Re: [PATCH 1/3] lib/vdso: Delay mask application in do_hres()

2019-06-26 Thread Vincenzo Frascino
Hi Thomas, On 26/06/2019 07:38, Thomas Gleixner wrote: > On Tue, 25 Jun 2019, Thomas Gleixner wrote: >> On Tue, 25 Jun 2019, Vincenzo Frascino wrote: >>> do_hres() in the vDSO generic library masks the hw counter value >>> immediately after reading it. >>> >>> Postpone the mask application after

Re: [PATCH 1/3] lib/vdso: Delay mask application in do_hres()

2019-06-26 Thread Thomas Gleixner
On Tue, 25 Jun 2019, Thomas Gleixner wrote: > On Tue, 25 Jun 2019, Vincenzo Frascino wrote: > > do_hres() in the vDSO generic library masks the hw counter value > > immediately after reading it. > > > > Postpone the mask application after checking if the syscall fallback is > > enabled, in order

Re: [PATCH 1/3] lib/vdso: Delay mask application in do_hres()

2019-06-25 Thread Thomas Gleixner
On Tue, 25 Jun 2019, Andy Lutomirski wrote: > On Tue, Jun 25, 2019 at 11:27 AM Thomas Gleixner wrote: > > > > On Tue, 25 Jun 2019, Thomas Gleixner wrote: > > > > > On Tue, 25 Jun 2019, Vincenzo Frascino wrote: > > > > > > CC+ Andy > > > > > > > do_hres() in the vDSO generic library masks the hw

Re: [PATCH 1/3] lib/vdso: Delay mask application in do_hres()

2019-06-25 Thread Andy Lutomirski
On Tue, Jun 25, 2019 at 11:27 AM Thomas Gleixner wrote: > > On Tue, 25 Jun 2019, Thomas Gleixner wrote: > > > On Tue, 25 Jun 2019, Vincenzo Frascino wrote: > > > > CC+ Andy > > > > > do_hres() in the vDSO generic library masks the hw counter value > > > immediately after reading it. > > > > > >

Re: [PATCH 1/3] lib/vdso: Delay mask application in do_hres()

2019-06-25 Thread Thomas Gleixner
On Tue, 25 Jun 2019, Thomas Gleixner wrote: > On Tue, 25 Jun 2019, Vincenzo Frascino wrote: > > CC+ Andy > > > do_hres() in the vDSO generic library masks the hw counter value > > immediately after reading it. > > > > Postpone the mask application after checking if the syscall fallback is > >

Re: [PATCH 1/3] lib/vdso: Delay mask application in do_hres()

2019-06-25 Thread Thomas Gleixner
On Tue, 25 Jun 2019, Vincenzo Frascino wrote: CC+ Andy > do_hres() in the vDSO generic library masks the hw counter value > immediately after reading it. > > Postpone the mask application after checking if the syscall fallback is > enabled, in order to be able to detect a possible fallback for

[PATCH 1/3] lib/vdso: Delay mask application in do_hres()

2019-06-25 Thread Vincenzo Frascino
do_hres() in the vDSO generic library masks the hw counter value immediately after reading it. Postpone the mask application after checking if the syscall fallback is enabled, in order to be able to detect a possible fallback for the architectures that have masks smaller than ULLONG_MAX.