-
Notifications
You must be signed in to change notification settings - Fork 0
Commit
This commit does not belong to any branch on this repository, and may belong to a fork outside of the repository.
sparc64: Implement NMI watchdog on capable cpus.
Signed-off-by: David S. Miller <davem@davemloft.net>
- Loading branch information
David S. Miller
committed
Jan 30, 2009
1 parent
c3cf5e8
commit e5553a6
Showing
10 changed files
with
309 additions
and
163 deletions.
There are no files selected for viewing
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| Original file line number | Diff line number | Diff line change |
|---|---|---|
|
|
@@ -14,6 +14,8 @@ enum die_val { | |
| DIE_TRAP, | ||
| DIE_TRAP_TL1, | ||
| DIE_CALL, | ||
| DIE_NMI, | ||
| DIE_NMIWATCHDOG, | ||
| }; | ||
|
|
||
| #endif | ||
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| Original file line number | Diff line number | Diff line change |
|---|---|---|
| @@ -0,0 +1,10 @@ | ||
| #ifndef __NMI_H | ||
| #define __NMI_H | ||
|
|
||
| extern int __init nmi_init(void); | ||
| extern void perfctr_irq(int irq, struct pt_regs *regs); | ||
| extern void nmi_adjust_hz(unsigned int new_hz); | ||
|
|
||
| extern int nmi_usable; | ||
|
|
||
| #endif /* __NMI_H */ |
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| Original file line number | Diff line number | Diff line change |
|---|---|---|
| @@ -0,0 +1,224 @@ | ||
| /* Pseudo NMI support on sparc64 systems. | ||
| * | ||
| * Copyright (C) 2009 David S. Miller <davem@davemloft.net> | ||
| * | ||
| * The NMI watchdog support and infrastructure is based almost | ||
| * entirely upon the x86 NMI support code. | ||
| */ | ||
| #include <linux/kernel.h> | ||
| #include <linux/param.h> | ||
| #include <linux/init.h> | ||
| #include <linux/percpu.h> | ||
| #include <linux/nmi.h> | ||
| #include <linux/module.h> | ||
| #include <linux/kprobes.h> | ||
| #include <linux/kernel_stat.h> | ||
| #include <linux/slab.h> | ||
| #include <linux/kdebug.h> | ||
| #include <linux/delay.h> | ||
| #include <linux/smp.h> | ||
|
|
||
| #include <asm/ptrace.h> | ||
| #include <asm/local.h> | ||
| #include <asm/pcr.h> | ||
|
|
||
| /* We don't have a real NMI on sparc64, but we can fake one | ||
| * up using profiling counter overflow interrupts and interrupt | ||
| * levels. | ||
| * | ||
| * The profile overflow interrupts at level 15, so we use | ||
| * level 14 as our IRQ off level. | ||
| */ | ||
|
|
||
| static int nmi_watchdog_active; | ||
| static int panic_on_timeout; | ||
|
|
||
| int nmi_usable; | ||
| EXPORT_SYMBOL_GPL(nmi_usable); | ||
|
|
||
| static unsigned int nmi_hz = HZ; | ||
|
|
||
| static DEFINE_PER_CPU(unsigned int, last_irq_sum); | ||
| static DEFINE_PER_CPU(local_t, alert_counter); | ||
| static DEFINE_PER_CPU(int, nmi_touch); | ||
|
|
||
| void touch_nmi_watchdog(void) | ||
| { | ||
| if (nmi_watchdog_active) { | ||
| int cpu; | ||
|
|
||
| for_each_present_cpu(cpu) { | ||
| if (per_cpu(nmi_touch, cpu) != 1) | ||
| per_cpu(nmi_touch, cpu) = 1; | ||
| } | ||
| } | ||
|
|
||
| touch_softlockup_watchdog(); | ||
| } | ||
| EXPORT_SYMBOL(touch_nmi_watchdog); | ||
|
|
||
| static void die_nmi(const char *str, struct pt_regs *regs, int do_panic) | ||
| { | ||
| if (notify_die(DIE_NMIWATCHDOG, str, regs, 0, | ||
| pt_regs_trap_type(regs), SIGINT) == NOTIFY_STOP) | ||
| return; | ||
|
|
||
| console_verbose(); | ||
| bust_spinlocks(1); | ||
|
|
||
| printk(KERN_EMERG "%s", str); | ||
| printk(" on CPU%d, ip %08lx, registers:\n", | ||
| smp_processor_id(), regs->tpc); | ||
| show_regs(regs); | ||
|
|
||
| bust_spinlocks(0); | ||
|
|
||
| if (do_panic || panic_on_oops) | ||
| panic("Non maskable interrupt"); | ||
|
|
||
| local_irq_enable(); | ||
| do_exit(SIGBUS); | ||
| } | ||
|
|
||
