* [ath9k-devel] [PATCH 0/2] ath9k: kill of ACCESS_ONCE() in MAC drivers
@ 2016-12-27 18:49 Mark Rutland
2016-12-27 18:49 ` [ath9k-devel] [PATCH 1/2] ath9k: ar9002_mac: kill off ACCESS_ONCE() Mark Rutland
2016-12-27 18:49 ` [ath9k-devel] [PATCH 2/2] ath9k: ar9003_mac: " Mark Rutland
0 siblings, 2 replies; 4+ messages in thread
From: Mark Rutland @ 2016-12-27 18:49 UTC (permalink / raw)
To: ath9k-devel
For several reasons, it would be beneficial to kill off ACCESS_ONCE()
tree-wide, in favour of {READ,WRITE}_ONCE(). These work with aggregate
types, more obviously document their intended behaviour, and are
necessary for tools like KTSAN to work correctly (as otherwise reads and
writes cannot be instrumented separately).
While it's possible to script a tree-wide conversion using Coccinelle,
some cases such as the ath9k MAC drivers require some manual
intervention to ensure that the resulting code remains legible. This
series moves the ath9k MAC drivers over to {READ,WRITE}_ONCE(). In both
cases this is functionally equivalent to the below Coccinelle script
being applied, though the existing formatting is retained.
----
virtual patch
@ depends on patch @
expression E1, E2;
@@
- ACCESS_ONCE(E1) = E2
+ WRITE_ONCE(E1, E2)
@ depends on patch @
expression E;
@@
- ACCESS_ONCE(E)
+ READ_ONCE(E)
----
Thanks,
Mark.
Mark Rutland (2):
ath9k: ar9002_mac: kill off ACCESS_ONCE()
ath9k: ar9003_mac: kill off ACCESS_ONCE()
drivers/net/wireless/ath/ath9k/ar9002_mac.c | 64 ++++++++++----------
drivers/net/wireless/ath/ath9k/ar9003_mac.c | 92 ++++++++++++++---------------
2 files changed, 78 insertions(+), 78 deletions(-)
--
2.7.4
^ permalink raw reply [flat|nested] 4+ messages in thread
* [ath9k-devel] [PATCH 1/2] ath9k: ar9002_mac: kill off ACCESS_ONCE()
2016-12-27 18:49 [ath9k-devel] [PATCH 0/2] ath9k: kill of ACCESS_ONCE() in MAC drivers Mark Rutland
@ 2016-12-27 18:49 ` Mark Rutland
2017-01-12 11:00 ` [ath9k-devel] [1/2] " Kalle Valo
2016-12-27 18:49 ` [ath9k-devel] [PATCH 2/2] ath9k: ar9003_mac: " Mark Rutland
1 sibling, 1 reply; 4+ messages in thread
From: Mark Rutland @ 2016-12-27 18:49 UTC (permalink / raw)
To: ath9k-devel
For several reasons, it is desirable to use {READ,WRITE}_ONCE() in
preference to ACCESS_ONCE(), and new code is expected to use one of the
former. So far, there's been no reason to change most existing uses of
ACCESS_ONCE(), as these aren't currently harmful.
However, for some new features (e.g. KTSAN / Kernel Thread Sanitizer),
it is necessary to instrument reads and writes separately, which is not
possible with ACCESS_ONCE(). This distinction is critical to correct
operation.
It's possible to transform the bulk of kernel code using the Coccinelle
script below. However, for some files (including the ath9k ar9002 mac
driver), this mangles the formatting. As a preparatory step, this patch
converts the driver to use {READ,WRITE}_ONCE() without said mangling.
