Re: [PATCH] block/nvme: use AIO_WAIT_WHILE_UNLOCKED()

[Paolo Bonzini]

On 4/4/23 13:20, Stefan Hajnoczi wrote:
> A few Admin Queue commands are submitted during nvme_file_open(). They
> are synchronous since device initialization cannot continue until the
> commands complete.
>
> AIO_WAIT_WHILE() is currently used, but the block/nvme.c code actually
> doesn't rely on the AioContext lock. Replace it with
> AIO_WAIT_WHILE_UNLOCKED(NULL, condition). There is no change in behavior
> and the dependency on the AioContext lock is eliminated.
>
> This is a step towards removing the AioContext lock.
>
> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
> ---
>   block/nvme.c | 3 +--
>   1 file changed, 1 insertion(+), 2 deletions(-)
>
> diff --git a/block/nvme.c b/block/nvme.c
> index 5b744c2bda..829b9c04db 100644
> --- a/block/nvme.c
> +++ b/block/nvme.c
> @@ -512,7 +512,6 @@ static int nvme_admin_cmd_sync(BlockDriverState *bs, 
> NvmeCmd *cmd)
>   {
>       BDRVNVMeState *s = bs->opaque;
>       NVMeQueuePair *q = s->queues[INDEX_ADMIN];
> -    AioContext *aio_context = bdrv_get_aio_context(bs);
>       NVMeRequest *req;
>       int ret = -EINPROGRESS;
>       req = nvme_get_free_req_nowait(q);
> @@ -521,7 +520,7 @@ static int nvme_admin_cmd_sync(BlockDriverState *bs, 
> NvmeCmd *cmd)
>       }
>       nvme_submit_command(q, req, cmd, nvme_admin_cmd_sync_cb, &ret);
>   
> -    AIO_WAIT_WHILE(aio_context, ret == -EINPROGRESS);
> +    AIO_WAIT_WHILE_UNLOCKED(NULL, ret == -EINPROGRESS);
>       return ret;
>   }


Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>