Re: [PATCH] x86/alternatives: remove false sharing in poke_int3_handler()

[Ingo Molnar]

* Eric Dumazet <edumazet@xxxxxxxxxx> wrote:

> > What's the adversarial workload here? Spamming bpf_stats_enabled on all
> > CPUs in parallel? Or mixing it with some other text_poke_bp_batch()
> > user if bpf_stats_enabled serializes access?
            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

> > Does anything undesirable happen in that case?
> 
> The case of multiple threads trying to flip bpf_stats_enabled is
> handled by bpf_stats_enabled_mutex.

So my suggested workload wasn't adversarial enough due to 
bpf_stats_enabled_mutex: how about some other workload that doesn't 
serialize access to text_poke_bp_batch()?

Thanks,

	Ingo