User Managed Concurrency Groups (UMCG) is an M:N threading subsystem/toolkit that lets user space application developers implement in-process user space schedulers. Key changes from the previous patchset https://lore.kernel.org/all/20211012232522.714898-1-posk@xxxxxxxxxx/: - added libumcg tools/lib/umcg; - worker "wakeup" is reworked so that it is now purely a userspace op, instead of waking the thread in order for it to block on return to the userspace immediately; - a couple of minor fixes and refactorings. These big things remain to be addressed (in no particular order): - support tracing/debugging - make context switches faster (see umcg_do_context_switch in umcg.c) - support other architectures - cleanup and post selftests in tools/testing/selftests/umcg/ - allow cross-mm wakeups (securely) Peter Oskolkov (6): sched/umcg: add WF_CURRENT_CPU and externise ttwu mm, x86/uaccess: add userspace atomic helpers sched/umcg: implement UMCG syscalls sched/umcg, lib/umcg: implement libumcg sched/umcg: add Documentation/userspace-api/umcg.txt sched/umcg, lib/umcg: add tools/lib/umcg/libumcg.txt Documentation/userspace-api/umcg.txt | 598 ++++++++++++ arch/x86/entry/syscalls/syscall_64.tbl | 2 + arch/x86/include/asm/uaccess_64.h | 93 ++ fs/exec.c | 1 + include/linux/sched.h | 71 ++ include/linux/syscalls.h | 3 + include/linux/uaccess.h | 46 + include/uapi/asm-generic/unistd.h | 6 +- include/uapi/linux/umcg.h | 137 +++ init/Kconfig | 10 + kernel/entry/common.c | 4 +- kernel/exit.c | 5 + kernel/sched/Makefile | 1 + kernel/sched/core.c | 12 +- kernel/sched/fair.c | 4 + kernel/sched/sched.h | 15 +- kernel/sched/umcg.c | 949 +++++++++++++++++++ kernel/sys_ni.c | 4 + mm/maccess.c | 264 ++++++ tools/lib/umcg/.gitignore | 4 + tools/lib/umcg/Makefile | 11 + tools/lib/umcg/libumcg.c | 1201 ++++++++++++++++++++++++ tools/lib/umcg/libumcg.h | 299 ++++++ tools/lib/umcg/libumcg.txt | 438 +++++++++ 24 files changed, 4166 insertions(+), 12 deletions(-) create mode 100644 Documentation/userspace-api/umcg.txt create mode 100644 include/uapi/linux/umcg.h create mode 100644 kernel/sched/umcg.c create mode 100644 tools/lib/umcg/.gitignore create mode 100644 tools/lib/umcg/Makefile create mode 100644 tools/lib/umcg/libumcg.c create mode 100644 tools/lib/umcg/libumcg.h create mode 100644 tools/lib/umcg/libumcg.txt base-commit: 8ea9183db4ad8afbcb7089a77c23eaf965b0cacd -- 2.25.1
