cpufreq/intel_pstate: Use CPPC to get max performance

Use the acpi cppc_lib interface to get CPPC performance limits and update
the per cpu priority for the ITMT scheduler. If the highest performance of
CPUs differs the ITMT feature is enabled.

Co-developed-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Tim Chen <tim.c.chen@linux.intel.com>
Cc: linux-pm@vger.kernel.org
Cc: peterz@infradead.org
Cc: jolsa@redhat.com
Cc: rjw@rjwysocki.net
Cc: linux-acpi@vger.kernel.org
Cc: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Cc: bp@suse.de
Link: http://lkml.kernel.org/r/0998b98943bcdec7d1ddd4ff27358da555ea8e92.1479844244.git.tim.c.chen@linux.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This commit is contained in:
Rafael J. Wysocki 2016-11-22 12:24:00 -08:00 committed by Thomas Gleixner
parent 8b533a0eee
commit 17669006ad
2 changed files with 56 additions and 1 deletions

View File

@ -6,6 +6,7 @@ config X86_INTEL_PSTATE
bool "Intel P state control"
depends on X86
select ACPI_PROCESSOR if ACPI
select ACPI_CPPC_LIB if X86_64 && ACPI && SCHED_ITMT
help
This driver provides a P state for Intel core processors.
The driver implements an internal governor and will become

View File

@ -44,6 +44,7 @@
#ifdef CONFIG_ACPI
#include <acpi/processor.h>
#include <acpi/cppc_acpi.h>
#endif
#define FRAC_BITS 8
@ -379,14 +380,67 @@ static bool intel_pstate_get_ppc_enable_status(void)
return acpi_ppc;
}
#ifdef CONFIG_ACPI_CPPC_LIB
/* The work item is needed to avoid CPU hotplug locking issues */
static void intel_pstste_sched_itmt_work_fn(struct work_struct *work)
{
sched_set_itmt_support();
}
static DECLARE_WORK(sched_itmt_work, intel_pstste_sched_itmt_work_fn);
static void intel_pstate_set_itmt_prio(int cpu)
{
struct cppc_perf_caps cppc_perf;
static u32 max_highest_perf = 0, min_highest_perf = U32_MAX;
int ret;
ret = cppc_get_perf_caps(cpu, &cppc_perf);
if (ret)
return;
/*
* The priorities can be set regardless of whether or not
* sched_set_itmt_support(true) has been called and it is valid to
* update them at any time after it has been called.
*/
sched_set_itmt_core_prio(cppc_perf.highest_perf, cpu);
if (max_highest_perf <= min_highest_perf) {
if (cppc_perf.highest_perf > max_highest_perf)
max_highest_perf = cppc_perf.highest_perf;
if (cppc_perf.highest_perf < min_highest_perf)
min_highest_perf = cppc_perf.highest_perf;
if (max_highest_perf > min_highest_perf) {
/*
* This code can be run during CPU online under the
* CPU hotplug locks, so sched_set_itmt_support()
* cannot be called from here. Queue up a work item
* to invoke it.
*/
schedule_work(&sched_itmt_work);
}
}
}
#else
static void intel_pstate_set_itmt_prio(int cpu)
{
}
#endif
static void intel_pstate_init_acpi_perf_limits(struct cpufreq_policy *policy)
{
struct cpudata *cpu;
int ret;
int i;
if (hwp_active)
if (hwp_active) {
intel_pstate_set_itmt_prio(policy->cpu);
return;
}
if (!intel_pstate_get_ppc_enable_status())
return;