[PATCH] sched: Fix build for modules using set_tsk_need_resched()

[PATCH] sched: Fix build for modules using set_tsk_need_resched()

[Gabriele Monaco]

Commit adcc3bfa8806 ("sched: Adapt sched tracepoints for RV task model")
added a tracepoint to the need_resched action that can be triggered also
by set_tsk_need_resched.
This function was previously accessible from out-of-tree modules but
it's no longer available because the __trace_set_need_resched() symbol
is not exported (together with the tracepoint itself, which was exported
in a separate patch) and building such modules fails.

Export __trace_set_need_resched to modules to fix those build issues.

Fixes: adcc3bfa8806 ("sched: Adapt sched tracepoints for RV task model")
Cc: Phil Auld <pauld@redhat.com>
Signed-off-by: Gabriele Monaco <gmonaco@redhat.com>
---
 kernel/sched/core.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 60afadb6eede..a490d34cc65a 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -1136,6 +1136,7 @@ void __trace_set_need_resched(struct task_struct *curr, int tif)
 {
 	trace_sched_set_need_resched_tp(curr, smp_processor_id(), tif);
 }
+EXPORT_SYMBOL_GPL(__trace_set_need_resched);
 
 void resched_curr(struct rq *rq)
 {

base-commit: 0f61b1860cc3f52aef9036d7235ed1f017632193
-- 
2.52.0

Re: [PATCH] sched: Fix build for modules using set_tsk_need_resched()

[Phil Auld]

On Mon, Jan 12, 2026 at 03:04:13PM +0100 Gabriele Monaco wrote:
> Commit adcc3bfa8806 ("sched: Adapt sched tracepoints for RV task model")
> added a tracepoint to the need_resched action that can be triggered also
> by set_tsk_need_resched.
> This function was previously accessible from out-of-tree modules but
> it's no longer available because the __trace_set_need_resched() symbol
> is not exported (together with the tracepoint itself, which was exported
> in a separate patch) and building such modules fails.
> 
> Export __trace_set_need_resched to modules to fix those build issues.
> 
> Fixes: adcc3bfa8806 ("sched: Adapt sched tracepoints for RV task model")
> Cc: Phil Auld <pauld@redhat.com>
> Signed-off-by: Gabriele Monaco <gmonaco@redhat.com>
> ---
>  kernel/sched/core.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/kernel/sched/core.c b/kernel/sched/core.c
> index 60afadb6eede..a490d34cc65a 100644
> --- a/kernel/sched/core.c
> +++ b/kernel/sched/core.c
> @@ -1136,6 +1136,7 @@ void __trace_set_need_resched(struct task_struct *curr, int tif)
>  {
>  	trace_sched_set_need_resched_tp(curr, smp_processor_id(), tif);
>  }
> +EXPORT_SYMBOL_GPL(__trace_set_need_resched);
>  
>  void resched_curr(struct rq *rq)
>  {
> 
> base-commit: 0f61b1860cc3f52aef9036d7235ed1f017632193
> -- 
> 2.52.0
> 

Thanks Gabriele!  And good catch that the other patch is not sufficient.


Reviewed-by: Phil Auld <pauld@redhat.com>


-- 

[tip: sched/core] sched: Fix build for modules using set_tsk_need_resched()

[tip-bot2 for Gabriele Monaco]

The following commit has been merged into the sched/core branch of tip:

Commit-ID:     8d737320166bd145af70a3133a9964b00ca81cba
Gitweb:        https://git.kernel.org/tip/8d737320166bd145af70a3133a9964b00ca81cba
Author:        Gabriele Monaco <gmonaco@redhat.com>
AuthorDate:    Mon, 12 Jan 2026 15:04:13 +01:00
Committer:     Peter Zijlstra <peterz@infradead.org>
CommitterDate: Thu, 15 Jan 2026 22:41:26 +01:00

sched: Fix build for modules using set_tsk_need_resched()

Commit adcc3bfa8806 ("sched: Adapt sched tracepoints for RV task model")
added a tracepoint to the need_resched action that can be triggered also
by set_tsk_need_resched.
This function was previously accessible from out-of-tree modules but
it's no longer available because the __trace_set_need_resched() symbol
is not exported (together with the tracepoint itself, which was exported
in a separate patch) and building such modules fails.

Export __trace_set_need_resched to modules to fix those build issues.

Fixes: adcc3bfa8806 ("sched: Adapt sched tracepoints for RV task model")
Signed-off-by: Gabriele Monaco <gmonaco@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Phil Auld <pauld@redhat.com>
Link: https://patch.msgid.link/20260112140413.362202-1-gmonaco@redhat.com
---
 kernel/sched/core.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index b033f97..3cca012 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -1139,6 +1139,7 @@ void __trace_set_need_resched(struct task_struct *curr, int tif)
 {
 	trace_sched_set_need_resched_tp(curr, smp_processor_id(), tif);
 }
+EXPORT_SYMBOL_GPL(__trace_set_need_resched);
 
 void resched_curr(struct rq *rq)
 {

Re: [tip: sched/core] sched: Fix build for modules using set_tsk_need_resched()

[Phil Auld]

On Thu, Jan 15, 2026 at 09:44:19PM -0000 tip-bot2 for Gabriele Monaco wrote:
> The following commit has been merged into the sched/core branch of tip:
> 
> Commit-ID:     8d737320166bd145af70a3133a9964b00ca81cba
> Gitweb:        https://git.kernel.org/tip/8d737320166bd145af70a3133a9964b00ca81cba
> Author:        Gabriele Monaco <gmonaco@redhat.com>
> AuthorDate:    Mon, 12 Jan 2026 15:04:13 +01:00
> Committer:     Peter Zijlstra <peterz@infradead.org>
> CommitterDate: Thu, 15 Jan 2026 22:41:26 +01:00
>

Thank you for both of these, Peter!


