Performance Monitoring Unit (PMU) Driver Subsystem
A top-level kernel subsystem directory that collects performance monitoring unit drivers from many different SoC and CPU vendors. These drivers expose hardware counters (cache misses, cycles, memory bandwidth, interconnect traffic, etc.) so tools like perf(1) can profile applications and the kernel itself.
This is not actually a driver directory; it is an umbrella subsystem that hosts dozens of unrelated PMU drivers for ARM, RISC-V, x86 uncore, and various SoC interconnects. Any keep-or-remove decision has to be made driver-by-driver inside the directory, not at this level.
repository signals
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138authors, 5y
monthly commits · 2021-04-21 → 2026-04-21 · 566 total · active in 57/61 months
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codex reasoning notes (technical)
Not a driver directory: top-level subsystem directory aggregating many unrelated PMU/performance-monitor drivers, not one hardware driver/chipset implementation.