----
virtual patch
@ depends on patch @
expression E1, E2;
@@
- ACCESS_ONCE(E1) = E2
+ WRITE_ONCE(E1, E2)
@ depends on patch @
expression E;
@@
- ACCESS_ONCE(E)
+ READ_ONCE(E)
----
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: ath9k-devel at qca.qualcomm.com
Cc: Kalle Valo <kvalo@codeaurora.org>
Cc: linux-wireless at vger.kernel.org
Cc: ath9k-devel at lists.ath9k.org
Cc: netdev at vger.kernel.org
---
drivers/net/wireless/ath/ath9k/ar9002_mac.c | 64 ++++++++++++++---------------
1 file changed, 32 insertions(+), 32 deletions(-)
diff --git a/drivers/net/wireless/ath/ath9k/ar9002_mac.c b/drivers/net/wireless/ath/ath9k/ar9002_mac.c
index f816909..4b3c9b1 100644
--- a/drivers/net/wireless/ath/ath9k/ar9002_mac.c
+++ b/drivers/net/wireless/ath/ath9k/ar9002_mac.c
@@ -220,8 +220,8 @@ ar9002_set_txdesc(struct ath_hw *ah, void *ds, struct ath_tx_info *i)
ads->ds_txstatus6 = ads->ds_txstatus7 = 0;
ads->ds_txstatus8 = ads->ds_txstatus9 = 0;
- ACCESS_ONCE(ads->ds_link) = i->link;
- ACCESS_ONCE(ads->ds_data) = i->buf_addr[0];
+ WRITE_ONCE(ads->ds_link, i->link);
+ WRITE_ONCE(ads->ds_data, i->buf_addr[0]);
ctl1 = i->buf_len[0] | (i->is_last ? 0 : AR_TxMore);
ctl6 = SM(i->keytype, AR_EncrType);
@@ -235,26 +235,26 @@ ar9002_set_txdesc(struct ath_hw *ah, void *ds, struct ath_tx_info *i)
if ((i->is_first || i->is_last) &&
i->aggr != AGGR_BUF_MIDDLE && i->aggr != AGGR_BUF_LAST) {
- ACCESS_ONCE(ads->ds_ctl2) = set11nTries(i->rates, 0)
+ WRITE_ONCE(ads->ds_ctl2, set11nTries(i->rates, 0)
| set11nTries(i->rates, 1)
| set11nTries(i->rates, 2)
| set11nTries(i->rates, 3)
| (i->dur_update ? AR_DurUpdateEna : 0)
- | SM(0, AR_BurstDur);
+ | SM(0, AR_BurstDur));
- ACCESS_ONCE(ads->ds_ctl3) = set11nRate(i->rates, 0)
+ WRITE_ONCE(ads->ds_ctl3, set11nRate(i->rates, 0)
| set11nRate(i->rates, 1)
| set11nRate(i->rates, 2)
- | set11nRate(i->rates, 3);
+ | set11nRate(i->rates, 3));
} else {
- ACCESS_ONCE(ads->ds_ctl2) = 0;
- ACCESS_ONCE(ads->ds_ctl3) = 0;
+ WRITE_ONCE(ads->ds_ctl2, 0);
+ WRITE_ONCE(ads->ds_ctl3, 0);
}
if (!i->is_first) {
- ACCESS_ONCE(ads->ds_ctl0) = 0;
- ACCESS_ONCE(ads->ds_ctl1) = ctl1;
- ACCESS_ONCE(ads->ds_ctl6) = ctl6;
+ WRITE_ONCE(ads->ds_ctl0, 0);
+ WRITE_ONCE(ads->ds_ctl1, ctl1);
+ WRITE_ONCE(ads->ds_ctl6, ctl6);
return;
}
@@ -279,7 +279,7 @@ ar9002_set_txdesc(struct ath_hw *ah, void *ds, struct ath_tx_info *i)
break;
}
- ACCESS_ONCE(ads->ds_ctl0) = (i->pkt_len & AR_FrameLen)
+ WRITE_ONCE(ads->ds_ctl0, (i->pkt_len & AR_FrameLen)
| (i->flags & ATH9K_TXDESC_VMF ? AR_VirtMoreFrag : 0)
