mac80211: Optimize scans on current operating channel.

This should decrease un-necessary flushes, on/off channel work,
and channel changes in cases where the only scanned channel is
the current operating channel.

* Removes SCAN_OFF_CHANNEL flag, uses SDATA_STATE_OFFCHANNEL
  and is-scanning flags instead.

* Add helper method to determine if we are currently configured
  for the operating channel.

* Do no blindly go off/on channel in work.c  Instead, only call
  appropriate on/off code when we really need to change channels.
  Always enable offchannel-ps mode when starting work,
  and disable it when we are done.

* Consolidate ieee80211_offchannel_stop_station and
  ieee80211_offchannel_stop_beaconing, call it
  ieee80211_offchannel_stop_vifs instead.

* Accept non-beacon frames when scanning on operating channel.

* Scan state machine optimized to minimize on/off channel
  transitions.  Also, when going on-channel, go ahead and
  re-enable beaconing.  We're going to be there for 200ms,
  so seems like some useful beaconing could happen.
  Always enable offchannel-ps mode when starting software
  scan, and disable it when we are done.

* Grab local->mtx earlier in __ieee80211_scan_completed_finish
  so that we are protected when calling hw_config(), etc.

* Pass probe-responses up the stack if scanning on local
  channel, so that mlme can take a look.

Signed-off-by: Ben Greear <greearb@candelatech.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
This commit is contained in:
Ben Greear
2011-02-04 11:54:17 -08:00
committed by John W. Linville
parent cb8d61de2d
commit b23b025fe2
7 changed files with 233 additions and 108 deletions

