Messages in this thread | | | From | Andy Lutomirski <> | Date | Thu, 16 Jan 2020 12:19:50 -0800 | Subject | Re: [RFC PATCH v4 08/11] lib: vdso: allow fixed clock mode |
| |
On Thu, Jan 16, 2020 at 12:14 PM Thomas Gleixner <tglx@linutronix.de> wrote: > > Christophe Leroy <christophe.leroy@c-s.fr> writes: > > Can you please adjust the prefix for future patches to lib/vdso: and > start the sentence after the colon with an uppercase letter? > > > On arches like POWERPC, the clock is always the timebase, it > > Please spell out architectures. Changelogs are not space constraint. > > > cannot be changed on the fly and it is always VDSO capable. > > Also this sentence does not make sense as it might suggests that > architectures with a fixed compile time known clocksource have something > named timebase. Something like this is more clear: > > Some architectures have a fixed clocksource which is known at compile > time and cannot be replaced or disabled at runtime, e.g. timebase on > PowerPC. For such cases the clock mode check in the VDSO code is > pointless. >
I wonder if we should use this on x86 bare-metal if we have sufficiently invariant TSC. (Via static_cpu_has(), not compiled in.) Maybe there is no such x86 machine.
I really really want Intel or AMD to introduce machines where the TSC pinky-swears to count in actual nanoseconds.
--Andy
| |