value 'stacktrace' for the key parameter:
|
|
-
|
|
- # echo 'hist:keys=stacktrace:values=bytes_req,bytes_alloc:sort=bytes_alloc' > \
|
|
- /sys/kernel/debug/tracing/events/kmem/kmalloc/trigger
|
|
-
|
|
- The above trigger will use the kernel stack trace in effect when an
|
|
- event is triggered as the key for the hash table. This allows the
|
|
- enumeration of every kernel callpath that led up to a particular
|
|
- event, along with a running total of any of the event fields for
|
|
- that event. Here we tally bytes requested and bytes allocated for
|
|
- every callpath in the system that led up to a kmalloc (in this case
|
|
- every callpath to a kmalloc for a kernel compile):
|
|
-
|
|
- # cat /sys/kernel/debug/tracing/events/kmem/kmalloc/hist
|
|
- # trigger info: hist:keys=stacktrace:vals=bytes_req,bytes_alloc:sort=bytes_alloc:size=2048 [active]
|
|
-
|
|
- { stacktrace:
|
|
- __kmalloc_track_caller+0x10b/0x1a0
|
|
- kmemdup+0x20/0x50
|
|
- hidraw_report_event+0x8a/0x120 [hid]
|
|
- hid_report_raw_event+0x3ea/0x440 [hid]
|
|
- hid_input_report+0x112/0x190 [hid]
|
|
- hid_irq_in+0xc2/0x260 [usbhid]
|
|
- __usb_hcd_giveback_urb+0x72/0x120
|
|
- usb_giveback_urb_bh+0x9e/0xe0
|
|
- tasklet_hi_action+0xf8/0x100
|
|
- __do_softirq+0x114/0x2c0
|
|
- irq_exit+0xa5/0xb0
|
|
- do_IRQ+0x5a/0xf0
|
|
- ret_from_intr+0x0/0x30
|
|
- cpuidle_enter+0x17/0x20
|
|
- cpu_startup_entry+0x315/0x3e0
|
|
- rest_init+0x7c/0x80
|
|
- } hitcount: 3 bytes_req: 21 bytes_alloc: 24
|
|
- { stacktrace:
|
|
- __kmalloc_track_caller+0x10b/0x1a0
|
|
- kmemdup+0x20/0x50
|
|
- hidraw_report_event+0x8a/0x120 [hid]
|
|
- hid_report_raw_event+0x3ea/0x440 [hid]
|
|
- hid_input_report+0x112/0x190 [hid]
|
|
- hid_irq_in+0xc2/0x260 [usbhid]
|
|
- __usb_hcd_giveback_urb+0x72/0x120
|
|
- usb_giveback_urb_bh+0x9e/0xe0
|
|
- tasklet_hi_action+0xf8/0x100
|
|
- __do_softirq+0x114/0x2c0
|
|
- irq_exit+0xa5/0xb0
|
|
- do_IRQ+0x5a/0xf0
|
|
- ret_from_intr+0x0/0x30
|
|
- } hitcount: 3 bytes_req: 21 bytes_alloc: 24
|
|
- { stacktrace:
|
|
- kmem_cache_alloc_trace+0xeb/0x150
|
|
- aa_alloc_task_context+0x27/0x40
|
|
- apparmor_cred_prepare+0x1f/0x50
|
|
- security_prepare_creds+0x16/0x20
|
|
- prepare_creds+0xdf/0x1a0
|
|
- SyS_capset+0xb5/0x200
|
|
- system_call_fastpath+0x12/0x6a
|
|
- } hitcount: 1 bytes_req: 32 bytes_alloc: 32
|
|
- .
|
|
- .
|
|
- .
|
|
- { stacktrace:
|
|
- __kmalloc+0x11b/0x1b0
|
|
- i915_gem_execbuffer2+0x6c/0x2c0 [i915]
|
|
- drm_ioctl+0x349/0x670 [drm]
|
|
- do_vfs_ioctl+0x2f0/0x4f0
|
|
- SyS_ioctl+0x81/0xa0
|
|
- system_call_fastpath+0x12/0x6a
|
|
- } hitcount: 17726 bytes_req: 13944120 bytes_alloc: 19593808
|
|
- { stacktrace:
|
|
- __kmalloc+0x11b/0x1b0
|
|
- load_elf_phdrs+0x76/0xa0
|
|
- load_elf_binary+0x102/0x1650
|
|
- search_binary_handler+0x97/0x1d0
|
|
- do_execveat_common.isra.34+0x551/0x6e0
|
|
- SyS_execve+0x3a/0x50
|
|
- return_from_execve+0x0/0x23
|
|
- } hitcount: 33348 bytes_req: 17152128 bytes_alloc: 20226048
|
|
- { stacktrace:
|
|
- kmem_cache_alloc_trace+0xeb/0x150
|
|
- apparmor_file_alloc_security+0x27/0x40
|
|
- security_file_alloc+0x16/0x20
|
|
- get_empty_filp+0x93/0x1c0
|
|
- path_openat+0x31/0x5f0
|
|
- do_filp_open+0x3a/0x90
|
|
- do_sys_open+0x128/0x220
|
|
- SyS_open+0x1e/0x20
|
|
- system_call_fastpath+0x12/0x6a
|
|
- } hitcount: 4766422 bytes_req: 9532844 bytes_alloc: 38131376
|
|
- { stacktrace:
|
|
- __kmalloc+0x11b/0x1b0
|
|
- seq_buf_alloc+0x1b/0x50
|
|
- seq_read+0x2cc/0x370
|
|
- proc_reg_read+0x3d/0x80
|
|
- __vfs_read+0x28/0xe0
|
|
- vfs_read+0x86/0x140
|
|
- SyS_read+0x46/0xb0
|
|
- system_call_fastpath+0x12/0x6a
|
|
- } hitcount: 19133 bytes_req: 78368768 bytes_alloc: 78368768
|
|
-
|
|
- Totals:
|
|
- Hits: 6085872
|
|
- Entries: 253
|
|
- Dropped: 0
|
|
-
|
|
- If you key a hist trigger on common_pid, in order for example to
|
|
- gather and display sorted totals for each process, you can use the
|
|
- special .execname modifier to display the executable names for the
|
|
- processes in the table rather than raw pids. The example below
|
|
- keeps a per-process sum of total bytes read:
|
|
-
|
|
- # echo 'hist:key=common_pid.execname:val=count:sort=count.descending' > \
|
|
- /sys/kernel/debug/tracing/events/syscalls/sys_enter_read/trigger
|
|
-
|
|
- # cat /sys/kernel/debug/tracing/events/syscalls/sys_enter_read/hist
|
|
- # trigger info: hist:keys=common_pid.execname:vals=count:sort=count.descending:size=2048 [active]
|
|
-
|
|
- { common_pid: gnome-terminal [ 3196] } hitcount: 280 count: 1093512
|
|
- { common_pid: Xorg [ 1309] } hitcount: 525 count: 256640
|
|
- { common_pid: compiz [ 2889] } hitcount: 59 count: 254400
|
|
- { common_pid: bash [ 8710] } hitcount: 3 count: 66369
|
|
- { common_pid: dbus-daemon-lau [ 8703] } hitcount: 49 count: 47739
|
|
- { common_pid: irqbalance [ 1252] } hitcount: 27 count: 27648
|
|
- { common_pid: 01ifupdown [ 8705] } hitcount: 3 count: 17216
|
|
- { common_pid: dbus-daemon [ 772] } hitcount: 10 count: 12396
|
|
- { common_pid: Socket Thread [ 8342] } hitcount: 11 count: 11264
|
|
- { common_pid: nm-dhcp-client. [ 8701] } hitcount: 6 count: 7424
|
|
- { common_pid: gmain [ 1315] } hitcount: 18 count: 6336
|
|
- .
|
|
- .
|
|
- .
|
|
- { common_pid: postgres [ 1892] } hitcount: 2 count: 32
|
|
- { common_pid: postgres [ 1891] } hitcount: 2 count: 32
|
|
- { common_pid: gmain [ 8704] } hitcount: 2 count: 32
|
|
- { common_pid: upstart-dbus-br [ 2740] } hitcount: 21 count: 21
|
|
- { common_pid: nm-dispatcher.a [ 8696] } hitcount: 1 count: 16
|
|
- { common_pid: indicator-datet [ 2904] } hitcount: 1 count: 16
|
|
- { common_pid: gdbus [ 2998] } hitcount: 1 count: 16
|
|
- { common_pid: rtkit-daemon [ 2052] } hitcount: 1 count: 8
|
|
- { common_pid: init [ 1] } hitcount: 2 count: 2
|
|
-
|
|
- Totals:
|
|
- Hits: 2116
|
|
- Entries: 51
|
|
- Dropped: 0
|
|
-
|
|
- Similarly, if you key a hist trigger on syscall id, for example to
|
|
- gather and display a list of systemwide syscall hits, you can use
|
|
- the special .syscall modifier to display the syscall names rather
|
|
- than raw ids. The example below keeps a running total of syscall
|
|
- counts for the system during the run:
|
|
-
|
|
- # echo 'hist:key=id.syscall:val=hitcount' > \
|
|
- /sys/kernel/debug/tracing/events/raw_syscalls/sys_enter/trigger
|
|
-
|
|
- # cat /sys/kernel/debug/tracing/events/raw_syscalls/sys_enter/hist
|
|
- # trigger info: hist:keys=id.syscall:vals=hitcount:sort=hitcount:size=2048 [active]
|
|
-
|
|
- { id: sys_fsync [ 74] } hitcount: 1
|
|
- { id: sys_newuname [ 63] } hitcount: 1
|
|
- { id: sys_prctl [157] } hitcount: 1
|
|
- { id: sys_statfs [137] } hitcount: 1
|
|
- { id: sys_symlink [ 88] } hitcount: 1
|
|
- { id: sys_sendmmsg [307] } hitcount: 1
|
|
- { id: sys_semctl [ 66] } hitcount: 1
|
|
- { id: sys_readlink [ 89] } hitcount: 3
|
|
- { id: sys_bind [ 49] } hitcount: 3
|
|
- { id: sys_getsockname [ 51] } hitcount: 3
|
|
- { id: sys_unlink [ 87] } hitcount: 3
|
|
- { id: sys_rename [ 82] } hitcount: 4
|
|
- { id: unknown_syscall [ 58] } hitcount: 4
|
|
- { id: sys_connect [ 42] } hitcount: 4
|
|
- { id: sys_getpid [ 39] } hitcount: 4
|
|
- .
|
|
- .
|
|
- .
|
|
- { id: sys_rt_sigprocmask [ 14] } hitcount: 952
|
|
- { id: sys_futex [202] } hitcount: 1534
|
|
- { id: sys_write [ 1] } hitcount: 2689
|
|
- { id: sys_setitimer [ 38] } hitcount: 2797
|
|
- { id: sys_read [ 0] } hitcount: 3202
|
|
- { id: sys_select [ 23] } hitcount: 3773
|
|
- { id: sys_writev [ 20] } hitcount: 4531
|
|
- { id: sys_poll [ 7] } hitcount: 8314
|
|
- { id: sys_recvmsg [ 47] } hitcount: 13738
|
|
- { id: sys_ioctl [ 16] } hitcount: 21843
|
|
-
|
|
- Totals:
|
|
- Hits: 67612
|
|
- Entries: 72
|
|
- Dropped: 0
|
|
-
|
|
- The syscall counts above provide a rough overall picture of system
|
|
- call activity on the system; we can see for example that the most
|
|
- popular system call on this system was the 'sys_ioctl' system call.
|
|
-
|
|
- We can use 'compound' keys to refine that number and provide some
|
|
- further insight as to which processes exactly contribute to the
|
|
- overall ioctl count.
|
|
-
|
|
- The command below keeps a hitcount for every unique combination of
|
|
- system call id and pid - the end result is essentially a table
|
|
- that keeps a per-pid sum of system call hits. The results are
|
|
- sorted using the system call id as the primary key, and the
|
|
- hitcount sum as the secondary key:
|
|
-
|
|
- # echo 'hist:key=id.syscall,common_pid.execname:val=hitcount:sort=id,hitcount' > \
|
|
- /sys/kernel/debug/tracing/events/raw_syscalls/sys_enter/trigger
|
|
-
|
|
- # cat /sys/kernel/debug/tracing/events/raw_syscalls/sys_enter/hist
|
|
- # trigger info: hist:keys=id.syscall,common_pid.execname:vals=hitcount:sort=id.syscall,hitcount:size=2048 [active]
|
|
-
|
|
- { id: sys_read [ 0], common_pid: rtkit-daemon [ 1877] } hitcount: 1
|
|
- { id: sys_read [ 0], common_pid: gdbus [ 2976] } hitcount: 1
|
|
- { id: sys_read [ 0], common_pid: console-kit-dae [ 3400] } hitcount: 1
|
|
- { id: sys_read [ 0], common_pid: postgres [ 1865] } hitcount: 1
|
|
- { id: sys_read [ 0], common_pid: deja-dup-monito [ 3543] } hitcount: 2
|
|
- { id: sys_read [ 0], common_pid: NetworkManager [ 890] } hitcount: 2
|
|
- { id: sys_read [ 0], common_pid: evolution-calen [ 3048] } hitcount: 2
|
|
- { id: sys_read [ 0], common_pid: postgres [ 1864] } hitcount: 2
|
|
- { id: sys_read [ 0], common_pid: nm-applet [ 3022] } hitcount: 2
|
|
- { id: sys_read [ 0], common_pid: whoopsie [ 1212] } hitcount: 2
|
|
- .
|
|
- .
|
|
- .
|
|
- { id: sys_ioctl [ 16], common_pid: bash [ 8479] } hitcount: 1
|
|
- { id: sys_ioctl [ 16], common_pid: bash [ 3472] } hitcount: 12
|
|
- { id: sys_ioctl [ 16], common_pid: gnome-terminal [ 3199] } hitcount: 16
|
|
- { id: sys_ioctl [ 16], common_pid: Xorg [ 1267] } hitcount: 1808
|
|
- { id: sys_ioctl [ 16], common_pid: compiz [ 2994] } hitcount: 5580
|
|
- .
|
|
- .
|
|
- .
|
|
- { id: sys_waitid [247], common_pid: upstart-dbus-br [ 2690] } hitcount: 3
|
|
- { id: sys_waitid [247], common_pid: upstart-dbus-br [ 2688] } hitcount: 16
|
|
- { id: sys_inotify_add_watch [254], common_pid: gmain [ 975] } hitcount: 2
|
|
- { id: sys_inotify_add_watch [254], common_pid: gmain [ 3204] } hitcount: 4
|
|
- { id: sys_inotify_add_watch [254], common_pid: gmain [ 2888] } hitcount: 4
|
|
- { id: sys_inotify_add_watch [254], common_pid: gmain [ 3003] } hitcount: 4
|
|
- { id: sys_inotify_add_watch [254], common_pid: gmain [ 2873] } hitcount: 4
|
|
- { id: sys_inotify_add_watch [254], common_pid: gmain [ 3196] } hitcount: 6
|
|
- { id: sys_openat [257], common_pid: java [ 2623] } hitcount: 2
|
|
- { id: sys_eventfd2 [290], common_pid: ibus-ui-gtk3 [ 2760] } hitcount: 4
|
|
- { id: sys_eventfd2 [290], common_pid: compiz [ 2994] } hitcount: 6
|
|
-
|
|
- Totals:
|
|
- Hits: 31536
|
|
- Entries: 323
|
|
- Dropped: 0
|
|
-
|
|
- The above list does give us a breakdown of the ioctl syscall by
|
|
- pid, but it also gives us quite a bit more than that, which we
|
|
- don't really care about at the moment. Since we know the syscall
|
|
- id for sys_ioctl (16, displayed next to the sys_ioctl name), we
|
|
- can use that to filter out all the other syscalls:
|
|
-
|
|
- # echo 'hist:key=id.syscall,common_pid.execname:val=hitcount:sort=id,hitcount if id == 16' > \
|
|
- /sys/kernel/debug/tracing/events/raw_syscalls/sys_enter/trigger
|
|
-
|
|
- # cat /sys/kernel/debug/tracing/events/raw_syscalls/sys_enter/hist
|
|
- # trigger info: hist:keys=id.syscall,common_pid.execname:vals=hitcount:sort=id.syscall,hitcount:size=2048 if id == 16 [active]
|
|
-
|
|
- { id: sys_ioctl [ 16], common_pid: gmain [ 2769] } hitcount: 1
|
|
- { id: sys_ioctl [ 16], common_pid: evolution-addre [ 8571] } hitcount: 1
|
|
- { id: sys_ioctl [ 16], common_pid: gmain [ 3003] } hitcount: 1
|
|
- { id: sys_ioctl [ 16], common_pid: gmain [ 2781] } hitcount: 1
|
|
- { id: sys_ioctl [ 16], common_pid: gmain [ 2829] } hitcount: 1
|
|
- { id: sys_ioctl [ 16], common_pid: bash [ 8726] } hitcount: 1
|
|
- { id: sys_ioctl [ 16], common_pid: bash [ 8508] } hitcount: 1
|
|
- { id: sys_ioctl [ 16], common_pid: gmain [ 2970] } hitcount: 1
|
|
- { id: sys_ioctl [ 16], common_pid: gmain [ 2768] } hitcount: 1
|
|
- .
|
|
- .
|
|
- .
|
|
- { id: sys_ioctl [ 16], common_pid: pool [ 8559] } hitcount: 45
|
|
- { id: sys_ioctl [ 16], common_pid: pool [ 8555] } hitcount: 48
|
|
- { id: sys_ioctl [ 16], common_pid: pool [ 8551] } hitcount: 48
|
|
- { id: sys_ioctl [ 16], common_pid: avahi-daemon [ 896] } hitcount: 66
|
|
- { id: sys_ioctl [ 16], common_pid: Xorg [ 1267] } hitcount: 26674
|
|
- { id: sys_ioctl [ 16], common_pid: compiz [ 2994] } hitcount: 73443
|
|
-
|
|
- Totals:
|
|
- Hits: 101162
|
|
- Entries: 103
|
|
- Dropped: 0
|
|
-
|
|
- The above output shows that 'compiz' and 'Xorg' are far and away
|
|
- the heaviest ioctl callers (which might lead to questions about
|
|
- whether they really need to be making all those calls and to
|
|
- possible avenues for further investigation.)
|
|
-
|
|
- The compound key examples used a key and a sum value (hitcount) to
|
|
- sort the output, but we can just as easily use two keys instead.
|
|
- Here's an example where we use a compound key composed of the the
|
|
- common_pid and size event fields. Sorting with pid as the primary
|
|
- key and 'size' as the secondary key allows us to display an
|
|
- ordered summary of the recvfrom sizes, with counts, received by
|
|
- each process:
|
|
-
|
|
- # echo 'hist:key=common_pid.execname,size:val=hitcount:sort=common_pid,size' > \
|
|
- /sys/kernel/debug/tracing/events/syscalls/sys_enter_recvfrom/trigger
|
|
-
|
|
- # cat /sys/kernel/debug/tracing/events/syscalls/sys_enter_recvfrom/hist
|
|
- # trigger info: hist:keys=common_pid.execname,size:vals=hitcount:sort=common_pid.execname,size:size=2048 [active]
|
|
-
|
|
- { common_pid: smbd [ 784], size: 4 } hitcount: 1
|
|
- { common_pid: dnsmasq [ 1412], size: 4096 } hitcount: 672
|
|
- { common_pid: postgres [ 1796], size: 1000 } hitcount: 6
|
|
- { common_pid: postgres [ 1867], size: 1000 } hitcount: 10
|
|
- { common_pid: bamfdaemon [ 2787], size: 28 } hitcount: 2
|
|
- { common_pid: bamfdaemon [ 2787], size: 14360 } hitcount: 1
|
|
- { common_pid: compiz [ 2994], size: 8 } hitcount: 1
|
|
- { common_pid: compiz [ 2994], size: 20 } hitcount: 11
|
|
- { common_pid: gnome-terminal [ 3199], size: 4 } hitcount: 2
|
|
- { common_pid: firefox [ 8817], size: 4 } hitcount: 1
|
|
- { common_pid: firefox [ 8817], size: 8 } hitcount: 5
|
|
- { common_pid: firefox [ 8817], size: 588 } hitcount: 2
|
|
- { common_pid: firefox [ 8817], size: 628 } hitcount: 1
|
|
- { common_pid: firefox [ 8817], size: 6944 } hitcount: 1
|
|
- { common_pid: firefox [ 8817], size: 408880 } hitcount: 2
|
|
- { common_pid: firefox [ 8822], size: 8 } hitcount: 2
|
|
- { common_pid: firefox [ 8822], size: 160 } hitcount: 2
|
|
- { common_pid: firefox [ 8822], size: 320 } hitcount: 2
|
|
- { common_pid: firefox [ 8822], size: 352 } hitcount: 1
|
|
- .
|
|
- .
|
|
- .
