[Devel] [PATCH rh7 1/2] vdso: virtualized monotonic gettime through vdso

[Dmitry Safonov]

On 05/24/2017 07:45 PM, Andrey Ryabinin wrote:
> 
> 
> On 05/24/2017 07:38 PM, Dmitry Safonov wrote:
>> On 05/24/2017 07:34 PM, Andrey Ryabinin wrote:
>>>
>>>
>>> On 05/24/2017 07:29 PM, Dmitry Safonov wrote:
>>>> On 05/24/2017 06:21 PM, Andrey Ryabinin wrote:
>>>>> We already have infrastructure for virtualized vdso, however we use
>>>>> it only to change LINUX_VERSION_NAME in container. Simply store container's
>>>>> start time - ve->start_timespec in vdso variable - VDSO64_ve_start_timespec,
>>>>> and use it in __vdso_clock_gettime() to calculate container's monotonic time.
>>>>>
>>>>> Make uts_arch_setup_additional_pages()/uts_prep_vdso_pages_locked() to always
>>>>> setup new vdso, since previous policy to setup vdso only if uts_ns->name.release
>>>>> wouldn't work for virtualized __vdso_clock_gettime()
>>>>>
>>>>> https://jira.sw.ru/browse/PSBM-66451
>>>>> Signed-off-by: Andrey Ryabinin <aryabinin at virtuozzo.com>
>>>>
>>>> Well, that's all looks good, but I've two questions:
>>>>
>>>> 1. Where VDSO64_ve_start_timespec is set? I do not see that part.
>>>>
>>>
>>> in uts_arch_setup_additional_pages() and uts_prep_vdso_pages_locked()
>>
>> Uhm, yes, but that means that ve_ts_write() is broken for
>> running CT.
>>
> 
> Do we care? Changing monotonic time on the fly doesn't sound like a brilliant idea.

Ok, if that's not used by vz tools, then:
Reviewed-by: Dmitry Safonov <dsafonov at virtuozzo.com>

-- 
              Dmitry