From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from szxga01-in.huawei.com (szxga01-in.huawei.com [45.249.212.187]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 1969CEACE; Tue, 16 Dec 2025 02:12:21 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=45.249.212.187 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1765851145; cv=none; b=YHqunuB5/mgS9eLlegiUnLDmE7Qn+z4P3tyDlZxJOg8o2kTBYk1ILI5yRSyaREAURTl2EzsiLe1seMPMTz++LkDkNmnXcVJw2W5GcJdB+aLCdr7jgE2gC+UIuKfm/DpqqfrFHaRoIfTrU2kG792djQxsisEe11kdHh0RlpDOUM8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1765851145; c=relaxed/simple; bh=Rm61Z34pGhWCnpHDgIv6eJG+Vfb/x1DU4A+H4PmKqMM=; h=From:To:CC:Subject:Date:Message-ID:Content-Type:MIME-Version; b=odzhW/p23Latim5xpmh3DsHjNAT83TYO4lDc03/fvPLcLV2TmolK77RxOkIw0CLd8SPMC7H2KZ3LhidtTRrUEx6b4TC2tSxP43p5epOIQzvJEkIIm8/5Rb2FlkAf8vIvetXDlk7X9bFvcQRG+0GDPqOKJhbXdRJ9h/7UAgz+IOs= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=huawei.com; spf=pass smtp.mailfrom=huawei.com; dkim=pass (1024-bit key) header.d=huawei.com header.i=@huawei.com header.b=CI7GZIQU; dkim=pass (1024-bit key) header.d=huawei.com header.i=@huawei.com header.b=CI7GZIQU; arc=none smtp.client-ip=45.249.212.187 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=huawei.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=huawei.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=huawei.com header.i=@huawei.com header.b="CI7GZIQU"; dkim=pass (1024-bit key) header.d=huawei.com header.i=@huawei.com header.b="CI7GZIQU" dkim-signature: v=1; a=rsa-sha256; d=huawei.com; s=dkim; c=relaxed/relaxed; q=dns/txt; h=From; bh=Ny61MqGFroEBN84CEhZ8ZqH1kOgw2JrvF+IHTRz9+B4=; b=CI7GZIQUTPuQLuGEgWYWj9pr8ko3O/HhHvYlo1byFV5Wl71mDONiwT1QyebJbxJItF5CAK737 JOZhbgnxPXO/Y6FMtzOhFI9XYwILLcTHWfTmIdTvPfeo1TfzwfXyWutdTWyZKZRVQeks/wYVdUM 1bN7V54OGKyvsgK3XCmrbQk= Received: from canpmsgout08.his.huawei.com (unknown [172.19.92.156]) by szxga01-in.huawei.com (SkyGuard) with ESMTPS id 4dVgRM34jkz1BFPS; Tue, 16 Dec 2025 10:11:59 +0800 (CST) dkim-signature: v=1; a=rsa-sha256; d=huawei.com; s=dkim; c=relaxed/relaxed; q=dns/txt; h=From; bh=Ny61MqGFroEBN84CEhZ8ZqH1kOgw2JrvF+IHTRz9+B4=; b=CI7GZIQUTPuQLuGEgWYWj9pr8ko3O/HhHvYlo1byFV5Wl71mDONiwT1QyebJbxJItF5CAK737 JOZhbgnxPXO/Y6FMtzOhFI9XYwILLcTHWfTmIdTvPfeo1TfzwfXyWutdTWyZKZRVQeks/wYVdUM 1bN7V54OGKyvsgK3XCmrbQk= Received: from mail.maildlp.com (unknown [172.19.88.163]) by canpmsgout08.his.huawei.com (SkyGuard) with ESMTPS id 4dVgPH0yCwzmVVR; Tue, 16 Dec 2025 10:10:11 +0800 (CST) Received: from dggpemf500009.china.huawei.com (unknown [7.185.36.50]) by mail.maildlp.com (Postfix) with ESMTPS id 26A8E1800B2; Tue, 16 Dec 2025 10:12:11 +0800 (CST) Received: from dggpemf500012.china.huawei.com (7.185.36.8) by dggpemf500009.china.huawei.com (7.185.36.50) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1544.11; Tue, 16 Dec 2025 10:12:10 +0800 Received: from dggpemf500012.china.huawei.com ([7.185.36.8]) by dggpemf500012.china.huawei.com ([7.185.36.8]) with mapi id 15.02.1544.011; Tue, 16 Dec 2025 10:12:10 +0800 From: zhangqilong To: Matthew Wilcox CC: "akpm@linux-foundation.org" , "david@kernel.org" , "lorenzo.stoakes@oracle.com" , "corbet@lwn.net" , "ziy@nvidia.com" , "baolin.wang@linux.alibaba.com" , "Liam.Howlett@oracle.com" , "npache@redhat.com" , "ryan.roberts@arm.com" , "dev.jain@arm.com" , "baohua@kernel.org" , "lance.yang@linux.dev" , "vbabka@suse.cz" , "rppt@kernel.org" , "surenb@google.com" , "mhocko@suse.com" , "Wangkefeng (OS Kernel Lab)" , Sunnanyong , "linux-mm@kvack.org" , "linux-doc@vger.kernel.org" , "linux-kernel@vger.kernel.org" Subject: Re: [PATCH next 0/2] THP COW support for private executable file mmap Thread-Topic: [PATCH next 0/2] THP COW support for private executable file mmap Thread-Index: AdxuLvzPiGNlB0SW/Ee39Xxvv0vdtg== Date: Tue, 16 Dec 2025 02:12:10 +0000 Message-ID: Accept-Language: zh-CN, en-US Content-Language: zh-CN X-MS-Has-Attach: X-MS-TNEF-Correlator: Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 > On Mon, Dec 15, 2025 at 08:34:05PM +0800, Zhang Qilong wrote: > > This patch series implementate THP COW for private executable file > > mmap. It's major designed to increase the iTLB cache hit rate for hot > > patching application, and we add a new sysfs knob to disable or enable > > it. >=20 > You're going to have to provide data to get this patch in. We've deliber= ately > not done this in the past due to memory consumption overhead. Year, memory consumption overhead is a serious issue, we will conduct a car= eful evaluation > So you need to prove that's now the wrong decision to make. >=20 > Microbenchmarks would be a bare minimum, but what are really needed are > numbers from actual workloads. Okay, I'm also trying to gather some test data locally(include microbenchma= rks and actual workloads). I'll attach the results once I have finished. Thank you for your suggestion= . -- Thanks, Zhang