[Bug 2180] New: _TOD_Get_with_nanoseconds() is broken on SMP

[Joel Sherrill]

On 8/20/2014 8:59 AM, Sebastian Huber wrote:
> On 20/08/14 15:53, Joel Sherrill wrote:
>> On 8/20/2014 8:12 AM, Daniel Cederman wrote:
>>>> Hi,
>>>>
>>>> We are currently experiencing this bug reported by Sebastian Huber and I
>>>> could not find any discussion on it on the list. I'm guessing that the
>>>> simple solution of moving the call to Clock_driver_support_at_tick() to
>>>> the critical section of _TOD_Tickle_ticks() is not an acceptable
>>>> solution, given that it would be a call from score to the BSP?
>> I don't have a problem with it. Some documentation may need to be updated to
>> reflect the environment in which the bsp hook is called but I think it
>> is pretty
>> obvious it is called when an accurate timestamp is wanted.
> Its not that easy.  This Clock_driver_support_at_tick() is part of 
> clockdrv_shell.h.  What we need is a proper clock driver API.
>
Grrr.. I should have actually re-read the PR and not tried to remember
the issue.
Sorry. :(

It looks like the entire sequence needs to be locked.  What that exposes is
another matter.

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