From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pf0-f197.google.com (mail-pf0-f197.google.com [209.85.192.197]) by kanga.kvack.org (Postfix) with ESMTP id 35A826B026A for ; Thu, 12 Jul 2018 19:37:07 -0400 (EDT) Received: by mail-pf0-f197.google.com with SMTP id i123-v6so11421644pfc.13 for ; Thu, 12 Jul 2018 16:37:07 -0700 (PDT) Received: from mga17.intel.com (mga17.intel.com. [192.55.52.151]) by mx.google.com with ESMTPS id v14-v6si19305318pga.270.2018.07.12.16.37.05 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 12 Jul 2018 16:37:06 -0700 (PDT) From: "Huang, Ying" Subject: [PATCH 6/6] swap, put_swap_page: Share more between huge/normal code path Date: Fri, 13 Jul 2018 07:36:36 +0800 Message-Id: <20180712233636.20629-7-ying.huang@intel.com> In-Reply-To: <20180712233636.20629-1-ying.huang@intel.com> References: <20180712233636.20629-1-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 , Rik van Riel , Daniel Jordan , Dan Williams From: Huang Ying In this patch, locking related code is shared between huge/normal code path in put_swap_page() to reduce code duplication. And `free_entries == 0` case is merged into more general `free_entries != SWAPFILE_CLUSTER` case, because the new locking method makes it easy. The added lines is same as the removed lines. But the code size is increased when CONFIG_TRANSPARENT_HUGEPAGE=n. text data bss dec hex filename base: 24215 2028 340 26583 67d7 mm/swapfile.o unified: 24577 2028 340 26945 6941 mm/swapfile.o Signed-off-by: "Huang, Ying" Cc: Dave Hansen Cc: Michal Hocko Cc: Johannes Weiner Cc: Shaohua Li Cc: Hugh Dickins Cc: Minchan Kim Cc: Rik van Riel Cc: Daniel Jordan Cc: Dan Williams --- mm/swapfile.c | 20 ++++++++++---------- 1 file changed, 10 insertions(+), 10 deletions(-) diff --git a/mm/swapfile.c b/mm/swapfile.c index bc488bf36c86..17dce780b4c8 100644 --- a/mm/swapfile.c +++ b/mm/swapfile.c @@ -1280,8 +1280,8 @@ void put_swap_page(struct page *page, swp_entry_t entry) if (!si) return; + ci = lock_cluster_or_swap_info(si, offset); if (nr == SWAPFILE_CLUSTER) { - ci = lock_cluster(si, offset); VM_BUG_ON(!cluster_is_huge(ci)); map = si->swap_map + offset; for (i = 0; i < SWAPFILE_CLUSTER; i++) { @@ -1290,13 +1290,9 @@ void put_swap_page(struct page *page, swp_entry_t entry) if (val == SWAP_HAS_CACHE) free_entries++; } - if (!free_entries) { - for (i = 0; i < SWAPFILE_CLUSTER; i++) - map[i] &= ~SWAP_HAS_CACHE; - } cluster_clear_huge(ci); - unlock_cluster(ci); 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); @@ -1307,12 +1303,16 @@ void put_swap_page(struct page *page, swp_entry_t entry) return; } } - if (nr == 1 || free_entries) { - for (i = 0; i < nr; i++, entry.val++) { - if (!__swap_entry_free(si, entry, SWAP_HAS_CACHE)) - free_swap_slot(entry); + for (i = 0; i < nr; i++, entry.val++) { + if (!__swap_entry_free_locked(si, offset + i, SWAP_HAS_CACHE)) { + unlock_cluster_or_swap_info(si, ci); + free_swap_slot(entry); + if (i == nr - 1) + return; + lock_cluster_or_swap_info(si, offset); } } + unlock_cluster_or_swap_info(si, ci); } #ifdef CONFIG_THP_SWAP -- 2.16.4