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Message-ID: <ec1c4922-bb04-7896-8864-98cd96c9b0fc@gmail.com>
Date:   Wed, 14 Jun 2023 19:10:31 +0800
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Subject: Re: [PATCH v2 0/3] Optimize the fast path of mas_store()
To:     "Liam R. Howlett" <Liam.Howlett@Oracle.com>
References: <20230609120347.63936-1-zhangpeng.00@bytedance.com>
 <20230613172352.u4oj5ydoloztvdqk@revolver>
Cc:     Peng Zhang <zhangpeng.00@bytedance.com>, akpm@linux-foundation.org,
        linux-mm@kvack.org, linux-kernel@vger.kernel.org,
        maple-tree@lists.infradead.org
From:   Peng Zhang <perlyzhang@gmail.com>
In-Reply-To: <20230613172352.u4oj5ydoloztvdqk@revolver>
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在 2023/6/14 01:23, Liam R. Howlett 写道:
> * Peng Zhang <zhangpeng.00@bytedance.com> [230609 08:04]:
>> Add fast paths for mas_wr_append() and mas_wr_slot_store() respectively.
>> The newly added fast path of mas_wr_append() is used in fork() and how
>> much it benefits fork() depends on how many VMAs are duplicated.
>>
>> Changes since v1:
>>   - Revise comment and commit log. [3/3]
>>   - Add test for mas_wr_modify() fast path. [1/3]
> 
> Thanks for adding the tests.  I'm just trying to figure out how to best
> address testing this in RCU mode. And by testing it I mean add tests in
> RCU that does this and detect the failure by modifying your code, then
> change it back and have it pass the test by falling back to node store.
> This would need to change tools/testing/radix-tree/maple.c to update the
> testing there.
I see what you mean now, I will try to make a test in RCU mode.
> 
>>
>> v1: https://lore.kernel.org/lkml/20230602075353.5917-1-zhangpeng.00@bytedance.com/
>>
>> Peng Zhang (3):
>>    maple_tree: add test for mas_wr_modify() fast path
>>    maple_tree: optimize mas_wr_append(), also improve duplicating VMAs
>>    maple_tree: add a fast path case in mas_wr_slot_store()
>>
>>   lib/maple_tree.c      | 69 ++++++++++++++++++++++++++++---------------
>>   lib/test_maple_tree.c | 65 ++++++++++++++++++++++++++++++++++++++++
>>   2 files changed, 111 insertions(+), 23 deletions(-)
>>
>> -- 
>> 2.20.1
>>
>