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

Zengtao (B) prime.zeng at hisilicon.com
Thu Jan 11 02:06:09 UTC 2018


>-----邮件原件-----
>发件人: Laura Abbott [mailto:labbott at redhat.com]
>发送时间: 2018年1月11日 8:01
>收件人: Zengtao (B) <prime.zeng at hisilicon.com>; Dan Carpenter
><dan.carpenter at oracle.com>; Chenfeng (puck) <puck.chen at hisilicon.com>
>抄送: sumit.semwal at linaro.org; gregkh at linuxfoundation.org;
>arve at android.com; tkjos at android.com; maco at android.com;
>devel at driverdev.osuosl.org; linux-kernel at 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 at oracle.com]
>>> 发送时间: 2018年1月9日 17:14
>>> 收件人: Chenfeng (puck) <puck.chen at hisilicon.com>
>>> 抄送: Zengtao (B) <prime.zeng at hisilicon.com>; labbott at redhat.com;
>>> sumit.semwal at linaro.org; gregkh at linuxfoundation.org;
>>> arve at android.com; tkjos at android.com; maco at android.com;
>>> devel at driverdev.osuosl.org; linux-kernel at 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;

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.

Thanks
Zengtao 


More information about the devel mailing list