[PATCH v4] sched: Provide USF for the portable equipment.

From: Dongdong Yang
Date: Tue Aug 04 2020 - 03:54:12 EST


From: Dongdong Yang <yangdongdong@xxxxxxxxxx>

The power consumption and UI response are more cared for by the portable
equipment users. USF(User Sensitive Feedback factor) auxiliary cpufreq
governor is providing more utils adjustment settings to the high level
by scenario identification.

>From the view of portable equipment, screen off status usually stands
for no request from the user, however, the kernel is still expected to
notify the user in time on modem, network or powerkey events occur. In
some scenarios, such as listening to music, low power processors, such
as DSP, take more actions and CPU load requirements cut down.  It would
bring more power consumption benefit if high level have interfaces to
adjust utils according to the current scenario and load.

In addition, the portable equipment user usually heavily interact with
devices by touch, and other peripherals. The boost preemptive counts
are marking the load requirement urgent, vice versa. If such feedback
factor could be set to high level according to the scenario, it would
contribute to the power consumption and UI response.

If no USF sysfs inode is set, and no screen on or off event,
adjust_task_pred_demand shall not be invoked. Once sched_usf_up_l0_r
sched_usf_down_r or sched_usf_non_ux_r be set, adjust_task_pred_demand
shall be called back to update settings according to high level
scenario identification.

We can get about 17% mean power consumption save at listening to music
with speaker on "screen off" scenario, as below statistical data from
7766 XiaoMi devices for two weeks with sched_usf_non_ux_r be set:

day1 day2 day3 day4
count 7766.000000 7766.000000 7766.000000 7766.000000
mean 88.035525 85.500282 83.829305 86.054997
std 111.049980 108.258834 107.562583 108.558240
min 0.099000 0.037000 0.067000 0.045000
25% 34.765500 34.021750 34.101500 34.423000
50% 54.950000 55.286500 54.189500 54.248500
75% 95.954000 93.942000 91.738000 94.0592500
80% 114.675000 107.430000 106.378000 108.673000
85% 137.851000 129.511000 127.156500 131.750750
90% 179.669000 170.208500 164.027000 172.348000
95% 272.395000 257.845500 247.750500 263.275750
98% 399.034500 412.170400 391.484000 402.835600

day5 day6 day7 day8
count 7766.000000 7766.00000 7766.000000 7766.000000
mean 82.532677 79.21923 77.611380 81.075081
std 104.870079 101.34819 103.140037 97.506221
min 0.051000 0.02900 0.007000 0.068000
25% 32.873000 33.44400 31.965500 33.863500
50% 52.180500 51.56550 50.806500 53.080000
75% 90.905750 86.82625 83.859250 89.973000
80% 105.455000 99.64700 97.271000 104.225000
85% 128.300000 118.47825 116.570250 126.648250
90% 166.647500 149.18000 150.649500 161.087000
95% 247.208500 224.36050 226.380000 245.291250
98% 393.002000 347.92060 369.791800 378.778600

day9 day10 day11 day12
count 7766.000000 7766.000000 7766.000000 7766.000000
mean 79.989170 83.859417 78.032930 77.060542
std 104.226122 108.893043 102.561715 99.844276
min 0.118000 0.017000 0.028000 0.039000
25% 32.056250 33.454500 31.176250 30.897750
50% 51.506000 54.056000 48.969500 49.069000
75% 88.513500 92.953500 83.506750 84.096000
80% 102.876000 107.845000 97.717000 98.073000
85% 124.363000 128.288000 118.366500 116.869250
90% 160.557000 167.084000 154.342500 148.187500
95% 231.149000 242.925750 236.759000 228.131250
98% 367.206600 388.619100 385.269100 376.541600

day13 day14
count 7766.000000 7766.000000
mean 75.528036 73.702878
std 90.750594 86.796016
min 0.066000 0.054000
25% 31.170500 31.608500
50% 48.758500 49.215000
75% 84.522750 83.053000
80% 97.879000 94.875000
85% 116.680250 113.573750
90% 149.083500 144.089500
95% 226.177750 211.488750
98% 347.011100 331.317100

