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* [PATCH] mm/migrate: report RCU-tasks quiescent states in migrate_pages_batch()
@ 2026-07-27 13:50 Breno Leitao
  2026-07-27 14:24 ` Zi Yan
                   ` (3 more replies)
  0 siblings, 4 replies; 6+ messages in thread
From: Breno Leitao @ 2026-07-27 13:50 UTC (permalink / raw)
  To: Andrew Morton, David Hildenbrand, Zi Yan, Matthew Brost,
	Joshua Hahn, Rakie Kim, Byungchul Park, Gregory Price, Ying Huang,
	Alistair Popple, paulmck
  Cc: linux-mm, linux-kernel, kernel-team, Breno Leitao

migrate_pages_batch() unmaps each folio before moving it, and every
unmap runs the mmu_notifier invalidate callbacks.  On KVM hosts
try_to_migrate() ends up in kvm_mmu_notifier_invalidate_range_start() ->
tdp_mmu_zap_leafs(), which is expensive, so unmapping a large batch keeps
the CPU busy for a long time.

The loop already calls cond_resched(), but on PREEMPTION kernels that is
a no-op, and involuntary preemption is not a Tasks-RCU quiescent state.

A long batch therefore never reports a quiescent state, and the
migrating task (e.g. kcompactd) becomes a Tasks-RCU holdout, stalling the
Tasks-RCU grace period for minutes, which is common at Meta fleet:

  INFO: rcu_tasks detected stalls on tasks:
  0000000055349ecc: .. nvcsw: 1157401/1157401 holdout: 1 idle_cpu: -1/56 task:kcompactd0      state:R  running task
  Call Trace:
   tdp_mmu_zap_leafs
   tdp_mmu_next_root
   gfn_to_pfn_cache_invalidate_start
   kvm_mmu_notifier_invalidate_range_start
   __mmu_notifier_invalidate_range_start
   try_to_migrate_one
   try_to_migrate
   migrate_pages_batch
   migrate_pages
   compact_zone
   compact_node
   kcompactd
   kthread

Use cond_resched_tasks_rcu_qs() so a quiescent state is reported even
when cond_resched() does nothing.

PS: This has also been discussed at [1]

Link: https://lore.kernel.org/all/amdWVTs0WKOxguxP@gmail.com/ [1]
Signed-off-by: Breno Leitao <leitao@debian.org>
---
 mm/migrate.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/mm/migrate.c b/mm/migrate.c
index ab15a4dddd047..b937cbd764808 100644
--- a/mm/migrate.c
+++ b/mm/migrate.c
@@ -1843,7 +1843,7 @@ static int migrate_pages_batch(struct list_head *from,
 			is_thp = folio_test_pmd_mappable(folio);
 			nr_pages = folio_nr_pages(folio);
 
-			cond_resched();
+			cond_resched_tasks_rcu_qs();
 
 			/*
 			 * The rare folio on the deferred split list should

---
base-commit: c5e32e86ca02b003f86e095d379b38148999293d
change-id: 20260727-kcompact-ff0550fc0ebb

Best regards,
--  
Breno Leitao <leitao@debian.org>



^ permalink raw reply related	[flat|nested] 6+ messages in thread

* Re: [PATCH] mm/migrate: report RCU-tasks quiescent states in migrate_pages_batch()
  2026-07-27 13:50 [PATCH] mm/migrate: report RCU-tasks quiescent states in migrate_pages_batch() Breno Leitao
@ 2026-07-27 14:24 ` Zi Yan
  2026-07-27 15:57 ` Gregory Price
                   ` (2 subsequent siblings)
  3 siblings, 0 replies; 6+ messages in thread
From: Zi Yan @ 2026-07-27 14:24 UTC (permalink / raw)
  To: Breno Leitao
  Cc: Andrew Morton, David Hildenbrand, Matthew Brost, Joshua Hahn,
	Rakie Kim, Byungchul Park, Gregory Price, Ying Huang,
	Alistair Popple, paulmck, linux-mm, linux-kernel, kernel-team

On 27 Jul 2026, at 9:50, Breno Leitao wrote:

