In case of A-MSDU RX we should check attention flags
correctly to be sure we report correct FCS status for
A-MSDU subframes. Without a patch we could report A-MSDU
subframes with wrong FCS as a correct to the stack, next
get a lot of DUP ACK TCP packets. Finally TP drop is seen
and this drop depends on FCS errors ratio for A-MSDU frame.
Example test case when TP drop is seen:
- ath10k configured as an AP
- used ath10k station
- forced A-MSDU (7 frames) on STA
- other traffic on channel (often FCS errors)
- monitor iface added on AP
- TCP STA -> AP traffic (iperf)
a) Iperf logs for case without the patch:
echo "1 64" > htt_max_amsdu_ampdu // disable A-MSDU
[ ID] Interval Transfer Bandwidth
[ 3] 0.0- 5.0 sec 56.6 MBytes 95.0 Mbits/sec
[ 3] 5.0-10.0 sec 60.4 MBytes 101 Mbits/sec
[ 3] 10.0-15.0 sec 60.2 MBytes 101 Mbits/sec
[ 3] 15.0-20.0 sec 60.2 MBytes 101 Mbits/sec
[ 3] 20.0-25.0 sec 63.8 MBytes 107 Mbits/sec
[ 3] 25.0-30.0 sec 64.9 MBytes 109 Mbits/sec
echo "7 64" > htt_max_amsdu_ampdu // set 7 A-MSDU subframes
[ 3] 30.0-35.0 sec 40.0 MBytes 67.1 Mbits/sec
[ 3] 35.0-40.0 sec 35.9 MBytes 60.2 Mbits/sec
[ 3] 40.0-45.0 sec 36.9 MBytes 61.9 Mbits/sec
[ 3] 45.0-50.0 sec 37.9 MBytes 63.5 Mbits/sec
[ 3] 50.0-55.0 sec 34.5 MBytes 57.9 Mbits/sec
[ 3] 55.0-60.0 sec 25.4 MBytes 42.6 Mbits/sec
[ 3] 60.0-65.0 sec 48.2 MBytes 81.0 Mbits/sec
[ 3] 65.0-70.0 sec 28.8 MBytes 48.2 Mbits/sec
[ 3] 70.0-75.0 sec 29.2 MBytes 49.1 Mbits/sec
[ 3] 75.0-80.0 sec 22.9 MBytes 38.4 Mbits/sec
[ 3] 80.0-85.0 sec 26.4 MBytes 44.2 Mbits/sec
[ 3] 85.0-90.0 sec 31.5 MBytes 52.8 Mbits/sec
b) Iperf logs for case with patch:
echo "1 64" > htt_max_amsdu_ampdu // disable A-MSDU
[ 3] local 192.168.12.2 port 57512 connected with 192.168.12.1 port 5001
[ ID] Interval Transfer Bandwidth
[ 3] 0.0- 5.0 sec 60.8 MBytes 102 Mbits/sec
[ 3] 5.0-10.0 sec 62.2 MBytes 104 Mbits/sec
[ 3] 10.0-15.0 sec 60.9 MBytes 102 Mbits/sec
echo "7 64" > htt_max_amsdu_ampdu // set 7 A-MSDU subframes
[ 3] 15.0-20.0 sec 68.1 MBytes 114 Mbits/sec
[ 3] 20.0-25.0 sec 80.5 MBytes 135 Mbits/sec
[ 3] 25.0-30.0 sec 83.0 MBytes 139 Mbits/sec
[ 3] 30.0-35.0 sec 79.1 MBytes 133 Mbits/sec
[ 3] 35.0-40.0 sec 77.1 MBytes 129 Mbits/sec
[ 3] 40.0-45.0 sec 77.4 MBytes 130 Mbits/sec
Reported-by: Denton Gentry <denton.gentry@xxxxxxxxx>
Signed-off-by: Janusz Dziedzic <janusz.dziedzic@xxxxxxxxx>
---
*v2 - changed commit message
drivers/net/wireless/ath/ath10k/htt_rx.c | 23 +++++++++++++++--------
1 file changed, 15 insertions(+), 8 deletions(-)
diff --git a/drivers/net/wireless/ath/ath10k/htt_rx.c b/drivers/net/wireless/ath/ath10k/htt_rx.c
index 8e14c58..4767d22 100644
--- a/drivers/net/wireless/ath/ath10k/htt_rx.c
