This patch addresses a long standing issue of the driver with the mac80211 .flush() callback. Since implementing the .flush() callback a number of issues have been fixed, but a WARN_ON_ONCE() was still triggered because the flush takes too much time. The flush now makes use of a waitqueue and still has a timeout on which a warning is given. bugzilla: 42840 <https://bugzilla.kernel.org/show_bug.cgi?id=42840> bugzilla@redhat: <https://bugzilla.redhat.com/show_bug.cgi?id=799168> bugzilla@redhat: <https://bugzilla.redhat.com/show_bug.cgi?id=787649> Cc: stable <stable@xxxxxxxxxxxxxxx> Cc: Jonathan Nieder <jrnieder@xxxxxxxxx> Cc: Stanislaw Gruszka <sgruszka@xxxxxxxxxx> Cc: Camaleón <noelamac@xxxxxxxxx> Cc: Milan Bouchet-Valat <nalimilan@xxxxxxxxxxxxxxxx> Reviewed-by: Pieter-Paul Giesberts <pieterpg@xxxxxxxxxxxx> Reviewed-by: Hante Meuleman <meuleman@xxxxxxxxxxxx> Signed-off-by: Arend van Spriel <arend@xxxxxxxxxxxx> --- .../net/wireless/brcm80211/brcmsmac/mac80211_if.c | 41 +++++++++++++------- .../net/wireless/brcm80211/brcmsmac/mac80211_if.h | 3 +- drivers/net/wireless/brcm80211/brcmsmac/main.c | 21 +++------- drivers/net/wireless/brcm80211/brcmsmac/pub.h | 4 +- 4 files changed, 37 insertions(+), 32 deletions(-) diff --git a/drivers/net/wireless/brcm80211/brcmsmac/mac80211_if.c b/drivers/net/wireless/brcm80211/brcmsmac/mac80211_if.c index a5edebe..56c419b 100644 --- a/drivers/net/wireless/brcm80211/brcmsmac/mac80211_if.c +++ b/drivers/net/wireless/brcm80211/brcmsmac/mac80211_if.c @@ -35,6 +35,7 @@ #include "main.h" #define N_TX_QUEUES 4 /* #tx queues on mac80211<->driver interface */ +#define BRCMS_FLUSH_TIMEOUT 100 /* msec */ /* Flags we support */ #define MAC_FILTERS (FIF_PROMISC_IN_BSS | \ @@ -693,16 +694,35 @@ static void brcms_ops_rfkill_poll(struct ieee80211_hw *hw) wiphy_rfkill_set_hw_state(wl->pub->ieee_hw->wiphy, blocked); } +static bool brcms_tx_flush_completed(struct brcms_info *wl) +{ + bool result; + + spin_lock_bh(&wl->lock); + result = brcms_c_tx_flush_completed(wl->wlc); + spin_unlock_bh(&wl->lock); + return result; +} + static void brcms_ops_flush(struct ieee80211_hw *hw, bool drop) { struct brcms_info *wl = hw->priv; + int ret; no_printk("%s: drop = %s\n", __func__, drop ? "true" : "false"); - /* wait for packet queue and dma fifos to run empty */ - spin_lock_bh(&wl->lock); - brcms_c_wait_for_tx_completion(wl->wlc, drop); - spin_unlock_bh(&wl->lock); + ieee80211_stop_queues(hw); + if (drop) { + spin_lock_bh(&wl->lock); + brcms_c_pktq_flush(wl->wlc); + spin_unlock_bh(&wl->lock); + } + ret = wait_event_timeout(wl->tx_flush_wq, + brcms_tx_flush_completed(wl), + msecs_to_jiffies(BRCMS_FLUSH_TIMEOUT)); + + ieee80211_wake_queues(hw); + WARN_ON(!ret); } static const struct ieee80211_ops brcms_ops = { @@ -757,6 +777,7 @@ void brcms_dpc(unsigned long data) done: spin_unlock_bh(&wl->lock); + wake_up(&wl->tx_flush_wq); } /* @@ -1008,6 +1029,8 @@ static struct brcms_info *brcms_attach(struct bcma_device *pdev) atomic_set(&wl->callbacks, 0); + init_waitqueue_head(&wl->tx_flush_wq); + /* setup the bottom half handler */ tasklet_init(&wl->tasklet, brcms_dpc, (unsigned long) wl); @@ -1594,13 +1617,3 @@ bool brcms_rfkill_set_hw_state(struct brcms_info *wl) spin_lock_bh(&wl->lock); return blocked; } - -/* - * precondition: perimeter lock has been acquired - */ -void brcms_msleep(struct brcms_info *wl, uint ms) -{ - spin_unlock_bh(&wl->lock); - msleep(ms); - spin_lock_bh(&wl->lock); -} diff --git a/drivers/net/wireless/brcm80211/brcmsmac/mac80211_if.h b/drivers/net/wireless/brcm80211/brcmsmac/mac80211_if.h index 9358bd5..947ccac 100644 --- a/drivers/net/wireless/brcm80211/brcmsmac/mac80211_if.h +++ b/drivers/net/wireless/brcm80211/brcmsmac/mac80211_if.h @@ -68,6 +68,8 @@ struct brcms_info { spinlock_t lock; /* per-device perimeter lock */ spinlock_t isr_lock; /* per-device ISR synchronization lock */ + /* tx flush */ + wait_queue_head_t tx_flush_wq; /* timer related fields */ atomic_t callbacks; /* # outstanding callback functions */ @@ -100,7 +102,6 @@ extern struct brcms_timer *brcms_init_timer(struct brcms_info *wl, extern void brcms_free_timer(struct brcms_timer *timer); extern void brcms_add_timer(struct brcms_timer *timer, uint ms, int periodic); extern bool brcms_del_timer(struct brcms_timer *timer); -extern void brcms_msleep(struct brcms_info *wl, uint ms); extern void brcms_dpc(unsigned long data); extern void brcms_timer(struct brcms_timer *t); extern void brcms_fatal_error(struct brcms_info *wl); diff --git a/drivers/net/wireless/brcm80211/brcmsmac/main.c b/drivers/net/wireless/brcm80211/brcmsmac/main.c index 03ca653..ee44126 100644 --- a/drivers/net/wireless/brcm80211/brcmsmac/main.c +++ b/drivers/net/wireless/brcm80211/brcmsmac/main.c @@ -7979,23 +7979,14 @@ int brcms_c_get_curband(struct brcms_c_info *wlc) return wlc->band->bandunit; } -void brcms_c_wait_for_tx_completion(struct brcms_c_info *wlc, bool drop) +void brcms_c_pktq_flush(struct brcms_c_info *wlc) { - int timeout = 20; - - /* flush packet queue when requested */ - if (drop) - brcmu_pktq_flush(&wlc->pkt_queue->q, false, NULL, NULL); - - /* wait for queue and DMA fifos to run dry */ - while (!pktq_empty(&wlc->pkt_queue->q) || brcms_txpktpendtot(wlc) > 0) { - brcms_msleep(wlc->wl, 1); - - if (--timeout == 0) - break; - } + brcmu_pktq_flush(&wlc->pkt_queue->q, false, NULL, NULL); +} - WARN_ON_ONCE(timeout == 0); +bool brcms_c_tx_flush_completed(struct brcms_c_info *wlc) +{ + return pktq_empty(&wlc->pkt_queue->q) && !brcms_txpktpendtot(wlc); } void brcms_c_set_beacon_listen_interval(struct brcms_c_info *wlc, u8 interval) diff --git a/drivers/net/wireless/brcm80211/brcmsmac/pub.h b/drivers/net/wireless/brcm80211/brcmsmac/pub.h index 5855f4f..59caa1c 100644 --- a/drivers/net/wireless/brcm80211/brcmsmac/pub.h +++ b/drivers/net/wireless/brcm80211/brcmsmac/pub.h @@ -350,8 +350,6 @@ extern void brcms_c_associate_upd(struct brcms_c_info *wlc, bool state); extern void brcms_c_scan_start(struct brcms_c_info *wlc); extern void brcms_c_scan_stop(struct brcms_c_info *wlc); extern int brcms_c_get_curband(struct brcms_c_info *wlc); -extern void brcms_c_wait_for_tx_completion(struct brcms_c_info *wlc, - bool drop); extern int brcms_c_set_channel(struct brcms_c_info *wlc, u16 channel); extern int brcms_c_set_rate_limit(struct brcms_c_info *wlc, u16 srl, u16 lrl); extern void brcms_c_get_current_rateset(struct brcms_c_info *wlc, @@ -368,5 +366,7 @@ extern int brcms_c_set_tx_power(struct brcms_c_info *wlc, int txpwr); extern int brcms_c_get_tx_power(struct brcms_c_info *wlc); extern bool brcms_c_check_radio_disabled(struct brcms_c_info *wlc); extern void brcms_c_mute(struct brcms_c_info *wlc, bool on); +extern void brcms_c_pktq_flush(struct brcms_c_info *wlc); +extern bool brcms_c_tx_flush_completed(struct brcms_c_info *wlc); #endif /* _BRCM_PUB_H_ */ -- 1.7.9.5 -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
