With this change, less CPU time is spent trying to look for consecutive
pages for rx skbs. This also reduces the socket memory required for IP/UDP
reassembly.
Only two buffers per frame are supported. Frames spanning more buffers
will be dropped, but the buffer size is enough to handle the required
AMSDU size.
Signed-off-by: Jouni Malinen <[email protected]>
Signed-off-by: Felix Fietkau <[email protected]>
---
drivers/net/wireless/ath/ath9k/ath9k.h | 2 +
drivers/net/wireless/ath/ath9k/main.c | 5 ++
drivers/net/wireless/ath/ath9k/recv.c | 88 +++++++++++++++++++++++---------
3 files changed, 71 insertions(+), 24 deletions(-)
diff --git a/drivers/net/wireless/ath/ath9k/ath9k.h b/drivers/net/wireless/ath/ath9k/ath9k.h
index eb89ecd..37c188c 100644
--- a/drivers/net/wireless/ath/ath9k/ath9k.h
+++ b/drivers/net/wireless/ath/ath9k/ath9k.h
@@ -311,6 +311,8 @@ struct ath_rx {
struct ath_descdma rxdma;
struct ath_buf *rx_bufptr;
struct ath_rx_edma rx_edma[ATH9K_RX_QUEUE_MAX];
+
+ struct sk_buff *frag;
};
int ath_startrecv(struct ath_softc *sc);
diff --git a/drivers/net/wireless/ath/ath9k/main.c b/drivers/net/wireless/ath/ath9k/main.c
index 9157dbc..e912e63 100644
--- a/drivers/net/wireless/ath/ath9k/main.c
+++ b/drivers/net/wireless/ath/ath9k/main.c
@@ -1294,6 +1294,11 @@ static void ath9k_stop(struct ieee80211_hw *hw)
} else
sc->rx.rxlink = NULL;
+ if (sc->rx.frag) {
+ dev_kfree_skb_any(sc->rx.frag);
+ sc->rx.frag = NULL;
+ }
+
/* disable HAL and put h/w to sleep */
ath9k_hw_disable(ah);
ath9k_hw_configpcipowersave(ah, 1, 1);
diff --git a/drivers/net/wireless/ath/ath9k/recv.c b/drivers/net/wireless/ath/ath9k/recv.c
index b2b12a2..daf171d 100644
--- a/drivers/net/wireless/ath/ath9k/recv.c
+++ b/drivers/net/wireless/ath/ath9k/recv.c
@@ -209,11 +209,6 @@ static int ath_rx_edma_init(struct ath_softc *sc, int nbufs)
int error = 0, i;
u32 size;
-
- common->rx_bufsize = roundup(IEEE80211_MAX_MPDU_LEN +
- ah->caps.rx_status_len,
- min(common->cachelsz, (u16)64));
-
ath9k_hw_set_rx_bufsize(ah, common->rx_bufsize -
ah->caps.rx_status_len);
@@ -300,12 +295,12 @@ int ath_rx_init(struct ath_softc *sc, int nbufs)
sc->sc_flags &= ~SC_OP_RXFLUSH;
spin_lock_init(&sc->rx.rxbuflock);
+ common->rx_bufsize = IEEE80211_MAX_MPDU_LEN / 2 +
+ sc->sc_ah->caps.rx_status_len;
+
if (sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_EDMA) {
return ath_rx_edma_init(sc, nbufs);
} else {
- common->rx_bufsize = roundup(IEEE80211_MAX_MPDU_LEN,
- min(common->cachelsz, (u16)64));
-
ath_dbg(common, ATH_DBG_CONFIG, "cachelsz %u rxbufsize %u\n",
common->cachelsz, common->rx_bufsize);
@@ -815,15 +810,9 @@ static bool ath9k_rx_accept(struct ath_common *common,
if (rx_stats->rs_datalen > (common->rx_bufsize - rx_status_len))
return false;
- /*
- * rs_more indicates chained descriptors which can be used
- * to link buffers together for a sort of scatter-gather
- * operation.
- * reject the frame, we don't support scatter-gather yet and
- * the frame is probably corrupt anyway
- */
+ /* Only use error bits from the last fragment */
if (rx_stats->rs_more)
- return false;
+ return true;
/*
* The rx_stats->rs_status will not be set until the end of the
@@ -981,6 +970,10 @@ static int ath9k_rx_skb_preprocess(struct ath_common *common,
if (!ath9k_rx_accept(common, hdr, rx_status, rx_stats, decrypt_error))
return -EINVAL;
+ /* Only use status info from the last fragment */
+ if (rx_stats->rs_more)
+ return 0;
+
ath9k_process_rssi(common, hw, hdr, rx_stats);
if (ath9k_process_rate(common, hw, rx_stats, rx_status))
@@ -1582,7 +1575,7 @@ div_comb_done:
int ath_rx_tasklet(struct ath_softc *sc, int flush, bool hp)
{
struct ath_buf *bf;
- struct sk_buff *skb = NULL, *requeue_skb;
+ struct sk_buff *skb = NULL, *requeue_skb, *hdr_skb;
struct ieee80211_rx_status *rxs;
struct ath_hw *ah = sc->sc_ah;
struct ath_common *common = ath9k_hw_common(ah);
@@ -1633,8 +1626,17 @@ int ath_rx_tasklet(struct ath_softc *sc, int flush, bool hp)
if (!skb)
continue;
- hdr = (struct ieee80211_hdr *) (skb->data + rx_status_len);
- rxs = IEEE80211_SKB_RXCB(skb);
+ /*
+ * Take frame header from the first fragment and RX status from
+ * the last one.
