Many write-lockded sections are also drained sections. A new bdrv_graph_wrunlock_drained() wrapper around bdrv_graph_wrunlock() is introduced, which will begin a drained section first. A global variable is used so bdrv_graph_wrunlock() knows if it also needs to end such a drained section. Both the aio_poll call in bdrv_graph_wrlock() and the aio_bh_poll() in bdrv_graph_wrunlock() can re-enter a write-locked section. While for the latter, ending the drain could be moved to before the call, the former requires that the variable is a counter and not just a boolean.
The switch to the new helpers was generated with the following commands and then manually checked: find . -name '*.c' -exec sed -i -z 's/bdrv_drain_all_begin();\n\s*bdrv_graph_wrlock();/bdrv_graph_wrlock_drained();/g' {} ';' find . -name '*.c' -exec sed -i -z 's/bdrv_graph_wrunlock();\n\s*bdrv_drain_all_end();/bdrv_graph_wrunlock();/g' {} ';' Suggested-by: Kevin Wolf <kw...@redhat.com> Signed-off-by: Fiona Ebner <f.eb...@proxmox.com> --- In the RFC, I had tried Coccinelle before sed, but it seemed to not work in certain source files, maybe it was not happy with some macros? Changes in v2: * Add convenience wrapper rather than introducing a new flag argument. block.c | 20 ++++------------ block/backup.c | 4 +--- block/blklogwrites.c | 8 ++----- block/blkverify.c | 4 +--- block/block-backend.c | 8 ++----- block/commit.c | 6 +---- block/graph-lock.c | 40 +++++++++++++++++++++++++++++--- block/mirror.c | 7 +----- block/qcow2.c | 4 +--- block/quorum.c | 8 ++----- block/replication.c | 11 ++------- block/snapshot.c | 4 +--- block/stream.c | 6 +---- block/vmdk.c | 20 ++++------------ blockdev.c | 4 +--- blockjob.c | 10 ++------ include/block/graph-lock.h | 11 +++++++++ tests/unit/test-bdrv-drain.c | 36 +++++++--------------------- tests/unit/test-bdrv-graph-mod.c | 20 ++++------------ 19 files changed, 90 insertions(+), 141 deletions(-) diff --git a/block.c b/block.c index dfe665e457..dbd07b1a42 100644 --- a/block.c +++ b/block.c @@ -1721,14 +1721,12 @@ bdrv_open_driver(BlockDriverState *bs, BlockDriver *drv, const char *node_name, open_failed: bs->drv = NULL; - bdrv_drain_all_begin(); - bdrv_graph_wrlock(); + bdrv_graph_wrlock_drained(); if (bs->file != NULL) { bdrv_unref_child(bs, bs->file); assert(!bs->file); } bdrv_graph_wrunlock(); - bdrv_drain_all_end(); g_free(bs->opaque); bs->opaque = NULL; @@ -3588,11 +3586,9 @@ int bdrv_set_backing_hd(BlockDriverState *bs, BlockDriverState *backing_hd, bdrv_graph_rdunlock_main_loop(); bdrv_ref(drain_bs); - bdrv_drain_all_begin(); - bdrv_graph_wrlock(); + bdrv_graph_wrlock_drained(); ret = bdrv_set_backing_hd_drained(bs, backing_hd, errp); bdrv_graph_wrunlock(); - bdrv_drain_all_end(); bdrv_unref(drain_bs); return ret; @@ -3784,12 +3780,10 @@ static BdrvChild *bdrv_open_child_common(const char *filename, return NULL; } - bdrv_drain_all_begin(); - bdrv_graph_wrlock(); + bdrv_graph_wrlock_drained(); child = bdrv_attach_child(parent, bs, bdref_key, child_class, child_role, errp); bdrv_graph_wrunlock(); - bdrv_drain_all_end(); return child; } @@ -5163,8 +5157,7 @@ static void bdrv_close(BlockDriverState *bs) bs->drv = NULL; } - bdrv_drain_all_begin(); - bdrv_graph_wrlock(); + bdrv_graph_wrlock_drained(); QLIST_FOREACH_SAFE(child, &bs->children, next, next) { bdrv_unref_child(bs, child); } @@ -5172,7 +5165,6 @@ static void bdrv_close(BlockDriverState *bs) assert(!bs->backing); assert(!bs->file); bdrv_graph_wrunlock(); - bdrv_drain_all_end(); g_free(bs->opaque); bs->opaque = NULL; @@ -5498,8 +5490,7 @@ int bdrv_append(BlockDriverState *bs_new, BlockDriverState *bs_top, assert(!bs_new->backing); bdrv_graph_rdunlock_main_loop(); - bdrv_drain_all_begin(); - bdrv_graph_wrlock(); + bdrv_graph_wrlock_drained(); child = bdrv_attach_child_noperm(bs_new, bs_top, "backing", &child_of_bds, bdrv_backing_role(bs_new), @@ -5520,7 +5511,6 @@ out: bdrv_refresh_limits(bs_top, NULL, NULL); bdrv_graph_wrunlock(); - bdrv_drain_all_end(); return ret; } diff --git a/block/backup.c b/block/backup.c index 909027c17a..d4713fa1cd 100644 --- a/block/backup.c +++ b/block/backup.c @@ -498,12 +498,10 @@ BlockJob *backup_job_create(const char *job_id, BlockDriverState *bs, block_copy_set_speed(bcs, speed); /* Required permissions are taken by copy-before-write filter target */ - bdrv_drain_all_begin(); - bdrv_graph_wrlock(); + bdrv_graph_wrlock_drained(); block_job_add_bdrv(&job->common, "target", target, 0, BLK_PERM_ALL, &error_abort); bdrv_graph_wrunlock(); - bdrv_drain_all_end(); return &job->common; diff --git a/block/blklogwrites.c b/block/blklogwrites.c index 70ac76f401..aa1f888869 100644 --- a/block/blklogwrites.c +++ b/block/blklogwrites.c @@ -281,11 +281,9 @@ static int blk_log_writes_open(BlockDriverState *bs, QDict *options, int flags, ret = 0; fail_log: if (ret < 0) { - bdrv_drain_all_begin(); - bdrv_graph_wrlock(); + bdrv_graph_wrlock_drained(); bdrv_unref_child(bs, s->log_file); bdrv_graph_wrunlock(); - bdrv_drain_all_end(); s->log_file = NULL; qemu_mutex_destroy(&s->mutex); } @@ -298,12 +296,10 @@ static void blk_log_writes_close(BlockDriverState *bs) { BDRVBlkLogWritesState *s = bs->opaque; - bdrv_drain_all_begin(); - bdrv_graph_wrlock(); + bdrv_graph_wrlock_drained(); bdrv_unref_child(bs, s->log_file); s->log_file = NULL; bdrv_graph_wrunlock(); - bdrv_drain_all_end(); qemu_mutex_destroy(&s->mutex); } diff --git a/block/blkverify.c b/block/blkverify.c index 3a71f7498c..72efcbe7ef 100644 --- a/block/blkverify.c +++ b/block/blkverify.c @@ -151,12 +151,10 @@ static void blkverify_close(BlockDriverState *bs) { BDRVBlkverifyState *s = bs->opaque; - bdrv_drain_all_begin(); - bdrv_graph_wrlock(); + bdrv_graph_wrlock_drained(); bdrv_unref_child(bs, s->test_file); s->test_file = NULL; bdrv_graph_wrunlock(); - bdrv_drain_all_end(); } static int64_t coroutine_fn GRAPH_RDLOCK diff --git a/block/block-backend.c b/block/block-backend.c index 68209bb2f7..f8d6ba65c1 100644 --- a/block/block-backend.c +++ b/block/block-backend.c @@ -889,11 +889,9 @@ void blk_remove_bs(BlockBackend *blk) root = blk->root; blk->root = NULL; - bdrv_drain_all_begin(); - bdrv_graph_wrlock(); + bdrv_graph_wrlock_drained(); bdrv_root_unref_child(root); bdrv_graph_wrunlock(); - bdrv_drain_all_end(); } /* @@ -906,8 +904,7 @@ int blk_insert_bs(BlockBackend *blk, BlockDriverState *bs, Error **errp) GLOBAL_STATE_CODE(); bdrv_ref(bs); - bdrv_drain_all_begin(); - bdrv_graph_wrlock(); + bdrv_graph_wrlock_drained(); if ((bs->open_flags & BDRV_O_INACTIVE) && blk_can_inactivate(blk)) { blk->disable_perm = true; @@ -922,7 +919,6 @@ int blk_insert_bs(BlockBackend *blk, BlockDriverState *bs, Error **errp) BDRV_CHILD_FILTERED | BDRV_CHILD_PRIMARY, perm, shared_perm, blk, errp); bdrv_graph_wrunlock(); - bdrv_drain_all_end(); if (blk->root == NULL) { return -EPERM; } diff --git a/block/commit.c b/block/commit.c index 6c4b736ff8..dc1942483b 100644 --- a/block/commit.c +++ b/block/commit.c @@ -392,8 +392,7 @@ void commit_start(const char *job_id, BlockDriverState *bs, * this is the responsibility of the interface (i.e. whoever calls * commit_start()). */ - bdrv_drain_all_begin(); - bdrv_graph_wrlock(); + bdrv_graph_wrlock_drained(); s->base_overlay = bdrv_find_overlay(top, base); assert(s->base_overlay); @@ -425,21 +424,18 @@ void commit_start(const char *job_id, BlockDriverState *bs, iter_shared_perms, errp); if (ret < 0) { bdrv_graph_wrunlock(); - bdrv_drain_all_end(); goto fail; } } if (bdrv_freeze_backing_chain(commit_top_bs, base, errp) < 0) { bdrv_graph_wrunlock(); - bdrv_drain_all_end(); goto fail; } s->chain_frozen = true; ret = block_job_add_bdrv(&s->common, "base", base, 0, BLK_PERM_ALL, errp); bdrv_graph_wrunlock(); - bdrv_drain_all_end(); if (ret < 0) { goto fail; diff --git a/block/graph-lock.c b/block/graph-lock.c index c81162b147..b7319473a1 100644 --- a/block/graph-lock.c +++ b/block/graph-lock.c @@ -33,6 +33,17 @@ static QemuMutex aio_context_list_lock; /* Written and read with atomic operations. */ static int has_writer; +/* + * Many write-locked sections are also drained sections. There is a convenience + * wrapper bdrv_graph_wrlock_drained() which begins a drained section before + * acquiring the lock. This variable here is used so bdrv_graph_wrunlock() knows + * if it also needs to end such a drained section. It needs to be a counter, + * because the aio_poll() call in bdrv_graph_wrlock() might re-enter + * bdrv_graph_wrlock_drained(). And note that aio_bh_poll() in + * bdrv_graph_wrunlock() might also re-enter a write-locked section. + */ +static int wrlock_quiesced_counter; + /* * A reader coroutine could move from an AioContext to another. * If this happens, there is no problem from the point of view of @@ -112,8 +123,14 @@ void no_coroutine_fn bdrv_graph_wrlock(void) assert(!qatomic_read(&has_writer)); assert(!qemu_in_coroutine()); - /* Make sure that constantly arriving new I/O doesn't cause starvation */ - bdrv_drain_all_begin_nopoll(); + bool need_drain = wrlock_quiesced_counter == 0; + + if (need_drain) { + /* + * Make sure that constantly arriving new I/O doesn't cause starvation + */ + bdrv_drain_all_begin_nopoll(); + } /* * reader_count == 0: this means writer will read has_reader as 1 @@ -139,7 +156,18 @@ void no_coroutine_fn bdrv_graph_wrlock(void) smp_mb(); } while (reader_count() >= 1); - bdrv_drain_all_end(); + if (need_drain) { + bdrv_drain_all_end(); + } +} + +void no_coroutine_fn bdrv_graph_wrlock_drained(void) +{ + GLOBAL_STATE_CODE(); + + bdrv_drain_all_begin(); + wrlock_quiesced_counter++; + bdrv_graph_wrlock(); } void no_coroutine_fn bdrv_graph_wrunlock(void) @@ -168,6 +196,12 @@ void no_coroutine_fn bdrv_graph_wrunlock(void) * progress. */ aio_bh_poll(qemu_get_aio_context()); + + if (wrlock_quiesced_counter > 0) { + bdrv_drain_all_end(); + wrlock_quiesced_counter--; + } + } void coroutine_fn bdrv_graph_co_rdlock(void) diff --git a/block/mirror.c b/block/mirror.c index 6e8caf4b49..82a6e50cf8 100644 --- a/block/mirror.c +++ b/block/mirror.c @@ -2014,15 +2014,13 @@ static BlockJob *mirror_start_job( */ bdrv_disable_dirty_bitmap(s->dirty_bitmap); - bdrv_drain_all_begin(); - bdrv_graph_wrlock(); + bdrv_graph_wrlock_drained(); ret = block_job_add_bdrv(&s->common, "source", bs, 