Signed-off-by: Dongdong Yang <yangdongdong@xxxxxxxxxx>
Co-developed-by: Jun Tao <taojun@xxxxxxxxxx>
Co-developed-by: Qiwu Huang <huangqiwu@xxxxxxxxxx>
Co-developed-by: Peng Wang <rocking@xxxxxxxxxxxxxxxxx>
---
Documentation/ABI/testing/sysfs-devices-system-cpu | 48 ++++
drivers/cpufreq/Kconfig | 11 +
include/trace/events/sched.h | 35 +++
kernel/sched/Makefile | 1 +
kernel/sched/cpufreq_schedutil.c | 3 +
kernel/sched/sched.h | 10 +
kernel/sched/usf.c | 294 +++++++++++++++++++++
7 files changed, 402 insertions(+)
create mode 100644 kernel/sched/usf.c

diff --git a/Documentation/ABI/testing/sysfs-devices-system-cpu b/Documentation/ABI/testing/sysfs-devices-system-cpu
index b555df8..e299418 100644
--- a/Documentation/ABI/testing/sysfs-devices-system-cpu
+++ b/Documentation/ABI/testing/sysfs-devices-system-cpu
@@ -614,3 +614,51 @@ Description: SPURR ticks for cpuX when it was idle.

This sysfs interface exposes the number of SPURR ticks
for cpuX when it was idle.
+
+What: /sys/devices/system/cpu/sched_usf
+ /sys/devices/system/cpu/sched_usf/sched_usf_non_ux_r
+ /sys/devices/system/cpu/sched_usf/sched_usf_up_l0_r
+ /sys/devices/system/cpu/sched_usf/sched_usf_down_r
+Date: Aug 2020
+Contact: Linux kernel mailing list <linux-kernel@xxxxxxxxxxxxxxx>
+Description: User Sensitive Feedback factor auxiliary scheduling which
+ is providing more utils adjustment settings to the high level
+ by scenario identification.
+ sched_usf_non_ux_r:
+ The ratio of utils is cut down on screen off. The
+ default value is 0, which no util is adjusted on sugov
+ calculating utils to select cpufreq. Its range is
+ [-100 , 0]. If its value falls into [-50, 0), the half
+ of utils, which calculates cpufreq, shall be cut down.
+ If its value falls into [-100, -50), only a quarter of
+ utils are left to continue to calculate cpufreq.
+ It is expected to be set [-100, 0) once enter into the
+ identificated scenario, such as listen to music on
+ screen off, and recover to 0 on out of the scenario,
+ such as screen on.
+
+ sched_usf_up_l0_r:
+ The ratio of utils is boost up on screen on. The
+ default value is 0, which no util is adjusted on sugov
+ calculates utils to select cpufreq. Its range is [0 , 100].
+ If its value falls into (0, 50], a quarter of extra utils,
+ which calculate cpufreq, shall be added. If its value
+ falls into (50, 100], the half of extra utils are added
+ to continue to calculate cpufreq.
+ It is expected to be set (0, 100] once enter into the
+ identificated scenario, such as browsing videolet on
+ screen on, and recover to 0 on out of the scenario,
+ such as screen off or videolet into background.
+
+ sched_usf_down_r:
+ The ratio of utils is cut down on screen on. The
+ default value is 0, which no util is adjusted on sugov
+ calculating utils to select cpufreq. Its range is
+ [-100 , 0]. If its value falls into [-50, 0), the half
+ of utils, which calculate cpufreq, shall be cut down.
+ If its value falls into [-100, -50), only a quarter of
+ utils are left to continue to calculate cpufreq.
+ It is expected to be set [-100, 0) once enter into the
+ identificated scenario, such as browsing videolet on
+ screen on, and recover to 0 on out of the scenario,
+ such as screen off or vidolet into background.
diff --git a/drivers/cpufreq/Kconfig b/drivers/cpufreq/Kconfig
index e917501..a21c6ad 100644
--- a/drivers/cpufreq/Kconfig
+++ b/drivers/cpufreq/Kconfig
@@ -224,6 +224,17 @@ config CPUFREQ_DT_PLATDEV

If in doubt, say N.

+config SCHED_USF
+ bool "User Sensitive Factors for Scheduler"
+ depends on CPU_FREQ_GOV_SCHEDUTIL && FB
+ help
+ Select this option to enable the adjustment on the cpufreq with
+ the user sensitive factors on schedule. It is special for mobile
+ devices which more power care and quick response requirement on
+ screen on.
+
+ If unsure, say N.
+
if X86
source "drivers/cpufreq/Kconfig.x86"
endif
diff --git a/include/trace/events/sched.h b/include/trace/events/sched.h
index ed168b0..d5e20b7 100644
--- a/include/trace/events/sched.h
+++ b/include/trace/events/sched.h
@@ -488,6 +488,41 @@ TRACE_EVENT(sched_process_hang,
#endif /* CONFIG_DETECT_HUNG_TASK */

