Re: Endless soft-lockups for compiling workload since next-20200519

From: Peter Zijlstra
Date: Thu May 21 2020 - 06:11:03 EST


On Thu, May 21, 2020 at 02:40:36AM +0200, Frederic Weisbecker wrote:

> atomic_fetch_or(...., nohz_flags(0))
> softirq() { #VMEXIT or anything that could stop a CPU for a while
> run_rebalance_domain() {
> nohz_idle_balance() {
> atomic_andnot(NOHZ_KICK_MASK, nohz_flag(0))

I'm an idiot and didn't have enough wake-up-juice; I missed that andnot
clearing the flag again.

Yes, fun fun fun..