Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
MIME-Version: 1.0
References: <20210510093753.40683-1-mark.rutland@arm.com> <20210510093753.40683-17-mark.rutland@arm.com>
In-Reply-To: <20210510093753.40683-17-mark.rutland@arm.com>
From:   Guo Ren <guoren@kernel.org>
Date:   Mon, 10 May 2021 21:27:10 +0800
Message-ID: <CAJF2gTSwzb9rOvuubgz0PNeweOVQ_94mqDXyTfdprVZDcEp+FA@mail.gmail.com>
Subject: Re: [PATCH 16/33] locking/atomic: csky: move to ARCH_ATOMIC
To:     Mark Rutland <mark.rutland@arm.com>
Cc:     Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Will Deacon <will@kernel.org>, boqun.feng@gmail.com,
        Peter Zijlstra <peterz@infradead.org>,
        Albert Ou <aou@eecs.berkeley.edu>,
        Arnd Bergmann <arnd@arndb.de>,
        Brian Cain <bcain@codeaurora.org>,
        Benjamin Herrenschmidt <benh@kernel.crashing.org>,
        Chris Zankel <chris@zankel.net>, Rich Felker <dalias@libc.org>,
        David Miller <davem@davemloft.net>,
        Vincent Chen <deanbo422@gmail.com>,
        Helge Deller <deller@gmx.de>,
        Geert Uytterhoeven <geert@linux-m68k.org>,
        Greentime Hu <green.hu@gmail.com>,
        Ivan Kokshaysky <ink@jurassic.park.msu.ru>,
        "James E.J. Bottomley" <James.Bottomley@hansenpartnership.com>,
        Max Filippov <jcmvbkbc@gmail.com>,
        Jonas Bonn <jonas@southpole.se>,
        Ley Foon Tan <ley.foon.tan@intel.com>,
        Russell King <linux@armlinux.org.uk>,
        Matt Turner <mattst88@gmail.com>,
        Michal Simek <monstr@monstr.eu>,
        Michael Ellerman <mpe@ellerman.id.au>,
        Nick Hu <nickhu@andestech.com>,
        Palmer Dabbelt <palmer@dabbelt.com>,
        Paul Mackerras <paulus@samba.org>,
        Paul Walmsley <paul.walmsley@sifive.com>,
        Richard Henderson <rth@twiddle.net>,
        Stafford Horne <shorne@gmail.com>,
        Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>,
        Thomas Bogendoerfer <tsbogend@alpha.franken.de>,
        Vineet Gupta <vgupta@synopsys.com>,
        Yoshinori Sato <ysato@users.sourceforge.jp>
Content-Type: text/plain; charset="UTF-8"
Precedence: bulk

On Mon, May 10, 2021 at 5:41 PM Mark Rutland <mark.rutland@arm.com> wrote:
>
> We'd like all architectures to convert to ARCH_ATOMIC, as once all
> architectures are converted it will be possible to make significant
> cleanups to the atomics headers, and this will make it much easier to
> generically enable atomic functionality (e.g. debug logic in the
> instrumented wrappers).
>
> As a step towards that, this patch migrates csky to ARCH_ATOMIC. The
> arch code provides arch_{atomic,atomic64,xchg,cmpxchg}*(), and common
> code wraps these with optional instrumentation to provide the regular
> functions.
>
> Signed-off-by: Mark Rutland <mark.rutland@arm.com>
> Cc: Boqun Feng <boqun.feng@gmail.com>
> Cc: Guo Ren <guoren@kernel.org>
> Cc: Peter Zijlstra <peterz@infradead.org>
> Cc: Will Deacon <will@kernel.org>
> ---
>  arch/csky/Kconfig               | 1 +
>  arch/csky/include/asm/cmpxchg.h | 8 ++++----
>  2 files changed, 5 insertions(+), 4 deletions(-)
>
> diff --git a/arch/csky/Kconfig b/arch/csky/Kconfig
> index 8de5b987edb9..3521f14bcd96 100644
> --- a/arch/csky/Kconfig
> +++ b/arch/csky/Kconfig
> @@ -2,6 +2,7 @@
>  config CSKY
>         def_bool y
>         select ARCH_32BIT_OFF_T
> +       select ARCH_ATOMIC
>         select ARCH_HAS_DMA_PREP_COHERENT
>         select ARCH_HAS_GCOV_PROFILE_ALL
>         select ARCH_HAS_SYNC_DMA_FOR_CPU
> diff --git a/arch/csky/include/asm/cmpxchg.h b/arch/csky/include/asm/cmpxchg.h
> index dabc8e46ce7b..d1bef11f8dc9 100644
> --- a/arch/csky/include/asm/cmpxchg.h
> +++ b/arch/csky/include/asm/cmpxchg.h
> @@ -31,7 +31,7 @@ extern void __bad_xchg(void);
>         __ret;                                                  \
>  })
>
> -#define xchg_relaxed(ptr, x) \
> +#define arch_xchg_relaxed(ptr, x) \
>                 (__xchg_relaxed((x), (ptr), sizeof(*(ptr))))
>
>  #define __cmpxchg_relaxed(ptr, old, new, size)                 \
> @@ -61,14 +61,14 @@ extern void __bad_xchg(void);
>         __ret;                                                  \
>  })
>
> -#define cmpxchg_relaxed(ptr, o, n) \
> +#define arch_cmpxchg_relaxed(ptr, o, n) \
>         (__cmpxchg_relaxed((ptr), (o), (n), sizeof(*(ptr))))
>
> -#define cmpxchg(ptr, o, n)                                     \
> +#define arch_cmpxchg(ptr, o, n)                                \
>  ({                                                             \
>         __typeof__(*(ptr)) __ret;                               \
>         __smp_release_fence();                                  \
> -       __ret = cmpxchg_relaxed(ptr, o, n);                     \
> +       __ret = arch_cmpxchg_relaxed(ptr, o, n);                \
>         __smp_acquire_fence();                                  \
>         __ret;                                                  \
>  })
> --
> 2.11.0
>
Acked-by: Guo Ren <guoren@kernel.org>

-- 
Best Regards
 Guo Ren

ML: https://lore.kernel.org/linux-csky/