Re: [PATCH] clocksource/drivers/pistachio: Fix wrong calculated clocksource read value

From: Daniel Lezcano
Date: Tue Dec 15 2015 - 15:59:33 EST


On 11/25/2015 04:42 PM, Jisheng Zhang wrote:
Let's assume the counter value is 0xf000000, the pistachio clocksource
read cycles function would return 0xffffffff0fffffff, but it should
return 0xfffffff.

We fix this issue by calculating bitwise-not counter, then cast to
cycle_t.

Signed-off-by: Jisheng Zhang <jszhang@xxxxxxxxxxx>

Hi Jisheng,

I tried to reproduce this behavior on x86_64 but without success.

On which architecture did you produce this result ? Do you have a simple test program to check with ?

Thanks

-- Daniel


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