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Re: [Xen-devel] [PATCH v2] x86/time: Adjust init-time handling of pit0_ticks

On 08/02/17 13:10, Jan Beulich wrote:
>>>> On 07.02.17 at 19:51, <andrew.cooper3@xxxxxxxxxx> wrote:
>> There is no need for the volatile cast in the timer interrupt; the compiler
>> may not elide the update.  This reduces the generated assembly from a read,
>> local modify, write to a single add instruction.
>> Drop the memory barriers from timer_irq_works(), as they are not needed.
>> pit0_ticks is only modified by timer_interrupt() running on the same CPU, so
>> that is required is a volatile reference to prevent the compiler from eliding
>> the second read.
>> Signed-off-by: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
> Reviewed-by: Jan Beulich <jbeulich@xxxxxxxx>
> Is there an "all" missing at the beginning of the last line of the
> description?

Yes.  Fixed.



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