diff options
| -rw-r--r-- | include/linux/perf_counter.h | 3 | ||||
| -rw-r--r-- | kernel/perf_counter.c | 50 | ||||
| -rw-r--r-- | tools/perf/builtin-stat.c | 6 |
3 files changed, 55 insertions, 4 deletions
diff --git a/include/linux/perf_counter.h b/include/linux/perf_counter.h index 3078e23c91eb..5e970c7d3fd5 100644 --- a/include/linux/perf_counter.h +++ b/include/linux/perf_counter.h @@ -179,8 +179,9 @@ struct perf_counter_attr { comm : 1, /* include comm data */ freq : 1, /* use freq, not period */ inherit_stat : 1, /* per task counts */ + enable_on_exec : 1, /* next exec enables */ - __reserved_1 : 52; + __reserved_1 : 51; __u32 wakeup_events; /* wakeup every n events */ __u32 __reserved_2; diff --git a/kernel/perf_counter.c b/kernel/perf_counter.c index 66ab1e9d1294..d55a50da2347 100644 --- a/kernel/perf_counter.c +++ b/kernel/perf_counter.c @@ -1429,6 +1429,53 @@ void perf_counter_task_tick(struct task_struct *curr, int cpu) } /* + * Enable all of a task's counters that have been marked enable-on-exec. + * This expects task == current. + */ +static void perf_counter_enable_on_exec(struct task_struct *task) +{ + struct perf_counter_context *ctx; + struct perf_counter *counter; + unsigned long flags; + int enabled = 0; + + local_irq_save(flags); + ctx = task->perf_counter_ctxp; + if (!ctx || !ctx->nr_counters) + goto out; + + __perf_counter_task_sched_out(ctx); + + spin_lock(&ctx->lock); + + list_for_each_entry(counter, &ctx->counter_list, list_entry) { + if (!counter->attr.enable_on_exec) + continue; + counter->attr.enable_on_exec = 0; + if (counter->state >= PERF_COUNTER_STATE_INACTIVE) + continue; + counter->state = PERF_COUNTER_STATE_INACTIVE; + counter->tstamp_enabled = + ctx->time - counter->total_time_enabled; + enabled = 1; + } + + /* + * Unclone this context if we enabled any counter. + */ + if (enabled && ctx->parent_ctx) { + put_ctx(ctx->parent_ctx); + ctx->parent_ctx = NULL; + } + + spin_unlock(&ctx->lock); + + perf_counter_task_sched_in(task, smp_processor_id()); + out: + local_irq_restore(flags); +} + +/* * Cross CPU call to read the hardware counter */ static void __perf_counter_read(void *info) @@ -2949,6 +2996,9 @@ void perf_counter_comm(struct task_struct *task) { struct perf_comm_event comm_event; + if (task->perf_counter_ctxp) + perf_counter_enable_on_exec(task); + if (!atomic_read(&nr_comm_counters)) return; diff --git a/tools/perf/builtin-stat.c b/tools/perf/builtin-stat.c index 201ef2367dcb..2e03524a1de0 100644 --- a/tools/perf/builtin-stat.c +++ b/tools/perf/builtin-stat.c @@ -116,8 +116,9 @@ static void create_perf_stat_counter(int counter, int pid) fd[cpu][counter], strerror(errno)); } } else { - attr->inherit = inherit; - attr->disabled = 1; + attr->inherit = inherit; + attr->disabled = 1; + attr->enable_on_exec = 1; fd[0][counter] = sys_perf_counter_open(attr, pid, -1, -1, 0); if (fd[0][counter] < 0 && verbose) @@ -262,7 +263,6 @@ static int run_perf_stat(int argc, const char **argv) * Enable counters and exec the command: */ t0 = rdclock(); - prctl(PR_TASK_PERF_COUNTERS_ENABLE); close(go_pipe[1]); wait(&status); |