Messages in this thread | | | Subject | Re: [PATCH V2 1/25] x86/cpufeatures: Enumerate Intel Hybrid Technology feature bit | From | "Liang, Kan" <> | Date | Wed, 10 Mar 2021 17:32:21 -0500 |
| |
On 3/10/2021 5:25 PM, Ricardo Neri wrote: > On Wed, Mar 10, 2021 at 09:01:47PM +0100, Borislav Petkov wrote: >> On Wed, Mar 10, 2021 at 11:46:44AM -0800, Ricardo Neri wrote: >>> But this series provides the use case, right? Kan's patches handle PMU counters >>> that may differ cross types of CPUs. In patch 2, get_hybrid_params() >>> needs to check first if X86_FEATURE_HYBRID_CPU is enabled before >>> querying the hybrid parameters. Otherwise, we would need to rely on the >>> maximum level of CPUID, which may not be reliable. >> >> On Wed, Mar 10, 2021 at 11:33:54AM -0800, Srinivas Pandruvada wrote: >>> We are working on changes to P-State driver for hybrid CPUs using this >>> define. They are still work in progress. >>> But this patch can be submitted later with our set of changes. >> >> Answering to both with a single mail: >> >> I don't have a problem with X86_FEATURE_HYBRID_CPU - I simply don't want >> to show "hybrid_cpu" in /proc/cpuinfo unless there's a valid use case >> for userspace to know that it is running on a hybrid CPU. > > Ah, I get your point now. You would like to see > > #define X86_FEATURE_HYBRID_CPU (18*32+15) /* "" This part has CPUs of more than one type */ > > Right? Now your first comment makes sense. > > Srinivas, Kan, I don't think we need to expose "hybrid_cpu" in > /proc/cpuinfo, do we? >
Right, Perf doesn't use the "hybrid_cpu" in /proc/cpuinfo.
Thanks, Kan
| |