diff options
| author | Jens Axboe <axboe@kernel.dk> | 2018-02-07 15:54:20 -0700 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2018-02-07 15:54:20 -0700 |
| commit | 61a695184fcc8f225327206b88320279dd8684af (patch) | |
| tree | 6cbda2b0e7de94ebad95072d17cc0aa82c9d8ab3 /arch/powerpc/include/asm/membarrier.h | |
| parent | 9e05c864993c5442227f83ae1694a737d7a102ed (diff) | |
| parent | 581e400ff935d34d95811258586128bf11baef15 (diff) | |
Merge branch 'master' into test
* master: (1190 commits)
ASoC: stm32: add of dependency for stm32 drivers
ASoC: mt8173-rt5650: fix child-node lookup
ASoC: dapm: fix debugfs read using path->connected
platform/x86: samsung-laptop: Re-use DEFINE_SHOW_ATTRIBUTE() macro
platform/x86: ideapad-laptop: Re-use DEFINE_SHOW_ATTRIBUTE() macro
platform/x86: dell-laptop: Re-use DEFINE_SHOW_ATTRIBUTE() macro
seq_file: Introduce DEFINE_SHOW_ATTRIBUTE() helper macro
Documentation/sysctl/user.txt: fix typo
MAINTAINERS: update ARM/QUALCOMM SUPPORT patterns
MAINTAINERS: update various PALM patterns
MAINTAINERS: update "ARM/OXNAS platform support" patterns
MAINTAINERS: update Cortina/Gemini patterns
MAINTAINERS: remove ARM/CLKDEV SUPPORT file pattern
MAINTAINERS: remove ANDROID ION pattern
mm: docs: add blank lines to silence sphinx "Unexpected indentation" errors
mm: docs: fix parameter names mismatch
mm: docs: fixup punctuation
pipe: read buffer limits atomically
pipe: simplify round_pipe_size()
pipe: reject F_SETPIPE_SZ with size over UINT_MAX
...
Diffstat (limited to 'arch/powerpc/include/asm/membarrier.h')
| -rw-r--r-- | arch/powerpc/include/asm/membarrier.h | 27 |
1 files changed, 27 insertions, 0 deletions
diff --git a/arch/powerpc/include/asm/membarrier.h b/arch/powerpc/include/asm/membarrier.h new file mode 100644 index 000000000000..6e20bb5c74ea --- /dev/null +++ b/arch/powerpc/include/asm/membarrier.h @@ -0,0 +1,27 @@ +#ifndef _ASM_POWERPC_MEMBARRIER_H +#define _ASM_POWERPC_MEMBARRIER_H + +static inline void membarrier_arch_switch_mm(struct mm_struct *prev, + struct mm_struct *next, + struct task_struct *tsk) +{ + /* + * Only need the full barrier when switching between processes. + * Barrier when switching from kernel to userspace is not + * required here, given that it is implied by mmdrop(). Barrier + * when switching from userspace to kernel is not needed after + * store to rq->curr. + */ + if (likely(!(atomic_read(&next->membarrier_state) & + (MEMBARRIER_STATE_PRIVATE_EXPEDITED | + MEMBARRIER_STATE_GLOBAL_EXPEDITED)) || !prev)) + return; + + /* + * The membarrier system call requires a full memory barrier + * after storing to rq->curr, before going back to user-space. + */ + smp_mb(); +} + +#endif /* _ASM_POWERPC_MEMBARRIER_H */ |