Re: [PATCH] intel_idle: mention assumption that wbinvd is not needed

2020-10-12 Thread Rafael J. Wysocki
On Mon, Oct 12, 2020 at 1:14 PM Alexander Monakov wrote: > > On Mon, 12 Oct 2020, Rafael J. Wysocki wrote: > > > > @@ -20,7 +20,11 @@ > > > * All CPUs have same idle states as boot CPU > > > * > > > * Chipset BM_STS (bus master status) bit is a NOP > > > - * for preventing entry into dee

Re: [PATCH] intel_idle: mention assumption that wbinvd is not needed

2020-10-12 Thread Alexander Monakov
On Mon, 12 Oct 2020, Rafael J. Wysocki wrote: > > @@ -20,7 +20,11 @@ > > * All CPUs have same idle states as boot CPU > > * > > * Chipset BM_STS (bus master status) bit is a NOP > > - * for preventing entry into deep C-stats > > + * for preventing entry into deep C-states > > + * > >

Re: [PATCH] intel_idle: mention assumption that wbinvd is not needed

2020-10-12 Thread Rafael J. Wysocki
On Sun, Oct 11, 2020 at 1:13 AM Alexander Monakov wrote: > > Intel SDM does not explicitly say that entering a C-state via MWAIT will > implicitly flush CPU caches as appropriate for that C-state. However, > documentation for individual Intel CPU generations does mention this > behavior. > > Since

[PATCH] intel_idle: mention assumption that wbinvd is not needed

2020-10-10 Thread Alexander Monakov
Intel SDM does not explicitly say that entering a C-state via MWAIT will implicitly flush CPU caches as appropriate for that C-state. However, documentation for individual Intel CPU generations does mention this behavior. Since intel_idle binds to any Intel CPU with MWAIT, mention this assumption