From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933958AbdLRPyD (ORCPT ); Mon, 18 Dec 2017 10:54:03 -0500 Received: from mail.linuxfoundation.org ([140.211.169.12]:34428 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933905AbdLRPx6 (ORCPT ); Mon, 18 Dec 2017 10:53:58 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Scott Benesh , Scott Teel , Tomas Henzl , Don Brace , "Martin K. Petersen" , Sasha Levin Subject: [PATCH 4.4 041/115] scsi: hpsa: limit outstanding rescans Date: Mon, 18 Dec 2017 16:48:30 +0100 Message-Id: <20171218152855.075769019@linuxfoundation.org> X-Mailer: git-send-email 2.15.1 In-Reply-To: <20171218152851.886086917@linuxfoundation.org> References: <20171218152851.886086917@linuxfoundation.org> User-Agent: quilt/0.65 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Don Brace [ Upstream commit 87b9e6aa87d9411f1059aa245c0c79976bc557ac ] Avoid rescan storms. No need to queue another if one is pending. Reviewed-by: Scott Benesh Reviewed-by: Scott Teel Reviewed-by: Tomas Henzl Signed-off-by: Don Brace Signed-off-by: Martin K. Petersen Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- drivers/scsi/hpsa.c | 16 +++++++++++++++- drivers/scsi/hpsa.h | 1 + 2 files changed, 16 insertions(+), 1 deletion(-) --- a/drivers/scsi/hpsa.c +++ b/drivers/scsi/hpsa.c @@ -5254,7 +5254,7 @@ static void hpsa_scan_complete(struct ct spin_lock_irqsave(&h->scan_lock, flags); h->scan_finished = 1; - wake_up_all(&h->scan_wait_queue); + wake_up(&h->scan_wait_queue); spin_unlock_irqrestore(&h->scan_lock, flags); } @@ -5272,11 +5272,23 @@ static void hpsa_scan_start(struct Scsi_ if (unlikely(lockup_detected(h))) return hpsa_scan_complete(h); + /* + * If a scan is already waiting to run, no need to add another + */ + spin_lock_irqsave(&h->scan_lock, flags); + if (h->scan_waiting) { + spin_unlock_irqrestore(&h->scan_lock, flags); + return; + } + + spin_unlock_irqrestore(&h->scan_lock, flags); + /* wait until any scan already in progress is finished. */ while (1) { spin_lock_irqsave(&h->scan_lock, flags); if (h->scan_finished) break; + h->scan_waiting = 1; spin_unlock_irqrestore(&h->scan_lock, flags); wait_event(h->scan_wait_queue, h->scan_finished); /* Note: We don't need to worry about a race between this @@ -5286,6 +5298,7 @@ static void hpsa_scan_start(struct Scsi_ */ } h->scan_finished = 0; /* mark scan as in progress */ + h->scan_waiting = 0; spin_unlock_irqrestore(&h->scan_lock, flags); if (unlikely(lockup_detected(h))) @@ -8502,6 +8515,7 @@ reinit_after_soft_reset: init_waitqueue_head(&h->event_sync_wait_queue); mutex_init(&h->reset_mutex); h->scan_finished = 1; /* no scan currently in progress */ + h->scan_waiting = 0; pci_set_drvdata(pdev, h); h->ndevices = 0; --- a/drivers/scsi/hpsa.h +++ b/drivers/scsi/hpsa.h @@ -200,6 +200,7 @@ struct ctlr_info { dma_addr_t errinfo_pool_dhandle; unsigned long *cmd_pool_bits; int scan_finished; + u8 scan_waiting : 1; spinlock_t scan_lock; wait_queue_head_t scan_wait_queue;