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Message-ID: <66b3f3ec-7146-4763-bd51-bb48ebb4ba95@bytedance.com>
Date: Tue, 19 Dec 2023 22:07:58 +0800
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Subject: Re: [PATCH v3 4/6] mm/zswap: cleanup zswap_load()
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To: Chris Li <chrisl@kernel.org>
Cc: Seth Jennings <sjenning@redhat.com>, Yosry Ahmed <yosryahmed@google.com>,
 Vitaly Wool <vitaly.wool@konsulko.com>, Dan Streetman <ddstreet@ieee.org>,
 Johannes Weiner <hannes@cmpxchg.org>,
 Andrew Morton <akpm@linux-foundation.org>, Nhat Pham <nphamcs@gmail.com>,
 linux-kernel@vger.kernel.org, linux-mm@kvack.org
References: <20231213-zswap-dstmem-v3-0-4eac09b94ece@bytedance.com>
 <20231213-zswap-dstmem-v3-4-4eac09b94ece@bytedance.com>
 <CAF8kJuOnBhVRcC9bPJrqSDQYynbG+CpJDveFn9MJNmsBsFyM+g@mail.gmail.com>
From: Chengming Zhou <zhouchengming@bytedance.com>
In-Reply-To: <CAF8kJuOnBhVRcC9bPJrqSDQYynbG+CpJDveFn9MJNmsBsFyM+g@mail.gmail.com>
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On 2023/12/19 20:47, Chris Li wrote:
> On Mon, Dec 18, 2023 at 3:50 AM Chengming Zhou
> <zhouchengming@bytedance.com> wrote:
>>
>> After the common decompress part goes to __zswap_load(), we can cleanup
>> the zswap_load() a little.
>>
>> Reviewed-by: Yosry Ahmed <yosryahmed@google.com>
>> Signed-off-by: Chengming Zhou <zhouchengming@bytedance.com>
>> ---
>>  mm/zswap.c | 12 ++++--------
>>  1 file changed, 4 insertions(+), 8 deletions(-)
>>
>> diff --git a/mm/zswap.c b/mm/zswap.c
>> index 3433bd6b3cef..86886276cb81 100644
>> --- a/mm/zswap.c
>> +++ b/mm/zswap.c
>> @@ -1759,7 +1759,6 @@ bool zswap_load(struct folio *folio)
>>         struct zswap_tree *tree = zswap_trees[type];
>>         struct zswap_entry *entry;
>>         u8 *dst;
>> -       bool ret;
>>
>>         VM_WARN_ON_ONCE(!folio_test_locked(folio));
>>
>> @@ -1776,19 +1775,16 @@ bool zswap_load(struct folio *folio)
>>                 dst = kmap_local_page(page);
>>                 zswap_fill_page(dst, entry->value);
>>                 kunmap_local(dst);
>> -               ret = true;
>> -               goto stats;
>> +       } else {
>> +               __zswap_load(entry, page);
> 
> Very minor nitpick. I think this change you only take out the "ret",
> you don't have to remove the goto. Personally I prefer the one with
> the goto because If (!entry->length) is a rare case, having them
> indented match the normal execution flow is the streamlined one
> without indentation.
> 
> If you keep the else statement without the goto. You can move
> __zswap_load(entry,page) to the if statement so most common case go
> through the if statement rather than else.

Make sense. I will change if a new version is needed.

> 
> I also think this commit can fold into the previous one. As I said,
> this is minor comment, it is your call.
> 
> Acked-by: Chis Li <chrisl@kernel.org> (Google)

Thanks for review!