2012-06-04 14:55:14

by Sujith Manoharan

[permalink] [raw]
Subject: [PATCH 4/7] ath9k: Use atomic operations

The 'sc_flags' variable is being used in a number of places
with no locking whatsoever. This patch converts the usage
of sc_flags to atomic ops.

Signed-off-by: Sujith Manoharan <[email protected]>
---
drivers/net/wireless/ath/ath9k/ahb.c | 2 +-
drivers/net/wireless/ath/ath9k/ath9k.h | 16 ++++++------
drivers/net/wireless/ath/ath9k/beacon.c | 18 ++++++-------
drivers/net/wireless/ath/ath9k/debug.c | 6 ++---
drivers/net/wireless/ath/ath9k/link.c | 4 +--
drivers/net/wireless/ath/ath9k/main.c | 42 +++++++++++++++----------------
drivers/net/wireless/ath/ath9k/pci.c | 2 +-
drivers/net/wireless/ath/ath9k/recv.c | 10 ++++----
drivers/net/wireless/ath/ath9k/xmit.c | 2 +-
9 files changed, 52 insertions(+), 50 deletions(-)

diff --git a/drivers/net/wireless/ath/ath9k/ahb.c b/drivers/net/wireless/ath/ath9k/ahb.c
index 5e47ca6..4a4e8a2 100644
--- a/drivers/net/wireless/ath/ath9k/ahb.c
+++ b/drivers/net/wireless/ath/ath9k/ahb.c
@@ -126,7 +126,7 @@ static int ath_ahb_probe(struct platform_device *pdev)
sc->irq = irq;

/* Will be cleared in ath9k_start() */
- sc->sc_flags |= SC_OP_INVALID;
+ set_bit(SC_OP_INVALID, &sc->sc_flags);

ret = request_irq(irq, ath_isr, IRQF_SHARED, "ath9k", sc);
if (ret) {
diff --git a/drivers/net/wireless/ath/ath9k/ath9k.h b/drivers/net/wireless/ath/ath9k/ath9k.h
index 4c2ce45..ae43de1 100644
--- a/drivers/net/wireless/ath/ath9k/ath9k.h
+++ b/drivers/net/wireless/ath/ath9k/ath9k.h
@@ -604,12 +604,14 @@ void ath_ant_comb_update(struct ath_softc *sc);
#define ATH_TXPOWER_MAX 100 /* .5 dBm units */
#define ATH_RATE_DUMMY_MARKER 0

-#define SC_OP_INVALID BIT(0)
-#define SC_OP_BEACONS BIT(1)
-#define SC_OP_RXFLUSH BIT(2)
-#define SC_OP_TSF_RESET BIT(3)
-#define SC_OP_ANI_RUN BIT(4)
-#define SC_OP_PRIM_STA_VIF BIT(5)
+enum sc_op_flags {
+ SC_OP_INVALID,
+ SC_OP_BEACONS,
+ SC_OP_RXFLUSH,
+ SC_OP_TSF_RESET,
+ SC_OP_ANI_RUN,
+ SC_OP_PRIM_STA_VIF,
+};

/* Powersave flags */
#define PS_WAIT_FOR_BEACON BIT(0)
@@ -655,9 +657,9 @@ struct ath_softc {
struct completion paprd_complete;

unsigned int hw_busy_count;
+ unsigned long sc_flags;

u32 intrstatus;
- u32 sc_flags; /* SC_OP_* */
u16 ps_flags; /* PS_* */
u16 curtxpow;
bool ps_enabled;
diff --git a/drivers/net/wireless/ath/ath9k/beacon.c b/drivers/net/wireless/ath/ath9k/beacon.c
index 11bc55e..6afb470 100644
--- a/drivers/net/wireless/ath/ath9k/beacon.c
+++ b/drivers/net/wireless/ath/ath9k/beacon.c
@@ -387,7 +387,7 @@ void ath_beacon_tasklet(unsigned long data)
} else if (sc->beacon.bmisscnt >= BSTUCK_THRESH) {
ath_dbg(common, BSTUCK, "beacon is officially stuck\n");
sc->beacon.bmisscnt = 0;
- sc->sc_flags |= SC_OP_TSF_RESET;
+ set_bit(SC_OP_TSF_RESET, &sc->sc_flags);
ieee80211_queue_work(sc->hw, &sc->hw_reset_work);
}

