On 2024/1/30 09:36, Johannes Weiner wrote:
> - Remove dupentry, reusing entry works just fine.
> - Rename pool to shrink_pool, as this one actually is confusing.
> - Remove page, use folio_nid() and kmap_local_folio() directly.
> - Set entry->swpentry in a common path.
> - Move value and src to local scope of use.
>
> Signed-off-by: Johannes Weiner <hannes@xxxxxxxxxxx>
Reviewed-by: Chengming Zhou <zhouchengming@xxxxxxxxxxxxx>
> ---
> mm/zswap.c | 28 +++++++++++++---------------
> 1 file changed, 13 insertions(+), 15 deletions(-)
>
> diff --git a/mm/zswap.c b/mm/zswap.c
> index f9b9494156ba..cde309c539b3 100644
> --- a/mm/zswap.c
> +++ b/mm/zswap.c
> @@ -1542,14 +1542,11 @@ bool zswap_store(struct folio *folio)
> {
> swp_entry_t swp = folio->swap;
> pgoff_t offset = swp_offset(swp);
> - struct page *page = &folio->page;
> struct zswap_tree *tree = swap_zswap_tree(swp);
> struct zswap_entry *entry, *dupentry;
> struct obj_cgroup *objcg = NULL;
> struct mem_cgroup *memcg = NULL;
> - struct zswap_pool *pool;
> - unsigned long value;
> - u8 *src;
> + struct zswap_pool *shrink_pool;
>
> VM_WARN_ON_ONCE(!folio_test_locked(folio));
> VM_WARN_ON_ONCE(!folio_test_swapcache(folio));
> @@ -1567,10 +1564,10 @@ bool zswap_store(struct folio *folio)
> * the tree, and it might be written back overriding the new data.
> */
> spin_lock(&tree->lock);
> - dupentry = zswap_rb_search(&tree->rbroot, offset);
> - if (dupentry) {
> + entry = zswap_rb_search(&tree->rbroot, offset);
> + if (entry) {
> + zswap_invalidate_entry(tree, entry);
> zswap_duplicate_entry++;
> - zswap_invalidate_entry(tree, dupentry);
> }
> spin_unlock(&tree->lock);
> objcg = get_obj_cgroup_from_folio(folio);
> @@ -1598,17 +1595,19 @@ bool zswap_store(struct folio *folio)
> }
>
> /* allocate entry */
> - entry = zswap_entry_cache_alloc(GFP_KERNEL, page_to_nid(page));
> + entry = zswap_entry_cache_alloc(GFP_KERNEL, folio_nid(folio));
> if (!entry) {
> zswap_reject_kmemcache_fail++;
> goto reject;
> }
>
> if (zswap_same_filled_pages_enabled) {
> - src = kmap_local_page(page);
> + unsigned long value;
> + u8 *src;
> +
> + src = kmap_local_folio(folio, 0);
> if (zswap_is_page_same_filled(src, &value)) {
> kunmap_local(src);
> - entry->swpentry = swp;
> entry->length = 0;
> entry->value = value;
> atomic_inc(&zswap_same_filled_pages);
> @@ -1637,9 +1636,8 @@ bool zswap_store(struct folio *folio)
> if (!zswap_compress(folio, entry))
> goto put_pool;
>
> - entry->swpentry = swp;
> -
> insert_entry:
> + entry->swpentry = swp;
> entry->objcg = objcg;
> if (objcg) {
> obj_cgroup_charge_zswap(objcg, entry->length);
> @@ -1684,9 +1682,9 @@ bool zswap_store(struct folio *folio)
> return false;
>
> shrink:
> - pool = zswap_pool_last_get();
> - if (pool && !queue_work(shrink_wq, &pool->shrink_work))
> - zswap_pool_put(pool);
> + shrink_pool = zswap_pool_last_get();
> + if (shrink_pool && !queue_work(shrink_wq, &shrink_pool->shrink_work))
> + zswap_pool_put(shrink_pool);
> goto reject;
> }
>
