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Message-ID: <27c8af2f-c931-4d36-9db9-112de79ec3cd@bytedance.com>
Date: Mon, 18 Dec 2023 19:54:54 +0800
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Subject: Re: [PATCH v2 6/6] mm/zswap: directly use percpu mutex and buffer in
 load/store
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To: Yosry Ahmed <yosryahmed@google.com>
Cc: Seth Jennings <sjenning@redhat.com>, Dan Streetman <ddstreet@ieee.org>,
 Chris Li <chriscli@google.com>, Nhat Pham <nphamcs@gmail.com>,
 Vitaly Wool <vitaly.wool@konsulko.com>,
 Andrew Morton <akpm@linux-foundation.org>,
 Johannes Weiner <hannes@cmpxchg.org>, linux-kernel@vger.kernel.org,
 linux-mm@kvack.org, Chris Li <chrisl@kernel.org>
References: <20231213-zswap-dstmem-v2-0-daa5d9ae41a7@bytedance.com>
 <20231213-zswap-dstmem-v2-6-daa5d9ae41a7@bytedance.com>
 <CAJD7tkZSrd-R-vuVqh29fgZ6bmo3EJxdb2Eahm0Ozg5hkPEjRg@mail.gmail.com>
From: Chengming Zhou <zhouchengming@bytedance.com>
In-Reply-To: <CAJD7tkZSrd-R-vuVqh29fgZ6bmo3EJxdb2Eahm0Ozg5hkPEjRg@mail.gmail.com>
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On 2023/12/18 17:37, Yosry Ahmed wrote:
> On Mon, Dec 18, 2023 at 12:22 AM Chengming Zhou
> <zhouchengming@bytedance.com> wrote:
>>
>> Since the introduce of reusing the dstmem in the load path, it seems
>> confusing that we are now using acomp_ctx->dstmem and acomp_ctx->mutex
>> now for purposes other than what the naming suggests.
>>
>> Yosry suggested removing these two fields from acomp_ctx, and directly
>> using zswap_dstmem and zswap_mutex in both the load and store paths,
>> rename them, and add proper comments above their definitions that they
>> are for generic percpu buffering on the load and store paths.
>>
>> So this patch remove dstmem and mutex from acomp_ctx, and rename the
>> zswap_dstmem to zswap_buffer, using the percpu mutex and buffer on
>> the load and store paths. And refactor out __zswap_store() to only
>> include the compress & store, since I found zswap_store() is too long.
> 
> I am not sure refactoring out __zswap_store() is useful to be honest,
> but I am not objecting to it, it mirrors __zswap_load() in a sense.
> However, if you want to do so, please do it in a separate patch from
> renaming the percpu buffers and mutex. This will make reviewing easier
> (and make my Suggested-by correctly scoped).
> 

After thinking twice, I dropped the __zswap_store() part. Right, it's
not much useful.

Thanks.