Re: [PATCH v4 12/13] mips: csrc-r4k: Mark R4K timer as unstable if CPU freq changes

From: Thomas Bogendoerfer
Date: Fri May 22 2020 - 03:31:28 EST


On Thu, May 21, 2020 at 05:07:23PM +0300, Serge Semin wrote:
> Commit 07d69579e7fe ("MIPS: Don't register r4k sched clock when CPUFREQ
> enabled") disabled the r4k-clock usage for scheduler ticks counting due
> to the scheduler being non-tolerant for unstable clocks sources. For the
> same reason the clock should be used in the system clocksource framework
> with care. As soon as CPU frequency changes the clocksource framework
> should be notified about this by marking the R4K timer being unstable
> (which it really is, since the ticks rate has been changed synchronously
> with the CPU frequency).
>
> Signed-off-by: Serge Semin <Sergey.Semin@xxxxxxxxxxxxxxxxxxxx>
> Cc: Alexey Malahov <Alexey.Malahov@xxxxxxxxxxxxxxxxxxxx>
> Cc: Thomas Bogendoerfer <tsbogend@xxxxxxxxxxxxxxxx>
> Cc: Paul Burton <paulburton@xxxxxxxxxx>
> Cc: Ralf Baechle <ralf@xxxxxxxxxxxxxx>
> Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
> Cc: Arnd Bergmann <arnd@xxxxxxxx>
> Cc: Rob Herring <robh+dt@xxxxxxxxxx>
> Cc: devicetree@xxxxxxxxxxxxxxx
> ---
> arch/mips/Kconfig | 1 +
> arch/mips/kernel/csrc-r4k.c | 40 +++++++++++++++++++++++++++++++++++++
> 2 files changed, 41 insertions(+)

applied to mips-next.

Thomas.

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