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From: Kevin Wolf <kwolf@redhat.com>
To: qemu-block@nongnu.org
Cc: kwolf@redhat.com, stefanha@redhat.com, qemu-devel@nongnu.org
Subject: [PULL 37/50] jobs: use job locks also in the unit tests
Date: Fri,  7 Oct 2022 12:47:39 +0200	[thread overview]
Message-ID: <20221007104752.141361-38-kwolf@redhat.com> (raw)
In-Reply-To: <20221007104752.141361-1-kwolf@redhat.com>

From: Emanuele Giuseppe Esposito <eesposit@redhat.com>

Add missing job synchronization in the unit tests, with
explicit locks.

We are deliberately using _locked functions wrapped by a guard
instead of a normal call because the normal call will be removed
in future, as the only usage is limited to the tests.

In other words, if a function like job_pause() is/will be only used
in tests to avoid:

WITH_JOB_LOCK_GUARD(){
    job_pause_locked();
}

then it is not worth keeping job_pause(), and just use the guard.

Note: at this stage, job_{lock/unlock} and job lock guard macros
are *nop*.

Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20220926093214.506243-10-eesposit@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
---
 tests/unit/test-bdrv-drain.c     |  76 ++++++++++++--------
 tests/unit/test-block-iothread.c |   8 ++-
 tests/unit/test-blockjob-txn.c   |  24 ++++---
 tests/unit/test-blockjob.c       | 115 +++++++++++++++++++------------
 4 files changed, 140 insertions(+), 83 deletions(-)

diff --git a/tests/unit/test-bdrv-drain.c b/tests/unit/test-bdrv-drain.c
index 36be84ae55..0db056ea63 100644
--- a/tests/unit/test-bdrv-drain.c
+++ b/tests/unit/test-bdrv-drain.c
@@ -943,61 +943,83 @@ static void test_blockjob_common_drain_node(enum drain_type drain_type,
         }
     }
 
-    g_assert_cmpint(job->job.pause_count, ==, 0);
-    g_assert_false(job->job.paused);
-    g_assert_true(tjob->running);
-    g_assert_true(job->job.busy); /* We're in qemu_co_sleep_ns() */
+    WITH_JOB_LOCK_GUARD() {
+        g_assert_cmpint(job->job.pause_count, ==, 0);
+        g_assert_false(job->job.paused);
+        g_assert_true(tjob->running);
+        g_assert_true(job->job.busy); /* We're in qemu_co_sleep_ns() */
+    }
 
     do_drain_begin_unlocked(drain_type, drain_bs);
 
-    if (drain_type == BDRV_DRAIN_ALL) {
-        /* bdrv_drain_all() drains both src and target */
-        g_assert_cmpint(job->job.pause_count, ==, 2);
-    } else {
-        g_assert_cmpint(job->job.pause_count, ==, 1);
+    WITH_JOB_LOCK_GUARD() {
+        if (drain_type == BDRV_DRAIN_ALL) {
+            /* bdrv_drain_all() drains both src and target */
+            g_assert_cmpint(job->job.pause_count, ==, 2);
+        } else {
+            g_assert_cmpint(job->job.pause_count, ==, 1);
+        }
+        g_assert_true(job->job.paused);
+        g_assert_false(job->job.busy); /* The job is paused */
     }
-    g_assert_true(job->job.paused);
-    g_assert_false(job->job.busy); /* The job is paused */
 
     do_drain_end_unlocked(drain_type, drain_bs);
 
     if (use_iothread) {
-        /* paused is reset in the I/O thread, wait for it */
+        /*
+         * Here we are waiting for the paused status to change,
+         * so don't bother protecting the read every time.
+         *
+         * paused is reset in the I/O thread, wait for it
+         */
         while (job->job.paused) {
             aio_poll(qemu_get_aio_context(), false);
         }
     }
 
-    g_assert_cmpint(job->job.pause_count, ==, 0);
-    g_assert_false(job->job.paused);
-    g_assert_true(job->job.busy); /* We're in qemu_co_sleep_ns() */
+    WITH_JOB_LOCK_GUARD() {
+        g_assert_cmpint(job->job.pause_count, ==, 0);
+        g_assert_false(job->job.paused);
+        g_assert_true(job->job.busy); /* We're in qemu_co_sleep_ns() */
+    }
 
     do_drain_begin_unlocked(drain_type, target);
 