View File

@@ -17,10 +17,14 @@
#include "driver-trace.h"
/*
* inform AP that we will go to sleep so that it will buffer the frames
* while we scan
* Tell our hardware to disable PS.
* Optionally inform AP that we will go to sleep so that it will buffer
* the frames while we are doing off-channel work. This is optional
* because we *may* be doing work on-operating channel, and want our
* hardware unconditionally awake, but still let the AP send us normal frames.
*/
static void ieee80211_offchannel_ps_enable(struct ieee80211_sub_if_data *sdata)
static void ieee80211_offchannel_ps_enable(struct ieee80211_sub_if_data *sdata,
bool tell_ap)
{
struct ieee80211_local *local = sdata->local;
struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
@@ -41,8 +45,8 @@ static void ieee80211_offchannel_ps_enable(struct ieee80211_sub_if_data *sdata)
ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_PS);
}
if (!(local->offchannel_ps_enabled) ||
!(local->hw.flags & IEEE80211_HW_PS_NULLFUNC_STACK))
if (tell_ap && (!local->offchannel_ps_enabled ||
!(local->hw.flags & IEEE80211_HW_PS_NULLFUNC_STACK)))
/*
* If power save was enabled, no need to send a nullfunc
* frame because AP knows that we are sleeping. But if the
@@ -77,6 +81,9 @@ static void ieee80211_offchannel_ps_disable(struct ieee80211_sub_if_data *sdata)
* we are sleeping, let's just enable power save mode in
* hardware.
*/
/* TODO: Only set hardware if CONF_PS changed?
* TODO: Should we set offchannel_ps_enabled to false?
*/
local->hw.conf.flags |= IEEE80211_CONF_PS;
ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_PS);
} else if (local->hw.conf.dynamic_ps_timeout > 0) {
@@ -95,63 +102,61 @@ static void ieee80211_offchannel_ps_disable(struct ieee80211_sub_if_data *sdata)
ieee80211_sta_reset_conn_monitor(sdata);
}
void ieee80211_offchannel_stop_beaconing(struct ieee80211_local *local)
{
struct ieee80211_sub_if_data *sdata;
mutex_lock(&local->iflist_mtx);
list_for_each_entry(sdata, &local->interfaces, list) {
if (!ieee80211_sdata_running(sdata))
continue;
/* disable beaconing */
if (sdata->vif.type == NL80211_IFTYPE_AP ||
sdata->vif.type == NL80211_IFTYPE_ADHOC ||
sdata->vif.type == NL80211_IFTYPE_MESH_POINT)
ieee80211_bss_info_change_notify(
sdata, BSS_CHANGED_BEACON_ENABLED);
/*
* only handle non-STA interfaces here, STA interfaces
* are handled in ieee80211_offchannel_stop_station(),
* e.g., from the background scan state machine.
*
* In addition, do not stop monitor interface to allow it to be
* used from user space controlled off-channel operations.
*/
if (sdata->vif.type != NL80211_IFTYPE_STATION &&
sdata->vif.type != NL80211_IFTYPE_MONITOR) {
set_bit(SDATA_STATE_OFFCHANNEL, &sdata->state);
netif_tx_stop_all_queues(sdata->dev);
}
}
mutex_unlock(&local->iflist_mtx);
}
void ieee80211_offchannel_stop_station(struct ieee80211_local *local)
void ieee80211_offchannel_stop_vifs(struct ieee80211_local *local,
bool offchannel_ps_enable)
{
struct ieee80211_sub_if_data *sdata;
/*
* notify the AP about us leaving the channel and stop all STA interfaces
* notify the AP about us leaving the channel and stop all
* STA interfaces.
*/
mutex_lock(&local->iflist_mtx);
list_for_each_entry(sdata, &local->interfaces, list) {
if (!ieee80211_sdata_running(sdata))
continue;
if (sdata->vif.type == NL80211_IFTYPE_STATION) {
if (sdata->vif.type != NL80211_IFTYPE_MONITOR)
set_bit(SDATA_STATE_OFFCHANNEL, &sdata->state);
/* Check to see if we should disable beaconing. */
if (sdata->vif.type == NL80211_IFTYPE_AP ||
sdata->vif.type == NL80211_IFTYPE_ADHOC ||
sdata->vif.type == NL80211_IFTYPE_MESH_POINT)
ieee80211_bss_info_change_notify(
sdata, BSS_CHANGED_BEACON_ENABLED);
if (sdata->vif.type != NL80211_IFTYPE_MONITOR) {
netif_tx_stop_all_queues(sdata->dev);
if (sdata->u.mgd.associated)
ieee80211_offchannel_ps_enable(sdata);
if (offchannel_ps_enable &&
(sdata->vif.type == NL80211_IFTYPE_STATION) &&
sdata->u.mgd.associated)
ieee80211_offchannel_ps_enable(sdata, true);
}
}
mutex_unlock(&local->iflist_mtx);
}
void ieee80211_offchannel_enable_all_ps(struct ieee80211_local *local,
bool tell_ap)
{
struct ieee80211_sub_if_data *sdata;
mutex_lock(&local->iflist_mtx);
list_for_each_entry(sdata, &local->interfaces, list) {
if (!ieee80211_sdata_running(sdata))
continue;
if (sdata->vif.type == NL80211_IFTYPE_STATION &&
sdata->u.mgd.associated)
ieee80211_offchannel_ps_enable(sdata, tell_ap);
}
mutex_unlock(&local->iflist_mtx);
}
void ieee80211_offchannel_return(struct ieee80211_local *local,
bool enable_beaconing)
bool enable_beaconing,
bool offchannel_ps_disable)
{
struct ieee80211_sub_if_data *sdata;
@@ -161,7 +166,8 @@ void ieee80211_offchannel_return(struct ieee80211_local *local,
continue;
/* Tell AP we're back */
if (sdata->vif.type == NL80211_IFTYPE_STATION) {
if (offchannel_ps_disable &&
sdata->vif.type == NL80211_IFTYPE_STATION) {
if (sdata->u.mgd.associated)
ieee80211_offchannel_ps_disable(sdata);
}
@@ -181,7 +187,7 @@ void ieee80211_offchannel_return(struct ieee80211_local *local,
netif_tx_wake_all_queues(sdata->dev);
}
/* re-enable beaconing */
/* Check to see if we should re-enable beaconing */
if (enable_beaconing &&
(sdata->vif.type == NL80211_IFTYPE_AP ||
sdata->vif.type == NL80211_IFTYPE_ADHOC ||