|
|
- { common_pid: pool [ 8923], size: 1960 } hitcount: 10
|
|
- { common_pid: pool [ 8923], size: 2048 } hitcount: 10
|
|
- { common_pid: pool [ 8924], size: 1960 } hitcount: 10
|
|
- { common_pid: pool [ 8924], size: 2048 } hitcount: 10
|
|
- { common_pid: pool [ 8928], size: 1964 } hitcount: 4
|
|
- { common_pid: pool [ 8928], size: 1965 } hitcount: 2
|
|
- { common_pid: pool [ 8928], size: 2048 } hitcount: 6
|
|
- { common_pid: pool [ 8929], size: 1982 } hitcount: 1
|
|
- { common_pid: pool [ 8929], size: 2048 } hitcount: 1
|
|
-
|
|
- Totals:
|
|
- Hits: 2016
|
|
- Entries: 224
|
|
- Dropped: 0
|
|
-
|
|
- The above example also illustrates the fact that although a compound
|
|
- key is treated as a single entity for hashing purposes, the sub-keys
|
|
- it's composed of can be accessed independently.
|
|
-
|
|
- The next example uses a string field as the hash key and
|
|
- demonstrates how you can manually pause and continue a hist trigger.
|
|
- In this example, we'll aggregate fork counts and don't expect a
|
|
- large number of entries in the hash table, so we'll drop it to a
|
|
- much smaller number, say 256:
|
|
-
|
|
- # echo 'hist:key=child_comm:val=hitcount:size=256' > \
|
|
- /sys/kernel/debug/tracing/events/sched/sched_process_fork/trigger
|
|
-
|
|
- # cat /sys/kernel/debug/tracing/events/sched/sched_process_fork/hist
|
|
- # trigger info: hist:keys=child_comm:vals=hitcount:sort=hitcount:size=256 [active]
|
|
-
|
|
- { child_comm: dconf worker } hitcount: 1
|
|
- { child_comm: ibus-daemon } hitcount: 1
|
|
- { child_comm: whoopsie } hitcount: 1
|
|
- { child_comm: smbd } hitcount: 1
|
|
- { child_comm: gdbus } hitcount: 1
|
|
- { child_comm: kthreadd } hitcount: 1
|
|
- { child_comm: dconf worker } hitcount: 1
|
|
- { child_comm: evolution-alarm } hitcount: 2
|
|
- { child_comm: Socket Thread } hitcount: 2
|
|
- { child_comm: postgres } hitcount: 2
|
|
- { child_comm: bash } hitcount: 3
|
|
- { child_comm: compiz } hitcount: 3
|
|
- { child_comm: evolution-sourc } hitcount: 4
|
|
- { child_comm: dhclient } hitcount: 4
|
|
- { child_comm: pool } hitcount: 5
|
|
- { child_comm: nm-dispatcher.a } hitcount: 8
|
|
- { child_comm: firefox } hitcount: 8
|
|
- { child_comm: dbus-daemon } hitcount: 8
|
|
- { child_comm: glib-pacrunner } hitcount: 10
|
|
- { child_comm: evolution } hitcount: 23
|
|
-
|
|
- Totals:
|
|
- Hits: 89
|
|
- Entries: 20
|
|
- Dropped: 0
|
|
-
|
|
- If we want to pause the hist trigger, we can simply append :pause to
|
|
- the command that started the trigger. Notice that the trigger info
|
|
- displays as [paused]:
|
|
-
|
|
- # echo 'hist:key=child_comm:val=hitcount:size=256:pause' >> \
|
|
- /sys/kernel/debug/tracing/events/sched/sched_process_fork/trigger
|
|
-
|
|
- # cat /sys/kernel/debug/tracing/events/sched/sched_process_fork/hist
|
|
- # trigger info: hist:keys=child_comm:vals=hitcount:sort=hitcount:size=256 [paused]
|
|
-
|
|
- { child_comm: dconf worker } hitcount: 1
|
|
- { child_comm: kthreadd } hitcount: 1
|
|
- { child_comm: dconf worker } hitcount: 1
|
|
- { child_comm: gdbus } hitcount: 1
|
|
- { child_comm: ibus-daemon } hitcount: 1
|
|
- { child_comm: Socket Thread } hitcount: 2
|
|
- { child_comm: evolution-alarm } hitcount: 2
|
|
- { child_comm: smbd } hitcount: 2
|
|
- { child_comm: bash } hitcount: 3
|
|
- { child_comm: whoopsie } hitcount: 3
|
|
- { child_comm: compiz } hitcount: 3
|
|
- { child_comm: evolution-sourc } hitcount: 4
|
|
- { child_comm: pool } hitcount: 5
|
|
- { child_comm: postgres } hitcount: 6
|
|
- { child_comm: firefox } hitcount: 8
|
|
- { child_comm: dhclient } hitcount: 10
|
|
- { child_comm: emacs } hitcount: 12
|
|
- { child_comm: dbus-daemon } hitcount: 20
|
|
- { child_comm: nm-dispatcher.a } hitcount: 20
|
|
- { child_comm: evolution } hitcount: 35
|
|
- { child_comm: glib-pacrunner } hitcount: 59
|
|
-
|
|
- Totals:
|
|
- Hits: 199
|
|
- Entries: 21
|
|
- Dropped: 0
|
|
-
|
|
- To manually continue having the trigger aggregate events, append
|
|
- :cont instead. Notice that the trigger info displays as [active]
|
|
- again, and the data has changed:
|
|
-
|
|
- # echo 'hist:key=child_comm:val=hitcount:size=256:cont' >> \
|
|
- /sys/kernel/debug/tracing/events/sched/sched_process_fork/trigger
|
|
-
|
|
- # cat /sys/kernel/debug/tracing/events/sched/sched_process_fork/hist
|
|
- # trigger info: hist:keys=child_comm:vals=hitcount:sort=hitcount:size=256 [active]
|
|
-
|
|
- { child_comm: dconf worker } hitcount: 1
|
|
- { child_comm: dconf worker } hitcount: 1
|
|
- { child_comm: kthreadd } hitcount: 1
|
|
- { child_comm: gdbus } hitcount: 1
|
|
- { child_comm: ibus-daemon } hitcount: 1
|
|
- { child_comm: Socket Thread } hitcount: 2
|
|
- { child_comm: evolution-alarm } hitcount: 2
|
|
- { child_comm: smbd } hitcount: 2
|
|
- { child_comm: whoopsie } hitcount: 3
|
|
- { child_comm: compiz } hitcount: 3
|
|
- { child_comm: evolution-sourc } hitcount: 4
|
|
- { child_comm: bash } hitcount: 5
|
|
- { child_comm: pool } hitcount: 5
|
|
- { child_comm: postgres } hitcount: 6
|
|
- { child_comm: firefox } hitcount: 8
|
|
- { child_comm: dhclient } hitcount: 11
|
|
- { child_comm: emacs } hitcount: 12
|
|
- { child_comm: dbus-daemon } hitcount: 22
|
|
- { child_comm: nm-dispatcher.a } hitcount: 22
|
|
- { child_comm: evolution } hitcount: 35
|
|
- { child_comm: glib-pacrunner } hitcount: 59
|
|
-
|
|
- Totals:
|
|
- Hits: 206
|
|
- Entries: 21
|
|
- Dropped: 0
|
|
-
|
|
- The previous example showed how to start and stop a hist trigger by
|
|
- appending 'pause' and 'continue' to the hist trigger command. A
|
|
- hist trigger can also be started in a paused state by initially
|
|
- starting the trigger with ':pause' appended. This allows you to
|
|
- start the trigger only when you're ready to start collecting data
|
|
- and not before. For example, you could start the trigger in a
|
|
- paused state, then unpause it and do something you want to measure,
|
|
- then pause the trigger again when done.
|
|
-
|
|
- Of course, doing this manually can be difficult and error-prone, but
|
|
- it is possible to automatically start and stop a hist trigger based
|
|
- on some condition, via the enable_hist and disable_hist triggers.
|
|
-
|
|
- For example, suppose we wanted to take a look at the relative
|
|
- weights in terms of skb length for each callpath that leads to a
|
|
- netif_receieve_skb event when downloading a decent-sized file using
|
|
- wget.
|
|
-
|
|
- First we set up an initially paused stacktrace trigger on the
|
|
- netif_receive_skb event:
|
|
-
|
|
- # echo 'hist:key=stacktrace:vals=len:pause' > \
|
|
- /sys/kernel/debug/tracing/events/net/netif_receive_skb/trigger
|
|
-
|
|
- Next, we set up an 'enable_hist' trigger on the sched_process_exec
|
|
- event, with an 'if filename==/usr/bin/wget' filter. The effect of
|
|
- this new trigger is that it will 'unpause' the hist trigger we just
|
|
- set up on netif_receive_skb if and only if it sees a
|
|
- sched_process_exec event with a filename of '/usr/bin/wget'. When
|
|
- that happens, all netif_receive_skb events are aggregated into a
|
|
- hash table keyed on stacktrace:
|
|
-
|
|
- # echo 'enable_hist:net:netif_receive_skb if filename==/usr/bin/wget' > \
|
|
- /sys/kernel/debug/tracing/events/sched/sched_process_exec/trigger
|
|
-
|
|
- The aggregation continues until the netif_receive_skb is paused
|
|
- again, which is what the following disable_hist event does by
|
|
- creating a similar setup on the sched_process_exit event, using the
|
|
- filter 'comm==wget':
|
|
-
|
|
- # echo 'disable_hist:net:netif_receive_skb if comm==wget' > \
|
|
- /sys/kernel/debug/tracing/events/sched/sched_process_exit/trigger
|
|
-
|
|
- Whenever a process exits and the comm field of the disable_hist
|
|
- trigger filter matches 'comm==wget', the netif_receive_skb hist
|
|
- trigger is disabled.
|
|
-
|
|
- The overall effect is that netif_receive_skb events are aggregated
|
|
- into the hash table for only the duration of the wget. Executing a
|
|
- wget command and then listing the 'hist' file will display the
|
|
- output generated by the wget command:
|
|
-
|
|
- $ wget https://www.kernel.org/pub/linux/kernel/v3.x/patch-3.19.xz
|
|
-
|
|
- # cat /sys/kernel/debug/tracing/events/net/netif_receive_skb/hist
|
|
- # trigger info: hist:keys=stacktrace:vals=len:sort=hitcount:size=2048 [paused]
|
|
-
|
|
- { stacktrace:
|
|
- __netif_receive_skb_core+0x46d/0x990
|
|
- __netif_receive_skb+0x18/0x60
|
|
- netif_receive_skb_internal+0x23/0x90
|
|
- napi_gro_receive+0xc8/0x100
|
|
- ieee80211_deliver_skb+0xd6/0x270 [mac80211]
|
|
- ieee80211_rx_handlers+0xccf/0x22f0 [mac80211]
|
|
- ieee80211_prepare_and_rx_handle+0x4e7/0xc40 [mac80211]
|
|
- ieee80211_rx+0x31d/0x900 [mac80211]
|
|
- iwlagn_rx_reply_rx+0x3db/0x6f0 [iwldvm]
|
|
- iwl_rx_dispatch+0x8e/0xf0 [iwldvm]
|
|
- iwl_pcie_irq_handler+0xe3c/0x12f0 [iwlwifi]
|
|
- irq_thread_fn+0x20/0x50
|
|
- irq_thread+0x11f/0x150
|
|
- kthread+0xd2/0xf0
|
|
- ret_from_fork+0x42/0x70
|
|
- } hitcount: 85 len: 28884
|
|
- { stacktrace:
|
|
- __netif_receive_skb_core+0x46d/0x990
|
|
- __netif_receive_skb+0x18/0x60
|
|
- netif_receive_skb_internal+0x23/0x90
|
|
- napi_gro_complete+0xa4/0xe0
|
|
- dev_gro_receive+0x23a/0x360
|
|
- napi_gro_receive+0x30/0x100
|
|
- ieee80211_deliver_skb+0xd6/0x270 [mac80211]
|
|
- ieee80211_rx_handlers+0xccf/0x22f0 [mac80211]
|
|
- ieee80211_prepare_and_rx_handle+0x4e7/0xc40 [mac80211]
|
|
- ieee80211_rx+0x31d/0x900 [mac80211]
|
|
- iwlagn_rx_reply_rx+0x3db/0x6f0 [iwldvm]
|
|
- iwl_rx_dispatch+0x8e/0xf0 [iwldvm]
|
|
- iwl_pcie_irq_handler+0xe3c/0x12f0 [iwlwifi]
|
|
- irq_thread_fn+0x20/0x50
|
|
- irq_thread+0x11f/0x150
|
|
- kthread+0xd2/0xf0
|
|
- } hitcount: 98 len: 664329
|
|
- { stacktrace:
|
|
- __netif_receive_skb_core+0x46d/0x990
|
|
- __netif_receive_skb+0x18/0x60
|
|
- process_backlog+0xa8/0x150
|
|
- net_rx_action+0x15d/0x340
|
|
- __do_softirq+0x114/0x2c0
|
|
- do_softirq_own_stack+0x1c/0x30
|
|
- do_softirq+0x65/0x70
|
|
- __local_bh_enable_ip+0xb5/0xc0
|
|
- ip_finish_output+0x1f4/0x840
|
|
- ip_output+0x6b/0xc0
|
|
- ip_local_out_sk+0x31/0x40
|
|
- ip_send_skb+0x1a/0x50
|
|
- udp_send_skb+0x173/0x2a0
|
|
- udp_sendmsg+0x2bf/0x9f0
|
|
- inet_sendmsg+0x64/0xa0
|
|
- sock_sendmsg+0x3d/0x50
|
|
- } hitcount: 115 len: 13030
|
|
- { stacktrace:
|
|
- __netif_receive_skb_core+0x46d/0x990
|
|
- __netif_receive_skb+0x18/0x60
|
|
- netif_receive_skb_internal+0x23/0x90
|
|
- napi_gro_complete+0xa4/0xe0
|
|
- napi_gro_flush+0x6d/0x90
|
|
- iwl_pcie_irq_handler+0x92a/0x12f0 [iwlwifi]
|
|
- irq_thread_fn+0x20/0x50
|
|
- irq_thread+0x11f/0x150
|
|
- kthread+0xd2/0xf0
|
|
- ret_from_fork+0x42/0x70
|
|
- } hitcount: 934 len: 5512212
|
|
-
|
|
- Totals:
|
|
- Hits: 1232
|
|
- Entries: 4
|
|
- Dropped: 0
|
|
-
|
|
- The above shows all the netif_receive_skb callpaths and their total
|
|
- lengths for the duration of the wget command.
|
|
-
|
|
- The 'clear' hist trigger param can be used to clear the hash table.
|
|
- Suppose we wanted to try another run of the previous example but
|
|
- this time also wanted to see the complete list of events that went
|
|
- into the histogram. In order to avoid having to set everything up
|
|
- again, we can just clear the histogram first:
|
|
-
|
|
- # echo 'hist:key=stacktrace:vals=len:clear' >> \
|
|
- /sys/kernel/debug/tracing/events/net/netif_receive_skb/trigger
|
|
-
|
|
- Just to verify that it is in fact cleared, here's what we now see in
|
|
- the hist file:
|
|
-
|
|
- # cat /sys/kernel/debug/tracing/events/net/netif_receive_skb/hist
|
|
- # trigger info: hist:keys=stacktrace:vals=len:sort=hitcount:size=2048 [paused]
|
|
-
|
|
- Totals:
|
|
- Hits: 0
|
|
- Entries: 0
|
|
- Dropped: 0
|
|
-
|
|
- Since we want to see the detailed list of every netif_receive_skb
|
|
- event occurring during the new run, which are in fact the same
|
|
- events being aggregated into the hash table, we add some additional
|
|
- 'enable_event' events to the triggering sched_process_exec and
|
|
- sched_process_exit events as such:
|
|
-
|
|
- # echo 'enable_event:net:netif_receive_skb if filename==/usr/bin/wget' > \
|
|
- /sys/kernel/debug/tracing/events/sched/sched_process_exec/trigger
|
|
-
|
|
- # echo 'disable_event:net:netif_receive_skb if comm==wget' > \
|
|
- /sys/kernel/debug/tracing/events/sched/sched_process_exit/trigger
|
|
-
|
|
- If you read the trigger files for the sched_process_exec and
|
|
- sched_process_exit triggers, you should see two triggers for each:
|
|
- one enabling/disabling the hist aggregation and the other
|
|
- enabling/disabling the logging of events:
|
|
-
|
|
- # cat /sys/kernel/debug/tracing/events/sched/sched_process_exec/trigger
|
|
- enable_event:net:netif_receive_skb:unlimited if filename==/usr/bin/wget
|
|
- enable_hist:net:netif_receive_skb:unlimited if filename==/usr/bin/wget
|
|
-
|
|
- # cat /sys/kernel/debug/tracing/events/sched/sched_process_exit/trigger
|
|
- enable_event:net:netif_receive_skb:unlimited if comm==wget
|
|
- disable_hist:net:netif_receive_skb:unlimited if comm==wget
|
|
-
|
|
- In other words, whenever either of the sched_process_exec or
|
|
- sched_process_exit events is hit and matches 'wget', it enables or
|
|
- disables both the histogram and the event log, and what you end up
|
|
- with is a hash table and set of events just covering the specified
|
|
- duration. Run the wget command again:
|
|
-
|
|
- $ wget https://www.kernel.org/pub/linux/kernel/v3.x/patch-3.19.xz
|
|
-
|
|
- Displaying the 'hist' file should show something similar to what you
|
|
- saw in the last run, but this time you should also see the
|
|
- individual events in the trace file:
|
|
-
|
|
- # cat /sys/kernel/debug/tracing/trace
|
|
-
|
|
- # tracer: nop
|
|
- #
|
|
- # entries-in-buffer/entries-written: 183/1426 #P:4
|
|
- #
|
|
- # _-----=> irqs-off
|
|
- # / _----=> need-resched
|
|
- # | / _---=> hardirq/softirq
|
|
- # || / _--=> preempt-depth
|
|
- # ||| / delay
|
|
- # TASK-PID CPU# |||| TIMESTAMP FUNCTION
|
|
- # | | | |||| | |
|
|
- wget-15108 [000] ..s1 31769.606929: netif_receive_skb: dev=lo skbaddr=ffff88009c353100 len=60
|
|
- wget-15108 [000] ..s1 31769.606999: netif_receive_skb: dev=lo skbaddr=ffff88009c353200 len=60
|
|
- dnsmasq-1382 [000] ..s1 31769.677652: netif_receive_skb: dev=lo skbaddr=ffff88009c352b00 len=130
|
|
- dnsmasq-1382 [000] ..s1 31769.685917: netif_receive_skb: dev=lo skbaddr=ffff88009c352200 len=138
|
|
- ##### CPU 2 buffer started ####
|
|
- irq/29-iwlwifi-559 [002] ..s. 31772.031529: netif_receive_skb: dev=wlan0 skbaddr=ffff88009d433d00 len=2948
|
|
- irq/29-iwlwifi-559 [002] ..s. 31772.031572: netif_receive_skb: dev=wlan0 skbaddr=ffff88009d432200 len=1500
|
|
- irq/29-iwlwifi-559 [002] ..s. 31772.032196: netif_receive_skb: dev=wlan0 skbaddr=ffff88009d433100 len=2948
|
|
- irq/29-iwlwifi-559 [002] ..s. 31772.032761: netif_receive_skb: dev=wlan0 skbaddr=ffff88009d433000 len=2948
|
|
- irq/29-iwlwifi-559 [002] ..s. 31772.033220: netif_receive_skb: dev=wlan0 skbaddr=ffff88009d432e00 len=1500
|
|
- .
|
|
- .
|
|
- .
|
|
-
|
|
- The following example demonstrates how multiple hist triggers can be
|
|
- attached to a given event. This capability can be useful for
|
|
- creating a set of different summaries derived from the same set of
|
|
- events, or for comparing the effects of different filters, among
|
|
- other things.
|
|
-
|
|
- # echo 'hist:keys=skbaddr.hex:vals=len if len < 0' >> \
|
|
- /sys/kernel/debug/tracing/events/net/netif_receive_skb/trigger
|
|
- # echo 'hist:keys=skbaddr.hex:vals=len if len > 4096' >> \
|
|
- /sys/kernel/debug/tracing/events/net/netif_receive_skb/trigger
|
|
- # echo 'hist:keys=skbaddr.hex:vals=len if len == 256' >> \
|
|
- /sys/kernel/debug/tracing/events/net/netif_receive_skb/trigger
|
|
- # echo 'hist:keys=skbaddr.hex:vals=len' >> \
|
|
- /sys/kernel/debug/tracing/events/net/netif_receive_skb/trigger
|
|
- # echo 'hist:keys=len:vals=common_preempt_count' >> \
|
|
- /sys/kernel/debug/tracing/events/net/netif_receive_skb/trigger
|
|
-
|
|
- The above set of commands create four triggers differing only in
|
|
- their filters, along with a completely different though fairly
|
|
- nonsensical trigger. Note that in order to append multiple hist
|
|
- triggers to the same file, you should use the '>>' operator to
|
|
- append them ('>' will also add the new hist trigger, but will remove
|
|
- any existing hist triggers beforehand).
