mirror of
https://github.com/edk2-porting/linux-next.git
synced 2024-12-23 04:34:11 +08:00
7c7fcf762e
Save the current exception frame pointer in the thread_info struct rather than in a global variable as the latter makes SMP tricky, especially when preemption is also enabled. This also replaces __frame with current_frame() and rearranges header file inclusions to make it all compile. Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Akira Takeuchi <takeuchi.akr@jp.panasonic.com>
207 lines
4.8 KiB
C
207 lines
4.8 KiB
C
/* MN10300 Watchdog timer
|
|
*
|
|
* Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
|
|
* Written by David Howells (dhowells@redhat.com)
|
|
* - Derived from arch/i386/kernel/nmi.c
|
|
*
|
|
* This program is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU General Public Licence
|
|
* as published by the Free Software Foundation; either version
|
|
* 2 of the Licence, or (at your option) any later version.
|
|
*/
|
|
#include <linux/module.h>
|
|
#include <linux/sched.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/init.h>
|
|
#include <linux/delay.h>
|
|
#include <linux/interrupt.h>
|
|
#include <linux/kernel_stat.h>
|
|
#include <linux/nmi.h>
|
|
#include <asm/processor.h>
|
|
#include <asm/system.h>
|
|
#include <asm/atomic.h>
|
|
#include <asm/intctl-regs.h>
|
|
#include <asm/rtc-regs.h>
|
|
#include <asm/div64.h>
|
|
#include <asm/smp.h>
|
|
#include <asm/gdb-stub.h>
|
|
#include <proc/clock.h>
|
|
|
|
static DEFINE_SPINLOCK(watchdog_print_lock);
|
|
static unsigned int watchdog;
|
|
static unsigned int watchdog_hz = 1;
|
|
unsigned int watchdog_alert_counter[NR_CPUS];
|
|
|
|
EXPORT_SYMBOL(touch_nmi_watchdog);
|
|
|
|
/*
|
|
* the best way to detect whether a CPU has a 'hard lockup' problem
|
|
* is to check its timer makes IRQ counts. If they are not
|
|
* changing then that CPU has some problem.
|
|
*
|
|
* since NMIs dont listen to _any_ locks, we have to be extremely
|
|
* careful not to rely on unsafe variables. The printk might lock
|
|
* up though, so we have to break up any console locks first ...
|
|
* [when there will be more tty-related locks, break them up
|
|
* here too!]
|
|
*/
|
|
static unsigned int last_irq_sums[NR_CPUS];
|
|
|
|
int __init check_watchdog(void)
|
|
{
|
|
irq_cpustat_t tmp[1];
|
|
|
|
printk(KERN_INFO "Testing Watchdog... ");
|
|
|
|
memcpy(tmp, irq_stat, sizeof(tmp));
|
|
local_irq_enable();
|
|
mdelay((10 * 1000) / watchdog_hz); /* wait 10 ticks */
|
|
local_irq_disable();
|
|
|
|
if (nmi_count(0) - tmp[0].__nmi_count <= 5) {
|
|
printk(KERN_WARNING "CPU#%d: Watchdog appears to be stuck!\n",
|
|
0);
|
|
return -1;
|
|
}
|
|
|
|
printk(KERN_INFO "OK.\n");
|
|
|
|
/* now that we know it works we can reduce NMI frequency to something
|
|
* more reasonable; makes a difference in some configs
|
|
*/
|
|
watchdog_hz = 1;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int __init setup_watchdog(char *str)
|
|
{
|
|
unsigned tmp;
|
|
int opt;
|
|
u8 ctr;
|
|
|
|
get_option(&str, &opt);
|
|
if (opt != 1)
|
|
return 0;
|
|
|
|
watchdog = opt;
|
|
if (watchdog) {
|
|
set_intr_stub(EXCEP_WDT, watchdog_handler);
|
|
ctr = WDCTR_WDCK_65536th;
|
|
WDCTR = WDCTR_WDRST | ctr;
|
|
WDCTR = ctr;
|
|
tmp = WDCTR;
|
|
|
|
tmp = __muldiv64u(1 << (16 + ctr * 2), 1000000, MN10300_WDCLK);
|
|
tmp = 1000000000 / tmp;
|
|
watchdog_hz = (tmp + 500) / 1000;
|
|
}
|
|
|
|
return 1;
|
|
}
|
|
|
|
__setup("watchdog=", setup_watchdog);
|
|
|
|
void __init watchdog_go(void)
|
|
{
|
|
u8 wdt;
|
|
|
|
if (watchdog) {
|
|
printk(KERN_INFO "Watchdog: running at %uHz\n", watchdog_hz);
|
|
wdt = WDCTR & ~WDCTR_WDCNE;
|
|
WDCTR = wdt | WDCTR_WDRST;
|
|
wdt = WDCTR;
|
|
WDCTR = wdt | WDCTR_WDCNE;
|
|
wdt = WDCTR;
|
|
|
|
check_watchdog();
|
|
}
|
|
}
|
|
|
|
#ifdef CONFIG_SMP
|
|
static void watchdog_dump_register(void *dummy)
|
|
{
|
|
printk(KERN_ERR "--- Register Dump (CPU%d) ---\n", CPUID);
|
|
show_registers(current_frame());
|
|
}
|
|
#endif
|
|
|
|
asmlinkage
|
|
void watchdog_interrupt(struct pt_regs *regs, enum exception_code excep)
|
|
{
|
|
/*
|
|
* Since current-> is always on the stack, and we always switch
|
|
* the stack NMI-atomically, it's safe to use smp_processor_id().
