add new system file

hc

2024-02-20 102a0743326a03cd1a1202ceda21e175b7d3575c

 kernel/kernel/time/tick-common.c
..
..
@@ -1,15 +1,11 @@
1
+// SPDX-License-Identifier: GPL-2.0
1
2
 /*
2
- * linux/kernel/time/tick-common.c
3
- *
4
3
  * This file contains the base functions to manage periodic tick
5
4
  * related events.
6
5
  *
7
6
  * Copyright(C) 2005-2006, Thomas Gleixner <tglx@linutronix.de>
8
7
  * Copyright(C) 2005-2007, Red Hat, Inc., Ingo Molnar
9
8
  * Copyright(C) 2006-2007, Timesys Corp., Thomas Gleixner
10
- *
11
- * This code is licenced under the GPL version 2. For details see
12
- * kernel-base/COPYING.
13
9
  */
14
10
 #include <linux/cpu.h>
15
11
 #include <linux/err.h>
..
..
@@ -21,6 +17,7 @@
21
17
 #include <linux/sched.h>
22
18
 #include <linux/module.h>
23
19
 #include <trace/events/power.h>
20
+#include <trace/hooks/sched.h>
24
21
 
25
22
 #include <asm/irq_regs.h>
26
23
 
..
..
@@ -34,7 +31,6 @@
34
31
  * Tick next event: keeps track of the tick time
35
32
  */
36
33
 ktime_t tick_next_period;
37
-ktime_t tick_period;
38
34
 
39
35
 /*
40
36
  * tick_do_timer_cpu is a timer core internal variable which holds the CPU NR
..
..
@@ -51,6 +47,14 @@
51
47
  *    procedure also covers cpu hotplug.
52
48
  */
53
49
 int tick_do_timer_cpu __read_mostly = TICK_DO_TIMER_BOOT;
50
+#ifdef CONFIG_NO_HZ_FULL
51
+/*
52
+ * tick_do_timer_boot_cpu indicates the boot CPU temporarily owns
53
+ * tick_do_timer_cpu and it should be taken over by an eligible secondary
54
+ * when one comes online.
55
+ */
56
+static int tick_do_timer_boot_cpu __read_mostly = -1;
57
+#endif
54
58
 
55
59
 /*
56
60
  * Debugging: see timer_list.c
..
..
@@ -80,14 +84,17 @@
80
84
 static void tick_periodic(int cpu)
81
85
 {
82
86
 	if (tick_do_timer_cpu == cpu) {
83
-		write_seqlock(&jiffies_lock);
87
+		raw_spin_lock(&jiffies_lock);
88
+		write_seqcount_begin(&jiffies_seq);
84
89
 
85
90
 		/* Keep track of the next tick event */
86
-		tick_next_period = ktime_add(tick_next_period, tick_period);
91
+		tick_next_period = ktime_add_ns(tick_next_period, TICK_NSEC);
87
92
 
88
93
 		do_timer(1);
89
-		write_sequnlock(&jiffies_lock);
94
+		write_seqcount_end(&jiffies_seq);
95
+		raw_spin_unlock(&jiffies_lock);
90
96
 		update_wall_time();
97
+		trace_android_vh_jiffies_update(NULL);
91
98
 	}
92
99
 
93
100
 	update_process_times(user_mode(get_irq_regs()));
..
..
@@ -121,7 +128,7 @@
121
128
 		 * Setup the next period for devices, which do not have
122
129
 		 * periodic mode:
123
130
 		 */
124
-		next = ktime_add(next, tick_period);
131
+		next = ktime_add_ns(next, TICK_NSEC);
125
132
 
126
133
 		if (!clockevents_program_event(dev, next, false))
127
134
 			return;
..
..
@@ -154,23 +161,43 @@
154
161
 	    !tick_broadcast_oneshot_active()) {
155
162
 		clockevents_switch_state(dev, CLOCK_EVT_STATE_PERIODIC);
156
163
 	} else {
157
-		unsigned long seq;
164
+		unsigned int seq;
158
165
 		ktime_t next;
159
166
 
160
167
 		do {
161
-			seq = read_seqbegin(&jiffies_lock);
168
+			seq = read_seqcount_begin(&jiffies_seq);
162
169
 			next = tick_next_period;
163
-		} while (read_seqretry(&jiffies_lock, seq));
170
+		} while (read_seqcount_retry(&jiffies_seq, seq));
164
171
 
165
172
 		clockevents_switch_state(dev, CLOCK_EVT_STATE_ONESHOT);
166
173
 
167
174
 		for (;;) {
168
175
 			if (!clockevents_program_event(dev, next, false))
169
176
 				return;
170
-			next = ktime_add(next, tick_period);
177
+			next = ktime_add_ns(next, TICK_NSEC);
171
178
 		}
172
179
 	}
173
180
 }
181
+
182
+#ifdef CONFIG_NO_HZ_FULL
183
+static void giveup_do_timer(void *info)
184
+{
185
+	int cpu = *(unsigned int *)info;
186
+
187
+	WARN_ON(tick_do_timer_cpu != smp_processor_id());
188
+
189
+	tick_do_timer_cpu = cpu;
190
+}
191
+
192
+static void tick_take_do_timer_from_boot(void)
193
+{
194
+	int cpu = smp_processor_id();
195
+	int from = tick_do_timer_boot_cpu;
196
+
197
+	if (from >= 0 && from != cpu)
198
+		smp_call_function_single(from, giveup_do_timer, &cpu, 1);
199
+}
200
+#endif
174
201
 
175
202
 /*
176
203
  * Setup the tick device
..
..
@@ -191,12 +218,24 @@
191
218
 		 * this cpu:
192
219
 		 */
193
220
 		if (tick_do_timer_cpu == TICK_DO_TIMER_BOOT) {
194
-			if (!tick_nohz_full_cpu(cpu))
195
-				tick_do_timer_cpu = cpu;
196
-			else
197
-				tick_do_timer_cpu = TICK_DO_TIMER_NONE;
221
+			tick_do_timer_cpu = cpu;
198
222
 			tick_next_period = ktime_get();
199
-			tick_period = NSEC_PER_SEC / HZ;
223
+#ifdef CONFIG_NO_HZ_FULL
224
+			/*
225
+			 * The boot CPU may be nohz_full, in which case set
226
+			 * tick_do_timer_boot_cpu so the first housekeeping
227
+			 * secondary that comes up will take do_timer from
228
+			 * us.
229
+			 */
230
+			if (tick_nohz_full_cpu(cpu))
231
+				tick_do_timer_boot_cpu = cpu;
232
+
233
+		} else if (tick_do_timer_boot_cpu != -1 &&
234
+						!tick_nohz_full_cpu(cpu)) {
235
+			tick_take_do_timer_from_boot();
236
+			tick_do_timer_boot_cpu = -1;
237
+			WARN_ON(tick_do_timer_cpu != cpu);
238
+#endif
200
239
 		}
201
240
 
202
241
 		/*
..
..
@@ -338,7 +377,7 @@
338
377
 	/*
339
378
 	 * Can the new device be used as a broadcast device ?
340
379
 	 */
341
-	tick_install_broadcast_device(newdev);
380
+	tick_install_broadcast_device(newdev, cpu);
342
381
 }
343
382
 
344
383
 /**