Commit 079c60bc authored by Yu Jiahua's avatar Yu Jiahua Committed by Zheng Zengkai
Browse files

Revert "sched/idle: introduce smart halt polling" 

hulk inclusion
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/I4QU5Z?from=project-issue


CVE: NA

--------------------------------

This patch revert ias feature from open-euler kernel.

This reverts commit 1bbe05d2.

Signed-off-by: default avatarYu Jiahua <Yujiahua1@huawei.com>
Reviewed-by: default avatarChen Hui <judy.chenhui@huawei.com>
Signed-off-by: default avatarZheng Zengkai <zhengzengkai@huawei.com>
parent 1def54a7

include/linux/kernel.h

+0 −2
Original line number Diff line number Diff line
@@ -557,8 +557,6 @@ extern int sysctl_panic_on_rcu_stall; 
extern int sysctl_panic_on_stackoverflow;



extern bool crash_kexec_post_notifiers;

extern unsigned long poll_threshold_ns;





/*

 * panic_cpu is used for synchronizing panic() and crash_kexec() execution. It

kernel/sched/idle.c

+1 −29
Original line number Diff line number Diff line
@@ -13,12 +13,6 @@ 
/* Linker adds these: start and end of __cpuidle functions */

extern char __cpuidle_text_start[], __cpuidle_text_end[];



/*

 * Poll_threshold_ns indicates the maximum polling time before

 * entering real idle.

 */

unsigned long poll_threshold_ns;



/**

 * sched_idle_set_state - Record idle state for the current CPU.

 * @idle_state: State to record.
@@ -58,31 +52,12 @@ static int __init cpu_idle_nopoll_setup(char *__unused) 
__setup("hlt", cpu_idle_nopoll_setup);

#endif



static void smart_idle_poll(void)

{

	unsigned long poll_duration = poll_threshold_ns;

	ktime_t cur, stop;



	if (!poll_duration)

		return;



	stop = ktime_add_ns(ktime_get(), poll_duration);



	do {

		cpu_relax();

		if (tif_need_resched())

			break;

		cur = ktime_get();

	} while (ktime_before(cur, stop));

}



static noinline int __cpuidle cpu_idle_poll(void)

{

	trace_cpu_idle(0, smp_processor_id());

	stop_critical_timings();

	rcu_idle_enter();

	local_irq_enable();

	smart_idle_poll();



	while (!tif_need_resched() &&

	       (cpu_idle_force_poll || tick_check_broadcast_expired()))
@@ -286,7 +261,6 @@ static void cpuidle_idle_call(void) 
static void do_idle(void)

{

	int cpu = smp_processor_id();

	unsigned long idle_poll_flag = poll_threshold_ns;

	/*

	 * If the arch has a polling bit, we maintain an invariant:

	 *
@@ -319,11 +293,9 @@ static void do_idle(void) 
		 * broadcast device expired for us, we don't want to go deep

		 * idle as we know that the IPI is going to arrive right away.

		 */

		if (cpu_idle_force_poll || tick_check_broadcast_expired() ||

			  idle_poll_flag) {

		if (cpu_idle_force_poll || tick_check_broadcast_expired()) {

			tick_nohz_idle_restart_tick();

			cpu_idle_poll();

			idle_poll_flag = 0;

		} else {

			cpuidle_idle_call();

		}

kernel/sysctl.c

+0 −7
Original line number Diff line number Diff line
@@ -1858,13 +1858,6 @@ static struct ctl_table kern_table[] = { 
		.proc_handler	= sysctl_sched_uclamp_handler,

	},

#endif

	{

		.procname	= "halt_poll_threshold",

		.data		= &poll_threshold_ns,

		.maxlen		= sizeof(unsigned long),

		.mode		= 0644,

		.proc_handler	= proc_doulongvec_minmax,

	},

#ifdef CONFIG_SCHED_AUTOGROUP

	{

		.procname	= "sched_autogroup_enabled",