-    if (drain_type == BDRV_DRAIN_ALL) {
-        /* bdrv_drain_all() drains both src and target */
-        g_assert_cmpint(job->job.pause_count, ==, 2);
-    } else {
-        g_assert_cmpint(job->job.pause_count, ==, 1);
+    WITH_JOB_LOCK_GUARD() {
+        if (drain_type == BDRV_DRAIN_ALL) {
+            /* bdrv_drain_all() drains both src and target */
+            g_assert_cmpint(job->job.pause_count, ==, 2);
+        } else {
+            g_assert_cmpint(job->job.pause_count, ==, 1);
+        }
+        g_assert_true(job->job.paused);
+        g_assert_false(job->job.busy); /* The job is paused */
     }
-    g_assert_true(job->job.paused);
-    g_assert_false(job->job.busy); /* The job is paused */
 
     do_drain_end_unlocked(drain_type, target);
 
     if (use_iothread) {
-        /* paused is reset in the I/O thread, wait for it */
+        /*
+         * Here we are waiting for the paused status to change,
+         * so don't bother protecting the read every time.
+         *
+         * paused is reset in the I/O thread, wait for it
+         */
         while (job->job.paused) {
             aio_poll(qemu_get_aio_context(), false);
         }
     }
 
-    g_assert_cmpint(job->job.pause_count, ==, 0);
-    g_assert_false(job->job.paused);
-    g_assert_true(job->job.busy); /* We're in qemu_co_sleep_ns() */
+    WITH_JOB_LOCK_GUARD() {
+        g_assert_cmpint(job->job.pause_count, ==, 0);
+        g_assert_false(job->job.paused);
+        g_assert_true(job->job.busy); /* We're in qemu_co_sleep_ns() */
+    }
 
     aio_context_acquire(ctx);
-    ret = job_complete_sync(&job->job, &error_abort);
+    WITH_JOB_LOCK_GUARD() {
+        ret = job_complete_sync_locked(&job->job, &error_abort);
+    }
     g_assert_cmpint(ret, ==, (result == TEST_JOB_SUCCESS ? 0 : -EIO));
 
     if (use_iothread) {
diff --git a/tests/unit/test-block-iothread.c b/tests/unit/test-block-iothread.c
index 8b55eccc89..96fd21c00a 100644
--- a/tests/unit/test-block-iothread.c
+++ b/tests/unit/test-block-iothread.c
@@ -583,7 +583,9 @@ static void test_attach_blockjob(void)
     }
 
     aio_context_acquire(ctx);
-    job_complete_sync(&tjob->common.job, &error_abort);
+    WITH_JOB_LOCK_GUARD() {
+        job_complete_sync_locked(&tjob->common.job, &error_abort);
+    }
     blk_set_aio_context(blk, qemu_get_aio_context(), &error_abort);
     aio_context_release(ctx);
 
@@ -757,7 +759,9 @@ static void test_propagate_mirror(void)
                  BLOCKDEV_ON_ERROR_REPORT, BLOCKDEV_ON_ERROR_REPORT,
                  false, "filter_node", MIRROR_COPY_MODE_BACKGROUND,
                  &error_abort);
-    job = job_get("job0");
+    WITH_JOB_LOCK_GUARD() {
+        job = job_get_locked("job0");
+    }
     filter = bdrv_find_node("filter_node");
 
     /* Change the AioContext of src */
diff --git a/tests/unit/test-blockjob-txn.c b/tests/unit/test-blockjob-txn.c
index c69028b450..d3b0bb24be 100644
--- a/tests/unit/test-blockjob-txn.c
+++ b/tests/unit/test-blockjob-txn.c
@@ -116,8 +116,10 @@ static void test_single_job(int expected)
     job = test_block_job_start(1, true, expected, &result, txn);
     job_start(&job->job);
 
