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| author | Rich Felker <dalias@aerifal.cx> | 2014-07-27 21:13:37 -0400 |
|---|---|---|
| committer | Rich Felker <dalias@aerifal.cx> | 2014-07-27 21:13:37 -0400 |
| commit | c394763d350f92ff1dbfb79fcd7124da47bc7043 (patch) | |
| tree | 176336ccc95f27c7b1a9a8bead48fb48c839997c | |
| parent | 2068b4e8911a3a49cded44b4568f6c943a8c98f8 (diff) | |
| download | musl-c394763d350f92ff1dbfb79fcd7124da47bc7043.tar.gz | |
fix insufficient synchronization in sh atomic asm
while other usage I've seen only has the synco instruction after the
atomic operation, I cannot find any documentation indicating that this
is correct. certainly all stores before the atomic need to have been
synchronized before the atomic operation takes place.
| -rw-r--r-- | arch/sh/src/atomic.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/arch/sh/src/atomic.c b/arch/sh/src/atomic.c index d29b0538..13395673 100644 --- a/arch/sh/src/atomic.c +++ b/arch/sh/src/atomic.c @@ -1,7 +1,7 @@ #include "libc.h" #define LLSC_CLOBBERS "r0", "t", "memory" -#define LLSC_START(mem) \ +#define LLSC_START(mem) "synco\n" \ "0: movli.l @" mem ", r0\n" #define LLSC_END(mem) \ "1: movco.l r0, @" mem "\n" \ @@ -99,6 +99,7 @@ void __sh_store(volatile int *p, int x) { if (__hwcap & CPU_HAS_LLSC) { __asm__ __volatile__( + " synco\n" " mov.l %1, @%0\n" " synco\n" : : "r"(p), "r"(x) : "memory"); |