Mailing List Archive

[xen-unstable] cpuidle: reduce redundant cost in cstate_restore_tsc for nonstop tsc
# HG changeset patch
# User Keir Fraser <keir.fraser@citrix.com>
# Date 1276761055 -3600
# Node ID 6fffbb86acae27f5a742884b5d3b5a5c73b4ed15
# Parent 7a00c0bd4fc131fb4de5df9f3fdc4e48a29dd5f9
cpuidle: reduce redundant cost in cstate_restore_tsc for nonstop tsc

Signed-off-by: Wei Gang <gang.wei@intel.com>
---
xen/arch/x86/time.c | 7 +++++--
1 files changed, 5 insertions(+), 2 deletions(-)

diff -r 7a00c0bd4fc1 -r 6fffbb86acae xen/arch/x86/time.c
--- a/xen/arch/x86/time.c Thu Jun 17 08:50:18 2010 +0100
+++ b/xen/arch/x86/time.c Thu Jun 17 08:50:55 2010 +0100
@@ -664,13 +664,16 @@ static void __init init_platform_timer(v

void cstate_restore_tsc(void)
{
- struct cpu_time *t = &this_cpu(cpu_time);
- struct time_scale sys_to_tsc = scale_reciprocal(t->tsc_scale);
+ struct cpu_time *t;
+ struct time_scale sys_to_tsc;
s_time_t stime_delta;
u64 new_tsc;

if ( boot_cpu_has(X86_FEATURE_NONSTOP_TSC) )
return;
+
+ t = &this_cpu(cpu_time);
+ sys_to_tsc = scale_reciprocal(t->tsc_scale);

stime_delta = read_platform_stime() - t->stime_master_stamp;
if ( stime_delta < 0 )

_______________________________________________
Xen-changelog mailing list
Xen-changelog@lists.xensource.com
http://lists.xensource.com/xen-changelog