| SM(i->txpower[0], AR_XmitPower0)
| (i->flags & ATH9K_TXDESC_VEOL ? AR_VEOL : 0)
@@ -287,29 +287,29 @@ ar9002_set_txdesc(struct ath_hw *ah, void *ds, struct ath_tx_info *i)
| (i->keyix != ATH9K_TXKEYIX_INVALID ? AR_DestIdxValid : 0)
| (i->flags & ATH9K_TXDESC_CLRDMASK ? AR_ClrDestMask : 0)
| (i->flags & ATH9K_TXDESC_RTSENA ? AR_RTSEnable :
- (i->flags & ATH9K_TXDESC_CTSENA ? AR_CTSEnable : 0));
+ (i->flags & ATH9K_TXDESC_CTSENA ? AR_CTSEnable : 0)));
- ACCESS_ONCE(ads->ds_ctl1) = ctl1;
- ACCESS_ONCE(ads->ds_ctl6) = ctl6;
+ WRITE_ONCE(ads->ds_ctl1, ctl1);
+ WRITE_ONCE(ads->ds_ctl6, ctl6);
if (i->aggr == AGGR_BUF_MIDDLE || i->aggr == AGGR_BUF_LAST)
return;
- ACCESS_ONCE(ads->ds_ctl4) = set11nPktDurRTSCTS(i->rates, 0)
- | set11nPktDurRTSCTS(i->rates, 1);
+ WRITE_ONCE(ads->ds_ctl4, set11nPktDurRTSCTS(i->rates, 0)
+ | set11nPktDurRTSCTS(i->rates, 1));
- ACCESS_ONCE(ads->ds_ctl5) = set11nPktDurRTSCTS(i->rates, 2)
- | set11nPktDurRTSCTS(i->rates, 3);
+ WRITE_ONCE(ads->ds_ctl5, set11nPktDurRTSCTS(i->rates, 2)
+ | set11nPktDurRTSCTS(i->rates, 3));
- ACCESS_ONCE(ads->ds_ctl7) = set11nRateFlags(i->rates, 0)
+ WRITE_ONCE(ads->ds_ctl7, set11nRateFlags(i->rates, 0)
| set11nRateFlags(i->rates, 1)
| set11nRateFlags(i->rates, 2)
| set11nRateFlags(i->rates, 3)
- | SM(i->rtscts_rate, AR_RTSCTSRate);
+ | SM(i->rtscts_rate, AR_RTSCTSRate));
- ACCESS_ONCE(ads->ds_ctl9) = SM(i->txpower[1], AR_XmitPower1);
- ACCESS_ONCE(ads->ds_ctl10) = SM(i->txpower[2], AR_XmitPower2);
- ACCESS_ONCE(ads->ds_ctl11) = SM(i->txpower[3], AR_XmitPower3);
+ WRITE_ONCE(ads->ds_ctl9, SM(i->txpower[1], AR_XmitPower1));
+ WRITE_ONCE(ads->ds_ctl10, SM(i->txpower[2], AR_XmitPower2));
+ WRITE_ONCE(ads->ds_ctl11, SM(i->txpower[3], AR_XmitPower3));
}
static int ar9002_hw_proc_txdesc(struct ath_hw *ah, void *ds,
@@ -318,7 +318,7 @@ static int ar9002_hw_proc_txdesc(struct ath_hw *ah, void *ds,
struct ar5416_desc *ads = AR5416DESC(ds);
u32 status;
- status = ACCESS_ONCE(ads->ds_txstatus9);
+ status = READ_ONCE(ads->ds_txstatus9);
if ((status & AR_TxDone) == 0)
return -EINPROGRESS;
@@ -332,7 +332,7 @@ static int ar9002_hw_proc_txdesc(struct ath_hw *ah, void *ds,
ts->ts_rateindex = MS(status, AR_FinalTxIdx);
ts->ts_seqnum = MS(status, AR_SeqNum);
- status = ACCESS_ONCE(ads->ds_txstatus0);
+ status = READ_ONCE(ads->ds_txstatus0);
ts->ts_rssi_ctl0 = MS(status, AR_TxRSSIAnt00);
ts->ts_rssi_ctl1 = MS(status, AR_TxRSSIAnt01);
ts->ts_rssi_ctl2 = MS(status, AR_TxRSSIAnt02);
