diff options
| author | Tom Zanussi <tom.zanussi@linux.intel.com> | 2018-01-15 20:51:48 -0600 |
|---|---|---|
| committer | Steven Rostedt (VMware) <rostedt@goodmis.org> | 2018-03-10 16:05:54 -0500 |
| commit | 860f9f6b02e9e846c4cfb3505efed331a910d0b7 (patch) | |
| tree | 2fc04be64e2ba47c05d7ce356bf0652012b43437 /kernel/trace/trace.c | |
| parent | b559d003a226911979ceb8469db4c9b621c3bc09 (diff) | |
tracing: Add usecs modifier for hist trigger timestamps
Appending .usecs onto a common_timestamp field will cause the
timestamp value to be in microseconds instead of the default
nanoseconds. A typical latency histogram using usecs would look like
this:
# echo 'hist:keys=pid,prio:ts0=common_timestamp.usecs ...
# echo 'hist:keys=next_pid:wakeup_lat=common_timestamp.usecs-$ts0 ...
This also adds an external trace_clock_in_ns() to trace.c for the
timestamp conversion.
Link: http://lkml.kernel.org/r/4e813705a170b3e13e97dc3135047362fb1a39f3.1516069914.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 | 13 |
1 files changed, 11 insertions, 2 deletions
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 988d94a05e81..82cc8891fda6 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -1168,6 +1168,14 @@ static struct { ARCH_TRACE_CLOCKS }; +bool trace_clock_in_ns(struct trace_array *tr) +{ + if (trace_clocks[tr->clock_id].in_ns) + return true; + + return false; +} + /* * trace_parser_get_init - gets the buffer for trace parser */ @@ -4694,8 +4702,9 @@ static const char readme_msg[] = "\t .sym display an address as a symbol\n" "\t .sym-offset display an address as a symbol and offset\n" "\t .execname display a common_pid as a program name\n" - "\t .syscall display a syscall id as a syscall name\n\n" - "\t .log2 display log2 value rather than raw number\n\n" + "\t .syscall display a syscall id as a syscall name\n" + "\t .log2 display log2 value rather than raw number\n" + "\t .usecs display a common_timestamp in microseconds\n\n" "\t The 'pause' parameter can be used to pause an existing hist\n" "\t trigger or to start a hist trigger but not log any events\n" "\t until told to do so. 'continue' can be used to start or\n" |