-    if (expected == -ECANCELED) {
-        job_cancel(&job->job, false);
+    WITH_JOB_LOCK_GUARD() {
+        if (expected == -ECANCELED) {
+            job_cancel_locked(&job->job, false);
+        }
     }
 
     while (result == -EINPROGRESS) {
@@ -160,13 +162,15 @@ static void test_pair_jobs(int expected1, int expected2)
     /* Release our reference now to trigger as many nice
      * use-after-free bugs as possible.
      */
-    job_txn_unref(txn);
+    WITH_JOB_LOCK_GUARD() {
+        job_txn_unref_locked(txn);
 
-    if (expected1 == -ECANCELED) {
-        job_cancel(&job1->job, false);
-    }
-    if (expected2 == -ECANCELED) {
-        job_cancel(&job2->job, false);
+        if (expected1 == -ECANCELED) {
+            job_cancel_locked(&job1->job, false);
+        }
+        if (expected2 == -ECANCELED) {
+            job_cancel_locked(&job2->job, false);
+        }
     }
 
     while (result1 == -EINPROGRESS || result2 == -EINPROGRESS) {
@@ -219,7 +223,9 @@ static void test_pair_jobs_fail_cancel_race(void)
     job_start(&job1->job);
     job_start(&job2->job);
 
-    job_cancel(&job1->job, false);
+    WITH_JOB_LOCK_GUARD() {
+        job_cancel_locked(&job1->job, false);
+    }
 
     /* Now make job2 finish before the main loop kicks jobs.  This simulates
      * the race between a pending kick and another job completing.
diff --git a/tests/unit/test-blockjob.c b/tests/unit/test-blockjob.c
index 4c9e1bf1e5..e4f126bb6d 100644
--- a/tests/unit/test-blockjob.c
+++ b/tests/unit/test-blockjob.c
@@ -211,8 +211,11 @@ static CancelJob *create_common(Job **pjob)
     bjob = mk_job(blk, "Steve", &test_cancel_driver, true,
                   JOB_MANUAL_FINALIZE | JOB_MANUAL_DISMISS);
     job = &bjob->job;
-    job_ref(job);
-    assert(job->status == JOB_STATUS_CREATED);
+    WITH_JOB_LOCK_GUARD() {
+        job_ref_locked(job);
+        assert(job->status == JOB_STATUS_CREATED);
+    }
+
     s = container_of(bjob, CancelJob, common);
     s->blk = blk;
 
@@ -231,12 +234,14 @@ static void cancel_common(CancelJob *s)
     aio_context_acquire(ctx);
 
     job_cancel_sync(&job->job, true);
-    if (sts != JOB_STATUS_CREATED && sts != JOB_STATUS_CONCLUDED) {
-        Job *dummy = &job->job;
-        job_dismiss(&dummy, &error_abort);
+    WITH_JOB_LOCK_GUARD() {
+        if (sts != JOB_STATUS_CREATED && sts != JOB_STATUS_CONCLUDED) {
+            Job *dummy = &job->job;
+            job_dismiss_locked(&dummy, &error_abort);
+        }
+        assert(job->job.status == JOB_STATUS_NULL);
+        job_unref_locked(&job->job);
     }
-    assert(job->job.status == JOB_STATUS_NULL);
-    job_unref(&job->job);
     destroy_blk(blk);
 
     aio_context_release(ctx);
@@ -251,6 +256,13 @@ static void test_cancel_created(void)
     cancel_common(s);
 }
 
+static void assert_job_status_is(Job *job, int status)
+{
+    WITH_JOB_LOCK_GUARD() {
+        assert(job->status == status);
+    }
+}
+
 static void test_cancel_running(void)
 {
     Job *job;
@@ -259,7 +271,7 @@ static void test_cancel_running(void)
     s = create_common(&job);
 
     job_start(job);
-    assert(job->status == JOB_STATUS_RUNNING);
+    assert_job_status_is(job, JOB_STATUS_RUNNING);
 
     cancel_common(s);
 }
@@ -272,11 +284,12 @@ static void test_cancel_paused(void)
     s = create_common(&job);
 