> migrate_pages_batch() unmaps each folio before moving it, and every
> unmap runs the mmu_notifier invalidate callbacks.  On KVM hosts
> try_to_migrate() ends up in kvm_mmu_notifier_invalidate_range_start() ->
> tdp_mmu_zap_leafs(), which is expensive, so unmapping a large batch keeps
> the CPU busy for a long time.
>
> The loop already calls cond_resched(), but on PREEMPTION kernels that is
> a no-op, and involuntary preemption is not a Tasks-RCU quiescent state.
>
> A long batch therefore never reports a quiescent state, and the
> migrating task (e.g. kcompactd) becomes a Tasks-RCU holdout, stalling the
> Tasks-RCU grace period for minutes, which is common at Meta fleet:
>
>   INFO: rcu_tasks detected stalls on tasks:
>   0000000055349ecc: .. nvcsw: 1157401/1157401 holdout: 1 idle_cpu: -1/56 task:kcompactd0      state:R  running task
>   Call Trace:
>    tdp_mmu_zap_leafs
>    tdp_mmu_next_root
>    gfn_to_pfn_cache_invalidate_start
>    kvm_mmu_notifier_invalidate_range_start
>    __mmu_notifier_invalidate_range_start
>    try_to_migrate_one
>    try_to_migrate
>    migrate_pages_batch
>    migrate_pages
>    compact_zone
>    compact_node
>    kcompactd
>    kthread
>
> Use cond_resched_tasks_rcu_qs() so a quiescent state is reported even
> when cond_resched() does nothing.

The explanation looks good to me.

Acked-by: Zi Yan <ziy@nvidia.com>

BTW, Sashiko complained about hugetlb path, but hugetlb does not batch
migration, so there should not be an issue like this one.

>
> PS: This has also been discussed at [1]
>
> Link: https://lore.kernel.org/all/amdWVTs0WKOxguxP@gmail.com/ [1]
> Signed-off-by: Breno Leitao <leitao@debian.org>
> ---
>  mm/migrate.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/mm/migrate.c b/mm/migrate.c
> index ab15a4dddd047..b937cbd764808 100644
> --- a/mm/migrate.c
> +++ b/mm/migrate.c
> @@ -1843,7 +1843,7 @@ static int migrate_pages_batch(struct list_head *from,
>  			is_thp = folio_test_pmd_mappable(folio);
>  			nr_pages = folio_nr_pages(folio);
>
> -			cond_resched();
> +			cond_resched_tasks_rcu_qs();
>
>  			/*
>  			 * The rare folio on the deferred split list should
>
> ---
> base-commit: c5e32e86ca02b003f86e095d379b38148999293d
> change-id: 20260727-kcompact-ff0550fc0ebb
>
> Best regards,
> --
> Breno Leitao <leitao@debian.org>


Best Regards,
Yan, Zi


^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: [PATCH] mm/migrate: report RCU-tasks quiescent states in migrate_pages_batch()
  2026-07-27 13:50 [PATCH] mm/migrate: report RCU-tasks quiescent states in migrate_pages_batch() Breno Leitao
  2026-07-27 14:24 ` Zi Yan
@ 2026-07-27 15:57 ` Gregory Price
  2026-07-27 18:39 ` Paul E. McKenney
  2026-07-27 20:49 ` Andrew Morton
  3 siblings, 0 replies; 6+ messages in thread
From: Gregory Price @ 2026-07-27 15:57 UTC (permalink / raw)
  To: Breno Leitao
  Cc: Andrew Morton, David Hildenbrand, Zi Yan, Matthew Brost,
	Joshua Hahn, Rakie Kim, Byungchul Park, Ying Huang,
	Alistair Popple, paulmck, linux-mm, linux-kernel, kernel-team

