The patch 3 adds implementation for queued-based locking on ARM64, and the option in kernel config to enable it. Patches 1 and 2 fix some mess in header files to apply patch 3 smoothly.
Tested on QDF2400 with huge improvements with these patches on the torture tests, by Adam Wallis. Tested on ThunderX, by Andrew Pinski: 120 thread (30 core - 4 thread/core) CN99xx (single socket): benchmark Units qspinlocks vs ticket locks sched/messaging s 73.91% sched/pipe ops/s 104.18% futex/hash ops/s 103.87% futex/wake ms 71.04% futex/wake-parallel ms 93.88% futex/requeue ms 96.47% futex/lock-pi ops/s 118.33% Notice, there's the queued locks implementation for the Power PC introduced by Pan Xinhui. He largely tested it and also found significant performance gain. In arch part it is very similar to this patch though. https://lwn.net/Articles/701137/ RFC: https://www.spinics.net/lists/arm-kernel/msg575575.html v1: - queued_spin_unlock_wait() and queued_spin_is_locked() are re-implemented in arch part to add additional memory barriers; - queued locks are made optional, ticket locks are enabled by default. Jan Glauber (1): arm64/locking: qspinlocks and qrwlocks support Yury Norov (2): kernel/locking: #include <asm/spinlock.h> in qrwlock.c asm-generic: don't #include <linux/atomic.h> in qspinlock_types.h arch/arm64/Kconfig | 24 +++++++++++++++++++ arch/arm64/include/asm/qrwlock.h | 7 ++++++ arch/arm64/include/asm/qspinlock.h | 42 +++++++++++++++++++++++++++++++++ arch/arm64/include/asm/spinlock.h | 12 ++++++++++ arch/arm64/include/asm/spinlock_types.h | 14 ++++++++--- arch/arm64/kernel/Makefile | 1 + arch/arm64/kernel/qspinlock.c | 34 ++++++++++++++++++++++++++ include/asm-generic/qspinlock.h | 1 + include/asm-generic/qspinlock_types.h | 8 ------- kernel/locking/qrwlock.c | 1 + 10 files changed, 133 insertions(+), 11 deletions(-) create mode 100644 arch/arm64/include/asm/qrwlock.h create mode 100644 arch/arm64/include/asm/qspinlock.h create mode 100644 arch/arm64/kernel/qspinlock.c -- 2.11.0
