mac80211: support use of NAPI for bottom-half processing
This patch implement basic infrastructure to support use of NAPI by
mac80211-based hardware drivers.
Because mac80211 devices can support multiple netdevs, a dummy netdev
is used for interfacing with the NAPI code in the core of the network
stack. That structure is hidden from the hardware drivers, but the
actual napi_struct is exposed in the ieee80211_hw structure so that the
poll routines in drivers can retrieve that structure. Hardware drivers
can also specify their own weight value for NAPI polling.
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/include/net/mac80211.h b/include/net/mac80211.h
index b0787a1..3f1e03b 100644
--- a/include/net/mac80211.h
+++ b/include/net/mac80211.h
@@ -1102,6 +1102,10 @@
*
* @max_rates: maximum number of alternate rate retry stages
* @max_rate_tries: maximum number of tries for each stage
+ *
+ * @napi_weight: weight used for NAPI polling. You must specify an
+ * appropriate value here if a napi_poll operation is provided
+ * by your driver.
*/
struct ieee80211_hw {
struct ieee80211_conf conf;
@@ -1113,6 +1117,7 @@
int channel_change_time;
int vif_data_size;
int sta_data_size;
+ int napi_weight;
u16 queues;
u16 max_listen_interval;
s8 max_signal;
@@ -1687,6 +1692,8 @@
* switch operation for CSAs received from the AP may implement this
* callback. They must then call ieee80211_chswitch_done() to indicate
* completion of the channel switch.
+ *
+ * @napi_poll: Poll Rx queue for incoming data frames.
*/
struct ieee80211_ops {
int (*tx)(struct ieee80211_hw *hw, struct sk_buff *skb);
@@ -1752,6 +1759,7 @@
void (*flush)(struct ieee80211_hw *hw, bool drop);
void (*channel_switch)(struct ieee80211_hw *hw,
struct ieee80211_channel_switch *ch_switch);
+ int (*napi_poll)(struct ieee80211_hw *hw, int budget);
};
/**
@@ -1897,6 +1905,22 @@
*/
void ieee80211_restart_hw(struct ieee80211_hw *hw);
+/** ieee80211_napi_schedule - schedule NAPI poll
+ *
+ * Use this function to schedule NAPI polling on a device.
+ *
+ * @hw: the hardware to start polling
+ */
+void ieee80211_napi_schedule(struct ieee80211_hw *hw);
+
+/** ieee80211_napi_complete - complete NAPI polling
+ *
+ * Use this function to finish NAPI polling on a device.
+ *
+ * @hw: the hardware to stop polling
+ */
+void ieee80211_napi_complete(struct ieee80211_hw *hw);
+
/**
* ieee80211_rx - receive frame
*
diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h
index 65e0ed6..79d5645 100644
--- a/net/mac80211/ieee80211_i.h
+++ b/net/mac80211/ieee80211_i.h
@@ -870,6 +870,11 @@
struct dentry *keys;
} debugfs;
#endif
+
+ /* dummy netdev for use w/ NAPI */
+ struct net_device napi_dev;
+
+ struct napi_struct napi;
};
static inline struct ieee80211_sub_if_data *
diff --git a/net/mac80211/iface.c b/net/mac80211/iface.c
index ebbe264..c1008a9 100644
--- a/net/mac80211/iface.c
+++ b/net/mac80211/iface.c
@@ -187,6 +187,8 @@
res = drv_start(local);
if (res)
goto err_del_bss;
+ if (local->ops->napi_poll)
+ napi_enable(&local->napi);
/* we're brought up, everything changes */
hw_reconf_flags = ~0;
ieee80211_led_radio(local, true);
@@ -519,6 +521,8 @@
ieee80211_recalc_ps(local, -1);
if (local->open_count == 0) {
+ if (local->ops->napi_poll)
+ napi_disable(&local->napi);
ieee80211_clear_tx_pending(local);
ieee80211_stop_device(local);
diff --git a/net/mac80211/main.c b/net/mac80211/main.c
index 798a91b..1ed956c 100644
--- a/net/mac80211/main.c
+++ b/net/mac80211/main.c
@@ -390,6 +390,30 @@
}
#endif
+static int ieee80211_napi_poll(struct napi_struct *napi, int budget)
+{
+ struct ieee80211_local *local =
+ container_of(napi, struct ieee80211_local, napi);
+
+ return local->ops->napi_poll(&local->hw, budget);
+}
+
+void ieee80211_napi_schedule(struct ieee80211_hw *hw)
+{
+ struct ieee80211_local *local = hw_to_local(hw);
+
+ napi_schedule(&local->napi);
+}
+EXPORT_SYMBOL(ieee80211_napi_schedule);
+
+void ieee80211_napi_complete(struct ieee80211_hw *hw)
+{
+ struct ieee80211_local *local = hw_to_local(hw);
+
+ napi_complete(&local->napi);
+}
+EXPORT_SYMBOL(ieee80211_napi_complete);
+
struct ieee80211_hw *ieee80211_alloc_hw(size_t priv_data_len,
const struct ieee80211_ops *ops)
{
@@ -494,6 +518,9 @@
skb_queue_head_init(&local->skb_queue);
skb_queue_head_init(&local->skb_queue_unreliable);
+ /* init dummy netdev for use w/ NAPI */
+ init_dummy_netdev(&local->napi_dev);
+
return local_to_hw(local);
}
EXPORT_SYMBOL(ieee80211_alloc_hw);
@@ -683,6 +710,9 @@
goto fail_ifa;
#endif
+ netif_napi_add(&local->napi_dev, &local->napi, ieee80211_napi_poll,
+ local->hw.napi_weight);
+
return 0;
#ifdef CONFIG_INET