Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756311AbZASOsY (ORCPT ); Mon, 19 Jan 2009 09:48:24 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752022AbZASOrS (ORCPT ); Mon, 19 Jan 2009 09:47:18 -0500 Received: from outbound-wa4.frontbridge.com ([216.32.181.16]:38662 "EHLO WA4EHSOBE005.bigfish.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751615AbZASOrR (ORCPT ); Mon, 19 Jan 2009 09:47:17 -0500 X-BigFish: VPS3(zzzzzzz32i43j65h) X-Spam-TCS-SCL: 4:0 X-FB-SS: 5, X-WSS-ID: 0KDQ3QE-04-LPU-01 From: Joerg Roedel To: mingo@redhat.com, linux-kernel@vger.kernel.org CC: fujita.tomonori@lab.ntt.co.jp, dwmw2@infradead.org, iommu@lists.linux-foundation.org, Joerg Roedel Subject: [PATCH 06/16] dma-debug: add kernel command line parameters Date: Mon, 19 Jan 2009 15:46:53 +0100 Message-ID: <1232376423-11067-7-git-send-email-joerg.roedel@amd.com> X-Mailer: git-send-email 1.5.6.4 In-Reply-To: <1232376423-11067-1-git-send-email-joerg.roedel@amd.com> References: <1232376423-11067-1-git-send-email-joerg.roedel@amd.com> X-OriginalArrivalTime: 19 Jan 2009 14:47:03.0876 (UTC) FILETIME=[CAFDB840:01C97A44] MIME-Version: 1.0 Content-Type: text/plain Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2801 Lines: 98 Impact: add dma_debug= and dma_debug_entries= kernel parameters Signed-off-by: Joerg Roedel --- Documentation/kernel-parameters.txt | 10 +++++++++ lib/dma-debug.c | 38 +++++++++++++++++++++++++++++++++++ 2 files changed, 48 insertions(+), 0 deletions(-) diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 8511d35..fef67ed 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -491,6 +491,16 @@ and is between 256 and 4096 characters. It is defined in the file Range: 0 - 8192 Default: 64 + dma_debug=off If the kernel is compiled with DMA_API_DEBUG support + this option disables the debugging code at boot. + + dma_debug_entries= + This option allows to tune the number of preallocated + entries for DMA-API debugging code. One entry is + required per DMA-API allocation. Use this if the + DMA-API debugging code disables itself because the + architectural default is too low. + hpet= [X86-32,HPET] option to control HPET usage Format: { enable (default) | disable | force } disable: disable HPET and use PIT instead diff --git a/lib/dma-debug.c b/lib/dma-debug.c index d46c76e..66ed8b1 100644 --- a/lib/dma-debug.c +++ b/lib/dma-debug.c @@ -62,6 +62,9 @@ static bool global_disable __read_mostly; static u32 num_free_entries; static u32 min_free_entries; +/* number of preallocated entries requested by kernel cmdline */ +static u32 req_entries; + /* * Hash related functions * @@ -251,6 +254,9 @@ void dma_debug_init(u32 num_entries) dma_entry_hash[i].lock = SPIN_LOCK_UNLOCKED; } + if (req_entries) + num_entries = req_entries; + if (prealloc_memory(num_entries) != 0) { printk(KERN_ERR "DMA-API: debugging out of memory error " "- disabled\n"); @@ -262,3 +268,35 @@ void dma_debug_init(u32 num_entries) printk(KERN_INFO "DMA-API: debugging enabled by kernel config\n"); } +static __init int dma_debug_cmdline(char *str) +{ + if (!str) + return -EINVAL; + + if (strncmp(str, "off", 3) == 0) { + printk(KERN_INFO "DMA-API: debugging disabled on kernel " + "command line\n"); + global_disable = true; + } + + return 0; +} + +static __init int dma_debug_entries_cmdline(char *str) +{ + int res; + + if (!str) + return -EINVAL; + + res = get_option(&str, &req_entries); + + if (!res) + req_entries = 0; + + return 0; +} + +__setup("dma_debug=", dma_debug_cmdline); +__setup("dma_debug_entries=", dma_debug_entries_cmdline); + -- 1.5.6.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/