release/src-rt-6.x.4708/linux/linux-2.6.36/arch/sparc/include/asm/backoff.h

   1 #ifndef _SPARC64_BACKOFF_H
   2 #define _SPARC64_BACKOFF_H
   3
   4 #define BACKOFF_LIMIT   (4 * 1024)
   5
   6 #ifdef CONFIG_SMP
   7
   8 #define BACKOFF_SETUP(reg)      \
   9         mov     1, reg
  10
  11 #define BACKOFF_LABEL(spin_label, continue_label) \
  12         spin_label
  13
  14 #define BACKOFF_SPIN(reg, tmp, label)   \
  15         mov     reg, tmp; \
  16 88:     brnz,pt tmp, 88b; \
  17          sub    tmp, 1, tmp; \
  18         set     BACKOFF_LIMIT, tmp; \
  19         cmp     reg, tmp; \
  20         bg,pn   %xcc, label; \
  21          nop; \
  22         ba,pt   %xcc, label; \
  23          sllx   reg, 1, reg;
  24
  25 #else
  26
  27 #define BACKOFF_SETUP(reg)
  28
  29 #define BACKOFF_LABEL(spin_label, continue_label) \
  30         continue_label
  31
  32 #define BACKOFF_SPIN(reg, tmp, label)
  33
  34 #endif
  35
  36 #endif /* _SPARC64_BACKOFF_H */