tracing/boot: Add per-event histogram action options
Add a hist-trigger action syntax support to boot-time tracing.
Currently, boot-time tracing supports per-event actions as option
strings. However, for the histogram action, it has a special syntax
and usually needs a long action definition.
To make it readable and fit to the bootconfig syntax, this introduces
a new options for histogram.
Here are the histogram action options for boot-time tracing.
ftrace.[instance.INSTANCE.]event.GROUP.EVENT.hist {
keys = <KEY>[,...]
values = <VAL>[,...]
sort = <SORT-KEY>[,...]
size = <ENTRIES>
name = <HISTNAME>
var { <VAR> = <EXPR> ... }
pause|continue|clear
onmax|onchange { var = <VAR>; <ACTION> [= <PARAM>] }
onmatch { event = <EVENT>; <ACTION> [= <PARAM>] }
filter = <FILTER>
}
Where <ACTION> is one of below;
trace = <EVENT>, <ARG1>[, ...]
save = <ARG1>[, ...]
snapshot
Link: https://lkml.kernel.org/r/162856124106.203126.10501871028479029087.stgit@devnote2
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
1 file changed