mac80211: make software rate control optional
Some devices implement the entire rate control in
firmware in some way, like wl1271 or like iwlwifi
which does some things in software but not a lot.
Therefore generic software rate control is rather
useless for them and just adds avoidable overhead
to the transmit path.
It's fairly simple to let drivers indicate that
they do not need rate control, but they need to
fulfil a number of conditions that we encode in
WARN_ONs.
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/net/mac80211/debugfs.c b/net/mac80211/debugfs.c
index 82c8077..e4b5409 100644
--- a/net/mac80211/debugfs.c
+++ b/net/mac80211/debugfs.c
@@ -52,7 +52,7 @@
DEBUGFS_READONLY_FILE(wep_iv, 20, "%#08x",
local->wep_iv & 0xffffff);
DEBUGFS_READONLY_FILE(rate_ctrl_alg, 100, "%s",
- local->rate_ctrl ? local->rate_ctrl->ops->name : "<unset>");
+ local->rate_ctrl ? local->rate_ctrl->ops->name : "hw/driver");
static ssize_t tsf_read(struct file *file, char __user *user_buf,
size_t count, loff_t *ppos)
diff --git a/net/mac80211/rate.c b/net/mac80211/rate.c
index ccda745..b9007f8 100644
--- a/net/mac80211/rate.c
+++ b/net/mac80211/rate.c
@@ -284,9 +284,16 @@
struct rate_control_ref *ref, *old;
ASSERT_RTNL();
+
if (local->open_count)
return -EBUSY;
+ if (local->hw.flags & IEEE80211_HW_HAS_RATE_CONTROL) {
+ if (WARN_ON(!local->ops->set_rts_threshold))
+ return -EINVAL;
+ return 0;
+ }
+
ref = rate_control_alloc(name, local);
if (!ref) {
printk(KERN_WARNING "%s: Failed to select rate control "
@@ -305,7 +312,6 @@
"algorithm '%s'\n", wiphy_name(local->hw.wiphy),
ref->ops->name);
-
return 0;
}
@@ -314,6 +320,10 @@
struct rate_control_ref *ref;
ref = local->rate_ctrl;
+
+ if (!ref)
+ return;
+
local->rate_ctrl = NULL;
rate_control_put(ref);
}
diff --git a/net/mac80211/rate.h b/net/mac80211/rate.h
index 2ab5ad9..cb9bd1f 100644
--- a/net/mac80211/rate.h
+++ b/net/mac80211/rate.h
@@ -59,6 +59,9 @@
void *priv_sta = sta->rate_ctrl_priv;
struct ieee80211_supported_band *sband;
+ if (!ref)
+ return;
+
sband = local->hw.wiphy->bands[local->hw.conf.channel->band];
ref->ops->rate_init(ref->priv, sband, ista, priv_sta);
@@ -72,7 +75,7 @@
struct ieee80211_sta *ista = &sta->sta;
void *priv_sta = sta->rate_ctrl_priv;
- if (ref->ops->rate_update)
+ if (ref && ref->ops->rate_update)
ref->ops->rate_update(ref->priv, sband, ista,
priv_sta, changed);
}
@@ -97,7 +100,7 @@
{
#ifdef CONFIG_MAC80211_DEBUGFS
struct rate_control_ref *ref = sta->rate_ctrl;
- if (sta->debugfs.dir && ref->ops->add_sta_debugfs)
+ if (ref && sta->debugfs.dir && ref->ops->add_sta_debugfs)
ref->ops->add_sta_debugfs(ref->priv, sta->rate_ctrl_priv,
sta->debugfs.dir);
#endif
@@ -107,7 +110,7 @@
{
#ifdef CONFIG_MAC80211_DEBUGFS
struct rate_control_ref *ref = sta->rate_ctrl;
- if (ref->ops->remove_sta_debugfs)
+ if (ref && ref->ops->remove_sta_debugfs)
ref->ops->remove_sta_debugfs(ref->priv, sta->rate_ctrl_priv);
#endif
}
diff --git a/net/mac80211/sta_info.c b/net/mac80211/sta_info.c
index aa017a5..71f370d 100644
--- a/net/mac80211/sta_info.c
+++ b/net/mac80211/sta_info.c
@@ -148,8 +148,10 @@
static void __sta_info_free(struct ieee80211_local *local,
struct sta_info *sta)
{
- rate_control_free_sta(sta);
- rate_control_put(sta->rate_ctrl);
+ if (sta->rate_ctrl) {
+ rate_control_free_sta(sta);
+ rate_control_put(sta->rate_ctrl);
+ }
#ifdef CONFIG_MAC80211_VERBOSE_DEBUG
printk(KERN_DEBUG "%s: Destroyed STA %pM\n",
@@ -277,6 +279,23 @@
ieee80211_sta_ps_deliver_poll_response(sta);
}
+static int sta_prepare_rate_control(struct ieee80211_local *local,
+ struct sta_info *sta, gfp_t gfp)
+{
+ if (local->hw.flags & IEEE80211_HW_HAS_RATE_CONTROL)
+ return 0;
+
+ sta->rate_ctrl = rate_control_get(local->rate_ctrl);
+ sta->rate_ctrl_priv = rate_control_alloc_sta(sta->rate_ctrl,
+ &sta->sta, gfp);
+ if (!sta->rate_ctrl_priv) {
+ rate_control_put(sta->rate_ctrl);
+ return -ENOMEM;
+ }
+
+ return 0;
+}
+
struct sta_info *sta_info_alloc(struct ieee80211_sub_if_data *sdata,
u8 *addr, gfp_t gfp)
{
@@ -296,11 +315,7 @@
sta->local = local;
sta->sdata = sdata;
- sta->rate_ctrl = rate_control_get(local->rate_ctrl);
- sta->rate_ctrl_priv = rate_control_alloc_sta(sta->rate_ctrl,
- &sta->sta, gfp);
- if (!sta->rate_ctrl_priv) {
- rate_control_put(sta->rate_ctrl);
+ if (sta_prepare_rate_control(local, sta, gfp)) {
kfree(sta);
return NULL;
}
diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c
index 3466e1f..bd91643 100644
--- a/net/mac80211/tx.c
+++ b/net/mac80211/tx.c
@@ -1219,7 +1219,8 @@
CALL_TXH(ieee80211_tx_h_ps_buf);
CALL_TXH(ieee80211_tx_h_select_key);
CALL_TXH(ieee80211_tx_h_michael_mic_add);
- CALL_TXH(ieee80211_tx_h_rate_ctrl);
+ if (!(tx->local->hw.flags & IEEE80211_HW_HAS_RATE_CONTROL))
+ CALL_TXH(ieee80211_tx_h_rate_ctrl);
CALL_TXH(ieee80211_tx_h_misc);
CALL_TXH(ieee80211_tx_h_sequence);
CALL_TXH(ieee80211_tx_h_fragment);