All of lore.kernel.org
 help / color / mirror / Atom feed
* [PATCH] drm/i915/pmu: Fix build error with GCOV and AutoFDO enabled
@ 2025-05-29  4:29 Tzung-Bi Shih
  2025-05-29  5:15 ` ✓ i915.CI.BAT: success for " Patchwork
                   ` (2 more replies)
  0 siblings, 3 replies; 4+ messages in thread
From: Tzung-Bi Shih @ 2025-05-29  4:29 UTC (permalink / raw)
  To: jani.nikula, joonas.lahtinen, rodrigo.vivi, tursulin
  Cc: airlied, simona, nathan, intel-gfx, dri-devel, llvm, tzungbi

i915_pmu.c may fail to build with GCOV and AutoFDO enabled.

../drivers/gpu/drm/i915/i915_pmu.c:116:3: error: call to '__compiletime_assert_487' declared with 'error' attribute: BUILD_BUG_ON failed: bit > BITS_PER_TYPE(typeof_member(struct i915_pmu, enable)) - 1
  116 |                 BUILD_BUG_ON(bit >
      |                 ^

Here is a way to reproduce the issue:
$ git checkout v6.15
$ mkdir build
$ ./scripts/kconfig/merge_config.sh -O build -n -m <(cat <<EOF
CONFIG_DRM=y
CONFIG_PCI=y
CONFIG_DRM_I915=y

CONFIG_PERF_EVENTS=y

CONFIG_DEBUG_FS=y
CONFIG_GCOV_KERNEL=y
CONFIG_GCOV_PROFILE_ALL=y

CONFIG_AUTOFDO_CLANG=y
EOF
)
$ PATH=${PATH}:${HOME}/llvm-20.1.5-x86_64/bin make LLVM=1 O=build \
       olddefconfig
$ PATH=${PATH}:${HOME}/llvm-20.1.5-x86_64/bin make LLVM=1 O=build \
       CLANG_AUTOFDO_PROFILE=...PATH_TO_SOME_AFDO_PROFILE... \
       drivers/gpu/drm/i915/i915_pmu.o

Although not super sure what happened, by reviewing the code, it should
depend on `__builtin_constant_p(bit)` directly instead of assuming
`__builtin_constant_p(config)` makes `bit` a builtin constant.

Also fix a nit, to reuse the `bit` local variable.

Fixes: a644fde77ff7 ("drm/i915/pmu: Change bitmask of enabled events to u32")
Signed-off-by: Tzung-Bi Shih <tzungbi@kernel.org>
---
 drivers/gpu/drm/i915/i915_pmu.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_pmu.c b/drivers/gpu/drm/i915/i915_pmu.c
index e5a188ce3185..990bfaba3ce4 100644
--- a/drivers/gpu/drm/i915/i915_pmu.c
+++ b/drivers/gpu/drm/i915/i915_pmu.c
@@ -112,7 +112,7 @@ static u32 config_mask(const u64 config)
 {
 	unsigned int bit = config_bit(config);
 
-	if (__builtin_constant_p(config))
+	if (__builtin_constant_p(bit))
 		BUILD_BUG_ON(bit >
 			     BITS_PER_TYPE(typeof_member(struct i915_pmu,
 							 enable)) - 1);
@@ -121,7 +121,7 @@ static u32 config_mask(const u64 config)
 			     BITS_PER_TYPE(typeof_member(struct i915_pmu,
 							 enable)) - 1);
 
-	return BIT(config_bit(config));
+	return BIT(bit);
 }
 
 static bool is_engine_event(struct perf_event *event)
-- 
2.49.0.1266.g31b7d2e469-goog


^ permalink raw reply related	[flat|nested] 4+ messages in thread
end of thread, other threads:[~2025-06-02 22:17 UTC | newest]

Thread overview: 4+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2025-05-29  4:29 [PATCH] drm/i915/pmu: Fix build error with GCOV and AutoFDO enabled Tzung-Bi Shih
2025-05-29  5:15 ` ✓ i915.CI.BAT: success for " Patchwork
2025-05-29  6:59 ` ✗ i915.CI.Full: failure " Patchwork
2025-06-02 22:16 ` [PATCH] " Nathan Chancellor

This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.