diff options
| -rw-r--r-- | include/linux/perf_counter.h | 10 | ||||
| -rw-r--r-- | kernel/fork.c | 4 | ||||
| -rw-r--r-- | kernel/perf_counter.c | 131 |
3 files changed, 126 insertions, 19 deletions
diff --git a/include/linux/perf_counter.h b/include/linux/perf_counter.h index 37d5541d74c..380247bdb91 100644 --- a/include/linux/perf_counter.h +++ b/include/linux/perf_counter.h @@ -277,6 +277,14 @@ enum perf_event_type { PERF_EVENT_UNTHROTTLE = 6, /* + * struct { + * struct perf_event_header header; + * u32 pid, ppid; + * }; + */ + PERF_EVENT_FORK = 7, + + /* * When header.misc & PERF_EVENT_MISC_OVERFLOW the event_type field * will be PERF_RECORD_* * @@ -618,6 +626,7 @@ extern void perf_counter_munmap(unsigned long addr, unsigned long len, unsigned long pgoff, struct file *file); extern void perf_counter_comm(struct task_struct *tsk); +extern void perf_counter_fork(struct task_struct *tsk); extern void perf_counter_task_migration(struct task_struct *task, int cpu); @@ -673,6 +682,7 @@ perf_counter_munmap(unsigned long addr, unsigned long len, unsigned long pgoff, struct file *file) { } static inline void perf_counter_comm(struct task_struct *tsk) { } +static inline void perf_counter_fork(struct task_struct *tsk) { } static inline void perf_counter_init(void) { } static inline void perf_counter_task_migration(struct task_struct *task, int cpu) { } diff --git a/kernel/fork.c b/kernel/fork.c index b7d7a9f0bd7..f4466ca37ec 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -1412,12 +1412,12 @@ long do_fork(unsigned long clone_flags, if (clone_flags & CLONE_VFORK) { p->vfork_done = &vfork; init_completion(&vfork); - } else { + } else if (!(clone_flags & CLONE_VM)) { /* * vfork will do an exec which will call * set_task_comm() */ - perf_counter_comm(p); + perf_counter_fork(p); } audit_finish_fork(p); diff --git a/kernel/perf_counter.c b/kernel/perf_counter.c index 0bb03f15a5b..78c58623a0d 100644 --- a/kernel/perf_counter.c +++ b/kernel/perf_counter.c @@ -40,9 +40,9 @@ static int perf_reserved_percpu __read_mostly; static int perf_overcommit __read_mostly = 1; static atomic_t nr_counters __read_mostly; -static atomic_t nr_mmap_tracking __read_mostly; -static atomic_t nr_munmap_tracking __read_mostly; -static atomic_t nr_comm_tracking __read_mostly; +static atomic_t nr_mmap_counters __read_mostly; +static atomic_t nr_munmap_counters __read_mostly; +static atomic_t nr_comm_counters __read_mostly; int sysctl_perf_counter_priv __read_mostly; /* do we need to be privileged */ int sysctl_perf_counter_mlock __read_mostly = 512; /* 'free' kb per user */ @@ -1447,11 +1447,11 @@ static void free_counter(struct perf_counter *counter) atomic_dec(&nr_counters); if (counter->attr.mmap) - atomic_dec(&nr_mmap_tracking); + atomic_dec(&nr_mmap_counters); if (counter->attr.munmap) - atomic_dec(&nr_munmap_tracking); + atomic_dec(&nr_munmap_counters); if (counter->attr.comm) - atomic_dec(&nr_comm_tracking); + atomic_dec(&nr_comm_counters); if (counter->destroy) counter->destroy(counter); @@ -2476,6 +2476,105 @@ static void perf_counter_output(struct perf_counter *counter, } /* + * fork tracking + */ + +struct perf_fork_event { + struct task_struct *task; + + struct { + struct perf_event_header header; + + u32 pid; + u32 ppid; + } event; +}; + +static void perf_counter_fork_output(struct perf_counter *counter, + struct perf_fork_event *fork_event) +{ + struct perf_output_handle handle; + int size = fork_event->event.header.size; + struct task_struct *task = fork_event->task; + int ret = perf_output_begin(&handle, counter, size, 0, 0); + + if (ret) + return; + + fork_event->event.pid = perf_counter_pid(counter, task); + fork_event->event.ppid = perf_counter_pid(counter, task->real_parent); + + perf_output_put(&handle, fork_event->event); + perf_output_end(&handle); +} + +static int perf_counter_fork_match(struct perf_counter *counter) +{ + if (counter->attr.comm || counter->attr.mmap || counter->attr.munmap) + return 1; + + return 0; +} + +static void perf_counter_fork_ctx(struct perf_counter_context *ctx, + struct perf_fork_event *fork_event) +{ + struct perf_counter *counter; + + if (system_state != SYSTEM_RUNNING || list_empty(&ctx->event_list)) + return; + + rcu_read_lock(); + list_for_each_entry_rcu(counter, &ctx->event_list, event_entry) { + if (perf_counter_fork_match(counter)) + perf_counter_fork_output(counter, fork_event); + } + rcu_read_unlock(); +} + +static void perf_counter_fork_event(struct perf_fork_event *fork_event) +{ + struct perf_cpu_context *cpuctx; + struct perf_counter_context *ctx; + + cpuctx = &get_cpu_var(perf_cpu_context); + perf_counter_fork_ctx(&cpuctx->ctx, fork_event); + put_cpu_var(perf_cpu_context); + + rcu_read_lock(); + /* + * doesn't really matter which of the child contexts the + * events ends up in. + */ + ctx = rcu_dereference(current->perf_counter_ctxp); + if (ctx) + perf_counter_fork_ctx(ctx, fork_event); + rcu_read_unlock(); +} + +void perf_counter_fork(struct task_struct *task) +{ + struct perf_fork_event fork_event; + + if (!atomic_read(&nr_comm_counters) && + !atomic_read(&nr_mmap_counters) && + !atomic_read(&nr_munmap_counters)) + return; + + fork_event = (struct perf_fork_event){ + .task = task, + .event = { + .header = { + .type = PERF_EVENT_FORK, + .size = sizeof(fork_event.event), + }, + }, + }; + + perf_counter_fork_event(&fork_event); +} + +/* * comm tracking */ @@ -2511,11 +2610,9 @@ static void perf_counter_comm_output(struct perf_counter *counter, perf_output_end(&handle); } -static int perf_counter_comm_match(struct perf_counter *counter, - struct perf_comm_event *comm_event) +static int perf_counter_comm_match(struct perf_counter *counter) { - if (counter->attr.comm && - comm_event->event.header.type == PERF_EVENT_COMM) + if (counter->attr.comm) return 1; return 0; @@ -2531,7 +2628,7 @@ static void perf_counter_comm_ctx(struct perf_counter_context *ctx, rcu_read_lock(); list_for_each_entry_rcu(counter, &ctx->event_list, event_entry) { - if (perf_counter_comm_match(counter, comm_event)) + if (perf_counter_comm_match(counter)) perf_counter_comm_output(counter, comm_event); } rcu_read_unlock(); @@ -2570,7 +2667,7 @@ void perf_counter_comm(struct task_struct *task) { struct perf_comm_event comm_event; - if (!atomic_read(&nr_comm_tracking)) + if (!atomic_read(&nr_comm_counters)) return; comm_event = (struct perf_comm_event){ @@ -2708,7 +2805,7 @@ void perf_counter_mmap(unsigned long addr, unsigned long len, { struct perf_mmap_event mmap_event; - if (!atomic_read(&nr_mmap_tracking)) + if (!atomic_read(&nr_mmap_counters)) return; mmap_event = (struct perf_mmap_event){ @@ -2729,7 +2826,7 @@ void perf_counter_munmap(unsigned long addr, unsigned long len, { struct perf_mmap_event mmap_event; - if (!atomic_read(&nr_munmap_tracking)) + if (!atomic_read(&nr_munmap_counters)) return; mmap_event = (struct perf_mmap_event){ @@ -3427,11 +3524,11 @@ done: atomic_inc(&nr_counters); if (counter->attr.mmap) - atomic_inc(&nr_mmap_tracking); + atomic_inc(&nr_mmap_counters); if (counter->attr.munmap) - atomic_inc(&nr_munmap_tracking); + atomic_inc(&nr_munmap_counters); if (counter->attr.comm) - atomic_inc(&nr_comm_tracking); + atomic_inc(&nr_comm_counters); return counter; } |