x86: allow sched clock to be overridden by paravirt

This patch turns the sched_clock into native_sched_clock.
sched clock becomes a weak symbol, which can then give its
place to a paravirt definition.

Signed-off-by: Glauber de Oliveira Costa <gcosta@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This commit is contained in:
Glauber de Oliveira Costa 2008-01-30 13:31:03 +01:00 committed by Ingo Molnar
parent 751de83c0c
commit 16e2011be6

View file

@ -63,7 +63,7 @@ static void set_cyc2ns_scale(unsigned long cpu_khz, int cpu)
local_irq_restore(flags);
}
unsigned long long sched_clock(void)
unsigned long long native_sched_clock(void)
{
unsigned long a = 0;
@ -77,6 +77,19 @@ unsigned long long sched_clock(void)
return cycles_2_ns(a);
}
/* We need to define a real function for sched_clock, to override the
weak default version */
#ifdef CONFIG_PARAVIRT
unsigned long long sched_clock(void)
{
return paravirt_sched_clock();
}
#else
unsigned long long
sched_clock(void) __attribute__((alias("native_sched_clock")));
#endif
static int tsc_unstable;
inline int check_tsc_unstable(void)