Re: [PATCH] Add a slab corruption tracepoint

[David Howells <dhowells@redhat.com>]

Vlastimil Babka <vbabka@suse.cz> wrote:

> Shouldn't that include SLUB?

I've been using SLAB.  Looking in SLUB it's much less obvious where to insert
the tracepoint.  check_bytes_and_report() maybe?

> I'm surprised to see SLAB used for debugging refcounting these days,

The refcount debugging in question is not in SLAB, but rather in rxrpc; it's
just SLAB detected the resulting memory corruption.  rxrpc has tracepoints
that track the refcounting, but SLAB printks a message to indicate the
corruption and it's a bit tricky to work out where the printk happened with
respect to the trace.

> as the SLUB debugging features are vastly superior, while SLAB ones are
> being sometimes found to be broken for years and removed.

If SLUB is better than SLAB, shouldn't SLAB be removed?

David