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 X-Spam-Level: X-Spam-Status: No, score=-15.1 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id EBFE4C433ED for ; Tue, 18 May 2021 11:29:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id CD087611BD for ; Tue, 18 May 2021 11:29:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S244881AbhERLbO (ORCPT ); Tue, 18 May 2021 07:31:14 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41910 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1348223AbhERLbK (ORCPT ); Tue, 18 May 2021 07:31:10 -0400 Received: from pandora.armlinux.org.uk (pandora.armlinux.org.uk [IPv6:2001:4d48:ad52:32c8:5054:ff:fe00:142]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C13B5C06138B for ; Tue, 18 May 2021 04:29:51 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=armlinux.org.uk; s=pandora-2019; h=Sender:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=RVUhSCgd6iQAK0YSfHil0g0540QhJdzDOaZHYw4efBo=; b=tl66YL0JYskY6r9w4wyuz1msm 2nN5acglOY9mroY2uRDEigtHcNw/lxmbReo/GR0Wt8VyC5ni7zKmpRaOJLOCpfgK/dxHXOUIL5tCq aGcRVwrUs7lIyjwTfFnao1fs88QDm9YEdiHycchb9PR+GFUC1YH2UDApAY2ZT8SvG/z9PncAvC6Zp kZIL+XLsXuZroU2QD/0o93SjzghJ1ilf3PGOjpTy4b7OIhJYnRvzicYZQqZMJcjfL32lzzLH9ul/p otEiCDS+/fseB8D12RJcshFcL8vwUt2lQD8UdU5aY2WC3ZoQ7Ebs/yDoK5aYREWJ3OA6nFBvVCdEq QYEjvkmBw==; Received: from shell.armlinux.org.uk ([fd8f:7570:feb6:1:5054:ff:fe00:4ec]:44130) by pandora.armlinux.org.uk with esmtpsa (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1lixuq-0004B6-8m; Tue, 18 May 2021 12:29:36 +0100 Received: from linux by shell.armlinux.org.uk with local (Exim 4.92) (envelope-from ) id 1lixum-0007r3-6a; Tue, 18 May 2021 12:29:32 +0100 Date: Tue, 18 May 2021 12:29:32 +0100 From: "Russell King (Oracle)" To: Yanfei Xu Cc: rppt@kernel.org, ardb@kernel.org, linus.walleij@linaro.org, akpm@linux-foundation.org, carver4lio@163.com, tiantao6@hisilicon.com, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] arm: make the size of vmalloc in cmdline and meminfo uniform Message-ID: <20210518112932.GV12395@shell.armlinux.org.uk> References: <20210518111254.3820480-1-yanfei.xu@windriver.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210518111254.3820480-1-yanfei.xu@windriver.com> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: Russell King (Oracle) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, May 18, 2021 at 07:12:54PM +0800, Yanfei Xu wrote: > The value of "vmalloc=" set in cmdline is always 8M more than the value > of "VmallocTotal" in meminfo. When use the "vmalloc=" parameter, user > expect to get the size what they input, and no need to consider the 8M > "hole" hided in codes. This commit make real vmalloc size equal to value > of "vmalloc=" in cmdline. > > Also, the commit will reduce the size of vmalloc printed in boot message > by 8M when the size set in cmdline is irrational. Hi, I think I'd like to do several cleanups with this: 1. change vmalloc_min to be an unsigned long. 2. exclude VMALLOC_OFFSET from vmalloc_min, moving it into adjust_lowmem_bounds where vmalloc_min is used. 3. rename vmalloc_min to be vmalloc_start 4. enforce vmalloc_start to be a multiple of 2MiB 5. in early_vmalloc(), calculate vmalloc_max as: VMALLOC_END - (PAGE_OFFSET + SZ_32M + VMALLOC_OFFSET) and use that to set the upper bound of vmalloc_reserve (which is something your patch doesn't do, which I think is a bug. Thoughts? > > Signed-off-by: Yanfei Xu > --- > arch/arm/mm/mmu.c | 9 +++++---- > 1 file changed, 5 insertions(+), 4 deletions(-) > > diff --git a/arch/arm/mm/mmu.c b/arch/arm/mm/mmu.c > index c1e12aab67b8..287c5115af4d 100644 > --- a/arch/arm/mm/mmu.c > +++ b/arch/arm/mm/mmu.c > @@ -1133,19 +1133,20 @@ static int __init early_vmalloc(char *arg) > { > unsigned long vmalloc_reserve = memparse(arg, NULL); > > - if (vmalloc_reserve < SZ_16M) { > - vmalloc_reserve = SZ_16M; > + vmalloc_reserve = ALIGN_DOWN(vmalloc_reserve, SZ_8M); > + if (vmalloc_reserve < SZ_8M) { > + vmalloc_reserve = SZ_8M; > pr_warn("vmalloc area too small, limiting to %luMB\n", > vmalloc_reserve >> 20); > } > > if (vmalloc_reserve > VMALLOC_END - (PAGE_OFFSET + SZ_32M)) { > - vmalloc_reserve = VMALLOC_END - (PAGE_OFFSET + SZ_32M); > + vmalloc_reserve = VMALLOC_END - (PAGE_OFFSET + SZ_32M + VMALLOC_OFFSET); > pr_warn("vmalloc area is too big, limiting to %luMB\n", > vmalloc_reserve >> 20); > } > > - vmalloc_min = (void *)(VMALLOC_END - vmalloc_reserve); > + vmalloc_min = (void *)(VMALLOC_END - vmalloc_reserve - VMALLOC_OFFSET); > return 0; > } > early_param("vmalloc", early_vmalloc); > -- > 2.27.0 > > > _______________________________________________ > linux-arm-kernel mailing list > linux-arm-kernel@lists.infradead.org > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel > -- RMK's Patch system: https://www.armlinux.org.uk/developer/patches/ FTTP is here! 40Mbps down 10Mbps up. Decent connectivity at last!