0, BLK_PERM_WRITE_UNCHANGED | BLK_PERM_WRITE | BLK_PERM_CONSISTENT_READ, errp); if (ret < 0) { bdrv_graph_wrunlock(); - bdrv_drain_all_end(); goto fail; } @@ -2068,19 +2066,16 @@ static BlockJob *mirror_start_job( iter_shared_perms, errp); if (ret < 0) { bdrv_graph_wrunlock(); - bdrv_drain_all_end(); goto fail; } } if (bdrv_freeze_backing_chain(mirror_top_bs, target, errp) < 0) { bdrv_graph_wrunlock(); - bdrv_drain_all_end(); goto fail; } } bdrv_graph_wrunlock(); - bdrv_drain_all_end(); QTAILQ_INIT(&s->ops_in_flight); diff --git a/block/qcow2.c b/block/qcow2.c index 420918b3c3..694ad797dc 100644 --- a/block/qcow2.c +++ b/block/qcow2.c @@ -2821,11 +2821,9 @@ qcow2_do_close(BlockDriverState *bs, bool close_data_file) if (close_data_file && has_data_file(bs)) { GLOBAL_STATE_CODE(); bdrv_graph_rdunlock_main_loop(); - bdrv_drain_all_begin(); - bdrv_graph_wrlock(); + bdrv_graph_wrlock_drained(); bdrv_unref_child(bs, s->data_file); bdrv_graph_wrunlock(); - bdrv_drain_all_end(); s->data_file = NULL; bdrv_graph_rdlock_main_loop(); } diff --git a/block/quorum.c b/block/quorum.c index cc3bc5f4e7..76a4feb2d9 100644 --- a/block/quorum.c +++ b/block/quorum.c @@ -1037,8 +1037,7 @@ static int quorum_open(BlockDriverState *bs, QDict *options, int flags, close_exit: /* cleanup on error */ - bdrv_drain_all_begin(); - bdrv_graph_wrlock(); + bdrv_graph_wrlock_drained(); for (i = 0; i < s->num_children; i++) { if (!opened[i]) { continue; @@ -1046,7 +1045,6 @@ close_exit: bdrv_unref_child(bs, s->children[i]); } bdrv_graph_wrunlock(); - bdrv_drain_all_end(); g_free(s->children); g_free(opened); exit: @@ -1059,13 +1057,11 @@ static void quorum_close(BlockDriverState *bs) BDRVQuorumState *s = bs->opaque; int i; - bdrv_drain_all_begin(); - bdrv_graph_wrlock(); + bdrv_graph_wrlock_drained(); for (i = 0; i < s->num_children; i++) { bdrv_unref_child(bs, s->children[i]); } bdrv_graph_wrunlock(); - bdrv_drain_all_end(); g_free(s->children); } diff --git a/block/replication.c b/block/replication.c index 0879718854..83978b61f5 100644 --- a/block/replication.c +++ b/block/replication.c @@ -540,8 +540,7 @@ static void replication_start(ReplicationState *rs, ReplicationMode mode, return; } - bdrv_drain_all_begin(); - bdrv_graph_wrlock(); + bdrv_graph_wrlock_drained(); bdrv_ref(hidden_disk->bs); s->hidden_disk = bdrv_attach_child(bs, hidden_disk->bs, "hidden disk", @@ -550,7 +549,6 @@ static void replication_start(ReplicationState *rs, ReplicationMode mode, if (local_err) { error_propagate(errp, local_err); bdrv_graph_wrunlock(); - bdrv_drain_all_end(); return; } @@ -561,7 +559,6 @@ static void replication_start(ReplicationState *rs, ReplicationMode mode, if (local_err) { error_propagate(errp, local_err); bdrv_graph_wrunlock(); - bdrv_drain_all_end(); return; } @@ -574,14 +571,12 @@ static void replication_start(ReplicationState *rs, ReplicationMode mode, !check_top_bs(top_bs, bs)) { error_setg(errp, "No top_bs or it is invalid"); bdrv_graph_wrunlock(); - bdrv_drain_all_end(); reopen_backing_file(bs, false, NULL); return; } bdrv_op_block_all(top_bs, s->blocker); bdrv_graph_wrunlock(); - bdrv_drain_all_end(); s->backup_job = backup_job_create( NULL, s->secondary_disk->bs, s->hidden_disk->bs, @@ -656,14 +651,12 @@ static void replication_done(void *opaque, int ret) if (ret == 0) { s->stage = BLOCK_REPLICATION_DONE; - bdrv_drain_all_begin(); - bdrv_graph_wrlock(); + bdrv_graph_wrlock_drained(); bdrv_unref_child(bs, s->secondary_disk); s->secondary_disk = NULL; bdrv_unref_child(bs, s->hidden_disk); s->hidden_disk = NULL; bdrv_graph_wrunlock(); - bdrv_drain_all_end(); s->error = 0; } else { diff --git a/block/snapshot.c b/block/snapshot.c index 28c9c43621..bd9d759b32 100644 --- a/block/snapshot.c +++ b/block/snapshot.c @@ -291,11 +291,9 @@ int bdrv_snapshot_goto(BlockDriverState *bs, } /* .bdrv_open() will re-attach it */ - bdrv_drain_all_begin(); - bdrv_graph_wrlock(); + bdrv_graph_wrlock_drained(); bdrv_unref_child(bs, fallback); bdrv_graph_wrunlock(); - bdrv_drain_all_end(); ret = bdrv_snapshot_goto(fallback_bs, snapshot_id, errp); memset(bs->opaque, 0, drv->instance_size); diff --git a/block/stream.c b/block/stream.c index f5441f27f4..a6ef840e29 100644 --- a/block/stream.c +++ b/block/stream.c @@ -371,12 +371,10 @@ void stream_start(const char *job_id, BlockDriverState *bs, * already have our own plans. Also don't allow resize as the image size is * queried only at the job start and then cached. */ - bdrv_drain_all_begin(); - bdrv_graph_wrlock(); + bdrv_graph_wrlock_drained(); if (block_job_add_bdrv(&s->common, "active node", bs, 0, basic_flags | BLK_PERM_WRITE, errp)) { bdrv_graph_wrunlock(); - bdrv_drain_all_end(); goto fail; } @@ -397,12 +395,10 @@ void stream_start(const char *job_id, BlockDriverState *bs, basic_flags, errp); if (ret < 0) { bdrv_graph_wrunlock(); - bdrv_drain_all_end(); goto fail; } } bdrv_graph_wrunlock(); - bdrv_drain_all_end(); s->base_overlay = base_overlay; s->above_base = above_base; diff --git a/block/vmdk.c b/block/vmdk.c index 89a7250120..04986c8d55 100644 --- a/block/vmdk.c +++ b/block/vmdk.c @@ -271,8 +271,7 @@ static void vmdk_free_extents(BlockDriverState *bs) BDRVVmdkState *s = bs->opaque; VmdkExtent *e; - bdrv_drain_all_begin(); - bdrv_graph_wrlock(); + bdrv_graph_wrlock_drained(); for (i = 0; i < s->num_extents; i++) { e = &s->extents[i]; g_free(e->l1_table); @@ -284,7 +283,6 @@ static void vmdk_free_extents(BlockDriverState *bs) } } bdrv_graph_wrunlock(); - bdrv_drain_all_end(); g_free(s->extents); } @@ -1249,11 +1247,9 @@ vmdk_parse_extents(const char *desc, BlockDriverState *bs, QDict *options, 0, 0, 0, 0, 0, &extent, errp); if (ret < 0) { bdrv_graph_rdunlock_main_loop(); - bdrv_drain_all_begin(); - bdrv_graph_wrlock(); + bdrv_graph_wrlock_drained(); bdrv_unref_child(bs, extent_file); bdrv_graph_wrunlock(); - bdrv_drain_all_end(); bdrv_graph_rdlock_main_loop(); goto out; } @@ -1270,11 +1266,9 @@ vmdk_parse_extents(const char *desc, BlockDriverState *bs, QDict *options, g_free(buf); if (ret) { bdrv_graph_rdunlock_main_loop(); - bdrv_drain_all_begin(); - bdrv_graph_wrlock(); + bdrv_graph_wrlock_drained(); bdrv_unref_child(bs, extent_file); bdrv_graph_wrunlock(); - bdrv_drain_all_end(); bdrv_graph_rdlock_main_loop(); goto out; } @@ -1283,11 +1277,9 @@ vmdk_parse_extents(const char *desc, BlockDriverState *bs, QDict *options, ret = vmdk_open_se_sparse(bs, extent_file, bs->open_flags, errp); if (ret) { bdrv_graph_rdunlock_main_loop(); - bdrv_drain_all_begin(); - bdrv_graph_wrlock(); + bdrv_graph_wrlock_drained(); bdrv_unref_child(bs, extent_file); bdrv_graph_wrunlock(); - bdrv_drain_all_end(); bdrv_graph_rdlock_main_loop(); goto out; } @@ -1295,11 +1287,9 @@ vmdk_parse_extents(const char *desc, BlockDriverState *bs, QDict *options, } else { error_setg(errp, "Unsupported