lkml.org 
[lkml]   [2022]   [Nov]   [16]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH v5 1/2] btrfs: add might_sleep() to btrfs_search_slot()
Date
At least 2 places might sleep in btrfs_search_slot(), as shown below:

btrfs_search_slot
setup_nodes_for_search
reada_for_balance
btrfs_readahead_node_child
btrfs_readahead_tree_block
btrfs_find_create_tree_block
alloc_extent_buffer
kmem_cache_zalloc
/* allocate memory non-atomically, might sleep */
kmem_cache_alloc(GFP_NOFS|__GFP_NOFAIL|__GFP_ZERO)
read_extent_buffer_pages
submit_extent_page
/* disk IO, might sleep */
submit_one_bio

As the potential sleeping under spin lock is hard to spot, we should add
might_sleep() to btrfs_search_slot().

Signed-off-by: ChenXiaoSong <chenxiaosong2@huawei.com>
---
fs/btrfs/ctree.c | 2 ++
1 file changed, 2 insertions(+)

diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c
index a9543f01184c..809053e9cfde 100644
--- a/fs/btrfs/ctree.c
+++ b/fs/btrfs/ctree.c
@@ -1934,6 +1934,8 @@ int btrfs_search_slot(struct btrfs_trans_handle *trans, struct btrfs_root *root,
int min_write_lock_level;
int prev_cmp;

+ might_sleep();
+
lowest_level = p->lowest_level;
WARN_ON(lowest_level && ins_len > 0);
WARN_ON(p->nodes[0] != NULL);
--
2.31.1
\
 
 \ /
  Last update: 2022-11-16 13:10    [W:0.121 / U:0.084 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site