Messages in this thread | | | Subject | Re: [PATCH v2] xen/spinlock: Don't use pvqspinlock if only 1 vCPU | From | Boris Ostrovsky <> | Date | Tue, 31 Jul 2018 13:05:39 -0400 |
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On 07/19/2018 05:39 PM, Waiman Long wrote: > On a VM with only 1 vCPU, the locking fast paths will always be > successful. In this case, there is no need to use the the PV qspinlock > code which has higher overhead on the unlock side than the native > qspinlock code. > > The xen_pvspin veriable is also turned off in this 1 vCPU case to > eliminate unneeded pvqspinlock initialization in xen_init_lock_cpu() > which is run after xen_init_spinlocks(). > > Signed-off-by: Waiman Long <longman@redhat.com>
Applied to for-linus-4.19.
-boris
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