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Date:   Thu, 6 Jul 2023 00:41:04 +0200
From:   Peter Zijlstra <peterz@infradead.org>
To:     Frederic Weisbecker <frederic@kernel.org>
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Subject: Re: [RFC PATCH 11/14] context-tracking: Introduce work deferral
 infrastructure
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On Thu, Jul 06, 2023 at 12:23:57AM +0200, Frederic Weisbecker wrote:
> If this is just about a dozen, can we stuff them in the state like in the
> following? We can potentially add more of them especially on 64 bits we could
> afford 30 different works, this is just shrinking the RCU extended quiescent
> state counter space. Worst case that can happen is that RCU misses 65535
> idle/user <-> kernel transitions and delays a grace period...

We can make all this a 64bit only feature and use atomic_long_t :-)