|
|
*/
|
|
int sum, cpu;
|
|
int irq = NMIIRQ;
|
|
u8 wdt, tmp;
|
|
|
|
wdt = WDCTR & ~WDCTR_WDCNE;
|
|
WDCTR = wdt;
|
|
tmp = WDCTR;
|
|
NMICR = NMICR_WDIF;
|
|
|
|
nmi_count(smp_processor_id())++;
|
|
kstat_incr_irqs_this_cpu(irq, irq_to_desc(irq));
|
|
|
|
for_each_online_cpu(cpu) {
|
|
|
|
sum = irq_stat[cpu].__irq_count;
|
|
|
|
if ((last_irq_sums[cpu] == sum)
|
|
#if defined(CONFIG_GDBSTUB) && defined(CONFIG_SMP)
|
|
&& !(CHK_GDBSTUB_BUSY()
|
|
|| atomic_read(&cpu_doing_single_step))
|
|
#endif
|
|
) {
|
|
/*
|
|
* Ayiee, looks like this CPU is stuck ...
|
|
* wait a few IRQs (5 seconds) before doing the oops ...
|
|
*/
|
|
watchdog_alert_counter[cpu]++;
|
|
if (watchdog_alert_counter[cpu] == 5 * watchdog_hz) {
|
|
spin_lock(&watchdog_print_lock);
|
|
/*
|
|
* We are in trouble anyway, lets at least try
|
|
* to get a message out.
|
|
*/
|
|
bust_spinlocks(1);
|
|
printk(KERN_ERR
|
|
"NMI Watchdog detected LOCKUP on CPU%d,"
|
|
" pc %08lx, registers:\n",
|
|
cpu, regs->pc);
|
|
#ifdef CONFIG_SMP
|
|
printk(KERN_ERR
|
|
"--- Register Dump (CPU%d) ---\n",
|
|
CPUID);
|
|
#endif
|
|
show_registers(regs);
|
|
#ifdef CONFIG_SMP
|
|
smp_nmi_call_function(watchdog_dump_register,
|
|
NULL, 1);
|
|
#endif
|
|
printk(KERN_NOTICE "console shuts up ...\n");
|
|
console_silent();
|
|
spin_unlock(&watchdog_print_lock);
|
|
bust_spinlocks(0);
|
|
#ifdef CONFIG_GDBSTUB
|
|
if (CHK_GDBSTUB_BUSY_AND_ACTIVE())
|
|
gdbstub_exception(regs, excep);
|
|
else
|
|
gdbstub_intercept(regs, excep);
|
|
#endif
|
|
do_exit(SIGSEGV);
|
|
}
|
|
} else {
|
|
last_irq_sums[cpu] = sum;
|
|
watchdog_alert_counter[cpu] = 0;
|
|
}
|
|
}
|
|
|
|
WDCTR = wdt | WDCTR_WDRST;
|
|
tmp = WDCTR;
|
|
WDCTR = wdt | WDCTR_WDCNE;
|
|
tmp = WDCTR;
|
|
}
|