[PATCH] vmi: cpu cycles fix

In order to share the common code in tsc.c which does CPU Khz calibration, we
need to make an accurate value of CPU speed available to the tsc.c code.  This
value loses a lot of precision in a VM because of the timing differences with
real hardware, but we need it to be as precise as possible so the guest can
make accurate time calculations with the cycle counters.

Signed-off-by: Zachary Amsden <zach@vmware.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Zachary Amsden
2007-03-05 00:30:36 -08:00
committed by Linus Torvalds
parent 6cb9a8350a
commit 1182d8528b
7 changed files with 17 additions and 2 deletions

View File

@@ -7,6 +7,7 @@
void setup_pit_timer(void);
unsigned long long native_sched_clock(void);
unsigned long native_calculate_cpu_khz(void);
/* Modifiers for buggy PIT handling */
extern int pit_latch_buggy;
@@ -17,6 +18,7 @@ extern int recalibrate_cpu_khz(void);
#ifndef CONFIG_PARAVIRT
#define get_scheduled_cycles(val) rdtscll(val)
#define calculate_cpu_khz() native_calculate_cpu_khz()
#endif
#endif