@@ -342,7 +342,7 @@ static int ar9002_hw_proc_txdesc(struct ath_hw *ah, void *ds,
ts->ba_high = ads->AR_BaBitmapHigh;
}
- status = ACCESS_ONCE(ads->ds_txstatus1);
+ status = READ_ONCE(ads->ds_txstatus1);
if (status & AR_FrmXmitOK)
ts->ts_status |= ATH9K_TX_ACKED;
else {
@@ -371,7 +371,7 @@ static int ar9002_hw_proc_txdesc(struct ath_hw *ah, void *ds,
ts->ts_longretry = MS(status, AR_DataFailCnt);
ts->ts_virtcol = MS(status, AR_VirtRetryCnt);
- status = ACCESS_ONCE(ads->ds_txstatus5);
+ status = READ_ONCE(ads->ds_txstatus5);
ts->ts_rssi = MS(status, AR_TxRSSICombined);
ts->ts_rssi_ext0 = MS(status, AR_TxRSSIAnt10);
ts->ts_rssi_ext1 = MS(status, AR_TxRSSIAnt11);
@@ -390,13 +390,13 @@ static int ar9002_hw_get_duration(struct ath_hw *ah, const void *ds, int index)
switch (index) {
case 0:
- return MS(ACCESS_ONCE(ads->ds_ctl4), AR_PacketDur0);
+ return MS(READ_ONCE(ads->ds_ctl4), AR_PacketDur0);
case 1:
- return MS(ACCESS_ONCE(ads->ds_ctl4), AR_PacketDur1);
+ return MS(READ_ONCE(ads->ds_ctl4), AR_PacketDur1);
case 2:
- return MS(ACCESS_ONCE(ads->ds_ctl5), AR_PacketDur2);
+ return MS(READ_ONCE(ads->ds_ctl5), AR_PacketDur2);
case 3:
- return MS(ACCESS_ONCE(ads->ds_ctl5), AR_PacketDur3);
+ return MS(READ_ONCE(ads->ds_ctl5), AR_PacketDur3);
default:
return -1;
}
--
2.7.4
^ permalink raw reply related [flat|nested] 4+ messages in thread
* [ath9k-devel] [PATCH 2/2] ath9k: ar9003_mac: kill off ACCESS_ONCE()
2016-12-27 18:49 [ath9k-devel] [PATCH 0/2] ath9k: kill of ACCESS_ONCE() in MAC drivers Mark Rutland
2016-12-27 18:49 ` [ath9k-devel] [PATCH 1/2] ath9k: ar9002_mac: kill off ACCESS_ONCE() Mark Rutland
@ 2016-12-27 18:49 ` Mark Rutland
1 sibling, 0 replies; 4+ messages in thread
From: Mark Rutland @ 2016-12-27 18:49 UTC (permalink / raw)
To: ath9k-devel
For several reasons, it is desirable to use {READ,WRITE}_ONCE() in
preference to ACCESS_ONCE(), and new code is expected to use one of the
former. So far, there's been no reason to change most existing uses of
ACCESS_ONCE(), as these aren't currently harmful.
However, for some new features (e.g. KTSAN / Kernel Thread Sanitizer),
it is necessary to instrument reads and writes separately, which is not
possible with ACCESS_ONCE(). This distinction is critical to correct
operation.
It's possible to transform the bulk of kernel code using the Coccinelle
script below. However, for some files (including the ath9k ar9003 mac
driver), this mangles the formatting. As a preparatory step, this patch
converts the driver to use {READ,WRITE}_ONCE() without said mangling.
