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=-5.3 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,NICE_REPLY_A, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=no 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 9EEBFC433B4 for ; Wed, 21 Apr 2021 16:56:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6472461449 for ; Wed, 21 Apr 2021 16:56:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236778AbhDUQ5G (ORCPT ); Wed, 21 Apr 2021 12:57:06 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34074 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S244469AbhDUQ5A (ORCPT ); Wed, 21 Apr 2021 12:57:00 -0400 Received: from mail-il1-x134.google.com (mail-il1-x134.google.com [IPv6:2607:f8b0:4864:20::134]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A8FDFC06138A for ; Wed, 21 Apr 2021 09:56:20 -0700 (PDT) Received: by mail-il1-x134.google.com with SMTP id r5so27299940ilb.2 for ; Wed, 21 Apr 2021 09:56:20 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel-dk.20150623.gappssmtp.com; s=20150623; h=subject:to:cc:references:from:message-id:date:user-agent :mime-version:in-reply-to:content-language:content-transfer-encoding; bh=PZFSOtZMmhPTU9JBlcmY+DOQRzSewGE0IcmlQTJi7S0=; b=bNTNqa0HnJa/B96/tgwhvBuQpuVTe1iPwITyvrdSrRHPB5DoRxLBUdBPLtLHjvIomh Ldqygq6t4Kkok2mJznizH5aq0ldY4422+lg1pAEcKFumDSlgL/0cAfmic/MOR4xeFRtM w6wmmTrJwmyZyeM2q0eiZUxxzm3f3r+0r41D2QZs0ngWt8J9xnYiCjZREmVVFuGlADNZ SzCHkhwXHuminZIE748/nkNkad8VDEspwN0xIcJ8fFbsmTNvUmED3o20aU7KzmrJo5vM Kl3Y2pOEN/X0qSYNgPu37WaqSA/DUC/s8XpqF99sag11yzyHd7t4Y+YUKyD35tN75Sue hkTA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=PZFSOtZMmhPTU9JBlcmY+DOQRzSewGE0IcmlQTJi7S0=; b=ADsTkajT3+tatzWwG+k+Kjjn45KwOcLHIr78BEKH77O+y+xM/pQ52MjA4+G5It5WEF /W1MO8rK7O91mYAIEw178ubYoRwH6Cf3pIf+8Lo0Am3kSROPPk0J1FTp6EwRy3ku1B5l to4i1J4wRN+c2LTJ76TRS8Q2kH1E8d4tjIi6BLFOSufFyyy/zQ+xc3g2V7vAd9+rV9o6 ZTk623Awfx7U46luQB3ebh6YSdZ3oRQMWYAX9wxyztSSZsAIXhVLbI+A6qWayrVuA6FV oqJUxZAznu3Rg/x0vdDpfIiRUuV8RvpyR42Oi9QZ9Z2nwIgh8XG7w+qYPIiCpCodv2L/ VZew== X-Gm-Message-State: AOAM532Skze6PpdYlmdhVPRVbq4Gm+DVKH4OoE4VY51bEW8k52WySS+X H95A0EWs88K5bVaOigCVQTqn+g== X-Google-Smtp-Source: ABdhPJz59S8ZopGsXeRykQwRa/BtMRNsMKDwQ8qauGoKqx1v9yg1pXNk1bR0YA5rQYC2szzx/kW01Q== X-Received: by 2002:a92:2c02:: with SMTP id t2mr26500868ile.233.1619024178693; Wed, 21 Apr 2021 09:56:18 -0700 (PDT) Received: from [192.168.1.30] ([65.144.74.34]) by smtp.gmail.com with ESMTPSA id a17sm1248701ili.6.2021.04.21.09.56.17 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 21 Apr 2021 09:56:18 -0700 (PDT) Subject: Re: [PATCH] brd: expose number of allocated pages in debugfs To: Saravanan D , linux-block@vger.kernel.org, linux-kernel@vger.kernel.org Cc: jkkm@fb.com, tj@kernel.org, kernel-team@fb.com, Calvin Owens References: <20210416211829.4002947-1-saravanand@fb.com> From: Jens Axboe Message-ID: Date: Wed, 21 Apr 2021 10:56:12 -0600 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.10.0 MIME-Version: 1.0 In-Reply-To: <20210416211829.4002947-1-saravanand@fb.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 4/16/21 3:18 PM, Saravanan D wrote: > From: Calvin Owens > > While the maximum size of each ramdisk is defined either > as a module parameter, or compile time default, it's impossible > to know how many pages have currently been allocated by each > ram%d device, since they're allocated when used and never freed. > > This patch creates a new directory at this location: > > ยป /sys/kernel/debug/ramdisk_pages/ > > ...which will contain a file named "ram%d" for each instantiated > ramdisk on the system. The file is read-only, and read() will > output the number of pages currently held by that ramdisk. I folded in the justification and applied it for 5.13, thanks. -- Jens Axboe