* [PATCH] tracing/sched: add 'next_policy' to trace_sched_switch
@ 2025-08-22 10:51 Xiang Gao
2025-08-22 14:02 ` Steven Rostedt
0 siblings, 1 reply; 3+ messages in thread
From: Xiang Gao @ 2025-08-22 10:51 UTC (permalink / raw)
To: rostedt, mhiramat
Cc: mathieu.desnoyers, andrii, mingo, oleg, akpm, gmonaco,
ricardo.neri-calderon, libo.chen, linux-kernel,
linux-trace-kernel, gaoxiang17
From: gaoxiang17 <gaoxiang17@xiaomi.com>
Sometimes, when analyzing some real-time process issues, it is necessary to know the sched policy.
Show up in the trace as:
113.457176: sched_switch: prev_comm=kcompactd0 prev_pid=30 prev_prio=120 prev_state=S ==> next_comm=kworker/u4:1 next_pid=27 next_prio=120 next_policy=0
113.457282: sched_switch: prev_comm=kworker/u4:1 prev_pid=27 prev_prio=120 prev_state=I ==> next_comm=swapper/0 next_pid=0 next_prio=120 next_policy=0
113.461166: sched_switch: prev_comm=swapper/0 prev_pid=0 prev_prio=120 prev_state=R ==> next_comm=kworker/u4:1 next_pid=27 next_prio=120 next_policy=0
Signed-off-by: gaoxiang17 <gaoxiang17@xiaomi.com>
---
include/trace/events/sched.h | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)
diff --git a/include/trace/events/sched.h b/include/trace/events/sched.h
index 7b2645b50e78..b416b7bafee4 100644
--- a/include/trace/events/sched.h
+++ b/include/trace/events/sched.h
@@ -234,6 +234,7 @@ TRACE_EVENT(sched_switch,
__array( char, next_comm, TASK_COMM_LEN )
__field( pid_t, next_pid )
__field( int, next_prio )
+ __field( unsigned int, next_policy )
),
TP_fast_assign(
@@ -244,10 +245,11 @@ TRACE_EVENT(sched_switch,
memcpy(__entry->next_comm, next->comm, TASK_COMM_LEN);
__entry->next_pid = next->pid;
__entry->next_prio = next->prio;
+ __entry->next_policy = next->policy;
/* XXX SCHED_DEADLINE */
),
- TP_printk("prev_comm=%s prev_pid=%d prev_prio=%d prev_state=%s%s ==> next_comm=%s next_pid=%d next_prio=%d",
+ TP_printk("prev_comm=%s prev_pid=%d prev_prio=%d prev_state=%s%s ==> next_comm=%s next_pid=%d next_prio=%d next_policy=%u",
__entry->prev_comm, __entry->prev_pid, __entry->prev_prio,
(__entry->prev_state & (TASK_REPORT_MAX - 1)) ?
@@ -263,7 +265,7 @@ TRACE_EVENT(sched_switch,
"R",
__entry->prev_state & TASK_REPORT_MAX ? "+" : "",
- __entry->next_comm, __entry->next_pid, __entry->next_prio)
+ __entry->next_comm, __entry->next_pid, __entry->next_prio, __entry->next_policy)
);
/*
--
2.34.1
^ permalink raw reply related [flat|nested] 3+ messages in thread* Re: [PATCH] tracing/sched: add 'next_policy' to trace_sched_switch 2025-08-22 10:51 [PATCH] tracing/sched: add 'next_policy' to trace_sched_switch Xiang Gao @ 2025-08-22 14:02 ` Steven Rostedt 2025-08-22 14:04 ` Steven Rostedt 0 siblings, 1 reply; 3+ messages in thread From: Steven Rostedt @ 2025-08-22 14:02 UTC (permalink / raw) To: Xiang Gao Cc: mhiramat, mathieu.desnoyers, andrii, mingo, oleg, akpm, gmonaco, ricardo.neri-calderon, libo.chen, linux-kernel, linux-trace-kernel, gaoxiang17 On Fri, 22 Aug 2025 18:51:13 +0800 Xiang Gao <gxxa03070307@gmail.com> wrote: > From: gaoxiang17 <gaoxiang17@xiaomi.com> > > Sometimes, when analyzing some real-time process issues, it is necessary to know the sched policy. > > Show up in the trace as: > > 113.457176: sched_switch: prev_comm=kcompactd0 