----
virtual patch
@ depends on patch @
expression E1, E2;
@@
- ACCESS_ONCE(E1) = E2
+ WRITE_ONCE(E1, E2)
@ depends on patch @
expression E;
@@
- ACCESS_ONCE(E)
+ READ_ONCE(E)
----
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: ath9k-devel at qca.qualcomm.com
Cc: Kalle Valo <kvalo@codeaurora.org>
Cc: linux-wireless at vger.kernel.org
Cc: ath9k-devel at lists.ath9k.org
Cc: netdev at vger.kernel.org
---
drivers/net/wireless/ath/ath9k/ar9003_mac.c | 92 ++++++++++++++---------------
1 file changed, 46 insertions(+), 46 deletions(-)
diff --git a/drivers/net/wireless/ath/ath9k/ar9003_mac.c b/drivers/net/wireless/ath/ath9k/ar9003_mac.c
index da84b70..cc5bb0a 100644
--- a/drivers/net/wireless/ath/ath9k/ar9003_mac.c
+++ b/drivers/net/wireless/ath/ath9k/ar9003_mac.c
@@ -39,47 +39,47 @@ ar9003_set_txdesc(struct ath_hw *ah, void *ds, struct ath_tx_info *i)
(i->qcu << AR_TxQcuNum_S) | desc_len;
checksum += val;
- ACCESS_ONCE(ads->info) = val;
+ WRITE_ONCE(ads->info, val);
checksum += i->link;
- ACCESS_ONCE(ads->link) = i->link;
+ WRITE_ONCE(ads->link, i->link);
checksum += i->buf_addr[0];
- ACCESS_ONCE(ads->data0) = i->buf_addr[0];
+ WRITE_ONCE(ads->data0, i->buf_addr[0]);
checksum += i->buf_addr[1];
- ACCESS_ONCE(ads->data1) = i->buf_addr[1];
+ WRITE_ONCE(ads->data1, i->buf_addr[1]);
checksum += i->buf_addr[2];
- ACCESS_ONCE(ads->data2) = i->buf_addr[2];
+ WRITE_ONCE(ads->data2, i->buf_addr[2]);
checksum += i->buf_addr[3];
- ACCESS_ONCE(ads->data3) = i->buf_addr[3];
+ WRITE_ONCE(ads->data3, i->buf_addr[3]);
checksum += (val = (i->buf_len[0] << AR_BufLen_S) & AR_BufLen);
- ACCESS_ONCE(ads->ctl3) = val;
+ WRITE_ONCE(ads->ctl3, val);
checksum += (val = (i->buf_len[1] << AR_BufLen_S) & AR_BufLen);
- ACCESS_ONCE(ads->ctl5) = val;
+ WRITE_ONCE(ads->ctl5, val);
checksum += (val = (i->buf_len[2] << AR_BufLen_S) & AR_BufLen);
- ACCESS_ONCE(ads->ctl7) = val;
+ WRITE_ONCE(ads->ctl7, val);
checksum += (val = (i->buf_len[3] << AR_BufLen_S) & AR_BufLen);
- ACCESS_ONCE(ads->ctl9) = val;
+ WRITE_ONCE(ads->ctl9, val);
