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authorVojtech Pavlik <vojtech@suse.cz>2006-09-26 10:52:28 +0200
committerAndi Kleen <andi@basil.nowhere.org>2006-09-26 10:52:28 +0200
commita670fad0adb1cc6202a607d250f10bd380593905 (patch)
tree697d27fe0c92a65829f727f17f7048d46a675e4d /arch/x86_64/kernel/time.c
parent81af4449af9c9b686a4eeeb00112614621655704 (diff)
downloadop-kernel-dev-a670fad0adb1cc6202a607d250f10bd380593905.zip
op-kernel-dev-a670fad0adb1cc6202a607d250f10bd380593905.tar.gz
[PATCH] Add initalization of the RDTSCP auxilliary values
This patch adds initalization of the RDTSCP auxilliary values to CPU numbers to time.c. If RDTSCP is available, the MSRs are written with the respective values. It can be later used to initalize per-cpu timekeeping variables. AK: Some cleanups. Move externs into headers and fix CPU hotplug. Signed-off-by: Vojtech Pavlik <vojtech@suse.cz> Signed-off-by: Andi Kleen <ak@suse.de>
Diffstat (limited to 'arch/x86_64/kernel/time.c')
-rw-r--r--arch/x86_64/kernel/time.c47
1 files changed, 35 insertions, 12 deletions
diff --git a/arch/x86_64/kernel/time.c b/arch/x86_64/kernel/time.c
index 7a9b182..97b9e46d 100644
--- a/arch/x86_64/kernel/time.c
+++ b/arch/x86_64/kernel/time.c
@@ -24,6 +24,8 @@
#include <linux/device.h>
#include <linux/sysdev.h>
#include <linux/bcd.h>
+#include <linux/notifier.h>
+#include <linux/cpu.h>
#include <linux/kallsyms.h>
#include <linux/acpi.h>
#ifdef CONFIG_ACPI
@@ -49,7 +51,7 @@ static void cpufreq_delayed_get(void);
extern void i8254_timer_resume(void);
extern int using_apic_timer;
-static char *time_init_gtod(void);
+static char *timename = NULL;
DEFINE_SPINLOCK(rtc_lock);
EXPORT_SYMBOL(rtc_lock);
@@ -893,11 +895,21 @@ static struct irqaction irq0 = {
timer_interrupt, IRQF_DISABLED, CPU_MASK_NONE, "timer", NULL, NULL
};
-void __init time_init(void)
+static int __cpuinit
+time_cpu_notifier(struct notifier_block *nb, unsigned long action, void *hcpu)
{
- char *timename;
- char *gtod;
+ unsigned cpu = (unsigned long) hcpu;
+ if (action == CPU_ONLINE &&
+ cpu_has(&cpu_data[cpu], X86_FEATURE_RDTSCP)) {
+ unsigned p;
+ p = smp_processor_id() | (cpu_to_node(smp_processor_id())<<12);
+ write_rdtscp_aux(p);
+ }
+ return NOTIFY_DONE;
+}
+void __init time_init(void)
+{
if (nohpet)
vxtime.hpet_address = 0;
@@ -931,18 +943,19 @@ void __init time_init(void)
}
vxtime.mode = VXTIME_TSC;
- gtod = time_init_gtod();
-
- printk(KERN_INFO "time.c: Using %ld.%06ld MHz WALL %s GTOD %s timer.\n",
- vxtime_hz / 1000000, vxtime_hz % 1000000, timename, gtod);
- printk(KERN_INFO "time.c: Detected %d.%03d MHz processor.\n",
- cpu_khz / 1000, cpu_khz % 1000);
vxtime.quot = (USEC_PER_SEC << US_SCALE) / vxtime_hz;
vxtime.tsc_quot = (USEC_PER_MSEC << US_SCALE) / cpu_khz;
vxtime.last_tsc = get_cycles_sync();
setup_irq(0, &irq0);
set_cyc2ns_scale(cpu_khz);
+
+ hotcpu_notifier(time_cpu_notifier, 0);
+ time_cpu_notifier(NULL, CPU_ONLINE, (void *)(long)smp_processor_id());
+
+#ifndef CONFIG_SMP
+ time_init_gtod();
+#endif
}
/*
@@ -973,12 +986,13 @@ __cpuinit int unsynchronized_tsc(void)
/*
* Decide what mode gettimeofday should use.
*/
-__init static char *time_init_gtod(void)
+void time_init_gtod(void)
{
char *timetype;
if (unsynchronized_tsc())
notsc = 1;
+
if (vxtime.hpet_address && notsc) {
timetype = hpet_use_timer ? "HPET" : "PIT/HPET";
if (hpet_use_timer)
@@ -1001,7 +1015,16 @@ __init static char *time_init_gtod(void)
timetype = hpet_use_timer ? "HPET/TSC" : "PIT/TSC";
vxtime.mode = VXTIME_TSC;
}
- return timetype;
+
+ printk(KERN_INFO "time.c: Using %ld.%06ld MHz WALL %s GTOD %s timer.\n",
+ vxtime_hz / 1000000, vxtime_hz % 1000000, timename, timetype);
+ printk(KERN_INFO "time.c: Detected %d.%03d MHz processor.\n",
+ cpu_khz / 1000, cpu_khz % 1000);
+ vxtime.quot = (USEC_PER_SEC << US_SCALE) / vxtime_hz;
+ vxtime.tsc_quot = (USEC_PER_MSEC << US_SCALE) / cpu_khz;
+ vxtime.last_tsc = get_cycles_sync();
+
+ set_cyc2ns_scale(cpu_khz);
}
__setup("report_lost_ticks", time_setup);
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