From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751553AbdBXVcy (ORCPT ); Fri, 24 Feb 2017 16:32:54 -0500 Received: from mx0a-00082601.pphosted.com ([67.231.145.42]:33239 "EHLO mx0a-00082601.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751304AbdBXVbx (ORCPT ); Fri, 24 Feb 2017 16:31:53 -0500 Smtp-Origin-Hostprefix: devbig From: Shaohua Li Smtp-Origin-Hostname: devbig638.prn2.facebook.com To: , CC: , , , , , , , Smtp-Origin-Cluster: prn2c22 Subject: [PATCH V5 6/6] proc: show MADV_FREE pages info in smaps Date: Fri, 24 Feb 2017 13:31:49 -0800 Message-ID: <89efde633559de1ec07444f2ef0f4963a97a2ce8.1487965799.git.shli@fb.com> X-Mailer: git-send-email 2.9.3 In-Reply-To: References: X-FB-Internal: Safe MIME-Version: 1.0 Content-Type: text/plain X-Proofpoint-Spam-Reason: safe X-FB-Internal: Safe X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:,, definitions=2017-02-24_13:,, signatures=0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org show MADV_FREE pages info of each vma in smaps. The interface is for diganose or monitoring purpose, userspace could use it to understand what happens in the application. Since userspace could dirty MADV_FREE pages without notice from kernel, this interface is the only place we can get accurate accounting info about MADV_FREE pages. Cc: Michal Hocko Cc: Hugh Dickins Cc: Rik van Riel Cc: Mel Gorman Cc: Andrew Morton Acked-by: Johannes Weiner Acked-by: Minchan Kim Signed-off-by: Shaohua Li --- Documentation/filesystems/proc.txt | 4 ++++ fs/proc/task_mmu.c | 8 +++++++- 2 files changed, 11 insertions(+), 1 deletion(-) diff --git a/Documentation/filesystems/proc.txt b/Documentation/filesystems/proc.txt index c94b467..45853e1 100644 --- a/Documentation/filesystems/proc.txt +++ b/Documentation/filesystems/proc.txt @@ -412,6 +412,7 @@ Private_Clean: 0 kB Private_Dirty: 0 kB Referenced: 892 kB Anonymous: 0 kB +LazyFree: 0 kB AnonHugePages: 0 kB ShmemPmdMapped: 0 kB Shared_Hugetlb: 0 kB @@ -441,6 +442,9 @@ accessed. "Anonymous" shows the amount of memory that does not belong to any file. Even a mapping associated with a file may contain anonymous pages: when MAP_PRIVATE and a page is modified, the file page is replaced by a private anonymous copy. +"LazyFree" shows the amount of memory which is marked by madvise(MADV_FREE). +The memory isn't freed immediately with madvise(). It's freed in memory +pressure if the memory is clean. "AnonHugePages" shows the ammount of memory backed by transparent hugepage. "ShmemPmdMapped" shows the ammount of shared (shmem/tmpfs) memory backed by huge pages. diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c index ee3efb2..8a5ec00 100644 --- a/fs/proc/task_mmu.c +++ b/fs/proc/task_mmu.c @@ -440,6 +440,7 @@ struct mem_size_stats { unsigned long private_dirty; unsigned long referenced; unsigned long anonymous; + unsigned long lazyfree; unsigned long anonymous_thp; unsigned long shmem_thp; unsigned long swap; @@ -456,8 +457,11 @@ static void smaps_account(struct mem_size_stats *mss, struct page *page, int i, nr = compound ? 1 << compound_order(page) : 1; unsigned long size = nr * PAGE_SIZE; - if (PageAnon(page)) + if (PageAnon(page)) { mss->anonymous += size; + if (!PageSwapBacked(page) && !dirty && !PageDirty(page)) + mss->lazyfree += size; + } mss->resident += size; /* Accumulate the size in pages that have been accessed. */ @@ -770,6 +774,7 @@ static int show_smap(struct seq_file *m, void *v, int is_pid) "Private_Dirty: %8lu kB\n" "Referenced: %8lu kB\n" "Anonymous: %8lu kB\n" + "LazyFree: %8lu kB\n" "AnonHugePages: %8lu kB\n" "ShmemPmdMapped: %8lu kB\n" "Shared_Hugetlb: %8lu kB\n" @@ -788,6 +793,7 @@ static int show_smap(struct seq_file *m, void *v, int is_pid) mss.private_dirty >> 10, mss.referenced >> 10, mss.anonymous >> 10, + mss.lazyfree >> 10, mss.anonymous_thp >> 10, mss.shmem_thp >> 10, mss.shared_hugetlb >> 10, -- 2.9.3