From e077df4f439681e43f0db8255b2d215b342ebdc6 Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Thu, 19 Mar 2009 20:26:17 +0100 Subject: [PATCH] perf_counter: hook up the tracepoint events Impact: new perfcounters feature Enable usage of tracepoints as perf counter events. tracepoint event ids can be found in /debug/tracing/event/*/*/id and (for now) are represented as -65536+id in the type field. Signed-off-by: Peter Zijlstra Cc: Paul Mackerras Cc: Steven Rostedt Orig-LKML-Reference: <20090319194233.744044174@chello.nl> Signed-off-by: Ingo Molnar --- include/linux/perf_counter.h | 3 +++ init/Kconfig | 5 +++++ kernel/perf_counter.c | 43 ++++++++++++++++++++++++++++++++++++ 3 files changed, 51 insertions(+) diff --git a/include/linux/perf_counter.h b/include/linux/perf_counter.h index 08c11a6afebc..065984c1ff57 100644 --- a/include/linux/perf_counter.h +++ b/include/linux/perf_counter.h @@ -53,6 +53,8 @@ enum hw_event_types { PERF_COUNT_PAGE_FAULTS_MAJ = -7, PERF_SW_EVENTS_MIN = -8, + + PERF_TP_EVENTS_MIN = -65536 }; /* @@ -222,6 +224,7 @@ struct perf_counter { struct perf_data *usrdata; struct perf_data data[2]; + void (*destroy)(struct perf_counter *); struct rcu_head rcu_head; #endif }; diff --git a/init/Kconfig b/init/Kconfig index 38a2ecd47c37..4f647142f2e6 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -947,6 +947,11 @@ config PERF_COUNTERS Say Y if unsure. +config EVENT_PROFILE + bool "Tracepoint profile sources" + depends on PERF_COUNTERS && EVENT_TRACER + default y + endmenu config VM_EVENT_COUNTERS diff --git a/kernel/perf_counter.c b/kernel/perf_counter.c index 97f891ffeb40..0bbe3e45ba0d 100644 --- a/kernel/perf_counter.c +++ b/kernel/perf_counter.c @@ -1152,6 +1152,9 @@ static void free_counter_rcu(struct rcu_head *head) static void free_counter(struct perf_counter *counter) { + if (counter->destroy) + counter->destroy(counter); + call_rcu(&counter->rcu_head, free_counter_rcu); } @@ -1727,6 +1730,45 @@ static const struct hw_perf_counter_ops perf_ops_cpu_migrations = { .read = cpu_migrations_perf_counter_read, }; +#ifdef CONFIG_EVENT_PROFILE +void perf_tpcounter_event(int event_id) +{ + perf_swcounter_event(PERF_TP_EVENTS_MIN + event_id, 1, 1, + task_pt_regs(current)); +} + +extern int ftrace_profile_enable(int); +extern void ftrace_profile_disable(int); + +static void tp_perf_counter_destroy(struct perf_counter *counter) +{ + int event_id = counter->hw_event.type - PERF_TP_EVENTS_MIN; + + ftrace_profile_disable(event_id); +} + +static const struct hw_perf_counter_ops * +tp_perf_counter_init(struct perf_counter *counter) +{ + int event_id = counter->hw_event.type - PERF_TP_EVENTS_MIN; + int ret; + + ret = ftrace_profile_enable(event_id); + if (ret) + return NULL; + + counter->destroy = tp_perf_counter_destroy; + + return &perf_ops_generic; +} +#else +static const struct hw_perf_counter_ops * +tp_perf_counter_init(struct perf_counter *counter) +{ + return NULL; +} +#endif + static const struct hw_perf_counter_ops * sw_perf_counter_init(struct perf_counter *counter) { @@ -1772,6 +1814,7 @@ sw_perf_counter_init(struct perf_counter *counter) hw_ops = &perf_ops_cpu_migrations; break; default: + hw_ops = tp_perf_counter_init(counter); break; } -- 2.20.1