     job_start(job);
-    assert(job->status == JOB_STATUS_RUNNING);
-
-    job_user_pause(job, &error_abort);
+    WITH_JOB_LOCK_GUARD() {
+        assert(job->status == JOB_STATUS_RUNNING);
+        job_user_pause_locked(job, &error_abort);
+    }
     job_enter(job);
-    assert(job->status == JOB_STATUS_PAUSED);
+    assert_job_status_is(job, JOB_STATUS_PAUSED);
 
     cancel_common(s);
 }
@@ -289,11 +302,11 @@ static void test_cancel_ready(void)
     s = create_common(&job);
 
     job_start(job);
-    assert(job->status == JOB_STATUS_RUNNING);
+    assert_job_status_is(job, JOB_STATUS_RUNNING);
 
     s->should_converge = true;
     job_enter(job);
-    assert(job->status == JOB_STATUS_READY);
+    assert_job_status_is(job, JOB_STATUS_READY);
 
     cancel_common(s);
 }
@@ -306,15 +319,16 @@ static void test_cancel_standby(void)
     s = create_common(&job);
 
     job_start(job);
-    assert(job->status == JOB_STATUS_RUNNING);
+    assert_job_status_is(job, JOB_STATUS_RUNNING);
 
     s->should_converge = true;
     job_enter(job);
-    assert(job->status == JOB_STATUS_READY);
-
-    job_user_pause(job, &error_abort);
+    WITH_JOB_LOCK_GUARD() {
+        assert(job->status == JOB_STATUS_READY);
+        job_user_pause_locked(job, &error_abort);
+    }
     job_enter(job);
-    assert(job->status == JOB_STATUS_STANDBY);
+    assert_job_status_is(job, JOB_STATUS_STANDBY);
 
     cancel_common(s);
 }
@@ -327,20 +341,21 @@ static void test_cancel_pending(void)
     s = create_common(&job);
 
     job_start(job);
-    assert(job->status == JOB_STATUS_RUNNING);
+    assert_job_status_is(job, JOB_STATUS_RUNNING);
 
     s->should_converge = true;
     job_enter(job);
-    assert(job->status == JOB_STATUS_READY);
-
-    job_complete(job, &error_abort);
+    WITH_JOB_LOCK_GUARD() {
+        assert(job->status == JOB_STATUS_READY);
+        job_complete_locked(job, &error_abort);
+    }
     job_enter(job);
     while (!job->deferred_to_main_loop) {
         aio_poll(qemu_get_aio_context(), true);
     }
-    assert(job->status == JOB_STATUS_READY);
+    assert_job_status_is(job, JOB_STATUS_READY);
     aio_poll(qemu_get_aio_context(), true);
-    assert(job->status == JOB_STATUS_PENDING);
+    assert_job_status_is(job, JOB_STATUS_PENDING);
 
     cancel_common(s);
 }
@@ -353,25 +368,28 @@ static void test_cancel_concluded(void)
     s = create_common(&job);
 
     job_start(job);
-    assert(job->status == JOB_STATUS_RUNNING);
+    assert_job_status_is(job, JOB_STATUS_RUNNING);
 
     s->should_converge = true;
     job_enter(job);
-    assert(job->status == JOB_STATUS_READY);
-
-    job_complete(job, &error_abort);
+    WITH_JOB_LOCK_GUARD() {
+        assert(job->status == JOB_STATUS_READY);
+        job_complete_locked(job, &error_abort);
+    }
     job_enter(job);
     while (!job->deferred_to_main_loop) {
         aio_poll(qemu_get_aio_context(), true);
     }
-    assert(job->status == JOB_STATUS_READY);
+    assert_job_status_is(job, JOB_STATUS_READY);
     aio_poll(qemu_get_aio_context(), true);
-    assert(job->status == JOB_STATUS_PENDING);
+    assert_job_status_is(job, JOB_STATUS_PENDING);
 
     aio_context_acquire(job->aio_context);
-    job_finalize(job, &error_abort);
+    WITH_JOB_LOCK_GUARD() {
+        job_finalize_locked(job, &error_abort);
+    }
     aio_context_release(job->aio_context);
-    assert(job->status == JOB_STATUS_CONCLUDED);
+    assert_job_status_is(job, JOB_STATUS_CONCLUDED);
 
     cancel_common(s);
 }
@@ -459,36 +477,43 @@ static void test_complete_in_standby(void)
     bjob = mk_job(blk, "job", &test_yielding_driver, true,
                   JOB_MANUAL_FINALIZE | JOB_MANUAL_DISMISS);
     job = &bjob->job;
-    assert(job->status == JOB_STATUS_CREATED);
+    assert_job_status_is(job, JOB_STATUS_CREATED);
 
