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| author | David S. Miller <davem@davemloft.net> | 2010-08-19 05:53:26 (GMT) |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2010-08-19 05:53:26 (GMT) |
| commit | 0f58189d4a3ca96d7959501ecb203177efdbc5bd (patch) | |
| tree | b5ad2f63da4c1caa5d20487cf370d51e4392111c /arch/sparc/include | |
| parent | 6ec274750c99448c3412bbc10c97ce0c993f8a4e (diff) | |
| download | linux-0f58189d4a3ca96d7959501ecb203177efdbc5bd.tar.xz | |
sparc64: Make lock backoff really a NOP on UP builds.
As noticed by Mikulas Patocka, the backoff macros don't
completely nop out for UP builds, we still get a
branch always and a delay slot nop.
Fix this by making the branch to the backoff spin loop
selective, then we can nop out the spin loop completely.
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'arch/sparc/include')
| -rw-r--r-- | arch/sparc/include/asm/backoff.h | 11 |
1 files changed, 8 insertions, 3 deletions
diff --git a/arch/sparc/include/asm/backoff.h b/arch/sparc/include/asm/backoff.h index fa1fdf6..db3af0d 100644 --- a/arch/sparc/include/asm/backoff.h +++ b/arch/sparc/include/asm/backoff.h @@ -8,6 +8,9 @@ #define BACKOFF_SETUP(reg) \ mov 1, reg +#define BACKOFF_LABEL(spin_label, continue_label) \ + spin_label + #define BACKOFF_SPIN(reg, tmp, label) \ mov reg, tmp; \ 88: brnz,pt tmp, 88b; \ @@ -22,9 +25,11 @@ #else #define BACKOFF_SETUP(reg) -#define BACKOFF_SPIN(reg, tmp, label) \ - ba,pt %xcc, label; \ - nop; + +#define BACKOFF_LABEL(spin_label, continue_label) \ + continue_label + +#define BACKOFF_SPIN(reg, tmp, label) #endif |