Re: [PATCH v3 7/9] trace: use this_cpu_ptr per-cpu helper

[Shan Wei <shanwei88@gmail.com>]

Christoph Lameter said, at 2012/11/10 4:15:
> On Fri, 9 Nov 2012, Shan Wei wrote:
> 
>> -	return buffer->buffer;
>> +	return (char *)this_cpu_ptr(&percpu_buffer->buffer);
>>  }
> 
> Add a comment to explain the cast?

typeof(&buffer) is a pointer to array of 1024 char, or char (*)[1024].
But, typeof(&buffer[0]) is a pointer to char which match the return type of get_trace_buf().
As well-known, the value of &buffer is equal to &buffer[0].
so return this_cpu_ptr(&percpu_buffer->buffer[0]) can avoid this cast. 

I will submit v4 version patch which improve it.

Thanks~