From mboxrd@z Thu Jan 1 00:00:00 1970 From: Don Brace Subject: [PATCH V2 2/3] hpsa: limit outstanding rescans Date: Fri, 10 Mar 2017 13:58:29 -0600 Message-ID: <148917590969.14403.5657395860238305771.stgit@brunhilda> References: <148917585522.14403.4296147490747258879.stgit@brunhilda> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Return-path: Received: from mail-by2nam03on0072.outbound.protection.outlook.com ([104.47.42.72]:62202 "EHLO NAM03-BY2-obe.outbound.protection.outlook.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S932994AbdCJT6e (ORCPT ); Fri, 10 Mar 2017 14:58:34 -0500 In-Reply-To: <148917585522.14403.4296147490747258879.stgit@brunhilda> Sender: linux-scsi-owner@vger.kernel.org List-Id: linux-scsi@vger.kernel.org To: joseph.szczypek@hpe.com, gerry.morong@microsemi.com, john.hall@microsemi.com, jejb@linux.vnet.ibm.com, Kevin.Barnett@microsemi.com, Mahesh.Rajashekhara@microsemi.com, bader.alisaleh@microsemi.com, hch@infradead.org, scott.teel@microsemi.com, Viswas.G@microsemi.com, Justin.Lindley@microsemi.com, scott.benesh@microsemi.com, POSWALD@suse.com Cc: linux-scsi@vger.kernel.org avoid rescan storms. No need to queue another if one is pending. Reviewed-by: Scott Benesh Reviewed-by: Scott Teel Reviewed-by: Tomas Henzl review Signed-off-by: Don Brace --- drivers/scsi/hpsa.c | 16 +++++++++++++++- drivers/scsi/hpsa.h | 1 + 2 files changed, 16 insertions(+), 1 deletion(-) diff --git a/drivers/scsi/hpsa.c b/drivers/scsi/hpsa.c index 90b76c4..e4f57b8 100644 --- a/drivers/scsi/hpsa.c +++ b/drivers/scsi/hpsa.c @@ -5555,7 +5555,7 @@ static void hpsa_scan_complete(struct ctlr_info *h) 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); } @@ -5573,11 +5573,23 @@ static void hpsa_scan_start(struct Scsi_Host *sh) if (unlikely(lockup_detected(h))) return hpsa_scan_complete(h); + /* + * If a scan is alreay 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 @@ -5587,6 +5599,7 @@ static void hpsa_scan_start(struct Scsi_Host *sh) */ } 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))) @@ -8789,6 +8802,7 @@ static int hpsa_init_one(struct pci_dev *pdev, const struct pci_device_id *ent) 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; diff --git a/drivers/scsi/hpsa.h b/drivers/scsi/hpsa.h index bf6cdc1..6f04f2a 100644 --- a/drivers/scsi/hpsa.h +++ b/drivers/scsi/hpsa.h @@ -201,6 +201,7 @@ 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;