summaryrefslogtreecommitdiffstats
path: root/fs/f2fs
diff options
context:
space:
mode:
authorChao Yu <chao2.yu@samsung.com>2016-02-26 09:33:04 +0800
committerJaegeuk Kim <jaegeuk@kernel.org>2016-02-26 11:52:03 -0800
commit19c7377b56a618c2a6ae1dfef1c22f19ad9d427c (patch)
tree401ffa888a214a430e2b39e7eba259014d5dca5b /fs/f2fs
parent406657dd1868a4d7b12be04ed769d9215ec9a7d1 (diff)
downloadlinux-stable-19c7377b56a618c2a6ae1dfef1c22f19ad9d427c.tar.gz
linux-stable-19c7377b56a618c2a6ae1dfef1c22f19ad9d427c.tar.bz2
linux-stable-19c7377b56a618c2a6ae1dfef1c22f19ad9d427c.zip
f2fs: fix to avoid deadlock when merging inline data
When testing with fsstress, kworker and user threads were both blocked: INFO: task kworker/u16:1:16580 blocked for more than 120 seconds. "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/u16:1 D ffff8803f2595390 0 16580 2 0x00000000 Workqueue: writeback bdi_writeback_workfn (flush-251:0) ffff8802730e5760 0000000000000046 ffff880274729fc0 0000000000012440 ffff8802730e5fd8 ffff8802730e4010 0000000000012440 0000000000012440 ffff8802730e5fd8 0000000000012440 ffff880274729fc0 ffff88026eb50000 Call Trace: [<ffffffff816fe9d9>] schedule+0x29/0x70 [<ffffffff816ff895>] rwsem_down_read_failed+0xa5/0xf9 [<ffffffff81378584>] call_rwsem_down_read_failed+0x14/0x30 [<ffffffffa0694feb>] f2fs_write_data_page+0x31b/0x420 [f2fs] [<ffffffffa0690f1a>] __f2fs_writepage+0x1a/0x50 [f2fs] [<ffffffffa06922a0>] f2fs_write_data_pages+0xe0/0x290 [f2fs] [<ffffffff811473b3>] do_writepages+0x23/0x40 [<ffffffff811cc3ee>] __writeback_single_inode+0x4e/0x250 [<ffffffff811cd4f1>] writeback_sb_inodes+0x2c1/0x470 [<ffffffff811cd73e>] __writeback_inodes_wb+0x9e/0xd0 [<ffffffff811cda0b>] wb_writeback+0x1fb/0x2d0 [<ffffffff811cdb7c>] wb_do_writeback+0x9c/0x220 [<ffffffff811ce232>] bdi_writeback_workfn+0x72/0x1c0 [<ffffffff8106b74e>] process_one_work+0x1de/0x5b0 [<ffffffff8106e78f>] worker_thread+0x11f/0x3e0 [<ffffffff810750ce>] kthread+0xde/0xf0 [<ffffffff817093f8>] ret_from_fork+0x58/0x90 fsstress thread stack: [<ffffffff81139f0e>] sleep_on_page+0xe/0x20 [<ffffffff81139ef7>] __lock_page+0x67/0x70 [<ffffffff8113b100>] find_lock_page+0x50/0x80 [<ffffffff8113b24f>] find_or_create_page+0x3f/0xb0 [<ffffffffa06983a9>] sync_node_pages+0x259/0x810 [f2fs] [<ffffffffa068d874>] write_checkpoint+0x1a4/0xce0 [f2fs] [<ffffffffa0686b0c>] f2fs_sync_fs+0x7c/0xd0 [f2fs] [<ffffffffa067c813>] f2fs_sync_file+0x143/0x5f0 [f2fs] [<ffffffff811d301b>] vfs_fsync_range+0x2b/0x40 [<ffffffff811d304c>] vfs_fsync+0x1c/0x20 [<ffffffff811d3291>] do_fsync+0x41/0x70 [<ffffffff811d32d3>] SyS_fdatasync+0x13/0x20 [<ffffffff817094a2>] system_call_fastpath+0x16/0x1b [<ffffffffffffffff>] 0xffffffffffffffff The reason of this issue is: CPU0: CPU1: - f2fs_write_data_pages - f2fs_sync_fs - write_checkpoint - block_operations - f2fs_lock_all - down_write(sbi->cp_rwsem) - lock_page(page) - f2fs_write_data_page - sync_node_pages - flush_inline_data - pagecache_get_page(page, GFP_LOCK) - f2fs_lock_op - down_read(sbi->cp_rwsem) This patch alters to use trylock_page in flush_inline_data to fix this ABBA deadlock issue. Signed-off-by: Chao Yu <chao2.yu@samsung.com> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Diffstat (limited to 'fs/f2fs')
-rw-r--r--fs/f2fs/node.c9
1 files changed, 7 insertions, 2 deletions
diff --git a/fs/f2fs/node.c b/fs/f2fs/node.c
index 7b613dd16e77..d714b607bf46 100644
--- a/fs/f2fs/node.c
+++ b/fs/f2fs/node.c
@@ -1203,10 +1203,13 @@ static void flush_inline_data(struct f2fs_sb_info *sbi, nid_t ino)
if (!inode)
return;
- page = pagecache_get_page(inode->i_mapping, 0, FGP_LOCK|FGP_NOWAIT, 0);
+ page = pagecache_get_page(inode->i_mapping, 0, FGP_NOWAIT, 0);
if (!page)
goto iput_out;
+ if (!trylock_page(page))
+ goto release_out;
+
if (!PageUptodate(page))
goto page_out;
@@ -1221,7 +1224,9 @@ static void flush_inline_data(struct f2fs_sb_info *sbi, nid_t ino)
else
set_page_dirty(page);
page_out:
- f2fs_put_page(page, 1);
+ unlock_page(page);
+release_out:
+ f2fs_put_page(page, 0);
iput_out:
iput(inode);
}