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Subject: Re: [PATCH net-next v7] net/core: Introduce netdev_core_stats_inc()
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To: Eric Dumazet <edumazet@google.com>
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From: Yajun Deng <yajun.deng@linux.dev>
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On 2023/10/9 15:53, Eric Dumazet wrote:
> On Mon, Oct 9, 2023 at 5:07 AM Yajun Deng <yajun.deng@linux.dev> wrote:
>
>> 'this_cpu_read + this_cpu_write' and 'pr_info + this_cpu_inc' will make
>> the trace work well.
>>
>> They all have 'pop' instructions in them. This may be the key to making
>> the trace work well.
>>
>> Hi all,
>>
>> I need your help on percpu and ftrace.
>>
> I do not think you made sure netdev_core_stats_inc() was never inlined.
>
> Adding more code in it is simply changing how the compiler decides to
> inline or not.


Yes, you are right. It needs to add the 'noinline' prefix. The 
disassembly code will have 'pop'

instruction.

Thanks.