Here are the membarrier changes I plan on sending for the 4.15 merge window.
This series includes selftests improvements for sys_membarrier, improvement of powerpc handling of the memory barrier required by sys_membarrier in switch_mm(), and adds a new core serializing membarrier, currently only implemented on x86. Architectures wishing to provide the core serializing membarrier need to select ARCH_HAS_MEMBARRIER_SYNC_CORE and document how they provide the core serialization required by that command in their architecture code. Andy, I know you told me you had changes coming up in x86 entry.S for 4.15, but I figure that managing the merge conflict between your changes in 4.15 and those added comments should be straightforward. Anyway, I kind of suspect that at any given point in time you will always have changes of some sort to propose to entry.S, so now seems to be a time as appropriate as ever to push the core serializing membarrier comments. Feedback is welcome! Thanks, Mathieu Mathieu Desnoyers (6): membarrier: selftest: Test private expedited cmd membarrier: powerpc: Skip memory barrier in switch_mm() (v6) membarrier: Document scheduler barrier requirements (v5) membarrier: Provide core serializing command membarrier: x86: Provide core serializing command membarrier: selftest: Test private expedited sync core cmd MAINTAINERS | 2 + arch/powerpc/Kconfig | 1 + arch/powerpc/include/asm/membarrier.h | 32 ++++ arch/powerpc/kernel/Makefile | 2 + arch/powerpc/kernel/membarrier.c | 37 ++++ arch/powerpc/mm/mmu_context.c | 7 + arch/x86/Kconfig | 2 + arch/x86/entry/entry_32.S | 5 + arch/x86/entry/entry_64.S | 8 + arch/x86/include/asm/membarrier.h | 36 ++++ arch/x86/kernel/Makefile | 1 + arch/x86/kernel/membarrier.c | 39 +++++ arch/x86/mm/tlb.c | 6 + include/linux/sched/mm.h | 36 +++- include/uapi/linux/membarrier.h | 14 +- init/Kconfig | 6 + kernel/sched/core.c | 53 +++--- kernel/sched/membarrier.c | 55 ++++-- .../testing/selftests/membarrier/membarrier_test.c | 186 +++++++++++++++++++-- 19 files changed, 470 insertions(+), 58 deletions(-) create mode 100644 arch/powerpc/include/asm/membarrier.h create mode 100644 arch/powerpc/kernel/membarrier.c create mode 100644 arch/x86/include/asm/membarrier.h create mode 100644 arch/x86/kernel/membarrier.c -- 2.11.0
