Hi Ingo, Hi Peter, Please let me know if you find anything that prevents you from integrating this patchset into the scheduler tree. Thanks, Mathieu ----- On Jan 23, 2018, at 10:57 AM, Mathieu Desnoyers mathieu.desnoyers@xxxxxxxxxxxx wrote: > Hi Ingo, Peter, Thomas, > > Here is the updated membarrier patch series following review from > Andy. > > It would be appreciated of those can go through the scheduler tree for > the 4.16 merge window. > > Patch "x86: Implement sync_core_before_usermode" got a reviewed-by from > Thomas, but I removed the tag following KPTI-related optimizations based > on the discussion with Andy afterwards. > > Highlights: > > "powerpc: membarrier: Skip memory barrier in switch_mm()" takes care of > a TODO that was left in the private expedited implementation when merged > in 4.14: an extra memory barrier was added on context switch on powerpc. > Ensure that the barrier is only performed when scheduling between > different processes, only for threads belonging to processes that have > registered their intent to use the private expedited command. > > "membarrier: provide GLOBAL_EXPEDITED command" adds new commands to > membarrier for registration and use of membarrier across processes > communicating through shared memory mappings. The non-expedited command > has proven to be really too slow (taking 10ms and more to complete) for > real-world use. The expedited version completes in a matter of > microseconds. This patch renames the pre-existing MEMBARRIER_CMD_SHARED > to MEMBARRIER_CMD_GLOBAL for consistency, keeping the old enum label > as an alias for backward compatibility. > > "membarrier: Provide core serializing command" provides core > serialization for JIT reclaim. We received positive feedback from > Android developers that the proposed ABI fits their use-case. > Only x86 32/64 and arm 64 implement this command so far. This is > opt-in per architecture. > > The other patches add selftests and documentation. > > Thanks, > > Mathieu > > Mathieu Desnoyers (11): > membarrier: selftest: Test private expedited cmd (v2) > powerpc: membarrier: Skip memory barrier in switch_mm() (v7) > membarrier: Document scheduler barrier requirements (v5) > membarrier: provide GLOBAL_EXPEDITED command (v3) > membarrier: selftest: Test global expedited cmd (v2) > Introduce sync_core_before_usermode (v2) > x86: Implement sync_core_before_usermode (v3) > membarrier: Provide core serializing command (v2) > membarrier: x86: Provide core serializing command (v4) > membarrier: arm64: Provide core serializing command > membarrier: selftest: Test private expedited sync core cmd > > MAINTAINERS | 1 + > arch/arm64/Kconfig | 1 + > arch/arm64/kernel/entry.S | 4 + > arch/powerpc/Kconfig | 1 + > arch/powerpc/include/asm/membarrier.h | 27 +++ > arch/powerpc/mm/mmu_context.c | 7 + > arch/x86/Kconfig | 2 + > arch/x86/entry/entry_32.S | 5 + > arch/x86/entry/entry_64.S | 4 + > arch/x86/include/asm/sync_core.h | 28 +++ > arch/x86/mm/tlb.c | 6 + > include/linux/sched/mm.h | 40 +++- > include/linux/sync_core.h | 21 ++ > include/uapi/linux/membarrier.h | 74 ++++++- > init/Kconfig | 9 + > kernel/sched/core.c | 53 +++-- > kernel/sched/membarrier.c | 177 +++++++++++++-- > .../testing/selftests/membarrier/membarrier_test.c | 237 +++++++++++++++++++-- > 18 files changed, 629 insertions(+), 68 deletions(-) > create mode 100644 arch/powerpc/include/asm/membarrier.h > create mode 100644 arch/x86/include/asm/sync_core.h > create mode 100644 include/linux/sync_core.h > > -- > 2.11.0 -- Mathieu Desnoyers EfficiOS Inc. http://www.efficios.com -- To unsubscribe from this list: send the line "unsubscribe linux-api" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
