On Thu, Jun 12, 2008 at 6:43 PM, Tomas Winkler <tomasw@xxxxxxxxx> wrote: > On Thu, Jun 12, 2008 at 4:54 PM, Johannes Berg > <johannes@xxxxxxxxxxxxxxxx> wrote: >> On Thu, 2008-06-12 at 09:38 -0400, Rik van Riel wrote: >>> On Thu, 12 Jun 2008 12:07:34 +0200 >>> "Zdenek Kabelac" <zdenek.kabelac@xxxxxxxxx> wrote: >>> >>> > It looks like while there was a huge amount of buffers and caches - >>> > system was unable to allocate few pages for kmalloc in iwl3945 driver >>> > after resume. >>> >>> It looks like this is because it wants to allocate 2**5 contiguous >>> pages, which is 128kB of contiguous kernel memory. >> >> 64-bit system I assume? >> The allocation should be 256 * 20 * sizeof(struct sk_buff *). > >> Try the patch below. It should improve code generation too. >> >> I discussed this with Tomas previously and he says the hw is capable of >> doing 20 fragments per frame (wonder why, Broadcom can do an unlimited >> number...) but he complained about the networking stack not being able >> to. > > This is scatter gather buffers that can be kicked in one DMA transaction. > > Well, the hardware needs to support IP checksumming for that, hence, >> afaik, only two fragments can ever be used (one for hw header, one for >> frame) > This I still don't understand why but everybody is already tired to > explaining me why.. :) Just need to find time to dig into it. > >> This cuts the allocation to 10%, or (under) a page in all cases. > > Probably. it would be safe to use vmalloc for allocating txb anyway. > I'll give it a try. So vmalloc didn't break anything on the 32bit machine I'm just about to install 64 one so it will take hour or two.. I will issue some official patch after that. > There was already discussion on LKML about memory allocation problems > on X86_64, which might explain this regression. This didn't happen > before. This is the thread title if you are interested. 'x86/kernel/pci_dma.c: gfp |= __GFP_NORETRY' Tomas -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
