commit 6ec75a6a3ed9d6ff3161d1f97c497909906495bd
author Kevin Wolf <kwolf@redhat.com> Thu May 04 13:57:47 2023 +0200
committer Kevin Wolf <kwolf@redhat.com> Wed May 10 14:16:54 2023 +0200
tree ff7f5cf2b54197a81c4d13402134e57a8be7b08a
parent 840428a2669c90f75cf0d26a06bdfe6f51755fae

block: Mark bdrv_query_bds_stats() and callers GRAPH_RDLOCK

This adds GRAPH_RDLOCK annotations to declare that callers of
bdrv_query_bds_stats() need to hold a reader lock for the graph because
it accesses the children list of a node.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20230504115750.54437-18-kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

block/qapi.c

diff --git a/block/qapi.c b/block/qapi.c
index c841478..71f2751 100644
--- a/block/qapi.c
+++ b/block/qapi.c
@@ -604,8 +604,8 @@
         = bdrv_latency_histogram_stats(&hgram[BLOCK_ACCT_FLUSH]);
 }
 
-static BlockStats *bdrv_query_bds_stats(BlockDriverState *bs,
-                                        bool blk_level)
+static BlockStats * GRAPH_RDLOCK
+bdrv_query_bds_stats(BlockDriverState *bs, bool blk_level)
 {
     BdrvChild *parent_child;
     BlockDriverState *filter_or_cow_bs;
@@ -713,6 +713,8 @@
     BlockBackend *blk;
     BlockDriverState *bs;
 
+    GRAPH_RDLOCK_GUARD_MAINLOOP();
+
     /* Just to be safe if query_nodes is not always initialized */
     if (has_query_nodes && query_nodes) {
         for (bs = bdrv_next_node(NULL); bs; bs = bdrv_next_node(bs)) {