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| author | Nicholas Piggin <npiggin@gmail.com> | 2020-07-24 23:14:21 +1000 |
|---|---|---|
| committer | Michael Ellerman <mpe@ellerman.id.au> | 2020-07-27 00:01:29 +1000 |
| commit | 20c0e8269e9d515e677670902c7e1cc0209d6ad9 (patch) | |
| tree | 1de7272a98830301f6d21a1b8cdab7d28d0e83c1 /arch/powerpc/include/asm/spinlock.h | |
| parent | aa65ff6b18e0366db1790609956a4ac7308c5668 (diff) | |
| download | lwn-20c0e8269e9d515e677670902c7e1cc0209d6ad9.tar.gz lwn-20c0e8269e9d515e677670902c7e1cc0209d6ad9.zip | |
powerpc/pseries: Implement paravirt qspinlocks for SPLPAR
This implements the generic paravirt qspinlocks using H_PROD and
H_CONFER to kick and wait.
This uses an un-directed yield to any CPU rather than the directed
yield to a pre-empted lock holder that paravirtualised simple
spinlocks use, that requires no kick hcall. This is something that
could be investigated and improved in future.
Performance results can be found in the commit which added queued
spinlocks.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Waiman Long <longman@redhat.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200724131423.1362108-5-npiggin@gmail.com
Diffstat (limited to 'arch/powerpc/include/asm/spinlock.h')
| -rw-r--r-- | arch/powerpc/include/asm/spinlock.h | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/arch/powerpc/include/asm/spinlock.h b/arch/powerpc/include/asm/spinlock.h index 434615f1d761..6ec72282888d 100644 --- a/arch/powerpc/include/asm/spinlock.h +++ b/arch/powerpc/include/asm/spinlock.h @@ -10,5 +10,9 @@ #include <asm/simple_spinlock.h> #endif +#ifndef CONFIG_PARAVIRT_SPINLOCKS +static inline void pv_spinlocks_init(void) { } +#endif + #endif /* __KERNEL__ */ #endif /* __ASM_SPINLOCK_H */ |