From mboxrd@z Thu Jan 1 00:00:00 1970 Received: with ECARTIS (v1.0.0; list linux-mips); Tue, 08 Dec 2015 13:12:58 +0100 (CET) Received: from mail-lb0-f180.google.com ([209.85.217.180]:33397 "EHLO mail-lb0-f180.google.com" rhost-flags-OK-OK-OK-OK) by eddie.linux-mips.org with ESMTP id S27013349AbbLHMMzyk8XF (ORCPT ); Tue, 8 Dec 2015 13:12:55 +0100 Received: by lbbkw15 with SMTP id kw15so9940718lbb.0 for ; Tue, 08 Dec 2015 04:12:50 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=cogentembedded-com.20150623.gappssmtp.com; s=20150623; h=subject:to:references:cc:from:message-id:date:user-agent :mime-version:in-reply-to:content-type:content-transfer-encoding; bh=cJtjFMSL7fYh6MKDObHyP5f7I+1M7M08qZiUyZycCEw=; b=O4NEzNOtYVIpaisu5VV5TfggmC5ShKFDeDdSOb/sMmbjjho3M67i7BoYdES+O4GBNT pe8dse7WIx21XHhH+j4d3oXFx8na4iEeiXsGWMrXd3+jdeQIwOZTBcYwPoKRxRX3XXFS TczrjCQixsSD5e1pU0Vw3Bv8UtRFCzyIjYw66CEBTUvFEj8KIYM9cAEf18S0WASZi58A sVuxHjrfLirh7whuwvmOugsQKubb0MjkdgXYmVK1MKKBNV596ZTBCb3qydlKa41bxdIO bKZUQSFohnZPeSoFp3jAJy3mFcKyZx175/P78PQHQNFDuULueq1x0OnIWUh5LLmyvftY ZhBQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:subject:to:references:cc:from:message-id:date :user-agent:mime-version:in-reply-to:content-type :content-transfer-encoding; bh=cJtjFMSL7fYh6MKDObHyP5f7I+1M7M08qZiUyZycCEw=; b=EP8LMPwTFCMfwYSNFGGzcjlNTf4L230FVCakUgjUnoXadWlAscQJNha9tNxuNlR0I+ ceju+GLo/yq6lJWmDFvoeF905Z0QU5HK2JmV4sJ0OP9ArH/ylqLGR6r9XYVFDFAiH9cT zyTdhnNNUR8mmcJTHYPTsIGpb8ZVxomC29VGQcezFwmOrxm9ZqGWPrBeuv8Amt1piR02 f1VcunqxhoaboQ19sVQqJOlA4HyrbRqAIagx9XvO0MFCsxuYjd0XSTKqrh5sFapOvYYh wjtkmoNnGpDDeQ7DJsBcoButuhz9B7/wR9/IN6Zyxa4U0b4wl9PcyR4zEg0tQNMTd9lI toaA== X-Gm-Message-State: ALoCoQn8tvjv2SsBy7/XEhFRA7+0I5vLYMCW3NWa2YKgWPcECX7B7denDlg8QfgythqAZ4H40L35/CiZjIPu8Zn6loacVpk2zg== X-Received: by 10.112.146.42 with SMTP id sz10mr1326370lbb.50.1449576770533; Tue, 08 Dec 2015 04:12:50 -0800 (PST) Received: from [192.168.4.126] ([83.149.8.57]) by smtp.gmail.com with ESMTPSA id um1sm527346lbb.23.2015.12.08.04.12.49 (version=TLSv1/SSLv3 cipher=OTHER); Tue, 08 Dec 2015 04:12:49 -0800 (PST) Subject: Re: [PATCH] MIPS: Fix DMA contiguous allocation To: Qais Yousef , linux-mips@linux-mips.org References: <1449569930-2118-1-git-send-email-qais.yousef@imgtec.com> Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, ralf@linux-mips.org, akpm@linux-foundation.org, mgorman@techsingularity.net From: Sergei Shtylyov Message-ID: <5666C941.20209@cogentembedded.com> Date: Tue, 8 Dec 2015 15:12:49 +0300 User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:38.0) Gecko/20100101 Thunderbird/38.4.0 MIME-Version: 1.0 In-Reply-To: <1449569930-2118-1-git-send-email-qais.yousef@imgtec.com> Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Return-Path: X-Envelope-To: <"|/home/ecartis/ecartis -s linux-mips"> (uid 0) X-Orcpt: rfc822;linux-mips@linux-mips.org Original-Recipient: rfc822;linux-mips@linux-mips.org X-archive-position: 50421 X-ecartis-version: Ecartis v1.0.0 Sender: linux-mips-bounce@linux-mips.org Errors-to: linux-mips-bounce@linux-mips.org X-original-sender: sergei.shtylyov@cogentembedded.com Precedence: bulk List-help: List-unsubscribe: List-software: Ecartis version 1.0.0 List-Id: linux-mips X-List-ID: linux-mips List-subscribe: List-owner: List-post: List-archive: X-list: linux-mips On 12/8/2015 1:18 PM, Qais Yousef wrote: > Recent changes to how GFP_ATOMIC is defined seems to have broken the condition > to use mips_alloc_from_contiguous() in mips_dma_alloc_coherent(). > > I couldn't bottom out the exact change but I think it's this one > > d0164adc89f6 (mm, page_alloc: distinguish between being unable to sleep, > unwilling to sleep and avoiding waking kswapd) > > From what I see GFP_ATOMIC has multiple bits set and the check for !