Re: 答复: 答复: [PATCH] ION: Sys_heap: fix the incorrect pool->gfp_mask setting

[Laura Abbott <labbott@redhat.com>]

On 01/10/2018 06:06 PM, Zengtao (B) wrote:
>> -----邮件原件-----
>> 发件人: Laura Abbott [mailto:labbott@redhat.com]
>> 发送时间: 2018年1月11日 8:01
>> 收件人: Zengtao (B) <prime.zeng@hisilicon.com>; Dan Carpenter
>> <dan.carpenter@oracle.com>; Chenfeng (puck) <puck.chen@hisilicon.com>
>> 抄送: sumit.semwal@linaro.org; gregkh@linuxfoundation.org;
>> arve@android.com; tkjos@android.com; maco@android.com;
>> devel@driverdev.osuosl.org; linux-kernel@vger.kernel.org
>> 主题: Re: 答复: [PATCH] ION: Sys_heap: fix the incorrect pool->gfp_mask
>> setting
>>
>> On 01/09/2018 04:06 AM, Zengtao (B) wrote:
>>>> -----邮件原件-----
>>>> 发件人: Dan Carpenter [mailto:dan.carpenter@oracle.com]
>>>> 发送时间: 2018年1月9日 17:14
>>>> 收件人: Chenfeng (puck) <puck.chen@hisilicon.com>
>>>> 抄送: Zengtao (B) <prime.zeng@hisilicon.com>; labbott@redhat.com;
>>>> sumit.semwal@linaro.org; gregkh@linuxfoundation.org;
>>>> arve@android.com; tkjos@android.com; maco@android.com;
>>>> devel@driverdev.osuosl.org; linux-kernel@vger.kernel.org
>>>> 主题: Re: [PATCH] ION: Sys_heap: fix the incorrect pool->gfp_mask
>>>> setting
>>>>
>>>> On Tue, Jan 09, 2018 at 11:30:09AM +0800, Chen Feng wrote:
>>>>>
>>>>>
>>>>> On 2018/1/9 18:43, Zeng Tao wrote:
>>>>>> This issue is introduced by the commit <e7f63771b60e> ("ION: Sys_heap:
>>>>>> Add cached pool to spead up cached buffer alloc"),
>>>>
>>>> Use the Fixes tag.
>>>>
>>>> Fixes: e7f63771b60e ("ION: Sys_heap: Add cached pool to spead up
>>>> cached buffer alloc")
>>>>
>>> Agree, thanks.
>>>
>>
>> If you're going to be fixing this, it would be good to fix the other problems
>> pointed out (stop with the #define of the flags).
>>
> It is OK, I will fix in the new version fix.
> 
> And to make the code more explicit, I have to choices of fixes:
> Choice 1:
> if (orders[i] > 4)
> 	gfp_flags = high_order_gfp_flags;
> else
> 	gfp_flags = low_order_gfp_flags;
> Choice 2:
> gfp_flags = (orders[i] > 4) ? high_order_gfp_flags : low_order_gfp_flags;
> 

I prefer #1, but please make sure you are following the
suggestions in https://marc.info/?l=linux-kernel&m=151518104214191&w=2

> Any suggestion ?
> 
> 
> BTW, I found another problem related:
> Currently the order 4 and order 0 allocation flag haven't got the __GFP_NOWARN set,
> if the order 4 allocation failed but the allocation of order 0 success, it will print warning
> message which is useless.
> 
> Of course, this is not related to this fix, but this is what I have met when test this fix.
> 

Yes, go ahead and fix that in a separate patch too.

> Thanks
> Zengtao
> 

Thanks,
Laura