linux-kernel - Re: [v3, 3/3] MIPS: VDSO: Add implementations of gettimeofday() and clock

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: <562FF15A.1050507@imgtec.com>
Date:	Tue, 27 Oct 2015 14:49:14 -0700
From:	Leonid Yegoshin <Leonid.Yegoshin@...tec.com>
To:	David Daney <ddaney.cavm@...il.com>
CC:	Ralf Baechle <ralf@...ux-mips.org>,
	Markos Chandras <markos.chandras@...tec.com>,
	<linux-mips@...ux-mips.org>, Alex Smith <alex.smith@...tec.com>,
	<linux-kernel@...r.kernel.org>
Subject: Re: [v3, 3/3] MIPS: VDSO: Add implementations of gettimeofday() and
 clock_gettime()


> For example, On OCTEON single-chip systems we synchronize the the 
> counters and they don't drift.  So, we can use CPO.Count. However, on 
> two-chip NUMA configurations there may be clock drift between the two 
> chips, so CPO.Count cannot be used as a clocksource.  We have a single 
> kernel image that runs on both types of systems, so we have to be able 
> to enable/disable the gettimeofday() acceleration.
>
Much more interesting the situation then there are a different clock 
frequency in different CPUs.

It seems for me that per-thread memory idea may be required soon.

- Leonid
--
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/