@@ -477,16 +477,16 @@ static void ath9k_beacon_init(struct ath_softc *sc,
u32 next_beacon,
u32 beacon_period)
{
- if (sc->sc_flags & SC_OP_TSF_RESET) {
+ if (test_bit(SC_OP_TSF_RESET, &sc->sc_flags)) {
ath9k_ps_wakeup(sc);
ath9k_hw_reset_tsf(sc->sc_ah);
}

ath9k_hw_beaconinit(sc->sc_ah, next_beacon, beacon_period);

- if (sc->sc_flags & SC_OP_TSF_RESET) {
+ if (test_bit(SC_OP_TSF_RESET, &sc->sc_flags)) {
ath9k_ps_restore(sc);
- sc->sc_flags &= ~SC_OP_TSF_RESET;
+ clear_bit(SC_OP_TSF_RESET, &sc->sc_flags);
}
}

@@ -516,7 +516,7 @@ static void ath_beacon_config_ap(struct ath_softc *sc,
/* Set the computed AP beacon timers */

ath9k_hw_disable_interrupts(ah);
- sc->sc_flags |= SC_OP_TSF_RESET;
+ set_bit(SC_OP_TSF_RESET, &sc->sc_flags);
ath9k_beacon_init(sc, nexttbtt, intval);
sc->beacon.bmisscnt = 0;
ath9k_hw_set_interrupts(ah);
@@ -659,7 +659,7 @@ static void ath_beacon_config_adhoc(struct ath_softc *sc,
u32 tsf, intval, nexttbtt;

ath9k_reset_beacon_status(sc);
- if (!(sc->sc_flags & SC_OP_BEACONS))
+ if (!test_bit(SC_OP_BEACONS, &sc->sc_flags))
ath9k_hw_settsf64(ah, sc->beacon.bc_tstamp);

intval = TU_TO_USEC(conf->beacon_interval);
@@ -724,7 +724,7 @@ static bool ath9k_allow_beacon_config(struct ath_softc *sc,
*/
if ((sc->sc_ah->opmode == NL80211_IFTYPE_STATION) &&
(vif->type == NL80211_IFTYPE_STATION) &&
- (sc->sc_flags & SC_OP_BEACONS) &&
+ test_bit(SC_OP_BEACONS, &sc->sc_flags) &&
!avp->primary_sta_vif) {
ath_dbg(common, CONFIG,
"Beacon already configured for a station interface\n");
@@ -810,7 +810,7 @@ void ath_set_beacon(struct ath_softc *sc)
return;
}

- sc->sc_flags |= SC_OP_BEACONS;
+ set_bit(SC_OP_BEACONS, &sc->sc_flags);
}

void ath9k_set_beaconing_status(struct ath_softc *sc, bool status)
@@ -818,7 +818,7 @@ void ath9k_set_beaconing_status(struct ath_softc *sc, bool status)
struct ath_hw *ah = sc->sc_ah;

if (!ath_has_valid_bslot(sc)) {
- sc->sc_flags &= ~SC_OP_BEACONS;
+ clear_bit(SC_OP_BEACONS, &sc->sc_flags);
return;
}

diff --git a/drivers/net/wireless/ath/ath9k/debug.c b/drivers/net/wireless/ath/ath9k/debug.c
index c134dda..2831258 100644
--- a/drivers/net/wireless/ath/ath9k/debug.c
+++ b/drivers/net/wireless/ath/ath9k/debug.c
@@ -205,10 +205,10 @@ static ssize_t write_file_disable_ani(struct file *file,
common->disable_ani = !!disable_ani;

if (disable_ani) {
- sc->sc_flags &= ~SC_OP_ANI_RUN;
+ clear_bit(SC_OP_ANI_RUN, &sc->sc_flags);
del_timer_sync(&common->ani.timer);
} else {
- sc->sc_flags |= SC_OP_ANI_RUN;
+ set_bit(SC_OP_ANI_RUN, &sc->sc_flags);
ath_start_ani(common);
}

@@ -1321,7 +1321,7 @@ static int open_file_bb_mac_samps(struct inode *inode, struct file *file)
u8 chainmask = (ah->rxchainmask << 3) | ah->rxchainmask;
u8 nread;

