commit d82a8035d09bcfcac238b80ad97335167665a7c3
author Amit Pundir <amit.pundir@linaro.org> Thu Feb 23 16:02:45 2017 -0800
committer Amit Pundir <amit.pundir@linaro.org> Fri Sep 14 00:30:54 2018 +0530
tree eec2069a95cdff0a4de9cf215d9b4365dac384a9
parent 441e17f79c4a092bba3450b8b4d4eeec7e5d6729

ANDROID: idle_notifier: Add generic idle notifiers

AOSP Change-ID: Idf29cda15be151f494ff245933c12462643388d5
moved x86_64 idle notifiers as generic so that they can
be used in interactive governor.

Upstream change 8e7a7ee9ddd5 ("x86/idle: Remove idle_notifier")
removed x86_64 idle notifiers altogether. This patch add
generic idle notifiers again.

Fixes: android-4.9 commit bfd2a547fc17 ("ANDROID: ARM: Call idle notifiers")
Signed-off-by: Amit Pundir <amit.pundir@linaro.org>

include/linux/cpu.h

diff --git a/include/linux/cpu.h b/include/linux/cpu.h
index 218df7f..1bf10aa 100644
--- a/include/linux/cpu.h
+++ b/include/linux/cpu.h
@@ -189,4 +189,11 @@
 static inline void cpu_smt_check_topology(void) { }
 #endif
 
+#define IDLE_START 1
+#define IDLE_END 2
+
+void idle_notifier_register(struct notifier_block *n);
+void idle_notifier_unregister(struct notifier_block *n);
+void idle_notifier_call_chain(unsigned long val);
+
 #endif /* _LINUX_CPU_H_ */

kernel/cpu.c

diff --git a/kernel/cpu.c b/kernel/cpu.c
index f3f6250..5198135 100644
--- a/kernel/cpu.c
+++ b/kernel/cpu.c
@@ -2290,3 +2290,23 @@
 #endif
 	this_cpu_write(cpuhp_state.state, CPUHP_ONLINE);
 }
+
+static ATOMIC_NOTIFIER_HEAD(idle_notifier);
+
+void idle_notifier_register(struct notifier_block *n)
+{
+	atomic_notifier_chain_register(&idle_notifier, n);
+}
+EXPORT_SYMBOL_GPL(idle_notifier_register);
+
+void idle_notifier_unregister(struct notifier_block *n)
+{
+	atomic_notifier_chain_unregister(&idle_notifier, n);
+}
+EXPORT_SYMBOL_GPL(idle_notifier_unregister);
+
+void idle_notifier_call_chain(unsigned long val)
+{
+	atomic_notifier_call_chain(&idle_notifier, val, NULL);
+}
+EXPORT_SYMBOL_GPL(idle_notifier_call_chain);