From mboxrd@z Thu Jan 1 00:00:00 1970 From: Boris Ostrovsky Subject: Re: [PATCH tip/core/rcu 02/20] x86: Use common outgoing-CPU-notification code Date: Wed, 04 Mar 2015 11:10:15 -0500 Message-ID: <54F72E67.1000206__19280.8451400653$1425485698$gmane$org@oracle.com> References: <20150303174144.GA13139@linux.vnet.ibm.com> <1425404595-17816-1-git-send-email-paulmck@linux.vnet.ibm.com> <1425404595-17816-2-git-send-email-paulmck@linux.vnet.ibm.com> <54F608C4.40405@oracle.com> <20150303194223.GR15405@linux.vnet.ibm.com> <54F615D3.2040802@oracle.com> <20150303212647.GZ15405@linux.vnet.ibm.com> <54F6307A.8040003@oracle.com> <20150303223151.GC15405@linux.vnet.ibm.com> <20150304144336.GA8225@linux.vnet.ibm.com> <54F71CCF.9050509@oracle.com> <54F72891.5070805@citrix.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii"; Format="flowed" Content-Transfer-Encoding: 7bit Return-path: Received: from mail6.bemta5.messagelabs.com ([195.245.231.135]) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YTBuf-0000Hp-9f for xen-devel@lists.xenproject.org; Wed, 04 Mar 2015 16:12:45 +0000 In-Reply-To: <54F72891.5070805@citrix.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: David Vrabel , paulmck@linux.vnet.ibm.com Cc: tglx@linutronix.de, laijs@cn.fujitsu.com, bobby.prani@gmail.com, peterz@infradead.org, fweisbec@gmail.com, dvhart@linux.intel.com, x86@kernel.org, oleg@redhat.com, linux-kernel@vger.kernel.org, rostedt@goodmis.org, josh@joshtriplett.org, dhowells@redhat.com, edumazet@google.com, mathieu.desnoyers@efficios.com, dipankar@in.ibm.com, xen-devel@lists.xenproject.org, akpm@linux-foundation.org, mingo@kernel.org List-Id: xen-devel@lists.xenproject.org On 03/04/2015 10:45 AM, David Vrabel wrote: > On 04/03/15 14:55, Boris Ostrovsky wrote: >> In the meantime, it turned out that HVM guests are broken by this patch >> (with our without changes that we've been discussing), because HVM CPUs >> die with >> >> static void xen_hvm_cpu_die(unsigned int cpu) >> { >> xen_cpu_die(cpu); >> native_cpu_die(cpu); >> } >> >> Which means that cpu_wait_death() is called twice, and second call moves >> the CPU to CPU_BROKEN. >> >> The simple solution is to stop calling native_cpu_die() above but I'd >> like to use common code in native_cpu_die(). I'll see if I can carve it >> out without too much damage to x86. > If not really been following this thread but... > > Would it be preferable to refactor xen_cpu_die() instead to factor out > its the cpu_wait_death() call? That's essentially what I was going to do. Except that native_cpu_die() returns void so I'll need some common non-void code that lives in x86. And then we can drop xen_hvm_cpu_die() and use xen_cpu_die() for all guests. -boris