Return-path: Received: from nbd.name ([46.4.11.11]:44278 "EHLO nbd.name" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755087Ab1DJQcZ (ORCPT ); Sun, 10 Apr 2011 12:32:25 -0400 From: Felix Fietkau To: linux-wireless@vger.kernel.org Cc: linville@tuxdriver.com, ath5k-devel@lists.ath5k.org Subject: [PATCH 4/7] ath5k: optimize rx status processing Date: Sun, 10 Apr 2011 18:32:16 +0200 Message-Id: <1302453139-11437-4-git-send-email-nbd@openwrt.org> In-Reply-To: <1302453139-11437-3-git-send-email-nbd@openwrt.org> References: <1302453139-11437-1-git-send-email-nbd@openwrt.org> <1302453139-11437-2-git-send-email-nbd@openwrt.org> <1302453139-11437-3-git-send-email-nbd@openwrt.org> Sender: linux-wireless-owner@vger.kernel.org List-ID: Use ACCESS_ONCE to reduce the number of redundant loads on uncached memory Signed-off-by: Felix Fietkau --- drivers/net/wireless/ath/ath5k/desc.c | 41 ++++++++++++++------------------ 1 files changed, 18 insertions(+), 23 deletions(-) diff --git a/drivers/net/wireless/ath/ath5k/desc.c b/drivers/net/wireless/ath/ath5k/desc.c index 3758b96..e366d30 100644 --- a/drivers/net/wireless/ath/ath5k/desc.c +++ b/drivers/net/wireless/ath/ath5k/desc.c @@ -603,37 +603,37 @@ static int ath5k_hw_proc_5212_rx_status(struct ath5k_hw *ah, struct ath5k_rx_status *rs) { struct ath5k_hw_rx_status *rx_status; + u32 rxstat0, rxstat1; rx_status = &desc->ud.ds_rx.rx_stat; + rxstat1 = ACCESS_ONCE(rx_status->rx_status_1); /* No frame received / not ready */ - if (unlikely(!(rx_status->rx_status_1 & - AR5K_5212_RX_DESC_STATUS1_DONE))) + if (unlikely(!(rxstat1 & AR5K_5212_RX_DESC_STATUS1_DONE))) return -EINPROGRESS; memset(rs, 0, sizeof(struct ath5k_rx_status)); + rxstat0 = ACCESS_ONCE(rx_status->rx_status_0); /* * Frame receive status */ - rs->rs_datalen = rx_status->rx_status_0 & - AR5K_5212_RX_DESC_STATUS0_DATA_LEN; - rs->rs_rssi = AR5K_REG_MS(rx_status->rx_status_0, + rs->rs_datalen = rxstat0 & AR5K_5212_RX_DESC_STATUS0_DATA_LEN; + rs->rs_rssi = AR5K_REG_MS(rxstat0, AR5K_5212_RX_DESC_STATUS0_RECEIVE_SIGNAL); - rs->rs_rate = AR5K_REG_MS(rx_status->rx_status_0, + rs->rs_rate = AR5K_REG_MS(rxstat0, AR5K_5212_RX_DESC_STATUS0_RECEIVE_RATE); - rs->rs_antenna = AR5K_REG_MS(rx_status->rx_status_0, + rs->rs_antenna = AR5K_REG_MS(rxstat0, AR5K_5212_RX_DESC_STATUS0_RECEIVE_ANTENNA); - rs->rs_more = !!(rx_status->rx_status_0 & - AR5K_5212_RX_DESC_STATUS0_MORE); - rs->rs_tstamp = AR5K_REG_MS(rx_status->rx_status_1, + rs->rs_more = !!(rxstat0 & AR5K_5212_RX_DESC_STATUS0_MORE); + rs->rs_tstamp = AR5K_REG_MS(rxstat1, AR5K_5212_RX_DESC_STATUS1_RECEIVE_TIMESTAMP); /* * Key table status */ - if (rx_status->rx_status_1 & AR5K_5212_RX_DESC_STATUS1_KEY_INDEX_VALID) - rs->rs_keyix = AR5K_REG_MS(rx_status->rx_status_1, + if (rxstat1 & AR5K_5212_RX_DESC_STATUS1_KEY_INDEX_VALID) + rs->rs_keyix = AR5K_REG_MS(rxstat1, AR5K_5212_RX_DESC_STATUS1_KEY_INDEX); else rs->rs_keyix = AR5K_RXKEYIX_INVALID; @@ -641,27 +641,22 @@ static int ath5k_hw_proc_5212_rx_status(struct ath5k_hw *ah, /* * Receive/descriptor errors */ - if (!(rx_status->rx_status_1 & - AR5K_5212_RX_DESC_STATUS1_FRAME_RECEIVE_OK)) { - if (rx_status->rx_status_1 & - AR5K_5212_RX_DESC_STATUS1_CRC_ERROR) + if (!(rxstat1 & AR5K_5212_RX_DESC_STATUS1_FRAME_RECEIVE_OK)) { + if (rxstat1 & AR5K_5212_RX_DESC_STATUS1_CRC_ERROR) rs->rs_status |= AR5K_RXERR_CRC; - if (rx_status->rx_status_1 & - AR5K_5212_RX_DESC_STATUS1_PHY_ERROR) { + if (rxstat1 & AR5K_5212_RX_DESC_STATUS1_PHY_ERROR) { rs->rs_status |= AR5K_RXERR_PHY; - rs->rs_phyerr = AR5K_REG_MS(rx_status->rx_status_1, + rs->rs_phyerr = AR5K_REG_MS(rxstat1, AR5K_5212_RX_DESC_STATUS1_PHY_ERROR_CODE); if (!ah->ah_capabilities.cap_has_phyerr_counters) ath5k_ani_phy_error_report(ah, rs->rs_phyerr); } - if (rx_status->rx_status_1 & - AR5K_5212_RX_DESC_STATUS1_DECRYPT_CRC_ERROR) + if (rxstat1 & AR5K_5212_RX_DESC_STATUS1_DECRYPT_CRC_ERROR) rs->rs_status |= AR5K_RXERR_DECRYPT; - if (rx_status->rx_status_1 & - AR5K_5212_RX_DESC_STATUS1_MIC_ERROR) + if (rxstat1 & AR5K_5212_RX_DESC_STATUS1_MIC_ERROR) rs->rs_status |= AR5K_RXERR_MIC; } return 0; -- 1.7.3.2