Messages in this thread | | | Date | Wed, 02 Apr 2014 16:38:47 -0400 | From | Waiman Long <> | Subject | Re: [PATCH v8 10/10] pvqspinlock, x86: Enable qspinlock PV support for XEN |
| |
On 04/02/2014 10:39 AM, Konrad Rzeszutek Wilk wrote: >> diff --git a/kernel/Kconfig.locks b/kernel/Kconfig.locks >> index a70fdeb..451e392 100644 >> --- a/kernel/Kconfig.locks >> +++ b/kernel/Kconfig.locks >> @@ -229,4 +229,4 @@ config ARCH_USE_QUEUE_SPINLOCK >> >> config QUEUE_SPINLOCK >> def_bool y if ARCH_USE_QUEUE_SPINLOCK >> - depends on SMP&& (!PARAVIRT_SPINLOCKS || !XEN) >> + depends on SMP > If I read this correctly that means you cannot select any more the old > ticketlocks? As in, if you select CONFIG_PARAVIRT on X86 it will automatically > select ARCH_USE_QUEUE_SPINLOCK which will then enable this by default? > > Should the 'def_bool' be selectable?
My initial qspinlock patch allows it to be selectable, but there was comment that doing so would increase the testing matrix and so made it less desirable. That was why I made it the default for 64-bit code which are more likely to be used in large machines which benefit the most from this patch. 32-bit kernel will still use the ticket lock.
-Longman
| |