diff options
| -rw-r--r-- | block/io.c | 4 | ||||
| -rw-r--r-- | tests/test-bdrv-drain.c | 187 |
2 files changed, 186 insertions, 5 deletions
@@ -370,10 +370,6 @@ void bdrv_unapply_subtree_drain(BdrvChild *child, BlockDriverState *old_parent) * * Note that unlike bdrv_drain_all(), the caller must hold the BlockDriverState * AioContext. - * - * Only this BlockDriverState's AioContext is run, so in-flight requests must - * not depend on events in other AioContexts. In that case, use - * bdrv_drain_all() instead. */ void coroutine_fn bdrv_co_drain(BlockDriverState *bs) { diff --git a/tests/test-bdrv-drain.c b/tests/test-bdrv-drain.c index a11c4cf..fb68539 100644 --- a/tests/test-bdrv-drain.c +++ b/tests/test-bdrv-drain.c @@ -27,9 +27,13 @@ #include "block/blockjob_int.h" #include "sysemu/block-backend.h" #include "qapi/error.h" +#include "iothread.h" + +static QemuEvent done_event; typedef struct BDRVTestState { int drain_count; + AioContext *bh_indirection_ctx; } BDRVTestState; static void coroutine_fn bdrv_test_co_drain_begin(BlockDriverState *bs) @@ -50,16 +54,29 @@ static void bdrv_test_close(BlockDriverState *bs) g_assert_cmpint(s->drain_count, >, 0); } +static void co_reenter_bh(void *opaque) +{ + aio_co_wake(opaque); +} + static int coroutine_fn bdrv_test_co_preadv(BlockDriverState *bs, uint64_t offset, uint64_t bytes, QEMUIOVector *qiov, int flags) { + BDRVTestState *s = bs->opaque; + /* We want this request to stay until the polling loop in drain waits for * it to complete. We need to sleep a while as bdrv_drain_invoke() comes * first and polls its result, too, but it shouldn't accidentally complete * this request yet. */ qemu_co_sleep_ns(QEMU_CLOCK_REALTIME, 100000); + if (s->bh_indirection_ctx) { + aio_bh_schedule_oneshot(s->bh_indirection_ctx, co_reenter_bh, + qemu_coroutine_self()); + qemu_coroutine_yield(); + } + return 0; } @@ -490,6 +507,164 @@ static void test_graph_change(void) blk_unref(blk_b); } +struct test_iothread_data { + BlockDriverState *bs; + enum drain_type drain_type; + int *aio_ret; +}; + +static void test_iothread_drain_entry(void *opaque) +{ + struct test_iothread_data *data = opaque; + + aio_context_acquire(bdrv_get_aio_context(data->bs)); + do_drain_begin(data->drain_type, data->bs); + g_assert_cmpint(*data->aio_ret, ==, 0); + do_drain_end(data->drain_type, data->bs); + aio_context_release(bdrv_get_aio_context(data->bs)); + + qemu_event_set(&done_event); +} + +static void test_iothread_aio_cb(void *opaque, int ret) +{ + int *aio_ret = opaque; + *aio_ret = ret; + qemu_event_set(&done_event); +} + +/* + * Starts an AIO request on a BDS that runs in the AioContext of iothread 1. + * The request involves a BH on iothread 2 before it can complete. + * + * @drain_thread = 0 means that do_drain_begin/end are called from the main + * thread, @drain_thread = 1 means that they are called from iothread 1. Drain + * for this BDS cannot be called from iothread 2 because only the main thread + * may do cross-AioContext polling. + */ +static void test_iothread_common(enum drain_type drain_type, int drain_thread) +{ + BlockBackend *blk; + BlockDriverState *bs; + BDRVTestState *s; + BlockAIOCB *acb; + int aio_ret; + struct test_iothread_data data; + + IOThread *a = iothread_new(); + IOThread *b = iothread_new(); + AioContext *ctx_a = iothread_get_aio_context(a); + AioContext *ctx_b = iothread_get_aio_context(b); + + QEMUIOVector qiov; + struct iovec iov = { + .iov_base = NULL, + .iov_len = 0, + }; + qemu_iovec_init_external(&qiov, &iov, 1); + + /* bdrv_drain_all() may only be called from the main loop thread */ + if (drain_type == BDRV_DRAIN_ALL && drain_thread != 0) { + goto out; + } + + blk = blk_new(BLK_PERM_ALL, BLK_PERM_ALL); + bs = bdrv_new_open_driver(&bdrv_test, "test-node", BDRV_O_RDWR, + &error_abort); + s = bs->opaque; + blk_insert_bs(blk, bs, &error_abort); + + blk_set_aio_context(blk, ctx_a); + aio_context_acquire(ctx_a); + + s->bh_indirection_ctx = ctx_b; + + aio_ret = -EINPROGRESS; + if (drain_thread == 0) { + acb = blk_aio_preadv(blk, 0, &qiov, 0, test_iothread_aio_cb, &aio_ret); + } else { + acb = blk_aio_preadv(blk, 0, &qiov, 0, aio_ret_cb, &aio_ret); + } + g_assert(acb != NULL); + g_assert_cmpint(aio_ret, ==, -EINPROGRESS); + + aio_context_release(ctx_a); + + data = (struct test_iothread_data) { + .bs = bs, + .drain_type = drain_type, + .aio_ret = &aio_ret, + }; + + switch (drain_thread) { + case 0: + if (drain_type != BDRV_DRAIN_ALL) { + aio_context_acquire(ctx_a); + } + + /* The request is running on the IOThread a. Draining its block device + * will make sure that it has completed as far as the BDS is concerned, + * but the drain in this thread can continue immediately after + * bdrv_dec_in_flight() and aio_ret might be assigned only slightly + * later. */ + qemu_event_reset(&done_event); + do_drain_begin(drain_type, bs); + g_assert_cmpint(bs->in_flight, ==, 0); + + if (drain_type != BDRV_DRAIN_ALL) { + aio_context_release(ctx_a); + } + qemu_event_wait(&done_event); + if (drain_type != BDRV_DRAIN_ALL) { + aio_context_acquire(ctx_a); + } + + g_assert_cmpint(aio_ret, ==, 0); + do_drain_end(drain_type, bs); + + if (drain_type != BDRV_DRAIN_ALL) { + aio_context_release(ctx_a); + } + break; + case 1: + qemu_event_reset(&done_event); + aio_bh_schedule_oneshot(ctx_a, test_iothread_drain_entry, &data); + qemu_event_wait(&done_event); + break; + default: + g_assert_not_reached(); + } + + aio_context_acquire(ctx_a); + blk_set_aio_context(blk, qemu_get_aio_context()); + aio_context_release(ctx_a); + + bdrv_unref(bs); + blk_unref(blk); + +out: + iothread_join(a); + iothread_join(b); +} + +static void test_iothread_drain_all(void) +{ + test_iothread_common(BDRV_DRAIN_ALL, 0); + test_iothread_common(BDRV_DRAIN_ALL, 1); +} + +static void test_iothread_drain(void) +{ + test_iothread_common(BDRV_DRAIN, 0); + test_iothread_common(BDRV_DRAIN, 1); +} + +static void test_iothread_drain_subtree(void) +{ + test_iothread_common(BDRV_SUBTREE_DRAIN, 0); + test_iothread_common(BDRV_SUBTREE_DRAIN, 1); +} + typedef struct TestBlockJob { BlockJob common; @@ -618,10 +793,13 @@ static void test_blockjob_drain_subtree(void) int main(int argc, char **argv) { + int ret; + bdrv_init(); qemu_init_main_loop(&error_abort); g_test_init(&argc, &argv, NULL); + qemu_event_init(&done_event, false); g_test_add_func("/bdrv-drain/driver-cb/drain_all", test_drv_cb_drain_all); g_test_add_func("/bdrv-drain/driver-cb/drain", test_drv_cb_drain); @@ -648,10 +826,17 @@ int main(int argc, char **argv) g_test_add_func("/bdrv-drain/multiparent", test_multiparent); g_test_add_func("/bdrv-drain/graph-change", test_graph_change); + g_test_add_func("/bdrv-drain/iothread/drain_all", test_iothread_drain_all); + g_test_add_func("/bdrv-drain/iothread/drain", test_iothread_drain); + g_test_add_func("/bdrv-drain/iothread/drain_subtree", + test_iothread_drain_subtree); + g_test_add_func("/bdrv-drain/blockjob/drain_all", test_blockjob_drain_all); g_test_add_func("/bdrv-drain/blockjob/drain", test_blockjob_drain); g_test_add_func("/bdrv-drain/blockjob/drain_subtree", test_blockjob_drain_subtree); - return g_test_run(); + ret = g_test_run(); + qemu_event_destroy(&done_event); + return ret; } |