extent type '%s'", type); bdrv_graph_rdunlock_main_loop(); - bdrv_drain_all_begin(); - bdrv_graph_wrlock(); + bdrv_graph_wrlock_drained(); bdrv_unref_child(bs, extent_file); bdrv_graph_wrunlock(); - bdrv_drain_all_end(); bdrv_graph_rdlock_main_loop(); ret = -ENOTSUP; goto out; diff --git a/blockdev.c b/blockdev.c index 2e7fda6780..e625534925 100644 --- a/blockdev.c +++ b/blockdev.c @@ -3561,8 +3561,7 @@ void qmp_x_blockdev_change(const char *parent, const char *child, BlockDriverState *parent_bs, *new_bs = NULL; BdrvChild *p_child; - bdrv_drain_all_begin(); - bdrv_graph_wrlock(); + bdrv_graph_wrlock_drained(); parent_bs = bdrv_lookup_bs(parent, parent, errp); if (!parent_bs) { @@ -3599,7 +3598,6 @@ void qmp_x_blockdev_change(const char *parent, const char *child, out: bdrv_graph_wrunlock(); - bdrv_drain_all_end(); } BlockJobInfoList *qmp_query_block_jobs(Error **errp) diff --git a/blockjob.c b/blockjob.c index e68181a35b..db7c3a69a0 100644 --- a/blockjob.c +++ b/blockjob.c @@ -198,8 +198,7 @@ void block_job_remove_all_bdrv(BlockJob *job) * one to make sure that such a concurrent access does not attempt * to process an already freed BdrvChild. */ - bdrv_drain_all_begin(); - bdrv_graph_wrlock(); + bdrv_graph_wrlock_drained(); while (job->nodes) { GSList *l = job->nodes; BdrvChild *c = l->data; @@ -212,7 +211,6 @@ void block_job_remove_all_bdrv(BlockJob *job) g_slist_free_1(l); } bdrv_graph_wrunlock(); - bdrv_drain_all_end(); } bool block_job_has_bdrv(BlockJob *job, BlockDriverState *bs) @@ -498,8 +496,7 @@ void *block_job_create(const char *job_id, const BlockJobDriver *driver, int ret; GLOBAL_STATE_CODE(); - bdrv_drain_all_begin(); - bdrv_graph_wrlock(); + bdrv_graph_wrlock_drained(); if (job_id == NULL && !(flags & JOB_INTERNAL)) { job_id = bdrv_get_device_name(bs); @@ -509,7 +506,6 @@ void *block_job_create(const char *job_id, const BlockJobDriver *driver, flags, cb, opaque, errp); if (job == NULL) { bdrv_graph_wrunlock(); - bdrv_drain_all_end(); return NULL; } @@ -548,12 +544,10 @@ void *block_job_create(const char *job_id, const BlockJobDriver *driver, } bdrv_graph_wrunlock(); - bdrv_drain_all_end(); return job; fail: bdrv_graph_wrunlock(); - bdrv_drain_all_end(); job_early_fail(&job->job); return NULL; } diff --git a/include/block/graph-lock.h b/include/block/graph-lock.h index 2c26c72108..95bf5ede40 100644 --- a/include/block/graph-lock.h +++ b/include/block/graph-lock.h @@ -112,10 +112,21 @@ void unregister_aiocontext(AioContext *ctx); void no_coroutine_fn TSA_ACQUIRE(graph_lock) TSA_NO_TSA bdrv_graph_wrlock(void); +/* + * bdrv_graph_wrlock_drained: + * Similar to bdrv_graph_wrlock, but will begin a drained section before + * locking. + */ +void no_coroutine_fn TSA_ACQUIRE(graph_lock) TSA_NO_TSA +bdrv_graph_wrlock_drained(void); + /* * bdrv_graph_wrunlock: * Write finished, reset global has_writer to 0 and restart * all readers that are waiting. + * + * Also ends the drained section if bdrv_graph_wrlock_drained() was used to lock + * the graph. */ void no_coroutine_fn TSA_RELEASE(graph_lock) TSA_NO_TSA bdrv_graph_wrunlock(void); diff --git a/tests/unit/test-bdrv-drain.c b/tests/unit/test-bdrv-drain.c index c33f7d31c2..ed60e1693d 100644 --- a/tests/unit/test-bdrv-drain.c +++ b/tests/unit/test-bdrv-drain.c @@ -772,11 +772,9 @@ static void test_blockjob_common_drain_node(enum drain_type drain_type, tjob->bs = src; job = &tjob->common; - bdrv_drain_all_begin(); - bdrv_graph_wrlock(); + bdrv_graph_wrlock_drained(); block_job_add_bdrv(job, "target", target, 0, BLK_PERM_ALL, &error_abort); bdrv_graph_wrunlock(); - bdrv_drain_all_end(); switch (result) { case TEST_JOB_SUCCESS: @@ -955,13 +953,11 @@ static void bdrv_test_top_close(BlockDriverState *bs) { BdrvChild *c, *next_c; - bdrv_drain_all_begin(); - bdrv_graph_wrlock(); + bdrv_graph_wrlock_drained(); QLIST_FOREACH_SAFE(c, &bs->children, next, next_c) { bdrv_unref_child(bs, c); } bdrv_graph_wrunlock(); - bdrv_drain_all_end(); } static int coroutine_fn GRAPH_RDLOCK @@ -1051,12 +1047,10 @@ static void do_test_delete_by_drain(bool detach_instead_of_delete, null_bs = bdrv_open("null-co://", NULL, NULL, BDRV_O_RDWR | BDRV_O_PROTOCOL, &error_abort); - bdrv_drain_all_begin(); - bdrv_graph_wrlock(); + bdrv_graph_wrlock_drained(); bdrv_attach_child(bs, null_bs, "null-child", &child_of_bds, BDRV_CHILD_DATA, &error_abort); bdrv_graph_wrunlock(); - bdrv_drain_all_end(); /* This child will be the one to pass to requests through to, and * it will stall until a drain occurs */ @@ -1064,25 +1058,21 @@ static void do_test_delete_by_drain(bool detach_instead_of_delete, &error_abort); child_bs->total_sectors = 65536 >> BDRV_SECTOR_BITS; /* Takes our reference to child_bs */ - bdrv_drain_all_begin(); - bdrv_graph_wrlock(); + bdrv_graph_wrlock_drained(); tts->wait_child = bdrv_attach_child(bs, child_bs, "wait-child", &child_of_bds, BDRV_CHILD_DATA | BDRV_CHILD_PRIMARY, &error_abort); bdrv_graph_wrunlock(); - bdrv_drain_all_end(); /* This child is just there to be deleted * (for detach_instead_of_delete == true) */ null_bs = bdrv_open("null-co://", NULL, NULL, BDRV_O_RDWR | BDRV_O_PROTOCOL, &error_abort); - bdrv_drain_all_begin(); - bdrv_graph_wrlock(); + bdrv_graph_wrlock_drained(); bdrv_attach_child(bs, null_bs, "null-child", &child_of_bds, BDRV_CHILD_DATA, &error_abort); bdrv_graph_wrunlock(); - bdrv_drain_all_end(); blk = blk_new(qemu_get_aio_context(), BLK_PERM_ALL, BLK_PERM_ALL); blk_insert_bs(blk, bs, &error_abort); @@ -1165,8 +1155,7 @@ static void no_coroutine_fn detach_indirect_bh(void *opaque) bdrv_dec_in_flight(data->child_b->bs); - bdrv_drain_all_begin(); - bdrv_graph_wrlock(); + bdrv_graph_wrlock_drained(); bdrv_unref_child(data->parent_b, data->child_b); bdrv_ref(data->c); @@ -1174,7 +1163,6 @@ static void no_coroutine_fn detach_indirect_bh(void *opaque) &child_of_bds, BDRV_CHILD_DATA, &error_abort); bdrv_graph_wrunlock(); - bdrv_drain_all_end(); } static void coroutine_mixed_fn detach_by_parent_aio_cb(void *opaque, int ret) @@ -1272,8 +1260,7 @@ static void TSA_NO_TSA test_detach_indirect(bool by_parent_cb) /* Set child relationships */ bdrv_ref(b); bdrv_ref(a); - bdrv_drain_all_begin(); - bdrv_graph_wrlock(); + bdrv_graph_wrlock_drained(); child_b = bdrv_attach_child(parent_b, b, "PB-B", &child_of_bds, BDRV_CHILD_DATA, &error_abort); child_a = bdrv_attach_child(parent_b, a, "PB-A", &child_of_bds, @@ -1284,7 +1271,6 @@ static void TSA_NO_TSA test_detach_indirect(bool by_parent_cb) by_parent_cb ? &child_of_bds : &detach_by_driver_cb_class, BDRV_CHILD_DATA, &error_abort); bdrv_graph_wrunlock(); - bdrv_drain_all_end(); g_assert_cmpint(parent_a->refcnt, ==, 1); g_assert_cmpint(parent_b->refcnt, ==, 1); @@ -1697,8 +1683,7 @@ static void test_drop_intermediate_poll(void) * Establish the chain last, so the chain links are