From f159c647b13b3cc9ae682f455b2858d2e1abd6be Mon Sep 17 00:00:00 2001 From: Nathan Chancellor Date: Fri, 15 May 2020 19:35:45 -0700 Subject: [PATCH] drm/i915: Mark check_shadow_context_ppgtt as maybe unused When CONFIG_DRM_I915_DEBUG_GEM is not set, clang warns: drivers/gpu/drm/i915/gvt/scheduler.c:884:1: warning: function 'check_shadow_context_ppgtt' is not needed and will not be emitted [-Wunneeded-internal-declaration] check_shadow_context_ppgtt(struct execlist_ring_context *c, struct intel_vgpu_mm *m) ^ 1 warning generated. This warning is similar to -Wunused-function but rather than warning that the function is completely unused, it warns that it is used in some expression within the file but that expression will be evaluated to a constant or be optimized away in the final assembly, essentially making it appeared used but really isn't. Usually, this happens when a function or variable is only used in sizeof, where it will appear to be used but will be evaluated at compile time and not be required to be emitted. In this case, the function is only used in GEM_BUG_ON, which is defined as BUILD_BUG_ON_INVALID, which intentionally follows this pattern. To fix this warning, add __maybe_unused to make it clear that this is intentional depending on the configuration. Fixes: bec3df930fbd ("drm/i915/gvt: Support PPGTT table load command") Link: https://github.com/ClangBuiltLinux/linux/issues/1027 Signed-off-by: Nathan Chancellor Reviewed-by: Chris Wilson Signed-off-by: Chris Wilson Link: https://patchwork.freedesktop.org/patch/msgid/20200516023545.3332334-1-natechancellor@gmail.com (cherry picked from commit 993fa32eb3d5ffb79e86a770ca982eb9c9f54011) Signed-off-by: Joonas Lahtinen --- drivers/gpu/drm/i915/gvt/scheduler.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/gpu/drm/i915/gvt/scheduler.c b/drivers/gpu/drm/i915/gvt/scheduler.c index c00189432b58..3a9bd8e4d8db 100644 --- a/drivers/gpu/drm/i915/gvt/scheduler.c +++ b/drivers/gpu/drm/i915/gvt/scheduler.c @@ -876,7 +876,7 @@ static void update_guest_pdps(struct intel_vgpu *vgpu, gpa + i * 8, &pdp[7 - i], 4); } -static bool +static __maybe_unused bool check_shadow_context_ppgtt(struct execlist_ring_context *c, struct intel_vgpu_mm *m) { if (m->ppgtt_mm.root_entry_type == GTT_TYPE_PPGTT_ROOT_L4_ENTRY) {