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
| ||
|
Date: Mon, 10 Feb 2014 22:14:58 +0100 From: Peter Zijlstra <peterz@...radead.org> To: Chris Metcalf <cmetcalf@...era.com> Cc: Linux Kernel Mailing List <linux-kernel@...r.kernel.org> Subject: Re: [RFC][PATCH 0/5] arch: atomic rework On Mon, Feb 10, 2014 at 04:08:11PM -0500, Chris Metcalf wrote: > (+LKML again) > > On 2/10/2014 3:57 PM, Peter Zijlstra wrote: > > On Mon, Feb 10, 2014 at 03:50:04PM -0500, Chris Metcalf wrote: > >> On 2/6/2014 8:52 AM, Peter Zijlstra wrote: > >>> Its been compiled on everything I have a compiler for, however frv and > >>> tile are missing because they're special and I was tired. > >> So what's the specialness on tile? > > Its not doing the atomic work in ASM but uses magic builtins or such. > > > > I got the list of magic funcs for tilegx, but didn't look into the 32bit > > chips. > > Oh, I see. The <asm/atomic.h> files on tile are already reasonably well-factored. > > It's possible you could do better, but I think not by too much, other than possibly > by using <asm-generic/atomic.h> for some of the common idioms like "subtraction > is addition with a negative second argument", etc., which hasn't been done elsewhere. The last patch 5/5 adds a few atomic ops; I could of course use cmpxchg() loops for everything, but I found tilegx actually has fetch_or and fetch_and to implement atomic_or() / atomic_and(). It doesn't have fetch_xor() from what I've been told so atomic_xor() will have to become a cmpxchg() loop. -- 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