prev_pid=30 prev_prio=120 prev_state=S ==> next_comm=kworker/u4:1 next_pid=27 next_prio=120 next_policy=0 > 113.457282: sched_switch: prev_comm=kworker/u4:1 prev_pid=27 prev_prio=120 prev_state=I ==> next_comm=swapper/0 next_pid=0 next_prio=120 next_policy=0 > 113.461166: sched_switch: prev_comm=swapper/0 prev_pid=0 prev_prio=120 prev_state=R ==> next_comm=kworker/u4:1 next_pid=27 next_prio=120 next_policy=0 > > Signed-off-by: gaoxiang17 <gaoxiang17@xiaomi.com> > --- > include/trace/events/sched.h | 6 ++++-- > 1 file changed, 4 insertions(+), 2 deletions(-) > > diff --git a/include/trace/events/sched.h b/include/trace/events/sched.h > index 7b2645b50e78..b416b7bafee4 100644 > --- a/include/trace/events/sched.h > +++ b/include/trace/events/sched.h > @@ -234,6 +234,7 @@ TRACE_EVENT(sched_switch, > __array( char, next_comm, TASK_COMM_LEN ) > __field( pid_t, next_pid ) > __field( int, next_prio ) > + __field( unsigned int, next_policy ) > ), > > TP_fast_assign( > @@ -244,10 +245,11 @@ TRACE_EVENT(sched_switch, > memcpy(__entry->next_comm, next->comm, TASK_COMM_LEN); > __entry->next_pid = next->pid; > __entry->next_prio = next->prio; > + __entry->next_policy = next->policy; > /* XXX SCHED_DEADLINE */ > ), > > - TP_printk("prev_comm=%s prev_pid=%d prev_prio=%d prev_state=%s%s ==> next_comm=%s next_pid=%d next_prio=%d", > + TP_printk("prev_comm=%s prev_pid=%d prev_prio=%d prev_state=%s%s ==> next_comm=%s next_pid=%d next_prio=%d next_policy=%u", > __entry->prev_comm, __entry->prev_pid, __entry->prev_prio, > > (__entry->prev_state & (TASK_REPORT_MAX - 1)) ? > @@ -263,7 +265,7 @@ TRACE_EVENT(sched_switch, > "R", > > __entry->prev_state & TASK_REPORT_MAX ? "+" : "", > - __entry->next_comm, __entry->next_pid, __entry->next_prio) > + __entry->next_comm, __entry->next_pid, __entry->next_prio, __entry->next_policy) I'm fine with this change, but I'm not sure how Peter feels about updating scheduler tracepoints. That said, why not show the policy name? TP_printk("prev_comm=%s prev_pid=%d prev_prio=%d prev_state=%s%s ==> next_comm=%s next_pid=%d next_prio=%d next_policy=%s", [..] __entry->next_comm, __entry->next_pid, __entry->next_prio, __print_symbolic(__entry->next_policy, { SCHED_NORMAL, "normal" }, { SCHED_FIFO, "FIFO" }, { SCHED_RR, "RR" }, { SCHED_BATCH, "batch" }, { SCHED_IDLE, "idle" }, { SCHED_DEADLINE, "deadline" }, { SCHED_EXT, "sched_ext"})) -- Steve > ); > > /* ^ permalink raw reply [flat|nested] 3+ messages in thread
* Re: [PATCH] tracing/sched: add 'next_policy' to trace_sched_switch 2025-08-22 14:02 ` Steven Rostedt @ 2025-08-22 14:04 ` Steven Rostedt 0 siblings, 0 replies; 3+ messages in thread From: Steven Rostedt @ 2025-08-22 14:04 UTC (permalink / raw) To: Xiang Gao Cc: mhiramat, mathieu.desnoyers, andrii, mingo, oleg, akpm, gmonaco, ricardo.neri-calderon, libo.chen, linux-kernel, linux-trace-kernel, gaoxiang17, Peter Zijlstra, Ingo Molnar, Juri Lelli, Vincent Guittot [ Adding scheduler maintainers ] On Fri, 22 Aug 2025 10:02:09 -0400 Steven Rostedt <rostedt@goodmis.org> wrote: > On Fri, 22 Aug 2025 18:51:13 +0800 > Xiang Gao <gxxa03070307@gmail.com> wrote: > > > From: gaoxiang17 <gaoxiang17@xiaomi.com> > > > > Sometimes, when analyzing some real-time process issues, it