From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Stephen M. Cameron" Subject: [PATCH 11/19] hpsa: use per-cpu variable for lockup_detected Date: Thu, 08 May 2014 14:28:19 -0500 Message-ID: <20140508192819.13481.47987.stgit@beardog.cce.hp.com> References: <20140508192239.13481.81880.stgit@beardog.cce.hp.com> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Return-path: Received: from g2t1383g.austin.hp.com ([15.217.136.92]:25251 "EHLO g2t1383g.austin.hp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755350AbaEHT3V (ORCPT ); Thu, 8 May 2014 15:29:21 -0400 Received: from g2t2354.austin.hp.com (g2t2354.austin.hp.com [15.217.128.53]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by g2t1383g.austin.hp.com (Postfix) with ESMTPS id 1D3A1288C for ; Thu, 8 May 2014 19:10:08 +0000 (UTC) In-Reply-To: <20140508192239.13481.81880.stgit@beardog.cce.hp.com> Sender: linux-scsi-owner@vger.kernel.org List-Id: linux-scsi@vger.kernel.org To: james.bottomley@hansenpartnership.com Cc: justin.lindley@hp.com, martin.petersen@oracle.com, linux-scsi@vger.kernel.org, stephenmcameron@gmail.com, joseph.t.handzik@hp.com, thenzl@redhat.com, michael.miller@canonical.com, elliott@hp.com, scott.teel@hp.com From: Stephen M. Cameron Avoid excessive locking by using per-cpu variable for lockup_detected Signed-off-by: Stephen M. Cameron --- drivers/scsi/hpsa.c | 80 ++++++++++++++++++++++++++++++++++----------------- drivers/scsi/hpsa.h | 2 + 2 files changed, 54 insertions(+), 28 deletions(-) diff --git a/drivers/scsi/hpsa.c b/drivers/scsi/hpsa.c index e8090e2..acb88e5 100644 --- a/drivers/scsi/hpsa.c +++ b/drivers/scsi/hpsa.c @@ -48,6 +48,7 @@ #include #include #include +#include #include #include "hpsa_cmd.h" #include "hpsa.h" @@ -1991,20 +1992,26 @@ static inline void hpsa_scsi_do_simple_cmd_core(struct ctlr_info *h, wait_for_completion(&wait); } +static u32 lockup_detected(struct ctlr_info *h) +{ + int cpu; + u32 rc, *lockup_detected; + + cpu = get_cpu(); + lockup_detected = per_cpu_ptr(h->lockup_detected, cpu); + rc = *lockup_detected; + put_cpu(); + return rc; +} + static void hpsa_scsi_do_simple_cmd_core_if_no_lockup(struct ctlr_info *h, struct CommandList *c) { - unsigned long flags; - /* If controller lockup detected, fake a hardware error. */ - spin_lock_irqsave(&h->lock, flags); - if (unlikely(h->lockup_detected)) { - spin_unlock_irqrestore(&h->lock, flags); + if (unlikely(lockup_detected(h))) c->err_info->CommandStatus = CMD_HARDWARE_ERR; - } else { - spin_unlock_irqrestore(&h->lock, flags); + else hpsa_scsi_do_simple_cmd_core(h, c); - } } #define MAX_DRIVER_CMD_RETRIES 25 @@ -3964,7 +3971,6 @@ static int hpsa_scsi_queue_command_lck(struct scsi_cmnd *cmd, struct hpsa_scsi_dev_t *dev; unsigned char scsi3addr[8]; struct CommandList *c; - unsigned long flags; int rc = 0; /* Get the ptr to our adapter structure out of cmd->host. */ @@ -3977,14 +3983,11 @@ static int hpsa_scsi_queue_command_lck(struct scsi_cmnd *cmd, } memcpy(scsi3addr, dev->scsi3addr, sizeof(scsi3addr)); - spin_lock_irqsave(&h->lock, flags); - if (unlikely(h->lockup_detected)) { - spin_unlock_irqrestore(&h->lock, flags); + if (unlikely(lockup_detected(h))) { cmd->result = DID_ERROR << 16; done(cmd); return 0; } - spin_unlock_irqrestore(&h->lock, flags); c = cmd_alloc(h); if (c == NULL) { /* trouble... */ dev_err(&h->pdev->dev, "cmd_alloc returned NULL!