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 Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4B7DDCCA47C for ; Tue, 7 Jun 2022 18:24:23 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 8F5B56B0074; Tue, 7 Jun 2022 14:24:22 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 8A4956B0075; Tue, 7 Jun 2022 14:24:22 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 76C396B0078; Tue, 7 Jun 2022 14:24:22 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0014.hostedemail.com [216.40.44.14]) by kanga.kvack.org (Postfix) with ESMTP id 6778E6B0074 for ; Tue, 7 Jun 2022 14:24:22 -0400 (EDT) Received: from smtpin23.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay10.hostedemail.com (Postfix) with ESMTP id DE047134A for ; Tue, 7 Jun 2022 18:24:21 +0000 (UTC) X-FDA: 79552264722.23.C732E1F Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by imf12.hostedemail.com (Postfix) with ESMTP id 421564003E for ; Tue, 7 Jun 2022 18:23:34 +0000 (UTC) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 584A5B82381; Tue, 7 Jun 2022 18:24:19 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id BE8D3C385A2; Tue, 7 Jun 2022 18:24:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1654626258; bh=WQze2jI4iLnLMMFgWUExS0e2SHPtgx75puArLYQyzlY=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=yNSqos55DIOrQcDPFBGRPyBCr/BoKJ6v2elSgDa9VbxpUZXDxHDJcfc7OVVYp7dyF bnVDWVaOXXUxUBpoikT79XhshrnvuF5VRvM6hOZLCK89Nt7J+njfb2Q0U/q2/8ulwl zjBNPDzDoryS04iD9Nd7dG+GfVOJJCzmCkHtAAg8= Date: Tue, 7 Jun 2022 11:24:17 -0700 From: Andrew Morton To: Charan Teja Kalla Cc: , , , , , , , Subject: Re: [PATCH RESEND V5,2/2] mm: shmem: implement POSIX_FADV_[WILL|DONT]NEED for shmem Message-Id: <20220607112417.5b47a5f55f20fe1f6cfb14e6@linux-foundation.org> In-Reply-To: <7584364f-3aaf-282a-0a67-d8329a3415dc@quicinc.com> References: <20220531142135.666b1fcf506e4a327af98ff9@linux-foundation.org> <7584364f-3aaf-282a-0a67-d8329a3415dc@quicinc.com> X-Mailer: Sylpheed 3.7.0 (GTK+ 2.24.33; x86_64-redhat-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Rspamd-Server: rspam01 X-Rspamd-Queue-Id: 421564003E Authentication-Results: imf12.hostedemail.com; dkim=pass header.d=linux-foundation.org header.s=korg header.b=yNSqos55; dmarc=none; spf=pass (imf12.hostedemail.com: domain of akpm@linux-foundation.org designates 145.40.68.75 as permitted sender) smtp.mailfrom=akpm@linux-foundation.org X-Stat-Signature: quxnifawp7twwedttznbcu7fdsyshnqf X-Rspam-User: X-HE-Tag: 1654626214-278666 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000035, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Tue, 7 Jun 2022 20:22:34 +0530 Charan Teja Kalla wrote: > > Is there an actual userspace/driver combination which will use this? > > Has the new feature been tested in such an arrangement? And if so, > > which driver(s)? > > > > Currently my organization is using this setup where it does makes use of > the shmem infrastructure to allocate the pages and its fd is passed to > the user. The user is now deciding on when to reclaim these pages to > free up the memory through already presented vfs_fadvise(DONTNEED) > system call and bringing back them through vfs_fadvise(WILLNEED), when OK, thanks. Please capture all these thoughts in the [0/n] changelog, leave it a few days for reviewer input then resend and I'll take a closer look. The patches don't seem to be getting a lot of traction.