include/asm-i386/irqflags.h

   1 /*
   2  * include/asm-i386/irqflags.h
   3  *
   4  * IRQ flags handling
   5  *
   6  * This file gets included from lowlevel asm headers too, to provide
   7  * wrapped versions of the local_irq_*() APIs, based on the
   8  * raw_local_irq_*() functions from the lowlevel headers.
   9  */
  10 #ifndef _ASM_IRQFLAGS_H
  11 #define _ASM_IRQFLAGS_H
  12
  13 #ifndef __ASSEMBLY__
  14
  15 static inline unsigned long __raw_local_save_flags(void)
  16 {
  17         unsigned long flags;
  18
  19         __asm__ __volatile__(
  20                 "pushfl ; popl %0"
  21                 : "=g" (flags)
  22                 : /* no input */
  23         );
  24
  25         return flags;
  26 }
  27
  28 #define raw_local_save_flags(flags) \
  29                 do { (flags) = __raw_local_save_flags(); } while (0)
  30
  31 static inline void raw_local_irq_restore(unsigned long flags)
  32 {
  33         __asm__ __volatile__(
  34                 "pushl %0 ; popfl"
  35                 : /* no output */
  36                 :"g" (flags)
  37                 :"memory", "cc"
  38         );
  39 }
  40
  41 static inline void raw_local_irq_disable(void)
  42 {
  43         __asm__ __volatile__("cli" : : : "memory");
  44 }
  45
  46 static inline void raw_local_irq_enable(void)
  47 {
  48         __asm__ __volatile__("sti" : : : "memory");
  49 }
  50
  51 /*
  52  * Used in the idle loop; sti takes one instruction cycle
  53  * to complete:
  54  */
  55 static inline void raw_safe_halt(void)
  56 {
  57         __asm__ __volatile__("sti; hlt" : : : "memory");
  58 }
  59
  60 /*
  61  * Used when interrupts are already enabled or to
  62  * shutdown the processor:
  63  */
  64 static inline void halt(void)
  65 {
  66         __asm__ __volatile__("hlt": : :"memory");
  67 }
  68
  69 static inline int raw_irqs_disabled_flags(unsigned long flags)
  70 {
  71         return !(flags & (1 << 9));
  72 }
  73
  74 static inline int raw_irqs_disabled(void)
  75 {
  76         unsigned long flags = __raw_local_save_flags();
  77
  78         return raw_irqs_disabled_flags(flags);
  79 }
  80
  81 /*
  82  * For spinlocks, etc:
  83  */
  84 static inline unsigned long __raw_local_irq_save(void)
  85 {
  86         unsigned long flags = __raw_local_save_flags();
  87
  88         raw_local_irq_disable();
  89
  90         return flags;
  91 }
  92
  93 #define raw_local_irq_save(flags) \
  94                 do { (flags) = __raw_local_irq_save(); } while (0)
  95
  96 #endif /* __ASSEMBLY__ */
  97
  98 /*
  99  * Do the CPU's IRQ-state tracing from assembly code. We call a
 100  * C function, so save all the C-clobbered registers:
 101  */
 102 #ifdef CONFIG_TRACE_IRQFLAGS
 103
 104 # define TRACE_IRQS_ON                          \
 105         pushl %eax;                             \
 106         pushl %ecx;                             \
 107         pushl %edx;                             \
 108         call trace_hardirqs_on;                 \
 109         popl %edx;                              \
 110         popl %ecx;                              \
 111         popl %eax;
 112
 113 # define TRACE_IRQS_OFF                         \
 114         pushl %eax;                             \
 115         pushl %ecx;                             \
 116         pushl %edx;                             \
 117         call trace_hardirqs_off;                \
 118         popl %edx;                              \
 119         popl %ecx;                              \
 120         popl %eax;
 121
 122 #else
 123 # define TRACE_IRQS_ON
 124 # define TRACE_IRQS_OFF
 125 #endif
 126
 127 #endif