On Mon, Jul 27, 2026 at 06:50:19AM -0700, Breno Leitao wrote:
> migrate_pages_batch() unmaps each folio before moving it, and every
> unmap runs the mmu_notifier invalidate callbacks.  On KVM hosts
> try_to_migrate() ends up in kvm_mmu_notifier_invalidate_range_start() ->
> tdp_mmu_zap_leafs(), which is expensive, so unmapping a large batch keeps
> the CPU busy for a long time.
> 
> The loop already calls cond_resched(), but on PREEMPTION kernels that is
> a no-op, and involuntary preemption is not a Tasks-RCU quiescent state.
> 
> A long batch therefore never reports a quiescent state, and the
> migrating task (e.g. kcompactd) becomes a Tasks-RCU holdout, stalling the
> Tasks-RCU grace period for minutes, which is common at Meta fleet:
> 
>   INFO: rcu_tasks detected stalls on tasks:
>   0000000055349ecc: .. nvcsw: 1157401/1157401 holdout: 1 idle_cpu: -1/56 task:kcompactd0      state:R  running task
>   Call Trace:
>    tdp_mmu_zap_leafs
>    tdp_mmu_next_root
>    gfn_to_pfn_cache_invalidate_start
>    kvm_mmu_notifier_invalidate_range_start
>    __mmu_notifier_invalidate_range_start
>    try_to_migrate_one
>    try_to_migrate
>    migrate_pages_batch
>    migrate_pages
>    compact_zone
>    compact_node
>    kcompactd
>    kthread
> 
> Use cond_resched_tasks_rcu_qs() so a quiescent state is reported even
> when cond_resched() does nothing.
> 
> PS: This has also been discussed at [1]
> 
> Link: https://lore.kernel.org/all/amdWVTs0WKOxguxP@gmail.com/ [1]
> Signed-off-by: Breno Leitao <leitao@debian.org>

Reviewed-by: Gregory Price <gourry@gourry.net>



^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: [PATCH] mm/migrate: report RCU-tasks quiescent states in migrate_pages_batch()
  2026-07-27 13:50 [PATCH] mm/migrate: report RCU-tasks quiescent states in migrate_pages_batch() Breno Leitao
  2026-07-27 14:24 ` Zi Yan
  2026-07-27 15:57 ` Gregory Price
@ 2026-07-27 18:39 ` Paul E. McKenney
  2026-07-27 20:49 ` Andrew Morton
  3 siblings, 0 replies; 6+ messages in thread
From: Paul E. McKenney @ 2026-07-27 18:39 UTC (permalink / raw)
  To: Breno Leitao
  Cc: Andrew Morton, David Hildenbrand, Zi Yan, Matthew Brost,
	Joshua Hahn, Rakie Kim, Byungchul Park, Gregory Price, Ying Huang,
	Alistair Popple, linux-mm, linux-kernel, kernel-team

On Mon, Jul 27, 2026 at 06:50:19AM -0700, Breno Leitao wrote:
> migrate_pages_batch() unmaps each folio before moving it, and every
> unmap runs the mmu_notifier invalidate callbacks.  On KVM hosts
> try_to_migrate() ends up in kvm_mmu_notifier_invalidate_range_start() ->
> tdp_mmu_zap_leafs(), which is expensive, so unmapping a large batch keeps
> the CPU busy for a long time.
> 
> The loop already calls cond_resched(), but on PREEMPTION kernels that is
> a no-op, and involuntary preemption is not a Tasks-RCU quiescent state.
> 
> A long batch therefore never reports a quiescent state, and the
> migrating task (e.g. kcompactd) becomes a Tasks-RCU holdout, stalling the
> Tasks-RCU grace period for minutes, which is common at Meta fleet:
> 
>   INFO: rcu_tasks detected stalls on tasks:
>   0000000055349ecc: .. nvcsw: 1157401/1157401 holdout: 1 idle_cpu: -1/56 task:kcompactd0      state:R  running task
>   Call Trace:
>    tdp_mmu_zap_leafs
>    tdp_mmu_next_root
>    gfn_to_pfn_cache_invalidate_start
>    kvm_mmu_notifier_invalidate_range_start
>    __mmu_notifier_invalidate_range_start
>    try_to_migrate_one
>    try_to_migrate
>    migrate_pages_batch
>    migrate_pages
>    compact_zone
>    compact_node
>    kcompactd
>    kthread
> 
> Use cond_resched_tasks_rcu_qs() so a quiescent state is reported even
> when cond_resched() does nothing.
> 
> PS: This has also been discussed at [1]
> 
> Link: https://lore.kernel.org/all/amdWVTs0WKOxguxP@gmail.com/ [1]
> Signed-off-by: Breno Leitao <leitao@debian.org>

Very good!

