From: Arnd Bergmann <[email protected]>
A previous cleanup patch accidentally broke some conditional
expressions by replacing the safe "do {} while (0)" constructs
with empty macros. gcc points this out when extra warnings
are enabled:
drivers/net/wireless/ath/ath9k/hif_usb.c: In function 'ath9k_skb_queue_complete':
drivers/net/wireless/ath/ath9k/hif_usb.c:251:57: error: suggest braces around empty body in an 'else' statement [-Werror=empty-body]
251 | TX_STAT_INC(hif_dev, skb_failed);
Make both sets of macros proper expressions again.
Fixes: d7fc76039b74 ("ath9k: htc: clean up statistics macros")
Signed-off-by: Arnd Bergmann <[email protected]>
---
drivers/net/wireless/ath/ath9k/htc.h | 14 +++++++-------
1 file changed, 7 insertions(+), 7 deletions(-)
diff --git a/drivers/net/wireless/ath/ath9k/htc.h b/drivers/net/wireless/ath/ath9k/htc.h
index 30f0765fb9fd..237f4ec2cffd 100644
--- a/drivers/net/wireless/ath/ath9k/htc.h
+++ b/drivers/net/wireless/ath/ath9k/htc.h
@@ -327,9 +327,9 @@ static inline struct ath9k_htc_tx_ctl *HTC_SKB_CB(struct sk_buff *skb)
}
#ifdef CONFIG_ATH9K_HTC_DEBUGFS
-#define __STAT_SAFE(hif_dev, expr) ((hif_dev)->htc_handle->drv_priv ? (expr) : 0)
-#define CAB_STAT_INC(priv) ((priv)->debug.tx_stats.cab_queued++)
-#define TX_QSTAT_INC(priv, q) ((priv)->debug.tx_stats.queue_stats[q]++)
+#define __STAT_SAFE(hif_dev, expr) do { ((hif_dev)->htc_handle->drv_priv ? (expr) : 0); } while (0)
+#define CAB_STAT_INC(priv) do { ((priv)->debug.tx_stats.cab_queued++); } while (0)
+#define TX_QSTAT_INC(priv, q) do { ((priv)->debug.tx_stats.queue_stats[q]++); } while (0)
#define TX_STAT_INC(hif_dev, c) \
__STAT_SAFE((hif_dev), (hif_dev)->htc_handle->drv_priv->debug.tx_stats.c++)
@@ -378,10 +378,10 @@ void ath9k_htc_get_et_stats(struct ieee80211_hw *hw,
struct ethtool_stats *stats, u64 *data);
#else
-#define TX_STAT_INC(hif_dev, c)
-#define TX_STAT_ADD(hif_dev, c, a)
-#define RX_STAT_INC(hif_dev, c)
-#define RX_STAT_ADD(hif_dev, c, a)
+#define TX_STAT_INC(hif_dev, c) do { } while (0)
+#define TX_STAT_ADD(hif_dev, c, a) do { } while (0)
+#define RX_STAT_INC(hif_dev, c) do { } while (0)
+#define RX_STAT_ADD(hif_dev, c, a) do { } while (0)
#define CAB_STAT_INC(priv)
#define TX_QSTAT_INC(priv, c)
--
2.35.1
Arnd Bergmann <[email protected]> writes:
> From: Arnd Bergmann <[email protected]>
>
> A previous cleanup patch accidentally broke some conditional
> expressions by replacing the safe "do {} while (0)" constructs
> with empty macros. gcc points this out when extra warnings
> are enabled:
>
> drivers/net/wireless/ath/ath9k/hif_usb.c: In function 'ath9k_skb_queue_complete':
> drivers/net/wireless/ath/ath9k/hif_usb.c:251:57: error: suggest braces around empty body in an 'else' statement [-Werror=empty-body]
> 251 | TX_STAT_INC(hif_dev, skb_failed);
>
> Make both sets of macros proper expressions again.
>
> Fixes: d7fc76039b74 ("ath9k: htc: clean up statistics macros")
> Signed-off-by: Arnd Bergmann <[email protected]>
> ---
> drivers/net/wireless/ath/ath9k/htc.h | 14 +++++++-------
> 1 file changed, 7 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/net/wireless/ath/ath9k/htc.h b/drivers/net/wireless/ath/ath9k/htc.h
> index 30f0765fb9fd..237f4ec2cffd 100644
> --- a/drivers/net/wireless/ath/ath9k/htc.h
> +++ b/drivers/net/wireless/ath/ath9k/htc.h
> @@ -327,9 +327,9 @@ static inline struct ath9k_htc_tx_ctl *HTC_SKB_CB(struct sk_buff *skb)
> }
>
> #ifdef CONFIG_ATH9K_HTC_DEBUGFS
> -#define __STAT_SAFE(hif_dev, expr) ((hif_dev)->htc_handle->drv_priv ? (expr) : 0)
> -#define CAB_STAT_INC(priv) ((priv)->debug.tx_stats.cab_queued++)
> -#define TX_QSTAT_INC(priv, q) ((priv)->debug.tx_stats.queue_stats[q]++)
> +#define __STAT_SAFE(hif_dev, expr) do { ((hif_dev)->htc_handle->drv_priv ? (expr) : 0); } while (0)
> +#define CAB_STAT_INC(priv) do { ((priv)->debug.tx_stats.cab_queued++); } while (0)
> +#define TX_QSTAT_INC(priv, q) do { ((priv)->debug.tx_stats.queue_stats[q]++); } while (0)
Hmm, is it really necessary to wrap these in do/while constructs? AFAICT
they're all simple statements already?
