On Mon, 23 Mar 2009, Frederic Weisbecker wrote: > tracing/events: don't use wake up for events > > Impact: fix hard-lockup with sched switch events > > Some ftrace events, such as sched wakeup, can be traced > while the runqueue lock is hold. Since they are using > trace_current_buffer_unlock_commit(), they call wake_up() > which can try to grab the runqueue lock too, resulting in > a deadlock. > > Now for all event, we call a new helper: > trace_nowake_buffer_unlock_commit() which do pretty the same than Ug, that's an ugly name. It should at least be: trace_buffer_unlock_commit_nowake to be more in line with kernel conventions. That is where the derivitive has the same name as the original, like preempt_enable_noresched. -- Steve > trace_current_buffer_unlock_commit() except than it doesn't call > trace_wake_up(). > > Reported-by: Ingo Molnar <mingo@xxxxxxx> > Signed-off-by: Frederic Weisbecker <fweisbec@xxxxxxxxx> > Cc: Steven Rostedt <rostedt@xxxxxxxxxxx> > LKML-Reference: <1237759847-21025-4-git-send-email-fweisbec@xxxxxxxxx> > Signed-off-by: Ingo Molnar <mingo@xxxxxxx> > > -- To unsubscribe from this list: send the line "unsubscribe linux-tip-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
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