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Date:   Wed, 13 Apr 2022 23:46:00 +0800
From:   Boqun Feng <boqun.feng@gmail.com>
To:     guoren@kernel.org
Cc:     arnd@arndb.de, palmer@dabbelt.com, mark.rutland@arm.com,
        will@kernel.org, peterz@infradead.org, linux-arch@vger.kernel.org,
        linux-kernel@vger.kernel.org, linux-riscv@lists.infradead.org,
        Guo Ren <guoren@linux.alibaba.com>,
        Andrea Parri <parri.andrea@gmail.com>
Subject: Re: [PATCH V2 0/3] riscv: atomic: Optimize AMO instructions usage
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References: <20220412034957.1481088-1-guoren@kernel.org>
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[Cc Andrea]

On Tue, Apr 12, 2022 at 11:49:54AM +0800, guoren@kernel.org wrote:
> From: Guo Ren <guoren@linux.alibaba.com>
>=20
> These patch series contain one cleanup and some optimizations for
> atomic operations.
>=20

Seems to me that you are basically reverting 5ce6c1f3535f
("riscv/atomic: Strengthen implementations with fences"). That commit
fixed an memory ordering issue, could you explain why the issue no
longer needs a fix?

Regards,
Boqun

> Changes in V2:
>  - Fixup LR/SC memory barrier semantic problems which pointed by
>    Rutland
>  - Combine patches into one patchset series
>  - Separate AMO optimization & LRSC optimization for convenience
>    patch review
>=20
> Guo Ren (3):
>   riscv: atomic: Cleanup unnecessary definition
>   riscv: atomic: Optimize acquire and release for AMO operations
>   riscv: atomic: Optimize memory barrier semantics of LRSC-pairs
>=20
>  arch/riscv/include/asm/atomic.h  | 70 ++++++++++++++++++++++++++++++--
>  arch/riscv/include/asm/cmpxchg.h | 42 +++++--------------
>  2 files changed, 76 insertions(+), 36 deletions(-)
>=20
> --=20
> 2.25.1
>=20

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