Re: [Qemu-devel] [PATCH v6 21/25] replay: replay BH for IDE trim operation

[John Snow]

On 09/12/2018 04:19 AM, Pavel Dovgalyuk wrote:
> This patch makes IDE trim BH deterministic, because it affects
> the device state. Therefore its invocation should be replayed
> instead of running at the random moment.
> 
> Signed-off-by: Pavel Dovgalyuk <pavel.dovga...@ispras.ru>
> Reviewed-by: Paolo Bonzini <pbonz...@redhat.com>
> ---
>  hw/ide/core.c |    3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/hw/ide/core.c b/hw/ide/core.c
> index 2c62efc..04e22e7 100644
> --- a/hw/ide/core.c
> +++ b/hw/ide/core.c
> @@ -35,6 +35,7 @@
>  #include "sysemu/block-backend.h"
>  #include "qapi/error.h"
>  #include "qemu/cutils.h"
> +#include "sysemu/replay.h"
>  
>  #include "hw/ide/internal.h"
>  #include "trace.h"
> @@ -479,7 +480,7 @@ static void ide_issue_trim_cb(void *opaque, int ret)
>  done:
>      iocb->aiocb = NULL;
>      if (iocb->bh) {
> -        qemu_bh_schedule(iocb->bh);
> +        replay_bh_schedule_event(iocb->bh);
>      }
>  }
>  
> 
> 

Just passing by: Why do we need to change this call, but nothing else in
IDE?

I don't mind conceptually, but it's odd to me that of all the calls I
make in this emulator that change state somewhere that this is the only
one you need to hijack for the replay feature.

Is this a necessarily complete change?

--js