Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933102Ab3FRTkP (ORCPT ); Tue, 18 Jun 2013 15:40:15 -0400 Received: from e39.co.us.ibm.com ([32.97.110.160]:54223 "EHLO e39.co.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751301Ab3FRTkN (ORCPT ); Tue, 18 Jun 2013 15:40:13 -0400 Date: Tue, 18 Jun 2013 14:38:26 -0500 From: "Philip J. Kelleher" To: axboe@kernel.dk Cc: linux-kernel@vger.kernel.org, brking@linux.vnet.ibm.com Subject: [PATCH 3/11] rsxx: Fixes soft-lockup issues during DMAs. Message-ID: <20130618193826.GD6492@oc6784271780.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.5.20 (2009-12-10) X-TM-AS-MML: No X-Content-Scanned: Fidelis XPS MAILER x-cbid: 13061819-3620-0000-0000-0000032D83EA Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3720 Lines: 113 From: Philip J Kelleher The workqueue mechanism has been reworked to prevent soft lockup issues from occuring by adding in mutex sychronization. Signed-off-by: Philip J Kelleher ------------------------------------------------------------------------------- diff -uprN -X linux-block-vanilla/Documentation/dontdiff linux-block-vanilla/drivers/block/rsxx/dma.c linux-block/drivers/block/rsxx/dma.c --- linux-block-vanilla/drivers/block/rsxx/dma.c 2013-06-17 16:53:06.805154023 -0500 +++ linux-block/drivers/block/rsxx/dma.c 2013-06-17 16:53:37.564908059 -0500 @@ -381,15 +381,13 @@ static void dma_engine_stalled(unsigned } } -static void rsxx_issue_dmas(struct work_struct *work) +static void rsxx_issue_dmas(struct rsxx_dma_ctrl *ctrl) { - struct rsxx_dma_ctrl *ctrl; struct rsxx_dma *dma; int tag; int cmds_pending = 0; struct hw_cmd *hw_cmd_buf; - ctrl = container_of(work, struct rsxx_dma_ctrl, issue_dma_work); hw_cmd_buf = ctrl->cmd.buf; if (unlikely(ctrl->card->halt) || @@ -469,9 +467,8 @@ static void rsxx_issue_dmas(struct work_ } } -static void rsxx_dma_done(struct work_struct *work) +static void rsxx_dma_done(struct rsxx_dma_ctrl *ctrl) { - struct rsxx_dma_ctrl *ctrl; struct rsxx_dma *dma; unsigned long flags; u16 count; @@ -479,7 +476,6 @@ static void rsxx_dma_done(struct work_st u8 tag; struct hw_status *hw_st_buf; - ctrl = container_of(work, struct rsxx_dma_ctrl, dma_done_work); hw_st_buf = ctrl->status.buf; if (unlikely(ctrl->card->halt) || @@ -555,6 +551,28 @@ static void rsxx_dma_done(struct work_st spin_unlock_bh(&ctrl->queue_lock); } +static void rsxx_schedule_issue(struct work_struct *work) +{ + struct rsxx_dma_ctrl *ctrl; + + ctrl = container_of(work, struct rsxx_dma_ctrl, issue_dma_work); + + mutex_lock(&ctrl->work_lock); + rsxx_issue_dmas(ctrl); + mutex_unlock(&ctrl->work_lock); +} + +static void rsxx_schedule_done(struct work_struct *work) +{ + struct rsxx_dma_ctrl *ctrl; + + ctrl = container_of(work, struct rsxx_dma_ctrl, dma_done_work); + + mutex_lock(&ctrl->work_lock); + rsxx_dma_done(ctrl); + mutex_unlock(&ctrl->work_lock); +} + static int rsxx_queue_discard(struct rsxx_cardinfo *card, struct list_head *q, unsigned int laddr, @@ -789,6 +807,7 @@ static int rsxx_dma_ctrl_init(struct pci spin_lock_init(&ctrl->trackers->lock); spin_lock_init(&ctrl->queue_lock); + mutex_init(&ctrl->work_lock); INIT_LIST_HEAD(&ctrl->queue); setup_timer(&ctrl->activity_timer, dma_engine_stalled, @@ -802,8 +821,8 @@ static int rsxx_dma_ctrl_init(struct pci if (!ctrl->done_wq) return -ENOMEM; - INIT_WORK(&ctrl->issue_dma_work, rsxx_issue_dmas); - INIT_WORK(&ctrl->dma_done_work, rsxx_dma_done); + INIT_WORK(&ctrl->issue_dma_work, rsxx_schedule_issue); + INIT_WORK(&ctrl->dma_done_work, rsxx_schedule_done); st = rsxx_hw_buffers_init(dev, ctrl); if (st) diff -uprN -X linux-block-vanilla/Documentation/dontdiff linux-block-vanilla/drivers/block/rsxx/rsxx_priv.h linux-block/drivers/block/rsxx/rsxx_priv.h --- linux-block-vanilla/drivers/block/rsxx/rsxx_priv.h 2013-06-17 16:53:06.812153024 -0500 +++ linux-block/drivers/block/rsxx/rsxx_priv.h 2013-06-17 16:53:37.572905400 -0500 @@ -115,6 +115,7 @@ struct rsxx_dma_ctrl { struct timer_list activity_timer; struct dma_tracker_list *trackers; struct rsxx_dma_stats stats; + struct mutex work_lock; }; struct rsxx_cardinfo { -- 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/