tracepoint: add generic tracepoint definitions for IPI tracing
authorNicolas Pitre <nicolas.pitre@linaro.org>
Fri, 25 Jul 2014 20:05:30 +0000 (16:05 -0400)
committerSteven Rostedt <rostedt@goodmis.org>
Fri, 8 Aug 2014 00:40:40 +0000 (20:40 -0400)
commitf6d9804d145b9c42dbbabefdda208a6a492b2236
tree6a03d7b66cdbc5d9227a3e2c9d831b3ba99896d7
parent3c49b52b155d0f723792377e1a4480a0e7ca0ba2
tracepoint: add generic tracepoint definitions for IPI tracing

The Inter Processor Interrupt is used to make another processor do a
specific action such as rescheduling tasks, signal a timer event or
execute something in another CPU's context. IRQs are already traceable
but IPIs were not. Tracing them is useful for monitoring IPI latency,
or to verify when they are the source of CPU wake-ups with power
management implications.

Three trace hooks are defined: ipi_raise, ipi_entry and ipi_exit. To make
them portable, a string is used to identify them and correlate related
events. Additionally, ipi_raise records a bitmask representing targeted
CPUs.

Link: http://lkml.kernel.org/p/1406318733-26754-3-git-send-email-nicolas.pitre@linaro.org
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
include/trace/events/ipi.h [new file with mode: 0644]