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authorLinus Torvalds <torvalds@woody.linux-foundation.org>2007-07-18 10:18:39 -0700
committerLinus Torvalds <torvalds@woody.linux-foundation.org>2007-07-18 10:18:39 -0700
commit5cc97bf2d8eaa6cab60727c3eba3e85e29062669 (patch)
tree975976f2cb37b932d65440e6fb9960be93fc0bd7 /arch/i386/kernel/tsc.c
parent826ea8f22cf612d534f33c492c98f7895043bfd1 (diff)
parentdfdcdd42fdf63452ddd1bed6f49ae2a35dfb5d6c (diff)
Merge branch 'xen-upstream' of ssh://master.kernel.org/pub/scm/linux/kernel/git/jeremy/xen
* 'xen-upstream' of ssh://master.kernel.org/pub/scm/linux/kernel/git/jeremy/xen: (44 commits) xen: disable all non-virtual drivers xen: use iret directly when possible xen: suppress abs symbol warnings for unused reloc pointers xen: Attempt to patch inline versions of common operations xen: Place vcpu_info structure into per-cpu memory xen: handle external requests for shutdown, reboot and sysrq xen: machine operations xen: add virtual network device driver xen: add virtual block device driver. xen: add the Xenbus sysfs and virtual device hotplug driver xen: Add grant table support xen: use the hvc console infrastructure for Xen console xen: hack to prevent bad segment register reload xen: lazy-mmu operations xen: Add support for preemption xen: SMP guest support xen: Implement sched_clock xen: Account for stolen time xen: ignore RW mapping of RO pages in pagetable_init xen: Complete pagetable pinning ...
Diffstat (limited to 'arch/i386/kernel/tsc.c')
-rw-r--r--arch/i386/kernel/tsc.c23
1 files changed, 15 insertions, 8 deletions
diff --git a/arch/i386/kernel/tsc.c b/arch/i386/kernel/tsc.c
index ea63a30ca3e..252f9010f28 100644
--- a/arch/i386/kernel/tsc.c
+++ b/arch/i386/kernel/tsc.c
@@ -84,7 +84,7 @@ static inline int check_tsc_unstable(void)
*
* -johnstul@us.ibm.com "math is hard, lets go shopping!"
*/
-static unsigned long cyc2ns_scale __read_mostly;
+unsigned long cyc2ns_scale __read_mostly;
#define CYC2NS_SCALE_FACTOR 10 /* 2^10, carefully chosen */
@@ -93,15 +93,10 @@ static inline void set_cyc2ns_scale(unsigned long cpu_khz)
cyc2ns_scale = (1000000 << CYC2NS_SCALE_FACTOR)/cpu_khz;
}
-static inline unsigned long long cycles_2_ns(unsigned long long cyc)
-{
- return (cyc * cyc2ns_scale) >> CYC2NS_SCALE_FACTOR;
-}
-
/*
* Scheduler clock - returns current time in nanosec units.
*/
-unsigned long long sched_clock(void)
+unsigned long long native_sched_clock(void)
{
unsigned long long this_offset;
@@ -118,12 +113,24 @@ unsigned long long sched_clock(void)
return (jiffies_64 - INITIAL_JIFFIES) * (1000000000 / HZ);
/* read the Time Stamp Counter: */
- get_scheduled_cycles(this_offset);
+ rdtscll(this_offset);
/* return the value in ns */
return cycles_2_ns(this_offset);
}
+/* 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
+
unsigned long native_calculate_cpu_khz(void)
{
unsigned long long start, end;