linux-kernel - Re: [PATCH v3] pipe: use __pipe_{lock,unlock} instead of spinlock

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Date:   Sat, 7 Jan 2023 11:31:38 +0800
From:   Hongchen Zhang <zhanghongchen@...ngson.cn>
To:     sedat.dilek@...il.com, Luis Chamberlain <mcgrof@...nel.org>
Cc:     Alexander Viro <viro@...iv.linux.org.uk>,
        Andrew Morton <akpm@...ux-foundation.org>,
        Kuniyuki Iwashima <kuniyu@...zon.co.jp>,
        David Howells <dhowells@...hat.com>,
        Christophe JAILLET <christophe.jaillet@...adoo.fr>,
        Randy Dunlap <rdunlap@...radead.org>,
        Eric Dumazet <edumazet@...gle.com>,
        linux-fsdevel@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH v3] pipe: use __pipe_{lock,unlock} instead of spinlock

Hi Sedat,

On 2023/1/7 am 4:33, Sedat Dilek wrote:
> On Fri, Jan 6, 2023 at 8:40 PM Luis Chamberlain <mcgrof@...nel.org> wrote:
>>
>> On Fri, Jan 06, 2023 at 05:48:44PM +0800, Hongchen Zhang wrote:
>>> Use spinlock in pipe_read/write cost too much time,IMO
>>> pipe->{head,tail} can be protected by __pipe_{lock,unlock}.
>>> On the other hand, we can use __pipe_{lock,unlock} to protect
>>> the pipe->{head,tail} in pipe_resize_ring and
>>> post_one_notification.
>>>
>>> I tested this patch using UnixBench's pipe test case on a x86_64
>>> machine,and get the following data:
>>> 1) before this patch
>>> System Benchmarks Partial Index  BASELINE       RESULT    INDEX
>>> Pipe Throughput                   12440.0     493023.3    396.3
>>>                                                          ========
>>> System Benchmarks Index Score (Partial Only)              396.3
>>>
>>> 2) after this patch
>>> System Benchmarks Partial Index  BASELINE       RESULT    INDEX
>>> Pipe Throughput                   12440.0     507551.4    408.0
>>>                                                          ========
>>> System Benchmarks Index Score (Partial Only)              408.0
>>>
>>> so we get ~3% speedup.
>>>
>>> Signed-off-by: Hongchen Zhang <zhanghongchen@...ngson.cn>
>>> ---
>>
>> After the above "---" line you should have the changlog descrption.
>> For instance:
>>
>> v3:
>>    - fixes bleh blah blah
>> v2:
>>    - fixes 0-day report by ... etc..
>>    - fixes spelling or whatever
>>
>> I cannot decipher what you did here differently, not do I want to go
>> looking and diff'ing. So you are making the life of reviewer harder.
>>
> 
> Happy new 2023.
> 
> Positive wording... You can make reviewers' life easy when...
> (encourage people).
> Life is easy, people live hard.
> 
> +1 Adding ChangeLog of patch history
> 
> Cannot say...
> Might be good to add the link to Linus test-case + your results in the
> commit message as well?
> 
> ...
> Link: https://git.kernel.org/linus/0ddad21d3e99 (test-case of Linus
> suggested-by Andrew)
> ...
> Signed-off-by: Hongchen Zhang <zhanghongchen@...ngson.cn>
> ...
> 
> Thanks.
> 
> Best regards,
> -Sedat-
> 

OK, I have send a new v3 patch with these messages in commit message, 
Please help to check and review again.

Best Regards,
Hongchen Zhang