From 0d5c6e1c19bab82fad4837108c2902f557d62a04 Mon Sep 17 00:00:00 2001 From: Steven Rostedt Date: Thu, 1 Nov 2012 20:54:21 -0400 Subject: tracing: Use irq_work for wake ups and remove *_nowake_*() functions Have the ring buffer commit function use the irq_work infrastructure to wake up any waiters waiting on the ring buffer for new data. The irq_work was created for such a purpose, where doing the actual wake up at the time of adding data is too dangerous, as an event or function trace may be in the midst of the work queue locks and cause deadlocks. The irq_work will either delay the action to the next timer interrupt, or trigger an IPI to itself forcing an interrupt to do the work (in a safe location). With irq_work, all ring buffer commits can safely do wakeups, removing the need for the ring buffer commit "nowake" variants, which were used by events and function tracing. All commits can now safely use the normal commit, and the "nowake" variants can be removed. Cc: Peter Zijlstra Signed-off-by: Steven Rostedt --- kernel/trace/Kconfig | 1 + 1 file changed, 1 insertion(+) (limited to 'kernel/trace/Kconfig') diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig index 4cea4f41c1d9..5d89335a485f 100644 --- a/kernel/trace/Kconfig +++ b/kernel/trace/Kconfig @@ -119,6 +119,7 @@ config TRACING select BINARY_PRINTF select EVENT_TRACING select TRACE_CLOCK + select IRQ_WORK config GENERIC_TRACER bool -- cgit v1.2.3