Cheers,
Phil



> sched: Fix build for modules using set_tsk_need_resched()
> 
> Commit adcc3bfa8806 ("sched: Adapt sched tracepoints for RV task model")
> added a tracepoint to the need_resched action that can be triggered also
> by set_tsk_need_resched.
> This function was previously accessible from out-of-tree modules but
> it's no longer available because the __trace_set_need_resched() symbol
> is not exported (together with the tracepoint itself, which was exported
> in a separate patch) and building such modules fails.
> 
> Export __trace_set_need_resched to modules to fix those build issues.
> 
> Fixes: adcc3bfa8806 ("sched: Adapt sched tracepoints for RV task model")
> Signed-off-by: Gabriele Monaco <gmonaco@redhat.com>
> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
> Reviewed-by: Phil Auld <pauld@redhat.com>
> Link: https://patch.msgid.link/20260112140413.362202-1-gmonaco@redhat.com
> ---
>  kernel/sched/core.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/kernel/sched/core.c b/kernel/sched/core.c
> index b033f97..3cca012 100644
> --- a/kernel/sched/core.c
> +++ b/kernel/sched/core.c
> @@ -1139,6 +1139,7 @@ void __trace_set_need_resched(struct task_struct *curr, int tif)
>  {
>  	trace_sched_set_need_resched_tp(curr, smp_processor_id(), tif);
>  }
> +EXPORT_SYMBOL_GPL(__trace_set_need_resched);
>  
>  void resched_curr(struct rq *rq)
>  {
> 

-- 

Re: [tip: sched/core] sched: Fix build for modules using set_tsk_need_resched()

[Phil Auld]

Hi Peter and Gabriele,

On Thu, Jan 15, 2026 at 06:38:03PM -0500 Phil Auld wrote:
> On Thu, Jan 15, 2026 at 09:44:19PM -0000 tip-bot2 for Gabriele Monaco wrote:
> > The following commit has been merged into the sched/core branch of tip:
> > 
> > Commit-ID:     8d737320166bd145af70a3133a9964b00ca81cba
> > Gitweb:        https://git.kernel.org/tip/8d737320166bd145af70a3133a9964b00ca81cba
> > Author:        Gabriele Monaco <gmonaco@redhat.com>
> > AuthorDate:    Mon, 12 Jan 2026 15:04:13 +01:00
> > Committer:     Peter Zijlstra <peterz@infradead.org>
> > CommitterDate: Thu, 15 Jan 2026 22:41:26 +01:00
> >
> 
> Thank you for both of these, Peter!

Well, I think this one and the related one need to lose the _GPL because
they are called from things, like wake_up_process(), which are exported
without that restriction. This essentially adds _GPL to that and
anything else that ends up in resched_curr().

I prefer to add new symbols _GPL too but this case seems different.

Thoughts?

I can spin up a patch against tip:sched/core if you want it.


Cheers,
Phil

> 
> > sched: Fix build for modules using set_tsk_need_resched()
> > 
> > Commit adcc3bfa8806 ("sched: Adapt sched tracepoints for RV task model")
> > added a tracepoint to the need_resched action that can be triggered also
> > by set_tsk_need_resched.
> > This function was previously accessible from out-of-tree modules but
> > it's no longer available because the __trace_set_need_resched() symbol
> > is not exported (together with the tracepoint itself, which was exported
> > in a separate patch) and building such modules fails.
> > 
> > Export __trace_set_need_resched to modules to fix those build issues.
> > 
> > Fixes: adcc3bfa8806 ("sched: Adapt sched tracepoints for RV task model")
> > Signed-off-by: Gabriele Monaco <gmonaco@redhat.com>
> > Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
> > Reviewed-by: Phil Auld <pauld@redhat.com>
> > Link: https://patch.msgid.link/20260112140413.362202-1-gmonaco@redhat.com
> > ---
> >  kernel/sched/core.c | 1 +
> >  1 file changed, 1 insertion(+)
> > 
> > diff --git a/kernel/sched/core.c b/kernel/sched/core.c
> > index b033f97..3cca012 100644
> > --- a/kernel/sched/core.c
> > +++ b/kernel/sched/core.c
> > @@ -1139,6 +1139,7 @@ void __trace_set_need_resched(struct task_struct *curr, int tif)
> >  {
> >  	trace_sched_set_need_resched_tp(curr, smp_processor_id(), tif);
> >  }
> > +EXPORT_SYMBOL_GPL(__trace_set_need_resched);
> >  
> >  void resched_curr(struct rq *rq)
> >  {
> > 
> 
> -- 
> 

--