From 7dd1fcc258b65da718f01e4684a7b9244501a9fb Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Fri, 13 Mar 2009 12:21:33 +0100 Subject: [PATCH] perf_counter: provide pagefault software events We use the generic software counter infrastructure to provide page fault events. Signed-off-by: Peter Zijlstra Signed-off-by: Ingo Molnar --- arch/powerpc/mm/fault.c | 3 +++ arch/x86/mm/fault.c | 3 +++ kernel/perf_counter.c | 53 +++-------------------------------------- 3 files changed, 9 insertions(+), 50 deletions(-) diff --git a/arch/powerpc/mm/fault.c b/arch/powerpc/mm/fault.c index 76993941cac9..eda5b0ca4af2 100644 --- a/arch/powerpc/mm/fault.c +++ b/arch/powerpc/mm/fault.c @@ -29,6 +29,7 @@ #include #include #include +#include #include #include @@ -170,6 +171,8 @@ int __kprobes do_page_fault(struct pt_regs *regs, unsigned long address, die("Weird page fault", regs, SIGSEGV); } + perf_swcounter_event(PERF_COUNT_PAGE_FAULTS, 1, 0, regs); + /* When running in the kernel we expect faults to occur only to * addresses in user space. All other faults represent errors in the * kernel and should generate an OOPS. Unfortunately, in the case of an diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c index a03b7279efa0..c8725752b6cd 100644 --- a/arch/x86/mm/fault.c +++ b/arch/x86/mm/fault.c @@ -27,6 +27,7 @@ #include #include #include +#include #include @@ -1044,6 +1045,8 @@ do_page_fault(struct pt_regs *regs, unsigned long error_code) if (unlikely(error_code & PF_RSVD)) pgtable_bad(regs, error_code, address); + perf_swcounter_event(PERF_COUNT_PAGE_FAULTS, 1, 0, regs); + /* * If we're in an interrupt, have no user context or are running * in an atomic region then we must not take the fault: diff --git a/kernel/perf_counter.c b/kernel/perf_counter.c index eeb1b46cf707..1773c5d7427d 100644 --- a/kernel/perf_counter.c +++ b/kernel/perf_counter.c @@ -1607,57 +1607,10 @@ static const struct hw_perf_counter_ops perf_ops_task_clock = { * Software counter: page faults */ -#ifdef CONFIG_VM_EVENT_COUNTERS -#define cpu_page_faults() __get_cpu_var(vm_event_states).event[PGFAULT] -#else -#define cpu_page_faults() 0 -#endif - -static u64 get_page_faults(struct perf_counter *counter) -{ - struct task_struct *curr = counter->ctx->task; - - if (curr) - return curr->maj_flt + curr->min_flt; - return cpu_page_faults(); -} - -static void page_faults_perf_counter_update(struct perf_counter *counter) -{ - u64 prev, now; - s64 delta; - - prev = atomic64_read(&counter->hw.prev_count); - now = get_page_faults(counter); - - atomic64_set(&counter->hw.prev_count, now); - - delta = now - prev; - - atomic64_add(delta, &counter->count); -} - -static void page_faults_perf_counter_read(struct perf_counter *counter) -{ - page_faults_perf_counter_update(counter); -} - -static int page_faults_perf_counter_enable(struct perf_counter *counter) -{ - if (counter->prev_state <= PERF_COUNTER_STATE_OFF) - atomic64_set(&counter->hw.prev_count, get_page_faults(counter)); - return 0; -} - -static void page_faults_perf_counter_disable(struct perf_counter *counter) -{ - page_faults_perf_counter_update(counter); -} - static const struct hw_perf_counter_ops perf_ops_page_faults = { - .enable = page_faults_perf_counter_enable, - .disable = page_faults_perf_counter_disable, - .read = page_faults_perf_counter_read, + .enable = perf_swcounter_enable, + .disable = perf_swcounter_disable, + .read = perf_swcounter_read, }; /* -- 2.34.1