|
|
-
|
|
- Displaying the contents of the 'hist' file for the event shows the
|
|
- contents of all five histograms:
|
|
-
|
|
- # cat /sys/kernel/debug/tracing/events/net/netif_receive_skb/hist
|
|
-
|
|
- # event histogram
|
|
- #
|
|
- # trigger info: hist:keys=len:vals=hitcount,common_preempt_count:sort=hitcount:size=2048 [active]
|
|
- #
|
|
-
|
|
- { len: 176 } hitcount: 1 common_preempt_count: 0
|
|
- { len: 223 } hitcount: 1 common_preempt_count: 0
|
|
- { len: 4854 } hitcount: 1 common_preempt_count: 0
|
|
- { len: 395 } hitcount: 1 common_preempt_count: 0
|
|
- { len: 177 } hitcount: 1 common_preempt_count: 0
|
|
- { len: 446 } hitcount: 1 common_preempt_count: 0
|
|
- { len: 1601 } hitcount: 1 common_preempt_count: 0
|
|
- .
|
|
- .
|
|
- .
|
|
- { len: 1280 } hitcount: 66 common_preempt_count: 0
|
|
- { len: 116 } hitcount: 81 common_preempt_count: 40
|
|
- { len: 708 } hitcount: 112 common_preempt_count: 0
|
|
- { len: 46 } hitcount: 221 common_preempt_count: 0
|
|
- { len: 1264 } hitcount: 458 common_preempt_count: 0
|
|
-
|
|
- Totals:
|
|
- Hits: 1428
|
|
- Entries: 147
|
|
- Dropped: 0
|
|
-
|
|
-
|
|
- # event histogram
|
|
- #
|
|
- # trigger info: hist:keys=skbaddr.hex:vals=hitcount,len:sort=hitcount:size=2048 [active]
|
|
- #
|
|
-
|
|
- { skbaddr: ffff8800baee5e00 } hitcount: 1 len: 130
|
|
- { skbaddr: ffff88005f3d5600 } hitcount: 1 len: 1280
|
|
- { skbaddr: ffff88005f3d4900 } hitcount: 1 len: 1280
|
|
- { skbaddr: ffff88009fed6300 } hitcount: 1 len: 115
|
|
- { skbaddr: ffff88009fe0ad00 } hitcount: 1 len: 115
|
|
- { skbaddr: ffff88008cdb1900 } hitcount: 1 len: 46
|
|
- { skbaddr: ffff880064b5ef00 } hitcount: 1 len: 118
|
|
- { skbaddr: ffff880044e3c700 } hitcount: 1 len: 60
|
|
- { skbaddr: ffff880100065900 } hitcount: 1 len: 46
|
|
- { skbaddr: ffff8800d46bd500 } hitcount: 1 len: 116
|
|
- { skbaddr: ffff88005f3d5f00 } hitcount: 1 len: 1280
|
|
- { skbaddr: ffff880100064700 } hitcount: 1 len: 365
|
|
- { skbaddr: ffff8800badb6f00 } hitcount: 1 len: 60
|
|
- .
|
|
- .
|
|
- .
|
|
- { skbaddr: ffff88009fe0be00 } hitcount: 27 len: 24677
|
|
- { skbaddr: ffff88009fe0a400 } hitcount: 27 len: 23052
|
|
- { skbaddr: ffff88009fe0b700 } hitcount: 31 len: 25589
|
|
- { skbaddr: ffff88009fe0b600 } hitcount: 32 len: 27326
|
|
- { skbaddr: ffff88006a462800 } hitcount: 68 len: 71678
|
|
- { skbaddr: ffff88006a463700 } hitcount: 70 len: 72678
|
|
- { skbaddr: ffff88006a462b00 } hitcount: 71 len: 77589
|
|
- { skbaddr: ffff88006a463600 } hitcount: 73 len: 71307
|
|
- { skbaddr: ffff88006a462200 } hitcount: 81 len: 81032
|
|
-
|
|
- Totals:
|
|
- Hits: 1451
|
|
- Entries: 318
|
|
- Dropped: 0
|
|
-
|
|
-
|
|
- # event histogram
|
|
- #
|
|
- # trigger info: hist:keys=skbaddr.hex:vals=hitcount,len:sort=hitcount:size=2048 if len == 256 [active]
|
|
- #
|
|
-
|
|
-
|
|
- Totals:
|
|
- Hits: 0
|
|
- Entries: 0
|
|
- Dropped: 0
|
|
-
|
|
-
|
|
- # event histogram
|
|
- #
|
|
- # trigger info: hist:keys=skbaddr.hex:vals=hitcount,len:sort=hitcount:size=2048 if len > 4096 [active]
|
|
- #
|
|
-
|
|
- { skbaddr: ffff88009fd2c300 } hitcount: 1 len: 7212
|
|
- { skbaddr: ffff8800d2bcce00 } hitcount: 1 len: 7212
|
|
- { skbaddr: ffff8800d2bcd700 } hitcount: 1 len: 7212
|
|
- { skbaddr: ffff8800d2bcda00 } hitcount: 1 len: 21492
|
|
- { skbaddr: ffff8800ae2e2d00 } hitcount: 1 len: 7212
|
|
- { skbaddr: ffff8800d2bcdb00 } hitcount: 1 len: 7212
|
|
- { skbaddr: ffff88006a4df500 } hitcount: 1 len: 4854
|
|
- { skbaddr: ffff88008ce47b00 } hitcount: 1 len: 18636
|
|
- { skbaddr: ffff8800ae2e2200 } hitcount: 1 len: 12924
|
|
- { skbaddr: ffff88005f3e1000 } hitcount: 1 len: 4356
|
|
- { skbaddr: ffff8800d2bcdc00 } hitcount: 2 len: 24420
|
|
- { skbaddr: ffff8800d2bcc200 } hitcount: 2 len: 12996
|
|
-
|
|
- Totals:
|
|
- Hits: 14
|
|
- Entries: 12
|
|
- Dropped: 0
|
|
-
|
|
-
|
|
- # event histogram
|
|
- #
|
|
- # trigger info: hist:keys=skbaddr.hex:vals=hitcount,len:sort=hitcount:size=2048 if len < 0 [active]
|
|
- #
|
|
-
|
|
-
|
|
- Totals:
|
|
- Hits: 0
|
|
- Entries: 0
|
|
- Dropped: 0
|
|
-
|
|
- Named triggers can be used to have triggers share a common set of
|
|
- histogram data. This capability is mostly useful for combining the
|
|
- output of events generated by tracepoints contained inside inline
|
|
- functions, but names can be used in a hist trigger on any event.
|
|
- For example, these two triggers when hit will update the same 'len'
|
|
- field in the shared 'foo' histogram data:
|
|
-
|
|
- # echo 'hist:name=foo:keys=skbaddr.hex:vals=len' > \
|
|
- /sys/kernel/debug/tracing/events/net/netif_receive_skb/trigger
|
|
- # echo 'hist:name=foo:keys=skbaddr.hex:vals=len' > \
|
|
- /sys/kernel/debug/tracing/events/net/netif_rx/trigger
|
|
-
|
|
- You can see that they're updating common histogram data by reading
|
|
- each event's hist files at the same time:
|
|
-
|
|
- # cat /sys/kernel/debug/tracing/events/net/netif_receive_skb/hist;
|
|
- cat /sys/kernel/debug/tracing/events/net/netif_rx/hist
|
|
-
|
|
- # event histogram
|
|
- #
|
|
- # trigger info: hist:name=foo:keys=skbaddr.hex:vals=hitcount,len:sort=hitcount:size=2048 [active]
|
|
- #
|
|
-
|
|
- { skbaddr: ffff88000ad53500 } hitcount: 1 len: 46
|
|
- { skbaddr: ffff8800af5a1500 } hitcount: 1 len: 76
|
|
- { skbaddr: ffff8800d62a1900 } hitcount: 1 len: 46
|
|
- { skbaddr: ffff8800d2bccb00 } hitcount: 1 len: 468
|
|
- { skbaddr: ffff8800d3c69900 } hitcount: 1 len: 46
|
|
- { skbaddr: ffff88009ff09100 } hitcount: 1 len: 52
|
|
- { skbaddr: ffff88010f13ab00 } hitcount: 1 len: 168
|
|
- { skbaddr: ffff88006a54f400 } hitcount: 1 len: 46
|
|
- { skbaddr: ffff8800d2bcc500 } hitcount: 1 len: 260
|
|
- { skbaddr: ffff880064505000 } hitcount: 1 len: 46
|
|
- { skbaddr: ffff8800baf24e00 } hitcount: 1 len: 32
|
|
- { skbaddr: ffff88009fe0ad00 } hitcount: 1 len: 46
|
|
- { skbaddr: ffff8800d3edff00 } hitcount: 1 len: 44
|
|
- { skbaddr: ffff88009fe0b400 } hitcount: 1 len: 168
|
|
- { skbaddr: ffff8800a1c55a00 } hitcount: 1 len: 40
|
|
- { skbaddr: ffff8800d2bcd100 } hitcount: 1 len: 40
|
|
- { skbaddr: ffff880064505f00 } hitcount: 1 len: 174
|
|
- { skbaddr: ffff8800a8bff200 } hitcount: 1 len: 160
|
|
- { skbaddr: ffff880044e3cc00 } hitcount: 1 len: 76
|
|
- { skbaddr: ffff8800a8bfe700 } hitcount: 1 len: 46
|
|
- { skbaddr: ffff8800d2bcdc00 } hitcount: 1 len: 32
|
|
- { skbaddr: ffff8800a1f64800 } hitcount: 1 len: 46
|
|
- { skbaddr: ffff8800d2bcde00 } hitcount: 1 len: 988
|
|
- { skbaddr: ffff88006a5dea00 } hitcount: 1 len: 46
|
|
- { skbaddr: ffff88002e37a200 } hitcount: 1 len: 44
|
|
- { skbaddr: ffff8800a1f32c00 } hitcount: 2 len: 676
|
|
- { skbaddr: ffff88000ad52600 } hitcount: 2 len: 107
|
|
- { skbaddr: ffff8800a1f91e00 } hitcount: 2 len: 92
|
|
- { skbaddr: ffff8800af5a0200 } hitcount: 2 len: 142
|
|
- { skbaddr: ffff8800d2bcc600 } hitcount: 2 len: 220
|
|
- { skbaddr: ffff8800ba36f500 } hitcount: 2 len: 92
|
|
- { skbaddr: ffff8800d021f800 } hitcount: 2 len: 92
|
|
- { skbaddr: ffff8800a1f33600 } hitcount: 2 len: 675
|
|
- { skbaddr: ffff8800a8bfff00 } hitcount: 3 len: 138
|
|
- { skbaddr: ffff8800d62a1300 } hitcount: 3 len: 138
|
|
- { skbaddr: ffff88002e37a100 } hitcount: 4 len: 184
|
|
- { skbaddr: ffff880064504400 } hitcount: 4 len: 184
|
|
- { skbaddr: ffff8800a8bfec00 } hitcount: 4 len: 184
|
|
- { skbaddr: ffff88000ad53700 } hitcount: 5 len: 230
|
|
- { skbaddr: ffff8800d2bcdb00 } hitcount: 5 len: 196
|
|
- { skbaddr: ffff8800a1f90000 } hitcount: 6 len: 276
|
|
- { skbaddr: ffff88006a54f900 } hitcount: 6 len: 276
|
|
-
|
|
- Totals:
|
|
- Hits: 81
|
|
- Entries: 42
|
|
- Dropped: 0
|
|
- # event histogram
|
|
- #
|
|
- # trigger info: hist:name=foo:keys=skbaddr.hex:vals=hitcount,len:sort=hitcount:size=2048 [active]
|
|
- #
|
|
-
|
|
- { skbaddr: ffff88000ad53500 } hitcount: 1 len: 46
|
|
- { skbaddr: ffff8800af5a1500 } hitcount: 1 len: 76
|
|
- { skbaddr: ffff8800d62a1900 } hitcount: 1 len: 46
|
|
- { skbaddr: ffff8800d2bccb00 } hitcount: 1 len: 468
|
|
- { skbaddr: ffff8800d3c69900 } hitcount: 1 len: 46
|
|
- { skbaddr: ffff88009ff09100 } hitcount: 1 len: 52
|
|
- { skbaddr: ffff88010f13ab00 } hitcount: 1 len: 168
|
|
- { skbaddr: ffff88006a54f400 } hitcount: 1 len: 46
|
|
- { skbaddr: ffff8800d2bcc500 } hitcount: 1 len: 260
|
|
- { skbaddr: ffff880064505000 } hitcount: 1 len: 46
|
|
- { skbaddr: ffff8800baf24e00 } hitcount: 1 len: 32
|
|
- { skbaddr: ffff88009fe0ad00 } hitcount: 1 len: 46
|
|
- { skbaddr: ffff8800d3edff00 } hitcount: 1 len: 44
|
|
- { skbaddr: ffff88009fe0b400 } hitcount: 1 len: 168
|
|
- { skbaddr: ffff8800a1c55a00 } hitcount: 1 len: 40
|
|
- { skbaddr: ffff8800d2bcd100 } hitcount: 1 len: 40
|
|
- { skbaddr: ffff880064505f00 } hitcount: 1 len: 174
|
|
- { skbaddr: ffff8800a8bff200 } hitcount: 1 len: 160
|
|
- { skbaddr: ffff880044e3cc00 } hitcount: 1 len: 76
|
|
- { skbaddr: ffff8800a8bfe700 } hitcount: 1 len: 46
|
|
- { skbaddr: ffff8800d2bcdc00 } hitcount: 1 len: 32
|
|
- { skbaddr: ffff8800a1f64800 } hitcount: 1 len: 46
|
|
- { skbaddr: ffff8800d2bcde00 } hitcount: 1 len: 988
|
|
- { skbaddr: ffff88006a5dea00 } hitcount: 1 len: 46
|
|
- { skbaddr: ffff88002e37a200 } hitcount: 1 len: 44
|
|
- { skbaddr: ffff8800a1f32c00 } hitcount: 2 len: 676
|
|
- { skbaddr: ffff88000ad52600 } hitcount: 2 len: 107
|
|
- { skbaddr: ffff8800a1f91e00 } hitcount: 2 len: 92
|
|
- { skbaddr: ffff8800af5a0200 } hitcount: 2 len: 142
|
|
- { skbaddr: ffff8800d2bcc600 } hitcount: 2 len: 220
|
|
- { skbaddr: ffff8800ba36f500 } hitcount: 2 len: 92
|
|
- { skbaddr: ffff8800d021f800 } hitcount: 2 len: 92
|
|
- { skbaddr: ffff8800a1f33600 } hitcount: 2 len: 675
|
|
- { skbaddr: ffff8800a8bfff00 } hitcount: 3 len: 138
|
|
- { skbaddr: ffff8800d62a1300 } hitcount: 3 len: 138
|
|
- { skbaddr: ffff88002e37a100 } hitcount: 4 len: 184
|
|
- { skbaddr: ffff880064504400 } hitcount: 4 len: 184
|
|
- { skbaddr: ffff8800a8bfec00 } hitcount: 4 len: 184
|
|
- { skbaddr: ffff88000ad53700 } hitcount: 5 len: 230
|
|
- { skbaddr: ffff8800d2bcdb00 } hitcount: 5 len: 196
|
|
- { skbaddr: ffff8800a1f90000 } hitcount: 6 len: 276
|
|
- { skbaddr: ffff88006a54f900 } hitcount: 6 len: 276
|
|
-
|
|
- Totals:
|
|
- Hits: 81
|
|
- Entries: 42
|
|
- Dropped: 0
|
|
-
|
|
- And here's an example that shows how to combine histogram data from
|
|
- any two events even if they don't share any 'compatible' fields
|
|
- other than 'hitcount' and 'stacktrace'. These commands create a
|
|
- couple of triggers named 'bar' using those fields:
|
|
-
|
|
- # echo 'hist:name=bar:key=stacktrace:val=hitcount' > \
|
|
- /sys/kernel/debug/tracing/events/sched/sched_process_fork/trigger
|
|
- # echo 'hist:name=bar:key=stacktrace:val=hitcount' > \
|
|
- /sys/kernel/debug/tracing/events/net/netif_rx/trigger
|
|
-
|
|
- And displaying the output of either shows some interesting if
|
|
- somewhat confusing output:
|
|
-
|
|
- # cat /sys/kernel/debug/tracing/events/sched/sched_process_fork/hist
|
|
- # cat /sys/kernel/debug/tracing/events/net/netif_rx/hist
|
|
-
|
|
- # event histogram
|
|
- #
|
|
- # trigger info: hist:name=bar:keys=stacktrace:vals=hitcount:sort=hitcount:size=2048 [active]
|
|
- #
|
|
-
|
|
- { stacktrace:
|
|
- _do_fork+0x18e/0x330
|
|
- kernel_thread+0x29/0x30
|
|
- kthreadd+0x154/0x1b0
|
|
- ret_from_fork+0x3f/0x70
|
|
- } hitcount: 1
|
|
- { stacktrace:
|
|
- netif_rx_internal+0xb2/0xd0
|
|
- netif_rx_ni+0x20/0x70
|
|
- dev_loopback_xmit+0xaa/0xd0
|
|
- ip_mc_output+0x126/0x240
|
|
- ip_local_out_sk+0x31/0x40
|
|
- igmp_send_report+0x1e9/0x230
|
|
- igmp_timer_expire+0xe9/0x120
|
|
- call_timer_fn+0x39/0xf0
|
|
- run_timer_softirq+0x1e1/0x290
|
|
- __do_softirq+0xfd/0x290
|
|
- irq_exit+0x98/0xb0
|
|
- smp_apic_timer_interrupt+0x4a/0x60
|
|
- apic_timer_interrupt+0x6d/0x80
|
|
- cpuidle_enter+0x17/0x20
|
|
- call_cpuidle+0x3b/0x60
|
|
- cpu_startup_entry+0x22d/0x310
|
|
- } hitcount: 1
|
|
- { stacktrace:
|
|
- netif_rx_internal+0xb2/0xd0
|
|
- netif_rx_ni+0x20/0x70
|
|
- dev_loopback_xmit+0xaa/0xd0
|
|
- ip_mc_output+0x17f/0x240
|
|
- ip_local_out_sk+0x31/0x40
|
|
- ip_send_skb+0x1a/0x50
|
|
- udp_send_skb+0x13e/0x270
|
|
- udp_sendmsg+0x2bf/0x980
|
|
- inet_sendmsg+0x67/0xa0
|
|
- sock_sendmsg+0x38/0x50
|
|
- SYSC_sendto+0xef/0x170
|
|
- SyS_sendto+0xe/0x10
|
|
- entry_SYSCALL_64_fastpath+0x12/0x6a
|
|
- } hitcount: 2
|
|
- { stacktrace:
|
|
- netif_rx_internal+0xb2/0xd0
|
|
- netif_rx+0x1c/0x60
|
|
- loopback_xmit+0x6c/0xb0
|
|
- dev_hard_start_xmit+0x219/0x3a0
|
|
- __dev_queue_xmit+0x415/0x4f0
|
|
- dev_queue_xmit_sk+0x13/0x20
|
|
- ip_finish_output2+0x237/0x340
|
|
- ip_finish_output+0x113/0x1d0
|
|
- ip_output+0x66/0xc0
|
|
- ip_local_out_sk+0x31/0x40
|
|
- ip_send_skb+0x1a/0x50
|
|
- udp_send_skb+0x16d/0x270
|
|
- udp_sendmsg+0x2bf/0x980
|
|
- inet_sendmsg+0x67/0xa0
|
|
- sock_sendmsg+0x38/0x50
|
|
- ___sys_sendmsg+0x14e/0x270
|
|
- } hitcount: 76
|
|
- { stacktrace:
|
|
- netif_rx_internal+0xb2/0xd0
|
|
- netif_rx+0x1c/0x60
|
|
- loopback_xmit+0x6c/0xb0
|
|
- dev_hard_start_xmit+0x219/0x3a0
|
|
- __dev_queue_xmit+0x415/0x4f0
|
|
- dev_queue_xmit_sk+0x13/0x20
|
|
- ip_finish_output2+0x237/0x340
|
|
- ip_finish_output+0x113/0x1d0
|
|
- ip_output+0x66/0xc0
|
|
- ip_local_out_sk+0x31/0x40
|
|
- ip_send_skb+0x1a/0x50
|
|
- udp_send_skb+0x16d/0x270
|
|
- udp_sendmsg+0x2bf/0x980
|
|
- inet_sendmsg+0x67/0xa0
|
|
- sock_sendmsg+0x38/0x50
|
|
- ___sys_sendmsg+0x269/0x270
|
|
- } hitcount: 77
|
|
- { stacktrace:
|
|
- netif_rx_internal+0xb2/0xd0
|
|
- netif_rx+0x1c/0x60
|
|
- loopback_xmit+0x6c/0xb0
|
|
- dev_hard_start_xmit+0x219/0x3a0
|
|
- __dev_queue_xmit+0x415/0x4f0
|
|
- dev_queue_xmit_sk+0x13/0x20
|
|
- ip_finish_output2+0x237/0x340
|
|
- ip_finish_output+0x113/0x1d0
|
|
- ip_output+0x66/0xc0
|
|
- ip_local_out_sk+0x31/0x40
|
|
- ip_send_skb+0x1a/0x50
|
|
- udp_send_skb+0x16d/0x270
|
|
- udp_sendmsg+0x2bf/0x980
|
|
- inet_sendmsg+0x67/0xa0
|
|
- sock_sendmsg+0x38/0x50
|
|
- SYSC_sendto+0xef/0x170
|
|
- } hitcount: 88
|
|
- { stacktrace:
|
|
- _do_fork+0x18e/0x330
|
|
- SyS_clone+0x19/0x20
|
|
- entry_SYSCALL_64_fastpath+0x12/0x6a
|
|
- } hitcount: 244
|
|
-
|
|
- Totals:
|
|
- Hits: 489
|
|
- Entries: 7
|
|
- Dropped: 0
|
|
+ See Documentation/trace/histogram.txt for details and examples.
