Messages in this thread Patch in this message | | | Date | Mon, 18 Aug 2008 11:45:28 -0700 | From | Greg KH <> | Subject | [patch 52/60] x86: fix spin_is_contended() |
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2.6.26-stable review patch. If anyone has any objections, please let us know.
------------------ From: Jan Beulich <jbeulich@novell.com>
commit 7bc069c6bc4ede519a7116be1b9e149a1dbf787a upstream
The masked difference is what needs to be compared against 1, rather than the difference of masked values (which can be negative).
Signed-off-by: Jan Beulich <jbeulich@novell.com> Acked-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
--- include/asm-x86/spinlock.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
--- a/include/asm-x86/spinlock.h +++ b/include/asm-x86/spinlock.h @@ -65,7 +65,7 @@ static inline int __raw_spin_is_contende { int tmp = ACCESS_ONCE(lock->slock); - return (((tmp >> 8) & 0xff) - (tmp & 0xff)) > 1; + return (((tmp >> 8) - tmp) & 0xff) > 1; } static __always_inline void __raw_spin_lock(raw_spinlock_t *lock) @@ -129,7 +129,7 @@ static inline int __raw_spin_is_contende { int tmp = ACCESS_ONCE(lock->slock); - return (((tmp >> 16) & 0xffff) - (tmp & 0xffff)) > 1; + return (((tmp >> 16) - tmp) & 0xffff) > 1; } static __always_inline void __raw_spin_lock(raw_spinlock_t *lock) --
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