(gfp > & GFP_ATOMIC) isn't enough. To verify if the flag is atomic we need to make > sure that (gfp & GFP_ATOMIC) == GFP_ATOMIC to verify that all bits rquired to Required. > satisfy GFP_ATOMIC condition are set. > > Signed-off-by: Qais Yousef > --- > arch/mips/mm/dma-default.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/arch/mips/mm/dma-default.c b/arch/mips/mm/dma-default.c > index d8117be729a2..d6b8a1445a3a 100644 > --- a/arch/mips/mm/dma-default.c > +++ b/arch/mips/mm/dma-default.c > @@ -145,7 +145,7 @@ static void *mips_dma_alloc_coherent(struct device *dev, size_t size, > > gfp = massage_gfp_flags(dev, gfp); > > - if (IS_ENABLED(CONFIG_DMA_CMA) && !(gfp & GFP_ATOMIC)) > + if (IS_ENABLED(CONFIG_DMA_CMA) && ((gfp & GFP_ATOMIC) != GFP_ATOMIC)) () around != not necessary. [...] MBR, Sergei From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-lb0-f179.google.com (mail-lb0-f179.google.com [209.85.217.179]) by kanga.kvack.org (Postfix) with ESMTP id 0FB126B0038 for ; Tue, 8 Dec 2015 07:12:52 -0500 (EST) Received: by lbblt2 with SMTP id lt2so9913002lbb.3 for ; Tue, 08 Dec 2015 04:12:51 -0800 (PST) Received: from mail-lb0-x22c.google.com (mail-lb0-x22c.google.com. [2a00:1450:4010:c04::22c]) by mx.google.com with ESMTPS id 40si1534818lfq.17.2015.12.08.04.12.50 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 08 Dec 2015 04:12:50 -0800 (PST) Received: by lbbcs9 with SMTP id cs9so9888135lbb.1 for ; Tue, 08 Dec 2015 04:12:50 -0800 (PST) Subject: Re: [PATCH] MIPS: Fix DMA contiguous allocation References: <1449569930-2118-1-git-send-email-qais.yousef@imgtec.com> From: Sergei Shtylyov Message-ID: <5666C941.20209@cogentembedded.com> Date: Tue, 8 Dec 2015 15:12:49 +0300 MIME-Version: 1.0 In-Reply-To: <1449569930-2118-1-git-send-email-qais.yousef@imgtec.com> Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Qais Yousef , linux-mips@linux-mips.org Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, ralf@linux-mips.org, akpm@linux-foundation.org, mgorman@techsingularity.net On 12/8/2015 1:18 PM, Qais Yousef wrote: > Recent changes to how GFP_ATOMIC is defined seems to have broken the condition > to use mips_alloc_from_contiguous() in mips_dma_alloc_coherent(). > > I couldn't bottom out the exact change but I think it's this one > > d0164adc89f6 (mm, page_alloc: distinguish between being unable to sleep, > unwilling to sleep and avoiding waking kswapd) > > From what I see GFP_ATOMIC has multiple bits set and the check for !(gfp > & GFP_ATOMIC) isn't enough. To verify if the flag is atomic we need to make > sure that (gfp & GFP_ATOMIC) == GFP_ATOMIC to verify that all bits rquired to Required. > satisfy GFP_ATOMIC condition are set. > > Signed-off-by: Qais Yousef > --- > arch/mips/mm/dma-default.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/arch/mips/mm/dma-default.c b/arch/mips/mm/dma-default.c > index d8117be729a2..d6b8a1445a3a 100644 > --- a/arch/mips/mm/dma-default.c > +++ b/arch/mips/mm/dma-default.c > @@ -145,7 +145,7 @@ static void *mips_dma_alloc_coherent(struct device *dev, size_t size, > > gfp = massage_gfp_flags(dev, gfp); > > - if (IS_ENABLED(CONFIG_DMA_CMA) && !(gfp & GFP_ATOMIC)) > + if (IS_ENABLED(CONFIG_DMA_CMA) && ((gfp & GFP_ATOMIC) != GFP_ATOMIC)) () around != not necessary. [...] MBR, Sergei -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org