linux-kernel - Re: [cpuops cmpxchg double V2 1/4] Generic support for this_cpu_cmpxchg

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:	Fri, 21 Jan 2011 14:32:40 -0500
From:	Mathieu Desnoyers <mathieu.desnoyers@...icios.com>
To:	Tejun Heo <tj@...nel.org>
Cc:	"H. Peter Anvin" <hpa@...or.com>,
	Pekka Enberg <penberg@...helsinki.fi>,
	Christoph Lameter <cl@...ux.com>, akpm@...ux-foundation.org,
	linux-kernel@...r.kernel.org, Eric Dumazet <eric.dumazet@...il.com>
Subject: Re: [cpuops cmpxchg double V2 1/4] Generic support for
	this_cpu_cmpxchg_double

* Tejun Heo (tj@...nel.org) wrote:
[...]
> > (note: packed here along with "aligned" does _not_ generate ugly
> > bytewise read/write memory ops like "packed" alone. The use of
> > "packed" is to let the compiler down-align the structure to the
> > value requested, instead of uselessly aligning it on 32-byte if it
> > chooses to.)
> 
> Yeah, good point.  :-)

For the records, I just noticed that "packed, aligned(8)" can generate unaligned
accesses on sparc64 by removing the padding between a "int" and a following
pointer. So we should not use it.

Thanks,

Mathieu

-- 
Mathieu Desnoyers
Operating System Efficiency R&D Consultant
EfficiOS Inc.
http://www.efficios.com
--
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/