[PATCH] kswapd: Replace try_to_freeze to kthread_freezable_should_stop.

[PATCH] kswapd: Replace try_to_freeze to kthread_freezable_should_stop.

[Levi Yun]

Instead of using try_to_freeze, use kthread_freezable_should_stop in
kswapd.
By this, we can avoid unnecessary freezing when kswapd should stop.

Signed-off-by: Levi Yun <ppbuk5246@gmail.com>
---
 mm/vmscan.c | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/mm/vmscan.c b/mm/vmscan.c
index 4f9c854ce6cc..1f139830b26f 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -6796,6 +6796,7 @@ static int balance_pgdat(pg_data_t *pgdat, int order, int highest_zoneidx)
 		bool raise_priority = true;
 		bool balanced;
 		bool ret;
+		bool was_frozen;

 		sc.reclaim_idx = highest_zoneidx;

@@ -6894,9 +6895,9 @@ static int balance_pgdat(pg_data_t *pgdat, int order, int highest_zoneidx)

 		/* Check if kswapd should be suspending */
 		__fs_reclaim_release(_THIS_IP_);
-		ret = try_to_freeze();
+		ret = kthread_freezable_should_stop(&was_frozen);
 		__fs_reclaim_acquire(_THIS_IP_);
-		if (ret || kthread_should_stop())
+		if (was_frozen || ret)
 			break;

 		/*
@@ -7102,7 +7103,7 @@ static int kswapd(void *p)
 	WRITE_ONCE(pgdat->kswapd_highest_zoneidx, MAX_NR_ZONES);
 	atomic_set(&pgdat->nr_writeback_throttled, 0);
 	for ( ; ; ) {
-		bool ret;
+		bool was_frozen;

 		alloc_order = reclaim_order = READ_ONCE(pgdat->kswapd_order);
 		highest_zoneidx = kswapd_highest_zoneidx(pgdat,
@@ -7119,15 +7120,14 @@ static int kswapd(void *p)
 		WRITE_ONCE(pgdat->kswapd_order, 0);
 		WRITE_ONCE(pgdat->kswapd_highest_zoneidx, MAX_NR_ZONES);

-		ret = try_to_freeze();
-		if (kthread_should_stop())
+		if (kthread_freezable_should_stop(&was_frozen))
 			break;

 		/*
 		 * We can speed up thawing tasks if we don't call balance_pgdat
 		 * after returning from the refrigerator
 		 */
-		if (ret)
+		if (was_frozen)
 			continue;

 		/*
--
2.39.2

Re: [PATCH] kswapd: Replace try_to_freeze to kthread_freezable_should_stop.

[Yun Levi]

Gentle ping.

On Fri, Jan 26, 2024 at 3:26 PM Levi Yun <ppbuk5246@gmail.com> wrote:
>
> Instead of using try_to_freeze, use kthread_freezable_should_stop in
> kswapd.
> By this, we can avoid unnecessary freezing when kswapd should stop.
>
> Signed-off-by: Levi Yun <ppbuk5246@gmail.com>
> ---
>  mm/vmscan.c | 12 ++++++------
>  1 file changed, 6 insertions(+), 6 deletions(-)
>
> diff --git a/mm/vmscan.c b/mm/vmscan.c
> index 4f9c854ce6cc..1f139830b26f 100644
> --- a/mm/vmscan.c
> +++ b/mm/vmscan.c
> @@ -6796,6 +6796,7 @@ static int balance_pgdat(pg_data_t *pgdat, int order, int highest_zoneidx)
>                 bool raise_priority = true;
>                 bool balanced;
>                 bool ret;
> +               bool was_frozen;
>
>                 sc.reclaim_idx = highest_zoneidx;
>
> @@ -6894,9 +6895,9 @@ static int balance_pgdat(pg_data_t *pgdat, int order, int highest_zoneidx)
>
>                 /* Check if kswapd should be suspending */
>                 __fs_reclaim_release(_THIS_IP_);
> -               ret = try_to_freeze();
> +               ret = kthread_freezable_should_stop(&was_frozen);
>                 __fs_reclaim_acquire(_THIS_IP_);
> -               if (ret || kthread_should_stop())
> +               if (was_frozen || ret)
>                         break;
>
>                 /*
> @@ -7102,7 +7103,7 @@ static int kswapd(void *p)
>         WRITE_ONCE(pgdat->kswapd_highest_zoneidx, MAX_NR_ZONES);
>         atomic_set(&pgdat->nr_writeback_throttled, 0);
>         for ( ; ; ) {
> -               bool ret;
> +               bool was_frozen;
>
>                 alloc_order = reclaim_order = READ_ONCE(pgdat->kswapd_order);
>                 highest_zoneidx = kswapd_highest_zoneidx(pgdat,
> @@ -7119,15 +7120,14 @@ static int kswapd(void *p)
>                 WRITE_ONCE(pgdat->kswapd_order, 0);
>                 WRITE_ONCE(pgdat->kswapd_highest_zoneidx, MAX_NR_ZONES);
>
> -               ret = try_to_freeze();
> -               if (kthread_should_stop())
> +               if (kthread_freezable_should_stop(&was_frozen))
>                         break;
>
>                 /*
>                  * We can speed up thawing tasks if we don't call balance_pgdat
>                  * after returning from the refrigerator
>                  */
> -               if (ret)
> +               if (was_frozen)
>                         continue;
>
>                 /*
> --
> 2.39.2