[PATCH 0/3] powerpc: add ticket spinlock

[Kevin Hao]

Hi,

This patch series convert the simple spinlock to ticket-based spinlock for the
platforms without shared processors. I have run the following command ten times
on a t4240rdb board (12 dual-threaded cpus):
	./perf bench sched messaging -g 100

                                Before      After
    Averaged total time [sec]:  2.623       2.479 

We can see a ~5% performance enhancing. I also run the following command ten
times on a p1020rdb board (2 cpus):
	./perf bench sched messaging -g 20 

                                Before      After
    Averaged total time [sec]:  3.139       3.144 

So the overhead for the 2 cpus platform is also trivial. 


Kevin Hao (3):
  powerpc: introduce PPC_HAS_LOCK_OWNER
  powerpc: spinlock: refactor codes wrapped by PPC_HAS_LOCK_OWNER
  powerpc: add ticket spinlock

 arch/powerpc/Kconfig                      |   8 ++
 arch/powerpc/include/asm/spinlock.h       | 144 ++++++++++++++++++++++--------
 arch/powerpc/include/asm/spinlock_types.h |  16 ++++
 arch/powerpc/lib/locks.c                  |   4 +-
 arch/powerpc/platforms/pseries/Kconfig    |   1 +
 5 files changed, 133 insertions(+), 40 deletions(-)

-- 
2.1.0