2016-05-17 12:59, Ananyev, Konstantin: > > > The rte_pktmbuf_detach() function should decrease refcnt on a direct > > > buffer. > > > > As you have noticed, "whenever the indirect buffer is detached, > > the reference counter on the direct buffer is decremented." > > So the current behaviour of rte_pktmbuf_detach() is buggy. > > Why not fix it without renaming? > > If you consider this behavioral bug is part of the API, we > > can fix it in a new function unattach and deprecate detach. > > But Konstantin, why do you want to keep a restore function? > > What is the need? > > I think it might be a useful functionality in some situations: > some users can attach/detach to external memory buffers (no mbufs) > and similar functionality is required.
Attach to external memory buffer (raw buffer) is not currently supported. > Let say right now examples/vhost/main.c has its own pktmbuf_detach_zcp() You should look at the commit http://dpdk.org/commit/68363d85 "examples/vhost: remove the non-working zero copy code" > which is doing pretty much the same - restore original values, after detaching > mbuf from external (virtio) memory buffer. > Would be good if we'll use a standard API function here. You are welcome to implement mbuf attach to raw buffer. But it is not a requirement for this fix.
