From f81a9dedaff434604c7fc3d9c299d277b76db0a8 Mon Sep 17 00:00:00 2001 From: Thomas Pedersen Date: Thu, 13 Jun 2013 15:54:41 -0700 Subject: [PATCH] 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 [fix comment position] Signed-off-by: Johannes Berg --- net/mac80211/ieee80211_i.h | 1 + net/mac80211/mesh.c | 53 +++++++++++++++++++++++++++++--------- net/mac80211/mesh.h | 2 ++ 3 files changed, 44 insertions(+), 12 deletions(-) diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h index a4dfb0be53d7..194be3de16dd 100644 --- a/net/mac80211/ieee80211_i.h +++ b/net/mac80211/ieee80211_i.h @@ -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; diff --git a/net/mac80211/mesh.c b/net/mac80211/mesh.c index 6c33af482df4..d5dea94216e4 100644 --- a/net/mac80211/mesh.c +++ b/net/mac80211/mesh.c @@ -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); } diff --git a/net/mac80211/mesh.h b/net/mac80211/mesh.h index 01a28bca6e9b..2bc7fd2f787d 100644 --- a/net/mac80211/mesh.h +++ b/net/mac80211/mesh.h @@ -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, }; /** -- 2.34.1