| notrace __kprobes void perfctr_irq(int irq, struct pt_regs *regs) | ||
| { | ||
| unsigned int sum, touched = 0; | ||
| int cpu = smp_processor_id(); | ||
|
|
||
| clear_softint(1 << irq); | ||
| pcr_ops->write(PCR_PIC_PRIV); | ||
|
|
||
| local_cpu_data().__nmi_count++; | ||
|
|
||
| if (notify_die(DIE_NMI, "nmi", regs, 0, | ||
| pt_regs_trap_type(regs), SIGINT) == NOTIFY_STOP) | ||
| touched = 1; | ||
|
|
||
| sum = kstat_cpu(cpu).irqs[0]; | ||
| if (__get_cpu_var(nmi_touch)) { | ||
| __get_cpu_var(nmi_touch) = 0; | ||
| touched = 1; | ||
| } | ||
| if (!touched && __get_cpu_var(last_irq_sum) == sum) { | ||
| local_inc(&__get_cpu_var(alert_counter)); | ||
| if (local_read(&__get_cpu_var(alert_counter)) == 5 * nmi_hz) | ||
| die_nmi("BUG: NMI Watchdog detected LOCKUP", | ||
| regs, panic_on_timeout); | ||
| } else { | ||
| __get_cpu_var(last_irq_sum) = sum; | ||
| local_set(&__get_cpu_var(alert_counter), 0); | ||
| } | ||
| if (nmi_usable) { | ||
| write_pic(picl_value(nmi_hz)); | ||
| pcr_ops->write(pcr_enable); | ||
| } | ||
| } | ||
|
|
||
| static inline unsigned int get_nmi_count(int cpu) | ||
| { | ||
| return cpu_data(cpu).__nmi_count; | ||
| } | ||
|
|
||
| static int endflag __initdata; | ||
|
|
||
| static __init void nmi_cpu_busy(void *data) | ||
| { | ||
| local_irq_enable_in_hardirq(); | ||
| while (endflag == 0) | ||
| mb(); | ||
| } | ||
|
|
||
| static void report_broken_nmi(int cpu, int *prev_nmi_count) | ||
| { | ||
| printk(KERN_CONT "\n"); | ||
|
|
||
| printk(KERN_WARNING | ||
| "WARNING: CPU#%d: NMI appears to be stuck (%d->%d)!\n", | ||
| cpu, prev_nmi_count[cpu], get_nmi_count(cpu)); | ||
|
|
||
| printk(KERN_WARNING | ||
| "Please report this to bugzilla.kernel.org,\n"); | ||
| printk(KERN_WARNING | ||
| "and attach the output of the 'dmesg' command.\n"); | ||
|
|
||
| nmi_usable = 0; | ||
| } | ||
|
|
||
| static void stop_watchdog(void *unused) | ||
| { | ||
| pcr_ops->write(PCR_PIC_PRIV); | ||
| } | ||
|
|
||
| static int __init check_nmi_watchdog(void) | ||
| { | ||
| unsigned int *prev_nmi_count; | ||
| int cpu, err; | ||
|
|
||
| prev_nmi_count = kmalloc(nr_cpu_ids * sizeof(unsigned int), GFP_KERNEL); | ||
| if (!prev_nmi_count) { | ||
| err = -ENOMEM; | ||
| goto error; | ||
| } | ||
|
|
||
| printk(KERN_INFO "Testing NMI watchdog ... "); | ||
|
|
||
| smp_call_function(nmi_cpu_busy, (void *)&endflag, 0); | ||
|
|
||
| for_each_possible_cpu(cpu) | ||
| prev_nmi_count[cpu] = get_nmi_count(cpu); | ||
| local_irq_enable(); | ||
| mdelay((20 * 1000) / nmi_hz); /* wait 20 ticks */ | ||
|
|
||
| for_each_online_cpu(cpu) { | ||
| if (get_nmi_count(cpu) - prev_nmi_count[cpu] <= 5) | ||
| report_broken_nmi(cpu, prev_nmi_count); | ||
| } | ||
| endflag = 1; | ||
| if (!nmi_usable) { | ||
| kfree(prev_nmi_count); | ||
| err = -ENODEV; | ||
| goto error; | ||
| } | ||
| printk("OK.\n"); | ||
|
|
||
| nmi_hz = 1; | ||
|
|
||
| kfree(prev_nmi_count); | ||
| return 0; | ||
| error: | ||
| on_each_cpu(stop_watchdog, NULL, 1); | ||
| return err; | ||
| } | ||
|
|
||
| static void start_watchdog(void *unused) | ||
| { | ||
| pcr_ops->write(PCR_PIC_PRIV); | ||
| write_pic(picl_value(nmi_hz)); | ||
|
|
||
| pcr_ops->write(pcr_enable); | ||
| } | ||
|
|
||
| void nmi_adjust_hz(unsigned int new_hz) | ||
| { | ||
| nmi_hz = new_hz; | ||
| on_each_cpu(start_watchdog, NULL, 1); | ||
| } | ||
| EXPORT_SYMBOL_GPL(nmi_adjust_hz); | ||
|
|
||
| int __init nmi_init(void) | ||
| { | ||
| nmi_usable = 1; | ||
|
|
||
| on_each_cpu(start_watchdog, NULL, 1); | ||
|
|
||
| return check_nmi_watchdog(); | ||
| } | ||
|
|
||
| static int __init setup_nmi_watchdog(char *str) | ||
| { | ||
| if (!strncmp(str, "panic", 5)) | ||
| panic_on_timeout = 1; | ||
|
|
||
| return 0; | ||
| } | ||
| __setup("nmi_watchdog=", setup_nmi_watchdog); |
Oops, something went wrong.