| 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: Tue, 23 Sep 2008 14:02:08 -0700 From: "Martin Bligh" <mbligh@...gle.com> To: "Thomas Gleixner" <tglx@...utronix.de> Cc: "Masami Hiramatsu" <mhiramat@...hat.com>, "Linus Torvalds" <torvalds@...ux-foundation.org>, "Mathieu Desnoyers" <compudj@...stal.dyndns.org>, "Linux Kernel Mailing List" <linux-kernel@...r.kernel.org>, "Steven Rostedt" <rostedt@...dmis.org>, darren@...art.com, "Frank Ch. Eigler" <fche@...hat.com>, systemtap-ml <systemtap@...rces.redhat.com> Subject: Re: Unified tracing buffer >> I think the tolerance is about 500 cycles. If that's not sufficient, I guess >> we'll have to either live with some slight misordering (which people have >> pointed out is kind of inevitable anyway) on these broken machines? >> It was sufficient for what we were using it for, but maybe not for everyone. > > Well, I dont care about the trace reordering at all. I care about user > space visible time going backwards issues observed via the > gettimeofday vsyscall. 500 cycles should be fine, I doubt that we can > migrate in less than that :) Right, that's what we were interested in. > I guess you try this only for machines where the TSC runs with > constant frequency, right ? We don't do DVFS on the 'broken' TSC machines, just halt. But yes, it's selective -- 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