checksum = (u16) (((checksum & 0xffff) + (checksum >> 16)) & 0xffff);
- ACCESS_ONCE(ads->ctl10) = checksum;
+ WRITE_ONCE(ads->ctl10, checksum);
if (i->is_first || i->is_last) {
- ACCESS_ONCE(ads->ctl13) = set11nTries(i->rates, 0)
+ WRITE_ONCE(ads->ctl13, set11nTries(i->rates, 0)
| set11nTries(i->rates, 1)
| set11nTries(i->rates, 2)
| set11nTries(i->rates, 3)
| (i->dur_update ? AR_DurUpdateEna : 0)
- | SM(0, AR_BurstDur);
+ | SM(0, AR_BurstDur));
- ACCESS_ONCE(ads->ctl14) = set11nRate(i->rates, 0)
+ WRITE_ONCE(ads->ctl14, set11nRate(i->rates, 0)
| set11nRate(i->rates, 1)
| set11nRate(i->rates, 2)
- | set11nRate(i->rates, 3);
+ | set11nRate(i->rates, 3));
} else {
- ACCESS_ONCE(ads->ctl13) = 0;
- ACCESS_ONCE(ads->ctl14) = 0;
+ WRITE_ONCE(ads->ctl13, 0);
+ WRITE_ONCE(ads->ctl14, 0);
}
ads->ctl20 = 0;
@@ -89,17 +89,17 @@ ar9003_set_txdesc(struct ath_hw *ah, void *ds, struct ath_tx_info *i)
ctl17 = SM(i->keytype, AR_EncrType);
if (!i->is_first) {
- ACCESS_ONCE(ads->ctl11) = 0;
- ACCESS_ONCE(ads->ctl12) = i->is_last ? 0 : AR_TxMore;
- ACCESS_ONCE(ads->ctl15) = 0;
- ACCESS_ONCE(ads->ctl16) = 0;
- ACCESS_ONCE(ads->ctl17) = ctl17;
- ACCESS_ONCE(ads->ctl18) = 0;
- ACCESS_ONCE(ads->ctl19) = 0;
+ WRITE_ONCE(ads->ctl11, 0);
+ WRITE_ONCE(ads->ctl12, i->is_last ? 0 : AR_TxMore);
+ WRITE_ONCE(ads->ctl15, 0);
+ WRITE_ONCE(ads->ctl16, 0);
+ WRITE_ONCE(ads->ctl17, ctl17);
+ WRITE_ONCE(ads->ctl18, 0);
+ WRITE_ONCE(ads->ctl19, 0);
return;
}
- ACCESS_ONCE(ads->ctl11) = (i->pkt_len & AR_FrameLen)
+ WRITE_ONCE(ads->ctl11, (i->pkt_len & AR_FrameLen)
| (i->flags & ATH9K_TXDESC_VMF ? AR_VirtMoreFrag : 0)
| SM(i->txpower[0], AR_XmitPower0)
| (i->flags & ATH9K_TXDESC_VEOL ? AR_VEOL : 0)
@@ -107,7 +107,7 @@ ar9003_set_txdesc(struct ath_hw *ah, void *ds, struct ath_tx_info *i)
| (i->flags & ATH9K_TXDESC_LOWRXCHAIN ? AR_LowRxChain : 0)
| (i->flags & ATH9K_TXDESC_CLRDMASK ? AR_ClrDestMask : 0)
| (i->flags & ATH9K_TXDESC_RTSENA ? AR_RTSEnable :
- (i->flags & ATH9K_TXDESC_CTSENA ? AR_CTSEnable : 0));
+ (i->flags & ATH9K_TXDESC_CTSENA ? AR_CTSEnable : 0)));
ctl12 = (i->keyix != ATH9K_TXKEYIX_INVALID ?
