Messages in this thread | | | Date | Wed, 23 Feb 2011 11:39:33 -0800 | From | "Paul E. McKenney" <> | Subject | Re: [PATCH RFC tip/core/rcu 11/11] rcu: move TREE_RCU from softirq to kthread |
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On Wed, Feb 23, 2011 at 01:22:02PM -0600, Christoph Lameter wrote: > On Wed, 23 Feb 2011, Paul E. McKenney wrote: > > > These do introduce redundant preempt_disable()/preempt_enable() calls, but > > this is not on a fastpath, so should be OK, and the improved readability > > is certainly nice. The read and the write do need to happen on the same > > CPU, FWIW. > > this_cpu_xxx only use preempt_enable/disable() on platforms that do not > support per cpu atomic instructions. On x86 no preempt enable/disable will > be inserted. > > You can also use the __this_cpu_xxx operations which never add preempt > disable/enable because they expect the caller to deal with preemption.
Those make a lot of sense in this case, as I need to use __get_cpu_var() anyway.
Thank you for all the info!
Thanx, Paul
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