+ */
+ if (sc->rx.frag)
+ hdr_skb = sc->rx.frag;
+ else
+ hdr_skb = skb;
+
+ hdr = (struct ieee80211_hdr *) (hdr_skb->data + rx_status_len);
+ rxs = IEEE80211_SKB_RXCB(hdr_skb);
ath_debug_stat_rx(sc, &rs);
@@ -1643,12 +1645,12 @@ int ath_rx_tasklet(struct ath_softc *sc, int flush, bool hp)
* chain it back at the queue without processing it.
*/
if (flush)
- goto requeue;
+ goto requeue_drop_frag;
retval = ath9k_rx_skb_preprocess(common, hw, hdr, &rs,
rxs, &decrypt_error);
if (retval)
- goto requeue;
+ goto requeue_drop_frag;
rxs->mactime = (tsf & ~0xffffffffULL) | rs.rs_tstamp;
if (rs.rs_tstamp > tsf_lower &&
@@ -1668,7 +1670,7 @@ int ath_rx_tasklet(struct ath_softc *sc, int flush, bool hp)
* skb and put it at the tail of the sc->rx.rxbuf list for
* processing. */
if (!requeue_skb)
- goto requeue;
+ goto requeue_drop_frag;
/* Unmap the frame */
dma_unmap_single(sc->dev, bf->bf_buf_addr,
@@ -1679,8 +1681,9 @@ int ath_rx_tasklet(struct ath_softc *sc, int flush, bool hp)
if (ah->caps.rx_status_len)
skb_pull(skb, ah->caps.rx_status_len);
- ath9k_rx_skb_postprocess(common, skb, &rs,
- rxs, decrypt_error);
+ if (!rs.rs_more)
+ ath9k_rx_skb_postprocess(common, hdr_skb, &rs,
+ rxs, decrypt_error);
/* We will now give hardware our shiny new allocated skb */
bf->bf_mpdu = requeue_skb;
@@ -1697,6 +1700,38 @@ int ath_rx_tasklet(struct ath_softc *sc, int flush, bool hp)
break;
}
+ if (rs.rs_more) {
+ /*
+ * rs_more indicates chained descriptors which can be
+ * used to link buffers together for a sort of
+ * scatter-gather operation.
+ */
+ if (sc->rx.frag) {
+ /* too many fragments - cannot handle frame */
+ dev_kfree_skb_any(sc->rx.frag);
+ dev_kfree_skb_any(skb);
+ skb = NULL;
+ }
+ sc->rx.frag = skb;
+ goto requeue;
+ }
+
+ if (sc->rx.frag) {
+ int space = skb->len - skb_tailroom(hdr_skb);
+
+ sc->rx.frag = NULL;
+
+ if (pskb_expand_head(hdr_skb, 0, space, GFP_ATOMIC) < 0) {
+ dev_kfree_skb(skb);
+ goto requeue_drop_frag;
+ }
+
+ skb_copy_from_linear_data(skb, skb_put(hdr_skb, skb->len),
+ skb->len);
+ dev_kfree_skb_any(skb);
+ skb = hdr_skb;
+ }
+
/*
* change the default rx antenna if rx diversity chooses the
* other antenna 3 times in a row.
@@ -1722,6 +1757,11 @@ int ath_rx_tasklet(struct ath_softc *sc, int flush, bool hp)
ieee80211_rx(hw, skb);
+requeue_drop_frag:
+ if (sc->rx.frag) {
+ dev_kfree_skb_any(sc->rx.frag);
+ sc->rx.frag = NULL;
+ }
requeue:
if (edma) {
list_add_tail(&bf->list, &sc->rx.rxbuf);
--
1.7.3.2
On Wed, Jan 26, 2011 at 06:23:27PM +0100, Felix Fietkau wrote:
> With this change, less CPU time is spent trying to look for consecutive
> pages for rx skbs. This also reduces the socket memory required for IP/UDP
> reassembly.
> Only two buffers per frame are supported. Frames spanning more buffers
> will be dropped, but the buffer size is enough to handle the required
> AMSDU size.
>
> Signed-off-by: Jouni Malinen <[email protected]>
> Signed-off-by: Felix Fietkau <[email protected]>
Will this address https://bugzilla.kernel.org/show_bug.cgi?id=26652 ?
John
--
John W. Linville Someday the world will need a hero, and you
[email protected] might be all we have. Be ready.
On 2011-01-27 10:31 PM, John W. Linville wrote:
> On Wed, Jan 26, 2011 at 06:23:27PM +0100, Felix Fietkau wrote:
>> With this change, less CPU time is spent trying to look for consecutive
>> pages for rx skbs. This also reduces the socket memory required for IP/UDP
>> reassembly.
>> Only two buffers per frame are supported. Frames spanning more buffers
>> will be dropped, but the buffer size is enough to handle the required
>> AMSDU size.
>>
>> Signed-off-by: Jouni Malinen <[email protected]>
>> Signed-off-by: Felix Fietkau <[email protected]>
>
> Will this address https://bugzilla.kernel.org/show_bug.cgi?id=26652 ?
I think so. Memory allocation will fail less frequently and it reduces
RAM usage per device by 2 MB.
- Felix