|
|
--- /dev/null
|
|
+++ b/Documentation/trace/histogram.txt
|
|
@@ -0,0 +1,1568 @@
|
|
+ Event Histograms
|
|
+
|
|
+ Documentation written by Tom Zanussi
|
|
+
|
|
+1. Introduction
|
|
+===============
|
|
+
|
|
+ Histogram triggers are special event triggers that can be used to
|
|
+ aggregate trace event data into histograms. For information on
|
|
+ trace events and event triggers, see Documentation/trace/events.txt.
|
|
+
|
|
+
|
|
+2. Histogram Trigger Command
|
|
+============================
|
|
+
|
|
+ A histogram trigger command is an event trigger command that
|
|
+ aggregates event hits into a hash table keyed on one or more trace
|
|
+ event format fields (or stacktrace) and a set of running totals
|
|
+ derived from one or more trace event format fields and/or event
|
|
+ counts (hitcount).
|
|
+
|
|
+ The format of a hist trigger is as follows:
|
|
+
|
|
+ hist:keys=<field1[,field2,...]>[:values=<field1[,field2,...]>]
|
|
+ [:sort=<field1[,field2,...]>][:size=#entries][:pause][:continue]
|
|
+ [:clear][:name=histname1] [if <filter>]
|
|
+
|
|
+ When a matching event is hit, an entry is added to a hash table
|
|
+ using the key(s) and value(s) named. Keys and values correspond to
|
|
+ fields in the event's format description. Values must correspond to
|
|
+ numeric fields - on an event hit, the value(s) will be added to a
|
|
+ sum kept for that field. The special string 'hitcount' can be used
|
|
+ in place of an explicit value field - this is simply a count of
|
|
+ event hits. If 'values' isn't specified, an implicit 'hitcount'
|
|
+ value will be automatically created and used as the only value.
|
|
+ Keys can be any field, or the special string 'stacktrace', which
|
|
+ will use the event's kernel stacktrace as the key. The keywords
|
|
+ 'keys' or 'key' can be used to specify keys, and the keywords
|
|
+ 'values', 'vals', or 'val' can be used to specify values. Compound
|
|
+ keys consisting of up to two fields can be specified by the 'keys'
|
|
+ keyword. Hashing a compound key produces a unique entry in the
|
|
+ table for each unique combination of component keys, and can be
|
|
+ useful for providing more fine-grained summaries of event data.
|
|
+ Additionally, sort keys consisting of up to two fields can be
|
|
+ specified by the 'sort' keyword. If more than one field is
|
|
+ specified, the result will be a 'sort within a sort': the first key
|
|
+ is taken to be the primary sort key and the second the secondary
|
|
+ key. If a hist trigger is given a name using the 'name' parameter,
|
|
+ its histogram data will be shared with other triggers of the same
|
|
+ name, and trigger hits will update this common data. Only triggers
|
|
+ with 'compatible' fields can be combined in this way; triggers are
|
|
+ 'compatible' if the fields named in the trigger share the same
|
|
+ number and type of fields and those fields also have the same names.
|
|
+ Note that any two events always share the compatible 'hitcount' and
|
|
+ 'stacktrace' fields and can therefore be combined using those
|
|
+ fields, however pointless that may be.
|
|
+
|
|
+ 'hist' triggers add a 'hist' file to each event's subdirectory.
|
|
+ Reading the 'hist' file for the event will dump the hash table in
|
|
+ its entirety to stdout. If there are multiple hist triggers
|
|
+ attached to an event, there will be a table for each trigger in the
|
|
+ output. The table displayed for a named trigger will be the same as
|
|
+ any other instance having the same name. Each printed hash table
|
|
+ entry is a simple list of the keys and values comprising the entry;
|
|
+ keys are printed first and are delineated by curly braces, and are
|
|
+ followed by the set of value fields for the entry. By default,
|
|
+ numeric fields are displayed as base-10 integers. This can be
|
|
+ modified by appending any of the following modifiers to the field
|
|
+ name:
|
|
+
|
|
+ .hex display a number as a hex value
|
|
+ .sym display an address as a symbol
|
|
+ .sym-offset display an address as a symbol and offset
|
|
+ .syscall display a syscall id as a system call name
|
|
+ .execname display a common_pid as a program name
|
|
+
|
|
+ Note that in general the semantics of a given field aren't
|
|
+ interpreted when applying a modifier to it, but there are some
|
|
+ restrictions to be aware of in this regard:
|
|
+
|
|
+ - only the 'hex' modifier can be used for values (because values
|
|
+ are essentially sums, and the other modifiers don't make sense
|
|
+ in that context).
|
|
+ - the 'execname' modifier can only be used on a 'common_pid'. The
|
|
+ reason for this is that the execname is simply the 'comm' value
|
|
+ saved for the 'current' process when an event was triggered,
|
|
+ which is the same as the common_pid value saved by the event
|
|
+ tracing code. Trying to apply that comm value to other pid
|
|
+ values wouldn't be correct, and typically events that care save
|
|
+ pid-specific comm fields in the event itself.
|
|
+
|
|
+ A typical usage scenario would be the following to enable a hist
|
|
+ trigger, read its current contents, and then turn it off:
|
|
+
|
|
+ # echo 'hist:keys=skbaddr.hex:vals=len' > \
|
|
+ /sys/kernel/debug/tracing/events/net/netif_rx/trigger
|
|
+
|
|
+ # cat /sys/kernel/debug/tracing/events/net/netif_rx/hist
|
|
+
|
|
+ # echo '!hist:keys=skbaddr.hex:vals=len' > \
|
|
+ /sys/kernel/debug/tracing/events/net/netif_rx/trigger
|
|
+
|
|
+ The trigger file itself can be read to show the details of the
|
|
+ currently attached hist trigger. This information is also displayed
|
|
+ at the top of the 'hist' file when read.
|
|
+
|
|
+ By default, the size of the hash table is 2048 entries. The 'size'
|
|
+ parameter can be used to specify more or fewer than that. The units
|
|
+ are in terms of hashtable entries - if a run uses more entries than
|
|
+ specified, the results will show the number of 'drops', the number
|
|
+ of hits that were ignored. The size should be a power of 2 between
|
|
+ 128 and 131072 (any non- power-of-2 number specified will be rounded
|
|
+ up).
|
|
+
|
|
+ The 'sort' parameter can be used to specify a value field to sort
|
|
+ on. The default if unspecified is 'hitcount' and the default sort
|
|
+ order is 'ascending'. To sort in the opposite direction, append
|
|
+ .descending' to the sort key.
|
|
+
|
|
+ The 'pause' parameter can be used to pause an existing hist trigger
|
|
+ or to start a hist trigger but not log any events until told to do
|
|
+ so. 'continue' or 'cont' can be used to start or restart a paused
|
|
+ hist trigger.
|
|
+
|
|
+ The 'clear' parameter will clear the contents of a running hist
|
|
+ trigger and leave its current paused/active state.
|
|
+
|
|
+ Note that the 'pause', 'cont', and 'clear' parameters should be
|
|
+ applied using 'append' shell operator ('>>') if applied to an
|
|
+ existing trigger, rather than via the '>' operator, which will cause
|
|
+ the trigger to be removed through truncation.
|
|
+
|
|
+- enable_hist/disable_hist
|
|
+
|
|
+ The enable_hist and disable_hist triggers can be used to have one
|
|
+ event conditionally start and stop another event's already-attached
|
|
+ hist trigger. Any number of enable_hist and disable_hist triggers
|
|
+ can be attached to a given event, allowing that event to kick off
|
|
+ and stop aggregations on a host of other events.
|
|
+
|
|
+ The format is very similar to the enable/disable_event triggers:
|
|
+
|
|
+ enable_hist:<system>:<event>[:count]
|
|
+ disable_hist:<system>:<event>[:count]
|
|
+
|
|
+ Instead of enabling or disabling the tracing of the target event
|
|
+ into the trace buffer as the enable/disable_event triggers do, the
|
|
+ enable/disable_hist triggers enable or disable the aggregation of
|
|
+ the target event into a hash table.
|
|
+
|
|
+ A typical usage scenario for the enable_hist/disable_hist triggers
|
|
+ would be to first set up a paused hist trigger on some event,
|
|
+ followed by an enable_hist/disable_hist pair that turns the hist
|
|
+ aggregation on and off when conditions of interest are hit:
|
|
+
|
|
+ # echo 'hist:keys=skbaddr.hex:vals=len:pause' > \
|
|
+ /sys/kernel/debug/tracing/events/net/netif_receive_skb/trigger
|
|
+
|
|
+ # echo 'enable_hist:net:netif_receive_skb if filename==/usr/bin/wget' > \
|
|
+ /sys/kernel/debug/tracing/events/sched/sched_process_exec/trigger
|
|
+
|
|
+ # echo 'disable_hist:net:netif_receive_skb if comm==wget' > \
|
|
+ /sys/kernel/debug/tracing/events/sched/sched_process_exit/trigger
|
|
+
|
|
+ The above sets up an initially paused hist trigger which is unpaused
|
|
+ and starts aggregating events when a given program is executed, and
|
|
+ which stops aggregating when the process exits and the hist trigger
|
|
+ is paused again.
|
|
+
|
|
+ The examples below provide a more concrete illustration of the
|
|
+ concepts and typical usage patterns discussed above.
|
|
+
|
|
+
|
|
+6.2 'hist' trigger examples
|
|
+---------------------------
|
|
+
|
|
+ The first set of examples creates aggregations using the kmalloc
|
|
+ event. The fields that can be used for the hist trigger are listed
|
|
+ in the kmalloc event's format file:
|
|
+
|
|
+ # cat /sys/kernel/debug/tracing/events/kmem/kmalloc/format
|
|
+ name: kmalloc
|
|
+ ID: 374
|
|
+ format:
|
|
+ field:unsigned short common_type; offset:0; size:2; signed:0;
|
|
+ field:unsigned char common_flags; offset:2; size:1; signed:0;
|
|
+ field:unsigned char common_preempt_count; offset:3; size:1; signed:0;
|
|
+ field:int common_pid; offset:4; size:4; signed:1;
|
|
+
|
|
+ field:unsigned long call_site; offset:8; size:8; signed:0;
|
|
+ field:const void * ptr; offset:16; size:8; signed:0;
|
|
+ field:size_t bytes_req; offset:24; size:8; signed:0;
|
|
+ field:size_t bytes_alloc; offset:32; size:8; signed:0;
|
|
+ field:gfp_t gfp_flags; offset:40; size:4; signed:0;
|
|
+
|
|
+ We'll start by creating a hist trigger that generates a simple table
|
|
+ that lists the total number of bytes requested for each function in
|
|
+ the kernel that made one or more calls to kmalloc:
|
|
+
|
|
+ # echo 'hist:key=call_site:val=bytes_req' > \
|
|
+ /sys/kernel/debug/tracing/events/kmem/kmalloc/trigger
|
|
+
|
|
+ This tells the tracing system to create a 'hist' trigger using the
|
|
+ call_site field of the kmalloc event as the key for the table, which
|
|
+ just means that each unique call_site address will have an entry
|
|
+ created for it in the table. The 'val=bytes_req' parameter tells
|
|
+ the hist trigger that for each unique entry (call_site) in the
|
|
+ table, it should keep a running total of the number of bytes
|
|
+ requested by that call_site.
|
|
+
|
|
+ We'll let it run for awhile and then dump the contents of the 'hist'
|
|
+ file in the kmalloc event's subdirectory (for readability, a number
|
|
+ of entries have been omitted):
|
|
+
|
|
+ # cat /sys/kernel/debug/tracing/events/kmem/kmalloc/hist
|
|
+ # trigger info: hist:keys=call_site:vals=bytes_req:sort=hitcount:size=2048 [active]
|
|
+
|
|
+ { call_site: 18446744072106379007 } hitcount: 1 bytes_req: 176
|
|
+ { call_site: 18446744071579557049 } hitcount: 1 bytes_req: 1024
|
|
+ { call_site: 18446744071580608289 } hitcount: 1 bytes_req: 16384
|
|
+ { call_site: 18446744071581827654 } hitcount: 1 bytes_req: 24
|
|
+ { call_site: 18446744071580700980 } hitcount: 1 bytes_req: 8
|
|
+ { call_site: 18446744071579359876 } hitcount: 1 bytes_req: 152
|
|
+ { call_site: 18446744071580795365 } hitcount: 3 bytes_req: 144
|
|
+ { call_site: 18446744071581303129 } hitcount: 3 bytes_req: 144
|
|
+ { call_site: 18446744071580713234 } hitcount: 4 bytes_req: 2560
|
|
+ { call_site: 18446744071580933750 } hitcount: 4 bytes_req: 736
|
|
+ .
|
|
+ .
|
|
+ .
|
|
+ { call_site: 18446744072106047046 } hitcount: 69 bytes_req: 5576
|
|
+ { call_site: 18446744071582116407 } hitcount: 73 bytes_req: 2336
|
|
+ { call_site: 18446744072106054684 } hitcount: 136 bytes_req: 140504
|
|
+ { call_site: 18446744072106224230 } hitcount: 136 bytes_req: 19584
|
|
+ { call_site: 18446744072106078074 } hitcount: 153 bytes_req: 2448
|
|
+ { call_site: 18446744072106062406 } hitcount: 153 bytes_req: 36720
|
|
+ { call_site: 18446744071582507929 } hitcount: 153 bytes_req: 37088
|
|
+ { call_site: 18446744072102520590 } hitcount: 273 bytes_req: 10920
|
|
+ { call_site: 18446744071582143559 } hitcount: 358 bytes_req: 716
|
|
+ { call_site: 18446744072106465852 } hitcount: 417 bytes_req: 56712
|
|
+ { call_site: 18446744072102523378 } hitcount: 485 bytes_req: 27160
|
|
+ { call_site: 18446744072099568646 } hitcount: 1676 bytes_req: 33520
|
|
+
|
|
+ Totals:
|
|
+ Hits: 4610
|
|
+ Entries: 45
|
|
+ Dropped: 0
|
|
+
|
|
+ The output displays a line for each entry, beginning with the key
|
|
+ specified in the trigger, followed by the value(s) also specified in
|
|
+ the trigger. At the beginning of the output is a line that displays
|
|
+ the trigger info, which can also be displayed by reading the
|
|
+ 'trigger' file:
|
|
+
|
|
+ # cat /sys/kernel/debug/tracing/events/kmem/kmalloc/trigger
|
|
+ hist:keys=call_site:vals=bytes_req:sort=hitcount:size=2048 [active]
|
|
+
|
|
+ At the end of the output are a few lines that display the overall
|
|
+ totals for the run. The 'Hits' field shows the total number of
|
|
+ times the event trigger was hit, the 'Entries' field shows the total
|
|
+ number of used entries in the hash table, and the 'Dropped' field
|
|
+ shows the number of hits that were dropped because the number of
|
|
+ used entries for the run exceeded the maximum number of entries
|
|
+ allowed for the table (normally 0, but if not a hint that you may
|
|
+ want to increase the size of the table using the 'size' parameter).
|
|
+
|
|
+ Notice in the above output that there's an extra field, 'hitcount',
|
|
+ which wasn't specified in the trigger. Also notice that in the
|
|
+ trigger info output, there's a parameter, 'sort=hitcount', which
|
|
+ wasn't specified in the trigger either. The reason for that is that
|
|
+ every trigger implicitly keeps a count of the total number of hits
|
|
+ attributed to a given entry, called the 'hitcount'. That hitcount
|
|
+ information is explicitly displayed in the output, and in the
|
|
+ absence of a user-specified sort parameter, is used as the default
|
|
+ sort field.
|
|
+
|
|
+ The value 'hitcount' can be used in place of an explicit value in
|
|
+ the 'values' parameter if you don't really need to have any
|
|
+ particular field summed and are mainly interested in hit
|
|
+ frequencies.
|
|
+
|
|
+ To turn the hist trigger off, simply call up the trigger in the
|
|
+ command history and re-execute it with a '!' prepended:
|
|
+
|
|
+ # echo '!hist:key=call_site:val=bytes_req' > \
|
|
+ /sys/kernel/debug/tracing/events/kmem/kmalloc/trigger
|
|
+
|
|
+ Finally, notice that the call_site as displayed in the output above
|
|
+ isn't really very useful. It's an address, but normally addresses
|
|
+ are displayed in hex. To have a numeric field displayed as a hex
|
|
+ value, simply append '.hex' to the field name in the trigger:
|
|
+
|
|
+ # echo 'hist:key=call_site.hex:val=bytes_req' > \
|
|
+ /sys/kernel/debug/tracing/events/kmem/kmalloc/trigger
|
|
+
|
|
+ # cat /sys/kernel/debug/tracing/events/kmem/kmalloc/hist
|
|
+ # trigger info: hist:keys=call_site.hex:vals=bytes_req:sort=hitcount:size=2048 [active]
|
|
+
|
|
+ { call_site: ffffffffa026b291 } hitcount: 1 bytes_req: 433
|
|
+ { call_site: ffffffffa07186ff } hitcount: 1 bytes_req: 176
|
|
+ { call_site: ffffffff811ae721 } hitcount: 1 bytes_req: 16384
|
|
+ { call_site: ffffffff811c5134 } hitcount: 1 bytes_req: 8
|
|
+ { call_site: ffffffffa04a9ebb } hitcount: 1 bytes_req: 511
|
|
+ { call_site: ffffffff8122e0a6 } hitcount: 1 bytes_req: 12
|
|
+ { call_site: ffffffff8107da84 } hitcount: 1 bytes_req: 152
|
|
+ { call_site: ffffffff812d8246 } hitcount: 1 bytes_req: 24
|
|
+ { call_site: ffffffff811dc1e5 } hitcount: 3 bytes_req: 144
|
|
+ { call_site: ffffffffa02515e8 } hitcount: 3 bytes_req: 648
|
|
+ { call_site: ffffffff81258159 } hitcount: 3 bytes_req: 144
|
|
+ { call_site: ffffffff811c80f4 } hitcount: 4 bytes_req: 544
|
|
+ .
|
|
+ .
|
|
+ .
