[PATCH] drm/i915/gem: remove redundant assignments to variable ret

[PATCH] drm/i915/gem: remove redundant assignments to variable ret

[Colin Ian King]

The variable ret is being assigned with a value that is never read
both before and after a while-loop. The variable is being re-assigned
inside the while-loop and afterwards on the call to the function
i915_gem_object_lock_interruptible. Remove the redundants assignments.

Cleans up clang scan-build warnings:

warning: Although the value stored to 'ret' is used in the
enclosing expression, the value is never actually read
from 'ret' [deadcode.DeadStores]

warning: Value stored to 'ret' is never read [deadcode.DeadStores]

Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
---
 drivers/gpu/drm/i915/gem/i915_gem_userptr.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/i915/gem/i915_gem_userptr.c b/drivers/gpu/drm/i915/gem/i915_gem_userptr.c
index d4398948f016..b7e24476a0fd 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_userptr.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_userptr.c
@@ -292,7 +292,7 @@ int i915_gem_object_userptr_submit_init(struct drm_i915_gem_object *obj)
 	if (!i915_gem_object_is_readonly(obj))
 		gup_flags |= FOLL_WRITE;
 
-	pinned = ret = 0;
+	pinned = 0;
 	while (pinned < num_pages) {
 		ret = pin_user_pages_fast(obj->userptr.ptr + pinned * PAGE_SIZE,
 					  num_pages - pinned, gup_flags,
@@ -302,7 +302,6 @@ int i915_gem_object_userptr_submit_init(struct drm_i915_gem_object *obj)
 
 		pinned += ret;
 	}
-	ret = 0;
 
 	ret = i915_gem_object_lock_interruptible(obj, NULL);
 	if (ret)
-- 
2.37.3

Re: [PATCH] drm/i915/gem: remove redundant assignments to variable ret

[Tvrtko Ursulin]

On 07/10/2022 20:47, Colin Ian King wrote:
> The variable ret is being assigned with a value that is never read
> both before and after a while-loop. The variable is being re-assigned
> inside the while-loop and afterwards on the call to the function
> i915_gem_object_lock_interruptible. Remove the redundants assignments.
> 
> Cleans up clang scan-build warnings:
> 
> warning: Although the value stored to 'ret' is used in the
> enclosing expression, the value is never actually read
> from 'ret' [deadcode.DeadStores]
> 
> warning: Value stored to 'ret' is never read [deadcode.DeadStores]
> 
> Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
> ---
>   drivers/gpu/drm/i915/gem/i915_gem_userptr.c | 3 +--
>   1 file changed, 1 insertion(+), 2 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/gem/i915_gem_userptr.c b/drivers/gpu/drm/i915/gem/i915_gem_userptr.c
> index d4398948f016..b7e24476a0fd 100644
> --- a/drivers/gpu/drm/i915/gem/i915_gem_userptr.c
> +++ b/drivers/gpu/drm/i915/gem/i915_gem_userptr.c
> @@ -292,7 +292,7 @@ int i915_gem_object_userptr_submit_init(struct drm_i915_gem_object *obj)
>   	if (!i915_gem_object_is_readonly(obj))
>   		gup_flags |= FOLL_WRITE;
>   
> -	pinned = ret = 0;
> +	pinned = 0;
>   	while (pinned < num_pages) {
>   		ret = pin_user_pages_fast(obj->userptr.ptr + pinned * PAGE_SIZE,
>   					  num_pages - pinned, gup_flags,
> @@ -302,7 +302,6 @@ int i915_gem_object_userptr_submit_init(struct drm_i915_gem_object *obj)
>   
>   		pinned += ret;
>   	}
> -	ret = 0;
>   
>   	ret = i915_gem_object_lock_interruptible(obj, NULL);
>   	if (ret)

Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>

Thanks for the cleanup, will merge.

Regards,

Tvrtko