On 2015-12-17 11:04, Johannes Berg wrote: > On Thu, 2015-12-17 at 10:20 +0100, Janusz Dziedzic wrote: >> HW/driver should set NEED_ALIGNED4_SKBS flag in case require >> aligned skbs to four-byte boundaries. >> >> Before we have to do memmove() in the driver before >> pass this to HW and memmove() back in tx completion. >> This patch allow to save CPU and skip such memmoves. >> For each skb we called memmove(ieee80211_hdrsize()) twice. > > IMHO this is pretty awful from a code complexity POV. You also forgot > to update fast-xmit maximum header length. > > Note that we (iwlwifi) also kinda need this, but essentially solve it > with the DMA engine. Can't ath9k do the same? I tried that approach a few years ago, but it turned out to make the hardware unstable, causing random DMA lockups. - Felix -- 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
