[PATCH 2/6] wifi: brcmfmac: use 'time_left' variable with wait_event_timeout()

Wolfram Sang posted 6 patches 1 year, 8 months ago
[PATCH 2/6] wifi: brcmfmac: use 'time_left' variable with wait_event_timeout()
Posted by Wolfram Sang 1 year, 8 months ago
There is a confusing pattern in the kernel to use a variable named 'timeout' to
store the result of wait_event_timeout() causing patterns like:

	timeout = wait_event_timeout(...)
	if (!timeout) return -ETIMEDOUT;

with all kinds of permutations. Use 'time_left' as a variable to make the code
self explaining.

Fix to the proper variable type 'long' while here.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
---
 .../wireless/broadcom/brcm80211/brcmfmac/cfg80211.c    | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c
index 5fe0e671ecb3..1585a5653ee4 100644
--- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c
+++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c
@@ -4071,7 +4071,7 @@ static void brcmf_report_wowl_wakeind(struct wiphy *wiphy, struct brcmf_if *ifp)
 	struct cfg80211_wowlan_wakeup *wakeup;
 	u32 wakeind;
 	s32 err;
-	int timeout;
+	long time_left;
 
 	err = brcmf_fil_iovar_data_get(ifp, "wowl_wakeind", &wake_ind_le,
 				       sizeof(wake_ind_le));
@@ -4113,10 +4113,10 @@ static void brcmf_report_wowl_wakeind(struct wiphy *wiphy, struct brcmf_if *ifp)
 		}
 		if (wakeind & BRCMF_WOWL_PFN_FOUND) {
 			brcmf_dbg(INFO, "WOWL Wake indicator: BRCMF_WOWL_PFN_FOUND\n");
-			timeout = wait_event_timeout(cfg->wowl.nd_data_wait,
-				cfg->wowl.nd_data_completed,
-				BRCMF_ND_INFO_TIMEOUT);
-			if (!timeout)
+			time_left = wait_event_timeout(cfg->wowl.nd_data_wait,
+						       cfg->wowl.nd_data_completed,
+						       BRCMF_ND_INFO_TIMEOUT);
+			if (!time_left)
 				bphy_err(drvr, "No result for wowl net detect\n");
 			else
 				wakeup_data.net_detect = cfg->wowl.nd_info;
-- 
2.43.0
Re: [PATCH 2/6] wifi: brcmfmac: use 'time_left' variable with wait_event_timeout()
Posted by Kalle Valo 1 year, 8 months ago
Wolfram Sang <wsa+renesas@sang-engineering.com> wrote:

> There is a confusing pattern in the kernel to use a variable named 'timeout' to
> store the result of wait_event_timeout() causing patterns like:
> 
> 	timeout = wait_event_timeout(...)
> 	if (!timeout) return -ETIMEDOUT;
> 
> with all kinds of permutations. Use 'time_left' as a variable to make the code
> self explaining.
> 
> Fix to the proper variable type 'long' while here.
> 
> Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
> Acked-by: Arend van Spriel <arend.vanspriel@broadcom.com>

4 patches applied to wireless-next.git, thanks.

158d5a1b3caa wifi: brcmfmac: use 'time_left' variable with wait_event_timeout()
0c0668813cc0 wifi: mwl8k: use 'time_left' variable with wait_for_completion_timeout()
a37f6947ff07 wifi: p54: use 'time_left' variable with wait_for_completion_interruptible_timeout()
a2ead3445a63 wifi: zd1211rw: use 'time_left' variable with wait_for_completion_timeout()

-- 
https://patchwork.kernel.org/project/linux-wireless/patch/20240603091541.8367-3-wsa+renesas@sang-engineering.com/

https://wireless.wiki.kernel.org/en/developers/documentation/submittingpatches
Re: [PATCH 2/6] wifi: brcmfmac: use 'time_left' variable with wait_event_timeout()
Posted by Arend van Spriel 1 year, 8 months ago
On 6/3/2024 11:15 AM, Wolfram Sang wrote:
> There is a confusing pattern in the kernel to use a variable named 'timeout' to
> store the result of wait_event_timeout() causing patterns like:
> 
> 	timeout = wait_event_timeout(...)
> 	if (!timeout) return -ETIMEDOUT;
> 
> with all kinds of permutations. Use 'time_left' as a variable to make the code
> self explaining.

I feel this type of changes fall into the category of bike-shedding. 
People should know how wait_event_timeout() works and then a variable 
name does not really matter.

> Fix to the proper variable type 'long' while here.

But it may have useful side-effects to go over the code with fresh look. 
Thanks.

Acked-by: Arend van Spriel <arend.vanspriel@broadcom.com>
> Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
> ---
>   .../wireless/broadcom/brcm80211/brcmfmac/cfg80211.c    | 10 +++++-----
>   1 file changed, 5 insertions(+), 5 deletions(-)
Re: [PATCH 2/6] wifi: brcmfmac: use 'time_left' variable with wait_event_timeout()
Posted by Wolfram Sang 1 year, 8 months ago
> I feel this type of changes fall into the category of bike-shedding. People

I have two motivations for this change: One may be bike-shedding, yet
"if (!timeout) return -ETIMEDOUT" looks stupid to me.

> should know how wait_event_timeout() works and then a variable name does not
> really matter.

And for a new developer, I am quite sure the change will help to
understand how wait_event-family() works. Especially given that
wait_event_interruptible() returns 0 if condition is true and
wait_event_interruptible_timeout() returns 0 if condition is false.

> > Fix to the proper variable type 'long' while here.
> 
> But it may have useful side-effects to go over the code with fresh look.

:)

> Acked-by: Arend van Spriel <arend.vanspriel@broadcom.com>

Thank you!