From: "Steven Rostedt (Google)" <rostedt@xxxxxxxxxxx>
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.
Reported-by: Julia Lawall <julia.lawall@xxxxxxxx>
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=216069
Signed-off-by: Steven Rostedt (Google) <rostedt@xxxxxxxxxxx>
---
.../trace-cmd/trace-cmd-report.1.txt | 39 +++++++++++++++----
1 file 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 df60dd87d979..ccf635fb664b 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 forth 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
--
2.35.1
|