2017-06-25 19:11:03

by AbdAllah-MEZITI

[permalink] [raw]
Subject: [PATCH] staging: sm750fb: fix sparce warning.

This patch fixes the following sparce warnings: different lock contexts for basic block.

drivers/staging/sm750fb//sm750.c:159:13: warning: context imbalance in 'lynxfb_ops_fillrect' - different lock contexts for basic block
drivers/staging/sm750fb//sm750.c:231:9: warning: context imbalance in 'lynxfb_ops_copyarea' - different lock contexts for basic block
drivers/staging/sm750fb//sm750.c:235:13: warning: context imbalance in 'lynxfb_ops_imageblit' - different lock contexts for basic block

Signed-off-by: AbdAllah-MEZITI <[email protected]>
---
drivers/staging/sm750fb/sm750.c | 69 ++++++++++++++++++++++++++++-------------
1 file changed, 47 insertions(+), 22 deletions(-)

diff --git a/drivers/staging/sm750fb/sm750.c b/drivers/staging/sm750fb/sm750.c
index 664c220..5494a29 100644
--- a/drivers/staging/sm750fb/sm750.c
+++ b/drivers/staging/sm750fb/sm750.c
@@ -186,16 +186,24 @@ static void lynxfb_ops_fillrect(struct fb_info *info,
* If not use spin_lock,system will die if user load driver
* and immediately unload driver frequently (dual)
*/
- if (sm750_dev->fb_count > 1)
+ if (sm750_dev->fb_count > 1) {
spin_lock(&sm750_dev->slock);

- sm750_dev->accel.de_fillrect(&sm750_dev->accel,
- base, pitch, Bpp,
- region->dx, region->dy,
- region->width, region->height,
- color, rop);
- if (sm750_dev->fb_count > 1)
+ sm750_dev->accel.de_fillrect(&sm750_dev->accel,
+ base, pitch, Bpp,
+ region->dx, region->dy,
+ region->width, region->height,
+ color, rop);
+
spin_unlock(&sm750_dev->slock);
+ } else {
+ sm750_dev->accel.de_fillrect(&sm750_dev->accel,
+ base, pitch, Bpp,
+ region->dx, region->dy,
+ region->width, region->height,
+ color, rop);
+ }
+
}

static void lynxfb_ops_copyarea(struct fb_info *info,
@@ -220,16 +228,24 @@ static void lynxfb_ops_copyarea(struct fb_info *info,
* If not use spin_lock, system will die if user load driver
* and immediately unload driver frequently (dual)
*/
- if (sm750_dev->fb_count > 1)
+ if (sm750_dev->fb_count > 1) {
spin_lock(&sm750_dev->slock);

- sm750_dev->accel.de_copyarea(&sm750_dev->accel,
- base, pitch, region->sx, region->sy,
- base, pitch, Bpp, region->dx, region->dy,
- region->width, region->height,
- HW_ROP2_COPY);
- if (sm750_dev->fb_count > 1)
+ sm750_dev->accel.de_copyarea(&sm750_dev->accel,
+ base, pitch, region->sx, region->sy,
+ base, pitch, Bpp, region->dx, region->dy,
+ region->width, region->height,
+ HW_ROP2_COPY);
+
spin_unlock(&sm750_dev->slock);
+ } else {
+ sm750_dev->accel.de_copyarea(&sm750_dev->accel,
+ base, pitch, region->sx, region->sy,
+ base, pitch, Bpp, region->dx, region->dy,
+ region->width, region->height,
+ HW_ROP2_COPY);
+ }
+
}

static void lynxfb_ops_imageblit(struct fb_info *info,
@@ -269,17 +285,26 @@ static void lynxfb_ops_imageblit(struct fb_info *info,
* If not use spin_lock, system will die if user load driver
* and immediately unload driver frequently (dual)
*/
- if (sm750_dev->fb_count > 1)
+ if (sm750_dev->fb_count > 1) {
spin_lock(&sm750_dev->slock);

- sm750_dev->accel.de_imageblit(&sm750_dev->accel,
- image->data, image->width >> 3, 0,
- base, pitch, Bpp,
- image->dx, image->dy,
- image->width, image->height,
- fgcol, bgcol, HW_ROP2_COPY);
- if (sm750_dev->fb_count > 1)
+ sm750_dev->accel.de_imageblit(&sm750_dev->accel,
+ image->data, image->width >> 3, 0,
+ base, pitch, Bpp,
+ image->dx, image->dy,
+ image->width, image->height,
+ fgcol, bgcol, HW_ROP2_COPY);
+
spin_unlock(&sm750_dev->slock);
+ } else {
+ sm750_dev->accel.de_imageblit(&sm750_dev->accel,
+ image->data, image->width >> 3, 0,
+ base, pitch, Bpp,
+ image->dx, image->dy,
+ image->width, image->height,
+ fgcol, bgcol, HW_ROP2_COPY);
+ }
+
}

static int lynxfb_ops_pan_display(struct fb_var_screeninfo *var,
--
2.7.4


2017-06-25 20:20:50

by Frans Klaver

[permalink] [raw]
Subject: Re: [PATCH] staging: sm750fb: fix sparce warning.