-Toke
On Thu, Dec 15, 2022, at 18:16, Toke Høiland-Jørgensen wrote:
>> index 30f0765fb9fd..237f4ec2cffd 100644
>> --- a/drivers/net/wireless/ath/ath9k/htc.h
>> +++ b/drivers/net/wireless/ath/ath9k/htc.h
>> @@ -327,9 +327,9 @@ static inline struct ath9k_htc_tx_ctl *HTC_SKB_CB(struct sk_buff *skb)
>> }
>>
>> #ifdef CONFIG_ATH9K_HTC_DEBUGFS
>> -#define __STAT_SAFE(hif_dev, expr) ((hif_dev)->htc_handle->drv_priv ? (expr) : 0)
>> -#define CAB_STAT_INC(priv) ((priv)->debug.tx_stats.cab_queued++)
>> -#define TX_QSTAT_INC(priv, q) ((priv)->debug.tx_stats.queue_stats[q]++)
>> +#define __STAT_SAFE(hif_dev, expr) do { ((hif_dev)->htc_handle->drv_priv ? (expr) : 0); } while (0)
>> +#define CAB_STAT_INC(priv) do { ((priv)->debug.tx_stats.cab_queued++); } while (0)
>> +#define TX_QSTAT_INC(priv, q) do { ((priv)->debug.tx_stats.queue_stats[q]++); } while (0)
>
> Hmm, is it really necessary to wrap these in do/while constructs? AFAICT
> they're all simple statements already?
It's generally safer to do the same thing on both side of the #ifdef.
The "do { } while (0)" is an empty statement that is needed to fix
the bug on the #else side. The expressions you have on the #ifdef
side can be used as values, and wrapping them in do{}while(0)
turns them into statements (without a value) as well, so fewer
things can go wrong when you only test one side.
I suppose the best solution would be to just use inline functions
for all of them and get rid of the macros.
Arnd
Toke Høiland-Jørgensen <[email protected]> writes:
> Arnd Bergmann <[email protected]> writes:
>
>> From: Arnd Bergmann <[email protected]>
>>
>> A previous cleanup patch accidentally broke some conditional
>> expressions by replacing the safe "do {} while (0)" constructs
>> with empty macros. gcc points this out when extra warnings
>> are enabled:
>>
>> drivers/net/wireless/ath/ath9k/hif_usb.c: In function 'ath9k_skb_queue_complete':
>> drivers/net/wireless/ath/ath9k/hif_usb.c:251:57: error: suggest braces around empty body in an 'else' statement [-Werror=empty-body]
>> 251 | TX_STAT_INC(hif_dev, skb_failed);
>>
>> Make both sets of macros proper expressions again.
>>
>> Fixes: d7fc76039b74 ("ath9k: htc: clean up statistics macros")
>> Signed-off-by: Arnd Bergmann <[email protected]>
>
> Acked-by: Toke Høiland-Jørgensen <[email protected]>
I'll queue this to v6.2.
--
https://patchwork.kernel.org/project/linux-wireless/list/
https://wireless.wiki.kernel.org/en/developers/documentation/submittingpatches
Kalle Valo <[email protected]> writes:
> Toke Høiland-Jørgensen <[email protected]> writes:
>
>> Arnd Bergmann <[email protected]> writes:
>>
>>> From: Arnd Bergmann <[email protected]>
>>>
>>> A previous cleanup patch accidentally broke some conditional
>>> expressions by replacing the safe "do {} while (0)" constructs
>>> with empty macros. gcc points this out when extra warnings
>>> are enabled:
>>>
>>> drivers/net/wireless/ath/ath9k/hif_usb.c: In function 'ath9k_skb_queue_complete':
>>> drivers/net/wireless/ath/ath9k/hif_usb.c:251:57: error: suggest braces around empty body in an 'else' statement [-Werror=empty-body]
>>> 251 | TX_STAT_INC(hif_dev, skb_failed);
>>>
>>> Make both sets of macros proper expressions again.
>>>
>>> Fixes: d7fc76039b74 ("ath9k: htc: clean up statistics macros")
>>> Signed-off-by: Arnd Bergmann <[email protected]>
>>
>> Acked-by: Toke Høiland-Jørgensen <[email protected]>
>
> I'll queue this to v6.2.
Sounds good, thanks!
-Toke