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] [thread-next>] [day] [month] [year] [list]
Date:	Tue, 20 Dec 2011 14:19:54 +0400
From:	Glauber Costa <glommer@...allels.com>
To:	Peter Zijlstra <peterz@...radead.org>
CC:	Martin Schwidefsky <schwidefsky@...ibm.com>,
	Ingo Molnar <mingo@...e.hu>,
	Stephen Rothwell <sfr@...b.auug.org.au>,
	Thomas Gleixner <tglx@...utronix.de>,
	"H. Peter Anvin" <hpa@...or.com>, <linux-next@...r.kernel.org>,
	<linux-kernel@...r.kernel.org>
Subject: Re: linux-next: manual merge of the tip tree with the cputime tree

On 12/19/2011 06:08 PM, Peter Zijlstra wrote:
> On Mon, 2011-12-19 at 13:31 +0100, Martin Schwidefsky wrote:
>> Just one question: are you sure that you want the cpustat array
>> to be u64 instead of cputime64_t? The content of the cpustat array is defined
>> by the architecture semantics of cputime64_t, for CONFIG_VIRT_CPU_ACCOUNTING=y
>> this is not a jiffy counter. If the array is u64 we won't get the sparse
>> checking when reading from cpustat.
>
> So as Glauber said the reason was that we wanted to use simply
> operators, and IIRC he wanted to add a few fields that had to be u64.
>
> I'm not sure what the current plans are wrt adding more fields, but with
> your work cputime_t should again be a simple type and thus regular math
> operators should work again, right?
>
> Glauber, do you still need to add fields?

Due to the current state of discussions of cpu vs cpuacct, I think the 
final state of this is quite unclear. However, I think Martin's work is
a quite worthwhile piece for us to have. So last case we can add extra 
fields in a different array and tell them apart by the index, etc. It 
shouldn't be expensive at all.


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Powered by blists - more mailing lists