|
|
+ { call_site: ffffffffa06c7646 } hitcount: 106 bytes_req: 8024
|
|
+ { call_site: ffffffffa06cb246 } hitcount: 132 bytes_req: 31680
|
|
+ { call_site: ffffffffa06cef7a } hitcount: 132 bytes_req: 2112
|
|
+ { call_site: ffffffff8137e399 } hitcount: 132 bytes_req: 23232
|
|
+ { call_site: ffffffffa06c941c } hitcount: 185 bytes_req: 171360
|
|
+ { call_site: ffffffffa06f2a66 } hitcount: 185 bytes_req: 26640
|
|
+ { call_site: ffffffffa036a70e } hitcount: 265 bytes_req: 10600
|
|
+ { call_site: ffffffff81325447 } hitcount: 292 bytes_req: 584
|
|
+ { call_site: ffffffffa072da3c } hitcount: 446 bytes_req: 60656
|
|
+ { call_site: ffffffffa036b1f2 } hitcount: 526 bytes_req: 29456
|
|
+ { call_site: ffffffffa0099c06 } hitcount: 1780 bytes_req: 35600
|
|
+
|
|
+ Totals:
|
|
+ Hits: 4775
|
|
+ Entries: 46
|
|
+ Dropped: 0
|
|
+
|
|
+ Even that's only marginally more useful - while hex values do look
|
|
+ more like addresses, what users are typically more interested in
|
|
+ when looking at text addresses are the corresponding symbols
|
|
+ instead. To have an address displayed as symbolic value instead,
|
|
+ simply append '.sym' or '.sym-offset' to the field name in the
|
|
+ trigger:
|
|
+
|
|
+ # echo 'hist:key=call_site.sym:val=bytes_req' > \
|
|
+ /sys/kernel/debug/tracing/events/kmem/kmalloc/trigger
|
|
+
|
|
+ # cat /sys/kernel/debug/tracing/events/kmem/kmalloc/hist
|
|
+ # trigger info: hist:keys=call_site.sym:vals=bytes_req:sort=hitcount:size=2048 [active]
|
|
+
|
|
+ { call_site: [ffffffff810adcb9] syslog_print_all } hitcount: 1 bytes_req: 1024
|
|
+ { call_site: [ffffffff8154bc62] usb_control_msg } hitcount: 1 bytes_req: 8
|
|
+ { call_site: [ffffffffa00bf6fe] hidraw_send_report [hid] } hitcount: 1 bytes_req: 7
|
|
+ { call_site: [ffffffff8154acbe] usb_alloc_urb } hitcount: 1 bytes_req: 192
|
|
+ { call_site: [ffffffffa00bf1ca] hidraw_report_event [hid] } hitcount: 1 bytes_req: 7
|
|
+ { call_site: [ffffffff811e3a25] __seq_open_private } hitcount: 1 bytes_req: 40
|
|
+ { call_site: [ffffffff8109524a] alloc_fair_sched_group } hitcount: 2 bytes_req: 128
|
|
+ { call_site: [ffffffff811febd5] fsnotify_alloc_group } hitcount: 2 bytes_req: 528
|
|
+ { call_site: [ffffffff81440f58] __tty_buffer_request_room } hitcount: 2 bytes_req: 2624
|
|
+ { call_site: [ffffffff81200ba6] inotify_new_group } hitcount: 2 bytes_req: 96
|
|
+ { call_site: [ffffffffa05e19af] ieee80211_start_tx_ba_session [mac80211] } hitcount: 2 bytes_req: 464
|
|
+ { call_site: [ffffffff81672406] tcp_get_metrics } hitcount: 2 bytes_req: 304
|
|
+ { call_site: [ffffffff81097ec2] alloc_rt_sched_group } hitcount: 2 bytes_req: 128
|
|
+ { call_site: [ffffffff81089b05] sched_create_group } hitcount: 2 bytes_req: 1424
|
|
+ .
|
|
+ .
|
|
+ .
|
|
+ { call_site: [ffffffffa04a580c] intel_crtc_page_flip [i915] } hitcount: 1185 bytes_req: 123240
|
|
+ { call_site: [ffffffffa0287592] drm_mode_page_flip_ioctl [drm] } hitcount: 1185 bytes_req: 104280
|
|
+ { call_site: [ffffffffa04c4a3c] intel_plane_duplicate_state [i915] } hitcount: 1402 bytes_req: 190672
|
|
+ { call_site: [ffffffff812891ca] ext4_find_extent } hitcount: 1518 bytes_req: 146208
|
|
+ { call_site: [ffffffffa029070e] drm_vma_node_allow [drm] } hitcount: 1746 bytes_req: 69840
|
|
+ { call_site: [ffffffffa045e7c4] i915_gem_do_execbuffer.isra.23 [i915] } hitcount: 2021 bytes_req: 792312
|
|
+ { call_site: [ffffffffa02911f2] drm_modeset_lock_crtc [drm] } hitcount: 2592 bytes_req: 145152
|
|
+ { call_site: [ffffffffa0489a66] intel_ring_begin [i915] } hitcount: 2629 bytes_req: 378576
|
|
+ { call_site: [ffffffffa046041c] i915_gem_execbuffer2 [i915] } hitcount: 2629 bytes_req: 3783248
|
|
+ { call_site: [ffffffff81325607] apparmor_file_alloc_security } hitcount: 5192 bytes_req: 10384
|
|
+ { call_site: [ffffffffa00b7c06] hid_report_raw_event [hid] } hitcount: 5529 bytes_req: 110584
|
|
+ { call_site: [ffffffff8131ebf7] aa_alloc_task_context } hitcount: 21943 bytes_req: 702176
|
|
+ { call_site: [ffffffff8125847d] ext4_htree_store_dirent } hitcount: 55759 bytes_req: 5074265
|
|
+
|
|
+ Totals:
|
|
+ Hits: 109928
|
|
+ Entries: 71
|
|
+ Dropped: 0
|
|
+
|
|
+ Because the default sort key above is 'hitcount', the above shows a
|
|
+ the list of call_sites by increasing hitcount, so that at the bottom
|
|
+ we see the functions that made the most kmalloc calls during the
|
|
+ run. If instead we we wanted to see the top kmalloc callers in
|
|
+ terms of the number of bytes requested rather than the number of
|
|
+ calls, and we wanted the top caller to appear at the top, we can use
|
|
+ the 'sort' parameter, along with the 'descending' modifier:
|
|
+
|
|
+ # echo 'hist:key=call_site.sym:val=bytes_req:sort=bytes_req.descending' > \
|
|
+ /sys/kernel/debug/tracing/events/kmem/kmalloc/trigger
|
|
+
|
|
+ # cat /sys/kernel/debug/tracing/events/kmem/kmalloc/hist
|
|
+ # trigger info: hist:keys=call_site.sym:vals=bytes_req:sort=bytes_req.descending:size=2048 [active]
|
|
+
|
|
+ { call_site: [ffffffffa046041c] i915_gem_execbuffer2 [i915] } hitcount: 2186 bytes_req: 3397464
|
|
+ { call_site: [ffffffffa045e7c4] i915_gem_do_execbuffer.isra.23 [i915] } hitcount: 1790 bytes_req: 712176
|
|
+ { call_site: [ffffffff8125847d] ext4_htree_store_dirent } hitcount: 8132 bytes_req: 513135
|
|
+ { call_site: [ffffffff811e2a1b] seq_buf_alloc } hitcount: 106 bytes_req: 440128
|
|
+ { call_site: [ffffffffa0489a66] intel_ring_begin [i915] } hitcount: 2186 bytes_req: 314784
|
|
+ { call_site: [ffffffff812891ca] ext4_find_extent } hitcount: 2174 bytes_req: 208992
|
|
+ { call_site: [ffffffff811ae8e1] __kmalloc } hitcount: 8 bytes_req: 131072
|
|
+ { call_site: [ffffffffa04c4a3c] intel_plane_duplicate_state [i915] } hitcount: 859 bytes_req: 116824
|
|
+ { call_site: [ffffffffa02911f2] drm_modeset_lock_crtc [drm] } hitcount: 1834 bytes_req: 102704
|
|
+ { call_site: [ffffffffa04a580c] intel_crtc_page_flip [i915] } hitcount: 972 bytes_req: 101088
|
|
+ { call_site: [ffffffffa0287592] drm_mode_page_flip_ioctl [drm] } hitcount: 972 bytes_req: 85536
|
|
+ { call_site: [ffffffffa00b7c06] hid_report_raw_event [hid] } hitcount: 3333 bytes_req: 66664
|
|
+ { call_site: [ffffffff8137e559] sg_kmalloc } hitcount: 209 bytes_req: 61632
|
|
+ .
|
|
+ .
|
|
+ .
|
|
+ { call_site: [ffffffff81095225] alloc_fair_sched_group } hitcount: 2 bytes_req: 128
|
|
+ { call_site: [ffffffff81097ec2] alloc_rt_sched_group } hitcount: 2 bytes_req: 128
|
|
+ { call_site: [ffffffff812d8406] copy_semundo } hitcount: 2 bytes_req: 48
|
|
+ { call_site: [ffffffff81200ba6] inotify_new_group } hitcount: 1 bytes_req: 48
|
|
+ { call_site: [ffffffffa027121a] drm_getmagic [drm] } hitcount: 1 bytes_req: 48
|
|
+ { call_site: [ffffffff811e3a25] __seq_open_private } hitcount: 1 bytes_req: 40
|
|
+ { call_site: [ffffffff811c52f4] bprm_change_interp } hitcount: 2 bytes_req: 16
|
|
+ { call_site: [ffffffff8154bc62] usb_control_msg } hitcount: 1 bytes_req: 8
|
|
+ { call_site: [ffffffffa00bf1ca] hidraw_report_event [hid] } hitcount: 1 bytes_req: 7
|
|
+ { call_site: [ffffffffa00bf6fe] hidraw_send_report [hid] } hitcount: 1 bytes_req: 7
|
|
+
|
|
+ Totals:
|
|
+ Hits: 32133
|
|
+ Entries: 81
|
|
+ Dropped: 0
|
|
+
|
|
+ To display the offset and size information in addition to the symbol
|
|
+ name, just use 'sym-offset' instead:
|
|
+
|
|
+ # echo 'hist:key=call_site.sym-offset:val=bytes_req:sort=bytes_req.descending' > \
|
|
+ /sys/kernel/debug/tracing/events/kmem/kmalloc/trigger
|
|
+
|
|
+ # cat /sys/kernel/debug/tracing/events/kmem/kmalloc/hist
|
|
+ # trigger info: hist:keys=call_site.sym-offset:vals=bytes_req:sort=bytes_req.descending:size=2048 [active]
|
|
+
|
|
+ { call_site: [ffffffffa046041c] i915_gem_execbuffer2+0x6c/0x2c0 [i915] } hitcount: 4569 bytes_req: 3163720
|
|
+ { call_site: [ffffffffa0489a66] intel_ring_begin+0xc6/0x1f0 [i915] } hitcount: 4569 bytes_req: 657936
|
|
+ { call_site: [ffffffffa045e7c4] i915_gem_do_execbuffer.isra.23+0x694/0x1020 [i915] } hitcount: 1519 bytes_req: 472936
|
|
+ { call_site: [ffffffffa045e646] i915_gem_do_execbuffer.isra.23+0x516/0x1020 [i915] } hitcount: 3050 bytes_req: 211832
|
|
+ { call_site: [ffffffff811e2a1b] seq_buf_alloc+0x1b/0x50 } hitcount: 34 bytes_req: 148384
|
|
+ { call_site: [ffffffffa04a580c] intel_crtc_page_flip+0xbc/0x870 [i915] } hitcount: 1385 bytes_req: 144040
|
|
+ { call_site: [ffffffff811ae8e1] __kmalloc+0x191/0x1b0 } hitcount: 8 bytes_req: 131072
|
|
+ { call_site: [ffffffffa0287592] drm_mode_page_flip_ioctl+0x282/0x360 [drm] } hitcount: 1385 bytes_req: 121880
|
|
+ { call_site: [ffffffffa02911f2] drm_modeset_lock_crtc+0x32/0x100 [drm] } hitcount: 1848 bytes_req: 103488
|
|
+ { call_site: [ffffffffa04c4a3c] intel_plane_duplicate_state+0x2c/0xa0 [i915] } hitcount: 461 bytes_req: 62696
|
|
+ { call_site: [ffffffffa029070e] drm_vma_node_allow+0x2e/0xd0 [drm] } hitcount: 1541 bytes_req: 61640
|
|
+ { call_site: [ffffffff815f8d7b] sk_prot_alloc+0xcb/0x1b0 } hitcount: 57 bytes_req: 57456
|
|
+ .
|
|
+ .
|
|
+ .
|
|
+ { call_site: [ffffffff8109524a] alloc_fair_sched_group+0x5a/0x1a0 } hitcount: 2 bytes_req: 128
|
|
+ { call_site: [ffffffffa027b921] drm_vm_open_locked+0x31/0xa0 [drm] } hitcount: 3 bytes_req: 96
|
|
+ { call_site: [ffffffff8122e266] proc_self_follow_link+0x76/0xb0 } hitcount: 8 bytes_req: 96
|
|
+ { call_site: [ffffffff81213e80] load_elf_binary+0x240/0x1650 } hitcount: 3 bytes_req: 84
|
|
+ { call_site: [ffffffff8154bc62] usb_control_msg+0x42/0x110 } hitcount: 1 bytes_req: 8
|
|
+ { call_site: [ffffffffa00bf6fe] hidraw_send_report+0x7e/0x1a0 [hid] } hitcount: 1 bytes_req: 7
|
|
+ { call_site: [ffffffffa00bf1ca] hidraw_report_event+0x8a/0x120 [hid] } hitcount: 1 bytes_req: 7
|
|
+
|
|
+ Totals:
|
|
+ Hits: 26098
|
|
+ Entries: 64
|
|
+ Dropped: 0
|
|
+
|
|
+ We can also add multiple fields to the 'values' parameter. For
|
|
+ example, we might want to see the total number of bytes allocated
|
|
+ alongside bytes requested, and display the result sorted by bytes
|
|
+ allocated in a descending order:
|
|
+
|
|
+ # echo 'hist:keys=call_site.sym:values=bytes_req,bytes_alloc:sort=bytes_alloc.descending' > \
|
|
+ /sys/kernel/debug/tracing/events/kmem/kmalloc/trigger
|
|
+
|
|
+ # cat /sys/kernel/debug/tracing/events/kmem/kmalloc/hist
|
|
+ # trigger info: hist:keys=call_site.sym:vals=bytes_req,bytes_alloc:sort=bytes_alloc.descending:size=2048 [active]
|
|
+
|
|
+ { call_site: [ffffffffa046041c] i915_gem_execbuffer2 [i915] } hitcount: 7403 bytes_req: 4084360 bytes_alloc: 5958016
|
|
+ { call_site: [ffffffff811e2a1b] seq_buf_alloc } hitcount: 541 bytes_req: 2213968 bytes_alloc: 2228224
|
|
+ { call_site: [ffffffffa0489a66] intel_ring_begin [i915] } hitcount: 7404 bytes_req: 1066176 bytes_alloc: 1421568
|
|
+ { call_site: [ffffffffa045e7c4] i915_gem_do_execbuffer.isra.23 [i915] } hitcount: 1565 bytes_req: 557368 bytes_alloc: 1037760
|
|
+ { call_site: [ffffffff8125847d] ext4_htree_store_dirent } hitcount: 9557 bytes_req: 595778 bytes_alloc: 695744
|
|
+ { call_site: [ffffffffa045e646] i915_gem_do_execbuffer.isra.23 [i915] } hitcount: 5839 bytes_req: 430680 bytes_alloc: 470400
|
|
+ { call_site: [ffffffffa04c4a3c] intel_plane_duplicate_state [i915] } hitcount: 2388 bytes_req: 324768 bytes_alloc: 458496
|
|
+ { call_site: [ffffffffa02911f2] drm_modeset_lock_crtc [drm] } hitcount: 3911 bytes_req: 219016 bytes_alloc: 250304
|
|
+ { call_site: [ffffffff815f8d7b] sk_prot_alloc } hitcount: 235 bytes_req: 236880 bytes_alloc: 240640
|
|
+ { call_site: [ffffffff8137e559] sg_kmalloc } hitcount: 557 bytes_req: 169024 bytes_alloc: 221760
|
|
+ { call_site: [ffffffffa00b7c06] hid_report_raw_event [hid] } hitcount: 9378 bytes_req: 187548 bytes_alloc: 206312
|
|
+ { call_site: [ffffffffa04a580c] intel_crtc_page_flip [i915] } hitcount: 1519 bytes_req: 157976 bytes_alloc: 194432
|
|
+ .
|
|
+ .
|
|
+ .
|
|
+ { call_site: [ffffffff8109bd3b] sched_autogroup_create_attach } hitcount: 2 bytes_req: 144 bytes_alloc: 192
|
|
+ { call_site: [ffffffff81097ee8] alloc_rt_sched_group } hitcount: 2 bytes_req: 128 bytes_alloc: 128
|
|
+ { call_site: [ffffffff8109524a] alloc_fair_sched_group } hitcount: 2 bytes_req: 128 bytes_alloc: 128
|
|
+ { call_site: [ffffffff81095225] alloc_fair_sched_group } hitcount: 2 bytes_req: 128 bytes_alloc: 128
|
|
+ { call_site: [ffffffff81097ec2] alloc_rt_sched_group } hitcount: 2 bytes_req: 128 bytes_alloc: 128
|
|
+ { call_site: [ffffffff81213e80] load_elf_binary } hitcount: 3 bytes_req: 84 bytes_alloc: 96
|
|
+ { call_site: [ffffffff81079a2e] kthread_create_on_node } hitcount: 1 bytes_req: 56 bytes_alloc: 64
|
|
+ { call_site: [ffffffffa00bf6fe] hidraw_send_report [hid] } hitcount: 1 bytes_req: 7 bytes_alloc: 8
|
|
+ { call_site: [ffffffff8154bc62] usb_control_msg } hitcount: 1 bytes_req: 8 bytes_alloc: 8
|
|
+ { call_site: [ffffffffa00bf1ca] hidraw_report_event [hid] } hitcount: 1 bytes_req: 7 bytes_alloc: 8
|
|
+
|
|
+ Totals:
|
|
+ Hits: 66598
|
|
+ Entries: 65
|
|
+ Dropped: 0
|
|
+
|
|
+ Finally, to finish off our kmalloc example, instead of simply having
|
|
+ the hist trigger display symbolic call_sites, we can have the hist
|
|
+ trigger additionally display the complete set of kernel stack traces
|
|
+ that led to each call_site. To do that, we simply use the special
|
|
+ value 'stacktrace' for the key parameter:
|
|
+
|
|
+ # echo 'hist:keys=stacktrace:values=bytes_req,bytes_alloc:sort=bytes_alloc' > \
|
|
+ /sys/kernel/debug/tracing/events/kmem/kmalloc/trigger
|
|
+
|
|
+ The above trigger will use the kernel stack trace in effect when an
|
|
+ event is triggered as the key for the hash table. This allows the
|
|
+ enumeration of every kernel callpath that led up to a particular
|
|
+ event, along with a running total of any of the event fields for
|
|
+ that event. Here we tally bytes requested and bytes allocated for
|
|
+ every callpath in the system that led up to a kmalloc (in this case
|
|
+ every callpath to a kmalloc for a kernel compile):
|
|
+
|
|
+ # cat /sys/kernel/debug/tracing/events/kmem/kmalloc/hist
|
|
+ # trigger info: hist:keys=stacktrace:vals=bytes_req,bytes_alloc:sort=bytes_alloc:size=2048 [active]
|
|
+
|
|
+ { stacktrace:
|
|
+ __kmalloc_track_caller+0x10b/0x1a0
|
|
+ kmemdup+0x20/0x50
|
|
+ hidraw_report_event+0x8a/0x120 [hid]
|
|
+ hid_report_raw_event+0x3ea/0x440 [hid]
|
|
+ hid_input_report+0x112/0x190 [hid]
|
|
+ hid_irq_in+0xc2/0x260 [usbhid]
|
|
+ __usb_hcd_giveback_urb+0x72/0x120
|
|
+ usb_giveback_urb_bh+0x9e/0xe0
|
|
+ tasklet_hi_action+0xf8/0x100
|
|
+ __do_softirq+0x114/0x2c0
|
|
+ irq_exit+0xa5/0xb0
|
|
+ do_IRQ+0x5a/0xf0
|
|
+ ret_from_intr+0x0/0x30
|
|
+ cpuidle_enter+0x17/0x20
|
|
+ cpu_startup_entry+0x315/0x3e0
|
|
+ rest_init+0x7c/0x80
|
|
+ } hitcount: 3 bytes_req: 21 bytes_alloc: 24
|
|
+ { stacktrace:
|
|
+ __kmalloc_track_caller+0x10b/0x1a0
|
|
+ kmemdup+0x20/0x50
|
|
+ hidraw_report_event+0x8a/0x120 [hid]
|
|
+ hid_report_raw_event+0x3ea/0x440 [hid]
|
|
+ hid_input_report+0x112/0x190 [hid]
|
|
+ hid_irq_in+0xc2/0x260 [usbhid]
|
|
+ __usb_hcd_giveback_urb+0x72/0x120
|
|
+ usb_giveback_urb_bh+0x9e/0xe0
|
|
+ tasklet_hi_action+0xf8/0x100
|
|
+ __do_softirq+0x114/0x2c0
|
|
+ irq_exit+0xa5/0xb0
|
|
+ do_IRQ+0x5a/0xf0
|
|
+ ret_from_intr+0x0/0x30
|
|
+ } hitcount: 3 bytes_req: 21 bytes_alloc: 24
|
|
+ { stacktrace:
|
|
+ kmem_cache_alloc_trace+0xeb/0x150
|
|
+ aa_alloc_task_context+0x27/0x40
|
|
+ apparmor_cred_prepare+0x1f/0x50
|
|
+ security_prepare_creds+0x16/0x20
|
|
+ prepare_creds+0xdf/0x1a0
|
|
+ SyS_capset+0xb5/0x200
|
|
+ system_call_fastpath+0x12/0x6a
|
|
+ } hitcount: 1 bytes_req: 32 bytes_alloc: 32
|
|
+ .
|
|
+ .
|
|
+ .
