Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751608AbdGZFiN (ORCPT ); Wed, 26 Jul 2017 01:38:13 -0400 Received: from mail-wm0-f49.google.com ([74.125.82.49]:32998 "EHLO mail-wm0-f49.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751579AbdGZFiK (ORCPT ); Wed, 26 Jul 2017 01:38:10 -0400 From: Anup Patel To: Rob Herring , Mark Rutland , Vinod Koul , Dan Williams Cc: Florian Fainelli , Scott Branden , Ray Jui , linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, devicetree@vger.kernel.org, dmaengine@vger.kernel.org, bcm-kernel-feedback-list@broadcom.com, Anup Patel Subject: [PATCH 5/6] dma: bcm-sba-raid: Add debugfs support Date: Wed, 26 Jul 2017 11:06:43 +0530 Message-Id: <1501047404-14456-6-git-send-email-anup.patel@broadcom.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1501047404-14456-1-git-send-email-anup.patel@broadcom.com> References: <1501047404-14456-1-git-send-email-anup.patel@broadcom.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4503 Lines: 150 This patch adds debugfs support to report stats via debugfs which in-turn will help debug hang situations. Signed-off-by: Anup Patel Reviewed-by: Ray Jui Reviewed-by: Scott Branden --- drivers/dma/bcm-sba-raid.c | 82 +++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 81 insertions(+), 1 deletion(-) diff --git a/drivers/dma/bcm-sba-raid.c b/drivers/dma/bcm-sba-raid.c index b92c756..dd1e89e 100644 --- a/drivers/dma/bcm-sba-raid.c +++ b/drivers/dma/bcm-sba-raid.c @@ -36,6 +36,7 @@ */ #include +#include #include #include #include @@ -161,6 +162,9 @@ struct sba_device { struct list_head reqs_completed_list; struct list_head reqs_aborted_list; struct list_head reqs_free_list; + /* DebugFS directory entries */ + struct dentry *root; + struct dentry *stats; }; /* ====== Command helper routines ===== */ @@ -485,6 +489,45 @@ static void sba_process_received_request(struct sba_device *sba, } } +static void sba_write_stats_in_seqfile(struct sba_device *sba, + struct seq_file *file) +{ + unsigned long flags; + struct sba_request *req; + u32 free_count = 0, alloced_count = 0, pending_count = 0; + u32 active_count = 0, aborted_count = 0, completed_count = 0; + + spin_lock_irqsave(&sba->reqs_lock, flags); + + list_for_each_entry(req, &sba->reqs_free_list, node) + free_count++; + + list_for_each_entry(req, &sba->reqs_alloc_list, node) + alloced_count++; + + list_for_each_entry(req, &sba->reqs_pending_list, node) + pending_count++; + + list_for_each_entry(req, &sba->reqs_active_list, node) + active_count++; + + list_for_each_entry(req, &sba->reqs_aborted_list, node) + aborted_count++; + + list_for_each_entry(req, &sba->reqs_completed_list, node) + completed_count++; + + spin_unlock_irqrestore(&sba->reqs_lock, flags); + + seq_printf(file, "maximum requests = %d\n", sba->max_req); + seq_printf(file, "free requests = %d\n", free_count); + seq_printf(file, "alloced requests = %d\n", alloced_count); + seq_printf(file, "pending requests = %d\n", pending_count); + seq_printf(file, "active requests = %d\n", active_count); + seq_printf(file, "aborted requests = %d\n", aborted_count); + seq_printf(file, "completed requests = %d\n", completed_count); +} + /* ====== DMAENGINE callbacks ===== */ static void sba_free_chan_resources(struct dma_chan *dchan) @@ -1450,6 +1493,19 @@ static void sba_receive_message(struct mbox_client *cl, void *msg) sba_process_received_request(sba, req); } +/* ====== Debugfs callbacks ====== */ + +static int sba_debugfs_stats_show(struct seq_file *file, void *offset) +{ + struct platform_device *pdev = to_platform_device(file->private); + struct sba_device *sba = platform_get_drvdata(pdev); + + /* Write stats in file */ + sba_write_stats_in_seqfile(sba, file); + + return 0; +} + /* ====== Platform driver routines ===== */ static int sba_prealloc_channel_resources(struct sba_device *sba) @@ -1721,10 +1777,30 @@ static int sba_probe(struct platform_device *pdev) if (ret) goto fail_free_mchans; + /* Check availability of debugfs */ + if (!debugfs_initialized()) + goto skip_debugfs; + + /* Create debugfs root entry */ + sba->root = debugfs_create_dir(dev_name(sba->dev), NULL); + if (IS_ERR_OR_NULL(sba->root)) { + ret = PTR_ERR_OR_ZERO(sba->root); + goto fail_free_resources; + } + + /* Create debugfs stats entry */ + sba->stats = debugfs_create_devm_seqfile(sba->dev, "stats", sba->root, + sba_debugfs_stats_show); + if (IS_ERR_OR_NULL(sba->stats)) { + ret = PTR_ERR_OR_ZERO(sba->stats); + goto fail_free_debugfs_root; + } +skip_debugfs: + /* Register DMA device with linux async framework */ ret = sba_async_register(sba); if (ret) - goto fail_free_resources; + goto fail_free_debugfs_root; /* Print device info */ dev_info(sba->dev, "%s using SBAv%d and %d mailbox channels", @@ -1733,6 +1809,8 @@ static int sba_probe(struct platform_device *pdev) return 0; +fail_free_debugfs_root: + debugfs_remove_recursive(sba->root); fail_free_resources: sba_freeup_channel_resources(sba); fail_free_mchans: @@ -1748,6 +1826,8 @@ static int sba_remove(struct platform_device *pdev) dma_async_device_unregister(&sba->dma_dev); + debugfs_remove_recursive(sba->root); + sba_freeup_channel_resources(sba); for (i = 0; i < sba->mchans_count; i++) -- 2.7.4