From mboxrd@z Thu Jan 1 00:00:00 1970 From: Raghavendra K T Subject: [PATCH RFC V7 6/12] xen/pvticketlocks: add xen_nopvspin parameter to disable xen pv ticketlocks Date: Fri, 20 Apr 2012 01:44:39 +0530 Message-ID: <20120419201435.5411.86444.sendpatchset@codeblue> References: <20120419201209.5411.43877.sendpatchset@codeblue> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20120419201209.5411.43877.sendpatchset@codeblue> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: virtualization-bounces@lists.linux-foundation.org Errors-To: virtualization-bounces@lists.linux-foundation.org To: "H. Peter Anvin" , Ingo Molnar Cc: Andrew Jones , Raghavendra K T , KVM , Konrad Rzeszutek Wilk , Peter Zijlstra , LKML , Stephan Diestelhorst , the arch/x86 maintainers , Srivatsa Vaddagiri , Virtualization , Andi Kleen , Avi Kivity , Jeremy Fitzhardinge , Attilio Rao , Linus Torvalds , Xen Devel , Stefano Stabellini List-Id: xen-devel@lists.xenproject.org From: Jeremy Fitzhardinge Signed-off-by: Jeremy Fitzhardinge Reviewed-by: Konrad Rzeszutek Wilk Signed-off-by: Raghavendra K T --- arch/x86/xen/spinlock.c | 14 ++++++++++++++ 1 files changed, 14 insertions(+), 0 deletions(-) diff --git a/arch/x86/xen/spinlock.c b/arch/x86/xen/spinlock.c index 982e64b..c9bf890 100644 --- a/arch/x86/xen/spinlock.c +++ b/arch/x86/xen/spinlock.c @@ -223,12 +223,26 @@ void xen_uninit_lock_cpu(int cpu) unbind_from_irqhandler(per_cpu(lock_kicker_irq, cpu), NULL); } +static bool xen_pvspin __initdata = true; + void __init xen_init_spinlocks(void) { + if (!xen_pvspin) { + printk(KERN_DEBUG "xen: PV spinlocks disabled\n"); + return; + } + pv_lock_ops.lock_spinning = xen_lock_spinning; pv_lock_ops.unlock_kick = xen_unlock_kick; } +static __init int xen_parse_nopvspin(char *arg) +{ + xen_pvspin = false; + return 0; +} +early_param("xen_nopvspin", xen_parse_nopvspin); + #ifdef CONFIG_XEN_DEBUG_FS static struct dentry *d_spin_debug;