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| author | Steven Rostedt (Google) <rostedt@goodmis.org> | 2022-06-07 12:28:57 -0400 |
|---|---|---|
| committer | Steven Rostedt (Google) <rostedt@goodmis.org> | 2022-06-08 12:55:13 -0400 |
| commit | 689a9daf4ac598002c973f380567e6f97eddf4d2 (patch) | |
| tree | 5e83e17a30e758641803babc2cc146a29944eaed | |
| parent | f525391da6d00e300809b758193dcdebb8c9c9ed (diff) | |
| download | trace-cmd-689a9daf4ac598002c973f380567e6f97eddf4d2.tar.gz | |
trace-cmd report: Explain the '-l' option better in the man page
The '-l' option shows latency information of each event. It is not well
documented. Update the man page to show what the cryptic values mean.
Link: https://lore.kernel.org/linux-trace-devel/20220607122857.2dd8b761@gandalf.local.home
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=216069
Reported-by: Julia Lawall <julia.lawall@inria.fr>
Acked-by: Julia Lawall <julia.lawall@inria.fr>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
| -rw-r--r-- | Documentation/trace-cmd/trace-cmd-report.1.txt | 39 |
1 files changed, 32 insertions, 7 deletions
diff --git a/Documentation/trace-cmd/trace-cmd-report.1.txt b/Documentation/trace-cmd/trace-cmd-report.1.txt index 8e5c4970..71df9a8e 100644 --- a/Documentation/trace-cmd/trace-cmd-report.1.txt +++ b/Documentation/trace-cmd/trace-cmd-report.1.txt @@ -221,13 +221,38 @@ OPTIONS <idle>-0 0d.h1. 106467.859747: function: ktime_get <-- tick_check_idle ---- - The 0d.h1. denotes this information. The first character is never a '.' - and represents what CPU the trace was recorded on (CPU 0). The 'd' denotes - that interrupts were disabled. The 'h' means that this was called inside - an interrupt handler. The '1' is the preemption disabled (preempt_count) - was set to one. The two '.'s are "need_resched" flag and kernel lock - counter. If the "need_resched" flag is set, then that character would be a - 'N'. + The 0d.h1. denotes this information. + + It starts with a number. This represents the CPU number that the event occurred + on. + + The second character is one of the following: + + 'd' - Interrupts are disabled + '.' - Interrupts are enabled + 'X' - Has flags that are not yet known by trace-cmd + + The third character is the "need rescheduling" flag. + + 'N' - A schedule is set to take place + '.' - No scheduling is set + + The fourth character represents the context the event was in when it triggered + + 'h' - Hard interrupt context + 's' - Soft interrupt context + 'H' - Hard interrupt context that interrupted a soft interrupt + '.' - Normal context + + The next is a number (should be less than 10), that represents the preemption + depth (the number of times preempt_disable() is called without preempt_enable()). + '.' means preemption is enabled. + + On some systems, "migrate disable" may exist, in which case a number will be + shown for that, or '.' meaning migration is enabled. + + If lockdep in enabled on the system, then the number represents the depth of + locks that are held when the event triggered. '.' means no locks are held. *-w*:: If both the 'sched_switch' and 'sched_wakeup' events are enabled, then |