Return-path: Received: from mail-io0-f179.google.com ([209.85.223.179]:34599 "EHLO mail-io0-f179.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750914AbbLUSx2 (ORCPT ); Mon, 21 Dec 2015 13:53:28 -0500 Received: by mail-io0-f179.google.com with SMTP id e126so163664198ioa.1 for ; Mon, 21 Dec 2015 10:53:27 -0800 (PST) MIME-Version: 1.0 In-Reply-To: <1450344029-5296-2-git-send-email-janusz.dziedzic@tieto.com> References: <1450344029-5296-1-git-send-email-janusz.dziedzic@tieto.com> <1450344029-5296-2-git-send-email-janusz.dziedzic@tieto.com> Date: Tue, 22 Dec 2015 00:23:27 +0530 Message-ID: (sfid-20151221_195331_339312_6B04C054) Subject: Re: [RFC/RFT 2/2] ath9k: request aligned skb From: Souptick Joarder To: Janusz Dziedzic Cc: linux-wireless@vger.kernel.org, johannes@sipsolutions.net, nbd@openwrt.org Content-Type: text/plain; charset=UTF-8 Sender: linux-wireless-owner@vger.kernel.org List-ID: On Thu, Dec 17, 2015 at 2:50 PM, Janusz Dziedzic wrote: > > Set NEEDS_ALIGNED4_SKB hw flag. > This allow driver to save CPU and remove two memmove > from tx path. > > Signed-off-by: Janusz Dziedzic > --- > drivers/net/wireless/ath/ath9k/init.c | 1 + > drivers/net/wireless/ath/ath9k/xmit.c | 15 ++++++++++----- > 2 files changed, 11 insertions(+), 5 deletions(-) > > diff --git a/drivers/net/wireless/ath/ath9k/init.c b/drivers/net/wireless/ath/ath9k/init.c > index 6abace6..d578a00 100644 > --- a/drivers/net/wireless/ath/ath9k/init.c > +++ b/drivers/net/wireless/ath/ath9k/init.c > @@ -831,6 +831,7 @@ static void ath9k_set_hw_capab(struct ath_softc *sc, struct ieee80211_hw *hw) > ieee80211_hw_set(hw, RX_INCLUDES_FCS); > ieee80211_hw_set(hw, HOST_BROADCAST_PS_BUFFERING); > ieee80211_hw_set(hw, SUPPORT_FAST_XMIT); > + ieee80211_hw_set(hw, NEEDS_ALIGNED4_SKBS); > > if (ath9k_ps_enable) > ieee80211_hw_set(hw, SUPPORTS_PS); > diff --git a/drivers/net/wireless/ath/ath9k/xmit.c b/drivers/net/wireless/ath/ath9k/xmit.c > index 82fc76f..c3bd1b1 100644 > --- a/drivers/net/wireless/ath/ath9k/xmit.c > +++ b/drivers/net/wireless/ath/ath9k/xmit.c > @@ -2267,11 +2267,15 @@ static int ath_tx_prepare(struct ieee80211_hw *hw, struct sk_buff *skb, > padpos = ieee80211_hdrlen(hdr->frame_control); > padsize = padpos & 3; > if (padsize && skb->len > padpos) { > - if (skb_headroom(skb) < padsize) > - return -ENOMEM; > + if (ieee80211_hw_check(hw, NEEDS_ALIGNED4_SKBS)) { > + frmlen -= padsize; > + } else { > + if (skb_headroom(skb) < padsize) > + return -ENOMEM; > > - skb_push(skb, padsize); > - memmove(skb->data, skb->data + padsize, padpos); why the same lines has been removed and added again ? > + skb_push(skb, padsize); > + memmove(skb->data, skb->data + padsize, padpos); > + } > } > > > setup_frame_info(hw, sta, skb, frmlen); > @@ -2494,7 +2498,8 @@ static void ath_tx_complete(struct ath_softc *sc, struct sk_buff *skb, > > padpos = ieee80211_hdrlen(hdr->frame_control); > padsize = padpos & 3; > - if (padsize && skb->len>padpos+padsize) { > + if (padsize && skb->len > padpos + padsize && > + !ieee80211_hw_check(sc->hw, NEEDS_ALIGNED4_SKBS)) { > /* > * Remove MAC header padding before giving the frame back to > * mac80211. > -- > 1.9.1 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-wireless" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html Regards Souptick