From mboxrd@z Thu Jan  1 00:00:00 1970
From: peterz@infradead.org (Peter Zijlstra)
Date: Wed, 11 Nov 2015 23:21:35 +0100
Subject: [PATCH 2/2] arm64: bpf: add BPF XADD instruction
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To: linux-arm-kernel@lists.infradead.org
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On Wed, Nov 11, 2015 at 11:55:59AM -0800, Alexei Starovoitov wrote:
> Therefore things like memory barriers, full set of atomics are not applicable
> in bpf world.

There are still plenty of wait-free constructs one can make using them.

Say a barrier/rendezvous construct for knowing when an event has
happened on all CPUs.

But if you really do not want any of that, I suppose that is a valid
choice.


Is even privileged (e)BPF not allowed things like this? I was thinking
the strict no loops stuff was for unpriv (e)BPF only.