On Fri, Oct 27, 2017 at 3:22 PM, Subash Abhinov Kasiviswanathan <subas...@codeaurora.org> wrote: >> This doesn't make sense to me, maybe I am missing something. What >> "real device" is setting the skb->destructor() and doing it to somehow >> handle recycling? The only driver I can find that is setting >> skb->desctructor() is the Chelsio drivers, and they appear to be using >> it to just clean-up DMA mappings in their transmit path. >> >> Thanks. >> >> - Alex > > > Hi Alex > > The real device will have a pool of skbs and mark them as unused on > initialization. It will use these skbs to copy data from hardware and > pass them onto rmnet after marking them as used. Once rmnet is done > processing, the callback of the real device set in the skb_destructor > is invoked and the skb is set as unused and can be used again for > copying data.
There is a pretty big difference between calling skb->destructor() and freeing the buffer. My concern would be how do you deal with the reference count issues that is going to bring up? > There are no drivers setting the skb->destructor() in receive path > upstream as of now but the plan is to get them there. Okay. Got it. Thanks. - Alex
