Re: [tip:sched/core] sched, tracing: Fix trace_sched_pi_setprio() for deboosting

[Sebastian Andrzej Siewior]

On 2018-05-25 02:47:20 [-0700], tip-bot for Sebastian Andrzej Siewior wrote:
> Commit-ID:  4ff648decf4712d39f184fc2df3163f43975575a
> Gitweb: 
> https://git.kernel.org/tip/4ff648decf4712d39f184fc2df3163f43975575a
> Author: Sebastian Andrzej Siewior 
> AuthorDate: Thu, 24 May 2018 15:26:48 +0200
> Committer:  Ingo Molnar 
> CommitDate: Fri, 25 May 2018 08:04:01 +0200
> 
> sched, tracing: Fix trace_sched_pi_setprio() for deboosting
> 
> Since the following commit:
> 
>   b91473ff6e97 ("sched,tracing: Update trace_sched_pi_setprio()")
> 
> the sched_pi_setprio trace point shows the "newprio" during a deboost:
> 
>   |futex sched_pi_setprio: comm=futex_requeue_p pid"34 oldprio˜ newprio=3D98
>   |futex sched_switch: prev_comm=futex_requeue_p prev_pid"34 prev_prio=120

pid=2234 got turned into pid"34 the same for other fields.

Sebastian

Re: [tip:sched/core] sched, tracing: Fix trace_sched_pi_setprio() for deboosting

[Sebastian Andrzej Siewior]

On 2018-05-25 02:47:20 [-0700], tip-bot for Sebastian Andrzej Siewior wrote:
> Commit-ID:  4ff648decf4712d39f184fc2df3163f43975575a
> Gitweb: 
> https://git.kernel.org/tip/4ff648decf4712d39f184fc2df3163f43975575a
> Author: Sebastian Andrzej Siewior 
> AuthorDate: Thu, 24 May 2018 15:26:48 +0200
> Committer:  Ingo Molnar 
> CommitDate: Fri, 25 May 2018 08:04:01 +0200
> 
> sched, tracing: Fix trace_sched_pi_setprio() for deboosting
> 
> Since the following commit:
> 
>   b91473ff6e97 ("sched,tracing: Update trace_sched_pi_setprio()")
> 
> the sched_pi_setprio trace point shows the "newprio" during a deboost:
> 
>   |futex sched_pi_setprio: comm=futex_requeue_p pid"34 oldprio˜ newprio=3D98
>   |futex sched_switch: prev_comm=futex_requeue_p prev_pid"34 prev_prio=120

pid=2234 got turned into pid"34 the same for other fields.

Sebastian

[tip:sched/core] sched, tracing: Fix trace_sched_pi_setprio() for deboosting

[tip-bot for Sebastian Andrzej Siewior]

Commit-ID:  4ff648decf4712d39f184fc2df3163f43975575a
Gitweb: https://git.kernel.org/tip/4ff648decf4712d39f184fc2df3163f43975575a
Author: Sebastian Andrzej Siewior 
AuthorDate: Thu, 24 May 2018 15:26:48 +0200
Committer:  Ingo Molnar 
CommitDate: Fri, 25 May 2018 08:04:01 +0200

sched, tracing: Fix trace_sched_pi_setprio() for deboosting

Since the following commit:

  b91473ff6e97 ("sched,tracing: Update trace_sched_pi_setprio()")

the sched_pi_setprio trace point shows the "newprio" during a deboost:

  |futex sched_pi_setprio: comm=futex_requeue_p pid"34 oldprio˜ newprio=3D98
  |futex sched_switch: prev_comm=futex_requeue_p prev_pid"34 prev_prio=120

This patch open codes __rt_effective_prio() in the tracepoint as the
'newprio' to get the old behaviour back / the correct priority:

  |futex sched_pi_setprio: comm=futex_requeue_p pid"20 oldprio˜ newprio=3D120
  |futex sched_switch: prev_comm=futex_requeue_p prev_pid"20 prev_prio=120

Peter suggested to open code the new priority so people using tracehook
could get the deadline data out.

