Merge "idle: Implement a per-cpu idle-polling mode" (b3491934) · Commits · e / devices / android_kernel_sony_msm8994

include/linux/cpu.h

+1 −0

Original line number	Diff line number	Diff line
		@@ -288,6 +288,7 @@ void cpu_startup_entry(enum cpuhp_state state);
		void cpu_idle(void);

		void cpu_idle_poll_ctrl(bool enable);
		void per_cpu_idle_poll_ctrl(int cpu, bool enable);

		void arch_cpu_idle(void);
		void arch_cpu_idle_prepare(void);

kernel/cpu/idle.c

+25 −2

Original line number	Diff line number	Diff line
		@@ -6,6 +6,7 @@
		#include <linux/tick.h>
		#include <linux/mm.h>
		#include <linux/stackprotector.h>
		#include <linux/percpu.h>

		#include <asm/tlb.h>

		@@ -26,6 +27,24 @@ void cpu_idle_poll_ctrl(bool enable)
		mb();
		}

		static DEFINE_PER_CPU(int, idle_force_poll);

		void per_cpu_idle_poll_ctrl(int cpu, bool enable)
		{
		if (enable) {
		per_cpu(idle_force_poll, cpu)++;
		} else {
		per_cpu(idle_force_poll, cpu)--;
		WARN_ON_ONCE(per_cpu(idle_force_poll, cpu) < 0);
		}

		/*
		* Make sure poll mode is entered on the relevant CPU after the flag is
		* set
		*/
		mb();
		}

		#ifdef CONFIG_GENERIC_IDLE_POLL_SETUP
		static int __init cpu_idle_poll_setup(char *__unused)
		{
		@@ -47,7 +66,8 @@ static inline int cpu_idle_poll(void)
		rcu_idle_enter();
		trace_cpu_idle_rcuidle(0, smp_processor_id());
		local_irq_enable();
		while (!tif_need_resched() && cpu_idle_force_poll)
		while (!tif_need_resched() && (cpu_idle_force_poll \|\|
		__get_cpu_var(idle_force_poll)))
		cpu_relax();
		trace_cpu_idle_rcuidle(PWR_EVENT_EXIT, smp_processor_id());
		rcu_idle_exit();
		@@ -89,7 +109,9 @@ static void cpu_idle_loop(void)
		* know that the IPI is going to arrive right
		* away
		*/
		if (cpu_idle_force_poll \|\| tick_check_broadcast_expired()) {
		if (cpu_idle_force_poll \|\|
		tick_check_broadcast_expired() \|\|
		__get_cpu_var(idle_force_poll)) {
		cpu_idle_poll();
		} else {
		if (!current_clr_polling_and_test()) {
		@@ -133,5 +155,6 @@ void cpu_startup_entry(enum cpuhp_state state)
		#endif
		__current_set_polling();
		arch_cpu_idle_prepare();
		per_cpu(idle_force_poll, smp_processor_id()) = 0;
		cpu_idle_loop();
		}