- if (sc->sc_flags & SC_OP_INVALID)
+ if (test_bit(SC_OP_INVALID, &sc->sc_flags))
return -EAGAIN;

buf = vmalloc(size);
diff --git a/drivers/net/wireless/ath/ath9k/link.c b/drivers/net/wireless/ath/ath9k/link.c
index 89b38a9..0cc4c70 100644
--- a/drivers/net/wireless/ath/ath9k/link.c
+++ b/drivers/net/wireless/ath/ath9k/link.c
@@ -155,7 +155,7 @@ void ath_start_rx_poll(struct ath_softc *sc, u8 nbeacon)
if (!AR_SREV_9300(sc->sc_ah))
return;

- if (!(sc->sc_flags & SC_OP_PRIM_STA_VIF))
+ if (!test_bit(SC_OP_PRIM_STA_VIF, &sc->sc_flags))
return;

mod_timer(&sc->rx_poll_timer, jiffies + msecs_to_jiffies
@@ -430,7 +430,7 @@ void ath_start_ani(struct ath_common *common)
unsigned long timestamp = jiffies_to_msecs(jiffies);
struct ath_softc *sc = (struct ath_softc *) common->priv;

- if (!(sc->sc_flags & SC_OP_ANI_RUN))
+ if (!test_bit(SC_OP_ANI_RUN, &sc->sc_flags))
return;

if (sc->hw->conf.flags & IEEE80211_CONF_OFFCHANNEL)
diff --git a/drivers/net/wireless/ath/ath9k/main.c b/drivers/net/wireless/ath/ath9k/main.c
index 0471c4b..86bfea9 100644
--- a/drivers/net/wireless/ath/ath9k/main.c
+++ b/drivers/net/wireless/ath/ath9k/main.c
@@ -222,7 +222,7 @@ static bool ath_complete_reset(struct ath_softc *sc, bool start)
ath9k_hw_enable_interrupts(ah);

if (!(sc->hw->conf.flags & IEEE80211_CONF_OFFCHANNEL) && start) {
- if (sc->sc_flags & SC_OP_BEACONS)
+ if (test_bit(SC_OP_BEACONS, &sc->sc_flags))
ath_set_beacon(sc);

ath_restart_work(sc);
@@ -293,7 +293,7 @@ static int ath_set_channel(struct ath_softc *sc, struct ieee80211_hw *hw,
{
int r;

- if (sc->sc_flags & SC_OP_INVALID)
+ if (test_bit(SC_OP_INVALID, &sc->sc_flags))
return -EIO;

r = ath_reset_internal(sc, hchan, false);
@@ -435,7 +435,7 @@ irqreturn_t ath_isr(int irq, void *dev)
* touch anything. Note this can happen early
* on if the IRQ is shared.
*/
- if (sc->sc_flags & SC_OP_INVALID)
+ if (test_bit(SC_OP_INVALID, &sc->sc_flags))
return IRQ_NONE;


@@ -635,7 +635,7 @@ static int ath9k_start(struct ieee80211_hw *hw)

ath_mci_enable(sc);

- sc->sc_flags &= ~SC_OP_INVALID;
+ clear_bit(SC_OP_INVALID, &sc->sc_flags);
sc->sc_ah->is_monitoring = false;

if (!ath_complete_reset(sc, false)) {
@@ -754,7 +754,7 @@ static void ath9k_stop(struct ieee80211_hw *hw)
ath_cancel_work(sc);
del_timer_sync(&sc->rx_poll_timer);

- if (sc->sc_flags & SC_OP_INVALID) {
+ if (test_bit(SC_OP_INVALID, &sc->sc_flags)) {
ath_dbg(common, ANY, "Device not present\n");
mutex_unlock(&sc->mutex);
return;
@@ -811,7 +811,7 @@ static void ath9k_stop(struct ieee80211_hw *hw)

ath9k_ps_restore(sc);

- sc->sc_flags |= SC_OP_INVALID;
+ set_bit(SC_OP_INVALID, &sc->sc_flags);
sc->ps_idle = prev_idle;

mutex_unlock(&sc->mutex);
@@ -915,11 +915,11 @@ static void ath9k_calculate_summary_state(struct ieee80211_hw *hw,
/* Set op-mode & TSF */
if (iter_data.naps > 0) {
ath9k_hw_set_tsfadjust(ah, 1);
- sc->sc_flags |= SC_OP_TSF_RESET;
+ set_bit(SC_OP_TSF_RESET, &sc->sc_flags);
ah->opmode = NL80211_IFTYPE_AP;
} else {
ath9k_hw_set_tsfadjust(ah, 0);
- sc->sc_flags &= ~SC_OP_TSF_RESET;
+ clear_bit(SC_OP_TSF_RESET, &sc->sc_flags);

if (iter_data.nmeshes)
ah->opmode = NL80211_IFTYPE_MESH_POINT;
@@ -950,12 +950,12 @@ static void ath9k_calculate_summary_state(struct ieee80211_hw *hw,
sc->sc_ah->stats.avgbrssi = ATH_RSSI_DUMMY_MARKER;

if (!common->disable_ani) {
- sc->sc_flags |= SC_OP_ANI_RUN;
+ set_bit(SC_OP_ANI_RUN, &sc->sc_flags);
ath_start_ani(common);
}