Reported-by: Mansky Christian 
Signed-off-by: Sebastian Andrzej Siewior 
Signed-off-by: Peter Zijlstra (Intel) 
Cc: Linus Torvalds 
Cc: Peter Zijlstra 
Cc: Steven Rostedt 
Cc: Thomas Gleixner 
Fixes: b91473ff6e97 ("sched,tracing: Update trace_sched_pi_setprio()")
Link: http://lkml.kernel.org/r/20180524132647.gg6ziuogczdmj...@linutronix.de
Signed-off-by: Ingo Molnar 
---
 include/trace/events/sched.h | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/include/trace/events/sched.h b/include/trace/events/sched.h
index bc01e06bc716..0be866c91f62 100644
--- a/include/trace/events/sched.h
+++ b/include/trace/events/sched.h
@@ -435,7 +435,9 @@ TRACE_EVENT(sched_pi_setprio,
memcpy(__entry->comm, tsk->comm, TASK_COMM_LEN);
__entry->pid= tsk->pid;
__entry->oldprio= tsk->prio;
-   __entry->newprio= pi_task ? pi_task->prio : tsk->prio;
+   __entry->newprio= pi_task ?
+   min(tsk->normal_prio, pi_task->prio) :
+   tsk->normal_prio;
/* XXX SCHED_DEADLINE bits missing */
),
 

[tip:sched/core] sched, tracing: Fix trace_sched_pi_setprio() for deboosting

[tip-bot for Sebastian Andrzej Siewior]

Commit-ID:  4ff648decf4712d39f184fc2df3163f43975575a
Gitweb: https://git.kernel.org/tip/4ff648decf4712d39f184fc2df3163f43975575a
Author: Sebastian Andrzej Siewior 
AuthorDate: Thu, 24 May 2018 15:26:48 +0200
Committer:  Ingo Molnar 
CommitDate: Fri, 25 May 2018 08:04:01 +0200

sched, tracing: Fix trace_sched_pi_setprio() for deboosting

Since the following commit:

  b91473ff6e97 ("sched,tracing: Update trace_sched_pi_setprio()")

the sched_pi_setprio trace point shows the "newprio" during a deboost:

  |futex sched_pi_setprio: comm=futex_requeue_p pid"34 oldprio˜ newprio=3D98
  |futex sched_switch: prev_comm=futex_requeue_p prev_pid"34 prev_prio=120

This patch open codes __rt_effective_prio() in the tracepoint as the
'newprio' to get the old behaviour back / the correct priority:

  |futex sched_pi_setprio: comm=futex_requeue_p pid"20 oldprio˜ newprio=3D120
  |futex sched_switch: prev_comm=futex_requeue_p prev_pid"20 prev_prio=120

Peter suggested to open code the new priority so people using tracehook
could get the deadline data out.

Reported-by: Mansky Christian 
Signed-off-by: Sebastian Andrzej Siewior 
Signed-off-by: Peter Zijlstra (Intel) 
Cc: Linus Torvalds 
Cc: Peter Zijlstra 
Cc: Steven Rostedt 
Cc: Thomas Gleixner 
Fixes: b91473ff6e97 ("sched,tracing: Update trace_sched_pi_setprio()")
Link: http://lkml.kernel.org/r/20180524132647.gg6ziuogczdmj...@linutronix.de
Signed-off-by: Ingo Molnar 
---
 include/trace/events/sched.h | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/include/trace/events/sched.h b/include/trace/events/sched.h
index bc01e06bc716..0be866c91f62 100644
--- a/include/trace/events/sched.h
+++ b/include/trace/events/sched.h
@@ -435,7 +435,9 @@ TRACE_EVENT(sched_pi_setprio,
memcpy(__entry->comm, tsk->comm, TASK_COMM_LEN);
__entry->pid= tsk->pid;
__entry->oldprio= tsk->prio;
-   __entry->newprio= pi_task ? pi_task->prio : tsk->prio;
+   __entry->newprio= pi_task ?
+   min(tsk->normal_prio, pi_task->prio) :
+   tsk->normal_prio;
/* XXX SCHED_DEADLINE bits missing */
),