Hello, This version is a complete rewrite of the syscall (thanks Thomas for the suggestions!).
* Use case The use-case for the new syscalls is detailed in the last patch version: https://lore.kernel.org/lkml/[email protected] * The syscall interface Documented at patches 3/9 "futex: Create set_robust_list2() syscall" and 4/9 "futex: Create get_robust_list2() syscall". * Testing I expanded the current robust list selftest to use the new interface, and also ported the original syscall to use the new syscall internals, and everything survived the tests. * Changelog Changes from v5: - Complete interface rewrite, there are so many changes but the main ones are the following points - Array of robust lists now has a static size, allocated once during the first usage of the list - Now that the list of robust lists have a fixed size, I removed the logic of having a command for creating a new index on the list. To simplify things for everyone, userspace just need to call set_robust_list2(head, 32-bit/64-bit type, index). - Created get_robust_list2() - The new code can be better integrated with the original interface - v5: https://lore.kernel.org/r/[email protected] Feedback is very welcomed! --- André Almeida (9): futex: Use explicit sizes for compat_robust_list structs futex: Make exit_robust_list32() unconditionally available for 64-bit kernels futex: Create set_robust_list2() syscall futex: Create get_robust_list2() syscall futex: Wire up set_robust_list2 syscall futex: Wire up get_robust_list2 syscall selftests/futex: Expand for set_robust_list2() selftests/futex: Expand for get_robust_list2() futex: Use new robust list API internally arch/alpha/kernel/syscalls/syscall.tbl | 2 + arch/arm/tools/syscall.tbl | 2 + arch/m68k/kernel/syscalls/syscall.tbl | 2 + arch/microblaze/kernel/syscalls/syscall.tbl | 2 + arch/mips/kernel/syscalls/syscall_n32.tbl | 2 + arch/mips/kernel/syscalls/syscall_n64.tbl | 2 + arch/mips/kernel/syscalls/syscall_o32.tbl | 2 + arch/parisc/kernel/syscalls/syscall.tbl | 2 + arch/powerpc/kernel/syscalls/syscall.tbl | 2 + arch/s390/kernel/syscalls/syscall.tbl | 2 + arch/sh/kernel/syscalls/syscall.tbl | 2 + arch/sparc/kernel/syscalls/syscall.tbl | 2 + arch/x86/entry/syscalls/syscall_32.tbl | 2 + arch/x86/entry/syscalls/syscall_64.tbl | 2 + arch/xtensa/kernel/syscalls/syscall.tbl | 2 + include/linux/compat.h | 13 +- include/linux/futex.h | 30 +- include/linux/sched.h | 6 +- include/uapi/asm-generic/unistd.h | 7 +- include/uapi/linux/futex.h | 26 ++ kernel/futex/core.c | 140 ++++-- kernel/futex/syscalls.c | 134 +++++- kernel/sys_ni.c | 2 + scripts/syscall.tbl | 1 + .../selftests/futex/functional/robust_list.c | 504 +++++++++++++++++++-- 25 files changed, 788 insertions(+), 105 deletions(-) --- base-commit: c42ba5a87bdccbca11403b7ca8bad1a57b833732 change-id: 20250225-tonyk-robust_futex-60adeedac695 Best regards, -- André Almeida <[email protected]>
