diff options
| author | Tom Zanussi | 2019-02-13 17:42:46 -0600 |
|---|---|---|
| committer | Steven Rostedt (VMware) | 2019-02-20 13:51:07 -0500 |
| commit | a3785b7eca8fd45c7c39f2ddfcd67368af30c1b4 (patch) | |
| tree | 7090f2e113486f00c6f26da049ce0e581eceb162 /kernel/trace/trace.c | |
| parent | a35873a0993b4d38b40871f10fa4356c088c7140 (diff) | |
tracing: Add hist trigger snapshot() action
Add support for hist:handlerXXX($var).snapshot(), which will take a
snapshot of the current trace buffer whenever handlerXXX is hit.
As a first user, this also adds snapshot() action support for the
onmax() handler i.e. hist:onmax($var).snapshot().
Also, the hist trigger key printing is moved into a separate function
so the snapshot() action can print a histogram key outside the
histogram display - add and use hist_trigger_print_key() for that
purpose.
Link: http://lkml.kernel.org/r/2f1a952c0dcd8aca8702ce81269581a692396d45.1550100284.git.tom.zanussi@linux.intel.com
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Diffstat (limited to 'kernel/trace/trace.c')
| -rw-r--r-- | kernel/trace/trace.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 9f4d56f74b46..dd60c14a0fb0 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -4919,6 +4919,9 @@ static const char readme_msg[] = "\t The available actions are:\n\n" "\t <synthetic_event>(param list) - generate synthetic event\n" "\t save(field,...) - save current event fields\n" +#ifdef CONFIG_TRACER_SNAPSHOT + "\t snapshot() - snapshot the trace buffer\n" +#endif #endif ; |