> On 21 Jul 2026, at 18:03, Andi Kleen <[email protected]> wrote: > > On Tue, Jul 21, 2026 at 04:29:15PM +0200, [email protected] wrote: >> From: Kyrylo Tkachov <[email protected]> >> >> The autoprofile bootstrap support probes for Arm SPE from gcc/configure, >> gcc-auto-profile, and the profile-optimization testsuite support. Each >> bare "perf list" scans every event class even though arm_spe is a PMU. >> This can make the probe unnecessarily slow on systems with many events. >> >> Use "perf list pmu" at all three call sites. The PMU event class filter >> has long been supported by perf and still reports arm_spe. Stubbed BRBE, >> SPE, and fallback paths select the same profiler as before. >> >> This patch actually saves a few minutes of end-to-end bootstrap time on my >> SPE >> AArch64 many-core system. > > Or just -d /sys/devices/arm_spe ? (or what the right PMU name is) > But yes it's a clear improvement.
I think it has to be /sys/bus/event_source/devices/arm_spe_0 after https://github.com/torvalds/linux/commit/4052ce07d5d7 Tbh "perf list pmu” looks easier to me unless there are concerns with perf availability or something? > > BTW do you actually see a faster compiler out of autoprofiledbootstrap? > I currently don't on x86. I haven’t done thorough evaluation of that myself (isolated compute time on my big build machines is hard to get exclusively at the moment), I was just picking some low hanging fruit on improving bootstrap times on aarch64. Thanks for looking at this, Kyrill > > -Andi >
