mirror of
https://github.com/openwrt/openwrt.git
synced 2024-12-28 01:28:59 +00:00
ac7ccf739a
This updates to backports-4.19.57-1 which contains the wireless subsystem and driver from kernel 4.19.57. The removed patches are applied upstream. Tested-by: Koen Vandeputte <koen.vandeputte@ncentric.com> Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>
203 lines
7.0 KiB
Diff
203 lines
7.0 KiB
Diff
From: Felix Fietkau <nbd@nbd.name>
|
|
Date: Sun, 17 Mar 2019 18:11:30 +0100
|
|
Subject: [PATCH] mac80211: optimize skb resizing
|
|
|
|
When forwarding unicast packets from ethernet to batman-adv over 802.11s
|
|
(with forwarding disabled), the typical required headroom to transmit
|
|
encrypted packets on mt76 is 32 (802.11) + 6 (802.11s) + 8 (CCMP) +
|
|
2 (padding) + 6 (LLC) + 18 (batman-adv) - 14 (old ethernet header) = 58 bytes.
|
|
|
|
On systems where NET_SKB_PAD is 64 this leads to a call to pskb_expand_head
|
|
for every packet, since mac80211 also tries to allocate 16 bytes status
|
|
headroom for radiotap headers.
|
|
|
|
This patch fixes these unnecessary reallocations by only requiring the extra
|
|
status headroom in ieee80211_tx_monitor()
|
|
If however a reallocation happens before that call, the status headroom gets
|
|
added there as well, in order to avoid double reallocation.
|
|
|
|
The patch also cleans up the code by moving the headroom calculation to
|
|
ieee80211_skb_resize.
|
|
|
|
Signed-off-by: Felix Fietkau <nbd@nbd.name>
|
|
---
|
|
|
|
--- a/net/mac80211/ieee80211_i.h
|
|
+++ b/net/mac80211/ieee80211_i.h
|
|
@@ -1761,6 +1761,9 @@ void ieee80211_clear_fast_xmit(struct st
|
|
int ieee80211_tx_control_port(struct wiphy *wiphy, struct net_device *dev,
|
|
const u8 *buf, size_t len,
|
|
const u8 *dest, __be16 proto, bool unencrypted);
|
|
+int ieee80211_skb_resize(struct ieee80211_local *local,
|
|
+ struct ieee80211_sub_if_data *sdata,
|
|
+ struct sk_buff *skb, int hdrlen, int hdr_add);
|
|
|
|
/* HT */
|
|
void ieee80211_apply_htcap_overrides(struct ieee80211_sub_if_data *sdata,
|
|
--- a/net/mac80211/status.c
|
|
+++ b/net/mac80211/status.c
|
|
@@ -672,6 +672,11 @@ void ieee80211_tx_monitor(struct ieee802
|
|
}
|
|
}
|
|
|
|
+ if (ieee80211_skb_resize(local, NULL, skb, 0, 0)) {
|
|
+ dev_kfree_skb(skb);
|
|
+ return;
|
|
+ }
|
|
+
|
|
/* send frame to monitor interfaces now */
|
|
rtap_len = ieee80211_tx_radiotap_len(info);
|
|
if (WARN_ON_ONCE(skb_headroom(skb) < rtap_len)) {
|
|
--- a/net/mac80211/tx.c
|
|
+++ b/net/mac80211/tx.c
|
|
@@ -1914,37 +1914,53 @@ static bool ieee80211_tx(struct ieee8021
|
|
}
|
|
|
|
/* device xmit handlers */
|
|
-
|
|
-static int ieee80211_skb_resize(struct ieee80211_sub_if_data *sdata,
|
|
- struct sk_buff *skb,
|
|
- int head_need, bool may_encrypt)
|
|
+int ieee80211_skb_resize(struct ieee80211_local *local,
|
|
+ struct ieee80211_sub_if_data *sdata,
|
|
+ struct sk_buff *skb, int hdr_len, int hdr_extra)
|
|
{
|
|
- struct ieee80211_local *local = sdata->local;
|
|
+ struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
|
|
struct ieee80211_hdr *hdr;
|
|
- bool enc_tailroom;
|
|
- int tail_need = 0;
|
|
-
|
|
- hdr = (struct ieee80211_hdr *) skb->data;
|
|
- enc_tailroom = may_encrypt &&
|
|
- (sdata->crypto_tx_tailroom_needed_cnt ||
|
|
- ieee80211_is_mgmt(hdr->frame_control));
|
|
-
|
|
- if (enc_tailroom) {
|
|
- tail_need = IEEE80211_ENCRYPT_TAILROOM;
|
|
- tail_need -= skb_tailroom(skb);
|
|
- tail_need = max_t(int, tail_need, 0);
|
|
+ int head_need, head_max;
|
|
+ int tail_need, tail_max;
|
|
+ bool enc_tailroom = false;
|
|
+
|
|
+ if (sdata && !hdr_len &&
|
|
+ !(info->flags & IEEE80211_TX_INTFL_DONT_ENCRYPT)) {
|
|
+ hdr = (struct ieee80211_hdr *) skb->data;
|
|
+ enc_tailroom = (sdata->crypto_tx_tailroom_needed_cnt ||
|
|
+ ieee80211_is_mgmt(hdr->frame_control));
|
|
+ hdr_len += sdata->encrypt_headroom;
|
|
+ }
|
|
+
|
|
+ head_need = head_max = hdr_len;
|
|
+ tail_need = tail_max = 0;
|
|
+ if (!sdata) {
|
|
+ head_need = head_max = local->tx_headroom;
|
|
+ } else {
|
|
+ head_max += hdr_extra;
