[Qemu-devel] [PATCH 06/10] blockjob: move iostatus reset inside block_job_user_resume

Paolo Bonzini posted 10 patches 8 years, 10 months ago
There is a newer version of this series
[Qemu-devel] [PATCH 06/10] blockjob: move iostatus reset inside block_job_user_resume
Posted by Paolo Bonzini 8 years, 10 months ago
Outside blockjob.c, the block_job_iostatus_reset function is used once
in the monitor and once in BlockBackend.  When we introduce the block
job mutex, block_job_iostatus_reset's client is going to be the block
layer (for which blockjob.c will take the block job mutex) rather than
the monitor (which will take the block job mutex by itself).

The monitor's call to block_job_iostatus_reset from the monitor comes
just before the sole call to block_job_user_resume, so reset the
iostatus directly from block_job_iostatus_reset.  This will avoid
the need to introduce separate block_job_iostatus_reset and
block_job_iostatus_reset_locked APIs.

After making this change, move the function together with the others
that were moved in the previous patch.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
 blockdev.c |  1 -
 blockjob.c | 11 ++++++-----
 2 files changed, 6 insertions(+), 6 deletions(-)

diff --git a/blockdev.c b/blockdev.c
index c5b2c2c..fbc376b 100644
--- a/blockdev.c
+++ b/blockdev.c
@@ -3726,7 +3726,6 @@ void qmp_block_job_resume(const char *device, Error **errp)
     }
 
     trace_qmp_block_job_resume(job);
-    block_job_iostatus_reset(job);
     block_job_user_resume(job);
     aio_context_release(aio_context);
 }
diff --git a/blockjob.c b/blockjob.c
index c5f1d19..c9cb5b1 100644
--- a/blockjob.c
+++ b/blockjob.c
@@ -481,6 +481,7 @@ void block_job_user_resume(BlockJob *job)
 {
     if (job && job->user_paused && job->pause_count > 0) {
         job->user_paused = false;
+        block_job_iostatus_reset(job);
         block_job_resume(job);
     }
 }
@@ -496,11 +497,6 @@ void block_job_cancel(BlockJob *job)
     }
 }
 
-void block_job_iostatus_reset(BlockJob *job)
-{
-    job->iostatus = BLOCK_DEVICE_IO_STATUS_OK;
-}
-
 static int block_job_finish_sync(BlockJob *job,
                                  void (*finish)(BlockJob *, Error **errp),
                                  Error **errp)
@@ -751,6 +747,11 @@ void block_job_yield(BlockJob *job)
     block_job_pause_point(job);
 }
 
+void block_job_iostatus_reset(BlockJob *job)
+{
+    job->iostatus = BLOCK_DEVICE_IO_STATUS_OK;
+}
+
 void block_job_event_ready(BlockJob *job)
 {
     job->ready = true;
-- 
2.9.3



Re: [Qemu-devel] [PATCH 06/10] blockjob: move iostatus reset inside block_job_user_resume
Posted by John Snow 8 years, 10 months ago

On 03/23/2017 01:39 PM, Paolo Bonzini wrote:
> Outside blockjob.c, the block_job_iostatus_reset function is used once
> in the monitor and once in BlockBackend.  When we introduce the block
> job mutex, block_job_iostatus_reset's client is going to be the block
> layer (for which blockjob.c will take the block job mutex) rather than
> the monitor (which will take the block job mutex by itself).
> 

Ah, sure. So we leave the block-backend call alone, here. We're moving
it from "public API" to "specifically block-layer API" to help
facilitate different mutex semantics. OK.

> The monitor's call to block_job_iostatus_reset from the monitor comes
> just before the sole call to block_job_user_resume, so reset the
> iostatus directly from block_job_iostatus_reset.  This will avoid
> the need to introduce separate block_job_iostatus_reset and
> block_job_iostatus_reset_locked APIs.
> 
> After making this change, move the function together with the others
> that were moved in the previous patch.
> 
> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Reviewed-by: John Snow <jsnow@redhat.com>

> ---
>  blockdev.c |  1 -
>  blockjob.c | 11 ++++++-----
>  2 files changed, 6 insertions(+), 6 deletions(-)
> 
> diff --git a/blockdev.c b/blockdev.c
> index c5b2c2c..fbc376b 100644
> --- a/blockdev.c
> +++ b/blockdev.c
> @@ -3726,7 +3726,6 @@ void qmp_block_job_resume(const char *device, Error **errp)
>      }
>  
>      trace_qmp_block_job_resume(job);
> -    block_job_iostatus_reset(job);
>      block_job_user_resume(job);
>      aio_context_release(aio_context);
>  }
> diff --git a/blockjob.c b/blockjob.c
> index c5f1d19..c9cb5b1 100644
> --- a/blockjob.c
> +++ b/blockjob.c
> @@ -481,6 +481,7 @@ void block_job_user_resume(BlockJob *job)
>  {
>      if (job && job->user_paused && job->pause_count > 0) {
>          job->user_paused = false;
> +        block_job_iostatus_reset(job);
>          block_job_resume(job);
>      }
>  }
> @@ -496,11 +497,6 @@ void block_job_cancel(BlockJob *job)
>      }
>  }
>  
> -void block_job_iostatus_reset(BlockJob *job)
> -{
> -    job->iostatus = BLOCK_DEVICE_IO_STATUS_OK;
> -}
> -
>  static int block_job_finish_sync(BlockJob *job,
>                                   void (*finish)(BlockJob *, Error **errp),
>                                   Error **errp)
> @@ -751,6 +747,11 @@ void block_job_yield(BlockJob *job)
>      block_job_pause_point(job);
>  }
>  
> +void block_job_iostatus_reset(BlockJob *job)
> +{
> +    job->iostatus = BLOCK_DEVICE_IO_STATUS_OK;
> +}
> +
>  void block_job_event_ready(BlockJob *job)
>  {
>      job->ready = true;
> 

Re: [Qemu-devel] [PATCH 06/10] blockjob: move iostatus reset inside block_job_user_resume
Posted by Stefan Hajnoczi 8 years, 10 months ago
On Thu, Mar 23, 2017 at 06:39:24PM +0100, Paolo Bonzini wrote:
> Outside blockjob.c, the block_job_iostatus_reset function is used once
> in the monitor and once in BlockBackend.  When we introduce the block
> job mutex, block_job_iostatus_reset's client is going to be the block
> layer (for which blockjob.c will take the block job mutex) rather than
> the monitor (which will take the block job mutex by itself).
> 
> The monitor's call to block_job_iostatus_reset from the monitor comes
> just before the sole call to block_job_user_resume, so reset the
> iostatus directly from block_job_iostatus_reset.  This will avoid
> the need to introduce separate block_job_iostatus_reset and
> block_job_iostatus_reset_locked APIs.
> 
> After making this change, move the function together with the others
> that were moved in the previous patch.
> 
> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
> ---
>  blockdev.c |  1 -
>  blockjob.c | 11 ++++++-----
>  2 files changed, 6 insertions(+), 6 deletions(-)

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>