From c9cb14a64c32f890d5a0649cb7d81dbfece33056 Mon Sep 17 00:00:00 2001 From: Chaya Rachel Ivgi Date: Thu, 3 Mar 2016 15:35:34 +0200 Subject: [PATCH] iwlwifi: mvm: add support for async rx handler without hold the mutex When running async rx handler the framework holds the mvm->mutex before starting the async handler, that might cause a deadlock in case the handler calls to ops that lock the mutex as well. Add support for running async rx handler without hold the mutex before activating the handler. Signed-off-by: Chaya Rachel Ivgi Signed-off-by: Emmanuel Grumbach --- drivers/net/wireless/intel/iwlwifi/mvm/ops.c | 114 ++++++++++++------- 1 file changed, 73 insertions(+), 41 deletions(-) diff --git a/drivers/net/wireless/intel/iwlwifi/mvm/ops.c b/drivers/net/wireless/intel/iwlwifi/mvm/ops.c index 4322e8ed1159..5e8ab796d5bc 100644 --- a/drivers/net/wireless/intel/iwlwifi/mvm/ops.c +++ b/drivers/net/wireless/intel/iwlwifi/mvm/ops.c @@ -205,79 +205,107 @@ static void iwl_mvm_nic_config(struct iwl_op_mode *op_mode) ~APMG_PS_CTRL_EARLY_PWR_OFF_RESET_DIS); } +/** + * enum iwl_rx_handler_context context for Rx handler + * @RX_HANDLER_SYNC : this means that it will be called in the Rx path + * which can't acquire mvm->mutex. + * @RX_HANDLER_ASYNC_LOCKED : If the handler needs to hold mvm->mutex + * (and only in this case!), it should be set as ASYNC. In that case, + * it will be called from a worker with mvm->mutex held. + * @RX_HANDLER_ASYNC_UNLOCKED : in case the handler needs to lock the + * mutex itself, it will be called from a worker without mvm->mutex held. + */ +enum iwl_rx_handler_context { + RX_HANDLER_SYNC, + RX_HANDLER_ASYNC_LOCKED, + RX_HANDLER_ASYNC_UNLOCKED, +}; + +/** + * struct iwl_rx_handlers handler for FW notification + * @cmd_id: command id + * @context: see &iwl_rx_handler_context + * @fn: the function is called when notification is received + */ struct iwl_rx_handlers { u16 cmd_id; - bool async; + enum iwl_rx_handler_context context; void (*fn)(struct iwl_mvm *mvm, struct iwl_rx_cmd_buffer *rxb); }; -#define RX_HANDLER(_cmd_id, _fn, _async) \ - { .cmd_id = _cmd_id , .fn = _fn , .async = _async } -#define RX_HANDLER_GRP(_grp, _cmd, _fn, _async) \ - { .cmd_id = WIDE_ID(_grp, _cmd), .fn = _fn, .async = _async } +#define RX_HANDLER(_cmd_id, _fn, _context) \ + { .cmd_id = _cmd_id, .fn = _fn, .context = _context } +#define RX_HANDLER_GRP(_grp, _cmd, _fn, _context) \ + { .cmd_id = WIDE_ID(_grp, _cmd), .fn = _fn, .context = _context } /* * Handlers for fw notifications * Convention: RX_HANDLER(CMD_NAME, iwl_mvm_rx_CMD_NAME * This list should be in order of frequency for performance purposes. * - * The handler can be SYNC - this means that it will be called in the Rx path - * which can't acquire mvm->mutex. If the handler needs to hold mvm->mutex (and - * only in this case!), it should be set