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| author | Ivan Maidanski <ivmai@mail.ru> | 2016-04-06 00:10:56 +0300 |
|---|---|---|
| committer | Ivan Maidanski <ivmai@mail.ru> | 2016-04-06 00:10:56 +0300 |
| commit | 157e8ad79a1bcc3d0ab331ab2217a9b81f35864c (patch) | |
| tree | 726421123a504cc63547e83dc01bfd592e5f3733 | |
| parent | 3315a037247cd7f468d5bd863c52230d05548dcd (diff) | |
| download | libatomic_ops-157e8ad79a1bcc3d0ab331ab2217a9b81f35864c.tar.gz | |
Eliminate redundant lwsync 2nd call in CAS_full on fail (gcc/PowerPC)
* src/atomic_ops/sysdeps/gcc/powerpc.h (AO_compare_and_swap_full,
AO_fetch_compare_and_swap_full): Do not call AO_lwsync 2nd time if
CAS is not successful.
| -rw-r--r-- | src/atomic_ops/sysdeps/gcc/powerpc.h | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/src/atomic_ops/sysdeps/gcc/powerpc.h b/src/atomic_ops/sysdeps/gcc/powerpc.h index 94e83e7..5bee475 100644 --- a/src/atomic_ops/sysdeps/gcc/powerpc.h +++ b/src/atomic_ops/sysdeps/gcc/powerpc.h @@ -227,7 +227,8 @@ AO_test_and_set_full(volatile AO_TS_t *addr) { int result; AO_lwsync(); result = AO_compare_and_swap(addr, old, new_val); - AO_lwsync(); + if (result) + AO_lwsync(); return result; } # define AO_HAVE_compare_and_swap_full @@ -291,7 +292,8 @@ AO_fetch_compare_and_swap_full(volatile AO_t *addr, AO_t old_val, AO_t result; AO_lwsync(); result = AO_fetch_compare_and_swap(addr, old_val, new_val); - AO_lwsync(); + if (result == old_val) + AO_lwsync(); return result; } #define AO_HAVE_fetch_compare_and_swap_full |