Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760765AbZCPRG4 (ORCPT ); Mon, 16 Mar 2009 13:06:56 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1760225AbZCPRGR (ORCPT ); Mon, 16 Mar 2009 13:06:17 -0400 Received: from wa4ehsobe003.messaging.microsoft.com ([216.32.181.13]:54383 "EHLO WA4EHSOBE003.bigfish.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1760280AbZCPRGO (ORCPT ); Mon, 16 Mar 2009 13:06:14 -0400 X-BigFish: VPS1(zzzz1202hzzz32i61h) X-Spam-TCS-SCL: 0:0 X-FB-SS: 5, X-WSS-ID: 0KGLZH2-02-R4W-01 From: Joerg Roedel To: Ingo Molnar CC: linux-kernel@vger.kernel.org, iommu@lists.linux-foundation.org, Joerg Roedel Subject: [PATCH 2/3] dma-debug: add a check dma memory leaks Date: Mon, 16 Mar 2009 18:05:29 +0100 Message-ID: <1237223130-26519-3-git-send-email-joerg.roedel@amd.com> X-Mailer: git-send-email 1.5.6.4 In-Reply-To: <1237223130-26519-1-git-send-email-joerg.roedel@amd.com> References: <1237223130-26519-1-git-send-email-joerg.roedel@amd.com> X-OriginalArrivalTime: 16 Mar 2009 17:05:30.0540 (UTC) FILETIME=[69480EC0:01C9A659] 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: 2832 Lines: 114 Impact: allow architectures to monitor busses for dma mem leakage This patch adds checking code to detect if a device has pending DMA operations when it is about to be unbound from its device driver. Signed-off-by: Joerg Roedel --- include/linux/dma-debug.h | 7 +++++ lib/dma-debug.c | 55 +++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 62 insertions(+), 0 deletions(-) diff --git a/include/linux/dma-debug.h b/include/linux/dma-debug.h index 46a11c1..e851d23 100644 --- a/include/linux/dma-debug.h +++ b/include/linux/dma-debug.h @@ -24,9 +24,12 @@ struct device; struct scatterlist; +struct bus_type; #ifdef CONFIG_DMA_API_DEBUG +extern void dma_debug_add_bus(struct bus_type *bus); + extern void dma_debug_init(u32 num_entries); extern void debug_dma_map_page(struct device *dev, struct page *page, @@ -80,6 +83,10 @@ extern void debug_dma_dump_mappings(struct device *dev); #else /* CONFIG_DMA_API_DEBUG */ +void dma_debug_add_bus(struct bus_type *bus) +{ +} + static inline void dma_debug_init(u32 num_entries) { } diff --git a/lib/dma-debug.c b/lib/dma-debug.c index b6a303f..3b20ae9 100644 --- a/lib/dma-debug.c +++ b/lib/dma-debug.c @@ -400,6 +400,61 @@ out_err: return -ENOMEM; } +static int device_dma_allocations(struct device *dev) +{ + struct dma_debug_entry *entry; + unsigned long flags; + int count = 0, i; + + for (i = 0; i < HASH_SIZE; ++i) { + spin_lock_irqsave(&dma_entry_hash[i].lock, flags); + list_for_each_entry(entry, &dma_entry_hash[i].list, list) { + if (entry->dev == dev) + count += 1; + } + spin_unlock_irqrestore(&dma_entry_hash[i].lock, flags); + } + + return count; +} + +static int dma_debug_device_change(struct notifier_block *nb, + unsigned long action, void *data) +{ + struct device *dev = data; + int count; + + + switch (action) { + case BUS_NOTIFY_UNBIND_DRIVER: + count = device_dma_allocations(dev); + if (count == 0) + break; + err_printk(dev, NULL, "DMA-API: device driver has pending " + "DMA allocations while released from device " + "[count=%d]\n", count); + break; + default: + break; + } + + return 0; +} + +void dma_debug_add_bus(struct bus_type *bus) +{ + struct notifier_block *nb; + + nb = kzalloc(sizeof(struct notifier_block), GFP_KERNEL); + if (nb == NULL) { + printk(KERN_ERR "dma_debug_add_bus: out of memory\n"); + return; + } + + nb->notifier_call = dma_debug_device_change; + + bus_register_notifier(bus, nb); +} /* * Let the architectures decide how many entries should be preallocated. -- 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/