From mboxrd@z Thu Jan 1 00:00:00 1970 From: Raghavendra K T Subject: [PATCH RFC V6 6/11] xen/pvticketlocks: add xen_nopvspin parameter to disable xen pv ticketlocks Date: Wed, 21 Mar 2012 15:51:49 +0530 Message-ID: <20120321102149.473.80864.sendpatchset@codeblue.in.ibm.com> References: <20120321102041.473.61069.sendpatchset@codeblue.in.ibm.com> Return-path: In-Reply-To: <20120321102041.473.61069.sendpatchset@codeblue.in.ibm.com> Sender: linux-kernel-owner@vger.kernel.org To: "H. Peter Anvin" , Ingo Molnar Cc: Linus Torvalds , Peter Zijlstra , the arch/x86 maintainers , LKML , Avi Kivity , Marcelo Tosatti , KVM , Andi Kleen , Xen Devel , Konrad Rzeszutek Wilk , Virtualization , Jeremy Fitzhardinge , Stephan Diestelhorst , Srivatsa Vaddagiri , Stefano Stabellini , Attilio Rao 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 0e4d057..5dce49d 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;