Re: [PATCH v3 3/4] sched: scheduler-driven cpu frequency selection

Hi Mike,

On 27/06/15 00:53, Michael Turquette wrote:

From: Michael Turquette <mturquette@baylibre.com>

[...]

To get it building with CONFIG_CPU_FREQ_DEFAULT_GOV_SCHED=y .

-#elif defined(CONFIG_CPU_FREQ_DEFAULT_GOV_SCHED_GOV)
-extern struct cpufreq_governor cpufreq_gov_sched_gov;
+#elif defined(CONFIG_CPU_FREQ_DEFAULT_GOV_SCHED)
+extern struct cpufreq_governor cpufreq_gov_sched;

+#define CPUFREQ_DEFAULT_GOVERNOR       (&cpufreq_gov_sched)
 #endif

+
+/**
+ * cpufreq_sched_set_capacity - interface to scheduler for changing capacity values

[...]

minor nit:

s/cpufreq_sched_set_capacity/cpufreq_sched_set_cap

+ * @cpu: cpu whose capacity utilization has recently changed
+ * @capacity: the new capacity requested by cpu
+ *
+ * cpufreq_sched_sched_capacity is an interface exposed to the scheduler so
+ * that the scheduler may inform the governor of updates to capacity
+ * utilization and make changes to cpu frequency. Currently this interface is
+ * designed around PELT values in CFS. It can be expanded to other scheduling
+ * classes in the future if needed.
+ *
+ * cpufreq_sched_set_capacity raises an IPI. The irq_work handler for that IPI
+ * wakes up the thread that does the actual work, cpufreq_sched_thread.
+ *
+ * This functions bails out early if either condition is true:
+ * 1) this cpu did not the new maximum capacity for its frequency domain
+ * 2) no change in cpu frequency is necessary to meet the new capacity request
+ */
+void cpufreq_sched_set_cap(int cpu, unsigned long capacity)
+{
+       unsigned int freq_new, cpu_tmp;
+       struct cpufreq_policy *policy;
+       struct gov_data *gd;
+       unsigned long capacity_max = 0;

[...]