diff options
| author | Chengming Zhou <zhouchengming@bytedance.com> | 2023-12-28 09:45:45 +0000 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2023-12-29 11:58:29 -0800 |
| commit | e947ba0bbf470fb3d813383426bdcd3c88fe9a7b (patch) | |
| tree | c75835b7a835ecdf4a7070396009c7b5a6edce97 | |
| parent | 66447fd036a5a540bef67a96b770d4ed84ad0467 (diff) | |
mm/zswap: cleanup zswap_writeback_entry()
Also after the common decompress part goes to __zswap_load(), we can
cleanup the zswap_writeback_entry() a little.
Link: https://lkml.kernel.org/r/20231213-zswap-dstmem-v5-4-9382162bbf05@bytedance.com
Signed-off-by: Chengming Zhou <zhouchengming@bytedance.com>
Reviewed-by: Yosry Ahmed <yosryahmed@google.com>
Reviewed-by: Nhat Pham <nphamcs@gmail.com>
Acked-by: Chris Li <chrisl@kernel.org> (Google)
Cc: Barry Song <21cnbao@gmail.com>
Cc: Dan Streetman <ddstreet@ieee.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Seth Jennings <sjenning@redhat.com>
Cc: Vitaly Wool <vitaly.wool@konsulko.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
| -rw-r--r-- | mm/zswap.c | 29 |
1 files changed, 10 insertions, 19 deletions
diff --git a/mm/zswap.c b/mm/zswap.c index d8e883b52cb7..880c33bbe146 100644 --- a/mm/zswap.c +++ b/mm/zswap.c @@ -1434,7 +1434,6 @@ static int zswap_writeback_entry(struct zswap_entry *entry, struct page *page; struct mempolicy *mpol; bool page_was_allocated; - int ret; struct writeback_control wbc = { .sync_mode = WB_SYNC_NONE, }; @@ -1443,16 +1442,17 @@ static int zswap_writeback_entry(struct zswap_entry *entry, mpol = get_task_policy(current); page = __read_swap_cache_async(swpentry, GFP_KERNEL, mpol, NO_INTERLEAVE_INDEX, &page_was_allocated, true); - if (!page) { - ret = -ENOMEM; - goto fail; - } + if (!page) + return -ENOMEM; - /* Found an existing page, we raced with load/swapin */ + /* + * Found an existing page, we raced with load/swapin. We generally + * writeback cold pages from zswap, and swapin means the page just + * became hot. Skip this page and let the caller find another one. + */ if (!page_was_allocated) { put_page(page); - ret = -EEXIST; - goto fail; + return -EEXIST; } /* @@ -1466,8 +1466,7 @@ static int zswap_writeback_entry(struct zswap_entry *entry, if (zswap_rb_search(&tree->rbroot, swp_offset(entry->swpentry)) != entry) { spin_unlock(&tree->lock); delete_from_swap_cache(page_folio(page)); - ret = -ENOMEM; - goto fail; + return -ENOMEM; } spin_unlock(&tree->lock); @@ -1483,15 +1482,7 @@ static int zswap_writeback_entry(struct zswap_entry *entry, __swap_writepage(page, &wbc); put_page(page); - return ret; - -fail: - /* - * If we get here because the page is already in swapcache, a - * load may be happening concurrently. It is safe and okay to - * not free the entry. It is also okay to return !0. - */ - return ret; + return 0; } static int zswap_is_page_same_filled(void *ptr, unsigned long *value) |