|
|
+ head_max += max_t(int, local->tx_headroom,
|
|
+ local->hw.extra_tx_headroom);
|
|
+ head_need += local->hw.extra_tx_headroom;
|
|
+
|
|
+ tail_max = IEEE80211_ENCRYPT_TAILROOM;
|
|
+ if (enc_tailroom)
|
|
+ tail_need = tail_max;
|
|
}
|
|
|
|
if (skb_cloned(skb) &&
|
|
(!ieee80211_hw_check(&local->hw, SUPPORTS_CLONED_SKBS) ||
|
|
!skb_clone_writable(skb, ETH_HLEN) || enc_tailroom))
|
|
I802_DEBUG_INC(local->tx_expand_skb_head_cloned);
|
|
- else if (head_need || tail_need)
|
|
+ else if (head_need > skb_headroom(skb) ||
|
|
+ tail_need > skb_tailroom(skb))
|
|
I802_DEBUG_INC(local->tx_expand_skb_head);
|
|
else
|
|
return 0;
|
|
|
|
- if (pskb_expand_head(skb, head_need, tail_need, GFP_ATOMIC)) {
|
|
+ head_max = max_t(int, 0, head_max - skb_headroom(skb));
|
|
+ tail_max = max_t(int, 0, tail_max - skb_tailroom(skb));
|
|
+
|
|
+ if (pskb_expand_head(skb, head_max, tail_max, GFP_ATOMIC)) {
|
|
wiphy_debug(local->hw.wiphy,
|
|
"failed to reallocate TX buffer\n");
|
|
return -ENOMEM;
|
|
@@ -1960,18 +1976,8 @@ void ieee80211_xmit(struct ieee80211_sub
|
|
struct ieee80211_local *local = sdata->local;
|
|
struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
|
|
struct ieee80211_hdr *hdr;
|
|
- int headroom;
|
|
- bool may_encrypt;
|
|
-
|
|
- may_encrypt = !(info->flags & IEEE80211_TX_INTFL_DONT_ENCRYPT);
|
|
|
|
- headroom = local->tx_headroom;
|
|
- if (may_encrypt)
|
|
- headroom += sdata->encrypt_headroom;
|
|
- headroom -= skb_headroom(skb);
|
|
- headroom = max_t(int, 0, headroom);
|
|
-
|
|
- if (ieee80211_skb_resize(sdata, skb, headroom, may_encrypt)) {
|
|
+ if (ieee80211_skb_resize(local, sdata, skb, 0, 0)) {
|
|
ieee80211_free_txskb(&local->hw, skb);
|
|
return;
|
|
}
|
|
@@ -2740,30 +2746,14 @@ static struct sk_buff *ieee80211_build_h
|
|
|
|
skb_pull(skb, skip_header_bytes);
|
|
padsize = ieee80211_hdr_padsize(&local->hw, hdrlen);
|
|
- head_need = hdrlen + encaps_len + meshhdrlen - skb_headroom(skb);
|
|
+ head_need = hdrlen + encaps_len + meshhdrlen;
|
|
head_need += padsize;
|
|
|
|
- /*
|
|
- * So we need to modify the skb header and hence need a copy of
|
|
- * that. The head_need variable above doesn't, so far, include
|
|
- * the needed header space that we don't need right away. If we
|
|
- * can, then we don't reallocate right now but only after the
|
|
- * frame arrives at the master device (if it does...)
|
|
- *
|
|
- * If we cannot, however, then we will reallocate to include all
|
|
- * the ever needed space. Also, if we need to reallocate it anyway,
|
|
- * make it big enough for everything we may ever need.
|
|
- */
|
|
-
|
|
- if (head_need > 0 || skb_cloned(skb)) {
|
|
- head_need += sdata->encrypt_headroom;
|
|
- head_need += local->tx_headroom;
|
|
- head_need = max_t(int, 0, head_need);
|
|
- if (ieee80211_skb_resize(sdata, skb, head_need, true)) {
|
|
- ieee80211_free_txskb(&local->hw, skb);
|
|
- skb = NULL;
|
|
- return ERR_PTR(-ENOMEM);
|
|
- }
|
|
+ if (ieee80211_skb_resize(local, sdata, skb, head_need,
|
|
+ sdata->encrypt_headroom)) {
|
|
+ ieee80211_free_txskb(&local->hw, skb);
|
|
+ skb = NULL;
|
|
+ return ERR_PTR(-ENOMEM);
|
|
}
|
|
|
|
if (encaps_data)
|
|
@@ -3375,7 +3365,6 @@ static bool ieee80211_xmit_fast(struct i
|
|
struct ieee80211_local *local = sdata->local;
|
|
u16 ethertype = (skb->data[12] << 8) | skb->data[13];
|
|
int extra_head = fast_tx->hdr_len - (ETH_HLEN - 2);
|
|
- int hw_headroom = sdata->local->hw.extra_tx_headroom;
|
|
struct ethhdr eth;
|
|
struct ieee80211_tx_info *info;
|
|
struct ieee80211_hdr *hdr = (void *)fast_tx->hdr;
|
|
@@ -3427,10 +3416,7 @@ static bool ieee80211_xmit_fast(struct i
|
|
* as the may-encrypt argument for the resize to not account for
|
|
* more room than we already have in 'extra_head'
|
|
*/
|
|
- if (unlikely(ieee80211_skb_resize(sdata, skb,
|
|
- max_t(int, extra_head + hw_headroom -
|
|
- skb_headroom(skb), 0),
|
|
- false))) {
|
|
+ if (unlikely(ieee80211_skb_resize(local, sdata, skb, extra_head, 0))) {
|
|
kfree_skb(skb);
|
|
return true;
|
|
}
|