From mboxrd@z Thu Jan 1 00:00:00 1970 From: Benjamin Herrenschmidt Subject: Re: [PATCH 4/4] KVM: PPC: align vcpu_kick with x86 Date: Sat, 24 Dec 2011 08:50:11 +1100 Message-ID: <1324677011.6632.15.camel@pasglop> References: <1323444412-18482-1-git-send-email-agraf@suse.de> <1323444412-18482-5-git-send-email-agraf@suse.de> <4EE25137.4090402@freescale.com> <7C199265-906A-4173-97F1-BF51856ACFD2@suse.de> <4EE25E56.3070902@freescale.com> <87C18322-1455-46B5-ACA6-F8786D850C1B@suse.de> <4EE63AB0.1030202@freescale.com> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Cc: Scott Wood , kvm-ppc@vger.kernel.org, =?ISO-8859-1?Q?J=F6rg?= Sommer , KVM list To: Alexander Graf Return-path: In-Reply-To: Sender: kvm-ppc-owner@vger.kernel.org List-Id: kvm.vger.kernel.org On Fri, 2011-12-23 at 13:56 +0100, Alexander Graf wrote: > > Hmm, unless smp_send_reschedule must be called with preemption disabled > > (doesn't seem like an obvious requirement, even if callers commonly have > > a reason to do so, and the only documentation of it I see is on the ia64 > > implementation), that seems like a bug in the MPIC IPI implementation. > > > > It wouldn't be an issue (and would make the MPIC driver slightly faster, > > too) if the MPIC driver were to use the magic CPU region instead of > > manually indexing the non-magic array of per-CPU regions. Maybe it > > doesn't work on all hardware the driver supports? Right, the magic per-cpu region doesn't work on all HW. > I'd say that's a question I'll redirect to Ben :). > > > Not that it matters much here -- we want this patch anyway, because we > > want to check that it's not the current CPU. > > Yeah. Well - eventually we want the exact same vcpu_kick function across architectures. > But this is a good step in the right direction. Cheers, Ben.