/*
+ * Tracepoint for tracking tuils be adjusted by USF:
+ */
+#ifdef CONFIG_SCHED_USF
+TRACE_EVENT(sched_usf_adjust_utils,
+
+ TP_PROTO(int cpu_id, int up, int down, int nonux, unsigned long utils),
+
+ TP_ARGS(cpu_id, up, down, nonux, utils),
+
+ TP_STRUCT__entry(
+ __field(int, cpu_id)
+ __field(int, up)
+ __field(int, down)
+ __field(int, nonux)
+ __field(unsigned long, utils)
+ ),
+
+ TP_fast_assign(
+ __entry->cpu_id = cpu_id;
+ __entry->up = up;
+ __entry->down = down;
+ __entry->nonux = nonux;
+ __entry->utils = utils;
+ ),
+
+ TP_printk("cpu_id=%d up=%d down=%d nonux=%d utils=%lu",
+ __entry->cpu_id,
+ __entry->up,
+ __entry->down,
+ __entry->nonux,
+ __entry->utils)
+);
+#endif /* CONFIG_SCHED_USF */
+
+/*
* Tracks migration of tasks from one runqueue to another. Can be used to
* detect if automatic NUMA balancing is bouncing between nodes.
*/
diff --git a/kernel/sched/Makefile b/kernel/sched/Makefile
index 5fc9c9b..58a0e7b 100644
--- a/kernel/sched/Makefile
+++ b/kernel/sched/Makefile
@@ -36,3 +36,4 @@ obj-$(CONFIG_CPU_FREQ_GOV_SCHEDUTIL) += cpufreq_schedutil.o
obj-$(CONFIG_MEMBARRIER) += membarrier.o
obj-$(CONFIG_CPU_ISOLATION) += isolation.o
obj-$(CONFIG_PSI) += psi.o
+obj-$(CONFIG_SCHED_USF) += usf.o
diff --git a/kernel/sched/cpufreq_schedutil.c b/kernel/sched/cpufreq_schedutil.c
index 7fbaee2..79a0040 100644
--- a/kernel/sched/cpufreq_schedutil.c
+++ b/kernel/sched/cpufreq_schedutil.c
@@ -289,12 +289,15 @@ unsigned long schedutil_cpu_util(int cpu, unsigned long util_cfs,
return min(max, util);
}

+DEFINE_STATIC_KEY_FALSE(adjust_task_pred_set);
static unsigned long sugov_get_util(struct sugov_cpu *sg_cpu)
{
struct rq *rq = cpu_rq(sg_cpu->cpu);
unsigned long util = cpu_util_cfs(rq);
unsigned long max = arch_scale_cpu_capacity(sg_cpu->cpu);

+ if (static_branch_unlikely(&adjust_task_pred_set))
+ adjust_task_pred_demand(sg_cpu->cpu, &util, rq);
sg_cpu->max = max;
sg_cpu->bw_dl = cpu_bw_dl(rq);

diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h
index 877fb08..496130b 100644
--- a/kernel/sched/sched.h
+++ b/kernel/sched/sched.h
@@ -2540,5 +2540,15 @@ static inline bool is_per_cpu_kthread(struct task_struct *p)
}
#endif

