From 6b89e851fabf78d7fb090bcdc71789ea1ef55c9b Mon Sep 17 00:00:00 2001 From: Fiona Ebner Date: Fri, 30 May 2025 17:11:01 +0200 Subject: block: add bdrv_graph_wrlock_drained() convenience wrapper Many write-locked 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. Since the wrapper calls bdrv_drain_all_begin(), which must be called with the graph unlocked, mark the wrapper as GRAPH_UNLOCKED too. 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 Signed-off-by: Fiona Ebner Message-ID: <20250530151125.955508-25-f.ebner@proxmox.com> [kwolf: Removed redundant GRAPH_UNLOCKED] Reviewed-by: Kevin Wolf Signed-off-by: Kevin Wolf --- tests/unit/test-bdrv-graph-mod.c | 20 +++++--------------- 1 file changed, 5 insertions(+), 15 deletions(-) (limited to 'tests/unit/test-bdrv-graph-mod.c') 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); -- cgit 1.4.1