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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1451BC433F5 for ; Wed, 19 Jan 2022 13:48:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1354909AbiASNsW (ORCPT ); Wed, 19 Jan 2022 08:48:22 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35530 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1349591AbiASNsV (ORCPT ); Wed, 19 Jan 2022 08:48:21 -0500 Received: from casper.infradead.org (casper.infradead.org [IPv6:2001:8b0:10b:1236::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id BE51CC061574; Wed, 19 Jan 2022 05:48:20 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=In-Reply-To:Content-Transfer-Encoding: Content-Type:MIME-Version:References:Message-ID:Subject:Cc:To:From:Date: Sender:Reply-To:Content-ID:Content-Description; bh=KXtnBmHR26VnyA5/MyeO0p5Mer/FOttvLvx2Yg5H/f0=; b=q307KYxlizBZChDxVWf50BNc7i ulkozYxgvKy0JvUzcELQya+co3ae/kHNFbO1y3/T6S4j4u1q9n27AiQpeEc9GpLDMLSVvksmQpPJK MnOEHc+PxkQY8WS6RXMiDj04z27Jr9OmVBz/rv0fcvN4azhZg8dQVHcGy+WMroOnLK3bySxG5A+xI LWqXJF+Jr7gv+tHXgGkVDEIF2ha516o0dx4gsz6ldb3tNDDk3wMbKx6lT5M3fygBiU12ICmzCpzXc 3HIhEJKLOdRJ6XLNvaHagY1xzR38gvmSE8gEDYjtJuNOqUATZ+WipQz+OHME+/GVUHEcyAgphvSQK QIPa9SLA==; Received: from willy by casper.infradead.org with local (Exim 4.94.2 #2 (Red Hat Linux)) id 1nABJt-00AwLk-Qj; Wed, 19 Jan 2022 13:48:13 +0000 Date: Wed, 19 Jan 2022 13:48:13 +0000 From: Matthew Wilcox To: Kefeng Wang Cc: Nicholas Piggin , Andrew Morton , Jonathan Corbet , linux-arm-kernel@lists.infradead.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, linuxppc-dev@lists.ozlabs.org, x86@kernel.org, Benjamin Herrenschmidt , Borislav Petkov , Catalin Marinas , Christophe Leroy , Dave Hansen , "H. Peter Anvin" , Ingo Molnar , Michael Ellerman , Paul Mackerras , Thomas Gleixner , Will Deacon Subject: Re: [PATCH v2 1/3] mm: vmalloc: Let user to control huge vmalloc default behavior Message-ID: References: <20211227145903.187152-1-wangkefeng.wang@huawei.com> <20211227145903.187152-2-wangkefeng.wang@huawei.com> <1642473992.qrnqczjfna.astroid@bobo.none> <93db576e-9a62-ee98-5af2-a62f8386212c@huawei.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <93db576e-9a62-ee98-5af2-a62f8386212c@huawei.com> Precedence: bulk List-ID: X-Mailing-List: linux-doc@vger.kernel.org On Wed, Jan 19, 2022 at 09:44:20PM +0800, Kefeng Wang wrote: > > On 2022/1/19 21:22, Matthew Wilcox wrote: > > On Wed, Jan 19, 2022 at 08:57:58PM +0800, Kefeng Wang wrote: > > > Only parts of our products wants this feature,  we add some interfaces which > > > only > > > > > > alloc hugevmalloc for them, eg, > > > vmap_hugepage/vmalloc_hugepage/remap_vmalloc_hugepage_range.. > > > > > > for our products, but it's not the choice of most products, also add > > > nohugevmalloc > > > > > > for most products is expensive, so this is the reason for adding the patch. > > > > > > more config/cmdline are more flexible for test/products， > > But why do only some products want it? What goes wrong if all products > > enable it? Features should be auto-tuning, not relying on admins to > > understand them. > > Because this feature will use more memory for vmalloc/vmap, that's why we > add some explicit > interfaces as said above in our kernel to control the user. Have you validated that? What sort of performance penalty do you see? 