From fa055ddfd5853ab4102bb189e79bb24648291df3 Mon Sep 17 00:00:00 2001 From: Jaegeuk Kim Date: Mon, 13 Dec 2021 13:28:40 -0800 Subject: [PATCH] BACKPORT: f2fs: avoid down_write on nat_tree_lock during checkpoint Let's cache nat entry if there's no lock contention only. Bug: 214413989 Reviewed-by: Chao Yu Signed-off-by: Jaegeuk Kim (cherry picked from commit 0df035c7208c5e3e2ae7685548353ae536a19015 git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master) [ Address merge conflict ] Change-Id: I0bf70451bc0b148ebb88429d6294ea8e68008e48 --- fs/f2fs/node.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/fs/f2fs/node.c b/fs/f2fs/node.c index 28cfc9a86010..52a030e8181d 100644 --- a/fs/f2fs/node.c +++ b/fs/f2fs/node.c @@ -428,6 +428,10 @@ static void cache_nat_entry(struct f2fs_sb_info *sbi, nid_t nid, struct f2fs_nm_info *nm_i = NM_I(sbi); struct nat_entry *new, *e; + /* Let's mitigate lock contention of nat_tree_lock during checkpoint */ + if (rwsem_is_locked(&sbi->cp_global_sem)) + return; + new = __alloc_nat_entry(nid, false); if (!new) return;