     /* Wait for the job to become READY */
     job_start(job);
     aio_context_acquire(ctx);
+    /*
+     * Here we are waiting for the status to change, so don't bother
+     * protecting the read every time.
+     */
     AIO_WAIT_WHILE(ctx, job->status != JOB_STATUS_READY);
     aio_context_release(ctx);
 
     /* Begin the drained section, pausing the job */
     bdrv_drain_all_begin();
-    assert(job->status == JOB_STATUS_STANDBY);
+    assert_job_status_is(job, JOB_STATUS_STANDBY);
+
     /* Lock the IO thread to prevent the job from being run */
     aio_context_acquire(ctx);
     /* This will schedule the job to resume it */
     bdrv_drain_all_end();
 
-    /* But the job cannot run, so it will remain on standby */
-    assert(job->status == JOB_STATUS_STANDBY);
+    WITH_JOB_LOCK_GUARD() {
+        /* But the job cannot run, so it will remain on standby */
+        assert(job->status == JOB_STATUS_STANDBY);
 
-    /* Even though the job is on standby, this should work */
-    job_complete(job, &error_abort);
+        /* Even though the job is on standby, this should work */
+        job_complete_locked(job, &error_abort);
 
-    /* The test is done now, clean up. */
-    job_finish_sync(job, NULL, &error_abort);
-    assert(job->status == JOB_STATUS_PENDING);
+        /* The test is done now, clean up. */
+        job_finish_sync_locked(job, NULL, &error_abort);
+        assert(job->status == JOB_STATUS_PENDING);
 
-    job_finalize(job, &error_abort);
-    assert(job->status == JOB_STATUS_CONCLUDED);
+        job_finalize_locked(job, &error_abort);
+        assert(job->status == JOB_STATUS_CONCLUDED);
 
-    job_dismiss(&job, &error_abort);
+        job_dismiss_locked(&job, &error_abort);
+    }
 
     destroy_blk(blk);
     aio_context_release(ctx);
-- 
2.37.3



  parent reply	other threads:[~2022-10-07 13:02 UTC|newest]

