Le vendredi 07 janvier 2011 Ã 12:09 -0800, Luis R. Rodriguez a Ãcrit : > On Fri, Jan 07, 2011 at 10:34:52AM -0800, Ben Greear wrote: > > On 01/07/2011 02:58 AM, Johannes Berg wrote: > > > On Thu, 2011-01-06 at 16:46 -0800, greearb@xxxxxxxxxxxxxxx wrote: > > >> From: Ben Greear<greearb@xxxxxxxxxxxxxxx> > > >> > > >> Patch is from Eric Dumazet, as described here: > > >> https://patchwork.kernel.org/patch/104271/ > > >> > > >> Reported-by: Michael Guntsche<mike@xxxxxxxxxxxx> > > >> Signed-off-by: Eric Dumazet<eric.dumazet@xxxxxxxxx> > > >> Signed-off-by: Ben Greear<greearb@xxxxxxxxxxxxxxx> > > >> --- > > >> > > >> NOTE: This needs review by ath9k and/or other informed > > >> people. > > > > > > This doesn't make sense. It might help, but it'll probably lead to not > > > being able to receive all frames off the air. > > > > > > If this is an issue, ath9k should do paged RX like iwlwifi. > > > > Ok, I backed this out..but now I'm back to getting buffer allocation > > failures (and this is on a system with 2GB RAM). > > > > Seems it's coming from mac80211 instead of ath9k, at least most of > > the time (I'm using 60 stations, so it probably needs to make lots of > > copies in the rx path). The traffic I'm generating/receiving is 1024 byte UDP > > payloads. > > > > Does this mean I really received a packet that was 3872 bytes long, > > or is the skb_copy allocating/copying empty data? > > Good question. The buffer we setup for DMA should be large since we > need to support AMSDU RX up to a certain bytes of RX data for the frame. > Harwdware should tell us the right size for the RX'd data and the skb > should be set with that size, respectively. Following this logic, > skb_copy() should only allocate on the order of the required skb->len. > > Remember that trick we did to force the older memory leak issues by > forcing an skb_copy() on every RX'd frame and then just discarding that > buffer immediately? You can try to do the same and print the skb->len > there, just to check what's going on. Using skb_copy() is wrong then, since it makes a copy (order-1 allocations) It should use : skb_alloc( actual_size_of_frame not the 3840 thing ...) copy(data) -- 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