\n"); @@ -4096,16 +4099,13 @@ static int do_not_scan_if_controller_locked_up(struct ctlr_info *h) * we can prevent new rescan threads from piling up on a * locked up controller. */ - spin_lock_irqsave(&h->lock, flags); - if (unlikely(h->lockup_detected)) { - spin_unlock_irqrestore(&h->lock, flags); + if (unlikely(lockup_detected(h))) { spin_lock_irqsave(&h->scan_lock, flags); h->scan_finished = 1; wake_up_all(&h->scan_wait_queue); spin_unlock_irqrestore(&h->scan_lock, flags); return 1; } - spin_unlock_irqrestore(&h->lock, flags); return 0; } @@ -6761,16 +6761,38 @@ static void fail_all_cmds_on_list(struct ctlr_info *h, struct list_head *list) } } +static void set_lockup_detected_for_all_cpus(struct ctlr_info *h, u32 value) +{ + int i, cpu; + + cpu = cpumask_first(cpu_online_mask); + for (i = 0; i < num_online_cpus(); i++) { + u32 *lockup_detected; + lockup_detected = per_cpu_ptr(h->lockup_detected, cpu); + *lockup_detected = value; + cpu = cpumask_next(cpu, cpu_online_mask); + } + wmb(); /* be sure the per-cpu variables are out to memory */ +} + static void controller_lockup_detected(struct ctlr_info *h) { unsigned long flags; + u32 lockup_detected; h->access.set_intr_mask(h, HPSA_INTR_OFF); spin_lock_irqsave(&h->lock, flags); - h->lockup_detected = readl(h->vaddr + SA5_SCRATCHPAD_OFFSET); + lockup_detected = readl(h->vaddr + SA5_SCRATCHPAD_OFFSET); + if (!lockup_detected) { + /* no heartbeat, but controller gave us a zero. */ + dev_warn(&h->pdev->dev, + "lockup detected but scratchpad register is zero\n"); + lockup_detected = 0xffffffff; + } + set_lockup_detected_for_all_cpus(h, lockup_detected); spin_unlock_irqrestore(&h->lock, flags); dev_warn(&h->pdev->dev, "Controller lockup detected: 0x%08x\n", - h->lockup_detected); + lockup_detected); pci_disable_device(h->pdev); spin_lock_irqsave(&h->lock, flags); fail_all_cmds_on_list(h, &h->cmpQ); @@ -6905,7 +6927,7 @@ static void hpsa_monitor_ctlr_worker(struct work_struct *work) struct ctlr_info *h = container_of(to_delayed_work(work), struct ctlr_info, monitor_ctlr_work); detect_controller_lockup(h); - if (h->lockup_detected) + if (lockup_detected(h)) return; if (hpsa_ctlr_needs_rescan(h) || hpsa_offline_devices_ready(h)) { @@ -6969,6 +6991,13 @@ reinit_after_soft_reset: spin_lock_init(&h->offline_device_lock); spin_lock_init(&h->scan_lock); spin_lock_init(&h->passthru_count_lock); + + /* Allocate and clear per-cpu variable lockup_detected */ + h->lockup_detected = alloc_percpu(u32); + if (!h->lockup_detected) + goto clean1; + set_lockup_detected_for_all_cpus(h, 0); + rc = hpsa_pci_init(h); if (rc != 0) goto clean1; @@ -7092,6 +7121,8 @@ clean4: free_irqs(h); clean2: clean1: + if (h->lockup_detected) + free_percpu(h->lockup_detected); kfree(h); return rc; } @@ -7100,16 +7131,10 @@ static void hpsa_flush_cache(struct ctlr_info *h) { char *flush_buf; struct CommandList *c; - unsigned long flags; /* Don't bother trying to flush the cache if locked up */ - spin_lock_irqsave(&h->lock, flags); - if (unlikely(h->lockup_detected)) { - spin_unlock_irqrestore(&h->lock, flags); + if (unlikely(lockup_detected(h))) return; - } - spin_unlock_irqrestore(&h->lock, flags); - flush_buf = kzalloc(4, GFP_KERNEL); if (!flush_buf) return; @@ -7193,6 +7218,7 @@ static void hpsa_remove_one(struct pci_dev *pdev) kfree(h->hba_inquiry_data); pci_disable_device(pdev); pci_release_regions(pdev); + free_percpu(h->lockup_detected); kfree(h); } diff --git a/drivers/scsi/hpsa.h b/drivers/scsi/hpsa.h index fa63576..8e8310e 100644 --- a/drivers/scsi/hpsa.h +++ b/drivers/scsi/hpsa.h @@ -191,7 +191,7 @@ struct ctlr_info { u64 last_heartbeat_timestamp; u32 heartbeat_sample_interval; atomic_t firmware_flash_in_progress; - u32 lockup_detected; + u32 *lockup_detected; struct delayed_work monitor_ctlr_work; int remove_in_progress; u32 fifo_recently_full;