Re: [RFC PATCH v1 04/10] RISC-V: Use IPIs for remote TLB flush when possible
From: Marc Zyngier <maz@kernel.org>
Date: 2021-06-13 09:33:09
Also in:
linux-riscv, lkml
On Sat, 12 Jun 2021 17:04:16 +0100, Anup Patel [off-list ref] wrote:
quoted hunk ↗ jump to hunk
If IPI calls are injected using SBI IPI calls then remote TLB flush using SBI RFENCE calls is much faster because using IPIs for remote TLB flush would still endup as SBI IPI calls with extra processing on kernel side. It is now possible to have specialized hardware (such as RISC-V AIA) which allows S-mode software to directly inject IPIs without any assistance from M-mode runtime firmware. This patch extends remote TLB flush functions to use IPIs whenever underlying IPI operations are suitable for remote FENCEs. Signed-off-by: Anup Patel <redacted> --- arch/riscv/mm/tlbflush.c | 62 +++++++++++++++++++++++++++++++--------- 1 file changed, 48 insertions(+), 14 deletions(-)diff --git a/arch/riscv/mm/tlbflush.c b/arch/riscv/mm/tlbflush.c index 720b443c4528..009c56fa102d 100644 --- a/arch/riscv/mm/tlbflush.c +++ b/arch/riscv/mm/tlbflush.c@@ -1,39 +1,73 @@ // SPDX-License-Identifier: GPL-2.0 +/* + * TLB flush implementation. + * + * Copyright (c) 2021 Western Digital Corporation or its affiliates. + */
I find this a bit odd. You don't mention this addition in the commit message, and a quick look at the commits touching tlbflush.[ch] doesn't make the copyright assignment obvious (most commits originate from either SiFive or Christoph). In any way, please keep this kind of changes out of this series if possible, and have a separate discussion on who gets to brag about this code. Thanks, M. -- Without deviation from the norm, progress is not possible.