ext4: ignore errors when issuing discards

[pandora-kernel.git] / kernel / watchdog.c

diff --git a/kernel/watchdog.c b/kernel/watchdog.c
index d7ebdf4..140dce7 100644 (file)
--- a/kernel/watchdog.c
+++ b/kernel/watchdog.c
@@ -27,7 +27,7 @@
 #include <asm/irq_regs.h>
 #include <linux/perf_event.h>
 
-int watchdog_enabled;
+int watchdog_enabled = 1;
 int __read_mostly softlockup_thresh = 60;
 
 static DEFINE_PER_CPU(unsigned long, watchdog_touch_ts);
@@ -43,22 +43,22 @@ static DEFINE_PER_CPU(unsigned long, hrtimer_interrupts_saved);
 static DEFINE_PER_CPU(struct perf_event *, watchdog_ev);
 #endif
 
-static int no_watchdog;
-
-
 /* boot commands */
 /*
  * Should we panic when a soft-lockup or hard-lockup occurs:
  */
 #ifdef CONFIG_HARDLOCKUP_DETECTOR
-static int hardlockup_panic;
+static int hardlockup_panic =
+                       CONFIG_BOOTPARAM_HARDLOCKUP_PANIC_VALUE;
 
 static int __init hardlockup_panic_setup(char *str)
 {
        if (!strncmp(str, "panic", 5))
                hardlockup_panic = 1;
+       else if (!strncmp(str, "nopanic", 7))
+               hardlockup_panic = 0;
        else if (!strncmp(str, "0", 1))
-               no_watchdog = 1;
+               watchdog_enabled = 0;
        return 1;
 }
 __setup("nmi_watchdog=", hardlockup_panic_setup);
@@ -77,7 +77,7 @@ __setup("softlockup_panic=", softlockup_panic_setup);
 
 static int __init nowatchdog_setup(char *str)
 {
-       no_watchdog = 1;
+       watchdog_enabled = 0;
        return 1;
 }
 __setup("nowatchdog", nowatchdog_setup);
@@ -85,7 +85,7 @@ __setup("nowatchdog", nowatchdog_setup);
 /* deprecated */
 static int __init nosoftlockup_setup(char *str)
 {
-       no_watchdog = 1;
+       watchdog_enabled = 0;
        return 1;
 }
 __setup("nosoftlockup", nosoftlockup_setup);
@@ -366,8 +366,14 @@ static int watchdog_nmi_enable(int cpu)
                goto out_save;
        }
 
-       printk(KERN_ERR "NMI watchdog disabled for cpu%i: unable to create perf event: %ld\n",
-              cpu, PTR_ERR(event));
+
+       /* vary the KERN level based on the returned errno */
+       if (PTR_ERR(event) == -EOPNOTSUPP)
+               printk(KERN_INFO "NMI watchdog disabled (cpu%i): not supported (no LAPIC?)\n", cpu);
+       else if (PTR_ERR(event) == -ENOENT)
+               printk(KERN_WARNING "NMI watchdog disabled (cpu%i): hardware events not enabled\n", cpu);
+       else
+               printk(KERN_ERR "NMI watchdog disabled (cpu%i): unable to create perf event: %ld\n", cpu, PTR_ERR(event));
        return PTR_ERR(event);
 
        /* success path */
@@ -412,19 +418,22 @@ static int watchdog_prepare_cpu(int cpu)
 static int watchdog_enable(int cpu)
 {
        struct task_struct *p = per_cpu(softlockup_watchdog, cpu);
-       int err;
+       int err = 0;
 
        /* enable the perf event */
        err = watchdog_nmi_enable(cpu);
-       if (err)
-               return err;
+
+       /* Regardless of err above, fall through and start softlockup */
 
        /* create the watchdog thread */
        if (!p) {
                p = kthread_create(watchdog, (void *)(unsigned long)cpu, "watchdog/%d", cpu);
                if (IS_ERR(p)) {
                        printk(KERN_ERR "softlockup watchdog for %i failed\n", cpu);
-                       return PTR_ERR(p);
+                       if (!err)
+                               /* if hardlockup hasn't already set this */
+                               err = PTR_ERR(p);
+                       goto out;
                }
                kthread_bind(p, cpu);
                per_cpu(watchdog_touch_ts, cpu) = 0;
@@ -432,10 +441,8 @@ static int watchdog_enable(int cpu)
                wake_up_process(p);
        }
 
-       /* if any cpu succeeds, watchdog is considered enabled for the system */
-       watchdog_enabled = 1;
-
-       return 0;
+out:
+       return err;
 }
 
 static void watchdog_disable(int cpu)
@@ -462,12 +469,16 @@ static void watchdog_disable(int cpu)
 static void watchdog_enable_all_cpus(void)
 {
        int cpu;
-       int result = 0;
+
+       watchdog_enabled = 0;
 
        for_each_online_cpu(cpu)
-               result += watchdog_enable(cpu);
+               if (!watchdog_enable(cpu))
+                       /* if any cpu succeeds, watchdog is considered
+                          enabled for the system */
+                       watchdog_enabled = 1;
 
-       if (result)
+       if (!watchdog_enabled)
                printk(KERN_ERR "watchdog: failed to be enabled on some cpus\n");
 
 }
@@ -476,9 +487,6 @@ static void watchdog_disable_all_cpus(void)
 {
        int cpu;
 
-       if (no_watchdog)
-               return;
-
        for_each_online_cpu(cpu)
                watchdog_disable(cpu);
 
@@ -498,10 +506,12 @@ int proc_dowatchdog_enabled(struct ctl_table *table, int write,
 {
        proc_dointvec(table, write, buffer, length, ppos);
 
-       if (watchdog_enabled)
-               watchdog_enable_all_cpus();
-       else
-               watchdog_disable_all_cpus();
+       if (write) {
+               if (watchdog_enabled)
+                       watchdog_enable_all_cpus();
+               else
+                       watchdog_disable_all_cpus();
+       }
        return 0;
 }
 
@@ -530,7 +540,8 @@ cpu_callback(struct notifier_block *nfb, unsigned long action, void *hcpu)
                break;
        case CPU_ONLINE:
        case CPU_ONLINE_FROZEN:
-               err = watchdog_enable(hotcpu);
+               if (watchdog_enabled)
+                       err = watchdog_enable(hotcpu);
                break;
 #ifdef CONFIG_HOTPLUG_CPU
        case CPU_UP_CANCELED:
@@ -543,7 +554,13 @@ cpu_callback(struct notifier_block *nfb, unsigned long action, void *hcpu)
                break;
 #endif /* CONFIG_HOTPLUG_CPU */
        }
-       return notifier_from_errno(err);
+
+       /*
+        * hardlockup and softlockup are not important enough
+        * to block cpu bring up.  Just always succeed and
+        * rely on printk output to flag problems.
+        */
+       return NOTIFY_OK;
 }
 
 static struct notifier_block __cpuinitdata cpu_nfb = {
@@ -555,9 +572,6 @@ void __init lockup_detector_init(void)
        void *cpu = (void *)(long)smp_processor_id();
        int err;
 
-       if (no_watchdog)
-               return;
-
        err = cpu_callback(&cpu_nfb, CPU_UP_PREPARE, cpu);
        WARN_ON(notifier_to_errno(err));