as ASYNC. In that case, it will be - * called from a worker with mvm->mutex held. + * The handler can be one from three contexts, see &iwl_rx_handler_context */ static const struct iwl_rx_handlers iwl_mvm_rx_handlers[] = { - RX_HANDLER(TX_CMD, iwl_mvm_rx_tx_cmd, false), - RX_HANDLER(BA_NOTIF, iwl_mvm_rx_ba_notif, false), - - RX_HANDLER(BT_PROFILE_NOTIFICATION, iwl_mvm_rx_bt_coex_notif, true), - RX_HANDLER(BEACON_NOTIFICATION, iwl_mvm_rx_beacon_notif, true), - RX_HANDLER(STATISTICS_NOTIFICATION, iwl_mvm_rx_statistics, true), + RX_HANDLER(TX_CMD, iwl_mvm_rx_tx_cmd, RX_HANDLER_SYNC), + RX_HANDLER(BA_NOTIF, iwl_mvm_rx_ba_notif, RX_HANDLER_SYNC), + + RX_HANDLER(BT_PROFILE_NOTIFICATION, iwl_mvm_rx_bt_coex_notif, + RX_HANDLER_ASYNC_LOCKED), + RX_HANDLER(BEACON_NOTIFICATION, iwl_mvm_rx_beacon_notif, + RX_HANDLER_ASYNC_LOCKED), + RX_HANDLER(STATISTICS_NOTIFICATION, iwl_mvm_rx_statistics, + RX_HANDLER_ASYNC_LOCKED), RX_HANDLER(ANTENNA_COUPLING_NOTIFICATION, - iwl_mvm_rx_ant_coupling_notif, true), + iwl_mvm_rx_ant_coupling_notif, RX_HANDLER_ASYNC_LOCKED), RX_HANDLER(BA_WINDOW_STATUS_NOTIFICATION_ID, - iwl_mvm_window_status_notif, false), + iwl_mvm_window_status_notif, RX_HANDLER_SYNC), - RX_HANDLER(TIME_EVENT_NOTIFICATION, iwl_mvm_rx_time_event_notif, false), - RX_HANDLER(MCC_CHUB_UPDATE_CMD, iwl_mvm_rx_chub_update_mcc, true), + RX_HANDLER(TIME_EVENT_NOTIFICATION, iwl_mvm_rx_time_event_notif, + RX_HANDLER_SYNC), + RX_HANDLER(MCC_CHUB_UPDATE_CMD, iwl_mvm_rx_chub_update_mcc, + RX_HANDLER_ASYNC_LOCKED), - RX_HANDLER(EOSP_NOTIFICATION, iwl_mvm_rx_eosp_notif, false), + RX_HANDLER(EOSP_NOTIFICATION, iwl_mvm_rx_eosp_notif, RX_HANDLER_SYNC), RX_HANDLER(SCAN_ITERATION_COMPLETE, - iwl_mvm_rx_lmac_scan_iter_complete_notif, false), + iwl_mvm_rx_lmac_scan_iter_complete_notif, RX_HANDLER_SYNC), RX_HANDLER(SCAN_OFFLOAD_COMPLETE, - iwl_mvm_rx_lmac_scan_complete_notif, true), + iwl_mvm_rx_lmac_scan_complete_notif, + RX_HANDLER_ASYNC_LOCKED), RX_HANDLER(MATCH_FOUND_NOTIFICATION, iwl_mvm_rx_scan_match_found, - false), + RX_HANDLER_SYNC), RX_HANDLER(SCAN_COMPLETE_UMAC, iwl_mvm_rx_umac_scan_complete_notif, - true), + RX_HANDLER_ASYNC_LOCKED), RX_HANDLER(SCAN_ITERATION_COMPLETE_UMAC, - iwl_mvm_rx_umac_scan_iter_complete_notif, false), + iwl_mvm_rx_umac_scan_iter_complete_notif, RX_HANDLER_SYNC), - RX_HANDLER(CARD_STATE_NOTIFICATION, iwl_mvm_rx_card_state_notif, false), + RX_HANDLER(CARD_STATE_NOTIFICATION, iwl_mvm_rx_card_state_notif, + RX_HANDLER_SYNC), RX_HANDLER(MISSED_BEACONS_NOTIFICATION, iwl_mvm_rx_missed_beacons_notif, - false), + RX_HANDLER_SYNC), - RX_HANDLER(REPLY_ERROR, iwl_mvm_rx_fw_error, false), + RX_HANDLER(REPLY_ERROR, iwl_mvm_rx_fw_error, RX_HANDLER_SYNC), RX_HANDLER(PSM_UAPSD_AP_MISBEHAVING_NOTIFICATION, - iwl_mvm_power_uapsd_misbehaving_ap_notif, false), - RX_HANDLER(DTS_MEASUREMENT_NOTIFICATION, iwl_mvm_temp