blob: 3f86d23c592ec0cdce4b6e8019a02256f4146d78 (
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
|
/*
* poll_state.c - Polling idle state
*
* This file is released under the GPLv2.
*/
#include <linux/cpuidle.h>
#include <linux/sched.h>
#include <linux/sched/clock.h>
#include <linux/sched/idle.h>
#define POLL_IDLE_TIME_LIMIT (TICK_NSEC / 16)
#define POLL_IDLE_RELAX_COUNT 200
static int __cpuidle poll_idle(struct cpuidle_device *dev,
struct cpuidle_driver *drv, int index)
{
u64 time_start = local_clock();
local_irq_enable();
if (!current_set_polling_and_test()) {
unsigned int loop_count = 0;
while (!need_resched()) {
cpu_relax();
if (loop_count++ < POLL_IDLE_RELAX_COUNT)
continue;
loop_count = 0;
if (local_clock() - time_start > POLL_IDLE_TIME_LIMIT)
break;
}
}
current_clr_polling();
return index;
}
void cpuidle_poll_state_init(struct cpuidle_driver *drv)
{
struct cpuidle_state *state = &drv->states[0];
snprintf(state->name, CPUIDLE_NAME_LEN, "POLL");
snprintf(state->desc, CPUIDLE_DESC_LEN, "CPUIDLE CORE POLL IDLE");
state->exit_latency = 0;
state->target_residency = 0;
state->power_usage = -1;
state->enter = poll_idle;
state->disabled = false;
state->flags = CPUIDLE_FLAG_POLLING;
}
EXPORT_SYMBOL_GPL(cpuidle_poll_state_init);
|
