netdev - Re: [PATCH net V4 2/2] igb: offer a PTP Hardware Clock instead of the timecompare method

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]

Message-ID: <20120327183349.GB3878@netboy.at.omicron.at>
Date:	Tue, 27 Mar 2012 20:33:50 +0200
From:	Richard Cochran <richardcochran@...il.com>
To:	"Keller, Jacob E" <jacob.e.keller@...el.com>
Cc:	chetan loke <loke.chetan@...il.com>,
	"netdev@...r.kernel.org" <netdev@...r.kernel.org>,
	"e1000-devel@...ts.sourceforge.net" 
	<e1000-devel@...ts.sourceforge.net>,
	"Kirsher, Jeffrey T" <jeffrey.t.kirsher@...el.com>,
	"Ronciak, John" <john.ronciak@...el.com>,
	"john.stultz@...aro.org" <john.stultz@...aro.org>,
	"tglx@...utronix.de" <tglx@...utronix.de>
Subject: Re: [PATCH net V4 2/2] igb: offer a PTP Hardware Clock instead of
 the timecompare method

On Mon, Mar 26, 2012 at 08:51:28PM +0000, Keller, Jacob E wrote:
> 
> This is about a case where the user does something stupid. (runs the ioctls too
> fast). It appears that your answer is something like "The user did something
> stupid, we shouldn't care". My answer is, "we should do what we can to prevent
> this."

No matter how much you optimize your driver (or library or whatever),
there is always some user load that will kill your performance.

The locking is need for data integrity. The code path in the lock is
short. I doubt there is any serious performance issue here.

Richard
--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html