KVM guest: Add a pv_ops stub for steal time

This patch adds a function pointer in one of the many paravirt_ops
structs, to allow guests to register a steal time function. Besides
a steal time function, we also declare two jump_labels. They will be
used to allow the steal time code to be easily bypassed when not
in use.

Signed-off-by: Glauber Costa <glommer@redhat.com>
Acked-by: Rik van Riel <riel@redhat.com>
Tested-by: Eric B Munson <emunson@mgebm.net>
CC: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
CC: Peter Zijlstra <peterz@infradead.org>
CC: Anthony Liguori <aliguori@us.ibm.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
This commit is contained in:
Glauber Costa 2011-07-11 15:28:15 -04:00 committed by Avi Kivity
parent c9aaa8957f
commit 3c404b578f
3 changed files with 19 additions and 0 deletions

View File

@ -230,6 +230,15 @@ static inline unsigned long long paravirt_sched_clock(void)
return PVOP_CALL0(unsigned long long, pv_time_ops.sched_clock);
}
struct jump_label_key;
extern struct jump_label_key paravirt_steal_enabled;
extern struct jump_label_key paravirt_steal_rq_enabled;
static inline u64 paravirt_steal_clock(int cpu)
{
return PVOP_CALL1(u64, pv_time_ops.steal_clock, cpu);
}
static inline unsigned long long paravirt_read_pmc(int counter)
{
return PVOP_CALL1(u64, pv_cpu_ops.read_pmc, counter);

View File

@ -89,6 +89,7 @@ struct pv_lazy_ops {
struct pv_time_ops {
unsigned long long (*sched_clock)(void);
unsigned long long (*steal_clock)(int cpu);
unsigned long (*get_tsc_khz)(void);
};

View File

@ -202,6 +202,14 @@ static void native_flush_tlb_single(unsigned long addr)
__native_flush_tlb_single(addr);
}
struct jump_label_key paravirt_steal_enabled;
struct jump_label_key paravirt_steal_rq_enabled;
static u64 native_steal_clock(int cpu)
{
return 0;
}
/* These are in entry.S */
extern void native_iret(void);
extern void native_irq_enable_sysexit(void);
@ -307,6 +315,7 @@ struct pv_init_ops pv_init_ops = {
struct pv_time_ops pv_time_ops = {
.sched_clock = native_sched_clock,
.steal_clock = native_steal_clock,
};
struct pv_irq_ops pv_irq_ops = {