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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
parent81af4449af9c9b686a4eeeb00112614621655704 (diff)
downloadblackbird-op-linux-a670fad0adb1cc6202a607d250f10bd380593905.tar.gz
blackbird-op-linux-a670fad0adb1cc6202a607d250f10bd380593905.zip
[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')
-rw-r--r--arch/x86_64/kernel/smpboot.c2
-rw-r--r--arch/x86_64/kernel/time.c47
2 files changed, 37 insertions, 12 deletions
diff --git a/arch/x86_64/kernel/smpboot.c b/arch/x86_64/kernel/smpboot.c
index 15555879ce95..582896f7d420 100644
--- a/arch/x86_64/kernel/smpboot.c
+++ b/arch/x86_64/kernel/smpboot.c
@@ -1181,6 +1181,8 @@ void __init smp_cpus_done(unsigned int max_cpus)
#endif
check_nmi_watchdog();
+
+ time_init_gtod();
}
#ifdef CONFIG_HOTPLUG_CPU
diff --git a/arch/x86_64/kernel/time.c b/arch/x86_64/kernel/time.c
index 7a9b18224182..97b9e46d1992 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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