Thread overview: 52+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-10-07 10:47 [PULL 00/50] Block layer patches Kevin Wolf
2022-10-07 10:47 ` [PULL 01/50] Revert "qapi: fix examples of blockdev-add with qcow2" Kevin Wolf
2022-10-07 10:47 ` [PULL 02/50] coroutine: Drop coroutine_fn annotation from qemu_coroutine_self() Kevin Wolf
2022-10-07 10:47 ` [PULL 03/50] block/nvme: separate nvme_get_free_req cases for coroutine/non-coroutine context Kevin Wolf
2022-10-07 10:47 ` [PULL 04/50] block: add missing coroutine_fn annotations Kevin Wolf
2022-10-07 10:47 ` [PULL 05/50] qcow2: remove incorrect " Kevin Wolf
2022-10-07 10:47 ` [PULL 06/50] nbd: " Kevin Wolf
2022-10-07 10:47 ` [PULL 07/50] coroutine: " Kevin Wolf
2022-10-07 10:47 ` [PULL 08/50] blkverify: add missing " Kevin Wolf
2022-10-07 10:47 ` [PULL 09/50] file-posix: " Kevin Wolf
2022-10-07 10:47 ` [PULL 10/50] iscsi: " Kevin Wolf
2022-10-07 10:47 ` [PULL 11/50] nbd: " Kevin Wolf
2022-10-07 10:47 ` [PULL 12/50] nfs: " Kevin Wolf
2022-10-07 10:47 ` [PULL 13/50] nvme: " Kevin Wolf
2022-10-07 10:47 ` [PULL 14/50] parallels: " Kevin Wolf
2022-10-07 10:47 ` [PULL 15/50] qcow2: " Kevin Wolf
2022-10-07 10:47 ` [PULL 16/50] copy-before-write: " Kevin Wolf
2022-10-07 10:47 ` [PULL 17/50] curl: " Kevin Wolf
2022-10-07 10:47 ` [PULL 18/50] qed: " Kevin Wolf
2022-10-07 10:47 ` [PULL 19/50] quorum: " Kevin Wolf
2022-10-07 10:47 ` [PULL 20/50] throttle: " Kevin Wolf
2022-10-07 10:47 ` [PULL 21/50] vmdk: " Kevin Wolf
2022-10-07 10:47 ` [PULL 22/50] job: " Kevin Wolf
2022-10-07 10:47 ` [PULL 23/50] coroutine-lock: " Kevin Wolf
2022-10-07 10:47 ` [PULL 24/50] raw-format: " Kevin Wolf
2022-10-07 10:47 ` [PULL 25/50] 9p: " Kevin Wolf
2022-10-07 10:47 ` [PULL 26/50] migration: " Kevin Wolf
2022-10-07 10:47 ` [PULL 27/50] test-coroutine: " Kevin Wolf
2022-10-07 10:47 ` [PULL 28/50] quorum: Remove unnecessary forward declaration Kevin Wolf
2022-10-07 10:47 ` [PULL 29/50] job.c: make job_mutex and job_lock/unlock() public Kevin Wolf
2022-10-07 10:47 ` [PULL 30/50] job.h: categorize fields in struct Job Kevin Wolf
2022-10-07 10:47 ` [PULL 31/50] job.c: API functions not used outside should be static Kevin Wolf
2022-10-07 10:47 ` [PULL 32/50] aio-wait.h: introduce AIO_WAIT_WHILE_UNLOCKED Kevin Wolf
2022-10-07 10:47 ` [PULL 33/50] job.c: add job_lock/unlock while keeping job.h intact Kevin Wolf
2022-10-07 10:47 ` [PULL 34/50] job: move and update comments from blockjob.c Kevin Wolf
2022-10-07 10:47 ` [PULL 35/50] blockjob: introduce block_job _locked() APIs Kevin Wolf
2022-10-07 10:47 ` [PULL 36/50] jobs: add job lock in find_* functions Kevin Wolf
2022-10-07 10:47 ` Kevin Wolf [this message]
2022-10-07 10:47 ` [PULL 38/50] block/mirror.c: use of job helpers in drivers Kevin Wolf
2022-10-07 10:47 ` [PULL 39/50] jobs: group together API calls under the same job lock Kevin Wolf
2022-10-07 10:47 ` [PULL 40/50] job: detect change of aiocontext within job coroutine Kevin Wolf
2022-10-07 10:47 ` [PULL 41/50] jobs: protect job.aio_context with BQL and job_mutex Kevin Wolf
2022-10-07 10:47 ` [PULL 42/50] blockjob.h: categorize fields in struct BlockJob Kevin Wolf
2022-10-07 10:47 ` [PULL 43/50] blockjob: rename notifier callbacks as _locked Kevin Wolf
2022-10-07 10:47 ` [PULL 44/50] blockjob: protect iostatus field in BlockJob struct Kevin Wolf
2022-10-07 10:47 ` [PULL 45/50] job.h: categorize JobDriver callbacks that need the AioContext lock Kevin Wolf
2022-10-07 10:47 ` [PULL 46/50] job.c: enable job lock/unlock and remove Aiocontext locks Kevin Wolf
2022-10-07 10:47 ` [PULL 47/50] block_job_query: remove atomic read Kevin Wolf
2022-10-07 10:47 ` [PULL 48/50] blockjob: remove unused functions Kevin Wolf
2022-10-07 10:47 ` [PULL 49/50] job: " Kevin Wolf
2022-10-07 10:47 ` [PULL 50/50] file-posix: Remove unused s->discard_zeroes Kevin Wolf
2022-10-12 21:25 ` [PULL 00/50] Block layer patches Stefan Hajnoczi

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