From mboxrd@z Thu Jan 1 00:00:00 1970 From: James Bottomley Subject: [PATCH 1/2] gdth: fix timer handling Date: Sun, 04 May 2008 22:34:49 -0500 Message-ID: <1209958489.16283.39.camel@localhost.localdomain> Mime-Version: 1.0 Content-Type: text/plain Content-Transfer-Encoding: 7bit Return-path: Received: from accolon.hansenpartnership.com ([76.243.235.52]:51536 "EHLO accolon.hansenpartnership.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752488AbYEEDew (ORCPT ); Sun, 4 May 2008 23:34:52 -0400 Received: from localhost (localhost [127.0.0.1]) by accolon.hansenpartnership.com (Postfix) with ESMTP id 5B9A5A252 for ; Sun, 4 May 2008 22:34:51 -0500 (CDT) Received: from accolon.hansenpartnership.com ([127.0.0.1]) by localhost (redscar.int.hansenpartnership.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id TfrnJqtBhGDE for ; Sun, 4 May 2008 22:34:50 -0500 (CDT) Received: from [153.66.150.222] (mulgrave-w.int.hansenpartnership.com [153.66.150.222]) by accolon.hansenpartnership.com (Postfix) with ESMTP id 35A64842B for ; Sun, 4 May 2008 22:34:50 -0500 (CDT) Sender: linux-scsi-owner@vger.kernel.org List-Id: linux-scsi@vger.kernel.org To: linux-scsi 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 files changed, 26 insertions(+), 12 deletions(-) diff --git a/drivers/scsi/gdth.c b/drivers/scsi/gdth.c index 8e2e964..16785a2 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; -- 1.5.4.4