Hi Sayali, In order to address the perf regression, how about this?
>From 48418af635884803ffb35972df7958a2e6649322 Mon Sep 17 00:00:00 2001 From: Jaegeuk Kim <[email protected]> Date: Fri, 8 May 2020 09:08:37 -0700 Subject: [PATCH] f2fs: avoid double lock for cp_rwsem during checkpoint There could be a scenario where f2fs_sync_node_pages gets called during checkpoint, which in turn tries to flush inline data and calls iput(). This results in deadlock as iput() tries to hold cp_rwsem, which is already held at the beginning by checkpoint->block_operations(). Call stack : Thread A Thread B f2fs_write_checkpoint() - block_operations(sbi) - f2fs_lock_all(sbi); - down_write(&sbi->cp_rwsem); - open() - igrab() - write() write inline data - unlink() - f2fs_sync_node_pages() - if (is_inline_node(page)) - flush_inline_data() - ilookup() page = f2fs_pagecache_get_page() if (!page) goto iput_out; iput_out: -close() -iput() iput(inode); - f2fs_evict_inode() - f2fs_truncate_blocks() - f2fs_lock_op() - down_read(&sbi->cp_rwsem); Fixes: 2049d4fcb057 ("f2fs: avoid multiple node page writes due to inline_data") Signed-off-by: Sayali Lokhande <[email protected]> Signed-off-by: Jaegeuk Kim <[email protected]> --- fs/f2fs/node.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/fs/f2fs/node.c b/fs/f2fs/node.c index 1db8cabf727ef..626d7daca09de 100644 --- a/fs/f2fs/node.c +++ b/fs/f2fs/node.c @@ -1870,8 +1870,8 @@ int f2fs_sync_node_pages(struct f2fs_sb_info *sbi, goto continue_unlock; } - /* flush inline_data */ - if (is_inline_node(page)) { + /* flush inline_data, if it's not sync path. */ + if (do_balance && is_inline_node(page)) { clear_inline_node(page); unlock_page(page); flush_inline_data(sbi, ino_of_node(page)); -- 2.26.2.645.ge9eca65c58-goog