On 25 June 2017 21:10:36 CEST, AbdAllah-MEZITI <[email protected]> wrote:
>This patch fixes the following sparce warnings: different lock contexts
>for basic block.
>
>drivers/staging/sm750fb//sm750.c:159:13: warning: context imbalance in
>'lynxfb_ops_fillrect' - different lock contexts for basic block
>drivers/staging/sm750fb//sm750.c:231:9: warning: context imbalance in
>'lynxfb_ops_copyarea' - different lock contexts for basic block
>drivers/staging/sm750fb//sm750.c:235:13: warning: context imbalance in
>'lynxfb_ops_imageblit' - different lock contexts for basic block
>
>Signed-off-by: AbdAllah-MEZITI <[email protected]>
>---
>drivers/staging/sm750fb/sm750.c | 69
>++++++++++++++++++++++++++++-------------
> 1 file changed, 47 insertions(+), 22 deletions(-)
>
>diff --git a/drivers/staging/sm750fb/sm750.c
>b/drivers/staging/sm750fb/sm750.c
>index 664c220..5494a29 100644
>--- a/drivers/staging/sm750fb/sm750.c
>+++ b/drivers/staging/sm750fb/sm750.c
>@@ -186,16 +186,24 @@ static void lynxfb_ops_fillrect(struct fb_info
>*info,
> * If not use spin_lock,system will die if user load driver
> * and immediately unload driver frequently (dual)
> */
>- if (sm750_dev->fb_count > 1)
>+ if (sm750_dev->fb_count > 1) {
> spin_lock(&sm750_dev->slock);
>
>- sm750_dev->accel.de_fillrect(&sm750_dev->accel,
>- base, pitch, Bpp,
>- region->dx, region->dy,
>- region->width, region->height,
>- color, rop);
>- if (sm750_dev->fb_count > 1)
>+ sm750_dev->accel.de_fillrect(&sm750_dev->accel,
>+ base, pitch, Bpp,
>+ region->dx, region->dy,
>+ region->width, region->height,
>+ color, rop);
>+
> spin_unlock(&sm750_dev->slock);
>+ } else {
>+ sm750_dev->accel.de_fillrect(&sm750_dev->accel,
>+ base, pitch, Bpp,
>+ region->dx, region->dy,
>+ region->width, region->height,
>+ color, rop);
>+ }
>+
> }
>
> static void lynxfb_ops_copyarea(struct fb_info *info,
>@@ -220,16 +228,24 @@ static void lynxfb_ops_copyarea(struct fb_info
>*info,
> * If not use spin_lock, system will die if user load driver
> * and immediately unload driver frequently (dual)
> */
>- if (sm750_dev->fb_count > 1)
>+ if (sm750_dev->fb_count > 1) {
> spin_lock(&sm750_dev->slock);
>
>- sm750_dev->accel.de_copyarea(&sm750_dev->accel,
>- base, pitch, region->sx, region->sy,
>- base, pitch, Bpp, region->dx, region->dy,
>- region->width, region->height,
>- HW_ROP2_COPY);
>- if (sm750_dev->fb_count > 1)
>+ sm750_dev->accel.de_copyarea(&sm750_dev->accel,
>+ base, pitch, region->sx, region->sy,
>+ base, pitch, Bpp, region->dx, region->dy,
>+ region->width, region->height,
>+ HW_ROP2_COPY);
>+
> spin_unlock(&sm750_dev->slock);
>+ } else {
>+ sm750_dev->accel.de_copyarea(&sm750_dev->accel,
>+ base, pitch, region->sx, region->sy,
>+ base, pitch, Bpp, region->dx, region->dy,
>+ region->width, region->height,
>+ HW_ROP2_COPY);
>+ }
>+
> }
>
> static void lynxfb_ops_imageblit(struct fb_info *info,
>@@ -269,17 +285,26 @@ static void lynxfb_ops_imageblit(struct fb_info
>*info,
> * If not use spin_lock, system will die if user load driver
> * and immediately unload driver frequently (dual)
> */
>- if (sm750_dev->fb_count > 1)
>+ if (sm750_dev->fb_count > 1) {
> spin_lock(&sm750_dev->slock);
>
>- sm750_dev->accel.de_imageblit(&sm750_dev->accel,
>- image->data, image->width >> 3, 0,
>- base, pitch, Bpp,
>- image->dx, image->dy,
>- image->width, image->height,
>- fgcol, bgcol, HW_ROP2_COPY);
>- if (sm750_dev->fb_count > 1)
>+ sm750_dev->accel.de_imageblit(&sm750_dev->accel,
>+ image->data, image->width >> 3, 0,
>+ base, pitch, Bpp,
>+ image->dx, image->dy,
>+ image->width, image->height,
>+ fgcol, bgcol, HW_ROP2_COPY);
>+
> spin_unlock(&sm750_dev->slock);
>+ } else {
>+ sm750_dev->accel.de_imageblit(&sm750_dev->accel,
>+ image->data, image->width >> 3, 0,
>+ base, pitch, Bpp,
>+ image->dx, image->dy,
>+ image->width, image->height,
>+ fgcol, bgcol, HW_ROP2_COPY);
>+ }
>+
> }
>
> static int lynxfb_ops_pan_display(struct fb_var_screeninfo *var,

I believe a similar change has been NACKed on the basis that you're duplicating code to work around some warning a tool generated. I think we should always take the lock, if we do anything about this. Since it's a spin lock, the penalty should not be very high.

Frans