Re: [PATCH 0/4] perf: Fix the ctx->pmu for a hybrid system

[Peter Zijlstra]

On Wed, Jun 16, 2021 at 11:55:30AM -0700, kan.liang@xxxxxxxxxxxxxxx wrote:

> To fix the issue, the generic perf codes have to understand the
> supported CPU mask of a specific hybrid PMU. So it can update the
> ctx->pmu accordingly, when a task is scheduled on a CPU which has
> a different type of PMU from the previous CPU. The supported_cpus
> has to be moved to the struct pmu.

Urghh.. I so hate this :-/

I *did* point you to:

  https://lore.kernel.org/lkml/20181010104559.GO5728@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx/

when you started this whole hybrid crud, and I think that's still the
correct thing to do.

Still, let me consider if there's a workable short-term cludge I hate
less.