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 lists.ozlabs.org (lists.ozlabs.org [112.213.38.117]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id B8195C433F5 for ; Wed, 19 Jan 2022 13:49:07 +0000 (UTC) Received: from boromir.ozlabs.org (localhost [IPv6:::1]) by lists.ozlabs.org (Postfix) with ESMTP id 4Jf6SL1d73z3bbR for ; Thu, 20 Jan 2022 00:49:06 +1100 (AEDT) Authentication-Results: lists.ozlabs.org; dkim=fail reason="signature verification failed" (2048-bit key; secure) header.d=infradead.org header.i=@infradead.org header.a=rsa-sha256 header.s=casper.20170209 header.b=q307KYxl; dkim-atps=neutral Authentication-Results: lists.ozlabs.org; spf=none (no SPF record) smtp.mailfrom=infradead.org (client-ip=2001:8b0:10b:1236::1; helo=casper.infradead.org; envelope-from=willy@infradead.org; receiver=) Authentication-Results: lists.ozlabs.org; dkim=pass (2048-bit key; secure) header.d=infradead.org header.i=@infradead.org header.a=rsa-sha256 header.s=casper.20170209 header.b=q307KYxl; dkim-atps=neutral Received: from casper.infradead.org (casper.infradead.org [IPv6:2001:8b0:10b:1236::1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 4Jf6RZ0BGFz2xv0 for ; Thu, 20 Jan 2022 00:48:25 +1100 (AEDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=In-Reply-To:Content-Transfer-Encoding: Content-Type:MIME-Version:References:Message-ID:Subject:Cc:To:From:Date: Sender:Reply-To:Content-ID:Content-Description; bh=KXtnBmHR26VnyA5/MyeO0p5Mer/FOttvLvx2Yg5H/f0=; b=q307KYxlizBZChDxVWf50BNc7i ulkozYxgvKy0JvUzcELQya+co3ae/kHNFbO1y3/T6S4j4u1q9n27AiQpeEc9GpLDMLSVvksmQpPJK MnOEHc+PxkQY8WS6RXMiDj04z27Jr9OmVBz/rv0fcvN4azhZg8dQVHcGy+WMroOnLK3bySxG5A+xI LWqXJF+Jr7gv+tHXgGkVDEIF2ha516o0dx4gsz6ldb3tNDDk3wMbKx6lT5M3fygBiU12ICmzCpzXc 3HIhEJKLOdRJ6XLNvaHagY1xzR38gvmSE8gEDYjtJuNOqUATZ+WipQz+OHME+/GVUHEcyAgphvSQK QIPa9SLA==; Received: from willy by casper.infradead.org with local (Exim 4.94.2 #2 (Red Hat Linux)) id 1nABJt-00AwLk-Qj; Wed, 19 Jan 2022 13:48:13 +0000 Date: Wed, 19 Jan 2022 13:48:13 +0000 From: Matthew Wilcox To: Kefeng Wang Subject: Re: [PATCH v2 1/3] mm: vmalloc: Let user to control huge vmalloc default behavior Message-ID: References: <20211227145903.187152-1-wangkefeng.wang@huawei.com> <20211227145903.187152-2-wangkefeng.wang@huawei.com> <1642473992.qrnqczjfna.astroid@bobo.none> <93db576e-9a62-ee98-5af2-a62f8386212c@huawei.