Am Montag, 21. Mai 2007 23:36 schrieb David Brownell: > On Monday 21 May 2007, Oliver Neukum wrote: > > Am Mittwoch, 16. Mai 2007 16:41 schrieb David Brownell: > > > > in that when you have > > > > pre-allocated all buffers and all USB host controller descriptors, you > > > > will > > > > never get in the situation of not being able to allocate transfer > > > > descriptors > > > > on the fly, like done on Linux. > > > > > > That's not a failure mode that's been often observed on Linux. (Never, > > > in my own experience... which I admit has not focussed on that particular > > > type of stress load.) So it's hard to argue that it should motivate a > > > redesign of core APIs. > > > > We are seeing report of the networking stack exhausting the atomic > > pool. They are rare these days, but do exist. > > But transfer descriptors don't come from there.
Never, ever, even if the pool is exhausted? static struct uhci_td *uhci_alloc_td(struct uhci_hcd *uhci) { dma_addr_t dma_handle; struct uhci_td *td; td = dma_pool_alloc(uhci->td_pool, GFP_ATOMIC, &dma_handle); if (!td) return NULL; Admittedly unlikely, but impossible? Regards Oliver ------------------------------------------------------------------------- This SF.net email is sponsored by DB2 Express Download DB2 Express C - the FREE version of DB2 express and take control of your XML. No limits. Just data. Click to get it now. http://sourceforge.net/powerbar/db2/ _______________________________________________ linux-usb-devel@lists.sourceforge.net To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-devel