diff options
Diffstat (limited to 'kernel/trace/trace.c')
| -rw-r--r-- | kernel/trace/trace.c | 69 |
1 files changed, 44 insertions, 25 deletions
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 95f99a7abf2f..e1f3b99a2e52 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -336,7 +336,7 @@ __update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) data->rt_priority = tsk->rt_priority; /* record this tasks comm */ - tracing_record_cmdline(current); + tracing_record_cmdline(tsk); } static void @@ -499,6 +499,9 @@ __acquires(kernel_lock) else if (!type->flags->opts) type->flags->opts = dummy_tracer_opt; + if (!type->wait_pipe) + type->wait_pipe = default_wait_pipe; + #ifdef CONFIG_FTRACE_STARTUP_TEST if (type->selftest && !tracing_selftest_disabled) { @@ -1064,7 +1067,10 @@ tracing_sched_wakeup_trace(struct trace_array *tr, entry->next_prio = wakee->prio; entry->next_state = wakee->state; entry->next_cpu = task_cpu(wakee); - trace_buffer_unlock_commit(tr, event, flags, pc); + + ring_buffer_unlock_commit(tr->buffer, event); + ftrace_trace_stack(tr, flags, 6, pc); + ftrace_trace_userstack(tr, flags, pc); } void @@ -2392,6 +2398,38 @@ tracing_poll_pipe(struct file *filp, poll_table *poll_table) } } + +void default_wait_pipe(struct trace_iterator *iter) +{ + DEFINE_WAIT(wait); + + prepare_to_wait(&trace_wait, &wait, TASK_INTERRUPTIBLE); + + if (trace_empty(iter)) + schedule(); + + finish_wait(&trace_wait, &wait); +} + +/* + * This is a make-shift waitqueue. + * A tracer might use this callback on some rare cases: + * + * 1) the current tracer might hold the runqueue lock when it wakes up + * a reader, hence a deadlock (sched, function, and function graph tracers) + * 2) the function tracers, trace all functions, we don't want + * the overhead of calling wake_up and friends + * (and tracing them too) + * + * Anyway, this is really very primitive wakeup. + */ +void poll_wait_pipe(struct trace_iterator *iter) +{ + set_current_state(TASK_INTERRUPTIBLE); + /* sleep for 100 msecs, and try again. */ + schedule_timeout(HZ / 10); +} + /* Must be called with trace_types_lock mutex held. */ static int tracing_wait_pipe(struct file *filp) { @@ -2403,30 +2441,14 @@ static int tracing_wait_pipe(struct file *filp) return -EAGAIN; } - /* - * This is a make-shift waitqueue. The reason we don't use - * an actual wait queue is because: - * 1) we only ever have one waiter - * 2) the tracing, traces all functions, we don't want - * the overhead of calling wake_up and friends - * (and tracing them too) - * Anyway, this is really very primitive wakeup. - */ - set_current_state(TASK_INTERRUPTIBLE); - iter->tr->waiter = current; - mutex_unlock(&trace_types_lock); - /* sleep for 100 msecs, and try again. */ - schedule_timeout(HZ/10); + iter->trace->wait_pipe(iter); mutex_lock(&trace_types_lock); - iter->tr->waiter = NULL; - - if (signal_pending(current)) { + if (signal_pending(current)) return -EINTR; - } if (iter->trace != current_trace) return 0; @@ -2442,8 +2464,6 @@ static int tracing_wait_pipe(struct file *filp) */ if (!tracer_enabled && iter->pos) break; - - continue; } return 1; @@ -2551,8 +2571,7 @@ static struct pipe_buf_operations tracing_pipe_buf_ops = { }; static size_t -tracing_fill_pipe_page(struct page *pages, size_t rem, - struct trace_iterator *iter) +tracing_fill_pipe_page(size_t rem, struct trace_iterator *iter) { size_t count; int ret; @@ -2629,7 +2648,7 @@ static ssize_t tracing_splice_read_pipe(struct file *filp, if (!pages[i]) break; - rem = tracing_fill_pipe_page(pages[i], rem, iter); + rem = tracing_fill_pipe_page(rem, iter); /* Copy the data into the page, so we can start over. */ ret = trace_seq_to_buffer(&iter->seq, |