Ming Lei wrote: > 2010/4/6 Sujith <Sujith.Manoharan@xxxxxxxxxxx>: > > Use a spin lock to prevent concurrent access > > to variables dealing with RX stream mode handling. > > which variables are needed to be protected? > > It seems hif_dev->rx_transfer_len, hif_dev->remain_skb > and hif_dev->rx_pkt_len are only accessed in ath9k_hif_usb_rx_stream, > which is only called in hard irq(urb->complete) context and now is > serialized strictly, so the protection is useless, isn't it? On a SMP machine, the RX callback can run on two CPUs, in this case, appropriate protection is needed between the two hard-irq handlers. > > Currently, no protection is implemented - which > > causes problems in RX. > > which problems? Could you describe them in detail? The RX stream position-hooks would get mangled up if two IRQ handlers access them without any kind of protection. This corrupts the stream data - causing data loss. Sujith -- 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
