Messages in this thread | | | Date | Mon, 2 Mar 2015 08:58:12 -0800 | From | "Paul E. McKenney" <> | Subject | Re: [RFC][PATCH] module: Optimize __module_address() using a latched RB-tree |
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On Mon, Mar 02, 2015 at 10:24:40AM +0100, Peter Zijlstra wrote: > On Sat, Feb 28, 2015 at 03:32:03PM -0800, Paul E. McKenney wrote: > > Whew! > > > > Though otherwise whatever you were doing would have been pretty cool > > and fun to learn about. ;-) > > So I think I can do that; where readers and writers are fully separated, > but it requires: > > - tripple latch > - copy operator > - nested RCU > > And the result would be horribly expensive (mostly due to the copy > operator on dynamic data structures) on the update side, which severely > limits the applicability of the scheme.
True enough, if you have a single pointer to an RCU-protected data structure, you can update anything in any way by doing a deep copy of the original, updating, and swapping pointers. And what is a little copy overhead among friends? ;-)
Thanx, Paul
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