_notif, true), + iwl_mvm_power_uapsd_misbehaving_ap_notif, RX_HANDLER_SYNC), + RX_HANDLER(DTS_MEASUREMENT_NOTIFICATION, iwl_mvm_temp_notif, + RX_HANDLER_ASYNC_LOCKED), RX_HANDLER_GRP(PHY_OPS_GROUP, DTS_MEASUREMENT_NOTIF_WIDE, - iwl_mvm_temp_notif, true), + iwl_mvm_temp_notif, RX_HANDLER_ASYNC_LOCKED), RX_HANDLER_GRP(PHY_OPS_GROUP, CT_KILL_NOTIFICATION, - iwl_mvm_ct_kill_notif, false), + iwl_mvm_ct_kill_notif, RX_HANDLER_SYNC), RX_HANDLER(TDLS_CHANNEL_SWITCH_NOTIFICATION, iwl_mvm_rx_tdls_notif, - true), - RX_HANDLER(MFUART_LOAD_NOTIFICATION, iwl_mvm_rx_mfuart_notif, false), - RX_HANDLER(TOF_NOTIFICATION, iwl_mvm_tof_resp_handler, true), + RX_HANDLER_ASYNC_LOCKED), + RX_HANDLER(MFUART_LOAD_NOTIFICATION, iwl_mvm_rx_mfuart_notif, + RX_HANDLER_SYNC), + RX_HANDLER(TOF_NOTIFICATION, iwl_mvm_tof_resp_handler, + RX_HANDLER_ASYNC_LOCKED), RX_HANDLER_GRP(PROT_OFFLOAD_GROUP, STORED_BEACON_NTF, - iwl_mvm_rx_stored_beacon_notif, false), + iwl_mvm_rx_stored_beacon_notif, RX_HANDLER_SYNC), RX_HANDLER_GRP(DATA_PATH_GROUP, MU_GROUP_MGMT_NOTIF, - iwl_mvm_mu_mimo_grp_notif, false), - + iwl_mvm_mu_mimo_grp_notif, RX_HANDLER_SYNC), }; #undef RX_HANDLER #undef RX_HANDLER_GRP @@ -743,6 +771,7 @@ static void iwl_op_mode_mvm_stop(struct iwl_op_mode *op_mode) struct iwl_async_handler_entry { struct list_head list; struct iwl_rx_cmd_buffer rxb; + enum iwl_rx_handler_context context; void (*fn)(struct iwl_mvm *mvm, struct iwl_rx_cmd_buffer *rxb); }; @@ -769,7 +798,6 @@ static void iwl_mvm_async_handlers_wk(struct work_struct *wk) INIT_LIST_HEAD(&local_list); /* Ensure that we are not in stop flow (check iwl_mvm_mac_stop) */ - mutex_lock(&mvm->mutex); /* * Sync with Rx path with a lock. Remove all the entries from this list, @@ -780,12 +808,15 @@ static void iwl_mvm_async_handlers_wk(struct work_struct *wk) spin_unlock_bh(&mvm->async_handlers_lock); list_for_each_entry_safe(entry, tmp, &local_list, list) { + if (entry->context == RX_HANDLER_ASYNC_LOCKED) + mutex_lock(&mvm->mutex); entry->fn(mvm, &entry->rxb); iwl_free_rxb(&entry->rxb); list_del(&entry->list); + if (entry->context == RX_HANDLER_ASYNC_LOCKED) + mutex_unlock(&mvm->mutex); kfree(entry); } - mutex_unlock(&mvm->mutex); } static inline void iwl_mvm_rx_check_trigger(struct iwl_mvm *mvm, @@ -842,7 +873,7 @@ static void iwl_mvm_rx_common(struct iwl_mvm *mvm, if (rx_h->cmd_id != WIDE_ID(pkt->hdr.group_id, pkt->hdr.cmd)) continue; - if (!rx_h->async) { + if (rx_h->context == RX_HANDLER_SYNC) { rx_h->fn(mvm, rxb); return; } @@ -856,6 +887,7 @@ static void iwl_mvm_rx_common(struct iwl_mvm *mvm, entry->rxb._offset = rxb->_offset; entry->rxb._rx_page_order = rxb->_rx_page_order; entry->fn = rx_h->fn; + entry->context = rx_h->context; spin_lock(&mvm->async_handlers_lock); list_add_tail(&entry->list, &mvm->async_handlers_list); spin_unlock(&mvm->async_handlers_lock); -- GitLab