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=-15.0 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,RDNS_NONE,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (unknown [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 03F8CC433C1 for ; Sun, 21 Mar 2021 03:38:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C3D2560238 for ; Sun, 21 Mar 2021 03:38:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229986AbhCUDhy (ORCPT ); Sat, 20 Mar 2021 23:37:54 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51888 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229805AbhCUDhp (ORCPT ); Sat, 20 Mar 2021 23:37:45 -0400 Received: from mail-pg1-x534.google.com (mail-pg1-x534.google.com [IPv6:2607:f8b0:4864:20::534]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B6052C061574 for ; Sat, 20 Mar 2021 20:37:44 -0700 (PDT) Received: by mail-pg1-x534.google.com with SMTP id v2so6376199pgk.11 for ; Sat, 20 Mar 2021 20:37:44 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=UO8rbq0+kqRaTjZw3G4nKUjHlHbuRA+XYvccxPC+8fc=; b=F/gnec5pQX2xPdlwo2ptR3vuUqplHpKTaIO68mwzbh1cLT9S5vyjyj08b0hRdo0fRA aPtC7T0rehITzUswqexVYYN0otPWzeAxny8FkEto7wxipNyEAKF4eswwy3I0CG8iolK0 cVXzk0jVFN8xxuMZ8QEN11/XL7dOT2XR7ymXY44vQwdIxyeQlHTfGEuNn8Zm1s5Jx1A9 iD5KEWqU8G3BUUH+/AkgeQQstXMCcHkYrgnDb7qJWjAelFPq+0eK9CtgYrtvGixyiJtv 0/AV14nSrgUD6e2OmOwfpA8NlGIrIUHNRGx97eQe3s6Xy9/S8iXtWGVa/Q7ddfM3qNuu nCTg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=UO8rbq0+kqRaTjZw3G4nKUjHlHbuRA+XYvccxPC+8fc=; b=LLaQ1lNJdNpIcNtKsj/4YaC2d8pZGlUPCzlo3iRPAHuPfFw5KPGUxszHP5BvDv2yjy Ewl6iomPBuc6r939849ZoTH2aFhZybZd5bG4hixS9cJ/281LC27ZS0M3/oDtkYschxk8 KbWZztC47LTydIoxUJSeiMmkJGHrbiPu+n6YvpRPaQVDiFYzEfb+cEdBx1AhP+0ZbeH+ wHBiPhWwkrrT4c3ZYDFtCEwYVINr9UfBTIX4uzW7q4MsEs44NVnkko9bU93ACEm1nXQx ZwdYDNy8VlSjVCVh/nUUYmzZyGMirElcWSEdZquNm7M7LcyuuSrogr1IvBKbksDZqypC W8Zw== X-Gm-Message-State: AOAM532hHc7Tvhj6q3/WdcCO4DuSYvv+v1UQo3ZwNeH4fffF62nAl7tb J6X8G3dsT04Pg4rfqwa/H9H/lY/WE5U= X-Google-Smtp-Source: ABdhPJymdtdqAVJYxOk6uVcvorM3cCBvr0inWwlQnN2ca5LzxTGnat1XqW/aqiGOwRQEEs76gkjl9A== X-Received: by 2002:aa7:9394:0:b029:1f4:2b30:4cdb with SMTP id t20-20020aa793940000b02901f42b304cdbmr16213688pfe.50.1616297863405; Sat, 20 Mar 2021 20:37:43 -0700 (PDT) Received: from fainelli-desktop.igp.broadcom.net ([192.19.223.252]) by smtp.gmail.com with ESMTPSA id l190sm9708422pfl.73.2021.03.20.20.37.42 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sat, 20 Mar 2021 20:37:42 -0700 (PDT) From: Florian Fainelli To: linux-kernel@vger.kernel.org Cc: Florian Fainelli , Konrad Rzeszutek Wilk , Christoph Hellwig , Marek Szyprowski , Robin Murphy , iommu@lists.linux-foundation.org (open list:SWIOTLB SUBSYSTEM) Subject: [PATCH v2] swiotlb: Make SWIOTLB_NO_FORCE perform no allocation Date: Sat, 20 Mar 2021 20:37:40 -0700 Message-Id: <20210321033740.312500-1-f.fainelli@gmail.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20210319040055.183433-1-f.fainelli@gmail.com> References: <20210319040055.183433-1-f.fainelli@gmail.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org When SWIOTLB_NO_FORCE is used, there should really be no allocations of default_nslabs to occur since we are not going to use those slabs. If a platform was somehow setting swiotlb_no_force and a later call to swiotlb_init() was to be made we would still be proceeding with allocating the default SWIOTLB size (64MB), whereas if swiotlb=noforce was set on the kernel command line we would have only allocated 2KB. This would be inconsistent and the point of initializing default_nslabs to 1, was intended to allocate the minimum amount of memory possible, so simply remove that minimal allocation period. Signed-off-by: Florian Fainelli --- Changes in v2: - rebased against devel/for-linus-5.13 - updated commit message to reflect variable names kernel/dma/swiotlb.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c index 539c76beb52e..d20002a61546 100644 --- a/kernel/dma/swiotlb.c +++ b/kernel/dma/swiotlb.c @@ -83,12 +83,10 @@ setup_io_tlb_npages(char *str) } if (*str == ',') ++str; - if (!strcmp(str, "force")) { + if (!strcmp(str, "force")) swiotlb_force = SWIOTLB_FORCE; - } else if (!strcmp(str, "noforce")) { + else if (!strcmp(str, "noforce")) swiotlb_force = SWIOTLB_NO_FORCE; - default_nslabs = 1; - } return 0; } @@ -211,6 +209,9 @@ swiotlb_init(int verbose) size_t bytes = PAGE_ALIGN(default_nslabs << IO_TLB_SHIFT); void *tlb; + if (swiotlb_force == SWIOTLB_NO_FORCE) + return; + /* Get IO TLB memory from the low pages */ tlb = memblock_alloc_low(bytes, PAGE_SIZE); if (!tlb) -- 2.25.1