From: Tom Zanussi <tom.zanu...@linux.intel.com>
Add abbreviated documentation for handlers and actions to README.
Signed-off-by: Tom Zanussi <tom.zanu...@linux.intel.com>
---
kernel/trace/trace.c | 12 +++++++++++-
1 file changed, 11 insertions(+), 1 deletion(-)
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 911470ad9e94..1abde13a7eab 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -4698,6 +4698,7 @@ 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 When a matching event is hit, an entry is added to a hash\n"
"\t table using the key(s) and value(s) named, and the value of a\n"
@@ -4739,7 +4740,16 @@ 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
;
--
2.14.1
