From: Barry Song <v-songbaohua@xxxxxxxx> The code is quite hard to read, we are still writing swap_map after errors happen. Though the written value is as before, has_cache = count & SWAP_HAS_CACHE; count &= ~SWAP_HAS_CACHE; [snipped] WRITE_ONCE(p->swap_map[offset], count | has_cache); It would be better to entirely drop the WRITE_ONCE for both performance and readability. Signed-off-by: Barry Song <v-songbaohua@xxxxxxxx> --- mm/swapfile.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/mm/swapfile.c b/mm/swapfile.c index 556ff7347d5f..17557003858c 100644 --- a/mm/swapfile.c +++ b/mm/swapfile.c @@ -3320,6 +3320,9 @@ static int __swap_duplicate(swp_entry_t entry, unsigned char usage) } else err = -ENOENT; /* unused swap entry */ + if (err) + goto unlock_out; + WRITE_ONCE(p->swap_map[offset], count | has_cache); unlock_out: -- 2.34.1
