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