Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755385AbdGXFUk (ORCPT ); Mon, 24 Jul 2017 01:20:40 -0400 Received: from mga04.intel.com ([192.55.52.120]:7383 "EHLO mga04.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752922AbdGXFTK (ORCPT ); Mon, 24 Jul 2017 01:19:10 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.40,405,1496127600"; d="scan'208";a="290458778" From: "Huang, Ying" To: Andrew Morton Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Huang Ying , Johannes Weiner , Minchan Kim , Hugh Dickins , Shaohua Li , Rik van Riel , Andrea Arcangeli , "Kirill A . Shutemov" , Michal Hocko Subject: [PATCH -mm -v3 12/12] mm, THP, swap: Add THP swapping out fallback counting Date: Mon, 24 Jul 2017 13:18:40 +0800 Message-Id: <20170724051840.2309-13-ying.huang@intel.com> X-Mailer: git-send-email 2.13.2 In-Reply-To: <20170724051840.2309-1-ying.huang@intel.com> References: <20170724051840.2309-1-ying.huang@intel.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2155 Lines: 64 From: Huang Ying When swapping out THP (Transparent Huge Page), instead of swapping out the THP as a whole, sometimes we have to fallback to split the THP into normal pages before swapping, because no free swap clusters are available, or cgroup limit is exceeded, etc. To count the number of the fallback, a new VM event THP_SWPOUT_FALLBACK is added, and counted when we fallback to split the THP. Signed-off-by: "Huang, Ying" Cc: Johannes Weiner Cc: Minchan Kim Cc: Hugh Dickins Cc: Shaohua Li Cc: Rik van Riel Cc: Andrea Arcangeli Cc: "Kirill A . Shutemov" Cc: Michal Hocko --- include/linux/vm_event_item.h | 1 + mm/vmscan.c | 3 +++ mm/vmstat.c | 1 + 3 files changed, 5 insertions(+) diff --git a/include/linux/vm_event_item.h b/include/linux/vm_event_item.h index c75024e80eed..e02820fc2861 100644 --- a/include/linux/vm_event_item.h +++ b/include/linux/vm_event_item.h @@ -86,6 +86,7 @@ enum vm_event_item { PGPGIN, PGPGOUT, PSWPIN, PSWPOUT, THP_ZERO_PAGE_ALLOC, THP_ZERO_PAGE_ALLOC_FAILED, THP_SWPOUT, + THP_SWPOUT_FALLBACK, #endif #ifdef CONFIG_MEMORY_BALLOON BALLOON_INFLATE, diff --git a/mm/vmscan.c b/mm/vmscan.c index 7472ddafc14a..4f7212f8ca00 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -1153,6 +1153,9 @@ static unsigned long shrink_page_list(struct list_head *page_list, if (split_huge_page_to_list(page, page_list)) goto activate_locked; +#ifdef CONFIG_TRANSPARENT_HUGEPAGE + count_vm_event(THP_SWPOUT_FALLBACK); +#endif if (!add_to_swap(page)) goto activate_locked; } diff --git a/mm/vmstat.c b/mm/vmstat.c index bccf426453cd..e131b51654c7 100644 --- a/mm/vmstat.c +++ b/mm/vmstat.c @@ -1072,6 +1072,7 @@ const char * const vmstat_text[] = { "thp_zero_page_alloc", "thp_zero_page_alloc_failed", "thp_swpout", + "thp_swpout_fallback", #endif #ifdef CONFIG_MEMORY_BALLOON "balloon_inflate", -- 2.13.2