| 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: Sun, 13 Apr 2008 09:05:13 +0200 From: Ingo Molnar <mingo@...e.hu> To: Peter Zijlstra <peterz@...radead.org> Cc: Matthew Wilcox <matthew@....cx>, linux-kernel@...r.kernel.org, Linus Torvalds <torvalds@...l.org> Subject: Re: [PATCH] Replace completions with semaphores * Peter Zijlstra <peterz@...radead.org> wrote: > On Fri, 2008-04-11 at 15:00 -0600, Matthew Wilcox wrote: > > > So does it make sense to retain the completion as a primitive in > > Linux? > > My take on it is the opposite: kill off semaphores and leave the > completions around. exactly. I first misread the subject line because i parsed it as "replace semaphores with completions" and i thought "cool", then did i realize that the patch does it the other way around. Converting completions to semaphores just makes no sense. Besides all your arguments later in this thread about how problematic locking primitives semaphores are because they are so vague (which are all correct), there's also another aspect: completions are faster a bit in theory, because they know that they will schedule most of the time - while semaphores assume that they will _not_ schedule. (And that's exactly because the intent of the developer when using a completion is crystal clear.) Ingo -- 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