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[2620:137:e000::1:20]) by mx.google.com with ESMTP id l71-20020a63884a000000b003c62121f239si24169279pgd.808.2022.06.07.14.03.17; Tue, 07 Jun 2022 14:03:40 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20; Authentication-Results: mx.google.com; dkim=pass header.i=@linux-foundation.org header.s=korg header.b=yNSqos55; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1378689AbiFGVBo (ORCPT + 99 others); Tue, 7 Jun 2022 17:01:44 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34952 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1357020AbiFGT6h (ORCPT ); Tue, 7 Jun 2022 15:58:37 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 00AEA4B84C for ; Tue, 7 Jun 2022 11:24:20 -0700 (PDT) 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 436CDB82380 for ; 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-Spam-Status: No, score=-8.3 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,NICE_REPLY_A,RCVD_IN_DNSWL_HI, SPF_HELO_NONE,SPF_PASS,T_SCC_BODY_TEXT_LINE autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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.