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Date:   Sat, 12 Aug 2023 10:39:13 +0530
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Subject: Re: [PATCH] Multi-gen LRU: skip CMA pages when they are not eligible
To:     Yu Zhao <yuzhao@google.com>
CC:     David Hildenbrand <david@redhat.com>, <akpm@linux-foundation.org>,
        <zhaoyang.huang@unisoc.com>, <surenb@google.com>,
        <linux-mm@kvack.org>, <linux-kernel@vger.kernel.org>,
        Kalesh Singh <kaleshsingh@google.com>
References: <1691568344-13475-1-git-send-email-quic_charante@quicinc.com>
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From:   Charan Teja Kalla <quic_charante@quicinc.com>
In-Reply-To: <CAOUHufarW3utTCqk+tes-tbU7iRKCYa_GMZvSNxJrFRKWXMbWw@mail.gmail.com>
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On 8/9/2023 10:39 PM, Yu Zhao wrote:
>> On Wed, Aug 9, 2023 at 7:00 AM David Hildenbrand <david@redhat.com> wrote:
>>> On 09.08.23 10:05, Charan Teja Kalla wrote:
>>>> This patch is based on the commit 5da226dbfce3("mm: skip CMA pages when
>>>> they are not available") which skips cma pages reclaim when they are not
>>>> eligible for the current allocation context. In mglru, such pages are
>>>> added to the tail of the immediate generation to maintain better LRU
>>>> order, which is unlike the case of conventional LRU where such pages are
>>>> directly added to the head of the LRU list(akin to adding to head of the
>>>> youngest generation in mglru).
>>>>
>>>> No observable issue without this patch on MGLRU, but logically it make
>>>> sense to skip the CMA page reclaim when those pages can't be satisfied
>>>> for the current allocation context.
>>>>
>>>> Signed-off-by: Charan Teja Kalla <quic_charante@quicinc.com>
>> Reviewed-by: Kalesh Singh <kaleshsingh@google.com>
> Thanks, Charan! Do we need a "Fixes" tag?
I think the below tag matches.

Fixes: ac35a4902374 ("mm: multi-gen LRU: minimal implementation")
>