HW reports each A-MSDU subframe as a separate
sk_buff. It is impossible to configure it to
behave differently.
Until now ath10k was reconstructing A-MSDUs from
subframes which involved a lot of memory
operations. This proved to be a significant
contributor to degraded RX performance.
Signed-off-by: Michal Kazior <michal.kazior@xxxxxxxxx>
---
drivers/net/wireless/ath/ath10k/htt_rx.c | 204 ++++++++++++------------------
drivers/net/wireless/ath/ath10k/txrx.c | 2 +
2 files changed, 83 insertions(+), 123 deletions(-)
diff --git a/drivers/net/wireless/ath/ath10k/htt_rx.c b/drivers/net/wireless/ath/ath10k/htt_rx.c
index 62ea9c8..f79f815 100644
--- a/drivers/net/wireless/ath/ath10k/htt_rx.c
+++ b/drivers/net/wireless/ath/ath10k/htt_rx.c
@@ -41,6 +41,10 @@
/* when under memory pressure rx ring refill may fail and needs a retry */
#define HTT_RX_RING_REFILL_RETRY_MS 50
+
+static int ath10k_htt_rx_get_csum_state(struct sk_buff *skb);
+
+
static int ath10k_htt_rx_ring_size(struct ath10k_htt *htt)
{
int size;
@@ -591,136 +595,109 @@ static bool ath10k_htt_rx_hdr_is_amsdu(struct ieee80211_hdr *hdr)
return false;
}
-static int ath10k_htt_rx_amsdu(struct ath10k_htt *htt,
- struct htt_rx_info *info)
+struct rfc1042_hdr {
+ u8 llc_dsap;
+ u8 llc_ssap;
+ u8 llc_ctrl;
+ u8 snap_oui[3];
+ __be16 snap_type;
+} __packed;
+
+struct amsdu_subframe_hdr {
+ u8 dst[ETH_ALEN];
+ u8 src[ETH_ALEN];
+ __be16 len;
+} __packed;
+
+static void ath10k_htt_rx_amsdu(struct ath10k_htt *htt,
+ struct htt_rx_info *info)
{
struct htt_rx_desc *rxd;
- struct sk_buff *amsdu;
struct sk_buff *first;
- struct ieee80211_hdr *hdr;
struct sk_buff *skb = info->skb;
enum rx_msdu_decap_format fmt;
enum htt_rx_mpdu_encrypt_type enctype;
+ struct ieee80211_hdr *hdr;
+ u8 hdr_buf[64];
unsigned int hdr_len;
- int crypto_len;
rxd = (void *)skb->data - sizeof(*rxd);
- fmt = MS(__le32_to_cpu(rxd->msdu_start.info1),
- RX_MSDU_START_INFO1_DECAP_FORMAT);
enctype = MS(__le32_to_cpu(rxd->mpdu_start.info0),
RX_MPDU_START_INFO0_ENCRYPT_TYPE);
- /* FIXME: No idea what assumptions are safe here. Need logs */
- if ((fmt == RX_MSDU_DECAP_RAW && skb->next)) {
- ath10k_htt_rx_free_msdu_chain(skb->next);
- skb->next = NULL;
- return -ENOTSUPP;
- }
+ hdr = (struct ieee80211_hdr *)rxd->rx_hdr_status;
+ hdr_len = ieee80211_hdrlen(hdr->frame_control);
+ memcpy(hdr_buf, hdr, hdr_len);
+ hdr = (struct ieee80211_hdr *)hdr_buf;
- /* A-MSDU max is a little less than 8K */
- amsdu = dev_alloc_skb(8*1024);
- if (!amsdu) {
- ath10k_warn("A-MSDU allocation failed\n");
- ath10k_htt_rx_free_msdu_chain(skb->next);
- skb->next = NULL;
- return -ENOMEM;
- }
-
- if (fmt >= RX_MSDU_DECAP_NATIVE_WIFI) {
- int hdrlen;
-
- hdr = (void *)rxd->rx_hdr_status;
- hdrlen = ieee80211_hdrlen(hdr->frame_control);
- memcpy(skb_put(amsdu, hdrlen), hdr, hdrlen);
- }
+ /* FIXME: Hopefully this is a temporary measure.
+ *
+ * Reporting individual A-MSDU subframes means each reported frame
+ * shares the same sequence number.
+ *
+ * mac80211 drops frames it recognizes as duplicates, i.e.
+ * retransmission flag is set and sequence number matches sequence
+ * number from a previous frame (as per IEEE 802.11-2012: 9.3.2.10
+ * "Duplicate detection and recovery")
+ *
+ * To avoid frames being dropped clear retransmission flag for all
+ * received A-MSDUs.
