diff options
| author | Ingo Molnar <mingo@elte.hu> | 2008-12-19 10:20:42 +0100 |
|---|---|---|
| committer | Ingo Molnar <mingo@elte.hu> | 2008-12-23 12:45:16 +0100 |
| commit | eef6cbf5844c620d9db9be99e4908cdf92492fb9 (patch) | |
| tree | a4601e8d8ce64ca0f23f59b889360d578f663f5b | |
| parent | perfcounters: fix task clock counter (diff) | |
| download | linux-eef6cbf5844c620d9db9be99e4908cdf92492fb9.tar.xz linux-eef6cbf5844c620d9db9be99e4908cdf92492fb9.zip | |
perfcounters: pull inherited counters
Change counter inheritance from a 'push' to a 'pull' model: instead of
child tasks pushing their final counts to the parent, reuse the wait4
infrastructure to pull counters as child tasks are exit-processed,
much like how cutime/cstime is collected.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
| -rw-r--r-- | include/linux/init_task.h | 9 | ||||
| -rw-r--r-- | kernel/exit.c | 21 |
2 files changed, 18 insertions, 12 deletions
diff --git a/include/linux/init_task.h b/include/linux/init_task.h index 23fd8909b9e5..54fa2fa2c8e4 100644 --- a/include/linux/init_task.h +++ b/include/linux/init_task.h @@ -113,6 +113,14 @@ extern struct group_info init_groups; # define CAP_INIT_BSET CAP_INIT_EFF_SET #endif +#ifdef CONFIG_PERF_COUNTERS +# define INIT_PERF_COUNTERS(tsk) \ + .perf_counter_ctx.counter_list = \ + LIST_HEAD_INIT(tsk.perf_counter_ctx.counter_list), +#else +# define INIT_PERF_COUNTERS(tsk) +#endif + /* * INIT_TASK is used to set up the first task table, touch at * your own risk!. Base=0, limit=0x1fffff (=2MB) @@ -180,6 +188,7 @@ extern struct group_info init_groups; INIT_IDS \ INIT_TRACE_IRQFLAGS \ INIT_LOCKDEP \ + INIT_PERF_COUNTERS(tsk) \ } diff --git a/kernel/exit.c b/kernel/exit.c index 244edfd96865..101b7eeff44c 100644 --- a/kernel/exit.c +++ b/kernel/exit.c @@ -153,6 +153,9 @@ static void delayed_put_task_struct(struct rcu_head *rhp) { struct task_struct *tsk = container_of(rhp, struct task_struct, rcu); +#ifdef CONFIG_PERF_COUNTERS + WARN_ON_ONCE(!list_empty(&tsk->perf_counter_ctx.counter_list)); +#endif trace_sched_process_free(tsk); put_task_struct(tsk); } @@ -922,12 +925,6 @@ static void exit_notify(struct task_struct *tsk, int group_dead) forget_original_parent(tsk); exit_task_namespaces(tsk); - /* - * Flush inherited counters to the parent - before the parent - * gets woken up by child-exit notifications. - */ - perf_counter_exit_task(tsk); - write_lock_irq(&tasklist_lock); if (group_dead) kill_orphaned_pgrp(tsk->group_leader, NULL); @@ -1122,12 +1119,6 @@ NORET_TYPE void do_exit(long code) if (tsk->splice_pipe) __free_pipe_info(tsk->splice_pipe); - /* - * These must happen late, after the PID is not - * hashed anymore, but still at a point that may sleep: - */ - perf_counter_exit_task(tsk); - preempt_disable(); /* causes final put_task_struct in finish_task_switch(). */ tsk->state = TASK_DEAD; @@ -1371,6 +1362,12 @@ static int wait_task_zombie(struct task_struct *p, int options, */ read_unlock(&tasklist_lock); + /* + * Flush inherited counters to the parent - before the parent + * gets woken up by child-exit notifications. + */ + perf_counter_exit_task(p); + retval = ru ? getrusage(p, RUSAGE_BOTH, ru) : 0; status = (p->signal->flags & SIGNAL_GROUP_EXIT) ? p->signal->group_exit_code : p->exit_code; |