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[MIPS] Fix __raw_read_trylock() to allow multiple readers

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A deadlock can occur for mixed irq and non-irq rwlock readers if a 2nd
reader attempts to take lock by looping around __raw_read_trylock().

Signed-off-by: Dave Johnson <djohnson+linux-mips@sw.starentnetworks.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
This commit is contained in:
Dave Johnson 2007-03-05 20:50:27 -05:00 committed by Ralf Baechle
parent d0c91ae2bb
commit d52c2d5a62
1 changed files with 2 additions and 2 deletions
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4
include/asm-mips/spinlock.h
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@ -287,7 +287,7 @@ static inline int __raw_read_trylock(raw_rwlock_t *rw)
" .set noreorder # __raw_read_trylock \n"
" li %2, 0 \n"
"1: ll %1, %3 \n"
" bnez %1, 2f \n"
" bltz %1, 2f \n"
" addu %1, 1 \n"
" sc %1, %0 \n"
" .set reorder \n"
@ -304,7 +304,7 @@ static inline int __raw_read_trylock(raw_rwlock_t *rw)
" .set noreorder # __raw_read_trylock \n"
" li %2, 0 \n"
"1: ll %1, %3 \n"
" bnez %1, 2f \n"
" bltz %1, 2f \n"
" addu %1, 1 \n"
" sc %1, %0 \n"
" beqz %1, 1b \n"