+ *
+ * Worst case: actual duplicate frames will be reported but this should
+ * still be handled gracefully by other OSI/ISO layers. */
+ hdr->frame_control &= cpu_to_le16(~IEEE80211_FCTL_RETRY);
first = skb;
while (skb) {
void *decap_hdr;
- int decap_len = 0;
+ int decap_len;
rxd = (void *)skb->data - sizeof(*rxd);
fmt = MS(__le32_to_cpu(rxd->msdu_start.info1),
- RX_MSDU_START_INFO1_DECAP_FORMAT);
+ RX_MSDU_START_INFO1_DECAP_FORMAT);
decap_hdr = (void *)rxd->rx_hdr_status;
- if (skb == first) {
- /* We receive linked A-MSDU subframe skbuffs. The
- * first one contains the original 802.11 header (and
- * possible crypto param) in the RX descriptor. The
- * A-MSDU subframe header follows that. Each part is
- * aligned to 4 byte boundary. */
-
- hdr = (void *)amsdu->data;
- hdr_len = ieee80211_hdrlen(hdr->frame_control);
- crypto_len = ath10k_htt_rx_crypto_param_len(enctype);
-
- decap_hdr += roundup(hdr_len, 4);
- decap_hdr += roundup(crypto_len, 4);
- }
-
- /* When fmt == RX_MSDU_DECAP_8023_SNAP_LLC:
- *
- * SNAP 802.3 consists of:
- * [dst:6][src:6][len:2][dsap:1][ssap:1][ctl:1][snap:5]
- * [data][fcs:4].
- *
- * Since this overlaps with A-MSDU header (da, sa, len)
- * there's nothing extra to do. */
-
- if (fmt == RX_MSDU_DECAP_ETHERNET2_DIX) {
- /* Ethernet2 decap inserts ethernet header in place of
- * A-MSDU subframe header. */
- skb_pull(skb, 6 + 6 + 2);
-
- /* A-MSDU subframe header length */
- decap_len += 6 + 6 + 2;
-
- /* Ethernet2 decap also strips the LLC/SNAP so we need
- * to re-insert it. The LLC/SNAP follows A-MSDU
- * subframe header. */
- /* FIXME: Not all LLCs are 8 bytes long */
- decap_len += 8;
-
- memcpy(skb_put(amsdu, decap_len), decap_hdr, decap_len);
- }
+ skb->ip_summed = ath10k_htt_rx_get_csum_state(skb);
- if (fmt == RX_MSDU_DECAP_NATIVE_WIFI) {
- /* Native Wifi decap inserts regular 802.11 header
- * in place of A-MSDU subframe header. */
- hdr = (struct ieee80211_hdr *)skb->data;
- skb_pull(skb, ieee80211_hdrlen(hdr->frame_control));
-
- /* A-MSDU subframe header length */
- decap_len += 6 + 6 + 2;
-
- memcpy(skb_put(amsdu, decap_len), decap_hdr, decap_len);
+ /* First frame in an A-MSDU chain has more decapped data. */
+ if (skb == first) {
+ decap_hdr += round_up(ieee80211_hdrlen(hdr->frame_control), 4);
+ decap_hdr += round_up(ath10k_htt_rx_crypto_param_len(enctype), 4);
}
- if (fmt == RX_MSDU_DECAP_RAW)
- skb_trim(skb, skb->len - 4); /* remove FCS */
-
- memcpy(skb_put(amsdu, skb->len), skb->data, skb->len);
-
- /* A-MSDU subframes are padded to 4bytes
- * but relative to first subframe, not the whole MPDU */
- if (skb->next && ((decap_len + skb->len) & 3)) {
- int padlen = 4 - ((decap_len + skb->len) & 3);
- memset(skb_put(amsdu, padlen), 0, padlen);
+ switch (fmt) {
+ case RX_MSDU_DECAP_RAW:
+ skb_trim(skb, skb->len - FCS_LEN);
+ break;
+ case RX_MSDU_DECAP_NATIVE_WIFI:
+ break;
+ case RX_MSDU_DECAP_ETHERNET2_DIX:
+ decap_len = 0;
+ decap_len += sizeof(struct rfc1042_hdr);
+ decap_len += sizeof(struct amsdu_subframe_hdr);
+
+ skb_pull(skb, sizeof(struct ethhdr));
+ memcpy(skb_push(skb, decap_len), decap_hdr, decap_len);
+ memcpy(skb_push(skb, hdr_len), hdr, hdr_len);