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <93db576e-9a62-ee98-5af2-a62f8386212c@huawei.com> X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: x86@kernel.org, "H. Peter Anvin" , Dave Hansen , linux-doc@vger.kernel.org, Jonathan Corbet , linux-kernel@vger.kernel.org, Nicholas Piggin , linux-mm@kvack.org, Will Deacon , Ingo Molnar , Borislav Petkov , Catalin Marinas , Paul Mackerras , Andrew Morton , linuxppc-dev@lists.ozlabs.org, Thomas Gleixner , linux-arm-kernel@lists.infradead.org Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" On Wed, Jan 19, 2022 at 09:44:20PM +0800, Kefeng Wang wrote: > > On 2022/1/19 21:22, Matthew Wilcox wrote: > > On Wed, Jan 19, 2022 at 08:57:58PM +0800, Kefeng Wang wrote: > > > Only parts of our products wants this feature,  we add some interfaces which > > > only > > > > > > alloc hugevmalloc for them, eg, > > > vmap_hugepage/vmalloc_hugepage/remap_vmalloc_hugepage_range.. > > > > > > for our products, but it's not the choice of most products, also add > > > nohugevmalloc > > > > > > for most products is expensive, so this is the reason for adding the patch. > > > > > > more config/cmdline are more flexible for test/products， > > But why do only some products want it? What goes wrong if all products > > enable it? Features should be auto-tuning, not relying on admins to > > understand them. > > Because this feature will use more memory for vmalloc/vmap, that's why we > add some explicit > interfaces as said above in our kernel to control the user. Have you validated that? What sort of performance penalty do you see? 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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 7C6ACC433F5 for ; Wed, 19 Jan 2022 13:49:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:Cc:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=Zw/ouTCskqpJJGpGtpsIGfcaelR/r9V8Jqypf4xVtgk=; b=WgRrxp+k4XQAQY yHjktlEny0FEp4QvaAx2n8jxktjTsLp6vZm631LtbCFm7gwBflZqBTU4+BPMlnRelNqo/rA8v61SI edBd0P5kca1VBdBzU6YARRIjdqzaiBn2jmT9no76hl7IqrgSg9GFoGdxMSBP104JJBb7zK+T2fdhI 8UflCKM/Xcpbxd93EufMRqMBeuDX/dDgYpAT1ErYa7EpaoI+NXk0D9jfDa0d5iaaTnolcMrNqaz+c LgYnquW1fj1mm/ExSNV+Hp2SInQkYPpNzc0fZckubJaKqRvzrnKXxwP2x7+vnHFu8NMd2qn1Rt8gV RB68WBbCQ109SCttFSmw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1nABJz-005jdn-LK; Wed, 19 Jan 2022 13:48:20 +0000 Received: from casper.infradead.org ([2001:8b0:10b:1236::1]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1nABJv-005jcP-U5 for linux-arm-kernel@bombadil.infradead.org; Wed, 19 Jan 2022 13:48:15 +0000 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=In-Reply-To:Content-Transfer-Encoding: Content-Type:MIME-Version:References:Message-ID:Subject:Cc:To:From:Date: Sender:Reply-To:Content-ID:Content-Description; bh=KXtnBmHR26VnyA5/MyeO0p5Mer/FOttvLvx2Yg5H/f0=; b=q307KYxlizBZChDxVWf50BNc7i ulkozYxgvKy0JvUzcELQya+co3ae/kHNFbO1y3/T6S4j4u1q9n27AiQpeEc9GpLDMLSVvksmQpPJK MnOEHc+PxkQY8WS6RXMiDj04z27Jr9OmVBz/rv0fcvN4azhZg8dQVHcGy+WMroOnLK3bySxG5A+xI