SM(i->keyix, AR_DestIdx) : 0)
@@ -135,26 +135,26 @@ ar9003_set_txdesc(struct ath_hw *ah, void *ds, struct ath_tx_info *i)
val = (i->flags & ATH9K_TXDESC_PAPRD) >> ATH9K_TXDESC_PAPRD_S;
ctl12 |= SM(val, AR_PAPRDChainMask);
- ACCESS_ONCE(ads->ctl12) = ctl12;
- ACCESS_ONCE(ads->ctl17) = ctl17;
+ WRITE_ONCE(ads->ctl12, ctl12);
+ WRITE_ONCE(ads->ctl17, ctl17);
- ACCESS_ONCE(ads->ctl15) = set11nPktDurRTSCTS(i->rates, 0)
- | set11nPktDurRTSCTS(i->rates, 1);
+ WRITE_ONCE(ads->ctl15, set11nPktDurRTSCTS(i->rates, 0)
+ | set11nPktDurRTSCTS(i->rates, 1));
- ACCESS_ONCE(ads->ctl16) = set11nPktDurRTSCTS(i->rates, 2)
- | set11nPktDurRTSCTS(i->rates, 3);
+ WRITE_ONCE(ads->ctl16, set11nPktDurRTSCTS(i->rates, 2)
+ | set11nPktDurRTSCTS(i->rates, 3));
- ACCESS_ONCE(ads->ctl18) = set11nRateFlags(i->rates, 0)
+ WRITE_ONCE(ads->ctl18, set11nRateFlags(i->rates, 0)
| set11nRateFlags(i->rates, 1)
| set11nRateFlags(i->rates, 2)
| set11nRateFlags(i->rates, 3)
- | SM(i->rtscts_rate, AR_RTSCTSRate);
+ | SM(i->rtscts_rate, AR_RTSCTSRate));
- ACCESS_ONCE(ads->ctl19) = AR_Not_Sounding;
+ WRITE_ONCE(ads->ctl19, AR_Not_Sounding);
- ACCESS_ONCE(ads->ctl20) = SM(i->txpower[1], AR_XmitPower1);
- ACCESS_ONCE(ads->ctl21) = SM(i->txpower[2], AR_XmitPower2);
- ACCESS_ONCE(ads->ctl22) = SM(i->txpower[3], AR_XmitPower3);
+ WRITE_ONCE(ads->ctl20, SM(i->txpower[1], AR_XmitPower1));
+ WRITE_ONCE(ads->ctl21, SM(i->txpower[2], AR_XmitPower2));
+ WRITE_ONCE(ads->ctl22, SM(i->txpower[3], AR_XmitPower3));
}
static u16 ar9003_calc_ptr_chksum(struct ar9003_txc *ads)
@@ -359,7 +359,7 @@ static int ar9003_hw_proc_txdesc(struct ath_hw *ah, void *ds,
ads = &ah->ts_ring[ah->ts_tail];
- status = ACCESS_ONCE(ads->status8);
+ status = READ_ONCE(ads->status8);
if ((status & AR_TxDone) == 0)
return -EINPROGRESS;
@@ -385,7 +385,7 @@ static int ar9003_hw_proc_txdesc(struct ath_hw *ah, void *ds,
if (status & AR_TxOpExceeded)
ts->ts_status |= ATH9K_TXERR_XTXOP;
- status = ACCESS_ONCE(ads->status2);
+ status = READ_ONCE(ads->status2);
ts->ts_rssi_ctl0 = MS(status, AR_TxRSSIAnt00);
ts->ts_rssi_ctl1 = MS(status, AR_TxRSSIAnt01);
ts->ts_rssi_ctl2 = MS(status, AR_TxRSSIAnt02);
@@ -395,7 +395,7 @@ static int ar9003_hw_proc_txdesc(struct ath_hw *ah, void *ds,
ts->ba_high = ads->status6;
}
- status = ACCESS_ONCE(ads->status3);
+ status = READ_ONCE(ads->status3);
if (status & AR_ExcessiveRetries)
ts->ts_status |= ATH9K_TXERR_XRETRY;
if (status & AR_Filtered)
@@ -420,7 +420,7 @@ static int ar9003_hw_proc_txdesc(struct ath_hw *ah, void *ds,
ts->ts_longretry = MS(status, AR_DataFailCnt);
ts->ts_virtcol = MS(status, AR_VirtRetryCnt);
- status = ACCESS_ONCE(ads->status7);
+ status = READ_ONCE(ads->status7);
ts->ts_rssi = MS(status, AR_TxRSSICombined);
ts->ts_rssi_ext0 = MS(status, AR_TxRSSIAnt10);
ts->ts_rssi_ext1 = MS(status, AR_TxRSSIAnt11);
@@ -437,13 +437,13 @@ static int ar9003_hw_get_duration(struct ath_hw *ah, const void *ds, int index)
switch (index) {
case 0:
- return MS(ACCESS_ONCE(adc->ctl15), AR_PacketDur0);
+ return MS(READ_ONCE(adc->ctl15), AR_PacketDur0);
