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sched/x86: Remove broken power estimation

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The x86 sched power implementation has been broken forever and gets in
the way of other stuff, remove it.

[ For archaeological interest, fixing this code would require dealing
  with the cross-cpu calling of these functions and more importantly, we
  need to filter idle time out of the a/m-perf stuff because the ratio
  will go down to 0 when idle, giving a 0 capacity which is not what
  we'd want. ]

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Link: http://lkml.kernel.org/r/1339594110.8980.38.camel@twins
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This commit is contained in:
Peter Zijlstra 2012-06-13 15:24:45 +02:00 committed by Ingo Molnar
parent 28a33cbc24
commit ee08d1284e
2 changed files with 1 additions and 56 deletions
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2
arch/x86/kernel/cpu/Makefile
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@ -14,7 +14,7 @@ CFLAGS_common.o := $(nostackp)
obj-y := intel_cacheinfo.o scattered.o topology.o
obj-y += proc.o capflags.o powerflags.o common.o
obj-y += vmware.o hypervisor.o sched.o mshyperv.o
obj-y += vmware.o hypervisor.o mshyperv.o
obj-y += rdrand.o
obj-y += match.o

55
arch/x86/kernel/cpu/sched.c
View File

@ -1,55 +0,0 @@
#include <linux/sched.h>
#include <linux/math64.h>
#include <linux/percpu.h>
#include <linux/irqflags.h>
#include <asm/cpufeature.h>
#include <asm/processor.h>
#ifdef CONFIG_SMP
static DEFINE_PER_CPU(struct aperfmperf, old_perf_sched);
static unsigned long scale_aperfmperf(void)
{
struct aperfmperf val, *old = &__get_cpu_var(old_perf_sched);
unsigned long ratio, flags;
local_irq_save(flags);
get_aperfmperf(&val);
local_irq_restore(flags);
ratio = calc_aperfmperf_ratio(old, &val);
*old = val;
return ratio;
}
unsigned long arch_scale_freq_power(struct sched_domain *sd, int cpu)
{
/*
* do aperf/mperf on the cpu level because it includes things
* like turbo mode, which are relevant to full cores.
*/
if (boot_cpu_has(X86_FEATURE_APERFMPERF))
return scale_aperfmperf();
/*
* maybe have something cpufreq here
*/
return default_scale_freq_power(sd, cpu);
}
unsigned long arch_scale_smt_power(struct sched_domain *sd, int cpu)
{
/*
* aperf/mperf already includes the smt gain
*/
if (boot_cpu_has(X86_FEATURE_APERFMPERF))
return SCHED_LOAD_SCALE;
return default_scale_smt_power(sd, cpu);
}
#endif