From mboxrd@z Thu Jan 1 00:00:00 1970 From: Konrad Rzeszutek Wilk Subject: Re: Linux v3.12 + pv ticketlocks Date: Wed, 11 Sep 2013 14:41:29 -0400 Message-ID: <20130911184129.GA30042@phenom.dumpdata.com> References: <20130906201113.GA25693@phenom.dumpdata.com> <1464013377.20130911202501@eikelenboom.it> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: <1464013377.20130911202501@eikelenboom.it> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: Sander Eikelenboom Cc: xen-devel@lists.xensource.com List-Id: xen-devel@lists.xenproject.org On Wed, Sep 11, 2013 at 08:25:01PM +0200, Sander Eikelenboom wrote: > Hi Konrad, > > Just to confirm: > > - PV ticketlocks is on by default and doesn't neet a config option, to disable it at boot time it's possible to use "xen_nopvspin" as a kernel commandline parameter Yes. > - CONFIG_PARAVIRT_SPINLOCKS should be off, since that would enable the old bytelock pv-spinlock implementation which could now probably be removed ? You still need CONFIG_PARAVIRT_SPINLOCKS=y to take advantage of it. The bytelock pvspinlock is gone. If you compile without CONFIG_PARAVIRT_SPINLOCKS then you will only use ticketlocks for all types of guests and baremtal. No 'PV' variant. The CONFIG_PARAVIRT_SPINLOCKS=y enables the PV ticketlock for all guests. > > Have a nice vacation ! > > -- > Sander >