debian-packaging
/
linux
8
0
Fork 0
Code Releases Activity
linux/debian/patches/features/all/rt/mm-page_alloc-rt-friendly-p...

208 lines
5.7 KiB
Diff
Raw Blame History

From: Ingo Molnar <mingo@elte.hu>
Date: Fri, 3 Jul 2009 08:29:37 -0500
Subject: mm: page_alloc: rt-friendly per-cpu pages
Origin: https://www.kernel.org/pub/linux/kernel/projects/rt/4.4/patches-4.4-rt3.tar.xz
rt-friendly per-cpu pages: convert the irqs-off per-cpu locking
method into a preemptible, explicit-per-cpu-locks method.
Contains fixes from:
Peter Zijlstra <a.p.zijlstra@chello.nl>
Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---
mm/page_alloc.c | 57 ++++++++++++++++++++++++++++++++++++++++----------------
1 file changed, 41 insertions(+), 16 deletions(-)
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -60,6 +60,7 @@
#include <linux/page_ext.h>
#include <linux/hugetlb.h>
#include <linux/sched/rt.h>
+#include <linux/locallock.h>
#include <linux/page_owner.h>
#include <linux/kthread.h>
@@ -264,6 +265,18 @@ EXPORT_SYMBOL(nr_node_ids);
EXPORT_SYMBOL(nr_online_nodes);
#endif
+static DEFINE_LOCAL_IRQ_LOCK(pa_lock);
+
+#ifdef CONFIG_PREEMPT_RT_BASE
+# define cpu_lock_irqsave(cpu, flags) \
+ spin_lock_irqsave(&per_cpu(pa_lock, cpu).lock, flags)
+# define cpu_unlock_irqrestore(cpu, flags) \
+ spin_unlock_irqrestore(&per_cpu(pa_lock, cpu).lock, flags)
+#else
+# define cpu_lock_irqsave(cpu, flags) local_irq_save(flags)
+# define cpu_unlock_irqrestore(cpu, flags) local_irq_restore(flags)
+#endif
+
int page_group_by_mobility_disabled __read_mostly;
#ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT
@@ -997,10 +1010,10 @@ static void __free_pages_ok(struct page
return;
migratetype = get_pfnblock_migratetype(page, pfn);
- local_irq_save(flags);
+ local_lock_irqsave(pa_lock, flags);
__count_vm_events(PGFREE, 1 << order);
free_one_page(page_zone(page), page, pfn, order, migratetype);
- local_irq_restore(flags);
+ local_unlock_irqrestore(pa_lock, flags);
}
static void __init __free_pages_boot_core(struct page *page,
@@ -1859,14 +1872,14 @@ void drain_zone_pages(struct zone *zone,
unsigned long flags;
int to_drain, batch;
- local_irq_save(flags);
+ local_lock_irqsave(pa_lock, flags);
batch = READ_ONCE(pcp->batch);
to_drain = min(pcp->count, batch);
if (to_drain > 0) {
free_pcppages_bulk(zone, to_drain, pcp);
pcp->count -= to_drain;
}
- local_irq_restore(flags);
+ local_unlock_irqrestore(pa_lock, flags);
}
#endif
@@ -1883,7 +1896,7 @@ static void drain_pages_zone(unsigned in
struct per_cpu_pageset *pset;
struct per_cpu_pages *pcp;
- local_irq_save(flags);
+ cpu_lock_irqsave(cpu, flags);
pset = per_cpu_ptr(zone->pageset, cpu);
pcp = &pset->pcp;
@@ -1891,7 +1904,7 @@ static void drain_pages_zone(unsigned in
free_pcppages_bulk(zone, pcp->count, pcp);
pcp->count = 0;
}
- local_irq_restore(flags);