|
|
+ { stacktrace:
|
|
+ __kmalloc+0x11b/0x1b0
|
|
+ i915_gem_execbuffer2+0x6c/0x2c0 [i915]
|
|
+ drm_ioctl+0x349/0x670 [drm]
|
|
+ do_vfs_ioctl+0x2f0/0x4f0
|
|
+ SyS_ioctl+0x81/0xa0
|
|
+ system_call_fastpath+0x12/0x6a
|
|
+ } hitcount: 17726 bytes_req: 13944120 bytes_alloc: 19593808
|
|
+ { stacktrace:
|
|
+ __kmalloc+0x11b/0x1b0
|
|
+ load_elf_phdrs+0x76/0xa0
|
|
+ load_elf_binary+0x102/0x1650
|
|
+ search_binary_handler+0x97/0x1d0
|
|
+ do_execveat_common.isra.34+0x551/0x6e0
|
|
+ SyS_execve+0x3a/0x50
|
|
+ return_from_execve+0x0/0x23
|
|
+ } hitcount: 33348 bytes_req: 17152128 bytes_alloc: 20226048
|
|
+ { stacktrace:
|
|
+ kmem_cache_alloc_trace+0xeb/0x150
|
|
+ apparmor_file_alloc_security+0x27/0x40
|
|
+ security_file_alloc+0x16/0x20
|
|
+ get_empty_filp+0x93/0x1c0
|
|
+ path_openat+0x31/0x5f0
|
|
+ do_filp_open+0x3a/0x90
|
|
+ do_sys_open+0x128/0x220
|
|
+ SyS_open+0x1e/0x20
|
|
+ system_call_fastpath+0x12/0x6a
|
|
+ } hitcount: 4766422 bytes_req: 9532844 bytes_alloc: 38131376
|
|
+ { stacktrace:
|
|
+ __kmalloc+0x11b/0x1b0
|
|
+ seq_buf_alloc+0x1b/0x50
|
|
+ seq_read+0x2cc/0x370
|
|
+ proc_reg_read+0x3d/0x80
|
|
+ __vfs_read+0x28/0xe0
|
|
+ vfs_read+0x86/0x140
|
|
+ SyS_read+0x46/0xb0
|
|
+ system_call_fastpath+0x12/0x6a
|
|
+ } hitcount: 19133 bytes_req: 78368768 bytes_alloc: 78368768
|
|
+
|
|
+ Totals:
|
|
+ Hits: 6085872
|
|
+ Entries: 253
|
|
+ Dropped: 0
|
|
+
|
|
+ If you key a hist trigger on common_pid, in order for example to
|
|
+ gather and display sorted totals for each process, you can use the
|
|
+ special .execname modifier to display the executable names for the
|
|
+ processes in the table rather than raw pids. The example below
|
|
+ keeps a per-process sum of total bytes read:
|
|
+
|
|
+ # echo 'hist:key=common_pid.execname:val=count:sort=count.descending' > \
|
|
+ /sys/kernel/debug/tracing/events/syscalls/sys_enter_read/trigger
|
|
+
|
|
+ # cat /sys/kernel/debug/tracing/events/syscalls/sys_enter_read/hist
|
|
+ # trigger info: hist:keys=common_pid.execname:vals=count:sort=count.descending:size=2048 [active]
|
|
+
|
|
+ { common_pid: gnome-terminal [ 3196] } hitcount: 280 count: 1093512
|
|
+ { common_pid: Xorg [ 1309] } hitcount: 525 count: 256640
|
|
+ { common_pid: compiz [ 2889] } hitcount: 59 count: 254400
|
|
+ { common_pid: bash [ 8710] } hitcount: 3 count: 66369
|
|
+ { common_pid: dbus-daemon-lau [ 8703] } hitcount: 49 count: 47739
|
|
+ { common_pid: irqbalance [ 1252] } hitcount: 27 count: 27648
|
|
+ { common_pid: 01ifupdown [ 8705] } hitcount: 3 count: 17216
|
|
+ { common_pid: dbus-daemon [ 772] } hitcount: 10 count: 12396
|
|
+ { common_pid: Socket Thread [ 8342] } hitcount: 11 count: 11264
|
|
+ { common_pid: nm-dhcp-client. [ 8701] } hitcount: 6 count: 7424
|
|
+ { common_pid: gmain [ 1315] } hitcount: 18 count: 6336
|
|
+ .
|
|
+ .
|
|
+ .
|
|
+ { common_pid: postgres [ 1892] } hitcount: 2 count: 32
|
|
+ { common_pid: postgres [ 1891] } hitcount: 2 count: 32
|
|
+ { common_pid: gmain [ 8704] } hitcount: 2 count: 32
|
|
+ { common_pid: upstart-dbus-br [ 2740] } hitcount: 21 count: 21
|
|
+ { common_pid: nm-dispatcher.a [ 8696] } hitcount: 1 count: 16
|
|
+ { common_pid: indicator-datet [ 2904] } hitcount: 1 count: 16
|
|
+ { common_pid: gdbus [ 2998] } hitcount: 1 count: 16
|
|
+ { common_pid: rtkit-daemon [ 2052] } hitcount: 1 count: 8
|
|
+ { common_pid: init [ 1] } hitcount: 2 count: 2
|
|
+
|
|
+ Totals:
|
|
+ Hits: 2116
|
|
+ Entries: 51
|
|
+ Dropped: 0
|
|
+
|
|
+ Similarly, if you key a hist trigger on syscall id, for example to
|
|
+ gather and display a list of systemwide syscall hits, you can use
|
|
+ the special .syscall modifier to display the syscall names rather
|
|
+ than raw ids. The example below keeps a running total of syscall
|
|
+ counts for the system during the run:
|
|
+
|
|
+ # echo 'hist:key=id.syscall:val=hitcount' > \
|
|
+ /sys/kernel/debug/tracing/events/raw_syscalls/sys_enter/trigger
|
|
+
|
|
+ # cat /sys/kernel/debug/tracing/events/raw_syscalls/sys_enter/hist
|
|
+ # trigger info: hist:keys=id.syscall:vals=hitcount:sort=hitcount:size=2048 [active]
|
|
+
|
|
+ { id: sys_fsync [ 74] } hitcount: 1
|
|
+ { id: sys_newuname [ 63] } hitcount: 1
|
|
+ { id: sys_prctl [157] } hitcount: 1
|
|
+ { id: sys_statfs [137] } hitcount: 1
|
|
+ { id: sys_symlink [ 88] } hitcount: 1
|
|
+ { id: sys_sendmmsg [307] } hitcount: 1
|
|
+ { id: sys_semctl [ 66] } hitcount: 1
|
|
+ { id: sys_readlink [ 89] } hitcount: 3
|
|
+ { id: sys_bind [ 49] } hitcount: 3
|
|
+ { id: sys_getsockname [ 51] } hitcount: 3
|
|
+ { id: sys_unlink [ 87] } hitcount: 3
|
|
+ { id: sys_rename [ 82] } hitcount: 4
|
|
+ { id: unknown_syscall [ 58] } hitcount: 4
|
|
+ { id: sys_connect [ 42] } hitcount: 4
|
|
+ { id: sys_getpid [ 39] } hitcount: 4
|
|
+ .
|
|
+ .
|
|
+ .
|
|
+ { id: sys_rt_sigprocmask [ 14] } hitcount: 952
|
|
+ { id: sys_futex [202] } hitcount: 1534
|
|
+ { id: sys_write [ 1] } hitcount: 2689
|
|
+ { id: sys_setitimer [ 38] } hitcount: 2797
|
|
+ { id: sys_read [ 0] } hitcount: 3202
|
|
+ { id: sys_select [ 23] } hitcount: 3773
|
|
+ { id: sys_writev [ 20] } hitcount: 4531
|
|
+ { id: sys_poll [ 7] } hitcount: 8314
|
|
+ { id: sys_recvmsg [ 47] } hitcount: 13738
|
|
+ { id: sys_ioctl [ 16] } hitcount: 21843
|
|
+
|
|
+ Totals:
|
|
+ Hits: 67612
|
|
+ Entries: 72
|
|
+ Dropped: 0
|
|
+
|
|
+ The syscall counts above provide a rough overall picture of system
|
|
+ call activity on the system; we can see for example that the most
|
|
+ popular system call on this system was the 'sys_ioctl' system call.
|
|
+
|
|
+ We can use 'compound' keys to refine that number and provide some
|
|
+ further insight as to which processes exactly contribute to the
|
|
+ overall ioctl count.
|
|
+
|
|
+ The command below keeps a hitcount for every unique combination of
|
|
+ system call id and pid - the end result is essentially a table
|
|
+ that keeps a per-pid sum of system call hits. The results are
|
|
+ sorted using the system call id as the primary key, and the
|
|
+ hitcount sum as the secondary key:
|
|
+
|
|
+ # echo 'hist:key=id.syscall,common_pid.execname:val=hitcount:sort=id,hitcount' > \
|
|
+ /sys/kernel/debug/tracing/events/raw_syscalls/sys_enter/trigger
|
|
+
|
|
+ # cat /sys/kernel/debug/tracing/events/raw_syscalls/sys_enter/hist
|
|
+ # trigger info: hist:keys=id.syscall,common_pid.execname:vals=hitcount:sort=id.syscall,hitcount:size=2048 [active]
|
|
+
|
|
+ { id: sys_read [ 0], common_pid: rtkit-daemon [ 1877] } hitcount: 1
|
|
+ { id: sys_read [ 0], common_pid: gdbus [ 2976] } hitcount: 1
|
|
+ { id: sys_read [ 0], common_pid: console-kit-dae [ 3400] } hitcount: 1
|
|
+ { id: sys_read [ 0], common_pid: postgres [ 1865] } hitcount: 1
|
|
+ { id: sys_read [ 0], common_pid: deja-dup-monito [ 3543] } hitcount: 2
|
|
+ { id: sys_read [ 0], common_pid: NetworkManager [ 890] } hitcount: 2
|
|
+ { id: sys_read [ 0], common_pid: evolution-calen [ 3048] } hitcount: 2
|
|
+ { id: sys_read [ 0], common_pid: postgres [ 1864] } hitcount: 2
|
|
+ { id: sys_read [ 0], common_pid: nm-applet [ 3022] } hitcount: 2
|
|
+ { id: sys_read [ 0], common_pid: whoopsie [ 1212] } hitcount: 2
|
|
+ .
|
|
+ .
|
|
+ .
|
|
+ { id: sys_ioctl [ 16], common_pid: bash [ 8479] } hitcount: 1
|
|
+ { id: sys_ioctl [ 16], common_pid: bash [ 3472] } hitcount: 12
|
|
+ { id: sys_ioctl [ 16], common_pid: gnome-terminal [ 3199] } hitcount: 16
|
|
+ { id: sys_ioctl [ 16], common_pid: Xorg [ 1267] } hitcount: 1808
|
|
+ { id: sys_ioctl [ 16], common_pid: compiz [ 2994] } hitcount: 5580
|
|
+ .
|
|
+ .
|
|
+ .
|
|
+ { id: sys_waitid [247], common_pid: upstart-dbus-br [ 2690] } hitcount: 3
|
|
+ { id: sys_waitid [247], common_pid: upstart-dbus-br [ 2688] } hitcount: 16
|
|
+ { id: sys_inotify_add_watch [254], common_pid: gmain [ 975] } hitcount: 2
|
|
+ { id: sys_inotify_add_watch [254], common_pid: gmain [ 3204] } hitcount: 4
|
|
+ { id: sys_inotify_add_watch [254], common_pid: gmain [ 2888] } hitcount: 4
|
|
+ { id: sys_inotify_add_watch [254], common_pid: gmain [ 3003] } hitcount: 4
|
|
+ { id: sys_inotify_add_watch [254], common_pid: gmain [ 2873] } hitcount: 4
|
|
+ { id: sys_inotify_add_watch [254], common_pid: gmain [ 3196] } hitcount: 6
|
|
+ { id: sys_openat [257], common_pid: java [ 2623] } hitcount: 2
|
|
+ { id: sys_eventfd2 [290], common_pid: ibus-ui-gtk3 [ 2760] } hitcount: 4
|
|
+ { id: sys_eventfd2 [290], common_pid: compiz [ 2994] } hitcount: 6
|
|
+
|
|
+ Totals:
|
|
+ Hits: 31536
|
|
+ Entries: 323
|
|
+ Dropped: 0
|
|
+
|
|
+ The above list does give us a breakdown of the ioctl syscall by
|
|
+ pid, but it also gives us quite a bit more than that, which we
|
|
+ don't really care about at the moment. Since we know the syscall
|
|
+ id for sys_ioctl (16, displayed next to the sys_ioctl name), we
|
|
+ can use that to filter out all the other syscalls:
|
|
+
|
|
+ # echo 'hist:key=id.syscall,common_pid.execname:val=hitcount:sort=id,hitcount if id == 16' > \
|
|
+ /sys/kernel/debug/tracing/events/raw_syscalls/sys_enter/trigger
|
|
+
|
|
+ # cat /sys/kernel/debug/tracing/events/raw_syscalls/sys_enter/hist
|
|
+ # trigger info: hist:keys=id.syscall,common_pid.execname:vals=hitcount:sort=id.syscall,hitcount:size=2048 if id == 16 [active]
|
|
+
|
|
+ { id: sys_ioctl [ 16], common_pid: gmain [ 2769] } hitcount: 1
|
|
+ { id: sys_ioctl [ 16], common_pid: evolution-addre [ 8571] } hitcount: 1
|
|
+ { id: sys_ioctl [ 16], common_pid: gmain [ 3003] } hitcount: 1
|
|
+ { id: sys_ioctl [ 16], common_pid: gmain [ 2781] } hitcount: 1
|
|
+ { id: sys_ioctl [ 16], common_pid: gmain [ 2829] } hitcount: 1
|
|
+ { id: sys_ioctl [ 16], common_pid: bash [ 8726] } hitcount: 1
|
|
+ { id: sys_ioctl [ 16], common_pid: bash [ 8508] } hitcount: 1
|
|
+ { id: sys_ioctl [ 16], common_pid: gmain [ 2970] } hitcount: 1
|
|
+ { id: sys_ioctl [ 16], common_pid: gmain [ 2768] } hitcount: 1
|
|
+ .
|
|
+ .
|
|
+ .
|
|
+ { id: sys_ioctl [ 16], common_pid: pool [ 8559] } hitcount: 45
|
|
+ { id: sys_ioctl [ 16], common_pid: pool [ 8555] } hitcount: 48
|
|
+ { id: sys_ioctl [ 16], common_pid: pool [ 8551] } hitcount: 48
|
|
+ { id: sys_ioctl [ 16], common_pid: avahi-daemon [ 896] } hitcount: 66
|
|
+ { id: sys_ioctl [ 16], common_pid: Xorg [ 1267] } hitcount: 26674
|
|
+ { id: sys_ioctl [ 16], common_pid: compiz [ 2994] } hitcount: 73443
|
|
+
|
|
+ Totals:
|
|
+ Hits: 101162
|
|
+ Entries: 103
|
|
+ Dropped: 0
|
|
+
|
|
+ The above output shows that 'compiz' and 'Xorg' are far and away
|
|
+ the heaviest ioctl callers (which might lead to questions about
|
|
+ whether they really need to be making all those calls and to
|
|
+ possible avenues for further investigation.)
|
|
+
|
|
+ The compound key examples used a key and a sum value (hitcount) to
|
|
+ sort the output, but we can just as easily use two keys instead.
|
|
+ Here's an example where we use a compound key composed of the the
|
|
+ common_pid and size event fields. Sorting with pid as the primary
|
|
+ key and 'size' as the secondary key allows us to display an
|
|
+ ordered summary of the recvfrom sizes, with counts, received by
|
|
+ each process:
|
|
+
|
|
+ # echo 'hist:key=common_pid.execname,size:val=hitcount:sort=common_pid,size' > \
|
|
+ /sys/kernel/debug/tracing/events/syscalls/sys_enter_recvfrom/trigger
|
|
+
|
|
+ # cat /sys/kernel/debug/tracing/events/syscalls/sys_enter_recvfrom/hist
|
|
+ # trigger info: hist:keys=common_pid.execname,size:vals=hitcount:sort=common_pid.execname,size:size=2048 [active]
|
|
+
|
|
+ { common_pid: smbd [ 784], size: 4 } hitcount: 1
|
|
+ { common_pid: dnsmasq [ 1412], size: 4096 } hitcount: 672
|
|
+ { common_pid: postgres [ 1796], size: 1000 } hitcount: 6
|
|
+ { common_pid: postgres [ 1867], size: 1000 } hitcount: 10
|
|
+ { common_pid: bamfdaemon [ 2787], size: 28 } hitcount: 2
|
|
+ { common_pid: bamfdaemon [ 2787], size: 14360 } hitcount: 1
|
|
+ { common_pid: compiz [ 2994], size: 8 } hitcount: 1
|
|
+ { common_pid: compiz [ 2994], size: 20 } hitcount: 11
|
|
+ { common_pid: gnome-terminal [ 3199], size: 4 } hitcount: 2
|
|
+ { common_pid: firefox [ 8817], size: 4 } hitcount: 1
|
|
+ { common_pid: firefox [ 8817], size: 8 } hitcount: 5
|
|
+ { common_pid: firefox [ 8817], size: 588 } hitcount: 2
|
|
+ { common_pid: firefox [ 8817], size: 628 } hitcount: 1
|
|
+ { common_pid: firefox [ 8817], size: 6944 } hitcount: 1
|
|
+ { common_pid: firefox [ 8817], size: 408880 } hitcount: 2
|
|
+ { common_pid: firefox [ 8822], size: 8 } hitcount: 2
|
|
+ { common_pid: firefox [ 8822], size: 160 } hitcount: 2
|
|
+ { common_pid: firefox [ 8822], size: 320 } hitcount: 2
|
|
+ { common_pid: firefox [ 8822], size: 352 } hitcount: 1
|
|
+ .
|
|
+ .
|
|
+ .
|
|
+ { common_pid: pool [ 8923], size: 1960 } hitcount: 10
|
|
+ { common_pid: pool [ 8923], size: 2048 } hitcount: 10
|
|
+ { common_pid: pool [ 8924], size: 1960 } hitcount: 10
|
|
+ { common_pid: pool [ 8924], size: 2048 } hitcount: 10
|
|
+ { common_pid: pool [ 8928], size: 1964 } hitcount: 4
|
|
+ { common_pid: pool [ 8928], size: 1965 } hitcount: 2
|
|
+ { common_pid: pool [ 8928], size: 2048 } hitcount: 6
|
|
+ { common_pid: pool [ 8929], size: 1982 } hitcount: 1
|
|
+ { common_pid: pool [ 8929], size: 2048 } hitcount: 1
|
|
+
|
|
+ Totals:
|
|
+ Hits: 2016
|
|
+ Entries: 224
|
|
+ Dropped: 0
|
|
+
|
|
+ The above example also illustrates the fact that although a compound
|
|
+ key is treated as a single entity for hashing purposes, the sub-keys
|
|
+ it's composed of can be accessed independently.
|
|
+
|
|
+ The next example uses a string field as the hash key and
|
|
+ demonstrates how you can manually pause and continue a hist trigger.
