| Message ID | 20220926093214.506243-17-eesposit@redhat.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | job: replace AioContext lock with job_mutex | expand |
Am 26.09.2022 um 11:32 hat Emanuele Giuseppe Esposito geschrieben: > iostatus is the only field (together with .job) that needs > protection using the job mutex. > > It is set in the main loop (GLOBAL_STATE functions) but read > in I/O code (block_job_error_action). > > In order to protect it, change block_job_iostatus_set_err > to block_job_iostatus_set_err_locked(), always called under > job lock. > > Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> > Reviewed-by: Kevin Wolf <kwolf@redhat.com> > Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru> > --- > block/mirror.c | 7 +++++-- > blockjob.c | 5 +++-- > 2 files changed, 8 insertions(+), 4 deletions(-) > > diff --git a/block/mirror.c b/block/mirror.c > index c6bf7f40ce..7e32ee1d31 100644 > --- a/block/mirror.c > +++ b/block/mirror.c > @@ -893,7 +893,7 @@ static int coroutine_fn mirror_run(Job *job, Error **errp) > MirrorBlockJob *s = container_of(job, MirrorBlockJob, common.job); > BlockDriverState *bs = s->mirror_top_bs->backing->bs; > BlockDriverState *target_bs = blk_bs(s->target); > - bool need_drain = true; > + bool need_drain = true, iostatus; iostatus isn't really a bool, it's BlockDeviceIoStatus. > int64_t length; > int64_t target_length; > BlockDriverInfo bdi; > @@ -1016,8 +1016,11 @@ static int coroutine_fn mirror_run(Job *job, Error **errp) > * We do so every BLKOCK_JOB_SLICE_TIME nanoseconds, or when there is > * an error, or when the source is clean, whichever comes first. */ > delta = qemu_clock_get_ns(QEMU_CLOCK_REALTIME) - s->last_pause_ns; > + WITH_JOB_LOCK_GUARD() { > + iostatus = s->common.iostatus; > + } > if (delta < BLOCK_JOB_SLICE_TIME && > - s->common.iostatus == BLOCK_DEVICE_IO_STATUS_OK) { > + iostatus == BLOCK_DEVICE_IO_STATUS_OK) { Your code actually happens to work because the one value that you compare it against is BLOCK_DEVICE_IO_STATUS_OK, which is 0, so it maps to false and everything else to true, but... it's still not right. :-) > if (s->in_flight >= MAX_IN_FLIGHT || s->buf_free_count == 0 || > (cnt == 0 && s->in_flight > 0)) { > trace_mirror_yield(s, cnt, s->buf_free_count, s->in_flight); Kevin
diff --git a/block/mirror.c b/block/mirror.c index c6bf7f40ce..7e32ee1d31 100644 --- a/block/mirror.c +++ b/block/mirror.c @@ -893,7 +893,7 @@ static int coroutine_fn mirror_run(Job *job, Error **errp) MirrorBlockJob *s = container_of(job, MirrorBlockJob, common.job); BlockDriverState *bs = s->mirror_top_bs->backing->bs; BlockDriverState *target_bs = blk_bs(s->target); - bool need_drain = true; + bool need_drain = true, iostatus; int64_t length; int64_t target_length; BlockDriverInfo bdi; @@ -1016,8 +1016,11 @@ static int coroutine_fn mirror_run(Job *job, Error **errp) * We do so every BLKOCK_JOB_SLICE_TIME nanoseconds, or when there is * an error, or when the source is clean, whichever comes first. */ delta = qemu_clock_get_ns(QEMU_CLOCK_REALTIME) - s->last_pause_ns; + WITH_JOB_LOCK_GUARD() { + iostatus = s->common.iostatus; + } if (delta < BLOCK_JOB_SLICE_TIME && - s->common.iostatus == BLOCK_DEVICE_IO_STATUS_OK) { + iostatus == BLOCK_DEVICE_IO_STATUS_OK) { if (s->in_flight >= MAX_IN_FLIGHT || s->buf_free_count == 0 || (cnt == 0 && s->in_flight > 0)) { trace_mirror_yield(s, cnt, s->buf_free_count, s->in_flight); diff --git a/blockjob.c b/blockjob.c index d8fb5311c7..d04f804001 100644 --- a/blockjob.c +++ b/blockjob.c @@ -363,7 +363,8 @@ BlockJobInfo *block_job_query(BlockJob *job, Error **errp) return block_job_query_locked(job, errp); } -static void block_job_iostatus_set_err(BlockJob *job, int error) +/* Called with job lock held */ +static void block_job_iostatus_set_err_locked(BlockJob *job, int error) { if (job->iostatus == BLOCK_DEVICE_IO_STATUS_OK) { job->iostatus = error == ENOSPC ? BLOCK_DEVICE_IO_STATUS_NOSPACE : @@ -577,8 +578,8 @@ BlockErrorAction block_job_error_action(BlockJob *job, BlockdevOnError on_err, */ job->job.user_paused = true; } + block_job_iostatus_set_err_locked(job, error); } - block_job_iostatus_set_err(job, error); } return action; }