diff options
| -rw-r--r-- | drivers/gpu/drm/msm/msm_gem.c | 41 | ||||
| -rw-r--r-- | drivers/gpu/drm/msm/msm_gem.h | 37 | ||||
| -rw-r--r-- | drivers/gpu/drm/msm/msm_gem_shrinker.c | 80 | ||||
| -rw-r--r-- | drivers/gpu/drm/msm/msm_gem_submit.c | 8 | ||||
| -rw-r--r-- | drivers/gpu/drm/msm/msm_gem_vma.c | 24 |
5 files changed, 151 insertions, 39 deletions
diff --git a/drivers/gpu/drm/msm/msm_gem.c b/drivers/gpu/drm/msm/msm_gem.c index 664fb801c221..82293806219a 100644 --- a/drivers/gpu/drm/msm/msm_gem.c +++ b/drivers/gpu/drm/msm/msm_gem.c @@ -48,6 +48,7 @@ static void put_iova_spaces(struct drm_gem_object *obj, struct drm_gpuvm *vm, bo static void detach_vm(struct drm_gem_object *obj, struct msm_gem_vm *vm) { msm_gem_assert_locked(obj); + drm_gpuvm_resv_assert_held(&vm->base); struct drm_gpuvm_bo *vm_bo = drm_gpuvm_bo_find(&vm->base, obj); if (vm_bo) { @@ -68,6 +69,7 @@ static void detach_vm(struct drm_gem_object *obj, struct msm_gem_vm *vm) static void msm_gem_close(struct drm_gem_object *obj, struct drm_file *file) { struct msm_context *ctx = file->driver_priv; + struct drm_exec exec; update_ctx_mem(file, -obj->size); @@ -86,10 +88,10 @@ static void msm_gem_close(struct drm_gem_object *obj, struct drm_file *file) dma_resv_wait_timeout(obj->resv, DMA_RESV_USAGE_READ, false, msecs_to_jiffies(1000)); - msm_gem_lock(obj); + msm_gem_lock_vm_and_obj(&exec, obj, ctx->vm); put_iova_spaces(obj, &ctx->vm->base, true); detach_vm(obj, ctx->vm); - msm_gem_unlock(obj); + drm_exec_fini(&exec); /* drop locks */ } /* @@ -551,11 +553,12 @@ int msm_gem_get_and_pin_iova_range(struct drm_gem_object *obj, struct msm_gem_vm *vm, uint64_t *iova, u64 range_start, u64 range_end) { + struct drm_exec exec; int ret; - msm_gem_lock(obj); + msm_gem_lock_vm_and_obj(&exec, obj, vm); ret = get_and_pin_iova_range_locked(obj, vm, iova, range_start, range_end); - msm_gem_unlock(obj); + drm_exec_fini(&exec); /* drop locks */ return ret; } @@ -575,16 +578,17 @@ int msm_gem_get_iova(struct drm_gem_object *obj, struct msm_gem_vm *vm, uint64_t *iova) { struct msm_gem_vma *vma; + struct drm_exec exec; int ret = 0; - msm_gem_lock(obj); + msm_gem_lock_vm_and_obj(&exec, obj, vm); vma = get_vma_locked(obj, vm, 0, U64_MAX); if (IS_ERR(vma)) { ret = PTR_ERR(vma); } else { *iova = vma->base.va.addr; } - msm_gem_unlock(obj); + drm_exec_fini(&exec); /* drop locks */ return ret; } @@ -613,9 +617,10 @@ static int clear_iova(struct drm_gem_object *obj, int msm_gem_set_iova(struct drm_gem_object *obj, struct msm_gem_vm *vm, uint64_t iova) { + struct drm_exec exec; int ret = 0; - msm_gem_lock(obj); + msm_gem_lock_vm_and_obj(&exec, obj, vm); if (!iova) { ret = clear_iova(obj, vm); } else { @@ -628,7 +633,7 @@ int msm_gem_set_iova(struct drm_gem_object *obj, ret = -EBUSY; } } - msm_gem_unlock(obj); + drm_exec_fini(&exec); /* drop locks */ return ret; } @@ -642,14 +647,15 @@ void msm_gem_unpin_iova(struct drm_gem_object *obj, struct msm_gem_vm *vm) { struct msm_gem_vma *vma; + struct drm_exec exec; - msm_gem_lock(obj); + msm_gem_lock_vm_and_obj(&exec, obj, vm); vma = lookup_vma(obj, vm); if (vma) { msm_gem_unpin_locked(obj); } detach_vm(obj, vm); - msm_gem_unlock(obj); + drm_exec_fini(&exec); /* drop locks */ } int msm_gem_dumb_create(struct drm_file *file, struct drm_device *dev, @@ -1021,12 +1027,27 @@ static void msm_gem_free_object(struct drm_gem_object *obj) struct msm_gem_object *msm_obj = to_msm_bo(obj); struct drm_device *dev = obj->dev; struct msm_drm_private *priv = dev->dev_private; + struct drm_exec exec; mutex_lock(&priv->obj_lock); list_del(&msm_obj->node); mutex_unlock(&priv->obj_lock); + /* + * We need to lock any VMs the object is still attached to, but not + * the object itself (see explaination in msm_gem_assert_locked()), + * so just open-code this special case: + */ + drm_exec_init(&exec, 0, 0); + drm_exec_until_all_locked (&exec) { + struct drm_gpuvm_bo *vm_bo; + drm_gem_for_each_gpuvm_bo (vm_bo, obj) { + drm_exec_lock_obj(&exec, drm_gpuvm_resv_obj(vm_bo->vm)); + drm_exec_retry_on_contention(&exec); + } + } put_iova_spaces(obj, NULL, true); + drm_exec_fini(&exec); /* drop locks */ if (drm_gem_is_imported(obj)) { GEM_WARN_ON(msm_obj->vaddr); diff --git a/drivers/gpu/drm/msm/msm_gem.h b/drivers/gpu/drm/msm/msm_gem.h index 4112370baf34..33885a08cdd7 100644 --- a/drivers/gpu/drm/msm/msm_gem.h +++ b/drivers/gpu/drm/msm/msm_gem.h @@ -62,12 +62,6 @@ struct msm_gem_vm { */ struct drm_mm mm; - /** @mm_lock: protects @mm node allocation/removal */ - struct spinlock mm_lock; - - /** @vm_lock: protects gpuvm insert/remove/traverse */ - struct mutex vm_lock; - /** @mmu: The mmu object which manages the pgtables */ struct msm_mmu *mmu; @@ -246,6 +240,37 @@ msm_gem_unlock(struct drm_gem_object *obj) dma_resv_unlock(obj->resv); } +/** + * msm_gem_lock_vm_and_obj() - Helper to lock an obj + VM + * @exec: the exec context helper which will be initalized + * @obj: the GEM object to lock + * @vm: the VM to lock + * + * Operations which modify a VM frequently need to lock both the VM and + * the object being mapped/unmapped/etc. This helper uses drm_exec to + * acquire both locks, dealing with potential deadlock/backoff scenarios + * which arise when multiple locks are involved. + */ +static inline int +msm_gem_lock_vm_and_obj(struct drm_exec *exec, + struct drm_gem_object *obj, + struct msm_gem_vm *vm) +{ + int ret = 0; + + drm_exec_init(exec, 0, 2); + drm_exec_until_all_locked (exec) { + ret = drm_exec_lock_obj(exec, drm_gpuvm_resv_obj(&vm->base)); + if (!ret && (obj->resv != drm_gpuvm_resv(&vm->base))) + ret = drm_exec_lock_obj(exec, obj); + drm_exec_retry_on_contention(exec); + if (GEM_WARN_ON(ret)) + break; + } + + return ret; +} + static inline void msm_gem_assert_locked(struct drm_gem_object *obj) { diff --git a/drivers/gpu/drm/msm/msm_gem_shrinker.c b/drivers/gpu/drm/msm/msm_gem_shrinker.c index de185fc34084..5faf6227584a 100644 --- a/drivers/gpu/drm/msm/msm_gem_shrinker.c +++ b/drivers/gpu/drm/msm/msm_gem_shrinker.c @@ -44,6 +44,75 @@ msm_gem_shrinker_count(struct shrinker *shrinker, struct shrink_control *sc) } static bool +with_vm_locks(struct ww_acquire_ctx *ticket, + void (*fn)(struct drm_gem_object *obj), + struct drm_gem_object *obj) +{ + /* + * Track last locked entry for for unwinding locks in error and + * success paths + */ + struct drm_gpuvm_bo *vm_bo, *last_locked = NULL; + int ret = 0; + + drm_gem_for_each_gpuvm_bo (vm_bo, obj) { + struct dma_resv *resv = drm_gpuvm_resv(vm_bo->vm); + + if (resv == obj->resv) + continue; + + ret = dma_resv_lock(resv, ticket); + + /* + * Since we already skip the case when the VM and obj + * share a resv (ie. _NO_SHARE objs), we don't expect + * to hit a double-locking scenario... which the lock + * unwinding cannot really cope with. + */ + WARN_ON(ret == -EALREADY); + + /* + * Don't bother with slow-lock / backoff / retry sequence, + * if we can't get the lock just give up and move on to + * the next object. + */ + if (ret) + goto out_unlock; + + /* + * Hold a ref to prevent the vm_bo from being freed + * and removed from the obj's gpuva list, as that would + * would result in missing the unlock below + */ + drm_gpuvm_bo_get(vm_bo); + + last_locked = vm_bo; + } + + fn(obj); + +out_unlock: + if (last_locked) { + drm_gem_for_each_gpuvm_bo (vm_bo, obj) { + struct dma_resv *resv = drm_gpuvm_resv(vm_bo->vm); + + if (resv == obj->resv) + continue; + + dma_resv_unlock(resv); + + /* Drop the ref taken while locking: */ + drm_gpuvm_bo_put(vm_bo); + + if (last_locked == vm_bo) + break; + } + } + + return ret == 0; +} + +static bool purge(struct drm_gem_object *obj, struct ww_acquire_ctx *ticket) { if (!is_purgeable(to_msm_bo(obj))) @@ -52,9 +121,7 @@ purge(struct drm_gem_object *obj, struct ww_acquire_ctx *ticket) if (msm_gem_active(obj)) return false; - msm_gem_purge(obj); - - return true; + return with_vm_locks(ticket, msm_gem_purge, obj); } static bool @@ -66,9 +133,7 @@ evict(struct drm_gem_object *obj, struct ww_acquire_ctx *ticket) if (msm_gem_active(obj)) return false; - msm_gem_evict(obj); - - return true; + return with_vm_locks(ticket, msm_gem_evict, obj); } static bool @@ -100,6 +165,7 @@ static unsigned long msm_gem_shrinker_scan(struct shrinker *shrinker, struct shrink_control *sc) { struct msm_drm_private *priv = shrinker->private_data; + struct ww_acquire_ctx ticket; struct { struct drm_gem_lru *lru; bool (*shrink)(struct drm_gem_object *obj, struct ww_acquire_ctx *ticket); @@ -124,7 +190,7 @@ msm_gem_shrinker_scan(struct shrinker *shrinker, struct shrink_control *sc) drm_gem_lru_scan(stages[i].lru, nr, &stages[i].remaining, stages[i].shrink, - NULL); + &ticket); nr -= stages[i].freed; freed += stages[i].freed; remaining += stages[i].remaining; diff --git a/drivers/gpu/drm/msm/msm_gem_submit.c b/drivers/gpu/drm/msm/msm_gem_submit.c index 0cc30660c9c5..50060d934469 100644 --- a/drivers/gpu/drm/msm/msm_gem_submit.c +++ b/drivers/gpu/drm/msm/msm_gem_submit.c @@ -257,11 +257,17 @@ out: /* This is where we make sure all the bo's are reserved and pin'd: */ static int submit_lock_objects(struct msm_gem_submit *submit) { + unsigned flags = DRM_EXEC_INTERRUPTIBLE_WAIT; int ret; - drm_exec_init(&submit->exec, DRM_EXEC_INTERRUPTIBLE_WAIT, submit->nr_bos); + drm_exec_init(&submit->exec, flags, submit->nr_bos); drm_exec_until_all_locked (&submit->exec) { + ret = drm_exec_lock_obj(&submit->exec, + drm_gpuvm_resv_obj(&submit->vm->base)); + drm_exec_retry_on_contention(&submit->exec); + if (ret) + goto error; for (unsigned i = 0; i < submit->nr_bos; i++) { struct drm_gem_object *obj = submit->bos[i].obj; ret = drm_exec_prepare_obj(&submit->exec, obj, 1); diff --git a/drivers/gpu/drm/msm/msm_gem_vma.c b/drivers/gpu/drm/msm/msm_gem_vma.c index 1f4c9b5c2e8f..ccb20897a2b0 100644 --- a/drivers/gpu/drm/msm/msm_gem_vma.c +++ b/drivers/gpu/drm/msm/msm_gem_vma.c @@ -92,15 +92,13 @@ void msm_gem_vma_close(struct msm_gem_vma *vma) GEM_WARN_ON(vma->mapped); - spin_lock(&vm->mm_lock); + drm_gpuvm_resv_assert_held(&vm->base); + if (vma->base.va.addr) drm_mm_remove_node(&vma->node); - spin_unlock(&vm->mm_lock); - mutex_lock(&vm->vm_lock); drm_gpuva_remove(&vma->base); drm_gpuva_unlink(&vma->base); - mutex_unlock(&vm->vm_lock); kfree(vma); } @@ -114,16 +112,16 @@ msm_gem_vma_new(struct msm_gem_vm *vm, struct drm_gem_object *obj, struct msm_gem_vma *vma; int ret; + drm_gpuvm_resv_assert_held(&vm->base); + vma = kzalloc(sizeof(*vma), GFP_KERNEL); if (!vma) return ERR_PTR(-ENOMEM); if (vm->managed) { - spin_lock(&vm->mm_lock); ret = drm_mm_insert_node_in_range(&vm->mm, &vma->node, obj->size, PAGE_SIZE, 0, range_start, range_end, 0); - spin_unlock(&vm->mm_lock); if (ret) goto err_free_vma; @@ -137,9 +135,7 @@ msm_gem_vma_new(struct msm_gem_vm *vm, struct drm_gem_object *obj, drm_gpuva_init(&vma->base, range_start, range_end - range_start, obj, 0); vma->mapped = false; - mutex_lock(&vm->vm_lock); ret = drm_gpuva_insert(&vm->base, &vma->base); - mutex_unlock(&vm->vm_lock); if (ret) goto err_free_range; @@ -149,18 +145,14 @@ msm_gem_vma_new(struct msm_gem_vm *vm, struct drm_gem_object *obj, goto err_va_remove; } - mutex_lock(&vm->vm_lock); drm_gpuvm_bo_extobj_add(vm_bo); drm_gpuva_link(&vma->base, vm_bo); - mutex_unlock(&vm->vm_lock); GEM_WARN_ON(drm_gpuvm_bo_put(vm_bo)); return vma; err_va_remove: - mutex_lock(&vm->vm_lock); drm_gpuva_remove(&vma->base); - mutex_unlock(&vm->vm_lock); err_free_range: if (vm->managed) drm_mm_remove_node(&vma->node); @@ -191,6 +183,11 @@ struct msm_gem_vm * msm_gem_vm_create(struct drm_device *drm, struct msm_mmu *mmu, const char *name, u64 va_start, u64 va_size, bool managed) { + /* + * We mostly want to use DRM_GPUVM_RESV_PROTECTED, except that + * makes drm_gpuvm_bo_evict() a no-op for extobjs (ie. we loose + * tracking that an extobj is evicted) :facepalm: + */ enum drm_gpuvm_flags flags = 0; struct msm_gem_vm *vm; struct drm_gem_object *dummy_gem; @@ -213,9 +210,6 @@ msm_gem_vm_create(struct drm_device *drm, struct msm_mmu *mmu, const char *name, va_start, va_size, 0, 0, &msm_gpuvm_ops); drm_gem_object_put(dummy_gem); - spin_lock_init(&vm->mm_lock); - mutex_init(&vm->vm_lock); - vm->mmu = mmu; vm->managed = managed; |