} else {
- sc->sc_flags &= ~SC_OP_ANI_RUN;
+ clear_bit(SC_OP_ANI_RUN, &sc->sc_flags);
del_timer_sync(&common->ani.timer);
}
}
@@ -1479,11 +1479,11 @@ static void ath9k_bss_iter(void *data, u8 *mac, struct ieee80211_vif *vif)
* Skip iteration if primary station vif's bss info
* was not changed
*/
- if (sc->sc_flags & SC_OP_PRIM_STA_VIF)
+ if (test_bit(SC_OP_PRIM_STA_VIF, &sc->sc_flags))
return;

if (bss_conf->assoc) {
- sc->sc_flags |= SC_OP_PRIM_STA_VIF;
+ set_bit(SC_OP_PRIM_STA_VIF, &sc->sc_flags);
avp->primary_sta_vif = true;
memcpy(common->curbssid, bss_conf->bssid, ETH_ALEN);
common->curaid = bss_conf->aid;
@@ -1504,7 +1504,7 @@ static void ath9k_bss_iter(void *data, u8 *mac, struct ieee80211_vif *vif)
ath_start_rx_poll(sc, 3);

if (!common->disable_ani) {
- sc->sc_flags |= SC_OP_ANI_RUN;
+ set_bit(SC_OP_ANI_RUN, &sc->sc_flags);
ath_start_ani(common);
}

@@ -1524,7 +1524,8 @@ static void ath9k_config_bss(struct ath_softc *sc, struct ieee80211_vif *vif)
if (avp->primary_sta_vif && !bss_conf->assoc) {
ath_dbg(common, CONFIG, "Bss Info DISASSOC %d, bssid %pM\n",
common->curaid, common->curbssid);
- sc->sc_flags &= ~(SC_OP_PRIM_STA_VIF | SC_OP_BEACONS);
+ clear_bit(SC_OP_PRIM_STA_VIF, &sc->sc_flags);
+ clear_bit(SC_OP_BEACONS, &sc->sc_flags);
avp->primary_sta_vif = false;
memset(common->curbssid, 0, ETH_ALEN);
common->curaid = 0;
@@ -1537,10 +1538,9 @@ static void ath9k_config_bss(struct ath_softc *sc, struct ieee80211_vif *vif)
* None of station vifs are associated.
* Clear bssid & aid
*/
- if (!(sc->sc_flags & SC_OP_PRIM_STA_VIF)) {
+ if (!test_bit(SC_OP_PRIM_STA_VIF, &sc->sc_flags)) {
ath9k_hw_write_associd(sc->sc_ah);
- /* Stop ANI */
- sc->sc_flags &= ~SC_OP_ANI_RUN;
+ clear_bit(SC_OP_ANI_RUN, &sc->sc_flags);
del_timer_sync(&common->ani.timer);
del_timer_sync(&sc->rx_poll_timer);
memset(&sc->caldata, 0, sizeof(sc->caldata));
@@ -1578,12 +1578,12 @@ static void ath9k_bss_info_changed(struct ieee80211_hw *hw,
sc->sc_ah->stats.avgbrssi = ATH_RSSI_DUMMY_MARKER;

if (!common->disable_ani) {
- sc->sc_flags |= SC_OP_ANI_RUN;
+ set_bit(SC_OP_ANI_RUN, &sc->sc_flags);
ath_start_ani(common);
}

} else {
- sc->sc_flags &= ~SC_OP_ANI_RUN;
+ clear_bit(SC_OP_ANI_RUN, &sc->sc_flags);
del_timer_sync(&common->ani.timer);
del_timer_sync(&sc->rx_poll_timer);
}
@@ -1595,7 +1595,7 @@ static void ath9k_bss_info_changed(struct ieee80211_hw *hw,
*/
if ((changed & BSS_CHANGED_BEACON_INT) &&
(vif->type == NL80211_IFTYPE_AP))
- sc->sc_flags |= SC_OP_TSF_RESET;
+ set_bit(SC_OP_TSF_RESET, &sc->sc_flags);

