Messages in this thread |  | | Date | Tue, 11 Feb 2014 04:09:16 -0800 | From | "Paul E. McKenney" <> | Subject | Re: Memory allocator semantics |
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On Tue, Feb 11, 2014 at 10:50:24AM +0200, Pekka Enberg wrote: > Hi Paul, > > On Sun, Feb 9, 2014 at 4:00 AM, Paul E. McKenney > <paulmck@linux.vnet.ibm.com> wrote: > > From what I can see, (A) works by accident, but is kind of useless because > > you allocate and free the memory without touching it. (B) and (C) are the > > lightest touches I could imagine, and as you say, both are bad. So I > > believe that it is reasonable to prohibit (A). > > > > Or is there some use for (A) that I am missing? > > So again, there's nothing in (A) that the memory allocator is > concerned about. kmalloc() makes no guarantees whatsoever about the > visibility of "r1" across CPUs. If you're saying that there's an > implicit barrier between kmalloc() and kfree(), that's an unintended > side-effect, not a design decision AFAICT.
Thank you. That was what I suspected, and I believe that it is a completely reasonable response to (A).
Thanx, Paul
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