From 83e68f25decdc8d133dbfedd18b93f5267430049 Mon Sep 17 00:00:00 2001 From: Yosry Ahmed Date: Wed, 24 Jan 2024 04:51:12 +0000 Subject: [PATCH] mm: zswap: remove unnecessary trees cleanups in zswap_swapoff() During swapoff, try_to_unuse() makes sure that zswap_invalidate() is called for all swap entries before zswap_swapoff() is called. This means that all zswap entries should already be removed from the tree. Simplify zswap_swapoff() by removing the trees cleanup code, and leave an assertion in its place. Link: https://lkml.kernel.org/r/20240124045113.415378-3-yosryahmed@google.com Signed-off-by: Yosry Ahmed Reviewed-by: Chengming Zhou Cc: Chris Li Cc: "Huang, Ying" Cc: Johannes Weiner Cc: Nhat Pham Signed-off-by: Andrew Morton --- mm/zswap.c | 16 +++------------- 1 file changed, 3 insertions(+), 13 deletions(-) diff --git a/mm/zswap.c b/mm/zswap.c index 464179d43399..0e4a869b6fd8 100644 --- a/mm/zswap.c +++ b/mm/zswap.c @@ -1808,19 +1808,9 @@ void zswap_swapoff(int type) if (!trees) return; - for (i = 0; i < nr_zswap_trees[type]; i++) { - struct zswap_tree *tree = trees + i; - struct zswap_entry *entry, *n; - - /* walk the tree and free everything */ - spin_lock(&tree->lock); - rbtree_postorder_for_each_entry_safe(entry, n, - &tree->rbroot, - rbnode) - zswap_free_entry(entry); - tree->rbroot = RB_ROOT; - spin_unlock(&tree->lock); - } + /* try_to_unuse() invalidated all the entries already */ + for (i = 0; i < nr_zswap_trees[type]; i++) + WARN_ON_ONCE(!RB_EMPTY_ROOT(&trees[i].rbroot)); kvfree(trees); nr_zswap_trees[type] = 0;