From nobody Sat Dec 27 18:56:00 2025 Received: from out-185.mta0.migadu.com (out-185.mta0.migadu.com [91.218.175.185]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 87C27381CD for ; Mon, 18 Dec 2023 11:50:52 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dmarc=fail (p=quarantine dis=none) header.from=bytedance.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. From: Chengming Zhou Date: Mon, 18 Dec 2023 11:50:35 +0000 Subject: [PATCH v3 5/6] mm/zswap: cleanup zswap_writeback_entry() Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Message-Id: <20231213-zswap-dstmem-v3-5-4eac09b94ece@bytedance.com> References: <20231213-zswap-dstmem-v3-0-4eac09b94ece@bytedance.com> In-Reply-To: <20231213-zswap-dstmem-v3-0-4eac09b94ece@bytedance.com> To: Seth Jennings , Yosry Ahmed , Vitaly Wool , Dan Streetman , Johannes Weiner , Chris Li , Andrew Morton , Nhat Pham Cc: Chris Li , Yosry Ahmed , linux-kernel@vger.kernel.org, Chengming Zhou , linux-mm@kvack.org, Nhat Pham X-Developer-Signature: v=1; a=ed25519-sha256; t=1702900234; l=2215; i=zhouchengming@bytedance.com; s=20231204; h=from:subject:message-id; bh=u9D8B3ksO9G67avNjANTAO3qS+/SASwDD1QW2eXuPmA=; b=bX9QDtAp6LhqXJx8Yr0LWdcF0z06lztvYdnRzlwugcBS4LaRmP3c9JNAMHRIFxNxSVfv4KXJP 2yn6oW6AM20DLSOlXaQvsN42SgrRlNXTLt3ZWYzqDYQTNtDhy74I4xe X-Developer-Key: i=zhouchengming@bytedance.com; a=ed25519; pk=xFTmRtMG3vELGJBUiml7OYNdM393WOMv0iWWeQEVVdA= X-Migadu-Flow: FLOW_OUT Also after the common decompress part goes to __zswap_load(), we can cleanup the zswap_writeback_entry() a little. Reviewed-by: Yosry Ahmed Reviewed-by: Nhat Pham Signed-off-by: Chengming Zhou Acked-by: Chris Li (Google) --- mm/zswap.c | 25 +++++++++---------------- 1 file changed, 9 insertions(+), 16 deletions(-) diff --git a/mm/zswap.c b/mm/zswap.c index 86886276cb81..2c349fd88904 100644 --- a/mm/zswap.c +++ b/mm/zswap.c @@ -1443,7 +1443,6 @@ 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 =3D { .sync_mode =3D WB_SYNC_NONE, }; @@ -1453,15 +1452,18 @@ static int zswap_writeback_entry(struct zswap_entry= *entry, page =3D __read_swap_cache_async(swpentry, GFP_KERNEL, mpol, NO_INTERLEAVE_INDEX, &page_was_allocated, true); if (!page) { - ret =3D -ENOMEM; - goto 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 -ENOMEM; } =20 /* Found an existing page, we raced with load/swapin */ if (!page_was_allocated) { put_page(page); - ret =3D -EEXIST; - goto fail; + return -EEXIST; } =20 /* @@ -1475,8 +1477,7 @@ static int zswap_writeback_entry(struct zswap_entry *= entry, if (zswap_rb_search(&tree->rbroot, swp_offset(entry->swpentry)) !=3D entr= y) { spin_unlock(&tree->lock); delete_from_swap_cache(page_folio(page)); - ret =3D -ENOMEM; - goto fail; + return -ENOMEM; } spin_unlock(&tree->lock); =20 @@ -1497,15 +1498,7 @@ static int zswap_writeback_entry(struct zswap_entry = *entry, __swap_writepage(page, &wbc); put_page(page); =20 - 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; } =20 static int zswap_is_page_same_filled(void *ptr, unsigned long *value) --=20 b4 0.10.1