[Qemu-devel] [PATCH v2 10/10] tests: add BlockJobTxn unit test

[Stefan Hajnoczi <stefanha@redhat.com>]

The BlockJobTxn unit test verifies that both single jobs and pairs of
jobs behave as a transaction group.  Either all jobs complete
successfully or the group is cancelled.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
---
v2:
 * Test fail/cancel race condition [jsnow]
 * Use new 'transactional-cancel' QMP argument
---
 tests/Makefile            |   3 +
 tests/test-blockjob-txn.c | 233 ++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 236 insertions(+)
 create mode 100644 tests/test-blockjob-txn.c

diff --git a/tests/Makefile b/tests/Makefile
index eff5e11..837f30b 100644
--- a/tests/Makefile
+++ b/tests/Makefile
@@ -45,6 +45,8 @@ check-unit-y += tests/test-thread-pool$(EXESUF)
 gcov-files-test-thread-pool-y = thread-pool.c
 gcov-files-test-hbitmap-y = util/hbitmap.c
 check-unit-y += tests/test-hbitmap$(EXESUF)
+gcov-files-test-hbitmap-y = blockjob.c
+check-unit-y += tests/test-blockjob-txn$(EXESUF)
 check-unit-y += tests/test-x86-cpuid$(EXESUF)
 # all code tested by test-x86-cpuid is inside topology.h
 gcov-files-test-x86-cpuid-y =
@@ -283,6 +285,7 @@ tests/test-coroutine$(EXESUF): tests/test-coroutine.o $(block-obj-y) libqemuutil
 tests/test-aio$(EXESUF): tests/test-aio.o $(block-obj-y) libqemuutil.a libqemustub.a
 tests/test-rfifolock$(EXESUF): tests/test-rfifolock.o libqemuutil.a libqemustub.a
 tests/test-throttle$(EXESUF): tests/test-throttle.o $(block-obj-y) libqemuutil.a libqemustub.a
+tests/test-blockjob-txn$(EXESUF): tests/test-blockjob-txn.o $(block-obj-y) libqemuutil.a libqemustub.a
 tests/test-thread-pool$(EXESUF): tests/test-thread-pool.o $(block-obj-y) libqemuutil.a libqemustub.a
 tests/test-iov$(EXESUF): tests/test-iov.o libqemuutil.a
 tests/test-hbitmap$(EXESUF): tests/test-hbitmap.o libqemuutil.a libqemustub.a
diff --git a/tests/test-blockjob-txn.c b/tests/test-blockjob-txn.c
new file mode 100644
index 0000000..e4d9ee3
--- /dev/null
+++ b/tests/test-blockjob-txn.c
@@ -0,0 +1,233 @@
+/*
+ * Blockjob transactions tests
+ *
+ * Copyright Red Hat, Inc. 2015
+ *
+ * Authors:
+ *  Stefan Hajnoczi    <stefanha@redhat.com>
+ *
+ * This work is licensed under the terms of the GNU LGPL, version 2 or later.
+ * See the COPYING.LIB file in the top-level directory.
+ */
+
+#include <glib.h>
+#include "qapi/error.h"
+#include "qemu/main-loop.h"
+#include "block/blockjob.h"
+
+typedef struct {
+    BlockJob common;
+    unsigned int iterations;
+    bool use_timer;
+    int rc;
+} TestBlockJob;
+
+static const BlockJobDriver test_block_job_driver = {
+    .instance_size = sizeof(TestBlockJob),
+};
+
+static void test_block_job_complete(BlockJob *job, void *opaque)
+{
+    BlockDriverState *bs = job->bs;
+    int rc = (intptr_t)opaque;
+
+    if (block_job_is_cancelled(job)) {
+        rc = -ECANCELED;
+    }
+
+    block_job_completed(job, rc);
+    bdrv_unref(bs);
+}
+
+static void coroutine_fn test_block_job_run(void *opaque)
+{
+    TestBlockJob *s = opaque;
+    BlockJob *job = &s->common;
+
+    while (s->iterations--) {
+        if (s->use_timer) {
+            block_job_sleep_ns(job, QEMU_CLOCK_REALTIME, 0);
+        } else {
+            block_job_yield(job);
+        }
+
+        if (block_job_is_cancelled(job)) {
+            break;
+        }
+    }
+
+    block_job_txn_job_done(job->txn, job, s->rc);
+
+    block_job_defer_to_main_loop(job, test_block_job_complete,
+                                 (void *)(intptr_t)s->rc);
+}
+
+static void test_block_job_cb(void *opaque, int ret)
+{
+    *(int *)opaque = ret;
+}
+
+/* Create a block job that completes with a given return code after a given
+ * number of event loop iterations.  The return code is stored in the given
+ * result pointer.
+ *
+ * The event loop iterations can either be handled automatically with a 0 delay
+ * timer, or they can be stepped manually by entering the coroutine.
+ */
+static BlockJob *test_block_job_start(unsigned int iterations,
+                                      bool use_timer,
+                                      int rc, int *result)
+{
+    BlockDriverState *bs;
+    TestBlockJob *s;
+
