perf/x86/intel: Apply mid ACK for small core
A warning as below may be occasionally triggered in an ADL machine when these conditions occur: - Two perf record commands run one by one. Both record a PEBS event. - Both runs on small cores. - They have different adaptive PEBS configuration (PEBS_DATA_CFG). [ ] WARNING: CPU: 4 PID: 9874 at arch/x86/events/intel/ds.c:1743 setup_pebs_adaptive_sample_data+0x55e/0x5b0 [ ] RIP: 0010:setup_pebs_adaptive_sample_data+0x55e/0x5b0 [ ] Call Trace: [ ] <NMI> [ ] intel_pmu_drain_pebs_icl+0x48b/0x810 [ ] perf_event_nmi_handler+0x41/0x80 [ ] </NMI> [ ] __perf_event_task_sched_in+0x2c2/0x3a0 Different from the big core, the small core requires the ACK right before re-enabling counters in the NMI handler, otherwise a stale PEBS record may be dumped into the later NMI handler, which trigger the warning. Add a new mid_ack flag to track the case. Add all PMI handler bits in the struct x86_hybrid_pmu to track the bits for different types of PMUs. Apply mid ACK for the small cores on an Alder Lake machine. The existing hybrid() macro has a compile error when taking address of a bit-field variable. Add a new macro hybrid_bit() to get the bit-field value of a given PMU. Fixes: f83d2f91 ("perf/x86/intel: Add Alder Lake Hybrid support") Reported-by: Ammy Yi <ammy.yi@intel.com> Signed-off-by: Kan Liang <kan.liang@linux.intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Andi Kleen <ak@linux.intel.com> Tested-by: Ammy Yi <ammy.yi@intel.com> Link: https://lkml.kernel.org/r/1627997128-57891-1-git-send-email-kan.liang@linux.intel.com
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