From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.4 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,USER_AGENT_MUTT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 14D4CC04AAB for ; Tue, 7 May 2019 12:54:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id DDB07205ED for ; Tue, 7 May 2019 12:54:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726685AbfEGMyf (ORCPT ); Tue, 7 May 2019 08:54:35 -0400 Received: from mx1.redhat.com ([209.132.183.28]:59966 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726000AbfEGMye (ORCPT ); Tue, 7 May 2019 08:54:34 -0400 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 3544B81E07; Tue, 7 May 2019 12:54:34 +0000 (UTC) Received: from x230.aquini.net (dhcp-17-61.bos.redhat.com [10.18.17.61]) by smtp.corp.redhat.com (Postfix) with ESMTPS id CDE1E5C3FA; Tue, 7 May 2019 12:54:32 +0000 (UTC) Date: Tue, 7 May 2019 08:54:31 -0400 From: Rafael Aquini To: Joel Savitz Cc: linux-kernel@vger.kernel.org, Alexey Dobriyan , Andrew Morton , Vlastimil Babka , "Aneesh Kumar K.V" , Michael Ellerman , Ram Pai , Andrea Arcangeli , Huang Ying , Sandeep Patil , Yury Norov , linux-fsdevel@vger.kernel.org Subject: Re: [PATCH v3] fs/proc: add VmTaskSize field to /proc/$$/status Message-ID: <20190507125430.GA31025@x230.aquini.net> References: <1557158023-23021-1-git-send-email-jsavitz@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1557158023-23021-1-git-send-email-jsavitz@redhat.com> User-Agent: Mutt/1.11.3 (2019-02-01) X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.25]); Tue, 07 May 2019 12:54:34 +0000 (UTC) Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org On Mon, May 06, 2019 at 11:53:43AM -0400, Joel Savitz wrote: > There is currently no easy and architecture-independent way to find the > lowest unusable virtual address available to a process without > brute-force calculation. This patch allows a user to easily retrieve > this value via /proc//status. > > Using this patch, any program that previously needed to waste cpu cycles > recalculating a non-sensitive process-dependent value already known to > the kernel can now be optimized to use this mechanism. > > Signed-off-by: Joel Savitz > --- > Documentation/filesystems/proc.txt | 2 ++ > fs/proc/task_mmu.c | 2 ++ > 2 files changed, 4 insertions(+) > > diff --git a/Documentation/filesystems/proc.txt b/Documentation/filesystems/proc.txt > index 66cad5c86171..1c6a912e3975 100644 > --- a/Documentation/filesystems/proc.txt > +++ b/Documentation/filesystems/proc.txt > @@ -187,6 +187,7 @@ read the file /proc/PID/status: > VmLib: 1412 kB > VmPTE: 20 kb > VmSwap: 0 kB > + VmTaskSize: 137438953468 kB > HugetlbPages: 0 kB > CoreDumping: 0 > THP_enabled: 1 > @@ -263,6 +264,7 @@ Table 1-2: Contents of the status files (as of 4.19) > VmPTE size of page table entries > VmSwap amount of swap used by anonymous private data > (shmem swap usage is not included) > + VmTaskSize lowest unusable address in process virtual memory Can we change this help text to "size of process' virtual address space memory" ? > HugetlbPages size of hugetlb memory portions > CoreDumping process's memory is currently being dumped > (killing the process may lead to a corrupted core) > diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c > index 95ca1fe7283c..0af7081f7b19 100644 > --- a/fs/proc/task_mmu.c > +++ b/fs/proc/task_mmu.c > @@ -74,6 +74,8 @@ void task_mem(struct seq_file *m, struct mm_struct *mm) > seq_put_decimal_ull_width(m, > " kB\nVmPTE:\t", mm_pgtables_bytes(mm) >> 10, 8); > SEQ_PUT_DEC(" kB\nVmSwap:\t", swap); > + seq_put_decimal_ull_width(m, > + " kB\nVmTaskSize:\t", mm->task_size >> 10, 8); > seq_puts(m, " kB\n"); > hugetlb_report_usage(m, mm); > } > -- > 2.18.1 > Acked-by: Rafael Aquini