Now that the API offers also _locked() functions, take advantage
of it and give also the caller control to take the lock and call
_locked functions.
This makes sense especially when we have for loops, because it
makes no sense to have:
for(job = job_next(); ...)
where each job_next() takes the lock internally.
Instead we want
JOB_LOCK_GUARD();
for(job = job_next_locked(); ...)
Note: at this stage, job_{lock/unlock} and job lock guard macros
are *nop*.
Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
---
block.c | 20 +++++++++++-------
blockdev.c | 12 ++++++++---
blockjob.c | 52 +++++++++++++++++++++++++++++++---------------
job-qmp.c | 4 +++-
job.c | 5 ++++-
monitor/qmp-cmds.c | 7 +++++--
qemu-img.c | 41 +++++++++++++++++++++---------------
7 files changed, 93 insertions(+), 48 deletions(-)
diff --git a/block.c b/block.c
index 2c00dddd80..d0db104d71 100644
--- a/block.c
+++ b/block.c
@@ -4978,9 +4978,12 @@ static void bdrv_close(BlockDriverState *bs)
void bdrv_close_all(void)
{
- assert(job_next(NULL) == NULL);
GLOBAL_STATE_CODE();
+ WITH_JOB_LOCK_GUARD() {
+ assert(job_next_locked(NULL) == NULL);
+ }
+
/* Drop references from requests still in flight, such as canceled block
* jobs whose AIO context has not been polled yet */
bdrv_drain_all();
@@ -6165,13 +6168,16 @@ XDbgBlockGraph *bdrv_get_xdbg_block_graph(Error **errp)
}
}
- for (job = block_job_next(NULL); job; job = block_job_next(job)) {
- GSList *el;
+ WITH_JOB_LOCK_GUARD() {
+ for (job = block_job_next_locked(NULL); job;
+ job = block_job_next_locked(job)) {
+ GSList *el;
- xdbg_graph_add_node(gr, job, X_DBG_BLOCK_GRAPH_NODE_TYPE_BLOCK_JOB,
- job->job.id);
- for (el = job->nodes; el; el = el->next) {
- xdbg_graph_add_edge(gr, job, (BdrvChild *)el->data);
+ xdbg_graph_add_node(gr, job, X_DBG_BLOCK_GRAPH_NODE_TYPE_BLOCK_JOB,
+ job->job.id);
+ for (el = job->nodes; el; el = el->next) {
+ xdbg_graph_add_edge(gr, job, (BdrvChild *)el->data);
+ }
}
}
diff --git a/blockdev.c b/blockdev.c
index 71f793c4ab..5b79093155 100644
--- a/blockdev.c
+++ b/blockdev.c
@@ -150,12 +150,15 @@ void blockdev_mark_auto_del(BlockBackend *blk)
return;
}
- for (job = block_job_next(NULL); job; job = block_job_next(job)) {
+ JOB_LOCK_GUARD();
+
+ for (job = block_job_next_locked(NULL); job;
+ job = block_job_next_locked(job)) {
if (block_job_has_bdrv(job, blk_bs(blk))) {
AioContext *aio_context = job->job.aio_context;
aio_context_acquire(aio_context);
- job_cancel(&job->job, false);
+ job_cancel_locked(&job->job, false);
aio_context_release(aio_context);
}
@@ -3745,7 +3748,10 @@ BlockJobInfoList *qmp_query_block_jobs(Error **errp)
BlockJobInfoList *head = NULL, **tail = &head;
BlockJob *job;
- for (job = block_job_next(NULL); job; job = block_job_next(job)) {
+ JOB_LOCK_GUARD();
+
+ for (job = block_job_next_locked(NULL); job;
+ job = block_job_next_locked(job)) {
BlockJobInfo *value;
AioContext *aio_context;
diff --git a/blockjob.c b/blockjob.c
index 0d59aba439..bce05a9096 100644
--- a/blockjob.c
+++ b/blockjob.c
@@ -99,7 +99,9 @@ static char *child_job_get_parent_desc(BdrvChild *c)
static void child_job_drained_begin(BdrvChild *c)
{
BlockJob *job = c->opaque;
- job_pause(&job->job);
+ WITH_JOB_LOCK_GUARD() {
+ job_pause_locked(&job->job);
+ }
}
static bool child_job_drained_poll(BdrvChild *c)
@@ -111,8 +113,10 @@ static bool child_job_drained_poll(BdrvChild *c)
/* An inactive or completed job doesn't have any pending requests. Jobs
* with !job->busy are either already paused or have a pause point after
* being reentered, so no job driver code will run before they pause. */
- if (!job->busy || job_is_completed(job)) {
- return false;
+ WITH_JOB_LOCK_GUARD() {
+ if (!job->busy || job_is_completed_locked(job)) {
+ return false;
+ }
}
/* Otherwise, assume that it isn't fully stopped yet, but allow the job to
@@ -127,7 +131,9 @@ static bool child_job_drained_poll(BdrvChild *c)
static void child_job_drained_end(BdrvChild *c, int *drained_end_counter)
{
BlockJob *job = c->opaque;
- job_resume(&job->job);
+ WITH_JOB_LOCK_GUARD() {
+ job_resume_locked(&job->job);
+ }
}
static bool child_job_can_set_aio_ctx(BdrvChild *c, AioContext *ctx,
@@ -475,13 +481,15 @@ void *block_job_create(const char *job_id, const BlockJobDriver *driver,
job->ready_notifier.notify = block_job_event_ready;
job->idle_notifier.notify = block_job_on_idle;
- notifier_list_add(&job->job.on_finalize_cancelled,
- &job->finalize_cancelled_notifier);
- notifier_list_add(&job->job.on_finalize_completed,
- &job->finalize_completed_notifier);
- notifier_list_add(&job->job.on_pending, &job->pending_notifier);
- notifier_list_add(&job->job.on_ready, &job->ready_notifier);
- notifier_list_add(&job->job.on_idle, &job->idle_notifier);
+ WITH_JOB_LOCK_GUARD() {
+ notifier_list_add(&job->job.on_finalize_cancelled,
+ &job->finalize_cancelled_notifier);
+ notifier_list_add(&job->job.on_finalize_completed,
+ &job->finalize_completed_notifier);
+ notifier_list_add(&job->job.on_pending, &job->pending_notifier);
+ notifier_list_add(&job->job.on_ready, &job->ready_notifier);
+ notifier_list_add(&job->job.on_idle, &job->idle_notifier);
+ }
error_setg(&job->blocker, "block device is in use by block job: %s",
job_type_str(&job->job));
@@ -493,7 +501,10 @@ void *block_job_create(const char *job_id, const BlockJobDriver *driver,
bdrv_op_unblock(bs, BLOCK_OP_TYPE_DATAPLANE, job->blocker);
- if (!block_job_set_speed(job, speed, errp)) {
+ WITH_JOB_LOCK_GUARD() {
+ ret = block_job_set_speed_locked(job, speed, errp);
+ }
+ if (!ret) {
goto fail;
}
@@ -524,7 +535,9 @@ void block_job_user_resume(Job *job)
{
BlockJob *bjob = container_of(job, BlockJob, job);
GLOBAL_STATE_CODE();
- block_job_iostatus_reset(bjob);
+ WITH_JOB_LOCK_GUARD() {
+ block_job_iostatus_reset_locked(bjob);
+ }
}
BlockErrorAction block_job_error_action(BlockJob *job, BlockdevOnError on_err,
@@ -558,10 +571,15 @@ BlockErrorAction block_job_error_action(BlockJob *job, BlockdevOnError on_err,
action);
}
if (action == BLOCK_ERROR_ACTION_STOP) {
- if (!job->job.user_paused) {
- job_pause(&job->job);
- /* make the pause user visible, which will be resumed from QMP. */
- job->job.user_paused = true;
+ WITH_JOB_LOCK_GUARD() {
+ if (!job->job.user_paused) {
+ job_pause_locked(&job->job);
+ /*
+ * make the pause user visible, which will be
+ * resumed from QMP.
+ */
+ job->job.user_paused = true;
+ }
}
block_job_iostatus_set_err(job, error);
}
diff --git a/job-qmp.c b/job-qmp.c
index ac11a6c23c..cfaf34ffb7 100644
--- a/job-qmp.c
+++ b/job-qmp.c
@@ -194,7 +194,9 @@ JobInfoList *qmp_query_jobs(Error **errp)
JobInfoList *head = NULL, **tail = &head;
Job *job;
- for (job = job_next(NULL); job; job = job_next(job)) {
+ JOB_LOCK_GUARD();
+
+ for (job = job_next_locked(NULL); job; job = job_next_locked(job)) {
JobInfo *value;
AioContext *aio_context;
diff --git a/job.c b/job.c
index de3d368086..9c8792c9e8 100644
--- a/job.c
+++ b/job.c
@@ -1046,11 +1046,14 @@ static void job_completed_txn_abort_locked(Job *job)
/* Called with job_mutex held, but releases it temporarily */
static int job_prepare_locked(Job *job)
{
+ int ret;
+
GLOBAL_STATE_CODE();
if (job->ret == 0 && job->driver->prepare) {
job_unlock();
- job->ret = job->driver->prepare(job);
+ ret = job->driver->prepare(job);
job_lock();
+ job->ret = ret;
job_update_rc_locked(job);
}
return job->ret;
diff --git a/monitor/qmp-cmds.c b/monitor/qmp-cmds.c
index 1ebb89f46c..1897ed7a13 100644
--- a/monitor/qmp-cmds.c
+++ b/monitor/qmp-cmds.c
@@ -133,8 +133,11 @@ void qmp_cont(Error **errp)
blk_iostatus_reset(blk);
}
- for (job = block_job_next(NULL); job; job = block_job_next(job)) {
- block_job_iostatus_reset(job);
+ WITH_JOB_LOCK_GUARD() {
+ for (job = block_job_next_locked(NULL); job;
+ job = block_job_next_locked(job)) {
+ block_job_iostatus_reset_locked(job);
+ }
}
/* Continuing after completed migration. Images have been inactivated to
diff --git a/qemu-img.c b/qemu-img.c
index 4cf4d2423d..289d88a156 100644
--- a/qemu-img.c
+++ b/qemu-img.c
@@ -912,25 +912,30 @@ static void run_block_job(BlockJob *job, Error **errp)
int ret = 0;
aio_context_acquire(aio_context);
- job_ref(&job->job);
- do {
- float progress = 0.0f;
- aio_poll(aio_context, true);
+ WITH_JOB_LOCK_GUARD() {
+ job_ref_locked(&job->job);
+ do {
+ float progress = 0.0f;
+ job_unlock();
+ aio_poll(aio_context, true);
+
+ progress_get_snapshot(&job->job.progress, &progress_current,
+ &progress_total);
+ if (progress_total) {
+ progress = (float)progress_current / progress_total * 100.f;
+ }
+ qemu_progress_print(progress, 0);
+ job_lock();
+ } while (!job_is_ready_locked(&job->job) &&
+ !job_is_completed_locked(&job->job));
- progress_get_snapshot(&job->job.progress, &progress_current,
- &progress_total);
- if (progress_total) {
- progress = (float)progress_current / progress_total * 100.f;
+ if (!job_is_completed_locked(&job->job)) {
+ ret = job_complete_sync_locked(&job->job, errp);
+ } else {
+ ret = job->job.ret;
}
- qemu_progress_print(progress, 0);
- } while (!job_is_ready(&job->job) && !job_is_completed(&job->job));
-
- if (!job_is_completed(&job->job)) {
- ret = job_complete_sync(&job->job, errp);
- } else {
- ret = job->job.ret;
+ job_unref_locked(&job->job);
}
- job_unref(&job->job);
aio_context_release(aio_context);
/* publish completion progress only when success */
@@ -1083,7 +1088,9 @@ static int img_commit(int argc, char **argv)
bdrv_ref(bs);
}
- job = block_job_get("commit");
+ WITH_JOB_LOCK_GUARD() {
+ job = block_job_get_locked("commit");
+ }
assert(job);
run_block_job(job, &local_err);
if (local_err) {
--
2.31.1On 7/6/22 23:15, Emanuele Giuseppe Esposito wrote:
> Now that the API offers also _locked() functions, take advantage
> of it and give also the caller control to take the lock and call
> _locked functions.
>
> This makes sense especially when we have for loops, because it
> makes no sense to have:
>
> for(job = job_next(); ...)
>
> where each job_next() takes the lock internally.
> Instead we want
>
> JOB_LOCK_GUARD();
> for(job = job_next_locked(); ...)
>
> Note: at this stage, job_{lock/unlock} and job lock guard macros
> are *nop*.
>
> Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
> ---
[..]
>
> diff --git a/blockjob.c b/blockjob.c
> index 0d59aba439..bce05a9096 100644
> --- a/blockjob.c
> +++ b/blockjob.c
> @@ -99,7 +99,9 @@ static char *child_job_get_parent_desc(BdrvChild *c)
> static void child_job_drained_begin(BdrvChild *c)
> {
> BlockJob *job = c->opaque;
> - job_pause(&job->job);
> + WITH_JOB_LOCK_GUARD() {
> + job_pause_locked(&job->job);
> + }
What's the reason for it? I'd keep job_pause().
(and it doesn't correspond to what commit subject presents.)
> }
>
> static bool child_job_drained_poll(BdrvChild *c)
> @@ -111,8 +113,10 @@ static bool child_job_drained_poll(BdrvChild *c)
> /* An inactive or completed job doesn't have any pending requests. Jobs
> * with !job->busy are either already paused or have a pause point after
> * being reentered, so no job driver code will run before they pause. */
> - if (!job->busy || job_is_completed(job)) {
> - return false;
> + WITH_JOB_LOCK_GUARD() {
> + if (!job->busy || job_is_completed_locked(job)) {
> + return false;
> + }
> }
This doesn't correspond to commit subject. I'd put such things to separate commit "correct use of job_mutex in blockjob.c".