|
|
+ In this example, we'll aggregate fork counts and don't expect a
|
|
+ large number of entries in the hash table, so we'll drop it to a
|
|
+ much smaller number, say 256:
|
|
+
|
|
+ # echo 'hist:key=child_comm:val=hitcount:size=256' > \
|
|
+ /sys/kernel/debug/tracing/events/sched/sched_process_fork/trigger
|
|
+
|
|
+ # cat /sys/kernel/debug/tracing/events/sched/sched_process_fork/hist
|
|
+ # trigger info: hist:keys=child_comm:vals=hitcount:sort=hitcount:size=256 [active]
|
|
+
|
|
+ { child_comm: dconf worker } hitcount: 1
|
|
+ { child_comm: ibus-daemon } hitcount: 1
|
|
+ { child_comm: whoopsie } hitcount: 1
|
|
+ { child_comm: smbd } hitcount: 1
|
|
+ { child_comm: gdbus } hitcount: 1
|
|
+ { child_comm: kthreadd } hitcount: 1
|
|
+ { child_comm: dconf worker } hitcount: 1
|
|
+ { child_comm: evolution-alarm } hitcount: 2
|
|
+ { child_comm: Socket Thread } hitcount: 2
|
|
+ { child_comm: postgres } hitcount: 2
|
|
+ { child_comm: bash } hitcount: 3
|
|
+ { child_comm: compiz } hitcount: 3
|
|
+ { child_comm: evolution-sourc } hitcount: 4
|
|
+ { child_comm: dhclient } hitcount: 4
|
|
+ { child_comm: pool } hitcount: 5
|
|
+ { child_comm: nm-dispatcher.a } hitcount: 8
|
|
+ { child_comm: firefox } hitcount: 8
|
|
+ { child_comm: dbus-daemon } hitcount: 8
|
|
+ { child_comm: glib-pacrunner } hitcount: 10
|
|
+ { child_comm: evolution } hitcount: 23
|
|
+
|
|
+ Totals:
|
|
+ Hits: 89
|
|
+ Entries: 20
|
|
+ Dropped: 0
|
|
+
|
|
+ If we want to pause the hist trigger, we can simply append :pause to
|
|
+ the command that started the trigger. Notice that the trigger info
|
|
+ displays as [paused]:
|
|
+
|
|
+ # echo 'hist:key=child_comm:val=hitcount:size=256:pause' >> \
|
|
+ /sys/kernel/debug/tracing/events/sched/sched_process_fork/trigger
|
|
+
|
|
+ # cat /sys/kernel/debug/tracing/events/sched/sched_process_fork/hist
|
|
+ # trigger info: hist:keys=child_comm:vals=hitcount:sort=hitcount:size=256 [paused]
|
|
+
|
|
+ { child_comm: dconf worker } hitcount: 1
|
|
+ { child_comm: kthreadd } hitcount: 1
|
|
+ { child_comm: dconf worker } hitcount: 1
|
|
+ { child_comm: gdbus } hitcount: 1
|
|
+ { child_comm: ibus-daemon } hitcount: 1
|
|
+ { child_comm: Socket Thread } hitcount: 2
|
|
+ { child_comm: evolution-alarm } hitcount: 2
|
|
+ { child_comm: smbd } hitcount: 2
|
|
+ { child_comm: bash } hitcount: 3
|
|
+ { child_comm: whoopsie } hitcount: 3
|
|
+ { child_comm: compiz } hitcount: 3
|
|
+ { child_comm: evolution-sourc } hitcount: 4
|
|
+ { child_comm: pool } hitcount: 5
|
|
+ { child_comm: postgres } hitcount: 6
|
|
+ { child_comm: firefox } hitcount: 8
|
|
+ { child_comm: dhclient } hitcount: 10
|
|
+ { child_comm: emacs } hitcount: 12
|
|
+ { child_comm: dbus-daemon } hitcount: 20
|
|
+ { child_comm: nm-dispatcher.a } hitcount: 20
|
|
+ { child_comm: evolution } hitcount: 35
|
|
+ { child_comm: glib-pacrunner } hitcount: 59
|
|
+
|
|
+ Totals:
|
|
+ Hits: 199
|
|
+ Entries: 21
|
|
+ Dropped: 0
|
|
+
|
|
+ To manually continue having the trigger aggregate events, append
|
|
+ :cont instead. Notice that the trigger info displays as [active]
|
|
+ again, and the data has changed:
|
|
+
|
|
+ # echo 'hist:key=child_comm:val=hitcount:size=256:cont' >> \
|
|
+ /sys/kernel/debug/tracing/events/sched/sched_process_fork/trigger
|
|
+
|
|
+ # cat /sys/kernel/debug/tracing/events/sched/sched_process_fork/hist
|
|
+ # trigger info: hist:keys=child_comm:vals=hitcount:sort=hitcount:size=256 [active]
|
|
+
|
|
+ { child_comm: dconf worker } hitcount: 1
|
|
+ { child_comm: dconf worker } hitcount: 1
|
|
+ { child_comm: kthreadd } hitcount: 1
|
|
+ { child_comm: gdbus } hitcount: 1
|
|
+ { child_comm: ibus-daemon } hitcount: 1
|
|
+ { child_comm: Socket Thread } hitcount: 2
|
|
+ { child_comm: evolution-alarm } hitcount: 2
|
|
+ { child_comm: smbd } hitcount: 2
|
|
+ { child_comm: whoopsie } hitcount: 3
|
|
+ { child_comm: compiz } hitcount: 3
|
|
+ { child_comm: evolution-sourc } hitcount: 4
|
|
+ { child_comm: bash } hitcount: 5
|
|
+ { child_comm: pool } hitcount: 5
|
|
+ { child_comm: postgres } hitcount: 6
|
|
+ { child_comm: firefox } hitcount: 8
|
|
+ { child_comm: dhclient } hitcount: 11
|
|
+ { child_comm: emacs } hitcount: 12
|
|
+ { child_comm: dbus-daemon } hitcount: 22
|
|
+ { child_comm: nm-dispatcher.a } hitcount: 22
|
|
+ { child_comm: evolution } hitcount: 35
|
|
+ { child_comm: glib-pacrunner } hitcount: 59
|
|
+
|
|
+ Totals:
|
|
+ Hits: 206
|
|
+ Entries: 21
|
|
+ Dropped: 0
|
|
+
|
|
+ The previous example showed how to start and stop a hist trigger by
|
|
+ appending 'pause' and 'continue' to the hist trigger command. A
|
|
+ hist trigger can also be started in a paused state by initially
|
|
+ starting the trigger with ':pause' appended. This allows you to
|
|
+ start the trigger only when you're ready to start collecting data
|
|
+ and not before. For example, you could start the trigger in a
|
|
+ paused state, then unpause it and do something you want to measure,
|
|
+ then pause the trigger again when done.
|
|
+
|
|
+ Of course, doing this manually can be difficult and error-prone, but
|
|
+ it is possible to automatically start and stop a hist trigger based
|
|
+ on some condition, via the enable_hist and disable_hist triggers.
|
|
+
|
|
+ For example, suppose we wanted to take a look at the relative
|
|
+ weights in terms of skb length for each callpath that leads to a
|
|
+ netif_receieve_skb event when downloading a decent-sized file using
|
|
+ wget.
|
|
+
|
|
+ First we set up an initially paused stacktrace trigger on the
|
|
+ netif_receive_skb event:
|
|
+
|
|
+ # echo 'hist:key=stacktrace:vals=len:pause' > \
|
|
+ /sys/kernel/debug/tracing/events/net/netif_receive_skb/trigger
|
|
+
|
|
+ Next, we set up an 'enable_hist' trigger on the sched_process_exec
|
|
+ event, with an 'if filename==/usr/bin/wget' filter. The effect of
|
|
+ this new trigger is that it will 'unpause' the hist trigger we just
|
|
+ set up on netif_receive_skb if and only if it sees a
|
|
+ sched_process_exec event with a filename of '/usr/bin/wget'. When
|
|
+ that happens, all netif_receive_skb events are aggregated into a
|
|
+ hash table keyed on stacktrace:
|
|
+
|
|
+ # echo 'enable_hist:net:netif_receive_skb if filename==/usr/bin/wget' > \
|
|
+ /sys/kernel/debug/tracing/events/sched/sched_process_exec/trigger
|
|
+
|
|
+ The aggregation continues until the netif_receive_skb is paused
|
|
+ again, which is what the following disable_hist event does by
|
|
+ creating a similar setup on the sched_process_exit event, using the
|
|
+ filter 'comm==wget':
|
|
+
|
|
+ # echo 'disable_hist:net:netif_receive_skb if comm==wget' > \
|
|
+ /sys/kernel/debug/tracing/events/sched/sched_process_exit/trigger
|
|
+
|
|
+ Whenever a process exits and the comm field of the disable_hist
|
|
+ trigger filter matches 'comm==wget', the netif_receive_skb hist
|
|
+ trigger is disabled.
|
|
+
|
|
+ The overall effect is that netif_receive_skb events are aggregated
|
|
+ into the hash table for only the duration of the wget. Executing a
|
|
+ wget command and then listing the 'hist' file will display the
|
|
+ output generated by the wget command:
|
|
+
|
|
+ $ wget https://www.kernel.org/pub/linux/kernel/v3.x/patch-3.19.xz
|
|
+
|
|
+ # cat /sys/kernel/debug/tracing/events/net/netif_receive_skb/hist
|
|
+ # trigger info: hist:keys=stacktrace:vals=len:sort=hitcount:size=2048 [paused]
|
|
+
|
|
+ { stacktrace:
|
|
+ __netif_receive_skb_core+0x46d/0x990
|
|
+ __netif_receive_skb+0x18/0x60
|
|
+ netif_receive_skb_internal+0x23/0x90
|
|
+ napi_gro_receive+0xc8/0x100
|
|
+ ieee80211_deliver_skb+0xd6/0x270 [mac80211]
|
|
+ ieee80211_rx_handlers+0xccf/0x22f0 [mac80211]
|
|
+ ieee80211_prepare_and_rx_handle+0x4e7/0xc40 [mac80211]
|
|
+ ieee80211_rx+0x31d/0x900 [mac80211]
|
|
+ iwlagn_rx_reply_rx+0x3db/0x6f0 [iwldvm]
|
|
+ iwl_rx_dispatch+0x8e/0xf0 [iwldvm]
|
|
+ iwl_pcie_irq_handler+0xe3c/0x12f0 [iwlwifi]
|
|
+ irq_thread_fn+0x20/0x50
|
|
+ irq_thread+0x11f/0x150
|
|
+ kthread+0xd2/0xf0
|
|
+ ret_from_fork+0x42/0x70
|
|
+ } hitcount: 85 len: 28884
|
|
+ { stacktrace:
|
|
+ __netif_receive_skb_core+0x46d/0x990
|
|
+ __netif_receive_skb+0x18/0x60
|
|
+ netif_receive_skb_internal+0x23/0x90
|
|
+ napi_gro_complete+0xa4/0xe0
|
|
+ dev_gro_receive+0x23a/0x360
|
|
+ napi_gro_receive+0x30/0x100
|
|
+ ieee80211_deliver_skb+0xd6/0x270 [mac80211]
|
|
+ ieee80211_rx_handlers+0xccf/0x22f0 [mac80211]
|
|
+ ieee80211_prepare_and_rx_handle+0x4e7/0xc40 [mac80211]
|
|
+ ieee80211_rx+0x31d/0x900 [mac80211]
|
|
+ iwlagn_rx_reply_rx+0x3db/0x6f0 [iwldvm]
|
|
+ iwl_rx_dispatch+0x8e/0xf0 [iwldvm]
|
|
+ iwl_pcie_irq_handler+0xe3c/0x12f0 [iwlwifi]
|
|
+ irq_thread_fn+0x20/0x50
|
|
+ irq_thread+0x11f/0x150
|
|
+ kthread+0xd2/0xf0
|
|
+ } hitcount: 98 len: 664329
|
|
+ { stacktrace:
|
|
+ __netif_receive_skb_core+0x46d/0x990
|
|
+ __netif_receive_skb+0x18/0x60
|
|
+ process_backlog+0xa8/0x150
|
|
+ net_rx_action+0x15d/0x340
|
|
+ __do_softirq+0x114/0x2c0
|
|
+ do_softirq_own_stack+0x1c/0x30
|
|
+ do_softirq+0x65/0x70
|
|
+ __local_bh_enable_ip+0xb5/0xc0
|
|
+ ip_finish_output+0x1f4/0x840
|
|
+ ip_output+0x6b/0xc0
|
|
+ ip_local_out_sk+0x31/0x40
|
|
+ ip_send_skb+0x1a/0x50
|
|
+ udp_send_skb+0x173/0x2a0
|
|
+ udp_sendmsg+0x2bf/0x9f0
|
|
+ inet_sendmsg+0x64/0xa0
|
|
+ sock_sendmsg+0x3d/0x50
|
|
+ } hitcount: 115 len: 13030
|
|
+ { stacktrace:
|
|
+ __netif_receive_skb_core+0x46d/0x990
|
|
+ __netif_receive_skb+0x18/0x60
|
|
+ netif_receive_skb_internal+0x23/0x90
|
|
+ napi_gro_complete+0xa4/0xe0
|
|
+ napi_gro_flush+0x6d/0x90
|
|
+ iwl_pcie_irq_handler+0x92a/0x12f0 [iwlwifi]
|
|
+ irq_thread_fn+0x20/0x50
|
|
+ irq_thread+0x11f/0x150
|
|
+ kthread+0xd2/0xf0
|
|
+ ret_from_fork+0x42/0x70
|
|
+ } hitcount: 934 len: 5512212
|
|
+
|
|
+ Totals:
|
|
+ Hits: 1232
|
|
+ Entries: 4
|
|
+ Dropped: 0
|
|
+
|
|
+ The above shows all the netif_receive_skb callpaths and their total
|
|
+ lengths for the duration of the wget command.
|
|
+
|
|
+ The 'clear' hist trigger param can be used to clear the hash table.
|
|
+ Suppose we wanted to try another run of the previous example but
|
|
+ this time also wanted to see the complete list of events that went
|
|
+ into the histogram. In order to avoid having to set everything up
|
|
+ again, we can just clear the histogram first:
|
|
+
|
|
+ # echo 'hist:key=stacktrace:vals=len:clear' >> \
|
|
+ /sys/kernel/debug/tracing/events/net/netif_receive_skb/trigger
|
|
+
|
|
+ Just to verify that it is in fact cleared, here's what we now see in
|
|
+ the hist file:
|
|
+
|
|
+ # cat /sys/kernel/debug/tracing/events/net/netif_receive_skb/hist
|
|
+ # trigger info: hist:keys=stacktrace:vals=len:sort=hitcount:size=2048 [paused]
|
|
+
|
|
+ Totals:
|
|
+ Hits: 0
|
|
+ Entries: 0
|
|
+ Dropped: 0
|
|
+
|
|
+ Since we want to see the detailed list of every netif_receive_skb
|
|
+ event occurring during the new run, which are in fact the same
|
|
+ events being aggregated into the hash table, we add some additional
|
|
+ 'enable_event' events to the triggering sched_process_exec and
|
|
+ sched_process_exit events as such:
|
|
+
|
|
+ # echo 'enable_event:net:netif_receive_skb if filename==/usr/bin/wget' > \
|
|
+ /sys/kernel/debug/tracing/events/sched/sched_process_exec/trigger
|
|
+
|
|
+ # echo 'disable_event:net:netif_receive_skb if comm==wget' > \
|
|
+ /sys/kernel/debug/tracing/events/sched/sched_process_exit/trigger
|
|
+
|
|
+ If you read the trigger files for the sched_process_exec and
|
|
+ sched_process_exit triggers, you should see two triggers for each:
|
|
+ one enabling/disabling the hist aggregation and the other
|
|
+ enabling/disabling the logging of events:
|
|
+
|
|
+ # cat /sys/kernel/debug/tracing/events/sched/sched_process_exec/trigger
|
|
+ enable_event:net:netif_receive_skb:unlimited if filename==/usr/bin/wget
|
|
+ enable_hist:net:netif_receive_skb:unlimited if filename==/usr/bin/wget
|
|
+
|
|
+ # cat /sys/kernel/debug/tracing/events/sched/sched_process_exit/trigger
|
|
+ enable_event:net:netif_receive_skb:unlimited if comm==wget
|
|
+ disable_hist:net:netif_receive_skb:unlimited if comm==wget
|
|
+
|
|
+ In other words, whenever either of the sched_process_exec or
|
|
+ sched_process_exit events is hit and matches 'wget', it enables or
|
|
+ disables both the histogram and the event log, and what you end up
|
|
+ with is a hash table and set of events just covering the specified
|
|
+ duration. Run the wget command again:
|
|
+
|
|
+ $ wget https://www.kernel.org/pub/linux/kernel/v3.x/patch-3.19.xz
|
|
+
|
|
+ Displaying the 'hist' file should show something similar to what you
|
|
+ saw in the last run, but this time you should also see the
|
|
+ individual events in the trace file:
|
|
+
|
|
+ # cat /sys/kernel/debug/tracing/trace
|
|
+
|
|
+ # tracer: nop
|
|
+ #
|
|
+ # entries-in-buffer/entries-written: 183/1426 #P:4
|
|
+ #
|
|
+ # _-----=> irqs-off
|
|
+ # / _----=> need-resched
|
|
+ # | / _---=> hardirq/softirq
|
|
+ # || / _--=> preempt-depth
|
|
+ # ||| / delay
|
|
+ # TASK-PID CPU# |||| TIMESTAMP FUNCTION
|
|
+ # | | | |||| | |
|
|
+ wget-15108 [000] ..s1 31769.606929: netif_receive_skb: dev=lo skbaddr=ffff88009c353100 len=60
|
|
+ wget-15108 [000] ..s1 31769.606999: netif_receive_skb: dev=lo skbaddr=ffff88009c353200 len=60
|
|
+ dnsmasq-1382 [000] ..s1 31769.677652: netif_receive_skb: dev=lo skbaddr=ffff88009c352b00 len=130
|
|
+ dnsmasq-1382 [000] ..s1 31769.685917: netif_receive_skb: dev=lo skbaddr=ffff88009c352200 len=138
|
|
+ ##### CPU 2 buffer started ####
|
|
+ irq/29-iwlwifi-559 [002] ..s. 31772.031529: netif_receive_skb: dev=wlan0 skbaddr=ffff88009d433d00 len=2948
|
|
+ irq/29-iwlwifi-559 [002] ..s. 31772.031572: netif_receive_skb: dev=wlan0 skbaddr=ffff88009d432200 len=1500
|
|
+ irq/29-iwlwifi-559 [002] ..s. 31772.032196: netif_receive_skb: dev=wlan0 skbaddr=ffff88009d433100 len=2948
|
|
+ irq/29-iwlwifi-559 [002] ..s. 31772.032761: netif_receive_skb: dev=wlan0 skbaddr=ffff88009d433000 len=2948
|
|
+ irq/29-iwlwifi-559 [002] ..s. 31772.033220: netif_receive_skb: dev=wlan0 skbaddr=ffff88009d432e00 len=1500
|
|
+ .
|
|
+ .
|
|
+ .
|
|
+
|
|
+ The following example demonstrates how multiple hist triggers can be
|
|
+ attached to a given event. This capability can be useful for
|
|
+ creating a set of different summaries derived from the same set of
|
|
+ events, or for comparing the effects of different filters, among
|
|
+ other things.
|
|
+
|
|
+ # echo 'hist:keys=skbaddr.hex:vals=len if len < 0' >> \
|
|
+ /sys/kernel/debug/tracing/events/net/netif_receive_skb/trigger
|
|
+ # echo 'hist:keys=skbaddr.hex:vals=len if len > 4096' >> \
|
|
+ /sys/kernel/debug/tracing/events/net/netif_receive_skb/trigger
|
|
+ # echo 'hist:keys=skbaddr.hex:vals=len if len == 256' >> \
|
|
+ /sys/kernel/debug/tracing/events/net/netif_receive_skb/trigger
|
|
+ # echo 'hist:keys=skbaddr.hex:vals=len' >> \
|
|
+ /sys/kernel/debug/tracing/events/net/netif_receive_skb/trigger
|
|
+ # echo 'hist:keys=len:vals=common_preempt_count' >> \
|
|
+ /sys/kernel/debug/tracing/events/net/netif_receive_skb/trigger
|
|
+
|
|
+ The above set of commands create four triggers differing only in
|
|
+ their filters, along with a completely different though fairly
|
|
+ nonsensical trigger. Note that in order to append multiple hist
|
|
+ triggers to the same file, you should use the '>>' operator to
|
|
+ append them ('>' will also add the new hist trigger, but will remove
|
|
+ any existing hist triggers beforehand).
|
|
+
|
|
+ Displaying the contents of the 'hist' file for the event shows the
|
|
+ contents of all five histograms:
|
|
+
|
|
+ # cat /sys/kernel/debug/tracing/events/net/netif_receive_skb/hist
|
|
+
|
|
+ # event histogram
|
|
+ #
|
|
+ # trigger info: hist:keys=len:vals=hitcount,common_preempt_count:sort=hitcount:size=2048 [active]
|
|
+ #
|
|
+
|
|
+ { len: 176 } hitcount: 1 common_preempt_count: 0
|
|
+ { len: 223 } hitcount: 1 common_preempt_count: 0
|
|
+ { len: 4854 } hitcount: 1 common_preempt_count: 0
|
|
+ { len: 395 } hitcount: 1 common_preempt_count: 0
|
|
+ { len: 177 } hitcount: 1 common_preempt_count: 0
|
|
+ { len: 446 } hitcount: 1 common_preempt_count: 0
|
|
+ { len: 1601 } hitcount: 1 common_preempt_count: 0
|
|
+ .
|
|
+ .
|
|
+ .
