diff options
author | Stratos Karafotis <stratosk@semaphore.gr> | 2013-06-05 19:01:42 +0300 |
---|---|---|
committer | Rafael J. Wysocki <rafael.j.wysocki@intel.com> | 2013-07-26 01:06:43 +0200 |
commit | 61c63e5ed3b9c472899d7152e961f2ffaafcf5a0 (patch) | |
tree | e84b694d4640fd0e1ba527ec63e41e3edfddeb04 /drivers/cpufreq/mperf.c | |
parent | dfa5bb622555d9da0df21b50f46ebdeef390041b (diff) |
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>
Diffstat (limited to 'drivers/cpufreq/mperf.c')
-rw-r--r-- | drivers/cpufreq/mperf.c | 51 |
1 files changed, 0 insertions, 51 deletions
diff --git a/drivers/cpufreq/mperf.c b/drivers/cpufreq/mperf.c deleted file mode 100644 index 911e193018ae..000000000000 --- 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"); |