Reviewed-by: Paul E. McKenney <paulmck@kernel.org>

> ---
>  mm/migrate.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/mm/migrate.c b/mm/migrate.c
> index ab15a4dddd047..b937cbd764808 100644
> --- a/mm/migrate.c
> +++ b/mm/migrate.c
> @@ -1843,7 +1843,7 @@ static int migrate_pages_batch(struct list_head *from,
>  			is_thp = folio_test_pmd_mappable(folio);
>  			nr_pages = folio_nr_pages(folio);
>  
> -			cond_resched();
> +			cond_resched_tasks_rcu_qs();
>  
>  			/*
>  			 * The rare folio on the deferred split list should
> 
> ---
> base-commit: c5e32e86ca02b003f86e095d379b38148999293d
> change-id: 20260727-kcompact-ff0550fc0ebb
> 
> Best regards,
> --  
> Breno Leitao <leitao@debian.org>
> 


^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: [PATCH] mm/migrate: report RCU-tasks quiescent states in migrate_pages_batch()
  2026-07-27 13:50 [PATCH] mm/migrate: report RCU-tasks quiescent states in migrate_pages_batch() Breno Leitao
                   ` (2 preceding siblings ...)
  2026-07-27 18:39 ` Paul E. McKenney
@ 2026-07-27 20:49 ` Andrew Morton
  2026-07-27 21:14   ` Paul E. McKenney
  3 siblings, 1 reply; 6+ messages in thread
From: Andrew Morton @ 2026-07-27 20:49 UTC (permalink / raw)
  To: Breno Leitao
  Cc: David Hildenbrand, Zi Yan, Matthew Brost, Joshua Hahn, Rakie Kim,
	Byungchul Park, Gregory Price, Ying Huang, Alistair Popple,
	paulmck, linux-mm, linux-kernel, kernel-team

On Mon, 27 Jul 2026 06:50:19 -0700 Breno Leitao <leitao@debian.org> wrote:

> migrate_pages_batch() unmaps each folio before moving it, and every
> unmap runs the mmu_notifier invalidate callbacks.  On KVM hosts
> try_to_migrate() ends up in kvm_mmu_notifier_invalidate_range_start() ->
> tdp_mmu_zap_leafs(), which is expensive, so unmapping a large batch keeps
> the CPU busy for a long time.
> 
> The loop already calls cond_resched(), but on PREEMPTION kernels that is
> a no-op, and involuntary preemption is not a Tasks-RCU quiescent state.
> 
> A long batch therefore never reports a quiescent state, and the
> migrating task (e.g. kcompactd) becomes a Tasks-RCU holdout, stalling the
> Tasks-RCU grace period for minutes, which is common at Meta fleet:
> 
>   INFO: rcu_tasks detected stalls on tasks:
>   0000000055349ecc: .. nvcsw: 1157401/1157401 holdout: 1 idle_cpu: -1/56 task:kcompactd0      state:R  running task
>   Call Trace:
>    tdp_mmu_zap_leafs
>    tdp_mmu_next_root
>    gfn_to_pfn_cache_invalidate_start
>    kvm_mmu_notifier_invalidate_range_start
>    __mmu_notifier_invalidate_range_start
>    try_to_migrate_one
>    try_to_migrate
>    migrate_pages_batch
>    migrate_pages
>    compact_zone
>    compact_node
>    kcompactd
>    kthread

Well I doubt if users of 7.1 kernels and earlier want to see this.  So
a Fixes: and a cc:stable are needed.  The affected code is quite old
and might even predate the addition of cond_resched_tasks_rcu_qs().  So
I can't begin to suggest a Fixes: target.  Maybe omit it and let the
-stable team figure it out ;)

> --- a/mm/migrate.c
> +++ b/mm/migrate.c
> @@ -1843,7 +1843,7 @@ static int migrate_pages_batch(struct list_head *from,
>  			is_thp = folio_test_pmd_mappable(folio);
>  			nr_pages = folio_nr_pages(folio);
>  
> -			cond_resched();
> +			cond_resched_tasks_rcu_qs();
>  

