From mboxrd@z Thu Jan 1 00:00:00 1970 From: parri.andrea@gmail.com (Andrea Parri) Date: Mon, 5 Mar 2018 19:23:30 +0100 Subject: [RFC PATCH 0/2] riscv/spinlock,atomic: Miscellaneous fixes Message-ID: <1520274210-21748-1-git-send-email-parri.andrea@gmail.com> To: linux-riscv@lists.infradead.org List-Id: linux-riscv.lists.infradead.org Hi, This RFC is a follow-up on the discussion in [1], which led to the discovery of a few issues in the current implementations of RISC-V locking and atomic operations. In summary, this series proposes the following modifications: 1. Use lightweigth fences for acquire/release (locking, atomics) 2. Use the combination of .rl and full fences for fully-ordered atomics implemented with LR/SC pairs. 3. A few style changes (80-chars lines, alignment). Applies on top of "next-smp_sl_ar". Cheers, Andrea [1] https://marc.info/?l=linux-kernel&m=151930201102853&w=2 Andrea Parri (2): riscv/spinlock: Strengthen implementations with fences riscv/atomic: Strengthen implementations with fences arch/riscv/include/asm/atomic.h | 417 ++++++++++++++++++++++++-------------- arch/riscv/include/asm/cmpxchg.h | 391 ++++++++++++++++++++++++++++------- arch/riscv/include/asm/fence.h | 12 ++ arch/riscv/include/asm/spinlock.h | 29 +-- 4 files changed, 615 insertions(+), 234 deletions(-) create mode 100644 arch/riscv/include/asm/fence.h -- 2.7.4