Subject: mm: pagefault_disabled() From: Peter Zijlstra Date: Thu Aug 11 15:31:31 CEST 2011 Origin: https://www.kernel.org/pub/linux/kernel/projects/rt/3.14/patches-3.14.10-rt7.tar.xz Wrap the test for pagefault_disabled() into a helper, this allows us to remove the need for current->pagefault_disabled on !-rt kernels. Signed-off-by: Peter Zijlstra Link: http://lkml.kernel.org/n/tip-3yy517m8zsi9fpsf14xfaqkw@git.kernel.org --- arch/alpha/mm/fault.c | 2 +- arch/arm/mm/fault.c | 2 +- arch/avr32/mm/fault.c | 3 +-- arch/cris/mm/fault.c | 2 +- arch/frv/mm/fault.c | 2 +- arch/ia64/mm/fault.c | 2 +- arch/m32r/mm/fault.c | 2 +- arch/m68k/mm/fault.c | 2 +- arch/microblaze/mm/fault.c | 2 +- arch/mips/mm/fault.c | 2 +- arch/mn10300/mm/fault.c | 2 +- arch/parisc/mm/fault.c | 2 +- arch/powerpc/mm/fault.c | 2 +- arch/s390/mm/fault.c | 4 ++-- arch/score/mm/fault.c | 2 +- arch/sh/mm/fault.c | 2 +- arch/sparc/mm/fault_32.c | 2 +- arch/sparc/mm/fault_64.c | 2 +- arch/tile/mm/fault.c | 2 +- arch/um/kernel/trap.c | 2 +- arch/x86/mm/fault.c | 2 +- arch/xtensa/mm/fault.c | 2 +- include/linux/sched.h | 14 ++++++++++++++ kernel/fork.c | 2 ++ 24 files changed, 39 insertions(+), 24 deletions(-) --- a/arch/alpha/mm/fault.c +++ b/arch/alpha/mm/fault.c @@ -107,7 +107,7 @@ do_page_fault(unsigned long address, uns /* If we're in an interrupt context, or have no user context, we must not take the fault. */ - if (!mm || in_atomic() || current->pagefault_disabled) + if (!mm || pagefault_disabled()) goto no_context; #ifdef CONFIG_ALPHA_LARGE_VMALLOC --- a/arch/arm/mm/fault.c +++ b/arch/arm/mm/fault.c @@ -277,7 +277,7 @@ do_page_fault(unsigned long addr, unsign * If we're in an interrupt or have no user * context, we must not take the fault.. */ - if (in_atomic() || !mm || current->pagefault_disabled) + if (!mm || pagefault_disabled()) goto no_context; if (user_mode(regs)) --- a/arch/avr32/mm/fault.c +++ b/arch/avr32/mm/fault.c @@ -81,8 +81,7 @@ asmlinkage void do_page_fault(unsigned l * If we're in an interrupt or have no user context, we must * not take the fault... */ - if (in_atomic() || !mm || regs->sr & SYSREG_BIT(GM) || - current->pagefault_disabled) + if (!mm || regs->sr & SYSREG_BIT(GM) || pagefault_disabled()) goto no_context; local_irq_enable(); --- a/arch/cris/mm/fault.c +++ b/arch/cris/mm/fault.c @@ -113,7 +113,7 @@ do_page_fault(unsigned long address, str * user context, we must not take the fault. */ - if (in_atomic() || !mm || current->pagefault_disabled) + if (!mm || pagefault_disabled()) goto no_context; if (user_mode(regs)) --- a/arch/frv/mm/fault.c +++ b/arch/frv/mm/fault.c @@ -78,7 +78,7 @@ asmlinkage void do_page_fault(int datamm * If we're in an interrupt or have no user * context, we must not take the fault.. */ - if (in_atomic() || !mm || current->pagefault_disabled) + if (!mm || pagefault_disabled()) goto no_context; if (user_mode(__frame)) --- a/arch/ia64/mm/fault.c +++ b/arch/ia64/mm/fault.c @@ -96,7 +96,7 @@ ia64_do_page_fault (unsigned long addres /* * If we're in an interrupt or have no user context, we must not take the fault.. */ - if (in_atomic() || !mm || current->pagefault_disabled) + if (!mm || pagefault_disabled()) goto no_context; #ifdef CONFIG_VIRTUAL_MEM_MAP --- a/arch/m32r/mm/fault.c +++ b/arch/m32r/mm/fault.c @@ -114,7 +114,7 @@ asmlinkage void do_page_fault(struct pt_ * If we're in an interrupt or have no user context or are running in