From c5d1686b314ea44c5f210990dee05caf98cb068f Mon Sep 17 00:00:00 2001
From: Felix Fietkau <nbd@nbd.name>
Date: Sun, 26 Jul 2020 13:06:11 +0200
Subject: [PATCH] mac80211: add a function for running rx without passing skbs to the stack
Git-commit: c5d1686b314ea44c5f210990dee05caf98cb068f
Patch-mainline: v5.9-rc1
References: jsc#SLE-13430
This can be used to run mac80211 rx processing on a batch of frames in NAPI
poll before passing them to the network stack in a large batch.
This can improve icache footprint, or it can be used to pass frames via
netif_receive_skb_list.
Signed-off-by: Felix Fietkau <nbd@nbd.name>
Link: https://lore.kernel.org/r/20200726110611.46886-1-nbd@nbd.name
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Acked-by: Takashi Iwai <tiwai@suse.de>
---
include/net/mac80211.h | 25 +++++++++++++++++++
net/mac80211/ieee80211_i.h | 2 +-
net/mac80211/rx.c | 60 +++++++++++++++++++++++++++++-----------------
3 files changed, 64 insertions(+), 23 deletions(-)
diff --git a/include/net/mac80211.h b/include/net/mac80211.h
index 6e26f0ba6fd0..66e2bfd165e8 100644
--- a/include/net/mac80211.h
+++ b/include/net/mac80211.h
@@ -4360,6 +4360,31 @@ void ieee80211_free_hw(struct ieee80211_hw *hw);
*/
void ieee80211_restart_hw(struct ieee80211_hw *hw);
+/**
+ * ieee80211_rx_list - receive frame and store processed skbs in a list
+ *
+ * Use this function to hand received frames to mac80211. The receive
+ * buffer in @skb must start with an IEEE 802.11 header. In case of a
+ * paged @skb is used, the driver is recommended to put the ieee80211
+ * header of the frame on the linear part of the @skb to avoid memory
+ * allocation and/or memcpy by the stack.
+ *
+ * This function may not be called in IRQ context. Calls to this function
+ * for a single hardware must be synchronized against each other. Calls to
+ * this function, ieee80211_rx_ni() and ieee80211_rx_irqsafe() may not be
+ * mixed for a single hardware. Must not run concurrently with
+ * ieee80211_tx_status() or ieee80211_tx_status_ni().
+ *
+ * This function must be called with BHs disabled and RCU read lock
+ *
+ * @hw: the hardware this frame came in on
+ * @sta: the station the frame was received from, or %NULL
+ * @skb: the buffer to receive, owned by mac80211 after this call
+ * @list: the destination list
+ */
+void ieee80211_rx_list(struct ieee80211_hw *hw, struct ieee80211_sta *sta,
+ struct sk_buff *skb, struct list_head *list);
+
/**
* ieee80211_rx_napi - receive frame from NAPI context
*
diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h
index 1760ce77d89f..0b1eaec6649f 100644
--- a/net/mac80211/ieee80211_i.h
+++ b/net/mac80211/ieee80211_i.h
@@ -217,7 +217,7 @@ enum ieee80211_rx_flags {
};
struct ieee80211_rx_data {
- struct napi_struct *napi;
+ struct list_head *list;
struct sk_buff *skb;
struct ieee80211_local *local;
struct ieee80211_sub_if_data *sdata;
diff --git a/net/mac80211/rx.c b/net/mac80211/rx.c
index 9ac3eaa00ce6..836cde516a18 100644
--- a/net/mac80211/rx.c
+++ b/net/mac80211/rx.c
@@ -2578,8 +2578,8 @@ static void ieee80211_deliver_skb_to_local_stack(struct sk_buff *skb,
memset(skb->cb, 0, sizeof(skb->cb));
/* deliver to local stack */
- if (rx->napi)
- napi_gro_receive(rx->napi, skb);
+ if (rx->list)
+ list_add_tail(&skb->list, rx->list);
else
netif_receive_skb(skb);
}
@@ -3869,7 +3869,6 @@ void ieee80211_release_reorder_timeout(struct sta_info *sta, int tid)
