From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pf1-f197.google.com (mail-pf1-f197.google.com [209.85.210.197]) by kanga.kvack.org (Postfix) with ESMTP id B1DD66B3F6A for ; Mon, 27 Aug 2018 03:55:49 -0400 (EDT) Received: by mail-pf1-f197.google.com with SMTP id d22-v6so11293122pfn.3 for ; Mon, 27 Aug 2018 00:55:49 -0700 (PDT) Received: from mga05.intel.com (mga05.intel.com. [192.55.52.43]) by mx.google.com with ESMTPS id j5-v6si13565094plk.406.2018.08.27.00.55.48 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 27 Aug 2018 00:55:48 -0700 (PDT) From: Huang Ying Subject: [PATCH 3/3] swap: Clear si->swap_map[] in swap_free_cluster() Date: Mon, 27 Aug 2018 15:55:35 +0800 Message-Id: <20180827075535.17406-4-ying.huang@intel.com> In-Reply-To: <20180827075535.17406-1-ying.huang@intel.com> References: <20180827075535.17406-1-ying.huang@intel.com> Sender: owner-linux-mm@kvack.org List-ID: To: Andrew Morton Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Huang Ying , Dave Hansen , Michal Hocko , Johannes Weiner , Shaohua Li , Hugh Dickins , Minchan Kim si->swap_map[] of the swap entries in cluster needs to be cleared during freeing. Previously, this is done in the caller of swap_free_cluster(). This may cause code duplication (one user now, will add more users later) and lock/unlock cluster unnecessarily. In this patch, the clearing code is moved to swap_free_cluster() to avoid the downside. Signed-off-by: "Huang, Ying" Cc: Dave Hansen Cc: Michal Hocko Cc: Johannes Weiner Cc: Shaohua Li Cc: Hugh Dickins Cc: Minchan Kim --- mm/swapfile.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) diff --git a/mm/swapfile.c b/mm/swapfile.c index ef974bbd7715..97a1bd1a7c9a 100644 --- a/mm/swapfile.c +++ b/mm/swapfile.c @@ -933,6 +933,7 @@ static void swap_free_cluster(struct swap_info_struct *si, unsigned long idx) struct swap_cluster_info *ci; ci = lock_cluster(si, offset); + memset(si->swap_map + offset, 0, SWAPFILE_CLUSTER); cluster_set_count_flag(ci, 0, 0); free_cluster(si, idx); unlock_cluster(ci); @@ -1309,9 +1310,6 @@ void put_swap_page(struct page *page, swp_entry_t entry) if (free_entries == SWAPFILE_CLUSTER) { unlock_cluster_or_swap_info(si, ci); spin_lock(&si->lock); - ci = lock_cluster(si, offset); - memset(map, 0, SWAPFILE_CLUSTER); - unlock_cluster(ci); mem_cgroup_uncharge_swap(entry, SWAPFILE_CLUSTER); swap_free_cluster(si, idx); spin_unlock(&si->lock); -- 2.16.4