diff options
| author | Barry Song <v-songbaohua@oppo.com> | 2024-02-20 10:19:35 +1300 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2024-02-23 17:48:31 -0800 |
| commit | 55e78c933d747ed44b2b22879e6a55e5af34b9f7 (patch) | |
| tree | 785436d62939bded2689efaf961e38aa65c16180 /mm | |
| parent | 929e4c3534ecdc6c11921dff5a54597c5d61ca6a (diff) | |
| download | linux-55e78c933d747ed44b2b22879e6a55e5af34b9f7.tar.gz | |
mm: zswap: increase reject_compress_poor but not reject_compress_fail if compression returns ENOSPC
We used to rely on the returned -ENOSPC of zpool_malloc() to increase
reject_compress_poor. But the code wouldn't get to there after commit
744e1885922a ("crypto: scomp - fix req->dst buffer overflow") as the new
code will goto out immediately after the special compression case happens.
So there might be no longer a chance to execute zpool_malloc now. We are
incorrectly increasing zswap_reject_compress_fail instead. Thus, we need
to fix the counters handling right after compressions return ENOSPC. This
patch also centralizes the counters handling for all of compress_poor,
compress_fail and alloc_fail.
Link: https://lkml.kernel.org/r/20240219211935.72394-1-21cnbao@gmail.com
Fixes: 744e1885922a ("crypto: scomp - fix req->dst buffer overflow")
Signed-off-by: Barry Song <v-songbaohua@oppo.com>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
Reviewed-by: Nhat Pham <nphamcs@gmail.com>
Acked-by: Yosry Ahmed <yosryahmed@google.com>
Reviewed-by: Chengming Zhou <zhouchengming@bytedance.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Diffstat (limited to 'mm')
| -rw-r--r-- | mm/zswap.c | 27 |
1 files changed, 13 insertions, 14 deletions
diff --git a/mm/zswap.c b/mm/zswap.c index 62fe307521c937..51de79aa86593d 100644 --- a/mm/zswap.c +++ b/mm/zswap.c @@ -1021,12 +1021,12 @@ static bool zswap_compress(struct folio *folio, struct zswap_entry *entry) { struct crypto_acomp_ctx *acomp_ctx; struct scatterlist input, output; + int comp_ret = 0, alloc_ret = 0; unsigned int dlen = PAGE_SIZE; unsigned long handle; struct zpool *zpool; char *buf; gfp_t gfp; - int ret; u8 *dst; acomp_ctx = raw_cpu_ptr(entry->pool->acomp_ctx); @@ -1057,26 +1057,18 @@ static bool zswap_compress(struct folio *folio, struct zswap_entry *entry) * but in different threads running on different cpu, we have different * acomp instance, so multiple threads can do (de)compression in parallel. */ - ret = crypto_wait_req(crypto_acomp_compress(acomp_ctx->req), &acomp_ctx->wait); + comp_ret = crypto_wait_req(crypto_acomp_compress(acomp_ctx->req), &acomp_ctx->wait); dlen = acomp_ctx->req->dlen; - if (ret) { - zswap_reject_compress_fail++; + if (comp_ret) goto unlock; - } zpool = zswap_find_zpool(entry); gfp = __GFP_NORETRY | __GFP_NOWARN | __GFP_KSWAPD_RECLAIM; if (zpool_malloc_support_movable(zpool)) gfp |= __GFP_HIGHMEM | __GFP_MOVABLE; - ret = zpool_malloc(zpool, dlen, gfp, &handle); - if (ret == -ENOSPC) { - zswap_reject_compress_poor++; - goto unlock; - } - if (ret) { - zswap_reject_alloc_fail++; + alloc_ret = zpool_malloc(zpool, dlen, gfp, &handle); + if (alloc_ret) goto unlock; - } buf = zpool_map_handle(zpool, handle, ZPOOL_MM_WO); memcpy(buf, dst, dlen); @@ -1086,8 +1078,15 @@ static bool zswap_compress(struct folio *folio, struct zswap_entry *entry) entry->length = dlen; unlock: + if (comp_ret == -ENOSPC || alloc_ret == -ENOSPC) + zswap_reject_compress_poor++; + else if (comp_ret) + zswap_reject_compress_fail++; + else if (alloc_ret) + zswap_reject_alloc_fail++; + mutex_unlock(&acomp_ctx->mutex); - return ret == 0; + return comp_ret == 0 && alloc_ret == 0; } static void zswap_decompress(struct zswap_entry *entry, struct page *page) |