+DECLARE_STATIC_KEY_FALSE(adjust_task_pred_set);
+#ifdef CONFIG_SCHED_USF
+void adjust_task_pred_demand(int cpuid, unsigned long *util,
+ struct rq *rq);
+#else
+static inline void adjust_task_pred_demand(int cpuid,
+ unsigned long *util, struct rq *rq)
+{ }
+#endif
+
void swake_up_all_locked(struct swait_queue_head *q);
void __prepare_to_swait(struct swait_queue_head *q, struct swait_queue *wait);
diff --git a/kernel/sched/usf.c b/kernel/sched/usf.c
new file mode 100644
index 0000000..d4d7998
--- /dev/null
+++ b/kernel/sched/usf.c
@@ -0,0 +1,294 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2020 XiaoMi Inc.
+ * Author: Yang Dongdong <yangdongdong@xxxxxxxxxx>
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+ * See http://www.gnu.org/licenses/gpl-2.0.html for more details.
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/platform_device.h>
+#include <linux/kthread.h>
+#include <linux/cpu.h>
+#include <linux/sysfs.h>
+#include <linux/kthread.h>
+#include <linux/kobject.h>
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/kallsyms.h>
+#include <linux/fb.h>
+#include <linux/notifier.h>
+#include <trace/events/sched.h>
+#include "sched.h"
+
+#define BOOST_MIN_V -100
+#define BOOST_MAX_V 100
+#define LEVEL_TOP 3
+
+#define USF_TAG "[usf_sched]"
+
+DEFINE_PER_CPU(unsigned long[PID_MAX_DEFAULT], task_hist_nivcsw);
+
+static struct {
+ bool is_sched_usf_enabled;
+ bool is_screen_on;
+ int sysctl_sched_usf_up_l0;
+ int sysctl_sched_usf_down;
+ int sysctl_sched_usf_non_ux;
+ int usf_up_l0;
+ int usf_down;
+ int usf_non_ux;
+} usf_vdev;
+
+void adjust_task_pred_demand(int cpuid,
+ unsigned long *util,
+ struct rq *rq)
+{
+ /* sysctl_sched_latency/sysctl_sched_min_granularity */
+ u32 bl_sw_num = 3;
+
+ if (!usf_vdev.is_sched_usf_enabled || !rq || !rq->curr ||
+ (rq->curr->pid >= PID_MAX_DEFAULT))
+ return;
+
+ if (usf_vdev.is_screen_on) {
+ if (rq->curr->nivcsw >
+ (per_cpu(task_hist_nivcsw, cpuid)[rq->curr->pid]
+ + bl_sw_num + 1)) {
+ (*util) += (*util) >> usf_vdev.usf_up_l0;
+ } else if (rq->curr->nivcsw <
+ (per_cpu(task_hist_nivcsw, cpuid)[rq->curr->pid]
+ + bl_sw_num - 1) && (rq->nr_running < bl_sw_num)) {
+ (*util) >>= usf_vdev.usf_down;
+ }
+ per_cpu(task_hist_nivcsw, cpuid)[rq->curr->pid] =
+ rq->curr->nivcsw;
+ } else if (rq->curr->mm) {
+ (*util) >>= usf_vdev.usf_non_ux;
+ }
+
+ trace_sched_usf_adjust_utils(cpuid, usf_vdev.usf_up_l0,
+ usf_vdev.usf_down,
+ usf_vdev.usf_non_ux, *util);
+}
+
+static int usf_lcd_notifier(struct notifier_block *nb,
+ unsigned long val, void *data)
+{
+ struct fb_event *evdata = data;
+ unsigned int blank;
+
+ if (!evdata)
+ return 0;
+
+ if (val != FB_EVENT_BLANK)
+ return 0;
+
+ if (evdata->data && val == FB_EVENT_BLANK) {
+ blank = *(int *)(evdata->data);
+
+ switch (blank) {
+ case FB_BLANK_POWERDOWN:
+ usf_vdev.is_screen_on = false;
+ if (usf_vdev.sysctl_sched_usf_non_ux != 0)
+ static_branch_enable(&adjust_task_pred_set);
+ else
+ static_branch_disable(&adjust_task_pred_set);
+
+ break;
+
+ case FB_BLANK_UNBLANK:
+ usf_vdev.is_screen_on = true;
+ if (usf_vdev.sysctl_sched_usf_up_l0 != 0 ||
+ usf_vdev.sysctl_sched_usf_down != 0)
+ static_branch_enable(&adjust_task_pred_set);
+ else
+ static_branch_disable(&adjust_task_pred_set);
+ break;
+ default:
+ break;
+ }
+
+ usf_vdev.is_sched_usf_enabled = true;
+ pr_info("%s : usf_vdev.is_screen_on:%b\n",
+ __func__, usf_vdev.is_screen_on);
+ }
+ return NOTIFY_OK;
+}
+
+static struct notifier_block usf_lcd_nb = {
+ .notifier_call = usf_lcd_notifier,
+ .priority = INT_MAX,
+};
+
+static ssize_t store_sched_usf_up_l0_r(struct kobject *kobj,
+ struct kobj_attribute *attr,
+ const char *buf, size_t count)
+{
+ int val = 0;
+ int ret = 0;
+
+ ret = kstrtoint(buf, 0, &val);
+ if (ret)
