On Wed, Mar 10, 2021 at 08:37:56AM -0800, kan.li...@linux.intel.com wrote: > From: Kan Liang <kan.li...@linux.intel.com> > > Alder Lake Hybrid system has two different types of core, Golden Cove > core and Gracemont core. The Golden Cove core is registered to > "cpu_core" PMU. The Gracemont core is registered to "cpu_atom" PMU. > > The difference between the two PMUs include: > - Number of GP and fixed counters > - Events > - The "cpu_core" PMU supports Topdown metrics. > The "cpu_atom" PMU supports PEBS-via-PT. > > The "cpu_core" PMU is similar to the Sapphire Rapids PMU, but without > PMEM. > The "cpu_atom" PMU is similar to Tremont, but with different > event_constraints, extra_regs and number of counters. >
> + /* Initialize big core specific PerfMon capabilities.*/ > + pmu = &x86_pmu.hybrid_pmu[X86_HYBRID_PMU_CORE_IDX]; > + pmu->name = "cpu_core"; > + /* Initialize Atom core specific PerfMon capabilities.*/ > + pmu = &x86_pmu.hybrid_pmu[X86_HYBRID_PMU_ATOM_IDX]; > + pmu->name = "cpu_atom"; So do these things use the same event lists as SPR and TNT? Is there any way to discover that, because AFAICT /proc/cpuinfo will say every CPU is 'Alderlake', and the above also doesn't give any clue. FWIW, ARM big.LITTLE does discriminate in its /proc/cpuinfo, but I'm not entirely sure it's really useful. Mark said perf userspace uses somethink akin to our CPUID, except exposed through sysfs, to find the event lists. My desktop has: cpu/caps/pmu_name and that gives "skylake", do we want the above to have cpu_core/caps/pmu_name give "sapphire_rapids" etc.. ?
