From 8a98db7386b5fed82dc1df25c904b6d0ae32a2cb Mon Sep 17 00:00:00 2001 From: "Stephen M. Cameron" Date: Wed, 4 Dec 2013 17:10:07 -0600 Subject: [SCSI] hpsa: use workqueue instead of kernel thread for lockup detection Much simpler and avoids races starting/stopping the thread. Signed-off-by: Stephen M. Cameron Signed-off-by: James Bottomley --- drivers/scsi/hpsa.c | 103 +++++++++++++--------------------------------------- 1 file changed, 26 insertions(+), 77 deletions(-) (limited to 'drivers/scsi/hpsa.c') diff --git a/drivers/scsi/hpsa.c b/drivers/scsi/hpsa.c index 91e2d8398969..f929875a9187 100644 --- a/drivers/scsi/hpsa.c +++ b/drivers/scsi/hpsa.c @@ -168,10 +168,6 @@ static struct board_type products[] = { static int number_of_controllers; -static struct list_head hpsa_ctlr_list = LIST_HEAD_INIT(hpsa_ctlr_list); -static spinlock_t lockup_detector_lock; -static struct task_struct *hpsa_lockup_detector; - static irqreturn_t do_hpsa_intr_intx(int irq, void *dev_id); static irqreturn_t do_hpsa_intr_msi(int irq, void *dev_id); static int hpsa_ioctl(struct scsi_device *dev, int cmd, void *arg); @@ -4716,16 +4712,6 @@ static void hpsa_undo_allocations_after_kdump_soft_reset(struct ctlr_info *h) kfree(h); } -static void remove_ctlr_from_lockup_detector_list(struct ctlr_info *h) -{ - assert_spin_locked(&lockup_detector_lock); - if (!hpsa_lockup_detector) - return; - if (h->lockup_detected) - return; /* already stopped the lockup detector */ - list_del(&h->lockup_list); -} - /* Called when controller lockup detected. */ static void fail_all_cmds_on_list(struct ctlr_info *h, struct list_head *list) { @@ -4744,8 +4730,6 @@ static void controller_lockup_detected(struct ctlr_info *h) { unsigned long flags; - assert_spin_locked(&lockup_detector_lock); - remove_ctlr_from_lockup_detector_list(h); h->access.set_intr_mask(h, HPSA_INTR_OFF); spin_lock_irqsave(&h->lock, flags); h->lockup_detected = readl(h->vaddr + SA5_SCRATCHPAD_OFFSET); @@ -4765,7 +4749,6 @@ static void detect_controller_lockup(struct ctlr_info *h) u32 heartbeat; unsigned long flags; - assert_spin_locked(&lockup_detector_lock); now = get_jiffies_64(); /* If we've received an interrupt recently, we're ok. */ if (time_after64(h->last_intr_timestamp + @@ -4795,68 +4778,22 @@ static void detect_controller_lockup(struct ctlr_info *h) h->last_heartbeat_timestamp = now; } -static int detect_controller_lockup_thread(void *notused) -{ - struct ctlr_info *h; - unsigned long flags; - - while (1) { - struct list_head *this, *tmp; - - schedule_timeout_interruptible(HEARTBEAT_SAMPLE_INTERVAL); - if (kthread_should_stop()) - break; - spin_lock_irqsave(&lockup_detector_lock, flags); - list_for_each_safe(this, tmp, &hpsa_ctlr_list) { - h = list_entry(this, struct ctlr_info, lockup_list); - detect_controller_lockup(h); - } - spin_unlock_irqrestore(&lockup_detector_lock, flags); - } - return 0; -} - -static void add_ctlr_to_lockup_detector_list(struct ctlr_info *h) +static void hpsa_monitor_ctlr_worker(struct work_struct *work) { unsigned long flags; - - h->heartbeat_sample_interval = HEARTBEAT_SAMPLE_INTERVAL; - spin_lock_irqsave(&lockup_detector_lock, flags); - list_add_tail(&h->lockup_list, &hpsa_ctlr_list); - spin_unlock_irqrestore(&lockup_detector_lock, flags); -} - -static void start_controller_lockup_detector(struct ctlr_info *h) -{ - /* Start the lockup detector thread if not already started */ - if (!hpsa_lockup_detector) { - spin_lock_init(&lockup_detector_lock); - hpsa_lockup_detector = - kthread_run(detect_controller_lockup_thread, - NULL, HPSA); - } - if (!hpsa_lockup_detector) { - dev_warn(&h->pdev->dev, - "Could not start lockup detector thread\n"); + struct ctlr_info *h = container_of(to_delayed_work(work), + struct ctlr_info, monitor_ctlr_work); + detect_controller_lockup(h); + if (h->lockup_detected) + return; + spin_lock_irqsave(&h->lock, flags); + if (h->remove_in_progress) { + spin_unlock_irqrestore(&h->lock, flags); return; } - add_ctlr_to_lockup_detector_list(h); -} - -static void stop_controller_lockup_detector(struct ctlr_info *h) -{ - unsigned long flags; - - spin_lock_irqsave(&lockup_detector_lock, flags); - remove_ctlr_from_lockup_detector_list(h); - /* If the list of ctlr's to monitor is empty, stop the thread */ - if (list_empty(&hpsa_ctlr_list)) { - spin_unlock_irqrestore(&lockup_detector_lock, flags); - kthread_stop(hpsa_lockup_detector); - spin_lock_irqsave(&lockup_detector_lock, flags); - hpsa_lockup_detector = NULL; - } - spin_unlock_irqrestore(&lockup_detector_lock, flags); + schedule_delayed_work(&h->monitor_ctlr_work, + h->heartbeat_sample_interval); + spin_unlock_irqrestore(&h->lock, flags); } static int hpsa_init_one(struct pci_dev *pdev, const struct pci_device_id *ent) @@ -5004,7 +4941,12 @@ reinit_after_soft_reset: hpsa_hba_inquiry(h); hpsa_register_scsi(h); /* hook ourselves into SCSI subsystem */ - start_controller_lockup_detector(h); + + /* Monitor the controller for firmware lockups */ + h->heartbeat_sample_interval = HEARTBEAT_SAMPLE_INTERVAL; + INIT_DELAYED_WORK(&h->monitor_ctlr_work, hpsa_monitor_ctlr_worker); + schedule_delayed_work(&h->monitor_ctlr_work, + h->heartbeat_sample_interval); return 0; clean4: @@ -5079,13 +5021,20 @@ static void hpsa_free_device_info(struct ctlr_info *h) static void hpsa_remove_one(struct pci_dev *pdev) { struct ctlr_info *h; + unsigned long flags; if (pci_get_drvdata(pdev) == NULL) { dev_err(&pdev->dev, "unable to remove device\n"); return; } h = pci_get_drvdata(pdev); - stop_controller_lockup_detector(h); + + /* Get rid of any controller monitoring work items */ + spin_lock_irqsave(&h->lock, flags); + h->remove_in_progress = 1; + cancel_delayed_work(&h->monitor_ctlr_work); + spin_unlock_irqrestore(&h->lock, flags); + hpsa_unregister_scsi(h); /* unhook from SCSI subsystem */ hpsa_shutdown(pdev); iounmap(h->vaddr); -- cgit v1.2.3-59-g8ed1b