Messages in this thread | | | Date | Tue, 13 Nov 2012 11:48:39 +0100 | From | Steffen Klassert <> | Subject | Re: [PATCH v4 3/9] net: xfrm: use __this_cpu_read per-cpu helper |
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On Tue, Nov 13, 2012 at 05:33:19PM +0800, Shan Wei wrote: > Steffen Klassert said, at 2012/11/13 15:21: > > > > This should just fetch the tfm pointer, so why exactly __this_cpu_read > > is better than __this_cpu_ptr? Please keep in mind that performance is > > not the most important thing here. It's much more important that it > > works in any case. > > [0/9] describes why we should submit this series patches. > you are not included in original mail. > > this_cpu_ptr relocates and address. this_cpu_read() relocates the address > and performs the fetch. If you want to operate on rda(defined as per_cpu) > then you can only use this_cpu_ptr. this_cpu_read() saves you more instructions > since it can do the relocation and the fetch in one instruction. >
Ok, so please add a commit message to describe your changes.
Thanks.
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