[PATCH v2] include: linux/iopoll.h: silence warning when timeout_us contains *

[PATCH v2] include: linux/iopoll.h: silence warning when timeout_us contains *

[Ahmad Fatoum]

We evaluate timeout_us for truthiness to determine whether we are
entering an infinite poll loop. When timeout_us contains a
multiplication, GCC will warn about it and suggest replacing the *
with &&. Silence this warning by comparing directly against 0.

Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
---
v1 -> v2:
  - squash change adding parens around timeout_us macro arg
---
 include/linux/iopoll.h | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/include/linux/iopoll.h b/include/linux/iopoll.h
index 8bf912e173b3..96b17dee48c9 100644
--- a/include/linux/iopoll.h
+++ b/include/linux/iopoll.h
@@ -32,13 +32,13 @@
 #define read_poll_timeout(op, val, cond, timeout_us, args...)	\
 ({ \
 	uint64_t start; \
-	if (!IN_PBL && timeout_us) \
+	if (!IN_PBL && (timeout_us) != 0) \
 		start = get_time_ns(); \
 	for (;;) { \
 		(val) = op(args); \
 		if (cond) \
 			break; \
-		if (!IN_PBL && timeout_us && \
+		if (!IN_PBL && (timeout_us) != 0 && \
 		    is_timeout(start, ((timeout_us) * USECOND))) { \
 			(val) = op(args); \
 			break; \
-- 
2.30.2

Re: [PATCH v2] include: linux/iopoll.h: silence warning when timeout_us contains *

[Sascha Hauer]

On Wed, Jan 11, 2023 at 08:49:57AM +0100, Ahmad Fatoum wrote:
> We evaluate timeout_us for truthiness to determine whether we are
> entering an infinite poll loop. When timeout_us contains a
> multiplication, GCC will warn about it and suggest replacing the *
> with &&. Silence this warning by comparing directly against 0.
> 
> Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
> ---
> v1 -> v2:
>   - squash change adding parens around timeout_us macro arg
> ---
>  include/linux/iopoll.h | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)

Applied, thanks

Sascha

> 
> diff --git a/include/linux/iopoll.h b/include/linux/iopoll.h
> index 8bf912e173b3..96b17dee48c9 100644
> --- a/include/linux/iopoll.h
> +++ b/include/linux/iopoll.h
> @@ -32,13 +32,13 @@
>  #define read_poll_timeout(op, val, cond, timeout_us, args...)	\
>  ({ \
>  	uint64_t start; \
> -	if (!IN_PBL && timeout_us) \
> +	if (!IN_PBL && (timeout_us) != 0) \
>  		start = get_time_ns(); \
>  	for (;;) { \
>  		(val) = op(args); \
>  		if (cond) \
>  			break; \
> -		if (!IN_PBL && timeout_us && \
> +		if (!IN_PBL && (timeout_us) != 0 && \
>  		    is_timeout(start, ((timeout_us) * USECOND))) { \
>  			(val) = op(args); \
>  			break; \
> -- 
> 2.30.2
> 
> 
> 

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