mac80211: update mesh beacon on workqueue

Instead of updating the mesh beacon immediately when
requested (which would require the sdata_lock()), defer it
to the mac80211 workqueue.

Fixes yet another deadlock on calling sta_info_flush()
with the sdata_lock() held from ieee80211_stop_mesh(). We
could just drop the sdata_lock() around the
mesh_sta_cleanup() call, but this path is also taken from
several non-locked error paths.

Signed-off-by: Thomas Pedersen <thomas@cozybit.com>
[fix comment position]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
This commit is contained in:
Thomas Pedersen 2013-06-13 15:54:41 -07:00 committed by Johannes Berg
parent a1193be83b
commit f81a9dedaf
3 changed files with 44 additions and 12 deletions

View File

@ -544,6 +544,7 @@ struct ieee80211_if_mesh {
struct timer_list mesh_path_root_timer;
unsigned long wrkq_flags;
unsigned long mbss_changed;
u8 mesh_id[IEEE80211_MAX_MESH_ID_LEN];
size_t mesh_id_len;

View File

@ -161,11 +161,8 @@ void mesh_sta_cleanup(struct sta_info *sta)
del_timer_sync(&sta->plink_timer);
}
if (changed) {
sdata_lock(sdata);
if (changed)
ieee80211_mbss_info_change_notify(sdata, changed);
sdata_unlock(sdata);
}
}
int mesh_rmc_init(struct ieee80211_sub_if_data *sdata)
@ -719,14 +716,18 @@ ieee80211_mesh_rebuild_beacon(struct ieee80211_sub_if_data *sdata)
void ieee80211_mbss_info_change_notify(struct ieee80211_sub_if_data *sdata,
u32 changed)
{
if (sdata->vif.bss_conf.enable_beacon &&
(changed & (BSS_CHANGED_BEACON |
BSS_CHANGED_HT |
BSS_CHANGED_BASIC_RATES |
BSS_CHANGED_BEACON_INT)))
if (ieee80211_mesh_rebuild_beacon(sdata))
return;
ieee80211_bss_info_change_notify(sdata, changed);
struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
unsigned long bits = changed;
u32 bit;
if (!bits)
return;
/* if we race with running work, worst case this work becomes a noop */
for_each_set_bit(bit, &bits, sizeof(changed) * BITS_PER_BYTE)
set_bit(bit, &ifmsh->mbss_changed);
set_bit(MESH_WORK_MBSS_CHANGED, &ifmsh->wrkq_flags);
ieee80211_queue_work(&sdata->local->hw, &sdata->work);
}
int ieee80211_start_mesh(struct ieee80211_sub_if_data *sdata)
@ -799,6 +800,10 @@ void ieee80211_stop_mesh(struct ieee80211_sub_if_data *sdata)
del_timer_sync(&sdata->u.mesh.mesh_path_root_timer);
del_timer_sync(&sdata->u.mesh.mesh_path_timer);
/* clear any mesh work (for next join) we may have accrued */
ifmsh->wrkq_flags = 0;
ifmsh->mbss_changed = 0;
local->fif_other_bss--;
atomic_dec(&local->iff_allmultis);
ieee80211_configure_filter(local);
@ -965,6 +970,28 @@ out:
sdata_unlock(sdata);
}
static void mesh_bss_info_changed(struct ieee80211_sub_if_data *sdata)
{
struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
u32 bit, changed = 0;
for_each_set_bit(bit, &ifmsh->mbss_changed,
sizeof(changed) * BITS_PER_BYTE) {
clear_bit(bit, &ifmsh->mbss_changed);
changed |= BIT(bit);
}
if (sdata->vif.bss_conf.enable_beacon &&
(changed & (BSS_CHANGED_BEACON |
BSS_CHANGED_HT |
BSS_CHANGED_BASIC_RATES |
BSS_CHANGED_BEACON_INT)))
if (ieee80211_mesh_rebuild_beacon(sdata))
return;
ieee80211_bss_info_change_notify(sdata, changed);
}
void ieee80211_mesh_work(struct ieee80211_sub_if_data *sdata)
{
struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
@ -995,6 +1022,8 @@ void ieee80211_mesh_work(struct ieee80211_sub_if_data *sdata)
if (test_and_clear_bit(MESH_WORK_DRIFT_ADJUST, &ifmsh->wrkq_flags))
mesh_sync_adjust_tbtt(sdata);
if (test_and_clear_bit(MESH_WORK_MBSS_CHANGED, &ifmsh->wrkq_flags))
mesh_bss_info_changed(sdata);
out:
sdata_unlock(sdata);
}

View File

@ -58,6 +58,7 @@ enum mesh_path_flags {
* @MESH_WORK_ROOT: the mesh root station needs to send a frame
* @MESH_WORK_DRIFT_ADJUST: time to compensate for clock drift relative to other
* mesh nodes
* @MESH_WORK_MBSS_CHANGED: rebuild beacon and notify driver of BSS changes
*/
enum mesh_deferred_task_flags {
MESH_WORK_HOUSEKEEPING,
@ -65,6 +66,7 @@ enum mesh_deferred_task_flags {
MESH_WORK_GROW_MPP_TABLE,
MESH_WORK_ROOT,
MESH_WORK_DRIFT_ADJUST,
MESH_WORK_MBSS_CHANGED,
};
/**