[PATCH] [26/34] i386: remove xtime_lock'ing around cpufreq notifier

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From: Daniel Walker <[email protected]>

The locking of the xtime_lock around the cpu notifier is unessesary now. 
At one time the tsc was used after a frequency change for timekeeping, but
the re-write of timekeeping no longer uses the TSC unless the frequency is
constant.

The variables that are changed in this section of code had also once been
used for timekeeping, but not any longer ..

Signed-off-by: Daniel Walker <[email protected]>
Signed-off-by: Andi Kleen <[email protected]>
Cc: Andi Kleen <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: john stultz <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
---

 arch/i386/kernel/tsc.c |    8 +-------
 1 file changed, 1 insertion(+), 7 deletions(-)

Index: linux/arch/i386/kernel/tsc.c
===================================================================
--- linux.orig/arch/i386/kernel/tsc.c
+++ linux/arch/i386/kernel/tsc.c
@@ -144,13 +144,10 @@ time_cpufreq_notifier(struct notifier_bl
 {
 	struct cpufreq_freqs *freq = data;
 
-	if (val != CPUFREQ_RESUMECHANGE && val != CPUFREQ_SUSPENDCHANGE)
-		write_seqlock_irq(&xtime_lock);
-
 	if (!ref_freq) {
 		if (!freq->old){
 			ref_freq = freq->new;
-			goto end;
+			return 0;
 		}
 		ref_freq = freq->old;
 		loops_per_jiffy_ref = cpu_data[freq->cpu].loops_per_jiffy;
@@ -176,9 +173,6 @@ time_cpufreq_notifier(struct notifier_bl
 			}
 		}
 	}
-end:
-	if (val != CPUFREQ_RESUMECHANGE && val != CPUFREQ_SUSPENDCHANGE)
-		write_sequnlock_irq(&xtime_lock);
 
 	return 0;
 }
-
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