From: Jiri Olsa Date: Wed, 15 Feb 2012 14:51:52 +0000 (+0100) Subject: ftrace, perf: Add support to use function tracepoint in perf X-Git-Tag: v3.4-rc1~192^2~10^2~2 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=ced39002f5ea736b716ae233fb68b26d59783912;p=pandora-kernel.git ftrace, perf: Add support to use function tracepoint in perf Adding perf registration support for the ftrace function event, so it is now possible to register it via perf interface. The perf_event struct statically contains ftrace_ops as a handle for function tracer. The function tracer is registered/unregistered in open/close actions. To be efficient, we enable/disable ftrace_ops each time the traced process is scheduled in/out (via TRACE_REG_PERF_(ADD|DELL) handlers). This way tracing is enabled only when the process is running. Intentionally using this way instead of the event's hw state PERF_HES_STOPPED, which would not disable the ftrace_ops. It is now possible to use function trace within perf commands like: perf record -e ftrace:function ls perf stat -e ftrace:function ls Allowed only for root. Link: http://lkml.kernel.org/r/1329317514-8131-6-git-send-email-jolsa@redhat.com Acked-by: Frederic Weisbecker Signed-off-by: Jiri Olsa Signed-off-by: Steven Rostedt --- Reading git-diff-tree failed