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From:   Zhongkun He <hezhongkun.hzk@bytedance.com>
Date:   Fri, 17 Nov 2023 17:56:00 +0800
Message-ID: <CACSyD1NJ4ycr74pXHNus3ZjA=LvZP+aMNyz=iWyHuDODpx7aww@mail.gmail.com>
Subject: Re: [External] Re: [PATCH] mm:zswap: fix zswap entry reclamation
 failure in two scenarios
To:     Chris Li <chriscli@google.com>
Cc:     Yosry Ahmed <yosryahmed@google.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Johannes Weiner <hannes@cmpxchg.org>,
        Nhat Pham <nphamcs@gmail.com>,
        Seth Jennings <sjenning@redhat.com>,
        Dan Streetman <ddstreet@ieee.org>,
        Vitaly Wool <vitaly.wool@konsulko.com>,
        linux-mm <linux-mm@kvack.org>,
        LKML <linux-kernel@vger.kernel.org>, Ying <ying.huang@intel.com>
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>
> That will cancel the batching effect on the swap slot free, making the
> common case for  swapping  faults take longer to complete, righ?
> If I recall correctly, the uncharge is the expensive part of the swap
> slot free operation.
> I just want to figure out what we are trading off against. This is not
> one side wins all situations.
>

Hi Chris, thanks for your feedback.  I have the same concerns,
maybe we should just move the zswap_invalidate() out of batches,
as Yosry mentioned above.