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sched/debug: Fix task state recording/printout

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commit 3f5fe9fef5b2da06b6319fab8123056da5217c3f upstream.

The recent conversion of the task state recording to use task_state_index()
broke the sched_switch tracepoint task state output.

task_state_index() returns surprisingly an index (0-7) which is then
printed with __print_flags() applying bitmasks. Not really working and
resulting in weird states like 'prev_state=t' instead of 'prev_state=I'.

Use TASK_REPORT_MAX instead of TASK_STATE_MAX to report preemption. Build a
bitmask from the return value of task_state_index() and store it in
entry->prev_state, which makes __print_flags() work as expected.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: stable@vger.kernel.org
Fixes: efb40f588b43 ("sched/tracing: Fix trace_sched_switch task-state printing")
Link: http://lkml.kernel.org/r/alpine.DEB.2.20.1711221304180.1751@nanos
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Thomas Gleixner 2017-11-22 13:05:48 +01:00 committed by Greg Kroah-Hartman
parent e5f4bae2e3
commit 13f12749af
1 changed files with 3 additions and 3 deletions
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6
include/trace/events/sched.h
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@ -116,9 +116,9 @@ static inline long __trace_sched_switch_state(bool preempt, struct task_struct *
* RUNNING (we will not have dequeued if state != RUNNING).
*/
if (preempt)
return TASK_STATE_MAX;
return TASK_REPORT_MAX;
return __get_task_state(p);
return 1 << __get_task_state(p);
}
#endif /* CREATE_TRACE_POINTS */
@ -164,7 +164,7 @@ TRACE_EVENT(sched_switch,
{ 0x40, "P" }, { 0x80, "I" }) :
"R",
__entry->prev_state & TASK_STATE_MAX ? "+" : "",
__entry->prev_state & TASK_REPORT_MAX ? "+" : "",
__entry->next_comm, __entry->next_pid, __entry->next_prio)
);