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Directed yield: direct yield of spinlocks for powerpc.

PATCH In review Martin Schwidefsky 2 participants 2 messages Sep 19, 2006 – Sep 21, 2006 Generic include/asm header files

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Martin Schwidefsky

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PATCH 2/3 Directed yield: direct yield of spinlocks for powerpc.

From: Martin Schwidefsky <[email protected]>

[patch 2/3] Directed yield: direct yield of spinlocks for powerpc.

Powerpc already has a directed yield for CONFIG_PREEMPT="n". To make it work with CONFIG_PREEMPT="y" as well the _raw_{spin,read,write}_relax primitives need to be defined to call __spin_yield() for spinlocks and __rw_yield() for rw-locks.

Cc Paul Mackerras <[email protected]>
Signed-off-by Martin Schwidefsky <[email protected]>

---

 include/asm-powerpc/spinlock.h |    6 +++---
 1 files changed, 3 insertions(+), 3 deletions(-)
include/asm-powerpc/spinlock.h +3 -3
diff -urpN linux-2.6/include/asm-powerpc/spinlock.h linux-2.6-patched/include/asm-powerpc/spinlock.h
@@ -285,9 +285,9 @@ static __inline__ void __raw_write_unloc
 	rw->lock = 0;
 }
 
-#define _raw_spin_relax(lock)	cpu_relax()
-#define _raw_read_relax(lock)	cpu_relax()
-#define _raw_write_relax(lock)	cpu_relax()
+#define _raw_spin_relax(lock)	__spin_yield(lock)
+#define _raw_read_relax(lock)	__rw_yield(lock)
+#define _raw_write_relax(lock)	__rw_yield(lock)
 
 #endif /* __KERNEL__ */
 #endif /* __ASM_SPINLOCK_H */
Acked-by on v1 2/3
#1 lore raw
Quoted 4 lines · Martin Schwidefsky

Powerpc already has a directed yield for CONFIG_PREEMPT="n". To make it work with CONFIG_PREEMPT="y" as well the _raw_{spin,read,write}_relax primitives need to be defined to call __spin_yield() for spinlocks and __rw_yield() for rw-locks.

Acked-by Paul Mackerras <[email protected]>