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[Xen-devel] evtchn_do_upcall() barrier between upcall_pending and pendin

To: xen-devel@xxxxxxxxxxxxxxxxxxx
Subject: [Xen-devel] evtchn_do_upcall() barrier between upcall_pending and pending_sel
From: Samuel Thibault <samuel.thibault@xxxxxxxxxxxxx>
Date: Thu, 8 May 2008 11:18:29 +0100
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Hello,

In evtchn_do_upcall() there is a barrier between setting upcall_pending
and pending_sel, which makes sense to avoid losing events, however I
don't understand why it is a rmb(). memory-barriers.txt says that rmb()
only provides ordering of reads, not stores.  Shouldn't that be a wmb()
instead then?

Samuel

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