diff options
| -rw-r--r-- | kernel/perf_counter.c | 32 |
1 files changed, 15 insertions, 17 deletions
diff --git a/kernel/perf_counter.c b/kernel/perf_counter.c index 57840a94b16..59a926d04ba 100644 --- a/kernel/perf_counter.c +++ b/kernel/perf_counter.c @@ -115,6 +115,7 @@ list_add_counter(struct perf_counter *counter, struct perf_counter_context *ctx) } list_add_rcu(&counter->event_entry, &ctx->event_list); + ctx->nr_counters++; } static void @@ -122,6 +123,8 @@ list_del_counter(struct perf_counter *counter, struct perf_counter_context *ctx) { struct perf_counter *sibling, *tmp; + ctx->nr_counters--; + list_del_init(&counter->list_entry); list_del_rcu(&counter->event_entry); @@ -209,7 +212,6 @@ static void __perf_counter_remove_from_context(void *info) counter_sched_out(counter, cpuctx, ctx); counter->task = NULL; - ctx->nr_counters--; /* * Protect the list operation against NMI by disabling the @@ -276,7 +278,6 @@ retry: * succeed. */ if (!list_empty(&counter->list_entry)) { - ctx->nr_counters--; list_del_counter(counter, ctx); counter->task = NULL; } @@ -544,7 +545,6 @@ static void add_counter_to_ctx(struct perf_counter *counter, struct perf_counter_context *ctx) { list_add_counter(counter, ctx); - ctx->nr_counters++; counter->prev_state = PERF_COUNTER_STATE_OFF; counter->tstamp_enabled = ctx->time; counter->tstamp_running = ctx->time; @@ -3206,9 +3206,8 @@ static int inherit_group(struct perf_counter *parent_counter, static void sync_child_counter(struct perf_counter *child_counter, struct perf_counter *parent_counter) { - u64 parent_val, child_val; + u64 child_val; - parent_val = atomic64_read(&parent_counter->count); child_val = atomic64_read(&child_counter->count); /* @@ -3240,7 +3239,6 @@ __perf_counter_exit_task(struct task_struct *child, struct perf_counter_context *child_ctx) { struct perf_counter *parent_counter; - struct perf_counter *sub, *tmp; /* * If we do not self-reap then we have to wait for the @@ -3252,8 +3250,8 @@ __perf_counter_exit_task(struct task_struct *child, */ if (child != current) { wait_task_inactive(child, 0); - list_del_init(&child_counter->list_entry); update_counter_times(child_counter); + list_del_counter(child_counter, child_ctx); } else { struct perf_cpu_context *cpuctx; unsigned long flags; @@ -3272,9 +3270,7 @@ __perf_counter_exit_task(struct task_struct *child, group_sched_out(child_counter, cpuctx, child_ctx); update_counter_times(child_counter); - list_del_init(&child_counter->list_entry); - - child_ctx->nr_counters--; + list_del_counter(child_counter, child_ctx); perf_enable(); local_irq_restore(flags); @@ -3288,13 +3284,6 @@ __perf_counter_exit_task(struct task_struct *child, */ if (parent_counter) { sync_child_counter(child_counter, parent_counter); - list_for_each_entry_safe(sub, tmp, &child_counter->sibling_list, - list_entry) { - if (sub->parent) { - sync_child_counter(sub, sub->parent); - free_counter(sub); - } - } free_counter(child_counter); } } @@ -3315,9 +3304,18 @@ void perf_counter_exit_task(struct task_struct *child) if (likely(!child_ctx->nr_counters)) return; +again: list_for_each_entry_safe(child_counter, tmp, &child_ctx->counter_list, list_entry) __perf_counter_exit_task(child, child_counter, child_ctx); + + /* + * If the last counter was a group counter, it will have appended all + * its siblings to the list, but we obtained 'tmp' before that which + * will still point to the list head terminating the iteration. + */ + if (!list_empty(&child_ctx->counter_list)) + goto again; } /* |