| Message ID | 20240124045113.415378-3-yosryahmed@google.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | mm: zswap: simplify zswap_swapoff() | expand |
On Tue, Jan 23, 2024 at 8:51 PM Yosry Ahmed <yosryahmed@google.com> wrote: > > 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. > > Signed-off-by: Yosry Ahmed <yosryahmed@google.com> Johannes, Nhat, I didn't carry the Acks forward after the rebase as the code changed significantly.
On 2024/1/24 12:51, Yosry Ahmed wrote: > 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. > > Signed-off-by: Yosry Ahmed <yosryahmed@google.com> Looks good to me, thanks! Reviewed-by: Chengming Zhou <zhouchengming@bytedance.com> > --- > mm/zswap.c | 16 +++------------- > 1 file changed, 3 insertions(+), 13 deletions(-) > > diff --git a/mm/zswap.c b/mm/zswap.c > index dcdd5ecfedb09..78df16d307aa8 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;
diff --git a/mm/zswap.c b/mm/zswap.c index dcdd5ecfedb09..78df16d307aa8 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;
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. Signed-off-by: Yosry Ahmed <yosryahmed@google.com> --- mm/zswap.c | 16 +++------------- 1 file changed, 3 insertions(+), 13 deletions(-)