+    bs = bdrv_new();
+    s = block_job_create(&test_block_job_driver, bs, 0, test_block_job_cb,
+                         result, &error_abort);
+    s->iterations = iterations;
+    s->use_timer = use_timer;
+    s->rc = rc;
+    s->common.co = qemu_coroutine_create(test_block_job_run);
+    qemu_coroutine_enter(s->common.co, s);
+    return &s->common;
+}
+
+static void test_single_job(int expected)
+{
+    BlockJob *job;
+    BlockJobTxn *txn;
+    int result = -EINPROGRESS;
+
+    txn = block_job_txn_new();
+    job = test_block_job_start(1, true, expected, &result);
+    block_job_txn_add_job(txn, job);
+    block_job_txn_begin(&txn);
+
+    if (expected == -ECANCELED) {
+        block_job_cancel(job);
+    }
+
+    while (result == -EINPROGRESS) {
+        aio_poll(qemu_get_aio_context(), true);
+    }
+    g_assert_cmpint(result, ==, expected);
+}
+
+static void test_single_job_success(void)
+{
+    test_single_job(0);
+}
+
+static void test_single_job_failure(void)
+{
+    test_single_job(-EIO);
+}
+
+static void test_single_job_cancel(void)
+{
+    test_single_job(-ECANCELED);
+}
+
+static void test_pair_jobs(int expected1, int expected2)
+{
+    BlockJob *job1;
+    BlockJob *job2;
+    BlockJobTxn *txn;
+    int result1 = -EINPROGRESS;
+    int result2 = -EINPROGRESS;
+
+    txn = block_job_txn_new();
+    job1 = test_block_job_start(1, true, expected1, &result1);
+    block_job_txn_add_job(txn, job1);
+    job2 = test_block_job_start(2, true, expected2, &result2);
+    block_job_txn_add_job(txn, job2);
+    block_job_txn_begin(&txn);
+
+    if (expected1 == -ECANCELED) {
+        block_job_cancel(job1);
+    }
+    if (expected2 == -ECANCELED) {
+        block_job_cancel(job2);
+    }
+
+    while (result1 == -EINPROGRESS || result2 == -EINPROGRESS) {
+        aio_poll(qemu_get_aio_context(), true);
+    }
+
+    /* Failure or cancellation of one job cancels the other job */
+    if (expected1 != 0) {
+        expected2 = -ECANCELED;
+    } else if (expected2 != 0) {
+        expected1 = -ECANCELED;
+    }
+
+    g_assert_cmpint(result1, ==, expected1);
+    g_assert_cmpint(result2, ==, expected2);
+}
+
+static void test_pair_jobs_success(void)
+{
+    test_pair_jobs(0, 0);
+}
+
+static void test_pair_jobs_failure(void)
+{
+    /* Test both orderings.  The two jobs run for a different number of
+     * iterations so the code path is different depending on which job fails
+     * first.
+     */
+    test_pair_jobs(-EIO, 0);
+    test_pair_jobs(0, -EIO);
+}
+
+static void test_pair_jobs_cancel(void)
+{
+    test_pair_jobs(-ECANCELED, 0);
+    test_pair_jobs(0, -ECANCELED);
+}
+
+static void test_pair_jobs_fail_cancel_race(void)
+{
+    BlockJob *job1;
+    BlockJob *job2;
+    BlockJobTxn *txn;
+    int result1 = -EINPROGRESS;
+    int result2 = -EINPROGRESS;
+
+    txn = block_job_txn_new();
+    job1 = test_block_job_start(1, true, -ECANCELED, &result1);
+    block_job_txn_add_job(txn, job1);
+    job2 = test_block_job_start(2, false, 0, &result2);
+    block_job_txn_add_job(txn, job2);
+    block_job_txn_begin(&txn);
+
+    block_job_cancel(job1);
+
+    /* Now make job2 finish before the main loop kicks jobs.  This means
+     * simulates the race between a pending kick and another job completing.
+     */
+    block_job_enter(job2);
+    block_job_enter(job2);
+
+    while (result1 == -EINPROGRESS || result2 == -EINPROGRESS) {
+        aio_poll(qemu_get_aio_context(), true);
+    }
+
+    g_assert_cmpint(result1, ==, -ECANCELED);
+    g_assert_cmpint(result2, ==, -ECANCELED);
+}
+
+int main(int argc, char **argv)
+{
+    qemu_init_main_loop(&error_abort);
+
+    g_test_init(&argc, &argv, NULL);
+    g_test_add_func("/single/success", test_single_job_success);
+    g_test_add_func("/single/failure", test_single_job_failure);
+    g_test_add_func("/single/cancel", test_single_job_cancel);
+    g_test_add_func("/pair/success", test_pair_jobs_success);
+    g_test_add_func("/pair/failure", test_pair_jobs_failure);
+    g_test_add_func("/pair/cancel", test_pair_jobs_cancel);
+    g_test_add_func("/pair/fail-cancel-race", test_pair_jobs_fail_cancel_race);
+    return g_test_run();
+}
-- 
2.4.3