ath9k: remove sc->rx.rxbuflock to fix a deadlock

The commit "ath9k: fix rx flush handling" added a deadlock that happens
because ath_rx_tasklet is called in a section that has already taken the
rx buffer lock.

It seems that the only purpose of the rxbuflock was a band-aid fix to the
reset vs rx tasklet race, which has been properly fixed in the commit
"ath9k: add a better fix for the rx tasklet vs rx flush race".

Now that the fix is in, we can safely remove the lock to avoid such issues.

Cc: stable@vger.kernel.org
Reported-by: Sujith Manoharan <c_manoha@qca.qualcomm.com>
Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
This commit is contained in:
Felix Fietkau 2013-01-14 10:50:15 +01:00 committed by John W. Linville
parent a1fe52801a
commit 463e3ed3ea
2 changed files with 0 additions and 14 deletions

View File

@ -317,7 +317,6 @@ struct ath_rx {
u32 *rxlink;
u32 num_pkts;
unsigned int rxfilter;
spinlock_t rxbuflock;
struct list_head rxbuf;
struct ath_descdma rxdma;
struct ath_buf *rx_bufptr;

View File

@ -254,8 +254,6 @@ rx_init_fail:
static void ath_edma_start_recv(struct ath_softc *sc)
{
spin_lock_bh(&sc->rx.rxbuflock);
ath9k_hw_rxena(sc->sc_ah);
ath_rx_addbuffer_edma(sc, ATH9K_RX_QUEUE_HP,
@ -267,8 +265,6 @@ static void ath_edma_start_recv(struct ath_softc *sc)
ath_opmode_init(sc);
ath9k_hw_startpcureceive(sc->sc_ah, !!(sc->hw->conf.flags & IEEE80211_CONF_OFFCHANNEL));
spin_unlock_bh(&sc->rx.rxbuflock);
}
static void ath_edma_stop_recv(struct ath_softc *sc)
@ -285,7 +281,6 @@ int ath_rx_init(struct ath_softc *sc, int nbufs)
int error = 0;
spin_lock_init(&sc->sc_pcu_lock);
spin_lock_init(&sc->rx.rxbuflock);
common->rx_bufsize = IEEE80211_MAX_MPDU_LEN / 2 +
sc->sc_ah->caps.rx_status_len;
@ -446,7 +441,6 @@ int ath_startrecv(struct ath_softc *sc)
return 0;
}
spin_lock_bh(&sc->rx.rxbuflock);
if (list_empty(&sc->rx.rxbuf))
goto start_recv;
@ -467,8 +461,6 @@ start_recv:
ath_opmode_init(sc);
ath9k_hw_startpcureceive(ah, !!(sc->hw->conf.flags & IEEE80211_CONF_OFFCHANNEL));
spin_unlock_bh(&sc->rx.rxbuflock);
return 0;
}
@ -484,7 +476,6 @@ bool ath_stoprecv(struct ath_softc *sc)
struct ath_hw *ah = sc->sc_ah;
bool stopped, reset = false;
spin_lock_bh(&sc->rx.rxbuflock);
ath9k_hw_abortpcurecv(ah);
ath9k_hw_setrxfilter(ah, 0);
stopped = ath9k_hw_stopdmarecv(ah, &reset);
@ -495,7 +486,6 @@ bool ath_stoprecv(struct ath_softc *sc)
ath_edma_stop_recv(sc);
else
sc->rx.rxlink = NULL;
spin_unlock_bh(&sc->rx.rxbuflock);
if (!(ah->ah_flags & AH_UNPLUGGED) &&
unlikely(!stopped)) {
@ -1059,7 +1049,6 @@ int ath_rx_tasklet(struct ath_softc *sc, int flush, bool hp)
dma_type = DMA_FROM_DEVICE;
qtype = hp ? ATH9K_RX_QUEUE_HP : ATH9K_RX_QUEUE_LP;
spin_lock_bh(&sc->rx.rxbuflock);
tsf = ath9k_hw_gettsf64(ah);
tsf_lower = tsf & 0xffffffff;
@ -1254,8 +1243,6 @@ requeue:
}
} while (1);
spin_unlock_bh(&sc->rx.rxbuflock);
if (!(ah->imask & ATH9K_INT_RXEOL)) {
ah->imask |= (ATH9K_INT_RXEOL | ATH9K_INT_RXORN);
ath9k_hw_set_interrupts(ah);