The xe driver was using the drm_exec retry pointer directly to restart the locking loop after out-of-memory errors. This is relying on undocumented behaviour.
Instead add a drm_exec_retry() macro that can be used in this situation, and that also warns if the struct drm_exec is not newly (re-)initialized. Use that macro in xe. v2: - Only allow if the drm_exec context is newly initialized. (Christian) Signed-off-by: Thomas Hellström <[email protected]> --- drivers/gpu/drm/drm_exec.c | 3 --- drivers/gpu/drm/xe/xe_validation.h | 2 +- include/drm/drm_exec.h | 19 +++++++++++++++++++ 3 files changed, 20 insertions(+), 4 deletions(-) diff --git a/drivers/gpu/drm/drm_exec.c b/drivers/gpu/drm/drm_exec.c index 746210f3f6c2..7988f5e7d56a 100644 --- a/drivers/gpu/drm/drm_exec.c +++ b/drivers/gpu/drm/drm_exec.c @@ -48,9 +48,6 @@ * See struct dma_exec for more details. */ -/* Dummy value used to initially enter the retry loop */ -#define DRM_EXEC_DUMMY ((void *)~0) - /* Unlock all objects and drop references */ static void drm_exec_unlock_all(struct drm_exec *exec) { diff --git a/drivers/gpu/drm/xe/xe_validation.h b/drivers/gpu/drm/xe/xe_validation.h index a30e732c4d51..4cd955ce6cd2 100644 --- a/drivers/gpu/drm/xe/xe_validation.h +++ b/drivers/gpu/drm/xe/xe_validation.h @@ -146,7 +146,7 @@ bool xe_validation_should_retry(struct xe_validation_ctx *ctx, int *ret); #define xe_validation_retry_on_oom(_ctx, _ret) \ do { \ if (xe_validation_should_retry(_ctx, _ret)) \ - goto *__drm_exec_retry_ptr; \ + drm_exec_retry((_ctx)->exec); \ } while (0) /** diff --git a/include/drm/drm_exec.h b/include/drm/drm_exec.h index 18f84faabbb9..99c7e1bb3c5b 100644 --- a/include/drm/drm_exec.h +++ b/include/drm/drm_exec.h @@ -9,6 +9,12 @@ #define DRM_EXEC_INTERRUPTIBLE_WAIT BIT(0) #define DRM_EXEC_IGNORE_DUPLICATES BIT(1) +/* + * Dummy value used to initially enter the retry loop. + * internal use only. + */ +#define DRM_EXEC_DUMMY ((void *)~0) + struct drm_gem_object; /** @@ -142,6 +148,19 @@ static inline bool drm_exec_is_contended(struct drm_exec *exec) return !!exec->contended; } +/** + * drm_exec_retry() - Unconditionally restart the loop to grab all locks. + * @exec: drm_exec object + * + * Unconditionally retry the loop to lock all objects. For consistency, + * the exec object needs to be newly initialized. + */ +#define drm_exec_retry(_exec) \ + do { \ + WARN_ON((_exec)->contended != DRM_EXEC_DUMMY); \ + goto *__drm_exec_retry_ptr; \ + } while (0) + void drm_exec_init(struct drm_exec *exec, u32 flags, unsigned nr); void drm_exec_fini(struct drm_exec *exec); bool drm_exec_cleanup(struct drm_exec *exec); -- 2.54.0
