From: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
To: David Daney <ddaney.cavm@gmail.com>
Cc: Ralf Baechle <ralf@linux-mips.org>,
Markos Chandras <markos.chandras@imgtec.com>,
<linux-mips@linux-mips.org>, Alex Smith <alex.smith@imgtec.com>,
<linux-kernel@vger.kernel.org>
Subject: Re: [v3, 3/3] MIPS: VDSO: Add implementations of gettimeofday() and clock_gettime()
Date: Tue, 27 Oct 2015 14:49:14 -0700 [thread overview]
Message-ID: <562FF15A.1050507@imgtec.com> (raw)
In-Reply-To: <562FF05A.508@gmail.com>
> 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
WARNING: multiple messages have this Message-ID (diff)
From: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
To: David Daney <ddaney.cavm@gmail.com>
Cc: Ralf Baechle <ralf@linux-mips.org>,
Markos Chandras <markos.chandras@imgtec.com>,
linux-mips@linux-mips.org, Alex Smith <alex.smith@imgtec.com>,
linux-kernel@vger.kernel.org
Subject: Re: [v3, 3/3] MIPS: VDSO: Add implementations of gettimeofday() and clock_gettime()
Date: Tue, 27 Oct 2015 14:49:14 -0700 [thread overview]
Message-ID: <562FF15A.1050507@imgtec.com> (raw)
Message-ID: <20151027214914.-i23YyngAj8zr2Lt2L95-2xX1jqcd--_dGoYLWkmAoY@z> (raw)
In-Reply-To: <562FF05A.508@gmail.com>
> 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
next prev parent reply other threads:[~2015-10-27 21:49 UTC|newest]
Thread overview: 58+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-09-28 10:03 [PATCH 0/3] MIPS VDSO support Markos Chandras
2015-09-28 10:03 ` Markos Chandras
2015-09-28 10:10 ` [PATCH 1/3] MIPS: Initial implementation of a VDSO Markos Chandras
2015-09-28 10:10 ` Markos Chandras
2015-09-28 10:54 ` Alex Smith
2015-09-28 13:07 ` Matthew Fortune
2015-11-20 18:15 ` Maciej W. Rozycki
2015-10-09 8:05 ` [PATCH v2 " Markos Chandras
2015-10-09 8:05 ` Markos Chandras
2015-10-21 8:54 ` [PATCH v3 " Markos Chandras
2015-10-21 8:54 ` Markos Chandras
2015-09-28 10:11 ` [PATCH 2/3] irqchip: irq-mips-gic: Provide function to map GIC user section Markos Chandras
2015-09-28 10:11 ` Markos Chandras
2015-09-28 10:55 ` Marc Zyngier
2015-09-28 14:16 ` Qais Yousef
2015-09-28 14:16 ` Qais Yousef
2015-09-28 15:03 ` Marc Zyngier
2015-10-05 8:22 ` Markos Chandras
2015-10-05 8:22 ` Markos Chandras
2015-10-12 9:40 ` [PATCH v2 " Markos Chandras
2015-10-12 9:40 ` Markos Chandras
2015-10-12 9:51 ` Marc Zyngier
2015-10-12 10:16 ` Thomas Gleixner
2015-10-15 9:37 ` Qais Yousef
2015-10-15 9:37 ` Qais Yousef
2015-10-15 10:18 ` Thomas Gleixner
2015-09-28 10:12 ` [PATCH 3/3] MIPS: VDSO: Add implementations of gettimeofday() and clock_gettime() Markos Chandras
2015-09-28 10:12 ` Markos Chandras
2015-09-28 13:15 ` kbuild test robot
2015-09-28 13:15 ` kbuild test robot
2015-10-12 10:24 ` [PATCH v2 " Markos Chandras
2015-10-12 10:24 ` Markos Chandras
2015-10-21 8:57 ` [PATCH v3 " Markos Chandras
2015-10-21 8:57 ` Markos Chandras
2015-10-23 1:41 ` [v3, " Leonid Yegoshin
2015-10-23 1:41 ` Leonid Yegoshin
2015-10-27 14:47 ` Ralf Baechle
2015-10-27 20:46 ` Leonid Yegoshin
2015-10-27 20:46 ` Leonid Yegoshin
2015-10-27 21:02 ` David Daney
2015-10-27 21:15 ` Leonid Yegoshin
2015-10-27 21:15 ` Leonid Yegoshin
2015-10-27 21:44 ` David Daney
2015-10-27 21:49 ` Leonid Yegoshin [this message]
2015-10-27 21:49 ` Leonid Yegoshin
2015-10-28 10:20 ` Alex Smith
2015-10-28 18:21 ` Leonid Yegoshin
2015-10-28 18:21 ` Leonid Yegoshin
2015-10-28 18:30 ` Alex Smith
2015-10-28 18:57 ` Leonid Yegoshin
2015-10-28 18:57 ` Leonid Yegoshin
2015-10-28 19:04 ` Alex Smith
2015-10-28 19:28 ` Leonid Yegoshin
2015-10-28 19:28 ` Leonid Yegoshin
2015-10-28 19:55 ` Alex Smith
2015-10-28 20:15 ` Leonid Yegoshin
2015-10-28 20:15 ` Leonid Yegoshin
2016-01-25 22:36 ` [PATCH v3 " Hauke Mehrtens
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