+ return ret;
+
+ if (val == 0) {
+ usf_vdev.sysctl_sched_usf_up_l0 = val;
+ usf_vdev.usf_up_l0 = 0;
+ } else if ((val > 0) && (val <= BOOST_MAX_V)) {
+ usf_vdev.sysctl_sched_usf_up_l0 = val;
+ usf_vdev.usf_up_l0 = LEVEL_TOP -
+ DIV_ROUND_UP(val, BOOST_MAX_V / 2);
+ ret = count;
+ } else {
+ pr_err(USF_TAG "%d should fall into [%d %d]",
+ val, 0, BOOST_MAX_V);
+ ret = -EINVAL;
+ }
+ if ((usf_vdev.sysctl_sched_usf_up_l0 == 0) &&
+ (usf_vdev.sysctl_sched_usf_down == 0))
+ static_branch_disable(&adjust_task_pred_set);
+ else
+ static_branch_enable(&adjust_task_pred_set);
+
+ return ret;
+}
+
+static ssize_t store_sched_usf_down_r(struct kobject *kobj,
+ struct kobj_attribute *attr,
+ const char *buf, size_t count)
+{
+ int val = 0;
+ int ret = 0;
+
+ ret = kstrtoint(buf, 0, &val);
+ if (ret)
+ return ret;
+
+ if ((val >= BOOST_MIN_V) && (val <= 0)) {
+ usf_vdev.sysctl_sched_usf_down = val;
+ usf_vdev.usf_down = DIV_ROUND_UP(-val, -BOOST_MIN_V / 2);
+ ret = count;
+ } else {
+ pr_err(USF_TAG "%d should fall into [%d %d]",
+ val, BOOST_MIN_V, 0);
+ ret = -EINVAL;
+ }
+ if ((usf_vdev.sysctl_sched_usf_up_l0 == 0) &&
+ (usf_vdev.sysctl_sched_usf_down == 0))
+ static_branch_disable(&adjust_task_pred_set);
+ else
+ static_branch_enable(&adjust_task_pred_set);
+
+ return ret;
+}
+
+static ssize_t store_sched_usf_non_ux_r(struct kobject *kobj,
+ struct kobj_attribute *attr,
+ const char *buf, size_t count)
+{
+ int val = 0;
+ int ret = 0;
+
+ ret = kstrtoint(buf, 0, &val);
+ if (ret)
+ return ret;
+
+ if ((val >= BOOST_MIN_V) && (val <= 0)) {
+ usf_vdev.sysctl_sched_usf_non_ux = val;
+ usf_vdev.usf_non_ux = DIV_ROUND_UP(-val, -BOOST_MIN_V / 2);
+ ret = count;
+ } else {
+ pr_err(USF_TAG "%d should fall into [%d %d]",
+ val, BOOST_MIN_V, 0);
+ ret = -EINVAL;
+ }
+ if (usf_vdev.sysctl_sched_usf_non_ux == 0)
+ static_branch_disable(&adjust_task_pred_set);
+ else
+ static_branch_enable(&adjust_task_pred_set);
+
+ return ret;
+}
+
+#define usf_attr_rw(_name) \
+static struct kobj_attribute _name = \
+__ATTR(_name, 0664, show_##_name, store_##_name)
+
+#define usf_show_node(_name, _value) \
+static ssize_t show_##_name \
+(struct kobject *kobj, struct kobj_attribute *attr, char *buf) \
+{ \
+ return sprintf(buf, "%d", usf_vdev.sysctl_##_value); \
+}
+
+usf_show_node(sched_usf_up_l0_r, sched_usf_up_l0);
+usf_show_node(sched_usf_down_r, sched_usf_down);
+usf_show_node(sched_usf_non_ux_r, sched_usf_non_ux);
+
+usf_attr_rw(sched_usf_up_l0_r);
+usf_attr_rw(sched_usf_down_r);
+usf_attr_rw(sched_usf_non_ux_r);
+
+static struct attribute *sched_attrs[] = {
+ &sched_usf_up_l0_r.attr,
+ &sched_usf_down_r.attr,
+ &sched_usf_non_ux_r.attr,
+ NULL,
+};
+
+static struct attribute_group sched_attr_group = {
+ .attrs = sched_attrs,
+};
+
+static int __init intera_monitor_init(void)
+{
+ int res = -1;
+ struct device *dev;
+
+ res = fb_register_client(&usf_lcd_nb);
+ if (res < 0) {
+ pr_err("Failed to register usf_lcd_nb!\n");
+ return res;
+ }
+
+ /*
+ * create a sched_usf in cpu_subsys:
+ * /sys/devices/system/cpu/sched_usf/...
+ */
+ dev = cpu_subsys.dev_root;
+ res = sysfs_create_group(&dev->kobj, &sched_attr_group);
+ if (res) {
+ fb_unregister_client(&usf_lcd_nb);
+ return res;
+ }
+ static_branch_disable(&adjust_task_pred_set);
+
+ return res;
+}
+
+module_init(intera_monitor_init);
+
+static void __exit intera_monitor_exit(void)
+{
+ struct device *dev;
+
+ dev = cpu_subsys.dev_root;
+ sysfs_remove_group(&dev->kobj, &sched_attr_group);
+ fb_unregister_client(&usf_lcd_nb);
+ static_branch_disable(&adjust_task_pred_set);
+}
+
+module_exit(intera_monitor_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("XiaoMi USF SCHED");
+MODULE_AUTHOR("Yang Dongdong <yangdongdong@xxxxxxxxxx>");
--
2.7.4