Re: rcu_sched stall while waiting in csd_lock_wait()

From: Pratyush Anand
Date: Wed Aug 02 2017 - 23:56:16 EST

Hi Peter,

On Wednesday 02 August 2017 01:44 PM, Peter Zijlstra wrote:
On Wed, Aug 02, 2017 at 09:01:19AM +0530, Pratyush Anand wrote:

I am observing following rcu_sched stall while executing `perf record -a --
sleep 1` with one of the arm64 platform. It looks like that stalled cpu was
waiting in csd_lock_wait() from where it never came out,and so the stall.
Any help/pointer for further debugging would be very helpful. Problem also
reproduced with 4.13.0-rc3.

I'm sitting on this patch:

please give that a spin.

Thanks for the pointer.
Tried, but it did not help.