|
|
+ { len: 1280 } hitcount: 66 common_preempt_count: 0
|
|
+ { len: 116 } hitcount: 81 common_preempt_count: 40
|
|
+ { len: 708 } hitcount: 112 common_preempt_count: 0
|
|
+ { len: 46 } hitcount: 221 common_preempt_count: 0
|
|
+ { len: 1264 } hitcount: 458 common_preempt_count: 0
|
|
+
|
|
+ Totals:
|
|
+ Hits: 1428
|
|
+ Entries: 147
|
|
+ Dropped: 0
|
|
+
|
|
+
|
|
+ # event histogram
|
|
+ #
|
|
+ # trigger info: hist:keys=skbaddr.hex:vals=hitcount,len:sort=hitcount:size=2048 [active]
|
|
+ #
|
|
+
|
|
+ { skbaddr: ffff8800baee5e00 } hitcount: 1 len: 130
|
|
+ { skbaddr: ffff88005f3d5600 } hitcount: 1 len: 1280
|
|
+ { skbaddr: ffff88005f3d4900 } hitcount: 1 len: 1280
|
|
+ { skbaddr: ffff88009fed6300 } hitcount: 1 len: 115
|
|
+ { skbaddr: ffff88009fe0ad00 } hitcount: 1 len: 115
|
|
+ { skbaddr: ffff88008cdb1900 } hitcount: 1 len: 46
|
|
+ { skbaddr: ffff880064b5ef00 } hitcount: 1 len: 118
|
|
+ { skbaddr: ffff880044e3c700 } hitcount: 1 len: 60
|
|
+ { skbaddr: ffff880100065900 } hitcount: 1 len: 46
|
|
+ { skbaddr: ffff8800d46bd500 } hitcount: 1 len: 116
|
|
+ { skbaddr: ffff88005f3d5f00 } hitcount: 1 len: 1280
|
|
+ { skbaddr: ffff880100064700 } hitcount: 1 len: 365
|
|
+ { skbaddr: ffff8800badb6f00 } hitcount: 1 len: 60
|
|
+ .
|
|
+ .
|
|
+ .
|
|
+ { skbaddr: ffff88009fe0be00 } hitcount: 27 len: 24677
|
|
+ { skbaddr: ffff88009fe0a400 } hitcount: 27 len: 23052
|
|
+ { skbaddr: ffff88009fe0b700 } hitcount: 31 len: 25589
|
|
+ { skbaddr: ffff88009fe0b600 } hitcount: 32 len: 27326
|
|
+ { skbaddr: ffff88006a462800 } hitcount: 68 len: 71678
|
|
+ { skbaddr: ffff88006a463700 } hitcount: 70 len: 72678
|
|
+ { skbaddr: ffff88006a462b00 } hitcount: 71 len: 77589
|
|
+ { skbaddr: ffff88006a463600 } hitcount: 73 len: 71307
|
|
+ { skbaddr: ffff88006a462200 } hitcount: 81 len: 81032
|
|
+
|
|
+ Totals:
|
|
+ Hits: 1451
|
|
+ Entries: 318
|
|
+ Dropped: 0
|
|
+
|
|
+
|
|
+ # event histogram
|
|
+ #
|
|
+ # trigger info: hist:keys=skbaddr.hex:vals=hitcount,len:sort=hitcount:size=2048 if len == 256 [active]
|
|
+ #
|
|
+
|
|
+
|
|
+ Totals:
|
|
+ Hits: 0
|
|
+ Entries: 0
|
|
+ Dropped: 0
|
|
+
|
|
+
|
|
+ # event histogram
|
|
+ #
|
|
+ # trigger info: hist:keys=skbaddr.hex:vals=hitcount,len:sort=hitcount:size=2048 if len > 4096 [active]
|
|
+ #
|
|
+
|
|
+ { skbaddr: ffff88009fd2c300 } hitcount: 1 len: 7212
|
|
+ { skbaddr: ffff8800d2bcce00 } hitcount: 1 len: 7212
|
|
+ { skbaddr: ffff8800d2bcd700 } hitcount: 1 len: 7212
|
|
+ { skbaddr: ffff8800d2bcda00 } hitcount: 1 len: 21492
|
|
+ { skbaddr: ffff8800ae2e2d00 } hitcount: 1 len: 7212
|
|
+ { skbaddr: ffff8800d2bcdb00 } hitcount: 1 len: 7212
|
|
+ { skbaddr: ffff88006a4df500 } hitcount: 1 len: 4854
|
|
+ { skbaddr: ffff88008ce47b00 } hitcount: 1 len: 18636
|
|
+ { skbaddr: ffff8800ae2e2200 } hitcount: 1 len: 12924
|
|
+ { skbaddr: ffff88005f3e1000 } hitcount: 1 len: 4356
|
|
+ { skbaddr: ffff8800d2bcdc00 } hitcount: 2 len: 24420
|
|
+ { skbaddr: ffff8800d2bcc200 } hitcount: 2 len: 12996
|
|
+
|
|
+ Totals:
|
|
+ Hits: 14
|
|
+ Entries: 12
|
|
+ Dropped: 0
|
|
+
|
|
+
|
|
+ # event histogram
|
|
+ #
|
|
+ # trigger info: hist:keys=skbaddr.hex:vals=hitcount,len:sort=hitcount:size=2048 if len < 0 [active]
|
|
+ #
|
|
+
|
|
+
|
|
+ Totals:
|
|
+ Hits: 0
|
|
+ Entries: 0
|
|
+ Dropped: 0
|
|
+
|
|
+ Named triggers can be used to have triggers share a common set of
|
|
+ histogram data. This capability is mostly useful for combining the
|
|
+ output of events generated by tracepoints contained inside inline
|
|
+ functions, but names can be used in a hist trigger on any event.
|
|
+ For example, these two triggers when hit will update the same 'len'
|
|
+ field in the shared 'foo' histogram data:
|
|
+
|
|
+ # echo 'hist:name=foo:keys=skbaddr.hex:vals=len' > \
|
|
+ /sys/kernel/debug/tracing/events/net/netif_receive_skb/trigger
|
|
+ # echo 'hist:name=foo:keys=skbaddr.hex:vals=len' > \
|
|
+ /sys/kernel/debug/tracing/events/net/netif_rx/trigger
|
|
+
|
|
+ You can see that they're updating common histogram data by reading
|
|
+ each event's hist files at the same time:
|
|
+
|
|
+ # cat /sys/kernel/debug/tracing/events/net/netif_receive_skb/hist;
|
|
+ cat /sys/kernel/debug/tracing/events/net/netif_rx/hist
|
|
+
|
|
+ # event histogram
|
|
+ #
|
|
+ # trigger info: hist:name=foo:keys=skbaddr.hex:vals=hitcount,len:sort=hitcount:size=2048 [active]
|
|
+ #
|
|
+
|
|
+ { skbaddr: ffff88000ad53500 } hitcount: 1 len: 46
|
|
+ { skbaddr: ffff8800af5a1500 } hitcount: 1 len: 76
|
|
+ { skbaddr: ffff8800d62a1900 } hitcount: 1 len: 46
|
|
+ { skbaddr: ffff8800d2bccb00 } hitcount: 1 len: 468
|
|
+ { skbaddr: ffff8800d3c69900 } hitcount: 1 len: 46
|
|
+ { skbaddr: ffff88009ff09100 } hitcount: 1 len: 52
|
|
+ { skbaddr: ffff88010f13ab00 } hitcount: 1 len: 168
|
|
+ { skbaddr: ffff88006a54f400 } hitcount: 1 len: 46
|
|
+ { skbaddr: ffff8800d2bcc500 } hitcount: 1 len: 260
|
|
+ { skbaddr: ffff880064505000 } hitcount: 1 len: 46
|
|
+ { skbaddr: ffff8800baf24e00 } hitcount: 1 len: 32
|
|
+ { skbaddr: ffff88009fe0ad00 } hitcount: 1 len: 46
|
|
+ { skbaddr: ffff8800d3edff00 } hitcount: 1 len: 44
|
|
+ { skbaddr: ffff88009fe0b400 } hitcount: 1 len: 168
|
|
+ { skbaddr: ffff8800a1c55a00 } hitcount: 1 len: 40
|
|
+ { skbaddr: ffff8800d2bcd100 } hitcount: 1 len: 40
|
|
+ { skbaddr: ffff880064505f00 } hitcount: 1 len: 174
|
|
+ { skbaddr: ffff8800a8bff200 } hitcount: 1 len: 160
|
|
+ { skbaddr: ffff880044e3cc00 } hitcount: 1 len: 76
|
|
+ { skbaddr: ffff8800a8bfe700 } hitcount: 1 len: 46
|
|
+ { skbaddr: ffff8800d2bcdc00 } hitcount: 1 len: 32
|
|
+ { skbaddr: ffff8800a1f64800 } hitcount: 1 len: 46
|
|
+ { skbaddr: ffff8800d2bcde00 } hitcount: 1 len: 988
|
|
+ { skbaddr: ffff88006a5dea00 } hitcount: 1 len: 46
|
|
+ { skbaddr: ffff88002e37a200 } hitcount: 1 len: 44
|
|
+ { skbaddr: ffff8800a1f32c00 } hitcount: 2 len: 676
|
|
+ { skbaddr: ffff88000ad52600 } hitcount: 2 len: 107
|
|
+ { skbaddr: ffff8800a1f91e00 } hitcount: 2 len: 92
|
|
+ { skbaddr: ffff8800af5a0200 } hitcount: 2 len: 142
|
|
+ { skbaddr: ffff8800d2bcc600 } hitcount: 2 len: 220
|
|
+ { skbaddr: ffff8800ba36f500 } hitcount: 2 len: 92
|
|
+ { skbaddr: ffff8800d021f800 } hitcount: 2 len: 92
|
|
+ { skbaddr: ffff8800a1f33600 } hitcount: 2 len: 675
|
|
+ { skbaddr: ffff8800a8bfff00 } hitcount: 3 len: 138
|
|
+ { skbaddr: ffff8800d62a1300 } hitcount: 3 len: 138
|
|
+ { skbaddr: ffff88002e37a100 } hitcount: 4 len: 184
|
|
+ { skbaddr: ffff880064504400 } hitcount: 4 len: 184
|
|
+ { skbaddr: ffff8800a8bfec00 } hitcount: 4 len: 184
|
|
+ { skbaddr: ffff88000ad53700 } hitcount: 5 len: 230
|
|
+ { skbaddr: ffff8800d2bcdb00 } hitcount: 5 len: 196
|
|
+ { skbaddr: ffff8800a1f90000 } hitcount: 6 len: 276
|
|
+ { skbaddr: ffff88006a54f900 } hitcount: 6 len: 276
|
|
+
|
|
+ Totals:
|
|
+ Hits: 81
|
|
+ Entries: 42
|
|
+ Dropped: 0
|
|
+ # event histogram
|
|
+ #
|
|
+ # trigger info: hist:name=foo:keys=skbaddr.hex:vals=hitcount,len:sort=hitcount:size=2048 [active]
|
|
+ #
|
|
+
|
|
+ { skbaddr: ffff88000ad53500 } hitcount: 1 len: 46
|
|
+ { skbaddr: ffff8800af5a1500 } hitcount: 1 len: 76
|
|
+ { skbaddr: ffff8800d62a1900 } hitcount: 1 len: 46
|
|
+ { skbaddr: ffff8800d2bccb00 } hitcount: 1 len: 468
|
|
+ { skbaddr: ffff8800d3c69900 } hitcount: 1 len: 46
|
|
+ { skbaddr: ffff88009ff09100 } hitcount: 1 len: 52
|
|
+ { skbaddr: ffff88010f13ab00 } hitcount: 1 len: 168
|
|
+ { skbaddr: ffff88006a54f400 } hitcount: 1 len: 46
|
|
+ { skbaddr: ffff8800d2bcc500 } hitcount: 1 len: 260
|
|
+ { skbaddr: ffff880064505000 } hitcount: 1 len: 46
|
|
+ { skbaddr: ffff8800baf24e00 } hitcount: 1 len: 32
|
|
+ { skbaddr: ffff88009fe0ad00 } hitcount: 1 len: 46
|
|
+ { skbaddr: ffff8800d3edff00 } hitcount: 1 len: 44
|
|
+ { skbaddr: ffff88009fe0b400 } hitcount: 1 len: 168
|
|
+ { skbaddr: ffff8800a1c55a00 } hitcount: 1 len: 40
|
|
+ { skbaddr: ffff8800d2bcd100 } hitcount: 1 len: 40
|
|
+ { skbaddr: ffff880064505f00 } hitcount: 1 len: 174
|
|
+ { skbaddr: ffff8800a8bff200 } hitcount: 1 len: 160
|
|
+ { skbaddr: ffff880044e3cc00 } hitcount: 1 len: 76
|
|
+ { skbaddr: ffff8800a8bfe700 } hitcount: 1 len: 46
|
|
+ { skbaddr: ffff8800d2bcdc00 } hitcount: 1 len: 32
|
|
+ { skbaddr: ffff8800a1f64800 } hitcount: 1 len: 46
|
|
+ { skbaddr: ffff8800d2bcde00 } hitcount: 1 len: 988
|
|
+ { skbaddr: ffff88006a5dea00 } hitcount: 1 len: 46
|
|
+ { skbaddr: ffff88002e37a200 } hitcount: 1 len: 44
|
|
+ { skbaddr: ffff8800a1f32c00 } hitcount: 2 len: 676
|
|
+ { skbaddr: ffff88000ad52600 } hitcount: 2 len: 107
|
|
+ { skbaddr: ffff8800a1f91e00 } hitcount: 2 len: 92
|
|
+ { skbaddr: ffff8800af5a0200 } hitcount: 2 len: 142
|
|
+ { skbaddr: ffff8800d2bcc600 } hitcount: 2 len: 220
|
|
+ { skbaddr: ffff8800ba36f500 } hitcount: 2 len: 92
|
|
+ { skbaddr: ffff8800d021f800 } hitcount: 2 len: 92
|
|
+ { skbaddr: ffff8800a1f33600 } hitcount: 2 len: 675
|
|
+ { skbaddr: ffff8800a8bfff00 } hitcount: 3 len: 138
|
|
+ { skbaddr: ffff8800d62a1300 } hitcount: 3 len: 138
|
|
+ { skbaddr: ffff88002e37a100 } hitcount: 4 len: 184
|
|
+ { skbaddr: ffff880064504400 } hitcount: 4 len: 184
|
|
+ { skbaddr: ffff8800a8bfec00 } hitcount: 4 len: 184
|
|
+ { skbaddr: ffff88000ad53700 } hitcount: 5 len: 230
|
|
+ { skbaddr: ffff8800d2bcdb00 } hitcount: 5 len: 196
|
|
+ { skbaddr: ffff8800a1f90000 } hitcount: 6 len: 276
|
|
+ { skbaddr: ffff88006a54f900 } hitcount: 6 len: 276
|
|
+
|
|
+ Totals:
|
|
+ Hits: 81
|
|
+ Entries: 42
|
|
+ Dropped: 0
|
|
+
|
|
+ And here's an example that shows how to combine histogram data from
|
|
+ any two events even if they don't share any 'compatible' fields
|
|
+ other than 'hitcount' and 'stacktrace'. These commands create a
|
|
+ couple of triggers named 'bar' using those fields:
|
|
+
|
|
+ # echo 'hist:name=bar:key=stacktrace:val=hitcount' > \
|
|
+ /sys/kernel/debug/tracing/events/sched/sched_process_fork/trigger
|
|
+ # echo 'hist:name=bar:key=stacktrace:val=hitcount' > \
|
|
+ /sys/kernel/debug/tracing/events/net/netif_rx/trigger
|
|
+
|
|
+ And displaying the output of either shows some interesting if
|
|
+ somewhat confusing output:
|
|
+
|
|
+ # cat /sys/kernel/debug/tracing/events/sched/sched_process_fork/hist
|
|
+ # cat /sys/kernel/debug/tracing/events/net/netif_rx/hist
|
|
+
|
|
+ # event histogram
|
|
+ #
|
|
+ # trigger info: hist:name=bar:keys=stacktrace:vals=hitcount:sort=hitcount:size=2048 [active]
|
|
+ #
|
|
+
|
|
+ { stacktrace:
|
|
+ _do_fork+0x18e/0x330
|
|
+ kernel_thread+0x29/0x30
|
|
+ kthreadd+0x154/0x1b0
|
|
+ ret_from_fork+0x3f/0x70
|
|
+ } hitcount: 1
|
|
+ { stacktrace:
|
|
+ netif_rx_internal+0xb2/0xd0
|
|
+ netif_rx_ni+0x20/0x70
|
|
+ dev_loopback_xmit+0xaa/0xd0
|
|
+ ip_mc_output+0x126/0x240
|
|
+ ip_local_out_sk+0x31/0x40
|
|
+ igmp_send_report+0x1e9/0x230
|
|
+ igmp_timer_expire+0xe9/0x120
|
|
+ call_timer_fn+0x39/0xf0
|
|
+ run_timer_softirq+0x1e1/0x290
|
|
+ __do_softirq+0xfd/0x290
|
|
+ irq_exit+0x98/0xb0
|
|
+ smp_apic_timer_interrupt+0x4a/0x60
|
|
+ apic_timer_interrupt+0x6d/0x80
|
|
+ cpuidle_enter+0x17/0x20
|
|
+ call_cpuidle+0x3b/0x60
|
|
+ cpu_startup_entry+0x22d/0x310
|
|
+ } hitcount: 1
|
|
+ { stacktrace:
|
|
+ netif_rx_internal+0xb2/0xd0
|
|
+ netif_rx_ni+0x20/0x70
|
|
+ dev_loopback_xmit+0xaa/0xd0
|
|
+ ip_mc_output+0x17f/0x240
|
|
+ ip_local_out_sk+0x31/0x40
|
|
+ ip_send_skb+0x1a/0x50
|
|
+ udp_send_skb+0x13e/0x270
|
|
+ udp_sendmsg+0x2bf/0x980
|
|
+ inet_sendmsg+0x67/0xa0
|
|
+ sock_sendmsg+0x38/0x50
|
|
+ SYSC_sendto+0xef/0x170
|
|
+ SyS_sendto+0xe/0x10
|
|
+ entry_SYSCALL_64_fastpath+0x12/0x6a
|
|
+ } hitcount: 2
|
|
+ { stacktrace:
|
|
+ netif_rx_internal+0xb2/0xd0
|
|
+ netif_rx+0x1c/0x60
|
|
+ loopback_xmit+0x6c/0xb0
|
|
+ dev_hard_start_xmit+0x219/0x3a0
|
|
+ __dev_queue_xmit+0x415/0x4f0
|
|
+ dev_queue_xmit_sk+0x13/0x20
|
|
+ ip_finish_output2+0x237/0x340
|
|
+ ip_finish_output+0x113/0x1d0
|
|
+ ip_output+0x66/0xc0
|
|
+ ip_local_out_sk+0x31/0x40
|
|
+ ip_send_skb+0x1a/0x50
|
|
+ udp_send_skb+0x16d/0x270
|
|
+ udp_sendmsg+0x2bf/0x980
|
|
+ inet_sendmsg+0x67/0xa0
|
|
+ sock_sendmsg+0x38/0x50
|
|
+ ___sys_sendmsg+0x14e/0x270
|
|
+ } hitcount: 76
|
|
+ { stacktrace:
|
|
+ netif_rx_internal+0xb2/0xd0
|
|
+ netif_rx+0x1c/0x60
|
|
+ loopback_xmit+0x6c/0xb0
|
|
+ dev_hard_start_xmit+0x219/0x3a0
|
|
+ __dev_queue_xmit+0x415/0x4f0
|
|
+ dev_queue_xmit_sk+0x13/0x20
|
|
+ ip_finish_output2+0x237/0x340
|
|
+ ip_finish_output+0x113/0x1d0
|
|
+ ip_output+0x66/0xc0
|
|
+ ip_local_out_sk+0x31/0x40
|
|
+ ip_send_skb+0x1a/0x50
|
|
+ udp_send_skb+0x16d/0x270
|
|
+ udp_sendmsg+0x2bf/0x980
|
|
+ inet_sendmsg+0x67/0xa0
|
|
+ sock_sendmsg+0x38/0x50
|
|
+ ___sys_sendmsg+0x269/0x270
|
|
+ } hitcount: 77
|
|
+ { stacktrace:
|
|
+ netif_rx_internal+0xb2/0xd0
|
|
+ netif_rx+0x1c/0x60
|
|
+ loopback_xmit+0x6c/0xb0
|
|
+ dev_hard_start_xmit+0x219/0x3a0
|
|
+ __dev_queue_xmit+0x415/0x4f0
|
|
+ dev_queue_xmit_sk+0x13/0x20
|
|
+ ip_finish_output2+0x237/0x340
|
|
+ ip_finish_output+0x113/0x1d0
|
|
+ ip_output+0x66/0xc0
|
|
+ ip_local_out_sk+0x31/0x40
|
|
+ ip_send_skb+0x1a/0x50
|
|
+ udp_send_skb+0x16d/0x270
|
|
+ udp_sendmsg+0x2bf/0x980
|
|
+ inet_sendmsg+0x67/0xa0
|
|
+ sock_sendmsg+0x38/0x50
|
|
+ SYSC_sendto+0xef/0x170
|
|
+ } hitcount: 88
|
|
+ { stacktrace:
|
|
+ _do_fork+0x18e/0x330
|
|
+ SyS_clone+0x19/0x20
|
|
+ entry_SYSCALL_64_fastpath+0x12/0x6a
|
|
+ } hitcount: 244
|
|
+
|
|
+ Totals:
|
|
+ Hits: 489
|
|
+ Entries: 7
|
|
+ Dropped: 0
|