is necessary to know the sched policy. > > > > Show up in the trace as: > > > > 113.457176: sched_switch: prev_comm=kcompactd0 prev_pid=30 prev_prio=120 prev_state=S ==> next_comm=kworker/u4:1 next_pid=27 next_prio=120 next_policy=0 > > 113.457282: sched_switch: prev_comm=kworker/u4:1 prev_pid=27 prev_prio=120 prev_state=I ==> next_comm=swapper/0 next_pid=0 next_prio=120 next_policy=0 > > 113.461166: sched_switch: prev_comm=swapper/0 prev_pid=0 prev_prio=120 prev_state=R ==> next_comm=kworker/u4:1 next_pid=27 next_prio=120 next_policy=0 > > > > Signed-off-by: gaoxiang17 <gaoxiang17@xiaomi.com> > > --- > > include/trace/events/sched.h | 6 ++++-- > > 1 file changed, 4 insertions(+), 2 deletions(-) > > > > diff --git a/include/trace/events/sched.h b/include/trace/events/sched.h > > index 7b2645b50e78..b416b7bafee4 100644 > > --- a/include/trace/events/sched.h > > +++ b/include/trace/events/sched.h > > @@ -234,6 +234,7 @@ TRACE_EVENT(sched_switch, > > __array( char, next_comm, TASK_COMM_LEN ) > > __field( pid_t, next_pid ) > > __field( int, next_prio ) > > + __field( unsigned int, next_policy ) > > ), > > > > TP_fast_assign( > > @@ -244,10 +245,11 @@ TRACE_EVENT(sched_switch, > > memcpy(__entry->next_comm, next->comm, TASK_COMM_LEN); > > __entry->next_pid = next->pid; > > __entry->next_prio = next->prio; > > + __entry->next_policy = next->policy; > > /* XXX SCHED_DEADLINE */ > > ), > > > > - TP_printk("prev_comm=%s prev_pid=%d prev_prio=%d prev_state=%s%s ==> next_comm=%s next_pid=%d next_prio=%d", > > + TP_printk("prev_comm=%s prev_pid=%d prev_prio=%d prev_state=%s%s ==> next_comm=%s next_pid=%d next_prio=%d next_policy=%u", > > __entry->prev_comm, __entry->prev_pid, __entry->prev_prio, > > > > (__entry->prev_state & (TASK_REPORT_MAX - 1)) ? > > @@ -263,7 +265,7 @@ TRACE_EVENT(sched_switch, > > "R", > > > > __entry->prev_state & TASK_REPORT_MAX ? "+" : "", > > - __entry->next_comm, __entry->next_pid, __entry->next_prio) > > + __entry->next_comm, __entry->next_pid, __entry->next_prio, __entry->next_policy) > > > I'm fine with this change, but I'm not sure how Peter feels about updating > scheduler tracepoints. That said, why not show the policy name? Oh, and trace events are owned by the subsystem maintainers not the tracing maintainers. You need to Cc them. -- Steve > > TP_printk("prev_comm=%s prev_pid=%d prev_prio=%d prev_state=%s%s ==> next_comm=%s next_pid=%d next_prio=%d next_policy=%s", > [..] > __entry->next_comm, __entry->next_pid, __entry->next_prio, > __print_symbolic(__entry->next_policy, > { SCHED_NORMAL, "normal" }, > { SCHED_FIFO, "FIFO" }, > { SCHED_RR, "RR" }, > { SCHED_BATCH, "batch" }, > { SCHED_IDLE, "idle" }, > { SCHED_DEADLINE, "deadline" }, > { SCHED_EXT, "sched_ext"})) > > -- Steve > > > > > > > > ); > > > > /* > ^ permalink raw reply [flat|nested] 3+ messages in thread
end of thread, other threads:[~2025-08-22 14:04 UTC | newest] Thread overview: 3+ messages (download: mbox.gz follow: Atom feed -- links below jump to the message on this page -- 2025-08-22 10:51 [PATCH] tracing/sched: add 'next_policy' to trace_sched_switch Xiang Gao 2025-08-22 14:02 ` Steven Rostedt 2025-08-22 14:04 ` Steven Rostedt
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