Commit ee238e5c authored by Glauber de Oliveira Costa's avatar Glauber de Oliveira Costa Committed by Ingo Molnar
Browse files

x86: prepare time related functions for paravirt 



This patch add provisions for time related functions so they
can be later replaced by paravirt versions.

it basically encloses {g,s}et_wallclock inside the
already existent functions update_persistent_clock and
read_persistent_clock, and defines {s,g}et_wallclock
to the core of such functions.

it also allow for a later-on-game time initialization, as done
by i386. Paravirt guests can set a function to do their own
initialization this way.

Signed-off-by: default avatarGlauber de Oliveira Costa <gcosta@redhat.com>
Signed-off-by: default avatarSteven Rostedt <rostedt@goodmis.org>
Acked-by: default avatarJeremy Fitzhardinge <jeremy@xensource.com>
Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
parent 49a69787

arch/x86/kernel/time_64.c

+9 −3
Original line number Diff line number Diff line
@@ -21,6 +21,8 @@ 
#include <asm/hpet.h>

#include <asm/nmi.h>

#include <asm/vgtod.h>

#include <asm/time.h>

#include <asm/timer.h>



volatile unsigned long __jiffies __section_jiffies = INITIAL_JIFFIES;
@@ -54,7 +56,7 @@ static irqreturn_t timer_event_interrupt(int irq, void *dev_id) 
/* calibrate_cpu is used on systems with fixed rate TSCs to determine

 * processor frequency */

#define TICK_COUNT 100000000

static unsigned int __init tsc_calibrate_cpu_khz(void)

unsigned long __init native_calculate_cpu_khz(void)

{

	int tsc_start, tsc_now;

	int i, no_ctr_free;
@@ -104,20 +106,23 @@ static struct irqaction irq0 = { 
	.name		= "timer"

};



void __init time_init(void)

void __init hpet_time_init(void)

{

	if (!hpet_enable())

		setup_pit_timer();



	setup_irq(0, &irq0);

}



void __init time_init(void)

{

	tsc_calibrate();



	cpu_khz = tsc_khz;

	if (cpu_has(&boot_cpu_data, X86_FEATURE_CONSTANT_TSC) &&

		boot_cpu_data.x86_vendor == X86_VENDOR_AMD &&

		boot_cpu_data.x86 == 16)

		cpu_khz = tsc_calibrate_cpu_khz();

		cpu_khz = calculate_cpu_khz();



	if (unsynchronized_tsc())

		mark_tsc_unstable("TSCs unsynchronized");
@@ -130,4 +135,5 @@ void __init time_init(void) 
	printk(KERN_INFO "time.c: Detected %d.%03d MHz processor.\n",

		cpu_khz / 1000, cpu_khz % 1000);

	init_tsc_clocksource();

	late_time_init = choose_time_init();

}

include/asm-x86/time.h

+21 −5
Original line number Diff line number Diff line 
#ifndef _ASMi386_TIME_H

#define _ASMi386_TIME_H

#ifndef _ASMX86_TIME_H

#define _ASMX86_TIME_H



extern void (*late_time_init)(void);

extern void hpet_time_init(void);



#include <linux/efi.h>

#include <asm/mc146818rtc.h>

#ifdef CONFIG_X86_32

#include <linux/efi.h>



static inline unsigned long native_get_wallclock(void)

{
@@ -28,8 +32,20 @@ static inline int native_set_wallclock(unsigned long nowtime) 
	return retval;

}



extern void (*late_time_init)(void);

extern void hpet_time_init(void);

#else

extern void native_time_init_hook(void);



static inline unsigned long native_get_wallclock(void)

{

	return mach_get_cmos_time();

}



static inline int native_set_wallclock(unsigned long nowtime)

{

	return mach_set_rtc_mmss(nowtime);

}



#endif



#ifdef CONFIG_PARAVIRT

#include <asm/paravirt.h>

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