Re: [Qemu-devel] [RFC PATCH v13 15/21] bottom halves: introduce bh call function

[Paolo Bonzini <pbonzini@redhat.com>]

On 06/05/2015 16:04, Pavel Dovgalyuk wrote:
> This patch introduces aio_bh_call function. It is used to execute
> bottom halves as callbacks without adding them to the queue.
> 
> Signed-off-by: Pavel Dovgalyuk <pavel.dovgaluk@ispras.ru>
> ---
>  async.c             |    8 +++++++-
>  include/block/aio.h |    5 +++++
>  2 files changed, 12 insertions(+), 1 deletions(-)
> 
> diff --git a/async.c b/async.c
> index 46d9e63..734c76c 100644
> --- a/async.c
> +++ b/async.c
> @@ -59,6 +59,12 @@ QEMUBH *aio_bh_new(AioContext *ctx, QEMUBHFunc *cb, void *opaque)
>      return bh;
>  }
>  
> +void aio_bh_call(void *opaque)
> +{
> +    QEMUBH *bh = (QEMUBH *)opaque;

This can have a QEMUBH * argument.  I can fix it when committing.

> +    bh->cb(bh->opaque);
> +}
> +
>  /* Multiple occurrences of aio_bh_poll cannot be called concurrently */
>  int aio_bh_poll(AioContext *ctx)
>  {
> @@ -82,7 +88,7 @@ int aio_bh_poll(AioContext *ctx)
>              if (!bh->idle)
>                  ret = 1;
>              bh->idle = 0;
> -            bh->cb(bh->opaque);
> +            aio_bh_call(bh);
>          }
>      }
>  
> diff --git a/include/block/aio.h b/include/block/aio.h
> index d2bb423..b498704 100644
> --- a/include/block/aio.h
> +++ b/include/block/aio.h
> @@ -157,6 +157,11 @@ QEMUBH *aio_bh_new(AioContext *ctx, QEMUBHFunc *cb, void *opaque);
>  void aio_notify(AioContext *ctx);
>  
>  /**
> + * aio_bh_call: Executes callback function of the specified BH.
> + */
> +void aio_bh_call(void *opaque);
> +
> +/**
>   * aio_bh_poll: Poll bottom halves for an AioContext.
>   *
>   * These are internal functions used by the QEMU main loop.
> 

Works for me!  I am not sure why patch 16 works though. :)  I'll ponder
on it, in the meanwhile some extra explanation from you would be welcome...

Paolo