case 1:
- return MS(ACCESS_ONCE(adc->ctl15), AR_PacketDur1);
+ return MS(READ_ONCE(adc->ctl15), AR_PacketDur1);
case 2:
- return MS(ACCESS_ONCE(adc->ctl16), AR_PacketDur2);
+ return MS(READ_ONCE(adc->ctl16), AR_PacketDur2);
case 3:
- return MS(ACCESS_ONCE(adc->ctl16), AR_PacketDur3);
+ return MS(READ_ONCE(adc->ctl16), AR_PacketDur3);
default:
return 0;
}
--
2.7.4
^ permalink raw reply related [flat|nested] 4+ messages in thread
* [ath9k-devel] [1/2] ath9k: ar9002_mac: kill off ACCESS_ONCE()
2016-12-27 18:49 ` [ath9k-devel] [PATCH 1/2] ath9k: ar9002_mac: kill off ACCESS_ONCE() Mark Rutland
@ 2017-01-12 11:00 ` Kalle Valo
0 siblings, 0 replies; 4+ messages in thread
From: Kalle Valo @ 2017-01-12 11:00 UTC (permalink / raw)
To: ath9k-devel
Mark Rutland <mark.rutland@arm.com> wrote:
> For several reasons, it is desirable to use {READ,WRITE}_ONCE() in
> preference to ACCESS_ONCE(), and new code is expected to use one of the
> former. So far, there's been no reason to change most existing uses of
> ACCESS_ONCE(), as these aren't currently harmful.
>
> However, for some new features (e.g. KTSAN / Kernel Thread Sanitizer),
> it is necessary to instrument reads and writes separately, which is not
> possible with ACCESS_ONCE(). This distinction is critical to correct
> operation.
>
> It's possible to transform the bulk of kernel code using the Coccinelle
> script below. However, for some files (including the ath9k ar9002 mac
> driver), this mangles the formatting. As a preparatory step, this patch
> converts the driver to use {READ,WRITE}_ONCE() without said mangling.
>
> ----
> virtual patch
>
> @ depends on patch @
> expression E1, E2;
> @@
>
> - ACCESS_ONCE(E1) = E2
> + WRITE_ONCE(E1, E2)
>
> @ depends on patch @
> expression E;
> @@
>
> - ACCESS_ONCE(E)
> + READ_ONCE(E)
> ----
>
> Signed-off-by: Mark Rutland <mark.rutland@arm.com>
> Cc: ath9k-devel at qca.qualcomm.com
> Cc: Kalle Valo <kvalo@codeaurora.org>
> Cc: linux-wireless at vger.kernel.org
> Cc: ath9k-devel at lists.ath9k.org
> Cc: netdev at vger.kernel.org
2 patches applied to ath-next branch of ath.git, thanks.
d5a3a76a9cb8 ath9k: ar9002_mac: kill off ACCESS_ONCE()
50f3818196f5 ath9k: ar9003_mac: kill off ACCESS_ONCE()
--
https://patchwork.kernel.org/patch/9489799/
Documentation about submitting wireless patches and checking status
from patchwork:
https://wireless.wiki.kernel.org/en/developers/documentation/submittingpatches
^ permalink raw reply [flat|nested] 4+ messages in thread
end of thread, other threads:[~2017-01-12 11:00 UTC | newest]
Thread overview: 4+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2016-12-27 18:49 [ath9k-devel] [PATCH 0/2] ath9k: kill of ACCESS_ONCE() in MAC drivers Mark Rutland
2016-12-27 18:49 ` [ath9k-devel] [PATCH 1/2] ath9k: ar9002_mac: kill off ACCESS_ONCE() Mark Rutland
2017-01-12 11:00 ` [ath9k-devel] [1/2] " Kalle Valo
2016-12-27 18:49 ` [ath9k-devel] [PATCH 2/2] ath9k: ar9003_mac: " Mark Rutland
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).