Merge branch 'pm-cpufreq'

* pm-cpufreq: (63 commits)
  intel_pstate: Clean up get_target_pstate_use_performance()
  intel_pstate: Use sample.core_avg_perf in get_avg_pstate()
  intel_pstate: Clarify average performance computation
  intel_pstate: Avoid unnecessary synchronize_sched() during initialization
  cpufreq: schedutil: Make default depend on CONFIG_SMP
  cpufreq: powernv: del_timer_sync when global and local pstate are equal
  cpufreq: powernv: Move smp_call_function_any() out of irq safe block
  intel_pstate: Clean up intel_pstate_get()
  cpufreq: schedutil: Make it depend on CONFIG_SMP
  cpufreq: governor: Fix handling of special cases in dbs_update()
  cpufreq: intel_pstate: Ignore _PPC processing under HWP
  cpufreq: arm_big_little: use generic OPP functions for {init, free}_opp_table
  cpufreq: tango: Use generic platdev driver
  cpufreq: Fix GOV_LIMITS handling for the userspace governor
  cpufreq: mvebu: Move cpufreq code into drivers/cpufreq/
  cpufreq: dt: Kill platform-data
  mvebu: Use dev_pm_opp_set_sharing_cpus() to mark OPP tables as shared
  cpufreq: dt: Identify cpu-sharing for platforms without operating-points-v2
  cpufreq: governor: Change confusing struct field and variable names
  cpufreq: intel_pstate: Enable PPC enforcement for servers
  ...

1 files changed, 37 insertions, 11 deletions

diff --git a/kernel/sched/cpufreq.c b/kernel/sched/cpufreq.c
index 928c4ba32f68..1141954e73b4 100644
--- a/kernel/sched/cpufreq.c
+++ b/kernel/sched/cpufreq.c
@@ -14,24 +14,50 @@
 DEFINE_PER_CPU(struct update_util_data *, cpufreq_update_util_data);
 
 /**
- * cpufreq_set_update_util_data - Populate the CPU's update_util_data pointer.
+ * cpufreq_add_update_util_hook - Populate the CPU's update_util_data pointer.
  * @cpu: The CPU to set the pointer for.
  * @data: New pointer value.
+ * @func: Callback function to set for the CPU.
  *
- * Set and publish the update_util_data pointer for the given CPU.  That pointer
- * points to a struct update_util_data object containing a callback function
- * to call from cpufreq_update_util().  That function will be called from an RCU
- * read-side critical section, so it must not sleep.
+ * Set and publish the update_util_data pointer for the given CPU.
  *
- * Callers must use RCU-sched callbacks to free any memory that might be
- * accessed via the old update_util_data pointer or invoke synchronize_sched()
- * right after this function to avoid use-after-free.
+ * The update_util_data pointer of @cpu is set to @data and the callback
+ * function pointer in the target struct update_util_data is set to @func.
+ * That function will be called by cpufreq_update_util() from RCU-sched
+ * read-side critical sections, so it must not sleep.  @data will always be
+ * passed to it as the first argument which allows the function to get to the
+ * target update_util_data structure and its container.
+ *
+ * The update_util_data pointer of @cpu must be NULL when this function is
+ * called or it will WARN() and return with no effect.
  */
-void cpufreq_set_update_util_data(int cpu, struct update_util_data *data)
+void cpufreq_add_update_util_hook(int cpu, struct update_util_data *data,
+			void (*func)(struct update_util_data *data, u64 time,
+				     unsigned long util, unsigned long max))
 {
-	if (WARN_ON(data && !data->func))
+	if (WARN_ON(!data || !func))
 		return;
 
+	if (WARN_ON(per_cpu(cpufreq_update_util_data, cpu)))
+		return;
+
+	data->func = func;
 	rcu_assign_pointer(per_cpu(cpufreq_update_util_data, cpu), data);
 }
-EXPORT_SYMBOL_GPL(cpufreq_set_update_util_data);
+EXPORT_SYMBOL_GPL(cpufreq_add_update_util_hook);
+
+/**
+ * cpufreq_remove_update_util_hook - Clear the CPU's update_util_data pointer.
+ * @cpu: The CPU to clear the pointer for.
+ *
+ * Clear the update_util_data pointer for the given CPU.
+ *
+ * Callers must use RCU-sched callbacks to free any memory that might be
+ * accessed via the old update_util_data pointer or invoke synchronize_sched()
+ * right after this function to avoid use-after-free.
+ */
+void cpufreq_remove_update_util_hook(int cpu)
+{
+	rcu_assign_pointer(per_cpu(cpufreq_update_util_data, cpu), NULL);
+}
+EXPORT_SYMBOL_GPL(cpufreq_remove_update_util_hook);