Displaying 7 results from an estimated 7 matches for "clock_thread_cputime".
2018 Sep 14
2
[patch 11/11] x66/vdso: Add CLOCK_TAI support
...5:50 AM, Thomas Gleixner <tglx at linutronix.de> wrote:
>
> With the storage array in place it's now trivial to support CLOCK_TAI in
> the vdso. Instead of extending the array to accomodate CLOCK_TAI, make use
> of the fact that:
>
> - CLOCK ids are set in stone
> - CLOCK_THREAD_CPUTIME is never going to be supported in the VDSO so
> the array slot 3 is unused
> - CLOCK_TAI is id 11 which results in 3 when masked with 0x3
>
> Add the mask to the basetime array lookup and set up the CLOCK_TAI base
> time in update_vsyscall().
That?s... horrible. In an amazing way...
2018 Sep 14
2
[patch 11/11] x66/vdso: Add CLOCK_TAI support
...5:50 AM, Thomas Gleixner <tglx at linutronix.de> wrote:
>
> With the storage array in place it's now trivial to support CLOCK_TAI in
> the vdso. Instead of extending the array to accomodate CLOCK_TAI, make use
> of the fact that:
>
> - CLOCK ids are set in stone
> - CLOCK_THREAD_CPUTIME is never going to be supported in the VDSO so
> the array slot 3 is unused
> - CLOCK_TAI is id 11 which results in 3 when masked with 0x3
>
> Add the mask to the basetime array lookup and set up the CLOCK_TAI base
> time in update_vsyscall().
That?s... horrible. In an amazing way...
2018 Sep 14
0
[patch 11/11] x66/vdso: Add CLOCK_TAI support
With the storage array in place it's now trivial to support CLOCK_TAI in
the vdso. Instead of extending the array to accomodate CLOCK_TAI, make use
of the fact that:
- CLOCK ids are set in stone
- CLOCK_THREAD_CPUTIME is never going to be supported in the VDSO so
the array slot 3 is unused
- CLOCK_TAI is id 11 which results in 3 when masked with 0x3
Add the mask to the basetime array lookup and set up the CLOCK_TAI base
time in update_vsyscall().
The performance impact of the mask operation is within the n...
2018 Sep 14
0
[patch 11/11] x66/vdso: Add CLOCK_TAI support
...t linutronix.de> wrote:
> >
> > With the storage array in place it's now trivial to support CLOCK_TAI in
> > the vdso. Instead of extending the array to accomodate CLOCK_TAI, make use
> > of the fact that:
> >
> > - CLOCK ids are set in stone
> > - CLOCK_THREAD_CPUTIME is never going to be supported in the VDSO so
> > the array slot 3 is unused
> > - CLOCK_TAI is id 11 which results in 3 when masked with 0x3
> >
> > Add the mask to the basetime array lookup and set up the CLOCK_TAI base
> > time in update_vsyscall().
>
> Th...
2018 Sep 14
1
[patch 11/11] x66/vdso: Add CLOCK_TAI support
...rote:
>>>
>>> With the storage array in place it's now trivial to support CLOCK_TAI in
>>> the vdso. Instead of extending the array to accomodate CLOCK_TAI, make use
>>> of the fact that:
>>>
>>> - CLOCK ids are set in stone
>>> - CLOCK_THREAD_CPUTIME is never going to be supported in the VDSO so
>>> the array slot 3 is unused
>>> - CLOCK_TAI is id 11 which results in 3 when masked with 0x3
>>>
>>> Add the mask to the basetime array lookup and set up the CLOCK_TAI base
>>> time in update_vsyscall()....
2018 Sep 14
24
[patch 00/11] x86/vdso: Cleanups, simmplifications and CLOCK_TAI support
Matt attempted to add CLOCK_TAI support to the VDSO clock_gettime()
implementation, which extended the clockid switch case and added yet
another slightly different copy of the same code.
Especially the extended switch case is problematic as the compiler tends to
generate a jump table which then requires to use retpolines. If jump tables
are disabled it adds yet another conditional to the existing
2018 Sep 14
24
[patch 00/11] x86/vdso: Cleanups, simmplifications and CLOCK_TAI support
Matt attempted to add CLOCK_TAI support to the VDSO clock_gettime()
implementation, which extended the clockid switch case and added yet
another slightly different copy of the same code.
Especially the extended switch case is problematic as the compiler tends to
generate a jump table which then requires to use retpolines. If jump tables
are disabled it adds yet another conditional to the existing