Re: [PATCH v4 05/12] job: @force parameter for job_cancel_sync()

[Eric Blake <eblake@redhat.com>]

On Tue, Sep 07, 2021 at 02:42:38PM +0200, Hanna Reitz wrote:
> Callers should be able to specify whether they want job_cancel_sync() to
> force-cancel the job or not.
> 
> In fact, almost all invocations do not care about consistency of the
> result and just want the job to terminate as soon as possible, so they
> should pass force=true.  The replication block driver is the exception,
> specifically the active commit job it runs.
> 
> As for job_cancel_sync_all(), all callers want it to force-cancel all
> jobs, because that is the point of it: To cancel all remaining jobs as
> quickly as possible (generally on process termination).  So make it
> invoke job_cancel_sync() with force=true.
> 
> This changes some iotest outputs, because quitting qemu while a mirror
> job is active will now lead to it being cancelled instead of completed,
> which is what we want.  (Cancelling a READY mirror job with force=false
> may take an indefinite amount of time, which we do not want when
> quitting.  If users want consistent results, they must have all jobs be
> done before they quit qemu.)
> 
> Buglink: https://gitlab.com/qemu-project/qemu/-/issues/462
> Signed-off-by: Hanna Reitz <hreitz@redhat.com>
> ---
>  include/qemu/job.h                    | 10 ++---
>  block/replication.c                   |  4 +-
>  blockdev.c                            |  4 +-
>  job.c                                 | 18 ++++++--
>  tests/unit/test-blockjob.c            |  2 +-
>  tests/qemu-iotests/109.out            | 60 +++++++++++----------------
>  tests/qemu-iotests/tests/qsd-jobs.out |  2 +-
>  7 files changed, 50 insertions(+), 50 deletions(-)
> 

Reviewed-by: Eric Blake <eblake@redhat.com>

-- 
Eric Blake, Principal Software Engineer
Red Hat, Inc.           +1-919-301-3266
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