On Mon, Jul 31, 2023 at 02:36:24PM +0200, Christian König wrote:
> GCC forbids to jump to labels in loop conditions and a new clang
> check stumbled over this.
>
> So instead using a local label inside the loop condition use an
> unique label outside of it.
>
> Fixes: commit 09593216bff1 ("drm: execution context for GEM buffers v7")
> Link: https://gcc.gnu.org/onlinedocs/gcc/Statement-Exprs.html
> Link: https://github.com/ClangBuiltLinux/linux/issues/1890
> Link:
> https://github.com/llvm/llvm-project/commit/20219106060208f0c2f5d096eb3aed7b712f5067
> Reported-by: Nathan Chancellor <nat...@kernel.org>
> Reported-by: Naresh Kamboju <naresh.kamb...@linaro.org>
> CC: Boris Brezillon <boris.brezil...@collabora.com>
> Signed-off-by: Christian König <christian.koe...@amd.com>
Passes my build tests and I inspected the preprocessed output to make
sure it should work. I ran the KUnit tests, which all pass (although [1]
is needed to fix a tangential issue):
Tested-by: Nathan Chancellor <nat...@kernel.org>
Thanks for fixing this!
[1]: https://lore.kernel.org/20230728183400.306193-1-arthurgri...@riseup.net/
> ---
> include/drm/drm_exec.h | 14 +++++++-------
> 1 file changed, 7 insertions(+), 7 deletions(-)
>
> diff --git a/include/drm/drm_exec.h b/include/drm/drm_exec.h
> index 73205afec162..e0462361adf9 100644
> --- a/include/drm/drm_exec.h
> +++ b/include/drm/drm_exec.h
> @@ -3,6 +3,7 @@
> #ifndef __DRM_EXEC_H__
> #define __DRM_EXEC_H__
>
> +#include <linux/compiler.h>
> #include <linux/ww_mutex.h>
>
> #define DRM_EXEC_INTERRUPTIBLE_WAIT BIT(0)
> @@ -74,13 +75,12 @@ struct drm_exec {
> * Since labels can't be defined local to the loops body we use a jump
> pointer
> * to make sure that the retry is only used from within the loops body.
> */
> -#define drm_exec_until_all_locked(exec) \
> - for (void *__drm_exec_retry_ptr; ({ \
> - __label__ __drm_exec_retry; \
> -__drm_exec_retry: \
> - __drm_exec_retry_ptr = &&__drm_exec_retry; \
> - (void)__drm_exec_retry_ptr; \
> - drm_exec_cleanup(exec); \
> +#define drm_exec_until_all_locked(exec)
> \
> +__PASTE(__drm_exec_, __LINE__):
> \
> + for (void *__drm_exec_retry_ptr; ({ \
> + __drm_exec_retry_ptr = &&__PASTE(__drm_exec_, __LINE__);\
> + (void)__drm_exec_retry_ptr; \
> + drm_exec_cleanup(exec); \
> });)
>
> /**
> --
> 2.34.1
>
>
