profilingperf

what's the equivalent of Last Branch Record (LBR) on ARM and POWERPC?

I'm collecting some profiling information on intel using perf record about taken branches and I'm using -b to make use of LBR. Is there any similar support on ARM and PowerPC? And yes I've seen this: Is Intel's Last Branch Record feature unique to Intel processors?

Solution

  • For ARM CPUs this option has been available since ARMv9.2-A - it's called Branch Record Buffer Extension (BRBE). More information about the topic: https://lwn.net/Articles/951316/ .

    Regarding PowerPC. Just got an update from PowerPC maintainers in the Linux kernel. For PowerPC, such a feature is called Branch History Rolling Buffer (BHRB). It's available since Power8 (~2013).