diff options
| -rw-r--r-- | fs/exec.c | 1 | ||||
| -rw-r--r-- | include/linux/perf_counter.h | 16 | ||||
| -rw-r--r-- | kernel/perf_counter.c | 93 |
3 files changed, 109 insertions, 1 deletions
diff --git a/fs/exec.c b/fs/exec.c index e015c0b5a08..bf47ed0278f 100644 --- a/fs/exec.c +++ b/fs/exec.c @@ -951,6 +951,7 @@ void set_task_comm(struct task_struct *tsk, char *buf) task_lock(tsk); strlcpy(tsk->comm, buf, sizeof(tsk->comm)); task_unlock(tsk); + perf_counter_comm(tsk); } int flush_old_exec(struct linux_binprm * bprm) diff --git a/include/linux/perf_counter.h b/include/linux/perf_counter.h index 8bf764fc622..a70a55f2759 100644 --- a/include/linux/perf_counter.h +++ b/include/linux/perf_counter.h @@ -142,8 +142,9 @@ struct perf_counter_hw_event { exclude_idle : 1, /* don't count when idle */ mmap : 1, /* include mmap data */ munmap : 1, /* include munmap data */ + comm : 1, /* include comm data */ - __reserved_1 : 53; + __reserved_1 : 52; __u32 extra_config_len; __u32 wakeup_events; /* wakeup every n events */ @@ -231,6 +232,16 @@ enum perf_event_type { PERF_EVENT_MUNMAP = 2, /* + * struct { + * struct perf_event_header header; + * + * u32 pid, tid; + * char comm[]; + * }; + */ + PERF_EVENT_COMM = 3, + + /* * When header.misc & PERF_EVENT_MISC_OVERFLOW the event_type field * will be PERF_RECORD_* * @@ -545,6 +556,8 @@ extern void perf_counter_mmap(unsigned long addr, unsigned long len, 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); + #define MAX_STACK_DEPTH 255 struct perf_callchain_entry { @@ -583,6 +596,7 @@ static inline void 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) { } #endif #endif /* __KERNEL__ */ diff --git a/kernel/perf_counter.c b/kernel/perf_counter.c index bf12df6f353..2d4aebb2982 100644 --- a/kernel/perf_counter.c +++ b/kernel/perf_counter.c @@ -1917,6 +1917,99 @@ static void perf_counter_output(struct perf_counter *counter, } /* + * comm tracking + */ + +struct perf_comm_event { + struct task_struct *task; + char *comm; + int comm_size; + + struct { + struct perf_event_header header; + + u32 pid; + u32 tid; + } event; +}; + +static void perf_counter_comm_output(struct perf_counter *counter, + struct perf_comm_event *comm_event) +{ + struct perf_output_handle handle; + int size = comm_event->event.header.size; + int ret = perf_output_begin(&handle, counter, size, 0, 0); + + if (ret) + return; + + perf_output_put(&handle, comm_event->event); + perf_output_copy(&handle, comm_event->comm, + comm_event->comm_size); + perf_output_end(&handle); +} + +static int perf_counter_comm_match(struct perf_counter *counter, + struct perf_comm_event *comm_event) +{ + if (counter->hw_event.comm && + comm_event->event.header.type == PERF_EVENT_COMM) + return 1; + + return 0; +} + +static void perf_counter_comm_ctx(struct perf_counter_context *ctx, + struct perf_comm_event *comm_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_comm_match(counter, comm_event)) + perf_counter_comm_output(counter, comm_event); + } + rcu_read_unlock(); +} + +static void perf_counter_comm_event(struct perf_comm_event *comm_event) +{ + struct perf_cpu_context *cpuctx; + unsigned int size; + char *comm = comm_event->task->comm; + + size = ALIGN(strlen(comm), sizeof(u64)); + + comm_event->comm = comm; + comm_event->comm_size = size; + + comm_event->event.header.size = sizeof(comm_event->event) + size; + + cpuctx = &get_cpu_var(perf_cpu_context); + perf_counter_comm_ctx(&cpuctx->ctx, comm_event); + put_cpu_var(perf_cpu_context); + + perf_counter_comm_ctx(¤t->perf_counter_ctx, comm_event); +} + +void perf_counter_comm(struct task_struct *task) +{ + struct perf_comm_event comm_event = { + .task = task, + .event = { + .header = { .type = PERF_EVENT_COMM, }, + .pid = task->group_leader->pid, + .tid = task->pid, + }, + }; + + perf_counter_comm_event(&comm_event); +} + +/* * mmap tracking */ |