diff options
Diffstat (limited to 'kernel/trace/trace.c')
-rw-r--r-- | kernel/trace/trace.c | 12 |
1 files changed, 11 insertions, 1 deletions
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 559f2ad02a41..8292c7441e23 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -4754,6 +4754,7 @@ static const char readme_msg[] = "\t [:size=#entries]\n" "\t [:pause][:continue][:clear]\n" "\t [:name=histname1]\n" + "\t [:<handler>.<action>]\n" "\t [if <filter>]\n\n" "\t Note, special fields can be used as well:\n" "\t common_timestamp - to record current timestamp\n" @@ -4799,7 +4800,16 @@ static const char readme_msg[] = "\t The enable_hist and disable_hist triggers can be used to\n" "\t have one event conditionally start and stop another event's\n" "\t already-attached hist trigger. The syntax is analagous to\n" - "\t the enable_event and disable_event triggers.\n" + "\t the enable_event and disable_event triggers.\n\n" + "\t Hist trigger handlers and actions are executed whenever a\n" + "\t a histogram entry is added or updated. They take the form:\n\n" + "\t <handler>.<action>\n\n" + "\t The available handlers are:\n\n" + "\t onmatch(matching.event) - invoke on addition or update\n" + "\t onmax(var) - invoke if var exceeds current max\n\n" + "\t The available actions are:\n\n" + "\t <synthetic_event>(param list) - generate synthetic event\n" + "\t save(field,...) - save current event fields\n" #endif ; |