+ break;
+ case RX_MSDU_DECAP_8023_SNAP_LLC:
+ memcpy(skb_push(skb, hdr_len), hdr, hdr_len);
+ break;
}
+ info->skb = skb;
+ info->encrypt_type = enctype;
skb = skb->next;
- }
-
- info->skb = amsdu;
- info->encrypt_type = enctype;
+ info->skb->next = NULL;
- ath10k_htt_rx_free_msdu_chain(first);
+ ath10k_process_rx(htt->ar, info);
+ }
- return 0;
+ /* FIXME: It might be nice to re-assemble the A-MSDU when there's a
+ * monitor interface active for sniffing purposes. */
}
-static int ath10k_htt_rx_msdu(struct ath10k_htt *htt, struct htt_rx_info *info)
+static void ath10k_htt_rx_msdu(struct ath10k_htt *htt, struct htt_rx_info *info)
{
struct sk_buff *skb = info->skb;
struct htt_rx_desc *rxd;
@@ -742,6 +719,8 @@ static int ath10k_htt_rx_msdu(struct ath10k_htt *htt, struct htt_rx_info *info)
RX_MPDU_START_INFO0_ENCRYPT_TYPE);
hdr = (void *)skb->data - RX_HTT_HDR_STATUS_LEN;
+ skb->ip_summed = ath10k_htt_rx_get_csum_state(skb);
+
switch (fmt) {
case RX_MSDU_DECAP_RAW:
/* remove trailing FCS */
@@ -782,7 +761,8 @@ static int ath10k_htt_rx_msdu(struct ath10k_htt *htt, struct htt_rx_info *info)
info->skb = skb;
info->encrypt_type = enctype;
- return 0;
+
+ ath10k_process_rx(htt->ar, info);
}
static bool ath10k_htt_rx_has_decrypt_err(struct sk_buff *skb)
@@ -854,8 +834,6 @@ static void ath10k_htt_rx_handler(struct ath10k_htt *htt,
int fw_desc_len;
u8 *fw_desc;
int i, j;
- int ret;
- int ip_summed;
memset(&info, 0, sizeof(info));
@@ -930,11 +908,6 @@ static void ath10k_htt_rx_handler(struct ath10k_htt *htt,
continue;
}
- /* The skb is not yet processed and it may be
- * reallocated. Since the offload is in the original
- * skb extract the checksum now and assign it later */
- ip_summed = ath10k_htt_rx_get_csum_state(msdu_head);
-
info.skb = msdu_head;
info.fcs_err = ath10k_htt_rx_has_fcs_err(msdu_head);
info.signal = ATH10K_DEFAULT_NOISE_FLOOR;
@@ -947,24 +920,9 @@ static void ath10k_htt_rx_handler(struct ath10k_htt *htt,
hdr = ath10k_htt_rx_skb_get_hdr(msdu_head);
if (ath10k_htt_rx_hdr_is_amsdu(hdr))
- ret = ath10k_htt_rx_amsdu(htt, &info);
+ ath10k_htt_rx_amsdu(htt, &info);
else
- ret = ath10k_htt_rx_msdu(htt, &info);
-
- if (ret && !info.fcs_err) {
- ath10k_warn("error processing msdus %d\n", ret);
- dev_kfree_skb_any(info.skb);
- continue;
- }
-
- if (ath10k_htt_rx_hdr_is_amsdu((void *)info.skb->data))
- ath10k_dbg(ATH10K_DBG_HTT, "htt mpdu is amsdu\n");
-
- info.skb->ip_summed = ip_summed;
-
- ath10k_dbg_dump(ATH10K_DBG_HTT_DUMP, NULL, "htt mpdu: ",
- info.skb->data, info.skb->len);
- ath10k_process_rx(htt->ar, &info);
+ ath10k_htt_rx_msdu(htt, &info);
}
}
diff --git a/drivers/net/wireless/ath/ath10k/txrx.c b/drivers/net/wireless/ath/ath10k/txrx.c
index 57931d0..5ae373a 100644
--- a/drivers/net/wireless/ath/ath10k/txrx.c
+++ b/drivers/net/wireless/ath/ath10k/txrx.c
@@ -268,6 +268,8 @@ void ath10k_process_rx(struct ath10k *ar, struct htt_rx_info *info)
status->vht_nss,
status->freq,
status->band);
+ ath10k_dbg_dump(ATH10K_DBG_HTT_DUMP, NULL, "rx skb: ",
+ info->skb->data, info->skb->len);
ieee80211_rx(ar->hw, info->skb);
}
--
1.7.9.5
--
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