On Wed, 31 Oct 2012, Shan Wei wrote: > --- a/net/openvswitch/datapath.c > +++ b/net/openvswitch/datapath.c > @@ -208,7 +208,7 @@ void ovs_dp_process_received_packet(struct vport *p, > struct sk_buff *skb) > int error; > int key_len; > > - stats = per_cpu_ptr(dp->stats_percpu, smp_processor_id()); > + stats = this_cpu_ptr(dp->stats_percpu);
Well this is an improvement and may be ok if the preemption is disabled at this point. There is another possibility here to use this_cpu_read/add/inc instead of determining the pointer to the local cpu first and then performing operations on the fields. The pointer relocation with this_cpu_xxx ops is implicit in the instructions and safe against changing of processors. It would also save us the determination of a pointer to the current cpus stats structure. _______________________________________________ dev mailing list dev@openvswitch.org http://openvswitch.org/mailman/listinfo/dev
