2024-01-26 15:27:17

by Levi Yun

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

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 <[email protected]>
---
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

2024-02-26 19:45:04

by Levi Yun

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

Gentle ping.

On Fri, Jan 26, 2024 at 3:26 PM Levi Yun <[email protected]> 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 <[email protected]>
> ---
> 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