include/asm-i386/softirq.h

   1 #ifndef __ASM_SOFTIRQ_H
   2 #define __ASM_SOFTIRQ_H
   3
   4 #include <asm/atomic.h>
   5 #include <asm/hardirq.h>
   6
   7 #define __cpu_bh_enable(cpu) \
   8                 do { barrier(); local_bh_count(cpu)--; } while (0)
   9 #define cpu_bh_disable(cpu) \
  10                 do { local_bh_count(cpu)++; barrier(); } while (0)
  11
  12 #define local_bh_disable()      cpu_bh_disable(smp_processor_id())
  13 #define __local_bh_enable()     __cpu_bh_enable(smp_processor_id())
  14
  15 #define in_softirq() (local_bh_count(smp_processor_id()) != 0)
  16
  17 /*
  18  * NOTE: this assembly code assumes:
  19  *
  20  *    (char *)&local_bh_count - 8 == (char *)&softirq_pending
  21  *
  22  * If you change the offsets in irq_stat then you have to
  23  * update this code as well.
  24  */
  25 #define local_bh_enable()                                               \
  26 do {                                                                    \
  27         unsigned int *ptr = &local_bh_count(smp_processor_id());        \
  28                                                                         \
  29         barrier();                                                      \
  30         if (!--*ptr)                                                    \
  31                 __asm__ __volatile__ (                                  \
  32                         "cmpl $0, -8(%0);"                              \
  33                         "jnz 2f;"                                       \
  34                         "1:;"                                           \
  35                                                                         \
  36                         LOCK_SECTION_START("")                          \
  37                         "2: pushl %%eax; pushl %%ecx; pushl %%edx;"     \
  38                         "call %c1;"                                     \
  39                         "popl %%edx; popl %%ecx; popl %%eax;"           \
  40                         "jmp 1b;"                                       \
  41                         LOCK_SECTION_END                                \
  42                                                                         \
  43                 : /* no output */                                       \
  44                 : "r" (ptr), "i" (do_softirq)                           \
  45                 /* no registers clobbered */ );                         \
  46 } while (0)
  47
  48 #endif  /* __ASM_SOFTIRQ_H */