/* This is OK -- must be QoS data frame */
.security_idx = tid,
.seqno_idx = tid,
- .napi = NULL, /* must be NULL to not have races */
};
struct tid_ampdu_rx *tid_agg_rx;
@@ -4479,8 +4478,8 @@ static bool ieee80211_invoke_fast_rx(struct ieee80211_rx_data *rx,
/* deliver to local stack */
skb->protocol = eth_type_trans(skb, fast_rx->dev);
memset(skb->cb, 0, sizeof(skb->cb));
- if (rx->napi)
- napi_gro_receive(rx->napi, skb);
+ if (rx->list)
+ list_add_tail(&skb->list, rx->list);
else
netif_receive_skb(skb);
@@ -4547,7 +4546,7 @@ static bool ieee80211_prepare_and_rx_handle(struct ieee80211_rx_data *rx,
static void __ieee80211_rx_handle_packet(struct ieee80211_hw *hw,
struct ieee80211_sta *pubsta,
struct sk_buff *skb,
- struct napi_struct *napi)
+ struct list_head *list)
{
struct ieee80211_local *local = hw_to_local(hw);
struct ieee80211_sub_if_data *sdata;
@@ -4562,7 +4561,7 @@ static void __ieee80211_rx_handle_packet(struct ieee80211_hw *hw,
memset(&rx, 0, sizeof(rx));
rx.skb = skb;
rx.local = local;
- rx.napi = napi;
+ rx.list = list;
if (ieee80211_is_data(fc) || ieee80211_is_mgmt(fc))
I802_DEBUG_INC(local->dot11ReceivedFragmentCount);
@@ -4670,8 +4669,8 @@ static void __ieee80211_rx_handle_packet(struct ieee80211_hw *hw,
* This is the receive path handler. It is called by a low level driver when an
* 802.11 MPDU is received from the hardware.
*/
-void ieee80211_rx_napi(struct ieee80211_hw *hw, struct ieee80211_sta *pubsta,
- struct sk_buff *skb, struct napi_struct *napi)
+void ieee80211_rx_list(struct ieee80211_hw *hw, struct ieee80211_sta *pubsta,
+ struct sk_buff *skb, struct list_head *list)
{
struct ieee80211_local *local = hw_to_local(hw);
struct ieee80211_rate *rate = NULL;
@@ -4762,13 +4761,6 @@ void ieee80211_rx_napi(struct ieee80211_hw *hw, struct ieee80211_sta *pubsta,
status->rx_flags = 0;
- /*
- * key references and virtual interfaces are protected using RCU
- * and this requires that we are in a read-side RCU section during
- * receive processing
- */
- rcu_read_lock();
-
/*
* Frames with failed FCS/PLCP checksum are not returned,
* all other frames are returned without radiotap header
@@ -4776,23 +4768,47 @@ void ieee80211_rx_napi(struct ieee80211_hw *hw, struct ieee80211_sta *pubsta,
* Also, frames with less than 16 bytes are dropped.
*/
skb = ieee80211_rx_monitor(local, skb, rate);
- if (!skb) {
- rcu_read_unlock();
+ if (!skb)
return;
- }
ieee80211_tpt_led_trig_rx(local,
((struct ieee80211_hdr *)skb->data)->frame_control,
skb->len);
- __ieee80211_rx_handle_packet(hw, pubsta, skb, napi);
-
- rcu_read_unlock();
+ __ieee80211_rx_handle_packet(hw, pubsta, skb, list);
return;
drop:
kfree_skb(skb);
}
+EXPORT_SYMBOL(ieee80211_rx_list);
+
+void ieee80211_rx_napi(struct ieee80211_hw *hw, struct ieee80211_sta *pubsta,
+ struct sk_buff *skb, struct napi_struct *napi)
+{
+ struct sk_buff *tmp;
+ LIST_HEAD(list);
+
+
+ /*
+ * key references and virtual interfaces are protected using RCU
+ * and this requires that we are in a read-side RCU section during
+ * receive processing
+ */
+ rcu_read_lock();
+ ieee80211_rx_list(hw, pubsta, skb, &list);
+ rcu_read_unlock();
+
+ if (!napi) {
+ netif_receive_skb_list(&list);
+ return;
+ }
+
+ list_for_each_entry_safe(skb, tmp, &list, list) {
+ skb_list_del_init(skb);
+ napi_gro_receive(napi, skb);
+ }
+}
EXPORT_SYMBOL(ieee80211_rx_napi);
/* This is a version of the rx handler that can be called from hard irq
--
2.16.4