[v3] parallels: Refactor the code of images checks and fix a bug

[PATCH v3 8/8] parallels: Replace qemu_co_mutex_lock by WITH_QEMU_LOCK_GUARD

Posted by Alexander Ivanov 3 years, 5 months ago

Replace the way we use mutex in parallels_co_check() for simplier
and less error prone code.

Signed-off-by: Alexander Ivanov <alexander.ivanov@virtuozzo.com>
---
v2: Fix an incorrect usage of WITH_QEMU_LOCK_GUARD.
v3: Fix commit message.

 block/parallels.c | 26 ++++++++++++--------------
 1 file changed, 12 insertions(+), 14 deletions(-)

diff --git a/block/parallels.c b/block/parallels.c
index d0364182bb..e124a8bb7d 100644
--- a/block/parallels.c
+++ b/block/parallels.c
@@ -553,24 +553,22 @@ static int coroutine_fn parallels_co_check(BlockDriverState *bs,
     BDRVParallelsState *s = bs->opaque;
     int ret;
 
-    qemu_co_mutex_lock(&s->lock);
+    WITH_QEMU_LOCK_GUARD(&s->lock) {
+        parallels_check_unclean(bs, res, fix);
 
-    parallels_check_unclean(bs, res, fix);
+        ret = parallels_check_outside_image(bs, res, fix);
+        if (ret < 0) {
+            return ret;
+        }
 
-    ret = parallels_check_outside_image(bs, res, fix);
-    if (ret < 0) {
-        goto out;
-    }
-
-    ret = parallels_check_leak(bs, res, fix);
-    if (ret < 0) {
-        goto out;
-    }
+        ret = parallels_check_leak(bs, res, fix);
+        if (ret < 0) {
+            return ret;
+        }
 
-    parallels_collect_statistics(bs, res, fix);
+        parallels_collect_statistics(bs, res, fix);
 
-out:
-    qemu_co_mutex_unlock(&s->lock);
+    }
 
     ret = bdrv_co_flush(bs);
     if (ret < 0) {
-- 
2.34.1

Re: [PATCH v3 8/8] parallels: Replace qemu_co_mutex_lock by WITH_QEMU_LOCK_GUARD

Posted by Vladimir Sementsov-Ogievskiy 3 years, 5 months ago

On 8/15/22 12:02, Alexander Ivanov wrote:
> Replace the way we use mutex in parallels_co_check() for simplier
> and less error prone code.
> 
> Signed-off-by: Alexander Ivanov <alexander.ivanov@virtuozzo.com>
> ---
> v2: Fix an incorrect usage of WITH_QEMU_LOCK_GUARD.
> v3: Fix commit message.
> 
>   block/parallels.c | 26 ++++++++++++--------------
>   1 file changed, 12 insertions(+), 14 deletions(-)
> 
> diff --git a/block/parallels.c b/block/parallels.c
> index d0364182bb..e124a8bb7d 100644
> --- a/block/parallels.c
> +++ b/block/parallels.c
> @@ -553,24 +553,22 @@ static int coroutine_fn parallels_co_check(BlockDriverState *bs,
>       BDRVParallelsState *s = bs->opaque;
>       int ret;
>   
> -    qemu_co_mutex_lock(&s->lock);
> +    WITH_QEMU_LOCK_GUARD(&s->lock) {
> +        parallels_check_unclean(bs, res, fix);
>   
> -    parallels_check_unclean(bs, res, fix);
> +        ret = parallels_check_outside_image(bs, res, fix);
> +        if (ret < 0) {
> +            return ret;
> +        }
>   
> -    ret = parallels_check_outside_image(bs, res, fix);
> -    if (ret < 0) {
> -        goto out;
> -    }
> -
> -    ret = parallels_check_leak(bs, res, fix);
> -    if (ret < 0) {
> -        goto out;
> -    }
> +        ret = parallels_check_leak(bs, res, fix);
> +        if (ret < 0) {
> +            return ret;
> +        }
>   
> -    parallels_collect_statistics(bs, res, fix);
> +        parallels_collect_statistics(bs, res, fix);
>   
> -out:
> -    qemu_co_mutex_unlock(&s->lock);
> +    }
>   
>       ret = bdrv_co_flush(bs);
>       if (ret < 0) {

Aha, and here you silently fix the problem I noted in patch 3. Still, all patches should be correct, so this should be rebased onto fixed patch 3.

The final look of parallels_co_check is good.


-- 
Best regards,
Vladimir