Totally off-topic but why the heck was that implemented as a macro. 
Which invokes another macro and another and another and turtles all the
way down.  End result:

   do { do { if (!((false)) && ({ do { __attribute__((__noreturn__)) extern void __compiletime_assert_606(void) __attribute__((__error__("Unsupported access size for {READ,WRITE}_ONCE()."))); if (!((sizeof(((current))->rcu_tasks_holdout) == sizeof(char) || sizeof(((current))->rcu_tasks_holdout) == sizeof(short) || sizeof(((current))->rcu_tasks_holdout) == sizeof(int) || sizeof(((current))->rcu_tasks_holdout) == sizeof(long)) || sizeof(((current))->rcu_tasks_holdout) == sizeof(long long))) __compiletime_assert_606(); } while (0); (*(const volatile __typeof_unqual__(((current))->rcu_tasks_holdout) *)&(((current))->rcu_tasks_holdout)); })) do { do { __attribute__((__noreturn__)) extern void __compiletime_assert_607(void) __attribute__((__error__("Unsupported access size for {READ,WRITE}_ONCE()."))); if (!((sizeof(((current))->rcu_tasks_holdout) == sizeof(char) || sizeof(((current))->rcu_tasks_holdout) == sizeof(short) || sizeof(((current))->rcu_tasks_holdout) == sizeof(int) || s
 izeof(((
 current))->rcu_tasks_holdout) == sizeof(long)) || sizeof(((current))->rcu_tasks_holdout) == sizeof(long long))) __compiletime_assert_607(); } while (0); do { *(volatile typeof(((current))->rcu_tasks_holdout) *)&(((current))->rcu_tasks_holdout) = (false); } while (0); } while (0); } while (0); ({ __might_resched("mm/migrate.c", 1846, 0); _cond_resched(); }); } while (0);


How much nicer would it be to have

static inline void cond_resched_tasks_rcu_qs(void)
{
	if (some brief and efficient test)
		some_slow_uninlined_thing();
}



^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: [PATCH] mm/migrate: report RCU-tasks quiescent states in migrate_pages_batch()
  2026-07-27 20:49 ` Andrew Morton
@ 2026-07-27 21:14   ` Paul E. McKenney
  0 siblings, 0 replies; 6+ messages in thread
From: Paul E. McKenney @ 2026-07-27 21:14 UTC (permalink / raw)
  To: Andrew Morton
  Cc: Breno Leitao, David Hildenbrand, Zi Yan, Matthew Brost,
	Joshua Hahn, Rakie Kim, Byungchul Park, Gregory Price, Ying Huang,
	Alistair Popple, linux-mm, linux-kernel, kernel-team

On Mon, Jul 27, 2026 at 01:49:50PM -0700, Andrew Morton wrote:
> On Mon, 27 Jul 2026 06:50:19 -0700 Breno Leitao <leitao@debian.org> wrote:
> 
> > migrate_pages_batch() unmaps each folio before moving it, and every
> > unmap runs the mmu_notifier invalidate callbacks.  On KVM hosts
> > try_to_migrate() ends up in kvm_mmu_notifier_invalidate_range_start() ->
> > tdp_mmu_zap_leafs(), which is expensive, so unmapping a large batch keeps
> > the CPU busy for a long time.
> > 
> > The loop already calls cond_resched(), but on PREEMPTION kernels that is
> > a no-op, and involuntary preemption is not a Tasks-RCU quiescent state.
> > 
> > A long batch therefore never reports a quiescent state, and the
> > migrating task (e.g. kcompactd) becomes a Tasks-RCU holdout, stalling the
> > Tasks-RCU grace period for minutes, which is common at Meta fleet:
> > 
> >   INFO: rcu_tasks detected stalls on tasks:
> >   0000000055349ecc: .. nvcsw: 1157401/1157401 holdout: 1 idle_cpu: -1/56 task:kcompactd0      state:R  running task
> >   Call Trace:
> >    tdp_mmu_zap_leafs
> >    tdp_mmu_next_root
> >    gfn_to_pfn_cache_invalidate_start
> >    kvm_mmu_notifier_invalidate_range_start
> >    __mmu_notifier_invalidate_range_start
> >    try_to_migrate_one
> >    try_to_migrate
> >    migrate_pages_batch
> >    migrate_pages
> >    compact_zone
> >    compact_node
> >    kcompactd
> >    kthread
> 
> Well I doubt if users of 7.1 kernels and earlier want to see this.  So
> a Fixes: and a cc:stable are needed.  The affected code is quite old
> and might even predate the addition of cond_resched_tasks_rcu_qs().  So
> I can't begin to suggest a Fixes: target.  Maybe omit it and let the
> -stable team figure it out ;)
> 
> > --- a/mm/migrate.c
> > +++ b/mm/migrate.c
> > @@ -1843,7 +1843,7 @@ static int migrate_pages_batch(struct list_head *from,
> >  			is_thp = folio_test_pmd_mappable(folio);
> >  			nr_pages = folio_nr_pages(folio);
> >  
> > -			cond_resched();
> > +			cond_resched_tasks_rcu_qs();
> >  
> 
> Totally off-topic but why the heck was that implemented as a macro. 
> Which invokes another macro and another and another and turtles all the
> way down.  End result:
> 
>    do { do { if (!((false)) && ({ do { __attribute__((__noreturn__)) extern void __compiletime_assert_606(void) __attribute__((__error__("Unsupported access size for {READ,WRITE}_ONCE()."))); if (!((sizeof(((current))->rcu_tasks_holdout) == sizeof(char) || sizeof(((current))->rcu_tasks_holdout) == sizeof(short) || sizeof(((current))->rcu_tasks_holdout) == sizeof(int) || sizeof(((current))->rcu_tasks_holdout) == sizeof(long)) || sizeof(((current))->rcu_tasks_holdout) == sizeof(long long))) __compiletime_assert_606(); } while (0); (*(const volatile __typeof_unqual__(((current))->rcu_tasks_holdout) *)&(((current))->rcu_tasks_holdout)); })) do { do { __attribute__((__noreturn__)) extern void __compiletime_assert_607(void) __attribute__((__error__("Unsupported access size for {READ,WRITE}_ONCE()."))); if (!((sizeof(((current))->rcu_tasks_holdout) == sizeof(char) || sizeof(((current))->rcu_tasks_holdout) == sizeof(short) || sizeof(((current))->rcu_tasks_holdout) == sizeof(int) || sizeof(((
>  current))->rcu_tasks_holdout) == sizeof(long)) || sizeof(((current))->rcu_tasks_holdout) == sizeof(long long))) __compiletime_assert_607(); } while (0); do { *(volatile typeof(((current))->rcu_tasks_holdout) *)&(((current))->rcu_tasks_holdout) = (false); } while (0); } while (0); } while (0); ({ __might_resched("mm/migrate.c", 1846, 0); _cond_resched(); }); } while (0);
> 
> 
> How much nicer would it be to have
> 
> static inline void cond_resched_tasks_rcu_qs(void)
> {
> 	if (some brief and efficient test)
> 		some_slow_uninlined_thing();
> }

Sigh.  It used to be so simple, then people wanted error checks in
READ_ONCE() and WRITE_ONCE().  ;-)

The point of rcu_tasks_classic_qs() being a macro was to avoid #include
hell.  But maybe cond_resched_tasks_rcu_qs() can be a static inline,
as shown below.  It builds, so it must be perfect, right?  On the other
hand, does that really help, given that cond_resched_tasks_rcu_qs()
gets inlined?

							Thanx, Paul

------------------------------------------------------------------------

diff --git a/include/linux/rcupdate.h b/include/linux/rcupdate.h
index c77b1e02a93cca..9a741ce0588575 100644
--- a/include/linux/rcupdate.h
+++ b/include/linux/rcupdate.h
@@ -217,15 +217,15 @@ static inline void exit_tasks_rcu_finish(void) { }
 /**
  * cond_resched_tasks_rcu_qs - Report potential quiescent states to RCU
  *
- * This macro resembles cond_resched(), except that it is defined to
+ * This function resembles cond_resched(), except that it is defined to
  * report potential quiescent states to RCU-tasks even if the cond_resched()
  * machinery were to be shut off, as some advocate for PREEMPTION kernels.
  */
-#define cond_resched_tasks_rcu_qs() \
-do { \
-	rcu_tasks_qs(current, false); \
-	cond_resched(); \
-} while (0)
+static inline void cond_resched_tasks_rcu_qs(void)
+{
+	rcu_tasks_qs(current, false);
+	cond_resched();
+}
 
 /**
  * rcu_softirq_qs_periodic - Report RCU and RCU-Tasks quiescent states


^ permalink raw reply related	[flat|nested] 6+ messages in thread

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2026-07-27 13:50 [PATCH] mm/migrate: report RCU-tasks quiescent states in migrate_pages_batch() Breno Leitao
2026-07-27 14:24 ` Zi Yan
2026-07-27 15:57 ` Gregory Price
2026-07-27 18:39 ` Paul E. McKenney
2026-07-27 20:49 ` Andrew Morton
2026-07-27 21:14   ` Paul E. McKenney

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