diff options
| author | Ralf Baechle <ralf@linux-mips.org> | 2008-07-03 18:28:35 -0400 |
|---|---|---|
| committer | Ralf Baechle <ralf@linux-mips.org> | 2008-07-04 03:22:15 -0400 |
| commit | 50952026036c7b4212b90091bf23a264c0ccc1fb (patch) | |
| tree | 50c5865ab0fdc8d4f36a69ddcc86037489a90fa9 | |
| parent | bf9127c36341573dc47a9c2fc003dcf13bbbf246 (diff) | |
[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: Ralf Baechle <ralf@linux-mips.org>
| -rw-r--r-- | include/asm-mips/atomic.h | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/include/asm-mips/atomic.h b/include/asm-mips/atomic.h index a798d6299a79..1232be3885b0 100644 --- a/include/asm-mips/atomic.h +++ b/include/asm-mips/atomic.h | |||
| @@ -283,10 +283,10 @@ static __inline__ int atomic_sub_if_positive(int i, atomic_t * v) | |||
| 283 | " beqz %0, 2f \n" | 283 | " beqz %0, 2f \n" |
| 284 | " subu %0, %1, %3 \n" | 284 | " subu %0, %1, %3 \n" |
| 285 | " .set reorder \n" | 285 | " .set reorder \n" |
| 286 | "1: \n" | ||
| 287 | " .subsection 2 \n" | 286 | " .subsection 2 \n" |
| 288 | "2: b 1b \n" | 287 | "2: b 1b \n" |
| 289 | " .previous \n" | 288 | " .previous \n" |
| 289 | "1: \n" | ||
| 290 | " .set mips0 \n" | 290 | " .set mips0 \n" |
| 291 | : "=&r" (result), "=&r" (temp), "=m" (v->counter) | 291 | : "=&r" (result), "=&r" (temp), "=m" (v->counter) |
| 292 | : "Ir" (i), "m" (v->counter) | 292 | : "Ir" (i), "m" (v->counter) |
| @@ -664,10 +664,10 @@ static __inline__ long atomic64_sub_if_positive(long i, atomic64_t * v) | |||
| 664 | " beqz %0, 2f \n" | 664 | " beqz %0, 2f \n" |
| 665 | " dsubu %0, %1, %3 \n" | 665 | " dsubu %0, %1, %3 \n" |
| 666 | " .set reorder \n" | 666 | " .set reorder \n" |
| 667 | "1: \n" | ||
| 668 | " .subsection 2 \n" | 667 | " .subsection 2 \n" |
| 669 | "2: b 1b \n" | 668 | "2: b 1b \n" |
| 670 | " .previous \n" | 669 | " .previous \n" |
| 670 | "1: \n" | ||
| 671 | " .set mips0 \n" | 671 | " .set mips0 \n" |
| 672 | : "=&r" (result), "=&r" (temp), "=m" (v->counter) | 672 | : "=&r" (result), "=&r" (temp), "=m" (v->counter) |
| 673 | : "Ir" (i), "m" (v->counter) | 673 | : "Ir" (i), "m" (v->counter) |