public inbox for [email protected]
 help / color / mirror / Atom feed
* [PATCH 1/1] io_uring: fix locked_free_list caches_free()
@ 2021-02-23 21:53 Pavel Begunkov
  2021-02-23 21:56 ` Pavel Begunkov
  0 siblings, 1 reply; 2+ messages in thread
From: Pavel Begunkov @ 2021-02-23 21:53 UTC (permalink / raw)
  To: Jens Axboe, io-uring

Don't forget to zero locked_free_nr, it's not a disaster but makes it
attempting to flush it with extra locking when there is nothing in the
list. Also, don't traverse a potentially long list freeing requests
under spinlock, splice the list and do it afterwards.

Signed-off-by: Pavel Begunkov <[email protected]>
---
 fs/io_uring.c | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/fs/io_uring.c b/fs/io_uring.c
index bf9ad810c621..dedcf971e2d5 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -8710,12 +8710,13 @@ static void io_req_caches_free(struct io_ring_ctx *ctx, struct task_struct *tsk)
 		submit_state->free_reqs = 0;
 	}
 
-	io_req_cache_free(&submit_state->comp.free_list, NULL);
-
 	spin_lock_irq(&ctx->completion_lock);
-	io_req_cache_free(&submit_state->comp.locked_free_list, NULL);
+	list_splice_init(&cs->locked_free_list, &cs->free_list);
+	cs->locked_free_nr = 0;
 	spin_unlock_irq(&ctx->completion_lock);
 
+	io_req_cache_free(&submit_state->comp.free_list, NULL);
+
 	mutex_unlock(&ctx->uring_lock);
 }
 
-- 
2.24.0


^ permalink raw reply related	[flat|nested] 2+ messages in thread

* Re: [PATCH 1/1] io_uring: fix locked_free_list caches_free()
  2021-02-23 21:53 [PATCH 1/1] io_uring: fix locked_free_list caches_free() Pavel Begunkov
@ 2021-02-23 21:56 ` Pavel Begunkov
  0 siblings, 0 replies; 2+ messages in thread
From: Pavel Begunkov @ 2021-02-23 21:56 UTC (permalink / raw)
  To: Jens Axboe, io-uring

On 23/02/2021 21:53, Pavel Begunkov wrote:
> Don't forget to zero locked_free_nr, it's not a disaster but makes it
> attempting to flush it with extra locking when there is nothing in the
> list. Also, don't traverse a potentially long list freeing requests
> under spinlock, splice the list and do it afterwards.

Err, it gone totally wrong, will resend

> 
> Signed-off-by: Pavel Begunkov <[email protected]>
> ---
>  fs/io_uring.c | 7 ++++---
>  1 file changed, 4 insertions(+), 3 deletions(-)
> 
> diff --git a/fs/io_uring.c b/fs/io_uring.c
> index bf9ad810c621..dedcf971e2d5 100644
> --- a/fs/io_uring.c
> +++ b/fs/io_uring.c
> @@ -8710,12 +8710,13 @@ static void io_req_caches_free(struct io_ring_ctx *ctx, struct task_struct *tsk)
>  		submit_state->free_reqs = 0;
>  	}
>  
> -	io_req_cache_free(&submit_state->comp.free_list, NULL);
> -
>  	spin_lock_irq(&ctx->completion_lock);
> -	io_req_cache_free(&submit_state->comp.locked_free_list, NULL);
> +	list_splice_init(&cs->locked_free_list, &cs->free_list);
> +	cs->locked_free_nr = 0;
>  	spin_unlock_irq(&ctx->completion_lock);
>  
> +	io_req_cache_free(&submit_state->comp.free_list, NULL);
> +
>  	mutex_unlock(&ctx->uring_lock);
>  }
>  
> 

-- 
Pavel Begunkov

^ permalink raw reply	[flat|nested] 2+ messages in thread

end of thread, other threads:[~2021-02-23 22:01 UTC | newest]

Thread overview: 2+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2021-02-23 21:53 [PATCH 1/1] io_uring: fix locked_free_list caches_free() Pavel Begunkov
2021-02-23 21:56 ` Pavel Begunkov

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox