From 6e9a5d0ef7ada1b153e0808c0fe73eeab940cfbd Mon Sep 17 00:00:00 2001

From: Kevin Wolf <kwolf@redhat.com>

Date: Tue, 26 Jun 2018 09:48:11 +0200

Subject: [PATCH 42/89] job: Move pause/resume functions to Job

RH-Author: Kevin Wolf <kwolf@redhat.com>

Message-id: <20180626094856.6924-29-kwolf@redhat.com>

Patchwork-id: 81062

O-Subject: [RHV-7.6 qemu-kvm-rhev PATCH v2 28/73] job: Move pause/resume functions to Job

Bugzilla: 1513543

RH-Acked-by: Jeffrey Cody <jcody@redhat.com>

RH-Acked-by: Max Reitz <mreitz@redhat.com>

RH-Acked-by: Fam Zheng <famz@redhat.com>

While we already moved the state related to job pausing to Job, the

functions to do were still BlockJob only. This commit moves them over to

Job.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>

Reviewed-by: Max Reitz <mreitz@redhat.com>

Reviewed-by: John Snow <jsnow@redhat.com>

(cherry picked from commit b15de82867975e0b4acf644b5ee36d84904b6612)

Signed-off-by: Kevin Wolf <kwolf@redhat.com>

Signed-off-by: Miroslav Rezanina <mrezanin@redhat.com>

---

 block/backup.c               |  1 +

 block/commit.c               |  1 +

 block/mirror.c               |  2 ++

 block/stream.c               |  1 +

 blockdev.c                   |  6 ++--

 blockjob.c                   | 81 +++++++++-----------------------------------

 include/block/blockjob.h     | 32 -----------------

 include/block/blockjob_int.h |  7 ++++

 include/qemu/job.h           | 37 ++++++++++++++++++++

 job.c                        | 59 ++++++++++++++++++++++++++++++++

 tests/test-bdrv-drain.c      |  1 +

 tests/test-blockjob-txn.c    |  1 +

 tests/test-blockjob.c        |  6 ++--

 13 files changed, 133 insertions(+), 102 deletions(-)

diff --git a/block/backup.c b/block/backup.c

index f3a4f7c..4d011d5 100644

--- a/block/backup.c

+++ b/block/backup.c

@@ -528,6 +528,7 @@ static const BlockJobDriver backup_job_driver = {

         .instance_size          = sizeof(BackupBlockJob),

         .job_type               = JOB_TYPE_BACKUP,

         .free                   = block_job_free,

+        .user_resume            = block_job_user_resume,

         .start                  = backup_run,

     },

     .commit                 = backup_commit,

diff --git a/block/commit.c b/block/commit.c

index 1c6cb6c..c4a98e5 100644

--- a/block/commit.c

+++ b/block/commit.c

@@ -220,6 +220,7 @@ static const BlockJobDriver commit_job_driver = {

         .instance_size = sizeof(CommitBlockJob),

         .job_type      = JOB_TYPE_COMMIT,

         .free          = block_job_free,

+        .user_resume   = block_job_user_resume,

         .start         = commit_run,

     },

 };

diff --git a/block/mirror.c b/block/mirror.c

index 5d8f75c..9a7226f 100644

--- a/block/mirror.c

+++ b/block/mirror.c

@@ -991,6 +991,7 @@ static const BlockJobDriver mirror_job_driver = {

         .instance_size          = sizeof(MirrorBlockJob),

         .job_type               = JOB_TYPE_MIRROR,

         .free                   = block_job_free,

+        .user_resume            = block_job_user_resume,

         .start                  = mirror_run,

         .pause                  = mirror_pause,

     },

@@ -1004,6 +1005,7 @@ static const BlockJobDriver commit_active_job_driver = {

         .instance_size          = sizeof(MirrorBlockJob),

         .job_type               = JOB_TYPE_COMMIT,

         .free                   = block_job_free,

+        .user_resume            = block_job_user_resume,

         .start                  = mirror_run,

         .pause                  = mirror_pause,

     },

diff --git a/block/stream.c b/block/stream.c

index 1faab02..e81b488 100644

--- a/block/stream.c

+++ b/block/stream.c

@@ -214,6 +214,7 @@ static const BlockJobDriver stream_job_driver = {

         .job_type      = JOB_TYPE_STREAM,

         .free          = block_job_free,

         .start         = stream_run,

+        .user_resume   = block_job_user_resume,

     },

 };

diff --git a/blockdev.c b/blockdev.c

index efb83c4..0fa1990 100644

--- a/blockdev.c

+++ b/blockdev.c

@@ -3891,7 +3891,7 @@ void qmp_block_job_cancel(const char *device,

         force = false;

     }

-    if (block_job_user_paused(job) && !force) {

+    if (job_user_paused(&job->job) && !force) {

         error_setg(errp, "The block job for device '%s' is currently paused",

                    device);

         goto out;

@@ -3913,7 +3913,7 @@ void qmp_block_job_pause(const char *device, Error **errp)

     }

     trace_qmp_block_job_pause(job);

-    block_job_user_pause(job, errp);

+    job_user_pause(&job->job, errp);

     aio_context_release(aio_context);

 }

@@ -3927,7 +3927,7 @@ void qmp_block_job_resume(const char *device, Error **errp)

     }

     trace_qmp_block_job_resume(job);

-    block_job_user_resume(job, errp);

+    job_user_resume(&job->job, errp);

     aio_context_release(aio_context);

 }

diff --git a/blockjob.c b/blockjob.c

index 4dc360c..6334a54 100644

--- a/blockjob.c

+++ b/blockjob.c

@@ -140,29 +140,6 @@ static void block_job_txn_del_job(BlockJob *job)

     }

 }

-/* Assumes the job_mutex is held */

-static bool job_timer_not_pending(Job *job)

-{

-    return !timer_pending(&job->sleep_timer);

-}

-

-static void block_job_pause(BlockJob *job)

-{

-    job->job.pause_count++;

-}

-

-static void block_job_resume(BlockJob *job)

-{

-    assert(job->job.pause_count > 0);

-    job->job.pause_count--;

-    if (job->job.pause_count) {

-        return;

-    }

-

-    /* kick only if no timer is pending */

-    job_enter_cond(&job->job, job_timer_not_pending);

-}

-

 static void block_job_attached_aio_context(AioContext *new_context,

                                            void *opaque);

 static void block_job_detach_aio_context(void *opaque);

@@ -193,7 +170,7 @@ static void block_job_attached_aio_context(AioContext *new_context,

         job->driver->attached_aio_context(job, new_context);

     }

-    block_job_resume(job);

+    job_resume(&job->job);

 }

 static void block_job_drain(BlockJob *job)

@@ -214,7 +191,7 @@ static void block_job_detach_aio_context(void *opaque)

     /* In case the job terminates during aio_poll()... */

     job_ref(&job->job);

-    block_job_pause(job);

+    job_pause(&job->job);

     while (!job->job.paused && !job->completed) {

         block_job_drain(job);

@@ -233,13 +210,13 @@ static char *child_job_get_parent_desc(BdrvChild *c)

 static void child_job_drained_begin(BdrvChild *c)

 {

     BlockJob *job = c->opaque;

-    block_job_pause(job);

+    job_pause(&job->job);

 }

 static void child_job_drained_end(BdrvChild *c)

 {

     BlockJob *job = c->opaque;

-    block_job_resume(job);

+    job_resume(&job->job);

 }

 static const BdrvChildRole child_job = {

@@ -396,9 +373,9 @@ static void block_job_cancel_async(BlockJob *job, bool force)

     if (job->iostatus != BLOCK_DEVICE_IO_STATUS_OK) {

         block_job_iostatus_reset(job);

     }

-    if (job->user_paused) {

+    if (job->job.user_paused) {

         /* Do not call block_job_enter here, the caller will handle it.  */

-        job->user_paused = false;

+        job->job.user_paused = false;

         job->job.pause_count--;

     }

     job->job.cancelled = true;

@@ -628,39 +605,6 @@ void block_job_dismiss(BlockJob **jobptr, Error **errp)

     *jobptr = NULL;

 }

-void block_job_user_pause(BlockJob *job, Error **errp)

-{

-    if (job_apply_verb(&job->job, JOB_VERB_PAUSE, errp)) {

-        return;

-    }

-    if (job->user_paused) {

-        error_setg(errp, "Job is already paused");

-        return;

-    }

-    job->user_paused = true;

-    block_job_pause(job);

-}

-

-bool block_job_user_paused(BlockJob *job)

-{

-    return job->user_paused;

-}

-

-void block_job_user_resume(BlockJob *job, Error **errp)

-{

-    assert(job);

-    if (!job->user_paused || job->job.pause_count <= 0) {

-        error_setg(errp, "Can't resume a job that was not paused");

-        return;

-    }

-    if (job_apply_verb(&job->job, JOB_VERB_RESUME, errp)) {

-        return;

-    }

-    block_job_iostatus_reset(job);

-    job->user_paused = false;

-    block_job_resume(job);

-}

-

 void block_job_cancel(BlockJob *job, bool force)

 {

     if (job->job.status == JOB_STATUS_CONCLUDED) {

@@ -851,6 +795,7 @@ void *block_job_create(const char *job_id, const BlockJobDriver *driver,

     assert(is_block_job(&job->job));

     assert(job->job.driver->free == &block_job_free);

+    assert(job->job.driver->user_resume == &block_job_user_resume);

     job->driver        = driver;

     job->blk           = blk;

@@ -941,10 +886,16 @@ void block_job_iostatus_reset(BlockJob *job)

     if (job->iostatus == BLOCK_DEVICE_IO_STATUS_OK) {

         return;

     }

-    assert(job->user_paused && job->job.pause_count > 0);

+    assert(job->job.user_paused && job->job.pause_count > 0);

     job->iostatus = BLOCK_DEVICE_IO_STATUS_OK;

 }

+void block_job_user_resume(Job *job)

+{

+    BlockJob *bjob = container_of(job, BlockJob, job);

+    block_job_iostatus_reset(bjob);

+}

+

 void block_job_event_ready(BlockJob *job)

 {

     job_state_transition(&job->job, JOB_STATUS_READY);

@@ -991,9 +942,9 @@ BlockErrorAction block_job_error_action(BlockJob *job, BlockdevOnError on_err,

                                         action, &error_abort);

     }

     if (action == BLOCK_ERROR_ACTION_STOP) {

-        block_job_pause(job);

+        job_pause(&job->job);

         /* make the pause user visible, which will be resumed from QMP. */

-        job->user_paused = true;

+        job->job.user_paused = true;

         block_job_iostatus_set_err(job, error);

     }

     return action;

diff --git a/include/block/blockjob.h b/include/block/blockjob.h

index b60d919..556a8f6 100644

--- a/include/block/blockjob.h

+++ b/include/block/blockjob.h

@@ -57,12 +57,6 @@ typedef struct BlockJob {

     bool force;

     /**

-     * Set to true if the job is paused by user.  Can be unpaused with the

-     * block-job-resume QMP command.

-     */

-    bool user_paused;

-

-    /**

      * Set to true when the job is ready to be completed.

      */

     bool ready;

@@ -248,32 +242,6 @@ void block_job_progress_set_remaining(BlockJob *job, uint64_t remaining);

 BlockJobInfo *block_job_query(BlockJob *job, Error **errp);

 /**

- * block_job_user_pause:

- * @job: The job to be paused.

- *

- * Asynchronously pause the specified job.

- * Do not allow a resume until a matching call to block_job_user_resume.

- */

-void block_job_user_pause(BlockJob *job, Error **errp);

-

-/**

- * block_job_paused:

- * @job: The job to query.

- *

- * Returns true if the job is user-paused.

- */

-bool block_job_user_paused(BlockJob *job);

-

-/**

- * block_job_user_resume:

- * @job: The job to be resumed.

- *

- * Resume the specified job.

- * Must be paired with a preceding block_job_user_pause.

- */

-void block_job_user_resume(BlockJob *job, Error **errp);

-

-/**

  * block_job_user_cancel:

  * @job: The job to be cancelled.

  * @force: Quit a job without waiting for data to be in sync.

diff --git a/include/block/blockjob_int.h b/include/block/blockjob_int.h

index 8937f5b..7e705ae 100644

--- a/include/block/blockjob_int.h

+++ b/include/block/blockjob_int.h

@@ -134,6 +134,13 @@ void *block_job_create(const char *job_id, const BlockJobDriver *driver,

 void block_job_free(Job *job);

 /**

+ * block_job_user_resume:

+ * Callback to be used for JobDriver.user_resume in all block jobs. Resets the

+ * iostatus when the user resumes @job.

+ */

+void block_job_user_resume(Job *job);

+

+/**

  * block_job_yield:

  * @job: The job that calls the function.

  *

diff --git a/include/qemu/job.h b/include/qemu/job.h

index 509408f..bc63985 100644

--- a/include/qemu/job.h

+++ b/include/qemu/job.h

@@ -83,6 +83,12 @@ typedef struct Job {

     bool paused;

     /**

+     * Set to true if the job is paused by user.  Can be unpaused with the

+     * block-job-resume QMP command.

+     */

+    bool user_paused;

+

+    /**

      * Set to true if the job should cancel itself.  The flag must

      * always be tested just before toggling the busy flag from false

      * to true.  After a job has been cancelled, it should only yield

@@ -124,6 +130,12 @@ struct JobDriver {

      */

     void coroutine_fn (*resume)(Job *job);

+    /**

+     * Called when the job is resumed by the user (i.e. user_paused becomes

+     * false). .user_resume is called before .resume.

+     */

+    void (*user_resume)(Job *job);

+

     /** Called when the job is freed */

     void (*free)(Job *job);

 };

@@ -203,6 +215,31 @@ const char *job_type_str(const Job *job);

 bool job_is_cancelled(Job *job);

 /**

+ * Request @job to pause at the next pause point. Must be paired with

+ * job_resume(). If the job is supposed to be resumed by user action, call

+ * job_user_pause() instead.

+ */

+void job_pause(Job *job);

+

+/** Resumes a @job paused with job_pause. */

+void job_resume(Job *job);

+

+/**

+ * Asynchronously pause the specified @job.

+ * Do not allow a resume until a matching call to job_user_resume.

+ */

+void job_user_pause(Job *job, Error **errp);

+

+/** Returns true if the job is user-paused. */

+bool job_user_paused(Job *job);

+

+/**

+ * Resume the specified @job.

+ * Must be paired with a preceding job_user_pause.

+ */

+void job_user_resume(Job *job, Error **errp);

+

+/**

  * Get the next element from the list of block jobs after @job, or the

  * first one if @job is %NULL.

  *

diff --git a/job.c b/job.c

index 1b8cba1..fd10b1d 100644

--- a/job.c

+++ b/job.c

@@ -341,6 +341,65 @@ void job_start(Job *job)

     aio_co_enter(job->aio_context, job->co);

 }

+/* Assumes the block_job_mutex is held */

+static bool job_timer_not_pending(Job *job)

+{

+    return !timer_pending(&job->sleep_timer);

+}

+

+void job_pause(Job *job)

+{

+    job->pause_count++;

+}

+

+void job_resume(Job *job)

+{

+    assert(job->pause_count > 0);

+    job->pause_count--;

+    if (job->pause_count) {

+        return;

+    }

+

+    /* kick only if no timer is pending */

+    job_enter_cond(job, job_timer_not_pending);

+}

+

+void job_user_pause(Job *job, Error **errp)

+{

+    if (job_apply_verb(job, JOB_VERB_PAUSE, errp)) {

+        return;

+    }

+    if (job->user_paused) {

+        error_setg(errp, "Job is already paused");

+        return;

+    }

+    job->user_paused = true;

+    job_pause(job);

+}

+

+bool job_user_paused(Job *job)

+{

+    return job->user_paused;

+}

+

+void job_user_resume(Job *job, Error **errp)

+{

+    assert(job);

+    if (!job->user_paused || job->pause_count <= 0) {

+        error_setg(errp, "Can't resume a job that was not paused");

+        return;

+    }

+    if (job_apply_verb(job, JOB_VERB_RESUME, errp)) {

+        return;

+    }

+    if (job->driver->user_resume) {

+        job->driver->user_resume(job);

+    }

+    job->user_paused = false;

+    job_resume(job);

+}

+

+

 typedef struct {

     Job *job;

     JobDeferToMainLoopFn *fn;

diff --git a/tests/test-bdrv-drain.c b/tests/test-bdrv-drain.c

index 50232f5..c993512 100644

--- a/tests/test-bdrv-drain.c

+++ b/tests/test-bdrv-drain.c

@@ -524,6 +524,7 @@ BlockJobDriver test_job_driver = {

     .job_driver = {

         .instance_size  = sizeof(TestBlockJob),

         .free           = block_job_free,

+        .user_resume    = block_job_user_resume,

         .start          = test_job_start,

     },

     .complete       = test_job_complete,

diff --git a/tests/test-blockjob-txn.c b/tests/test-blockjob-txn.c

index 0e6162b..93d1ff0 100644

--- a/tests/test-blockjob-txn.c

+++ b/tests/test-blockjob-txn.c

@@ -78,6 +78,7 @@ static const BlockJobDriver test_block_job_driver = {

     .job_driver = {

         .instance_size = sizeof(TestBlockJob),

         .free          = block_job_free,

+        .user_resume   = block_job_user_resume,

         .start         = test_block_job_run,

     },

 };

diff --git a/tests/test-blockjob.c b/tests/test-blockjob.c

index b329bd5..ceb5960 100644

--- a/tests/test-blockjob.c

+++ b/tests/test-blockjob.c

@@ -20,6 +20,7 @@ static const BlockJobDriver test_block_job_driver = {

     .job_driver = {

         .instance_size = sizeof(BlockJob),

         .free          = block_job_free,

+        .user_resume   = block_job_user_resume,

     },

 };

@@ -199,6 +200,7 @@ static const BlockJobDriver test_cancel_driver = {

     .job_driver = {

         .instance_size = sizeof(CancelJob),

         .free          = block_job_free,

+        .user_resume   = block_job_user_resume,

         .start         = cancel_job_start,

     },

     .complete      = cancel_job_complete,

@@ -270,7 +272,7 @@ static void test_cancel_paused(void)

     job_start(&job->job);

     assert(job->job.status == JOB_STATUS_RUNNING);

-    block_job_user_pause(job, &error_abort);

+    job_user_pause(&job->job, &error_abort);

     block_job_enter(job);

     assert(job->job.status == JOB_STATUS_PAUSED);

@@ -308,7 +310,7 @@ static void test_cancel_standby(void)

     block_job_enter(job);

     assert(job->job.status == JOB_STATUS_READY);

-    block_job_user_pause(job, &error_abort);

+    job_user_pause(&job->job, &error_abort);

     block_job_enter(job);

     assert(job->job.status == JOB_STATUS_STANDBY);

-- 

1.8.3.1