linux/arch/i386/kernel/cpu/mcheck/therm_throt.c
Dmitriy Zavin 66aea9913c [PATCH] i386: Make the jiffies compares use the 64bit safe macros.
Signed-off-by: Dmitriy Zavin <dmitriyz@google.com>
Signed-off-by: Andi Kleen <ak@suse.de>
2006-09-26 10:52:42 +02:00

60 lines
1.7 KiB
C

/*
* linux/arch/i386/kerne/cpu/mcheck/therm_throt.c
*
* Thermal throttle event support code.
*
* Author: Dmitriy Zavin (dmitriyz@google.com)
*
* Credits: Adapted from Zwane Mwaikambo's original code in mce_intel.c.
*
*/
#include <linux/percpu.h>
#include <linux/cpu.h>
#include <asm/cpu.h>
#include <linux/notifier.h>
#include <asm/therm_throt.h>
/* How long to wait between reporting thermal events */
#define CHECK_INTERVAL (300 * HZ)
static DEFINE_PER_CPU(__u64, next_check);
/***
* therm_throt_process - Process thermal throttling event
* @curr: Whether the condition is current or not (boolean), since the
* thermal interrupt normally gets called both when the thermal
* event begins and once the event has ended.
*
* This function is normally called by the thermal interrupt after the
* IRQ has been acknowledged.
*
* It will take care of rate limiting and printing messages to the syslog.
*
* Returns: 0 : Event should NOT be further logged, i.e. still in
* "timeout" from previous log message.
* 1 : Event should be logged further, and a message has been
* printed to the syslog.
*/
int therm_throt_process(int curr)
{
unsigned int cpu = smp_processor_id();
__u64 tmp_jiffs = get_jiffies_64();
if (time_before64(tmp_jiffs, __get_cpu_var(next_check)))
return 0;
__get_cpu_var(next_check) = tmp_jiffs + CHECK_INTERVAL;
/* if we just entered the thermal event */
if (curr) {
printk(KERN_CRIT "CPU%d: Temperature above threshold, "
"cpu clock throttled\n", cpu);
add_taint(TAINT_MACHINE_CHECK);
} else {
printk(KERN_CRIT "CPU%d: Temperature/speed normal\n", cpu);
}
return 1;
}