cpufreq: Remove unused APERF/MPERF support
The target frequency calculation method in the ondemand governor has
changed and it is now independent of the measured average frequency.
Consequently, the APERF/MPERF support in cpufreq is not used any
more, so drop it.
[rjw: Changelog]
Signed-off-by: Stratos Karafotis <stratosk@semaphore.gr>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h
index 24cf5ae..4f4a3d9 100644
--- a/arch/x86/include/asm/processor.h
+++ b/arch/x86/include/asm/processor.h
@@ -942,35 +942,6 @@
extern u16 amd_get_nb_id(int cpu);
-struct aperfmperf {
- u64 aperf, mperf;
-};
-
-static inline void get_aperfmperf(struct aperfmperf *am)
-{
- WARN_ON_ONCE(!boot_cpu_has(X86_FEATURE_APERFMPERF));
-
- rdmsrl(MSR_IA32_APERF, am->aperf);
- rdmsrl(MSR_IA32_MPERF, am->mperf);
-}
-
-#define APERFMPERF_SHIFT 10
-
-static inline
-unsigned long calc_aperfmperf_ratio(struct aperfmperf *old,
- struct aperfmperf *new)
-{
- u64 aperf = new->aperf - old->aperf;
- u64 mperf = new->mperf - old->mperf;
- unsigned long ratio = aperf;
-
- mperf >>= APERFMPERF_SHIFT;
- if (mperf)
- ratio = div64_u64(aperf, mperf);
-
- return ratio;
-}
-
extern unsigned long arch_align_stack(unsigned long sp);
extern void free_init_pages(char *what, unsigned long begin, unsigned long end);
diff --git a/drivers/cpufreq/Makefile b/drivers/cpufreq/Makefile
index d345b5a..ad5866c 100644
--- a/drivers/cpufreq/Makefile
+++ b/drivers/cpufreq/Makefile
@@ -23,7 +23,7 @@
# powernow-k8 can load then. ACPI is preferred to all other hardware-specific drivers.
# speedstep-* is preferred over p4-clockmod.
-obj-$(CONFIG_X86_ACPI_CPUFREQ) += acpi-cpufreq.o mperf.o
+obj-$(CONFIG_X86_ACPI_CPUFREQ) += acpi-cpufreq.o
obj-$(CONFIG_X86_POWERNOW_K8) += powernow-k8.o
obj-$(CONFIG_X86_PCC_CPUFREQ) += pcc-cpufreq.o
obj-$(CONFIG_X86_POWERNOW_K6) += powernow-k6.o
diff --git a/drivers/cpufreq/acpi-cpufreq.c b/drivers/cpufreq/acpi-cpufreq.c
index 3926402..e673670 100644
--- a/drivers/cpufreq/acpi-cpufreq.c
+++ b/drivers/cpufreq/acpi-cpufreq.c
@@ -45,7 +45,6 @@
#include <asm/msr.h>
#include <asm/processor.h>
#include <asm/cpufeature.h>
-#include "mperf.h"
MODULE_AUTHOR("Paul Diefenbaugh, Dominik Brodowski");
MODULE_DESCRIPTION("ACPI Processor P-States Driver");
@@ -861,10 +860,6 @@
/* notify BIOS that we exist */
acpi_processor_notify_smm(THIS_MODULE);
- /* Check for APERF/MPERF support in hardware */
- if (boot_cpu_has(X86_FEATURE_APERFMPERF))
- acpi_cpufreq_driver.getavg = cpufreq_get_measured_perf;
-
pr_debug("CPU%u - ACPI performance management activated.\n", cpu);
for (i = 0; i < perf->state_count; i++)
pr_debug(" %cP%d: %d MHz, %d mW, %d uS\n",
diff --git a/drivers/cpufreq/mperf.c b/drivers/cpufreq/mperf.c
deleted file mode 100644
index 911e193..0000000
--- a/drivers/cpufreq/mperf.c
+++ /dev/null
@@ -1,51 +0,0 @@
-#include <linux/kernel.h>
-#include <linux/smp.h>
-#include <linux/module.h>
-#include <linux/init.h>
-#include <linux/cpufreq.h>
-#include <linux/slab.h>
-
-#include "mperf.h"
-
-static DEFINE_PER_CPU(struct aperfmperf, acfreq_old_perf);
-
-/* Called via smp_call_function_single(), on the target CPU */
-static void read_measured_perf_ctrs(void *_cur)
-{
- struct aperfmperf *am = _cur;
-
- get_aperfmperf(am);
-}
-
-/*
- * Return the measured active (C0) frequency on this CPU since last call
- * to this function.
- * Input: cpu number
- * Return: Average CPU frequency in terms of max frequency (zero on error)
- *
- * We use IA32_MPERF and IA32_APERF MSRs to get the measured performance
- * over a period of time, while CPU is in C0 state.
- * IA32_MPERF counts at the rate of max advertised frequency
- * IA32_APERF counts at the rate of actual CPU frequency
- * Only IA32_APERF/IA32_MPERF ratio is architecturally defined and
- * no meaning should be associated with absolute values of these MSRs.
- */
-unsigned int cpufreq_get_measured_perf(struct cpufreq_policy *policy,
- unsigned int cpu)
-{
- struct aperfmperf perf;
- unsigned long ratio;
- unsigned int retval;
-
- if (smp_call_function_single(cpu, read_measured_perf_ctrs, &perf, 1))
- return 0;
-
- ratio = calc_aperfmperf_ratio(&per_cpu(acfreq_old_perf, cpu), &perf);
- per_cpu(acfreq_old_perf, cpu) = perf;
-
- retval = (policy->cpuinfo.max_freq * ratio) >> APERFMPERF_SHIFT;
-
- return retval;
-}
-EXPORT_SYMBOL_GPL(cpufreq_get_measured_perf);
-MODULE_LICENSE("GPL");
diff --git a/drivers/cpufreq/mperf.h b/drivers/cpufreq/mperf.h
deleted file mode 100644
index 5dbf295..0000000
--- a/drivers/cpufreq/mperf.h
+++ /dev/null
@@ -1,9 +0,0 @@
-/*
- * (c) 2010 Advanced Micro Devices, Inc.
- * Your use of this code is subject to the terms and conditions of the
- * GNU general public license version 2. See "COPYING" or
- * http://www.gnu.org/licenses/gpl.html
- */
-
-unsigned int cpufreq_get_measured_perf(struct cpufreq_policy *policy,
- unsigned int cpu);