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| author | Benjamin Herrenschmidt <benh@kernel.crashing.org> | 2017-07-24 14:28:02 +1000 |
|---|---|---|
| committer | Michael Ellerman <mpe@ellerman.id.au> | 2017-08-23 22:28:38 +1000 |
| commit | a619e59c075c66e530a88e57b45bb0417e2f4fff (patch) | |
| tree | 5f725ed75bdccc3bbd715ae8fb400ae0e55062b2 /arch/powerpc/include/asm/mmu_context.h | |
| parent | b426e4bd77fa2f03723cc0bada80b00c664f67da (diff) | |
| download | blackbird-op-linux-a619e59c075c66e530a88e57b45bb0417e2f4fff.tar.gz blackbird-op-linux-a619e59c075c66e530a88e57b45bb0417e2f4fff.zip | |
powerpc/mm: Optimize detection of thread local mm's
Instead of comparing the whole CPU mask every time, let's
keep a counter of how many bits are set in the mask. Thus
testing for a local mm only requires testing if that counter
is 1 and the current CPU bit is set in the mask.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Diffstat (limited to 'arch/powerpc/include/asm/mmu_context.h')
| -rw-r--r-- | arch/powerpc/include/asm/mmu_context.h | 9 |
1 files changed, 9 insertions, 0 deletions
diff --git a/arch/powerpc/include/asm/mmu_context.h b/arch/powerpc/include/asm/mmu_context.h index fb99c27bbf5e..2338abf6101a 100644 --- a/arch/powerpc/include/asm/mmu_context.h +++ b/arch/powerpc/include/asm/mmu_context.h @@ -96,6 +96,14 @@ static inline void switch_mm_pgdir(struct task_struct *tsk, struct mm_struct *mm) { } #endif +#ifdef CONFIG_PPC_BOOK3S_64 +static inline void inc_mm_active_cpus(struct mm_struct *mm) +{ + atomic_inc(&mm->context.active_cpus); +} +#else +static inline void inc_mm_active_cpus(struct mm_struct *mm) { } +#endif /* * switch_mm is the entry point called from the architecture independent @@ -110,6 +118,7 @@ static inline void switch_mm_irqs_off(struct mm_struct *prev, /* Mark this context has been used on the new CPU */ if (!cpumask_test_cpu(smp_processor_id(), mm_cpumask(next))) { cpumask_set_cpu(smp_processor_id(), mm_cpumask(next)); + inc_mm_active_cpus(next); /* * This full barrier orders the store to the cpumask above vs |
