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 43390C43334 for ; Tue, 26 Jul 2022 13:28:32 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id C9193900002; Tue, 26 Jul 2022 09:28:31 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id C40EC8E0001; Tue, 26 Jul 2022 09:28:31 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id B3009900002; Tue, 26 Jul 2022 09:28:31 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0015.hostedemail.com [216.40.44.15]) by kanga.kvack.org (Postfix) with ESMTP id A1E748E0001 for ; Tue, 26 Jul 2022 09:28:31 -0400 (EDT) Received: from smtpin09.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay08.hostedemail.com (Postfix) with ESMTP id 7931B1403F4 for ; Tue, 26 Jul 2022 13:28:31 +0000 (UTC) X-FDA: 79729330422.09.8B23E34 Received: from szxga03-in.huawei.com (szxga03-in.huawei.com [45.249.212.189]) by imf22.hostedemail.com (Postfix) with ESMTP id B2C11C0007 for ; Tue, 26 Jul 2022 13:28:30 +0000 (UTC) Received: from dggemv711-chm.china.huawei.com (unknown [172.30.72.57]) by szxga03-in.huawei.com (SkyGuard) with ESMTP id 4Lsd4K140wz9swR; Tue, 26 Jul 2022 21:27:13 +0800 (CST) Received: from kwepemm600010.china.huawei.com (7.193.23.86) by dggemv711-chm.china.huawei.com (10.1.198.66) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.24; Tue, 26 Jul 2022 21:28:22 +0800 Received: from huawei.com (10.174.179.164) by kwepemm600010.china.huawei.com (7.193.23.86) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.24; Tue, 26 Jul 2022 21:28:21 +0800 From: Liu Zixian To: CC: , , , , Subject: Re: Re: [PATCH] shmem: support huge_fault to avoid pmd split Date: Tue, 26 Jul 2022 21:28:20 +0800 Message-ID: <20220726132820.1690-1-liuzixian4@huawei.com> X-Mailer: git-send-email 2.29.2.windows.3 In-Reply-To: References: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain X-Originating-IP: [10.174.179.164] X-ClientProxiedBy: dggems705-chm.china.huawei.com (10.3.19.182) To kwepemm600010.china.huawei.com (7.193.23.86) X-CFilter-Loop: Reflected ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1658842111; a=rsa-sha256; cv=none; b=OWOw69ikn9YjwUi2TaVj8uI8o+Hx5O8iMkr7WVZBQ3p+9n0UG0h8F3Ow5f/3XEV9bVT8Nz T5+0MH3lkcAVNmqUHCozoxGqVuTce24RzcpDn6cNDzO1L9oviWnKWqnS2/yMPKa1pdyJ4c 5F28qVUdX+jhA4X1BkT7m30umEzwYjM= ARC-Authentication-Results: i=1; imf22.hostedemail.com; dkim=none; spf=pass (imf22.hostedemail.com: domain of liuzixian4@huawei.com designates 45.249.212.189 as permitted sender) smtp.mailfrom=liuzixian4@huawei.com; dmarc=pass (policy=quarantine) header.from=huawei.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1658842111; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=OP/f795R5zRNoD4mLKrE/G0XQ57gmX2FvSJNpBhLE9A=; b=ehEqEHXo9UiN7WdZ5za//5uhsUOQhU2ssuyhOLOy55kXL4uYd/j+8+uBHHXod2tTbdOknK iDUuI4y+yCe4U0qHpS+hQxCr1fCwMi/cZk2tQJAyJj9GfsvVVScHuseLnVVn9rkek6C/+s pTTN4rWyLALZANYtrzMQJi9JPsCD20w= X-Stat-Signature: zybm6c1axdi16tud5x6eqz7uykzruoso X-Rspamd-Queue-Id: B2C11C0007 X-Rspamd-Server: rspam08 X-Rspam-User: Authentication-Results: imf22.hostedemail.com; dkim=none; spf=pass (imf22.hostedemail.com: domain of liuzixian4@huawei.com designates 45.249.212.189 as permitted sender) smtp.mailfrom=liuzixian4@huawei.com; dmarc=pass (policy=quarantine) header.from=huawei.com X-HE-Tag: 1658842110-248187 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: Thank you for you review! I've sent a v2 patch to remove prep_transhuge_page. >That's intentional. Possibly misguided, but there's a tradeoff to be made between memory consumption and using large pages. Our tmpfs users have seen a ~5% performance degradation after hotpatch, and they think its unacceptable.