the first * elements in the BDS.parents lists */ - bdrv_drain_all_begin(); - bdrv_graph_wrlock(); + bdrv_graph_wrlock_drained(); for (i = 0; i < 3; i++) { if (i) { /* Takes the reference to chain[i - 1] */ @@ -1707,7 +1692,6 @@ static void test_drop_intermediate_poll(void) } } bdrv_graph_wrunlock(); - bdrv_drain_all_end(); job = block_job_create("job", &test_simple_job_driver, NULL, job_node, 0, BLK_PERM_ALL, 0, 0, NULL, NULL, &error_abort); @@ -1954,12 +1938,10 @@ static void do_test_replace_child_mid_drain(int old_drain_count, new_child_bs->total_sectors = 1; bdrv_ref(old_child_bs); - bdrv_drain_all_begin(); - bdrv_graph_wrlock(); + bdrv_graph_wrlock_drained(); bdrv_attach_child(parent_bs, old_child_bs, "child", &child_of_bds, BDRV_CHILD_COW, &error_abort); bdrv_graph_wrunlock(); - bdrv_drain_all_end(); parent_s->setup_completed = true; for (i = 0; i < old_drain_count; i++) { diff --git a/tests/unit/test-bdrv-graph-mod.c b/tests/unit/test-bdrv-graph-mod.c index 7b03ebe4b0..b077f0e3e3 100644 --- a/tests/unit/test-bdrv-graph-mod.c +++ b/tests/unit/test-bdrv-graph-mod.c @@ -137,12 +137,10 @@ static void test_update_perm_tree(void) blk_insert_bs(root, bs, &error_abort); - bdrv_drain_all_begin(); - bdrv_graph_wrlock(); + bdrv_graph_wrlock_drained(); bdrv_attach_child(filter, bs, "child", &child_of_bds, BDRV_CHILD_DATA, &error_abort); bdrv_graph_wrunlock(); - bdrv_drain_all_end(); ret = bdrv_append(filter, bs, NULL); g_assert_cmpint(ret, <, 0); @@ -206,13 +204,11 @@ static void test_should_update_child(void) bdrv_set_backing_hd(target, bs, &error_abort); - bdrv_drain_all_begin(); - bdrv_graph_wrlock(); + bdrv_graph_wrlock_drained(); g_assert(target->backing->bs == bs); bdrv_attach_child(filter, target, "target", &child_of_bds, BDRV_CHILD_DATA, &error_abort); bdrv_graph_wrunlock(); - bdrv_drain_all_end(); bdrv_append(filter, bs, &error_abort); bdrv_graph_rdlock_main_loop(); @@ -248,8 +244,7 @@ static void test_parallel_exclusive_write(void) bdrv_ref(base); bdrv_ref(fl1); - bdrv_drain_all_begin(); - bdrv_graph_wrlock(); + bdrv_graph_wrlock_drained(); bdrv_attach_child(top, fl1, "backing", &child_of_bds, BDRV_CHILD_FILTERED | BDRV_CHILD_PRIMARY, &error_abort); @@ -262,7 +257,6 @@ static void test_parallel_exclusive_write(void) bdrv_replace_node(fl1, fl2, &error_abort); bdrv_graph_wrunlock(); - bdrv_drain_all_end(); bdrv_drained_end(fl2); bdrv_drained_end(fl1); @@ -369,8 +363,7 @@ static void test_parallel_perm_update(void) */ bdrv_ref(base); - bdrv_drain_all_begin(); - bdrv_graph_wrlock(); + bdrv_graph_wrlock_drained(); bdrv_attach_child(top, ws, "file", &child_of_bds, BDRV_CHILD_DATA, &error_abort); c_fl1 = bdrv_attach_child(ws, fl1, "first", &child_of_bds, @@ -384,7 +377,6 @@ static void test_parallel_perm_update(void) BDRV_CHILD_FILTERED | BDRV_CHILD_PRIMARY, &error_abort); bdrv_graph_wrunlock(); - bdrv_drain_all_end(); /* Select fl1 as first child to be active */ s->selected = c_fl1; @@ -438,13 +430,11 @@ static void test_append_greedy_filter(void) BlockDriverState *base = no_perm_node("base"); BlockDriverState *fl = exclusive_writer_node("fl1"); - bdrv_drain_all_begin(); - bdrv_graph_wrlock(); + bdrv_graph_wrlock_drained(); bdrv_attach_child(top, base, "backing", &child_of_bds, BDRV_CHILD_FILTERED | BDRV_CHILD_PRIMARY, &error_abort); bdrv_graph_wrunlock(); - bdrv_drain_all_end(); bdrv_append(fl, base, &error_abort); bdrv_unref(fl); -- 2.39.5