Hi Sam, > I was able to verify that your latest patch fixes the problem with > the simul test #7, so I went ahead and committed it.
Awesome! I thought Kevin mentioned that it crashed somewhere else.. :( > > Also, when the problem actually existed, running simul #7 a bunch and > then trying to unload the kernel module was giving an error: Ah.. Maybe this was the error he mentioned to me..? > > [ 806.396608] slab error in kmem_cache_destroy(): cache > `pvfs2_op_cache': Can't free all objects > I did some debugging and it looks like the op cache entry that wasn't > getting release was from a lookup, and it looks like there's a case > where lookup can return an error that's not ENOENT, and the op entry > doesn't get released. I've attached a patch that I think fixes the > problem. Can you verify that this looks ok? Awesome! Nice catch! That looks great! > Also, I've seen this > error before on other systems (I think Pete has too) and I'm not sure > its always from this one case. Is there a good way to verify that > we're releasing ops (and possibly other cache entries) > appropriately? Just looking for ideas to harden the code in the kmod. I guess we could always keep track of extra list_head's in each object being allocated off the slab and chain it in a private global link list and verify that the list is empty prior to module unload's kmem_cache_destroy() perhaps? If not empty then free all the remaining elements.. To find out where we are leaking we could store the return address of the caller of the alloc() function in the object and use that to find out the offending leaks.. What do you think? Thanks! Murali > > -sam > > > > On Aug 16, 2007, at 12:59 PM, Murali Vilayannur wrote: > > > Kevin, > > Instead of the call to d_add(), can you replace it by a > > pvfs2_d_splice_alias() with the same parameters as before and > > recompile/reload and see if that fixes the crash. > > Something like the attached.. > > thanks, > > Murali > > > > On 8/16/07, Kevin Harms <[EMAIL PROTECTED]> wrote: > >> Murali, > >> > >> i tried the patch. (applied it to 2.6.3 source) it get > >> crashes from > >> on one of the machines. > >> i send you an email with dmesg output. > >> > >> Kevin > >> > >> <dcache.patch> > > _______________________________________________ > > Pvfs2-developers mailing list > > [email protected] > > http://www.beowulf-underground.org/mailman/listinfo/pvfs2-developers > > > > _______________________________________________ Pvfs2-developers mailing list [email protected] http://www.beowulf-underground.org/mailman/listinfo/pvfs2-developers