an * atomic region then we must not take the fault.. */ - if (in_atomic() || !mm || current->pagefault_disabled + if (!mm || pagefault_disabled()) goto bad_area_nosemaphore; if (error_code & ACE_USERMODE) --- a/arch/m68k/mm/fault.c +++ b/arch/m68k/mm/fault.c @@ -81,7 +81,7 @@ int do_page_fault(struct pt_regs *regs, * If we're in an interrupt or have no user * context, we must not take the fault.. */ - if (in_atomic() || !mm || current->pagefault_disabled) + if (!mm || pagefault_disabled()) goto no_context; if (user_mode(regs)) --- a/arch/microblaze/mm/fault.c +++ b/arch/microblaze/mm/fault.c @@ -107,7 +107,7 @@ void do_page_fault(struct pt_regs *regs, if ((error_code & 0x13) == 0x13 || (error_code & 0x11) == 0x11) is_write = 0; - if (unlikely(in_atomic() || !mm || current->pagefault_disabled)) { + if (unlikely(!mm || pagefault_disabled())) { if (kernel_mode(regs)) goto bad_area_nosemaphore; --- a/arch/mips/mm/fault.c +++ b/arch/mips/mm/fault.c @@ -89,7 +89,7 @@ static void __kprobes __do_page_fault(st * If we're in an interrupt or have no user * context, we must not take the fault.. */ - if (in_atomic() || !mm || current->pagefault_disabled) + if (!mm || pagefault_disabled()) goto bad_area_nosemaphore; if (user_mode(regs)) --- a/arch/mn10300/mm/fault.c +++ b/arch/mn10300/mm/fault.c @@ -168,7 +168,7 @@ asmlinkage void do_page_fault(struct pt_ * If we're in an interrupt or have no user * context, we must not take the fault.. */ - if (in_atomic() || !mm || current->pagefault_disabled) + if (!mm || pagefault_disabled()) goto no_context; if ((fault_code & MMUFCR_xFC_ACCESS) == MMUFCR_xFC_ACCESS_USR) --- a/arch/parisc/mm/fault.c +++ b/arch/parisc/mm/fault.c @@ -183,7 +183,7 @@ void do_page_fault(struct pt_regs *regs, int fault; unsigned int flags; - if (in_atomic() || current->pagefault_disabled) + if (pagefault_disabled()) goto no_context; tsk = current; --- a/arch/powerpc/mm/fault.c +++ b/arch/powerpc/mm/fault.c @@ -261,7 +261,7 @@ int __kprobes do_page_fault(struct pt_re if (!arch_irq_disabled_regs(regs)) local_irq_enable(); - if (in_atomic() || mm == NULL || current->pagefault_disabled) { + if (in_atomic() || mm == NULL || pagefault_disabled()) { if (!user_mode(regs)) { rc = SIGSEGV; goto bail; --- a/arch/s390/mm/fault.c +++ b/arch/s390/mm/fault.c @@ -291,8 +291,8 @@ static inline int do_exception(struct pt * user context. */ fault = VM_FAULT_BADCONTEXT; - if (unlikely(!user_space_fault(trans_exc_code) || in_atomic() || !mm || - tsk->pagefault_disabled)) + if (unlikely(!user_space_fault(trans_exc_code) || + !mm || pagefault_disabled())) goto out; address = trans_exc_code & __FAIL_ADDR_MASK; --- a/arch/score/mm/fault.c +++ b/arch/score/mm/fault.c @@ -73,7 +73,7 @@ asmlinkage void do_page_fault(struct pt_ * If we're in an interrupt or have no user * context, we must not take the fault.. */ - if (in_atomic() || !mm || current->pagefault_disabled) + if (!mm || pagefault_disabled()) goto bad_area_nosemaphore; if (user_mode(regs)) --- a/arch/sh/mm/fault.c +++ b/arch/sh/mm/fault.c @@ -438,7 +438,7 @@ asmlinkage void __kprobes do_page_fault( * If we're in an interrupt, have no user context or are running * in an atomic region then we must not take the fault: */ - if (unlikely(in_atomic() || !mm || current->pagefault_disabled)) { + if (unlikely(!mm || pagefault_disabled())) { bad_area_nosemaphore(regs, error_code, address); return; } --- a/arch/sparc/mm/fault_32.c +++ b/arch/sparc/mm/fault_32.c @@ -199,7 +199,7 @@ asmlinkage void do_sparc_fault(struct pt * If we're in an interrupt or have no user * context, we must not take the fault.. */ - if (in_atomic() || !mm || current->pagefault_disabled) + if (!mm || pagefault_disabled()) goto no_context; perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS, 1, regs, address); --- a/arch/sparc/mm/fault_64.c +++ b/arch/sparc/mm/fault_64.c @@ -324,7 +324,7 @@ asmlinkage void __kprobes do_sparc64_fau * If we're in an interrupt or have no user * context, we must not take the fault.. */ - if (in_atomic() || !mm || current->pagefault_enabled) + if (!mm || pagefault_disabled()) goto intr_or_no_mm; perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS, 1, regs, address); --- a/arch/tile/mm/fault.c +++ b/arch/tile/mm/fault.c @@ -357,7 +357,7 @@ static int handle_page_fault(struct pt_r * If we're in an interrupt, have no user context or are running in an * atomic region then we must not take the fault. */ - if (in_atomic() || !mm || current->pagefault_disabled) { + if (!mm || pagefault_disabled()) { vma = NULL; /* happy compiler */ goto bad_area_nosemaphore; } --- a/arch/um/kernel/trap.c +++ b/arch/um/kernel/trap.c @@ -38,7 +38,7 @@ int handle_page_fault(unsigned long addr * If the fault was during atomic operation, don't take the fault, just * fail. */ - if (in_atomic() || current->pagefault_disabled) + if (pagefault_disabled()) goto out_nosemaphore; if (is_user) --- a/arch/x86/mm/fault.c +++ b/arch/x86/mm/fault.c @@ -1103,7 +1103,7 @@ static void __kprobes noinline * If we're in an interrupt, have no user context or are running * in an atomic region then we must not take the fault: */ - if (unlikely(in_atomic() || !mm || current->pagefault_disabled)) { + if (unlikely(!mm || pagefault_disabled())) { bad_area_nosemaphore(regs, error_code, address); return; } --- a/arch/xtensa/mm/fault.c +++ b/arch/xtensa/mm/fault.c @@ -57,7 +57,7 @@ void do_page_fault(struct pt_regs *regs) /* If we're in an interrupt or have no user * context, we must not take the fault.. */ - if (in_atomic() || !mm || current->pagefault_disabled) { + if (!mm || pagefault_disabled()) { bad_page_fault(regs, address, SIGSEGV); return; } --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -54,6 +54,7 @@ struct sched_param { #include #include #include +#include #include @@ -1388,7 +1389,9 @@ struct task_struct { /* mutex deadlock detection */ struct mutex_waiter *blocked_on; #endif +#ifdef CONFIG_PREEMPT_RT_FULL int pagefault_disabled; +#endif #ifdef CONFIG_TRACE_IRQFLAGS unsigned int irq_events; unsigned long hardirq_enable_ip; @@ -1622,6 +1625,17 @@ static inline void task_numa_free(struct } #endif +#ifdef CONFIG_PREEMPT_RT_FULL +static inline bool cur_pf_disabled(void) { return current->pagefault_disabled; } +#else +static inline bool cur_pf_disabled(void) { return false; } +#endif + +static inline bool pagefault_disabled(void) +{ + return in_atomic() || cur_pf_disabled(); +} + static inline struct pid *task_pid(struct task_struct *task) { return task->pids[PIDTYPE_PID].pid; --- a/kernel/fork.c +++ b/kernel/fork.c @@ -1298,7 +1298,9 @@ static struct task_struct *copy_process( p->hardirq_context = 0; p->softirq_context = 0; #endif +#ifdef CONFIG_PREEMPT_RT_FULL p->pagefault_disabled = 0; +#endif #ifdef CONFIG_LOCKDEP p->lockdep_depth = 0; /* no locks held yet */ p->curr_chain_key = 0;