Messages in this thread | | | Subject | Re: [PATCH 12/30] mm: memory reserve management | From | Peter Zijlstra <> | Date | Mon, 28 Jul 2008 12:39:01 +0200 |
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On Mon, 2008-07-28 at 13:29 +0300, Pekka Enberg wrote:
> > > > + } > > > > + > > > > + obj = __kmalloc_node_track_caller(size, flags, node, ip); > > > > + WARN_ON(!obj); > > > > > > Why don't we discharge from the reserve here if !obj? > > > > Well, this allocation should never fail: > > - we reserved memory > > - we accounted/throttle its usage > > > > Thus this allocation should always succeed. > > But if it *does* fail, it doesn't help that we mess up the reservation > counts, no?
I guess you're right there. Will fix. Thanks!
> > > > +{ > > > > + size_t size = ksize(obj); > > > > + > > > > + kfree(obj); > > > > > > We're trying to get rid of kfree() so I'd __kfree_reserve() could to > > > mm/sl?b.c. Matt, thoughts? > > > > My issue with moving these helpers into mm/sl?b.c is that it would > > require replicating all this code 3 times. Even though the functionality > > is (or should) be invariant to the actual slab implementation. > > Right, I guess we could just rename ksize() to something else then and > keep it internal to mm/.
That would be nice - we can stuff it into mm/internal.h or somesuch.
Also, you might have noticed, I still need to do everything SLOB. The last time I rewrote all this code I was still hoping Linux would 'soon' have a single slab allocator, but evidently we're still going with 3 for now.. :-/
So I guess I can no longer hide behind that and will have to bite the bullet and write the SLOB bits..
> > > > + /* > > > > + * ksize gives the full allocated size vs the requested size we used to > > > > + * charge; however since we round up to the nearest power of two, this > > > > + * should all work nicely. > > > > + */ > > > > + mem_reserve_kmalloc_charge(res, -size); > > > > +}
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