linux-kernel - Re: [PATCH 3/3] lib: vsprintf: added a put

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]

Message-ID: <87y6cj791e.fsf@erwin.mina86.com>
Date:	Fri, 06 Aug 2010 22:58:37 +0200
From:	Michal Nazarewicz <mina86@...a86.com>
To:	Denys Vlasenko <vda.linux@...glemail.com>
Cc:	Michał Nazarewicz <m.nazarewicz@...sung.com>,
	linux-kernel@...r.kernel.org,
	"Douglas W. Jones" <jones@...uiowa.edu>,
	Andrew Morton <akpm@...ux-foundation.org>
Subject: Re: [PATCH 3/3] lib: vsprintf: added a put_dec() test and benchmark tool

Denys Vlasenko <vda.linux@...glemail.com> writes:

> On Friday 06 August 2010 10:34, Michał Nazarewicz wrote:
>> On Fri, 06 Aug 2010 07:10:06 +0200, Denys Vlasenko <vda.linux@...glemail.com> wrote:
>> 
>> > On Friday 06 August 2010 00:38, Michal Nazarewicz wrote:
>> >> This commit adds a test application for the put_dec() and
>> >> family of functions that are used by the previous two commits.
>> >>
>> >> Signed-off-by: Michal Nazarewicz <mina86@...a86.com>
>> >
>> >> +put-dec-test: put-dec-test.c
>> >> +	exec $(CC) $(CFLAGS) -o $@ $<
>> >
>> > (1) Why exec?
>> 
>> Micro Makefile optimisation -- saves us a fork().
>> 
>> I'll try to fix the benchmark over the weekend and will post updated
>> version.  Thanks for the comments.
>
> You might find some ideas in the attached file:
> * removed "correction" code
> * added verification of correctness for put_dec()
> * different rand64
>   (old one was giving same "random" number surprisingly often)
> * more robust coding in a few places

Thanks!  I actually changed the benchmark earlier today and redid all
benchmarks but I'll sure incorporate you're test code.

Also, I've removed rand_64() from my code in favour of reading random
data from /dev/urandom.  In consequence, all functions ale benchmarked
using the same values and it's still random (ie. no the same value all
the time).  This also made "correction" no longer needed.

It's 11pm here, so I'll try to send the new patches tomorrow morning
after getting some sleep.

Once again, thank you for all the comments and suggestiveness!

-- 
Best regards,                                         _     _
 .o. | Liege of Serenly Enlightened Majesty of      o' \,=./ `o
 ..o | Computer Science,  Michal "mina86" Nazarewicz   (o o)
 ooo +--<mina86-tlen.pl>--<jid:mina86-jabber.org>--ooO--(_)--Ooo--

Content of type "application/pgp-signature" skipped