Commits
Tom Zanussi committed d0bad49bb0a
tracing: Add enable_hist/disable_hist triggers Similar to enable_event/disable_event triggers, these triggers enable and disable the aggregation of events into maps rather than enabling and disabling their writing into the trace buffer. They can be used to automatically start and stop hist triggers based on a matching filter condition. If there's a paused hist trigger on system:event, the following would start it when the filter condition was hit: # echo enable_hist:system:event [ if filter] > event/trigger And the following would disable a running system:event hist trigger: # echo disable_hist:system:event [ if filter] > event/trigger See Documentation/trace/events.txt for real examples. Link: http://lkml.kernel.org/r/f812f086e52c8b7c8ad5443487375e03c96a601f.1457029949.git.tom.zanussi@linux.intel.com Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com> Tested-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Reviewed-by: Namhyung Kim <namhyung@kernel.org> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>