# git rev-parse -q --verify de8a34242c88473ee615f66a7ded095f094e708e^{commit} de8a34242c88473ee615f66a7ded095f094e708e already have revision, skipping fetch # git checkout -q -f -B kisskb de8a34242c88473ee615f66a7ded095f094e708e # git clean -qxdf # < git log -1 # commit de8a34242c88473ee615f66a7ded095f094e708e # Author: Nicholas Piggin # Date: Thu Jul 9 17:07:59 2020 +1000 # # lazy tlb: shoot lazies, a non-refcounting lazy tlb option # # On big systems, the mm refcount can become highly contented when doing # a lot of context switching with threaded applications (particularly # switching between the idle thread and an application thread). # # Abandoning lazy tlb slows switching down quite a bit in the important # user->idle->user cases, so so instead implement a non-refcounted scheme # that causes __mmdrop() to IPI all CPUs in the mm_cpumask and shoot down # any remaining lazy ones. # # On a 16-socket 192-core POWER8 system, a context switching benchmark # with as many software threads as CPUs (so each switch will go in and # out of idle), upstream can achieve a rate of about 1 million context # switches per second. After this patch it goes up to 118 million. # # Signed-off-by: Nicholas Piggin # < /opt/cross/kisskb/korg/gcc-4.9.4-nolibc/powerpc64-linux/bin/powerpc64-linux-gcc --version # < /opt/cross/kisskb/korg/gcc-4.9.4-nolibc/powerpc64-linux/bin/powerpc64-linux-ld --version # < git log --format=%s --max-count=1 de8a34242c88473ee615f66a7ded095f094e708e # < make -s -j 48 ARCH=powerpc O=/kisskb/build/npiggin_powerpc-allnoconfig_powerpc-gcc4.9 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-4.9.4-nolibc/powerpc64-linux/bin/powerpc64-linux- allnoconfig # < make -s -j 48 ARCH=powerpc O=/kisskb/build/npiggin_powerpc-allnoconfig_powerpc-gcc4.9 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-4.9.4-nolibc/powerpc64-linux/bin/powerpc64-linux- help # make -s -j 48 ARCH=powerpc O=/kisskb/build/npiggin_powerpc-allnoconfig_powerpc-gcc4.9 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-4.9.4-nolibc/powerpc64-linux/bin/powerpc64-linux- olddefconfig # make -s -j 48 ARCH=powerpc O=/kisskb/build/npiggin_powerpc-allnoconfig_powerpc-gcc4.9 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-4.9.4-nolibc/powerpc64-linux/bin/powerpc64-linux- Completed OK # rm -rf /kisskb/build/npiggin_powerpc-allnoconfig_powerpc-gcc4.9 # Build took: 0:00:20.458567