Re: [PATCH] ring-buffer: speed up buffer resets by avoiding synchronize_rcu for each CPU

[Steven Rostedt]

On Thu, 25 Jun 2020 15:34:03 +1000
Nicholas Piggin <npiggin@xxxxxxxxx> wrote:

> Batch these up so we disable all the per-cpu buffers first, then
> synchronize_rcu() once, then reset each of the buffers. This brings
> the time down to about 0.5s.

After applying this patch, running tools/testing/selftests/ftracetest
went from 5 minutes and 35 seconds to 5 minutes 5 seconds to complete
on my 4 core (8 with hyperthreading) machine! That's almost a 10% drop!

Thanks, I'm definitely applying this for the next merge window.

-- Steve