+ cpu_unlock_irqrestore(cpu, flags);
}
/*
@@ -1977,8 +1990,17 @@ void drain_all_pages(struct zone *zone)
else
cpumask_clear_cpu(cpu, &cpus_with_pcps);
}
+#ifndef CONFIG_PREEMPT_RT_BASE
on_each_cpu_mask(&cpus_with_pcps, (smp_call_func_t) drain_local_pages,
zone, 1);
+#else
+ for_each_cpu(cpu, &cpus_with_pcps) {
+ if (zone)
+ drain_pages_zone(cpu, zone);
+ else
+ drain_pages(cpu);
+ }
+#endif
}
#ifdef CONFIG_HIBERNATION
@@ -2034,7 +2056,7 @@ void free_hot_cold_page(struct page *pag
migratetype = get_pfnblock_migratetype(page, pfn);
set_pcppage_migratetype(page, migratetype);
- local_irq_save(flags);
+ local_lock_irqsave(pa_lock, flags);
__count_vm_event(PGFREE);
/*
@@ -2065,7 +2087,7 @@ void free_hot_cold_page(struct page *pag
}
out:
- local_irq_restore(flags);
+ local_unlock_irqrestore(pa_lock, flags);
}
/*
@@ -2200,7 +2222,7 @@ struct page *buffered_rmqueue(struct zon
struct per_cpu_pages *pcp;
struct list_head *list;
- local_irq_save(flags);
+ local_lock_irqsave(pa_lock, flags);
pcp = &this_cpu_ptr(zone->pageset)->pcp;
list = &pcp->lists[migratetype];
if (list_empty(list)) {
@@ -2232,7 +2254,7 @@ struct page *buffered_rmqueue(struct zon
*/
WARN_ON_ONCE(order > 1);
}
- spin_lock_irqsave(&zone->lock, flags);
+ local_spin_lock_irqsave(pa_lock, &zone->lock, flags);
page = NULL;
if (alloc_flags & ALLOC_HARDER) {
@@ -2242,11 +2264,13 @@ struct page *buffered_rmqueue(struct zon
}
if (!page)
page = __rmqueue(zone, order, migratetype, gfp_flags);
- spin_unlock(&zone->lock);
- if (!page)
+ if (!page) {
+ spin_unlock(&zone->lock);
goto failed;
+ }
__mod_zone_freepage_state(zone, -(1 << order),
get_pcppage_migratetype(page));
+ spin_unlock(&zone->lock);
}
__mod_zone_page_state(zone, NR_ALLOC_BATCH, -(1 << order));
@@ -2256,13 +2280,13 @@ struct page *buffered_rmqueue(struct zon
__count_zone_vm_events(PGALLOC, zone, 1 << order);
zone_statistics(preferred_zone, zone, gfp_flags);
- local_irq_restore(flags);
+ local_unlock_irqrestore(pa_lock, flags);
VM_BUG_ON_PAGE(bad_range(zone, page), page);
return page;
failed:
- local_irq_restore(flags);
+ local_unlock_irqrestore(pa_lock, flags);
return NULL;
}
@@ -5928,6 +5952,7 @@ static int page_alloc_cpu_notify(struct
void __init page_alloc_init(void)
{
hotcpu_notifier(page_alloc_cpu_notify, 0);
+ local_irq_lock_init(pa_lock);
}
/*
@@ -6822,7 +6847,7 @@ void zone_pcp_reset(struct zone *zone)
struct per_cpu_pageset *pset;
/* avoid races with drain_pages() */
- local_irq_save(flags);
+ local_lock_irqsave(pa_lock, flags);
if (zone->pageset != &boot_pageset) {
for_each_online_cpu(cpu) {
pset = per_cpu_ptr(zone->pageset, cpu);
@@ -6831,7 +6856,7 @@ void zone_pcp_reset(struct zone *zone)
free_percpu(zone->pageset);
zone->pageset = &boot_pageset;
}
- local_irq_restore(flags);
+ local_unlock_irqrestore(pa_lock, flags);
}
#ifdef CONFIG_MEMORY_HOTREMOVE
View Git Blame Copy Permalink