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=-15.8 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,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable 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 F339BC433DB for ; Tue, 23 Mar 2021 01:54:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id BEB28619A8 for ; Tue, 23 Mar 2021 01:54:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229804AbhCWByW (ORCPT ); Mon, 22 Mar 2021 21:54:22 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55638 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229472AbhCWBxx (ORCPT ); Mon, 22 Mar 2021 21:53:53 -0400 Received: from mail-pg1-x52d.google.com (mail-pg1-x52d.google.com [IPv6:2607:f8b0:4864:20::52d]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id BA03BC061574 for ; Mon, 22 Mar 2021 18:53:53 -0700 (PDT) Received: by mail-pg1-x52d.google.com with SMTP id v2so10135380pgk.11 for ; Mon, 22 Mar 2021 18:53:53 -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=UN25kkS2KebRuu15wRF3YovKapnV4LybmIZMwea2YYo=; b=X4Hl65Vht8ypMH0BrR0aS/wzxgY9EdKWM8THL1iBDBWDVa03DGOeOvbQqxUp2Qlfr0 LCivPy5VLWfs8Gz9CxuhYn5VzH6AB9vifmRKFmoakKCvnDTDv9e9ri6mU87ekvCqn8vB waPxprwZ3hVctrMPlk2o4AgKEm/KOVAqxZ4PIJ2h6645pCiMNEGzhqvc04g59k5Rzw2r LYh+Apd6aQNlfwW5KUMCm8wLJUMZhXgDcGL+VG9iyvBbYKiSJyPmSVUNe1dOc7UJY1ZB tXu/y/Hnyfa7DY5P1e3aO123voc/qDI6fNDlvCdzPn76uA0Y2NNejeoNZHSequ1NIn87 jIYg== 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=UN25kkS2KebRuu15wRF3YovKapnV4LybmIZMwea2YYo=; b=P/WB9hCgWeriWDbCaiaBCD0SipNUXx+1BEqL2mvNuNHWbnHWJ1i1A00vydG7cxeB0s Dpi7u1aBWSQgID2uMhQXQKrKLEFN5lPD3G/M62mWoLsUc/ZaQnQ0AWfaLRWDwmvI4/M+ IiiakccPhtFFTSRt7Mg0QU05Tb5H0TlU5qM1DYrf9vsgWnMD7LldhPRQdTfXQOwY4AMg /mrFhTTTMVrEAmLnsJqTdEjqc2bsJ7XkwwI3+fMvjXMduPTrbL74Vb2saepkitYXvTvX Q9X9+rAj0Snd8KAlZEg+O/nGNKTggSSgc2ggA7glTpVB668fTpaDqkF24MiDGcyB7BRr OT1A== X-Gm-Message-State: AOAM530yFo7GgKg1xBQxcwwTKPdWjObO7N9FHazoFllMnAZguK2BWEEW Xn7/tb/rMRb2M5lRBYIM07MyBPIvIss= X-Google-Smtp-Source: ABdhPJyqE1ohS2TSgebv7K5iabFQEl7wcTcGFvBsF7yvXcxIbElsqBcsJY3s4Q6L/Rom+/w3AzJBdg== X-Received: by 2002:a62:f248:0:b029:20a:f9d5:dac3 with SMTP id y8-20020a62f2480000b029020af9d5dac3mr2159803pfl.13.1616464432788; Mon, 22 Mar 2021 18:53:52 -0700 (PDT) Received: from fainelli-desktop.igp.broadcom.net ([192.19.223.252]) by smtp.gmail.com with ESMTPSA id 14sm3721376pfl.1.2021.03.22.18.53.51 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 22 Mar 2021 18:53:52 -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 v3] swiotlb: Make SWIOTLB_NO_FORCE perform no allocation Date: Mon, 22 Mar 2021 18:53:49 -0700 Message-Id: <20210323015350.399493-1-f.fainelli@gmail.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20210321033740.312500-1-f.fainelli@gmail.com> References: <20210321033740.312500-1-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 v3: - patch all call sites that can allocate SWIOTLB memory Changes in v2: - rebased against devel/for-linus-5.13 - updated commit message to reflect variable names kernel/dma/swiotlb.c | 18 ++++++++++++++---- 1 file changed, 14 insertions(+), 4 deletions(-) diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c index 539c76beb52e..0a5b6f7e75bc 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; } @@ -174,6 +172,9 @@ int __init swiotlb_init_with_tbl(char *tlb, unsigned long nslabs, int verbose) struct io_tlb_mem *mem; size_t alloc_size; + if (swiotlb_force == SWIOTLB_NO_FORCE) + return 0; + /* protect against double initialization */ if (WARN_ON_ONCE(io_tlb_default_mem)) return -ENOMEM; @@ -211,6 +212,9 @@ 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) @@ -240,6 +244,9 @@ swiotlb_late_init_with_default_size(size_t default_size) unsigned int order; int rc = 0; + if (swiotlb_force == SWIOTLB_NO_FORCE) + return 0; + /* * Get IO TLB memory from the low pages */ @@ -276,6 +283,9 @@ swiotlb_late_init_with_tbl(char *tlb, unsigned long nslabs) unsigned long bytes = nslabs << IO_TLB_SHIFT, i; struct io_tlb_mem *mem; + if (swiotlb_force == SWIOTLB_NO_FORCE) + return 0; + /* protect against double initialization */ if (WARN_ON_ONCE(io_tlb_default_mem)) return -ENOMEM; -- 2.25.1