From a670fad0adb1cc6202a607d250f10bd380593905 Mon Sep 17 00:00:00 2001 From: Vojtech Pavlik Date: Tue, 26 Sep 2006 10:52:28 +0200 Subject: [PATCH] [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 Signed-off-by: Andi Kleen --- arch/x86_64/kernel/smpboot.c | 2 ++ arch/x86_64/kernel/time.c | 47 +++++++++++++++++++++++++++--------- include/asm-x86_64/proto.h | 1 + 3 files changed, 38 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 #include #include +#include +#include #include #include #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); diff --git a/include/asm-x86_64/proto.h b/include/asm-x86_64/proto.h index 038fe1f47e6f..3b1c60247902 100644 --- a/include/asm-x86_64/proto.h +++ b/include/asm-x86_64/proto.h @@ -51,6 +51,7 @@ extern unsigned long long monotonic_base; extern int sysctl_vsyscall; extern int nohpet; extern unsigned long vxtime_hz; +extern void time_init_gtod(void); extern int numa_setup(char *opt); -- 2.20.1