From: Colin Ian King <[email protected]>
Currently a loop scans through the connector list checking
for connectors that do not match a specific criteria. The
use of the continue statement is a little unintuitive and
can confuse static analysis checking. Invert the criteria
matching logic and use a break to terminate the loop once
the first suitable connector has been found.
Thanks to Patrik Jakobsson for explaining the original
intent of the code and suggesting this change.
Addresses-Coverity: ("Continue has no effect")
Signed-off-by: Colin Ian King <[email protected]>
---
drivers/gpu/drm/gma500/oaktrail_lvds.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/gma500/oaktrail_lvds.c b/drivers/gpu/drm/gma500/oaktrail_lvds.c
index 432bdcc57ac9..8541dcf237eb 100644
--- a/drivers/gpu/drm/gma500/oaktrail_lvds.c
+++ b/drivers/gpu/drm/gma500/oaktrail_lvds.c
@@ -113,8 +113,8 @@ static void oaktrail_lvds_mode_set(struct drm_encoder *encoder,
/* Find the connector we're trying to set up */
list_for_each_entry(connector, &mode_config->connector_list, head) {
- if (!connector->encoder || connector->encoder->crtc != crtc)
- continue;
+ if (connector->encoder && connector->encoder->crtc == crtc)
+ break;
}
if (!connector) {
--
2.31.1
On Fri, Jun 18, 2021 at 8:35 PM Colin King <[email protected]> wrote:
>
> From: Colin Ian King <[email protected]>
>
> Currently a loop scans through the connector list checking
> for connectors that do not match a specific criteria. The
> use of the continue statement is a little unintuitive and
> can confuse static analysis checking. Invert the criteria
> matching logic and use a break to terminate the loop once
> the first suitable connector has been found.
>
> Thanks to Patrik Jakobsson for explaining the original
> intent of the code and suggesting this change.
Applied to drm-misc-next
Thanks for the patch!
On Fri, Jun 18, 2021 at 07:35:24PM +0100, Colin King wrote:
> From: Colin Ian King <[email protected]>
>
> Currently a loop scans through the connector list checking
> for connectors that do not match a specific criteria. The
> use of the continue statement is a little unintuitive and
> can confuse static analysis checking. Invert the criteria
> matching logic and use a break to terminate the loop once
> the first suitable connector has been found.
>
> Thanks to Patrik Jakobsson for explaining the original
> intent of the code and suggesting this change.
>
> Addresses-Coverity: ("Continue has no effect")
> Signed-off-by: Colin Ian King <[email protected]>
> ---
> drivers/gpu/drm/gma500/oaktrail_lvds.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/gpu/drm/gma500/oaktrail_lvds.c b/drivers/gpu/drm/gma500/oaktrail_lvds.c
> index 432bdcc57ac9..8541dcf237eb 100644
> --- a/drivers/gpu/drm/gma500/oaktrail_lvds.c
> +++ b/drivers/gpu/drm/gma500/oaktrail_lvds.c
> @@ -113,8 +113,8 @@ static void oaktrail_lvds_mode_set(struct drm_encoder *encoder,
>
> /* Find the connector we're trying to set up */
> list_for_each_entry(connector, &mode_config->connector_list, head) {
> - if (!connector->encoder || connector->encoder->crtc != crtc)
> - continue;
> + if (connector->encoder && connector->encoder->crtc == crtc)
> + break;
> }
>
> if (!connector) {
This test is wrong/impossible. It should be:
if (list_entry_is_head(connector, &mode_config->connector_list,
head)) {
regards,
dan carpenter
On Sat, Jun 19, 2021 at 3:40 PM Dan Carpenter <[email protected]> wrote:
>
> On Fri, Jun 18, 2021 at 07:35:24PM +0100, Colin King wrote:
> > From: Colin Ian King <[email protected]>
> >
> > Currently a loop scans through the connector list checking
> > for connectors that do not match a specific criteria. The
> > use of the continue statement is a little unintuitive and
> > can confuse static analysis checking. Invert the criteria
> > matching logic and use a break to terminate the loop once
> > the first suitable connector has been found.
> >
> > Thanks to Patrik Jakobsson for explaining the original
> > intent of the code and suggesting this change.
> >
> > Addresses-Coverity: ("Continue has no effect")
> > Signed-off-by: Colin Ian King <[email protected]>
> > ---
> > drivers/gpu/drm/gma500/oaktrail_lvds.c | 4 ++--
> > 1 file changed, 2 insertions(+), 2 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/gma500/oaktrail_lvds.c b/drivers/gpu/drm/gma500/oaktrail_lvds.c
> > index 432bdcc57ac9..8541dcf237eb 100644
> > --- a/drivers/gpu/drm/gma500/oaktrail_lvds.c
> > +++ b/drivers/gpu/drm/gma500/oaktrail_lvds.c
> > @@ -113,8 +113,8 @@ static void oaktrail_lvds_mode_set(struct drm_encoder *encoder,
> >
> > /* Find the connector we're trying to set up */
> > list_for_each_entry(connector, &mode_config->connector_list, head) {
> > - if (!connector->encoder || connector->encoder->crtc != crtc)
> > - continue;
> > + if (connector->encoder && connector->encoder->crtc == crtc)
> > + break;
> > }
> >
> > if (!connector) {
>
> This test is wrong/impossible. It should be:
>
> if (list_entry_is_head(connector, &mode_config->connector_list,
> head)) {
Right, we should be back at the head if no match was found. Actually,
when looking closer, we should use drm_for_each_connector_iter() when
walking the connector list together with proper locking.
-Patrik
>
> regards,
> dan carpenter
>
>