Alexander, On Thu, 27 Jun 2019, Sverdlin, Alexander (Nokia - DE/Ulm) wrote:
> On 24/06/2019 11:40, Thomas Gleixner wrote: > >>> The alternative solution for this is what Vincenzo has in his unified VDSO > >>> patch series: > >>> > >>> > >>> https://lkml.kernel.org/r/[email protected] > >>> > >>> It leaves the data struct unmodified and has a separate array for the raw > >>> clock. That does not have the side effects at all. > >>> > >>> I'm in the process of merging that series and I actually adapted your > >>> scheme to the new unified infrastructure where it has exactly the same > >>> effects as with your original patches against the x86 version. > >> please let me know if I need to rework [2/2] based on some > >> not-yet-published > >> branch of yours. > > I've pushed it out now to > > > > git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git timers/vdso > > > > The generic VDSO library has the support for RAW already with that separate > > array. Testing would be welcomed! > > Thanks for your and Vincenzo's efforts! > I've applied the series onto 5.2.0-rc6 and did a quick test on a bare x86_64 > and > for me it looks good: Did you use the git tree? If not, it would be interesting to have a test against that as well because that's the final version. > Number of clock_gettime() calls in 10 seconds: > > Before After Diff > MONOTONIC 152404300 200825950 +32% > MONOTONIC_RAW 38804788 198765053 +412% > REALTIME 151672619 201371468 +33% The increase for mono and realtime is impressive. Which CPU is that? Thanks, tglx
