diff options
author | Isaku Yamahata <yamahata@valinux.co.jp> | 2009-03-04 07:05:40 -0500 |
---|---|---|
committer | Tony Luck <tony.luck@intel.com> | 2009-03-26 13:50:42 -0400 |
commit | f927da178671a824cf6c530f0623544206387e57 (patch) | |
tree | fb9178ff79bfd9ee3b396ff20018eacbfb222d47 /arch/ia64/kernel/head.S | |
parent | 496203b15b7249599712525c2b6aafe231b4628d (diff) |
ia64/pv_ops/pv_time_ops: add sched_clock hook.
add sched_clock() hook to paravirtualize sched_clock().
ia64 sched_clock() is based on ar.itc which isn't stable
on virtualized environment because vcpu may move around on
pcpus. So it needs paravirtualization.
Signed-off-by: Isaku Yamahata <yamahata@valinux.co.jp>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Diffstat (limited to 'arch/ia64/kernel/head.S')
-rw-r--r-- | arch/ia64/kernel/head.S | 10 |
1 files changed, 8 insertions, 2 deletions
diff --git a/arch/ia64/kernel/head.S b/arch/ia64/kernel/head.S index 59301c472800..23f846de62d5 100644 --- a/arch/ia64/kernel/head.S +++ b/arch/ia64/kernel/head.S | |||
@@ -1050,7 +1050,7 @@ END(ia64_delay_loop) | |||
1050 | * except that the multiplication and the shift are done with 128-bit | 1050 | * except that the multiplication and the shift are done with 128-bit |
1051 | * intermediate precision so that we can produce a full 64-bit result. | 1051 | * intermediate precision so that we can produce a full 64-bit result. |
1052 | */ | 1052 | */ |
1053 | GLOBAL_ENTRY(sched_clock) | 1053 | GLOBAL_ENTRY(ia64_native_sched_clock) |
1054 | addl r8=THIS_CPU(cpu_info) + IA64_CPUINFO_NSEC_PER_CYC_OFFSET,r0 | 1054 | addl r8=THIS_CPU(cpu_info) + IA64_CPUINFO_NSEC_PER_CYC_OFFSET,r0 |
1055 | mov.m r9=ar.itc // fetch cycle-counter (35 cyc) | 1055 | mov.m r9=ar.itc // fetch cycle-counter (35 cyc) |
1056 | ;; | 1056 | ;; |
@@ -1066,7 +1066,13 @@ GLOBAL_ENTRY(sched_clock) | |||
1066 | ;; | 1066 | ;; |
1067 | shrp r8=r9,r8,IA64_NSEC_PER_CYC_SHIFT | 1067 | shrp r8=r9,r8,IA64_NSEC_PER_CYC_SHIFT |
1068 | br.ret.sptk.many rp | 1068 | br.ret.sptk.many rp |
1069 | END(sched_clock) | 1069 | END(ia64_native_sched_clock) |
1070 | #ifndef CONFIG_PARAVIRT | ||
1071 | //unsigned long long | ||
1072 | //sched_clock(void) __attribute__((alias("ia64_native_sched_clock"))); | ||
1073 | .global sched_clock | ||
1074 | sched_clock = ia64_native_sched_clock | ||
1075 | #endif | ||
1070 | 1076 | ||
1071 | #ifdef CONFIG_VIRT_CPU_ACCOUNTING | 1077 | #ifdef CONFIG_VIRT_CPU_ACCOUNTING |
1072 | GLOBAL_ENTRY(cycle_to_cputime) | 1078 | GLOBAL_ENTRY(cycle_to_cputime) |