From nobody Wed Dec 17 03:04:19 2025 Received: from out30-112.freemail.mail.aliyun.com (out30-112.freemail.mail.aliyun.com [115.124.30.112]) (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 0490515C12B for ; Mon, 12 Aug 2024 07:42:29 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=115.124.30.112 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1723448553; cv=none; b=QUMFd9umFWWPTD+8RkyeFnFCTors05ARKCmvFo1iTAawQCsRIwzsirmQ69alUjjkzzjRpB+sAueLvJgx92mBdMQSOEw3xQVRkp+h9K7a+oHadcrs5ISuISiq9nXUbiMXWt5m3rRGXW8upNRxD6D7JhSzhvjM4/FFTBf2cnmRchg= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1723448553; c=relaxed/simple; bh=wU+mvmFmyXxD/VfwSu8JkQrOHqzi5LfMKdgy7Mj74U4=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=kbSyRxns24bf5sSw/LMQJ6Qx5KiFNQ1rAvht4fovc8FolHI+1AlUIkW3mHJevovZnsv0fQpnX25d4GW5vfMbybQ9lEzXzyTV/Is7VOu7su7EVSh/hjJvsgD7Dw3GXeN2nu4tiw6lOVd7RE7Ad2Ky0RI9d9+Jpufap1IJBgJG1n0= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.alibaba.com; spf=pass smtp.mailfrom=linux.alibaba.com; dkim=pass (1024-bit key) header.d=linux.alibaba.com header.i=@linux.alibaba.com header.b=tU8ArFSW; arc=none smtp.client-ip=115.124.30.112 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.alibaba.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.alibaba.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.alibaba.com header.i=@linux.alibaba.com header.b="tU8ArFSW" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.alibaba.com; s=default; t=1723448542; h=From:To:Subject:Date:Message-Id:MIME-Version; bh=71u6PF0T766CyIr04AjwEpJvSI8v+1Ntw3LK3owxVuQ=; b=tU8ArFSWaw0R/n1rHBU30YyW2KKq4GhtVbV10IOgZ6nenZ0Q4CYRtGJpd/VYSErwu6tVLLA2Vp7fuCq0zFgwAWp5iOE0xYl/fkB2WB92SYf9Mg4VzpRd41rmQU8+6PyZMzm2dk+jllh5GViOiIWE2FlT1+m4yrJx6qTF/bsq8e8= Received: from localhost(mailfrom:baolin.wang@linux.alibaba.com fp:SMTPD_---0WCbAKOu_1723448540) by smtp.aliyun-inc.com; Mon, 12 Aug 2024 15:42:21 +0800 From: Baolin Wang To: akpm@linux-foundation.org, hughd@google.com Cc: willy@infradead.org, david@redhat.com, wangkefeng.wang@huawei.com, chrisl@kernel.org, ying.huang@intel.com, 21cnbao@gmail.com, ryan.roberts@arm.com, shy828301@gmail.com, ziy@nvidia.com, ioworker0@gmail.com, da.gomez@samsung.com, p.raghav@samsung.com, baolin.wang@linux.alibaba.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: [PATCH v5 3/9] mm: shmem: return number of pages beeing freed in shmem_free_swap Date: Mon, 12 Aug 2024 15:42:04 +0800 Message-Id: <9623e863c83d749d5ab407f6fdf0a8e5a3bdf052.1723434324.git.baolin.wang@linux.alibaba.com> X-Mailer: git-send-email 2.39.3 In-Reply-To: References: Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" From: Daniel Gomez Both shmem_free_swap callers expect the number of pages being freed. In the large folios context, this needs to support larger values other than 0 (used as 1 page being freed) and -ENOENT (used as 0 pages being freed). In preparation for large folios adoption, make shmem_free_swap routine return the number of pages being freed. So, returning 0 in this context, means 0 pages being freed. While we are at it, changing to use free_swap_and_cache_nr() to free large order swap entry by Baolin Wang. Suggested-by: Matthew Wilcox Signed-off-by: Daniel Gomez Signed-off-by: Baolin Wang --- mm/shmem.c | 25 ++++++++++++++++--------- 1 file changed, 16 insertions(+), 9 deletions(-) diff --git a/mm/shmem.c b/mm/shmem.c index 02fb188d627f..d0d54939da48 100644 --- a/mm/shmem.c +++ b/mm/shmem.c @@ -856,18 +856,22 @@ static void shmem_delete_from_page_cache(struct folio= *folio, void *radswap) } =20 /* - * Remove swap entry from page cache, free the swap and its page cache. + * Remove swap entry from page cache, free the swap and its page cache. Re= turns + * the number of pages being freed. 0 means entry not found in XArray (0 p= ages + * being freed). */ -static int shmem_free_swap(struct address_space *mapping, - pgoff_t index, void *radswap) +static long shmem_free_swap(struct address_space *mapping, + pgoff_t index, void *radswap) { + int order =3D xa_get_order(&mapping->i_pages, index); void *old; =20 old =3D xa_cmpxchg_irq(&mapping->i_pages, index, radswap, NULL, 0); if (old !=3D radswap) - return -ENOENT; - free_swap_and_cache(radix_to_swp_entry(radswap)); - return 0; + return 0; + free_swap_and_cache_nr(radix_to_swp_entry(radswap), 1 << order); + + return 1 << order; } =20 /* @@ -1019,7 +1023,7 @@ static void shmem_undo_range(struct inode *inode, lof= f_t lstart, loff_t lend, if (xa_is_value(folio)) { if (unfalloc) continue; - nr_swaps_freed +=3D !shmem_free_swap(mapping, + nr_swaps_freed +=3D shmem_free_swap(mapping, indices[i], folio); continue; } @@ -1086,14 +1090,17 @@ static void shmem_undo_range(struct inode *inode, l= off_t lstart, loff_t lend, folio =3D fbatch.folios[i]; =20 if (xa_is_value(folio)) { + long swaps_freed; + if (unfalloc) continue; - if (shmem_free_swap(mapping, indices[i], folio)) { + swaps_freed =3D shmem_free_swap(mapping, indices[i], folio); + if (!swaps_freed) { /* Swap was replaced by page: retry */ index =3D indices[i]; break; } - nr_swaps_freed++; + nr_swaps_freed +=3D swaps_freed; continue; } =20 --=20 2.39.3