Commit 50952026 authored by Ralf Baechle's avatar Ralf Baechle

[MIPS] Fix bug in atomic_sub_if_positive.

The branch optimization fixes in 2.6.21 introduced a bug in
atomic_sub_if_positive that causes it to return even when the sc
instruction fails. The result is that e.g. down_trylock becomes unreliable
as the semaphore counter is not always decremented.

Original MUA-shredded patch from Morten Larsen <mlarsen@broadcom.com>.
Signed-off-by: default avatarRalf Baechle <ralf@linux-mips.org>
parent bf9127c3
......@@ -283,10 +283,10 @@ static __inline__ int atomic_sub_if_positive(int i, atomic_t * v)
" beqz %0, 2f \n"
" subu %0, %1, %3 \n"
" .set reorder \n"
"1: \n"
" .subsection 2 \n"
"2: b 1b \n"
" .previous \n"
"1: \n"
" .set mips0 \n"
: "=&r" (result), "=&r" (temp), "=m" (v->counter)
: "Ir" (i), "m" (v->counter)
......@@ -664,10 +664,10 @@ static __inline__ long atomic64_sub_if_positive(long i, atomic64_t * v)
" beqz %0, 2f \n"
" dsubu %0, %1, %3 \n"
" .set reorder \n"
"1: \n"
" .subsection 2 \n"
"2: b 1b \n"
" .previous \n"
"1: \n"
" .set mips0 \n"
: "=&r" (result), "=&r" (temp), "=m" (v->counter)
: "Ir" (i), "m" (v->counter)
......
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