ANDROID: cpufreq: Add a restricted vendor hook for freq transition

A restricted vendor hook for cpufreq transition. The hook is
invoked per policy after changing the policy->cur and passes
policy as an argument.

Bug: 181889516
Change-Id: I6f89850779fdd63e178e227c293f42b7f66fd78d
Signed-off-by: Pavankumar Kondeti <quic_pkondeti@quicinc.com>

drivers/android/vendor_hooks.c

@@ -162,3 +162,4 @@ EXPORT_TRACEPOINT_SYMBOL_GPL(android_vh_update_topology_flags_workfn);
 EXPORT_TRACEPOINT_SYMBOL_GPL(android_rvh_sched_balance_rt);
 EXPORT_TRACEPOINT_SYMBOL_GPL(android_rvh_pick_next_entity);
 EXPORT_TRACEPOINT_SYMBOL_GPL(android_rvh_check_preempt_wakeup);
+EXPORT_TRACEPOINT_SYMBOL_GPL(android_rvh_cpufreq_transition);

drivers/cpufreq/cpufreq.c

@@ -390,6 +390,7 @@ static void cpufreq_notify_transition(struct cpufreq_policy *policy,
 		cpufreq_stats_record_transition(policy, freqs->new);
 		cpufreq_times_record_transition(policy, freqs->new);
 		policy->cur = freqs->new;
+		trace_android_rvh_cpufreq_transition(policy);
 	}
 }
 
@@ -2111,6 +2112,7 @@ unsigned int cpufreq_driver_fast_switch(struct cpufreq_policy *policy,
 	arch_set_freq_scale(policy->related_cpus, freq,
 			    policy->cpuinfo.max_freq);
 	cpufreq_stats_record_transition(policy, freq);
+	trace_android_rvh_cpufreq_transition(policy);
 
 	if (trace_cpu_frequency_enabled()) {
 		for_each_cpu(cpu, policy->cpus)

include/trace/hooks/cpufreq.h

@@ -20,6 +20,10 @@ DECLARE_HOOK(android_vh_freq_table_limits,
 		 unsigned int max_freq),
 	TP_ARGS(policy, min_freq, max_freq));
 
+DECLARE_RESTRICTED_HOOK(android_rvh_cpufreq_transition,
+	TP_PROTO(struct cpufreq_policy *policy),
+	TP_ARGS(policy), 1);
+
 #endif /* _TRACE_HOOK_CPUFREQ_H */
 /* This part must be outside protection */
 #include <trace/define_trace.h>