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References: <20220811120708.34912-1-imagedong@tencent.com>
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From:   Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>
Date:   Thu, 11 Aug 2022 16:34:29 +0200
Message-ID: <CANiq72=Eq1265hYhEVTGuh-_ZW+3HjWkwaktEfs7H7yPERfO0w@mail.gmail.com>
Subject: Re: [PATCH net-next] net: skb: prevent the split of
 kfree_skb_reason() by gcc
To:     menglong8.dong@gmail.com
Cc:     kuba@kernel.org, ojeda@kernel.org, ndesaulniers@google.com,
        davem@davemloft.net, edumazet@google.com, pabeni@redhat.com,
        asml.silence@gmail.com, imagedong@tencent.com,
        luiz.von.dentz@intel.com, vasily.averin@linux.dev,
        jk@codeconstruct.com.au, linux-kernel@vger.kernel.org,
        netdev@vger.kernel.org
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On Thu, Aug 11, 2022 at 2:07 PM <menglong8.dong@gmail.com> wrote:
>
> diff --git a/include/linux/compiler_attributes.h b/include/linux/compiler_attributes.h
> index 445e80517cab..51f7c13bca98 100644
> --- a/include/linux/compiler_attributes.h
> +++ b/include/linux/compiler_attributes.h
> @@ -371,4 +371,6 @@
>   */
>  #define __weak                          __attribute__((__weak__))
>
> +#define __nofnsplit                     __attribute__((optimize("O1")))
> +
>  #endif /* __LINUX_COMPILER_ATTRIBUTES_H */

Two notes on this: please use the double underscore form:
`__optimize__` and keep the file sorted (it should go after
`__overloadable__`, since we sort by the actual attribute name).

Thanks!

Cheers,
Miguel