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Date: Fri, 20 Mar 2015 12:05:34 +0800
From: Xie XiuQi <xiexiuqi@huawei.com>
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To: Steven Rostedt <rostedt@goodmis.org>
CC: Borislav Petkov <bp@suse.de>, <akpm@linux-foundation.org>,
        <n-horiguchi@ah.jp.nec.com>, <gong.chen@linux.intel.com>,
        <bhelgaas@google.com>, <tony.luck@intel.com>,
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Subject: Re: [PATCH] trace, RAS: remove unnecessary const
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On 2015/3/19 21:00, Steven Rostedt wrote:
> On Thu, 19 Mar 2015 19:57:17 +0800
> Xie XiuQi <xiexiuqi@huawei.com> wrote:
> 
>> On 2015/3/19 18:33, Borislav Petkov wrote:
>>> On Thu, Mar 19, 2015 at 04:50:04PM +0800, Xie XiuQi wrote:
>>>> These parameters are passed by value. There's no need to make them const.
>>>
>>> I can think of a reason:
>>>
>>> include/trace/../../include/ras/ras_event.h: In function ‘ftrace_raw_event_mc_event’:
>>> include/trace/../../include/ras/ras_event.h:136:35: error: assignment of read-only parameter ‘top_layer’
>>>    __entry->top_layer  = top_layer = 12;
>>
>> Oh, indeed. Thanks, Boris!
>>
> 
> Don't get too excited about that answer. If this is indeed the case,
> then all functions with parameters that do not get modify later should
> be set to const. Do we really want that? And how does this fix:
> 
> 	__entry->top_layer = 12;

Yes, I agree. I've retrieved the entire kernel source tree, and did not find
elsewhere such usage. Both sounds reasonable. Now, I've no idea about this patch.

Thanks Steve and Boris!

--
Xie XiuQi

> 
> -- Steve
> 
> .
>