summaryrefslogtreecommitdiff
path: root/packages/sys-kernel/linux-image-redcore-lts/files/0011-Make-hrtimer-granularity-and-minimum-hrtimeout-confi.patch
blob: 5ac20300f5f17c8223aaa8a9387e2b3fc8c454fa (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
diff -Nur a/kernel/sysctl.c b/kernel/sysctl.c
--- a/kernel/sysctl.c	2018-11-03 17:03:07.433069521 +0000
+++ b/kernel/sysctl.c	2018-11-03 17:02:11.020267246 +0000
@@ -141,7 +141,9 @@
 extern int sched_iso_cpu;
 extern int sched_yield_type;
 #endif
-#ifdef CONFIG_PRINTK
+extern int hrtimer_granularity_us;
+extern int hrtimeout_min_us;
+#if defined(CONFIG_PRINTK) || defined(CONFIG_SCHED_MUQSS)
 static int ten_thousand __read_only = 10000;
 #endif
 #ifdef CONFIG_PERF_EVENTS
@@ -1119,6 +1121,24 @@
 		.extra2		= &two,
 	},
 #endif
+	{
+		.procname	= "hrtimer_granularity_us",
+		.data		= &hrtimer_granularity_us,
+		.maxlen		= sizeof(int),
+		.mode		= 0644,
+		.proc_handler	= &proc_dointvec_minmax,
+		.extra1		= &one,
+		.extra2		= &ten_thousand,
+	},
+	{
+		.procname	= "hrtimeout_min_us",
+		.data		= &hrtimeout_min_us,
+		.maxlen		= sizeof(int),
+		.mode		= 0644,
+		.proc_handler	= &proc_dointvec_minmax,
+		.extra1		= &one,
+		.extra2		= &ten_thousand,
+	},
 #if defined(CONFIG_S390) && defined(CONFIG_SMP)
 	{
 		.procname	= "spin_retry",
diff -Nur a/kernel/time/clockevents.c b/kernel/time/clockevents.c
--- a/kernel/time/clockevents.c	2018-11-03 17:03:07.433069521 +0000
+++ b/kernel/time/clockevents.c	2018-11-03 16:58:17.283800909 +0000
@@ -198,13 +198,9 @@
 
 #ifdef CONFIG_GENERIC_CLOCKEVENTS_MIN_ADJUST
 
-#ifdef CONFIG_SCHED_MUQSS
+int __read_mostly hrtimer_granularity_us = 100;
 /* Limit min_delta to 100us */
-#define MIN_DELTA_LIMIT		(NSEC_PER_SEC / 10000)
-#else
-/* Limit min_delta to a jiffie */
-#define MIN_DELTA_LIMIT		(NSEC_PER_SEC / HZ)
-#endif
+#define MIN_DELTA_LIMIT		(hrtimer_granularity_us * NSEC_PER_USEC)
 
 /**
  * clockevents_increase_min_delta - raise minimum delta of a clock event device
diff -Nur a/kernel/time/hrtimer.c b/kernel/time/hrtimer.c
--- a/kernel/time/hrtimer.c	2018-11-03 17:04:16.448274547 +0000
+++ b/kernel/time/hrtimer.c	2018-11-03 16:58:17.283800909 +0000
@@ -1803,7 +1803,7 @@
 long __sched schedule_msec_hrtimeout(long timeout)
 {
 	struct hrtimer_sleeper t;
-	int delta, secs, jiffs;
+	int delta, jiffs;
 	ktime_t expires;
 
 	if (!timeout) {
@@ -1820,9 +1820,8 @@
 	if (jiffs > 4 || hrtimer_resolution >= NSEC_PER_SEC / HZ || pm_freezing)
 		return schedule_timeout(jiffs);
 
-	secs = timeout / 1000;
 	delta = (timeout % 1000) * NSEC_PER_MSEC;
-	expires = ktime_set(secs, delta);
+	expires = ktime_set(0, delta);
 
 	hrtimer_init_on_stack(&t.timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
 	hrtimer_set_expires_range_ns(&t.timer, expires, delta);
@@ -1846,9 +1845,53 @@
 
 EXPORT_SYMBOL(schedule_msec_hrtimeout);
 
+#define USECS_PER_SEC 1000000
+extern int hrtimer_granularity_us;
+
+static inline long schedule_usec_hrtimeout(long timeout)
+{
+	struct hrtimer_sleeper t;
+	ktime_t expires;
+	int delta;
+
+	if (!timeout) {
+		__set_current_state(TASK_RUNNING);
+		return 0;
+	}
+
+	if (hrtimer_resolution >= NSEC_PER_SEC / HZ)
+		return schedule_timeout(usecs_to_jiffies(timeout));
+
+	if (timeout < hrtimer_granularity_us)
+		timeout = hrtimer_granularity_us;
+	delta = (timeout % USECS_PER_SEC) * NSEC_PER_USEC;
+	expires = ktime_set(0, delta);
+
+	hrtimer_init_on_stack(&t.timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
+	hrtimer_set_expires_range_ns(&t.timer, expires, delta);
+
+	hrtimer_init_sleeper(&t, current);
+
+	hrtimer_start_expires(&t.timer, HRTIMER_MODE_REL);
+
+	if (likely(t.task))
+		schedule();
+
+	hrtimer_cancel(&t.timer);
+	destroy_hrtimer_on_stack(&t.timer);
+
+	__set_current_state(TASK_RUNNING);
+
+	expires = hrtimer_expires_remaining(&t.timer);
+	timeout = ktime_to_us(expires);
+	return timeout < 0 ? 0 : timeout;
+}
+
+int __read_mostly hrtimeout_min_us = 1000;
+
 long __sched schedule_min_hrtimeout(void)
 {
-	return schedule_msec_hrtimeout(1);
+	return usecs_to_jiffies(schedule_usec_hrtimeout(hrtimeout_min_us));
 }
 
 EXPORT_SYMBOL(schedule_min_hrtimeout);