Re: [PATCH v2 tip/core/rcu 01/22] smpboot: Add common code for notification from dying CPU

On Tue, Mar 17, 2015 at 09:18:07AM +0100, Peter Zijlstra wrote:

On Mon, Mar 16, 2015 at 11:37:45AM -0700, Paul E. McKenney wrote:

quoted

From: "Paul E. McKenney" <redacted>

RCU ignores offlined CPUs, so they cannot safely run RCU read-side code.
(They -can- use SRCU, but not RCU.)  This means that any use of RCU
during or after the call to arch_cpu_idle_dead().  Unfortunately,
commit 2ed53c0d6cc99 added a complete() call, which will contain RCU
read-side critical sections if there is a task waiting to be awakened.

Got a little more detail there?

Quite possibly.  But exactly what sort of detail are you looking for?

							Thanx, Paul