On Wed, Oct 02, 2013 at 04:33:47PM +0100, Bird, Tim wrote: > On Wednesday, October 02, 2013 7:41 AM, Christoph Lameter [cl@xxxxxxxxx] wrote: > > > >On Fri, 27 Sep 2013, Frank Rowand wrote: > > > >> Move the kmemleak code for small block allocation out from > >> under CONFIG_SLUB_DEBUG. > > > >Well in that case it may be better to move the hooks as a whole out of > >the CONFIG_SLUB_DEBUG section. Do the #ifdeffering for each call from the > >hooks instead. > > > >The point of the hook functions is to separate the hooks out of the > >functions so taht they do not accumulate in the main code. > > > >The patch moves one hook back into the main code. Please keep the checks > >in the hooks. > > Thanks for the feedback. Roman's first patch, which we discussed internally > before sending this one, did exactly that. I guess Roman gets to say "I told > you so." :-) My bad for telling him to change it. > > We'll refactor along the lines that you describe, and send another one. > > The problem child is actually the unconditional call to kmemleak_alloc() > in kmalloc_large_node() (in slub.c). The problem comes because that call > is unconditional on CONFIG_SLUB_DEBUG but the kmemleak > calls in the hook routines are conditional on CONFIG_SLUB_DEBUG. > So if you have CONFIG_SLUB_DEBUG=n but CONFIG_DEBUG_KMEMLEAK=y, > you get the false reports. > > Now, there are kmemleak calls in kmalloc_large_node() and kfree() that don't > follow the "hook" pattern. Should these be moved to 'hook' routines, to keep > all the checks in the hooks? > > Personally, I like the idea of keeping bookeeping/tracing/debug stuff in hook > routines. I also like de-coupling CONFIG_SLUB_DEBUG and CONFIG_DEBUG_KMEMLEAK, > but maybe others have a different opinon. Unless someone speaks up, we'll > move the the currently in-function kmemleak calls into hooks, and all of the > kmemleak stuff out from under CONFIG_SLUB_DEBUG. > We'll have to see if the ifdefs get a little messy. Kmemleak doesn't depend on SLUB_DEBUG (at least it didn't originally ;), so I don't think we should add an artificial dependency (or select). Can we have kmemleak_*() calls in both debug and !debug hooks? -- Catalin -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>