LWqXJF+Jr7gv+tHXgGkVDEIF2ha516o0dx4gsz6ldb3tNDDk3wMbKx6lT5M3fygBiU12ICmzCpzXc 3HIhEJKLOdRJ6XLNvaHagY1xzR38gvmSE8gEDYjtJuNOqUATZ+WipQz+OHME+/GVUHEcyAgphvSQK QIPa9SLA==; Received: from willy by casper.infradead.org with local (Exim 4.94.2 #2 (Red Hat Linux)) id 1nABJt-00AwLk-Qj; Wed, 19 Jan 2022 13:48:13 +0000 Date: Wed, 19 Jan 2022 13:48:13 +0000 From: Matthew Wilcox To: Kefeng Wang Cc: Nicholas Piggin , Andrew Morton , Jonathan Corbet , linux-arm-kernel@lists.infradead.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, linuxppc-dev@lists.ozlabs.org, x86@kernel.org, Benjamin Herrenschmidt , Borislav Petkov , Catalin Marinas , Christophe Leroy , Dave Hansen , "H. Peter Anvin" , Ingo Molnar , Michael Ellerman , Paul Mackerras , Thomas Gleixner , Will Deacon Subject: Re: [PATCH v2 1/3] mm: vmalloc: Let user to control huge vmalloc default behavior Message-ID: References: <20211227145903.187152-1-wangkefeng.wang@huawei.com> <20211227145903.187152-2-wangkefeng.wang@huawei.com> <1642473992.qrnqczjfna.astroid@bobo.none> <93db576e-9a62-ee98-5af2-a62f8386212c@huawei.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <93db576e-9a62-ee98-5af2-a62f8386212c@huawei.com> X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org T24gV2VkLCBKYW4gMTksIDIwMjIgYXQgMDk6NDQ6MjBQTSArMDgwMCwgS2VmZW5nIFdhbmcgd3Jv dGU6Cj4gCj4gT24gMjAyMi8xLzE5IDIxOjIyLCBNYXR0aGV3IFdpbGNveCB3cm90ZToKPiA+IE9u IFdlZCwgSmFuIDE5LCAyMDIyIGF0IDA4OjU3OjU4UE0gKzA4MDAsIEtlZmVuZyBXYW5nIHdyb3Rl Ogo+ID4gPiBPbmx5IHBhcnRzIG9mIG91ciBwcm9kdWN0cyB3YW50cyB0aGlzIGZlYXR1cmUswqAg d2UgYWRkIHNvbWUgaW50ZXJmYWNlcyB3aGljaAo+ID4gPiBvbmx5Cj4gPiA+IAo+ID4gPiBhbGxv YyBodWdldm1hbGxvYyBmb3IgdGhlbSwgZWcsCj4gPiA+IHZtYXBfaHVnZXBhZ2Uvdm1hbGxvY19o dWdlcGFnZS9yZW1hcF92bWFsbG9jX2h1Z2VwYWdlX3JhbmdlLi4KPiA+ID4gCj4gPiA+IGZvciBv dXIgcHJvZHVjdHMsIGJ1dCBpdCdzIG5vdCB0aGUgY2hvaWNlIG9mIG1vc3QgcHJvZHVjdHMsIGFs c28gYWRkCj4gPiA+IG5vaHVnZXZtYWxsb2MKPiA+ID4gCj4gPiA+IGZvciBtb3N0IHByb2R1Y3Rz IGlzIGV4cGVuc2l2ZSwgc28gdGhpcyBpcyB0aGUgcmVhc29uIGZvciBhZGRpbmcgdGhlIHBhdGNo Lgo+ID4gPiAKPiA+ID4gbW9yZSBjb25maWcvY21kbGluZSBhcmUgbW9yZSBmbGV4aWJsZSBmb3Ig dGVzdC9wcm9kdWN0c++8jAo+ID4gQnV0IHdoeSBkbyBvbmx5IHNvbWUgcHJvZHVjdHMgd2FudCBp dD8gIFdoYXQgZ29lcyB3cm9uZyBpZiBhbGwgcHJvZHVjdHMKPiA+IGVuYWJsZSBpdD8gIEZlYXR1 cmVzIHNob3VsZCBiZSBhdXRvLXR1bmluZywgbm90IHJlbHlpbmcgb24gYWRtaW5zIHRvCj4gPiB1 bmRlcnN0YW5kIHRoZW0uCj4gCj4gQmVjYXVzZSB0aGlzIGZlYXR1cmUgd2lsbCB1c2UgbW9yZSBt ZW1vcnkgZm9yIHZtYWxsb2Mvdm1hcCwgdGhhdCdzIHdoeSB3ZQo+IGFkZCBzb21lIGV4cGxpY2l0 Cj4gaW50ZXJmYWNlcyBhcyBzYWlkIGFib3ZlIGluIG91ciBrZXJuZWwgdG8gY29udHJvbCB0aGUg dXNlci4KCkhhdmUgeW91IHZhbGlkYXRlZCB0aGF0PyAgV2hhdCBzb3J0IG9mIHBlcmZvcm1hbmNl IHBlbmFsdHkgZG8geW91IHNlZT8KCl9fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19f X19fX19fX19fX19fCmxpbnV4LWFybS1rZXJuZWwgbWFpbGluZyBsaXN0CmxpbnV4LWFybS1rZXJu ZWxAbGlzdHMuaW5mcmFkZWFkLm9yZwpodHRwOi8vbGlzdHMuaW5mcmFkZWFkLm9yZy9tYWlsbWFu L2xpc3RpbmZvL2xpbnV4LWFybS1rZXJuZWwK