/* Configure beaconing (AP, IBSS, MESH) */
if (ath9k_uses_beacons(vif->type) &&
@@ -1787,7 +1787,7 @@ static void ath9k_flush(struct ieee80211_hw *hw, bool drop)
return;
}

- if (sc->sc_flags & SC_OP_INVALID) {
+ if (test_bit(SC_OP_INVALID, &sc->sc_flags)) {
ath_dbg(common, ANY, "Device not present\n");
mutex_unlock(&sc->mutex);
return;
diff --git a/drivers/net/wireless/ath/ath9k/pci.c b/drivers/net/wireless/ath/ath9k/pci.c
index 6ec9f88..aa0e83a 100644
--- a/drivers/net/wireless/ath/ath9k/pci.c
+++ b/drivers/net/wireless/ath/ath9k/pci.c
@@ -251,7 +251,7 @@ static int ath_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
sc->mem = mem;

/* Will be cleared in ath9k_start() */
- sc->sc_flags |= SC_OP_INVALID;
+ set_bit(SC_OP_INVALID, &sc->sc_flags);

ret = request_irq(pdev->irq, ath_isr, IRQF_SHARED, "ath9k", sc);
if (ret) {
diff --git a/drivers/net/wireless/ath/ath9k/recv.c b/drivers/net/wireless/ath/ath9k/recv.c
index b45256e..3ac52c5 100644
--- a/drivers/net/wireless/ath/ath9k/recv.c
+++ b/drivers/net/wireless/ath/ath9k/recv.c
@@ -285,8 +285,8 @@ int ath_rx_init(struct ath_softc *sc, int nbufs)
int error = 0;

spin_lock_init(&sc->sc_pcu_lock);
- sc->sc_flags &= ~SC_OP_RXFLUSH;
spin_lock_init(&sc->rx.rxbuflock);
+ clear_bit(SC_OP_RXFLUSH, &sc->sc_flags);

common->rx_bufsize = IEEE80211_MAX_MPDU_LEN / 2 +
sc->sc_ah->caps.rx_status_len;
@@ -498,11 +498,11 @@ bool ath_stoprecv(struct ath_softc *sc)

void ath_flushrecv(struct ath_softc *sc)
{
- sc->sc_flags |= SC_OP_RXFLUSH;
+ set_bit(SC_OP_RXFLUSH, &sc->sc_flags);
if (sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_EDMA)
ath_rx_tasklet(sc, 1, true);
ath_rx_tasklet(sc, 1, false);
- sc->sc_flags &= ~SC_OP_RXFLUSH;
+ clear_bit(SC_OP_RXFLUSH, &sc->sc_flags);
}

static bool ath_beacon_dtim_pending_cab(struct sk_buff *skb)
@@ -1063,7 +1063,7 @@ int ath_rx_tasklet(struct ath_softc *sc, int flush, bool hp)

do {
/* If handling rx interrupt and flush is in progress => exit */
- if ((sc->sc_flags & SC_OP_RXFLUSH) && (flush == 0))
+ if (test_bit(SC_OP_RXFLUSH, &sc->sc_flags) && (flush == 0))
break;

memset(&rs, 0, sizeof(rs));
@@ -1108,7 +1108,7 @@ int ath_rx_tasklet(struct ath_softc *sc, int flush, bool hp)
* If we're asked to flush receive queue, directly
* chain it back at the queue without processing it.
*/
- if (sc->sc_flags & SC_OP_RXFLUSH) {
+ if (test_bit(SC_OP_RXFLUSH, &sc->sc_flags)) {
RX_STAT_INC(rx_drop_rxflush);
goto requeue_drop_frag;
}
diff --git a/drivers/net/wireless/ath/ath9k/xmit.c b/drivers/net/wireless/ath/ath9k/xmit.c
index 6619a39..bb74780 100644
--- a/drivers/net/wireless/ath/ath9k/xmit.c
+++ b/drivers/net/wireless/ath/ath9k/xmit.c
@@ -1536,7 +1536,7 @@ bool ath_drain_all_txq(struct ath_softc *sc, bool retry_tx)
int i;
u32 npend = 0;

- if (sc->sc_flags & SC_OP_INVALID)
+ if (test_bit(SC_OP_INVALID, &sc->sc_flags))
return true;

ath9k_hw_abort_tx_dma(ah);
--
1.7.10.3