Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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kernel
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linux
1#ifndef __LINUX_PREEMPT_H
2#define __LINUX_PREEMPT_H
3
4/*
5 * include/linux/preempt.h - macros for accessing and manipulating
6 * preempt_count (used for kernel preemption, interrupt count, etc.)
7 */
8
9#include <linux/config.h>
10#include <linux/thread_info.h>
11#include <linux/linkage.h>
12
13#ifdef CONFIG_DEBUG_PREEMPT
14 extern void fastcall add_preempt_count(int val);
15 extern void fastcall sub_preempt_count(int val);
16#else
17# define add_preempt_count(val) do { preempt_count() += (val); } while (0)
18# define sub_preempt_count(val) do { preempt_count() -= (val); } while (0)
19#endif
20
21#define inc_preempt_count() add_preempt_count(1)
22#define dec_preempt_count() sub_preempt_count(1)
23
24#define preempt_count() (current_thread_info()->preempt_count)
25
26#ifdef CONFIG_PREEMPT
27
28asmlinkage void preempt_schedule(void);
29
30#define preempt_disable() \
31do { \
32 inc_preempt_count(); \
33 barrier(); \
34} while (0)
35
36#define preempt_enable_no_resched() \
37do { \
38 barrier(); \
39 dec_preempt_count(); \
40} while (0)
41
42#define preempt_check_resched() \
43do { \
44 if (unlikely(test_thread_flag(TIF_NEED_RESCHED))) \
45 preempt_schedule(); \
46} while (0)
47
48#define preempt_enable() \
49do { \
50 preempt_enable_no_resched(); \
51 barrier(); \
52 preempt_check_resched(); \
53} while (0)
54
55#else
56
57#define preempt_disable() do { } while (0)
58#define preempt_enable_no_resched() do { } while (0)
59#define preempt_enable() do { } while (0)
60#define preempt_check_resched() do { } while (0)
61
62#endif
63
64#endif /* __LINUX_PREEMPT_H */