>
> /* Otherwise, assume that it isn't fully stopped yet, but allow the job to
> @@ -127,7 +131,9 @@ static bool child_job_drained_poll(BdrvChild *c)
> static void child_job_drained_end(BdrvChild *c, int *drained_end_counter)
> {
> BlockJob *job = c->opaque;
> - job_resume(&job->job);
> + WITH_JOB_LOCK_GUARD() {
> + job_resume_locked(&job->job);
> + }
> }
Again, don't see a reason for such change.
[my comments relate to more similar cases in the patch]
--
Best regards,
Vladimir
Am 11/07/2022 um 15:26 schrieb Vladimir Sementsov-Ogievskiy:
>> }
>> static bool child_job_drained_poll(BdrvChild *c)
>> @@ -111,8 +113,10 @@ static bool child_job_drained_poll(BdrvChild *c)
>> /* An inactive or completed job doesn't have any pending
>> requests. Jobs
>> * with !job->busy are either already paused or have a pause
>> point after
>> * being reentered, so no job driver code will run before they
>> pause. */
>> - if (!job->busy || job_is_completed(job)) {
>> - return false;
>> + WITH_JOB_LOCK_GUARD() {
>> + if (!job->busy || job_is_completed_locked(job)) {
>> + return false;
>> + }
>> }
>
> This doesn't correspond to commit subject. I'd put such things to
> separate commit "correct use of job_mutex in blockjob.c".
>
>> /* Otherwise, assume that it isn't fully stopped yet, but
>> allow the job to
>> @@ -127,7 +131,9 @@ static bool child_job_drained_poll(BdrvChild *c)
>> static void child_job_drained_end(BdrvChild *c, int
>> *drained_end_counter)
>> {
>> BlockJob *job = c->opaque;
>> - job_resume(&job->job);
>> + WITH_JOB_LOCK_GUARD() {
>> + job_resume_locked(&job->job);
>> + }
>> }
>
> Again, don't see a reason for such change.
>
>
> [my comments relate to more similar cases in the patch]
I think you misunderstood: I aim to group API calls under the same lock.
One application of such grouping involves loops, but not only them.
Regarding the single-line WITH_JOB_LOCK_GUARD (job_next, job_pause,
job_resume and similar), I guess I will keep the not-locked function.
Emanuele
On 7/19/22 15:40, Emanuele Giuseppe Esposito wrote:
>
>
> Am 11/07/2022 um 15:26 schrieb Vladimir Sementsov-Ogievskiy:
>>> }
>>> static bool child_job_drained_poll(BdrvChild *c)
>>> @@ -111,8 +113,10 @@ static bool child_job_drained_poll(BdrvChild *c)
>>> /* An inactive or completed job doesn't have any pending
>>> requests. Jobs
>>> * with !job->busy are either already paused or have a pause
>>> point after
>>> * being reentered, so no job driver code will run before they
>>> pause. */
>>> - if (!job->busy || job_is_completed(job)) {
>>> - return false;
>>> + WITH_JOB_LOCK_GUARD() {
>>> + if (!job->busy || job_is_completed_locked(job)) {
>>> + return false;
>>> + }
>>> }
>>
>> This doesn't correspond to commit subject. I'd put such things to
>> separate commit "correct use of job_mutex in blockjob.c".
>>
>>> /* Otherwise, assume that it isn't fully stopped yet, but
>>> allow the job to
>>> @@ -127,7 +131,9 @@ static bool child_job_drained_poll(BdrvChild *c)
>>> static void child_job_drained_end(BdrvChild *c, int
>>> *drained_end_counter)
>>> {
>>> BlockJob *job = c->opaque;
>>> - job_resume(&job->job);
>>> + WITH_JOB_LOCK_GUARD() {
>>> + job_resume_locked(&job->job);
>>> + }
>>> }
>>
>> Again, don't see a reason for such change.
>>
>>
>> [my comments relate to more similar cases in the patch]
>
> I think you misunderstood: I aim to group API calls under the same lock.
> One application of such grouping involves loops, but not only them.
I mean that pre-patch job->busy is accessed without any lock at all. So we not just group correctly locked calls into one critical section, we also fix direct field accesses to be under lock.
>
> Regarding the single-line WITH_JOB_LOCK_GUARD (job_next, job_pause,
> job_resume and similar), I guess I will keep the not-locked function.
>
> Emanuele
>
--
Best regards,
Vladimir
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