[gpu-drm-radeon] question about potential dead code in vce_v2_0_enable_mgcg()

From: Gustavo A. R. Silva
Date: Wed Jun 28 2017 - 10:22:50 EST



Hello everybody,

While looking into Coverity ID 1198635 I ran into the following piece of code at drivers/gpu/drm/radeon/vce_v2_0.c:107:

107void vce_v2_0_enable_mgcg(struct radeon_device *rdev, bool enable)
108{
109 bool sw_cg = false;
110
111 if (enable && (rdev->cg_flags & RADEON_CG_SUPPORT_VCE_MGCG)) {
112 if (sw_cg)
113 vce_v2_0_set_sw_cg(rdev, true);
114 else
115 vce_v2_0_set_dyn_cg(rdev, true);
116 } else {
117 vce_v2_0_disable_cg(rdev);
118
119 if (sw_cg)
120 vce_v2_0_set_sw_cg(rdev, false);
121 else
122 vce_v2_0_set_dyn_cg(rdev, false);
123 }
124}

The issue here is that local variable sw_cg is never updated again after its initialization; which cause some code to be logically dead.

My question here is if such variable is there for testing purposes or if it is a sort of an old code leftover that should be removed?

In any case I can send a patch to add a comment or remove the dead code.

I'd really appreciate any comments on this.

Thank you!
--
Gustavo A. R. Silva