+++ b/drivers/net/wireless/ath/ath10k/htt_rx.c
@@ -307,7 +307,8 @@ static void ath10k_htt_rx_free_msdu_chain(struct sk_buff *skb)
static int ath10k_htt_rx_amsdu_pop(struct ath10k_htt *htt,
u8 **fw_desc, int *fw_desc_len,
struct sk_buff **head_msdu,
- struct sk_buff **tail_msdu)
+ struct sk_buff **tail_msdu,
+ u32 *attention)
{
int msdu_len, msdu_chaining = 0;
struct sk_buff *msdu;
@@ -357,6 +358,11 @@ static int ath10k_htt_rx_amsdu_pop(struct ath10k_htt *htt,
break;
}
+ *attention |= __le32_to_cpu(rx_desc->attention.flags) &
+ (RX_ATTENTION_FLAGS_TKIP_MIC_ERR |
+ RX_ATTENTION_FLAGS_DECRYPT_ERR |
+ RX_ATTENTION_FLAGS_FCS_ERR |
+ RX_ATTENTION_FLAGS_MGMT_TYPE);
/*
* Copy the FW rx descriptor for this MSDU from the rx
* indication message into the MSDU's netbuf. HL uses the
@@ -1256,13 +1262,15 @@ static void ath10k_htt_rx_handler(struct ath10k_htt *htt,
for (j = 0; j < mpdu_ranges[i].mpdu_count; j++) {
struct sk_buff *msdu_head, *msdu_tail;
+ attention = 0;
msdu_head = NULL;
msdu_tail = NULL;
ret = ath10k_htt_rx_amsdu_pop(htt,
&fw_desc,
&fw_desc_len,
&msdu_head,
- &msdu_tail);
+ &msdu_tail,
+ &attention);
if (ret < 0) {
ath10k_warn("failed to pop amsdu from htt rx ring %d\n",
@@ -1274,7 +1282,6 @@ static void ath10k_htt_rx_handler(struct ath10k_htt *htt,
rxd = container_of((void *)msdu_head->data,
struct htt_rx_desc,
msdu_payload);
- attention = __le32_to_cpu(rxd->attention.flags);
if (!ath10k_htt_rx_amsdu_allowed(htt, msdu_head,
status,
@@ -1327,6 +1334,7 @@ static void ath10k_htt_rx_frag_handler(struct ath10k_htt *htt,
u8 *fw_desc;
int fw_desc_len, hdrlen, paramlen;
int trim;
+ u32 attention = 0;
fw_desc_len = __le16_to_cpu(frag->fw_rx_desc_bytes);
fw_desc = (u8 *)frag->fw_msdu_rx_desc;
@@ -1336,7 +1344,8 @@ static void ath10k_htt_rx_frag_handler(struct ath10k_htt *htt,
spin_lock_bh(&htt->rx_ring.lock);
ret = ath10k_htt_rx_amsdu_pop(htt, &fw_desc, &fw_desc_len,
- &msdu_head, &msdu_tail);
+ &msdu_head, &msdu_tail,
+ &attention);
spin_unlock_bh(&htt->rx_ring.lock);
ath10k_dbg(ATH10K_DBG_HTT_DUMP, "htt rx frag ahead\n");
@@ -1353,10 +1362,8 @@ static void ath10k_htt_rx_frag_handler(struct ath10k_htt *htt,
hdr = (struct ieee80211_hdr *)msdu_head->data;
rxd = (void *)msdu_head->data - sizeof(*rxd);
- tkip_mic_err = !!(__le32_to_cpu(rxd->attention.flags) &
- RX_ATTENTION_FLAGS_TKIP_MIC_ERR);
- decrypt_err = !!(__le32_to_cpu(rxd->attention.flags) &
- RX_ATTENTION_FLAGS_DECRYPT_ERR);
+ tkip_mic_err = !!(attention & RX_ATTENTION_FLAGS_TKIP_MIC_ERR);
+ decrypt_err = !!(attention & RX_ATTENTION_FLAGS_DECRYPT_ERR);
fmt = MS(__le32_to_cpu(rxd->msdu_start.info1),
RX_MSDU_START_INFO1_DECAP_FORMAT);
--
1.7.9.5
--
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
