From 2d6f0d0cd94f9b8b24102300d8dd9cbbd1688826 Mon Sep 17 00:00:00 2001 From: James Bottomley Date: Sun, 4 May 2008 22:34:49 -0500 Subject: [PATCH] [SCSI] gdth: fix timer handling The global timer handling is problematic in that if someone unbinds a PCI gdth instance, the BUG_ON() in the timer will cause a panic. Fix this by making the timer start and stop depending on whether there are instances present. This should also permit binding and unbinding to work. Signed-off-by: James Bottomley --- drivers/scsi/gdth.c | 38 ++++++++++++++++++++++++++------------ 1 file changed, 26 insertions(+), 12 deletions(-) diff --git a/drivers/scsi/gdth.c b/drivers/scsi/gdth.c index 8e2e964af668..16785a2ad035 100644 --- a/drivers/scsi/gdth.c +++ b/drivers/scsi/gdth.c @@ -3724,6 +3724,8 @@ static void gdth_log_event(gdth_evt_data *dvr, char *buffer) } #ifdef GDTH_STATISTICS +static unchar gdth_timer_running; + static void gdth_timeout(ulong data) { ulong32 i; @@ -3731,7 +3733,10 @@ static void gdth_timeout(ulong data) gdth_ha_str *ha; ulong flags; - BUG_ON(list_empty(&gdth_instances)); + if(unlikely(list_empty(&gdth_instances))) { + gdth_timer_running = 0; + return; + } ha = list_first_entry(&gdth_instances, gdth_ha_str, list); spin_lock_irqsave(&ha->smp_lock, flags); @@ -3751,6 +3756,22 @@ static void gdth_timeout(ulong data) add_timer(&gdth_timer); spin_unlock_irqrestore(&ha->smp_lock, flags); } + +static void gdth_timer_init(void) +{ + if (gdth_timer_running) + return; + gdth_timer_running = 1; + TRACE2(("gdth_detect(): Initializing timer !\n")); + gdth_timer.expires = jiffies + HZ; + gdth_timer.data = 0L; + gdth_timer.function = gdth_timeout; + add_timer(&gdth_timer); +} +#else +static inline void gdth_timer_init(void) +{ +} #endif static void __init internal_setup(char *str,int *ints) @@ -4735,6 +4756,7 @@ static int __init gdth_isa_probe_one(ulong32 isa_bios) if (error) goto out_free_coal_stat; list_add_tail(&ha->list, &gdth_instances); + gdth_timer_init(); scsi_scan_host(shp); @@ -4865,6 +4887,7 @@ static int __init gdth_eisa_probe_one(ushort eisa_slot) if (error) goto out_free_coal_stat; list_add_tail(&ha->list, &gdth_instances); + gdth_timer_init(); scsi_scan_host(shp); @@ -5011,6 +5034,7 @@ static int gdth_pci_probe_one(gdth_pci_str *pcistr, list_add_tail(&ha->list, &gdth_instances); pci_set_drvdata(ha->pdev, ha); + gdth_timer_init(); scsi_scan_host(shp); @@ -5110,6 +5134,7 @@ static int __init gdth_init(void) /* initializations */ gdth_polling = TRUE; gdth_clear_events(); + init_timer(&gdth_timer); /* As default we do not probe for EISA or ISA controllers */ if (probe_eisa_isa) { @@ -5138,17 +5163,6 @@ static int __init gdth_init(void) TRACE2(("gdth_detect() %d controller detected\n", gdth_ctr_count)); - if (list_empty(&gdth_instances)) - return -ENODEV; - -#ifdef GDTH_STATISTICS - TRACE2(("gdth_detect(): Initializing timer !\n")); - init_timer(&gdth_timer); - gdth_timer.expires = jiffies + HZ; - gdth_timer.data = 0L; - gdth_timer.function = gdth_timeout; - add_timer(&gdth_timer); -#endif major = register_chrdev(0,"gdth", &gdth_fops); register_reboot_notifier(&gdth_notifier); gdth_polling = FALSE;