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Subject: Re: [PATCH V4] mlx4_core: allocate ICM memory in page size chunks
To:     Michal Hocko <mhocko@kernel.org>,
        Eric Dumazet <eric.dumazet@gmail.com>
Cc:     David Miller <davem@davemloft.net>, qing.huang@oracle.com,
        tariqt@mellanox.com, haakon.bugge@oracle.com,
        yanjun.zhu@oracle.com, netdev@vger.kernel.org,
        linux-rdma@vger.kernel.org, linux-kernel@vger.kernel.org,
        gi-oh.kim@profitbricks.com
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 <20180531065405.GH15278@dhcp22.suse.cz>
From:   Eric Dumazet <eric.dumazet@gmail.com>
Message-ID: <ae114f01-4b09-bb1c-fb92-6152486a896f@gmail.com>
Date:   Thu, 31 May 2018 04:35:31 -0400
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On 05/31/2018 02:54 AM, Michal Hocko wrote:
> On Tue 29-05-18 23:49:59, Eric Dumazet wrote:
>>
>>
>> On 05/29/2018 11:44 PM, Eric Dumazet wrote:
>>
>>>
>>> And I will add this simple fix, this really should address your initial concern much better.
>>>
>>> @@ -99,6 +100,8 @@ static int mlx4_alloc_icm_pages(struct scatterlist *mem, int order,
>>>  {
>>>         struct page *page;
>>>  
>>> +       if (order)
>>> +               gfp_mask |= __GFP_NORETRY;
>>
>>     and also      gfp_mask &= ~__GFP_DIRECT_RECLAIM
> 
> JFTR the latter one makes __GFP_NORETRY pointless. Non sleeping allocations
> are not retrying.

Hi Michal

Since when this rule is applied ?

These GFP flags change all the time, I suggest mm experts to cleanup existing call sites ?

I merely copied/pasted from alloc_skb_with_frags() :/

Thanks !