alistair23-linux/arch/x86/kernel/time.c
Andy Lutomirski 61a492fb17 x86_64/vdso: Remove jiffies from the vvar page
I think that the jiffies vvar was once used for the vgetcpu
cache. That code is long gone, so let's just make jiffies be a
normal variable.

Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Link: http://lkml.kernel.org/r/fcfee6f8749af14d96373a9e2656354ad0b95499.1411494540.git.luto@amacapital.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-10-28 11:22:13 +01:00

98 lines
2.1 KiB
C

/*
* Copyright (c) 1991,1992,1995 Linus Torvalds
* Copyright (c) 1994 Alan Modra
* Copyright (c) 1995 Markus Kuhn
* Copyright (c) 1996 Ingo Molnar
* Copyright (c) 1998 Andrea Arcangeli
* Copyright (c) 2002,2006 Vojtech Pavlik
* Copyright (c) 2003 Andi Kleen
*
*/
#include <linux/clockchips.h>
#include <linux/interrupt.h>
#include <linux/i8253.h>
#include <linux/time.h>
#include <linux/export.h>
#include <asm/vsyscall.h>
#include <asm/x86_init.h>
#include <asm/i8259.h>
#include <asm/timer.h>
#include <asm/hpet.h>
#include <asm/time.h>
#ifdef CONFIG_X86_64
__visible volatile unsigned long jiffies __cacheline_aligned = INITIAL_JIFFIES;
#endif
unsigned long profile_pc(struct pt_regs *regs)
{
unsigned long pc = instruction_pointer(regs);
if (!user_mode_vm(regs) && in_lock_functions(pc)) {
#ifdef CONFIG_FRAME_POINTER
return *(unsigned long *)(regs->bp + sizeof(long));
#else
unsigned long *sp =
(unsigned long *)kernel_stack_pointer(regs);
/*
* Return address is either directly at stack pointer
* or above a saved flags. Eflags has bits 22-31 zero,
* kernel addresses don't.
*/
if (sp[0] >> 22)
return sp[0];
if (sp[1] >> 22)
return sp[1];
#endif
}
return pc;
}
EXPORT_SYMBOL(profile_pc);
/*
* Default timer interrupt handler for PIT/HPET
*/
static irqreturn_t timer_interrupt(int irq, void *dev_id)
{
global_clock_event->event_handler(global_clock_event);
return IRQ_HANDLED;
}
static struct irqaction irq0 = {
.handler = timer_interrupt,
.flags = IRQF_NOBALANCING | IRQF_IRQPOLL | IRQF_TIMER,
.name = "timer"
};
void __init setup_default_timer_irq(void)
{
if (!nr_legacy_irqs())
return;
setup_irq(0, &irq0);
}
/* Default timer init function */
void __init hpet_time_init(void)
{
if (!hpet_enable())
setup_pit_timer();
setup_default_timer_irq();
}
static __init void x86_late_time_init(void)
{
x86_init.timers.timer_init();
tsc_init();
}
/*
* Initialize TSC and delay the periodic timer init to
* late x86_late_time_init() so ioremap works.
*/
void __init time_init(void)
{
late_time_init = x86_late_time_init;
}