Commit 165097ba authored by Xiangyou Xie's avatar Xiangyou Xie Committed by Zheng Zengkai
Browse files

cpuidle: add cpuidle-haltpoll driver module parameter 

hulk inclusion
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/I6404X?from=project-issue


CVE: NA

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

To ensure energy efficiency, haltpoll is disabled by default.
But In some performance scenarios, you can enable haltpoll using
the following methods:

echo Y > /sys/module/cpuidle_haltpoll/parameters/force

Signed-off-by: default avatarXiangyou Xie <xiexiangyou@huawei.com>
Reviewed-by: default avatarKeqian Zhu <zhukeqian1@huawei.com>
Reviewed-by: default avatarQingqing Li <liqingqing3@huawei.com>
Reviewed-by: default avatarchenhui <judy.chenhui@huawei.com>
Signed-off-by: default avatarZheng Zengkai <zhengzengkai@huawei.com>
parent 6f2a1173

drivers/cpuidle/cpuidle-haltpoll.c

+80 −17
Original line number Diff line number Diff line
@@ -18,9 +18,17 @@ 
#include <linux/kvm_para.h>

#include <linux/cpuidle_haltpoll.h>



static bool force __read_mostly;

module_param(force, bool, 0444);

MODULE_PARM_DESC(force, "Load unconditionally");

static bool force;

MODULE_PARM_DESC(force, "bool, enable haltpoll driver");

static int enable_haltpoll_driver(const char *val, const struct kernel_param *kp);

static int register_haltpoll_driver(void);

static void unregister_haltpoll_driver(void);



static const struct kernel_param_ops enable_haltpoll_ops = {

	.set = enable_haltpoll_driver,

	.get = param_get_bool,

};

module_param_cb(force, &enable_haltpoll_ops, &force, 0644);



static struct cpuidle_device __percpu *haltpoll_cpuidle_devices;

static enum cpuhp_state haltpoll_hp_state;
@@ -36,6 +44,42 @@ static int default_enter_idle(struct cpuidle_device *dev, 
	return index;

}





static int enable_haltpoll_driver(const char *val, const struct kernel_param *kp)

{

#ifdef CONFIG_ARM64

	int ret;

	bool do_enable;



	if (!val)

		return 0;



	ret = strtobool(val, &do_enable);



	if (ret || force == do_enable)

		return ret;



	if (do_enable) {

		ret = register_haltpoll_driver();



		if (!ret) {

			pr_info("Enable haltpoll driver.\n");

			force = 1;

		} else {

			pr_err("Fail to enable haltpoll driver.\n");

		}

	} else {

		unregister_haltpoll_driver();

		force = 0;

		pr_info("Unregister haltpoll driver.\n");

	}



	return ret;

#else

	return -1;

#endif

}



static struct cpuidle_driver haltpoll_driver = {

	.name = "haltpoll",

	.governor = "haltpoll",
@@ -84,22 +128,18 @@ static int haltpoll_cpu_offline(unsigned int cpu) 
	return 0;

}



static void haltpoll_uninit(void)

{

	if (haltpoll_hp_state)

		cpuhp_remove_state(haltpoll_hp_state);

	cpuidle_unregister_driver(&haltpoll_driver);



	free_percpu(haltpoll_cpuidle_devices);

	haltpoll_cpuidle_devices = NULL;

}



static bool haltpoll_want(void)

{

	return kvm_para_has_hint(KVM_HINTS_REALTIME);

}



static int __init haltpoll_init(void)

static void haltpoll_uninit(void)

{

	unregister_haltpoll_driver();

}



static int register_haltpoll_driver(void)

{

	int ret;

	struct cpuidle_driver *drv = &haltpoll_driver;
@@ -112,9 +152,6 @@ static int __init haltpoll_init(void) 


	cpuidle_poll_state_init(drv);



	if (!force && (!kvm_para_available() || !haltpoll_want()))

		return -ENODEV;



	ret = cpuidle_register_driver(drv);

	if (ret < 0)

		return ret;
@@ -137,8 +174,34 @@ static int __init haltpoll_init(void) 
	return ret;

}



static void unregister_haltpoll_driver(void)

{

	if (haltpoll_hp_state)

		cpuhp_remove_state(haltpoll_hp_state);

	cpuidle_unregister_driver(&haltpoll_driver);



	free_percpu(haltpoll_cpuidle_devices);

	haltpoll_cpuidle_devices = NULL;



}



static int __init haltpoll_init(void)

{

	int ret = 0;

#ifdef CONFIG_X86

	/* Do not load haltpoll if idle= is passed */

	if (boot_option_idle_override != IDLE_NO_OVERRIDE)

		return -ENODEV;

#endif

	if (force || (haltpoll_want() && kvm_para_available()))

		ret = register_haltpoll_driver();



	return ret;

}



static void __exit haltpoll_exit(void)

{

	if (haltpoll_cpuidle_devices)

		haltpoll_uninit();

}

drivers/cpuidle/governors/haltpoll.c

+2 −2
Original line number Diff line number Diff line
@@ -39,7 +39,7 @@ module_param(guest_halt_poll_grow_start, uint, 0644); 
static bool guest_halt_poll_allow_shrink __read_mostly = true;

module_param(guest_halt_poll_allow_shrink, bool, 0644);



static bool enable __read_mostly;

static bool enable __read_mostly = true;

module_param(enable, bool, 0444);

MODULE_PARM_DESC(enable, "Load unconditionally");
@@ -144,7 +144,7 @@ static struct cpuidle_governor haltpoll_governor = { 


static int __init init_haltpoll(void)

{

	if (kvm_para_available() || enable)

	if (enable)

		return cpuidle_register_governor(&haltpoll_governor);



	return 0;