I noticed you were using IDRs where you could be using the more efficient IDAs, then while fixing that I noticed the lack of error handling, and I decided to follow that up with an efficiency improvement. There's probably a v2 of this to follow because I couldn't figure out how to properly handle one of the error cases ... see the comment embedded in one of the patches. Matthew Wilcox (4): drm/virtio: Replace IDRs with IDAs drm/virtio: Handle context ID allocation errors drm/virtio: Handle object ID allocation errors drm/virtio: Use IDAs more efficiently drivers/gpu/drm/virtio/virtgpu_drv.h | 9 ++--- drivers/gpu/drm/virtio/virtgpu_fb.c | 10 ++++-- drivers/gpu/drm/virtio/virtgpu_gem.c | 10 ++++-- drivers/gpu/drm/virtio/virtgpu_ioctl.c | 5 ++- drivers/gpu/drm/virtio/virtgpu_kms.c | 46 +++++++++----------------- drivers/gpu/drm/virtio/virtgpu_vq.c | 19 ++++------- 6 files changed, 44 insertions(+), 55 deletions(-) -- 2.19.0
These IDRs were only being used to allocate unique numbers, not to look up pointers, so they can use the more space-efficient IDA instead. Signed-off-by: Matthew Wilcox <willy at infradead.org> --- drivers/gpu/drm/virtio/virtgpu_drv.h | 6 ++---- drivers/gpu/drm/virtio/virtgpu_kms.c | 18 ++++-------------- drivers/gpu/drm/virtio/virtgpu_vq.c | 12 ++---------- 3 files changed, 8 insertions(+), 28 deletions(-) diff --git a/drivers/gpu/drm/virtio/virtgpu_drv.h b/drivers/gpu/drm/virtio/virtgpu_drv.h index 65605e207bbe..c4468a4e454e 100644 --- a/drivers/gpu/drm/virtio/virtgpu_drv.h +++ b/drivers/gpu/drm/virtio/virtgpu_drv.h @@ -180,8 +180,7 @@ struct virtio_gpu_device { struct kmem_cache *vbufs; bool vqs_ready; - struct idr resource_idr; - spinlock_t resource_idr_lock; + struct ida resource_ida; wait_queue_head_t resp_wq; /* current display info */ @@ -190,8 +189,7 @@ struct virtio_gpu_device { struct virtio_gpu_fence_driver fence_drv; - struct idr ctx_id_idr; - spinlock_t ctx_id_idr_lock; + struct ida ctx_id_ida; bool has_virgl_3d; diff --git a/drivers/gpu/drm/virtio/virtgpu_kms.c b/drivers/gpu/drm/virtio/virtgpu_kms.c index 65060c08522d..e2604fe1b4ae 100644 --- a/drivers/gpu/drm/virtio/virtgpu_kms.c +++ b/drivers/gpu/drm/virtio/virtgpu_kms.c @@ -55,21 +55,13 @@ static void virtio_gpu_config_changed_work_func(struct work_struct *work) static void virtio_gpu_ctx_id_get(struct virtio_gpu_device *vgdev, uint32_t *resid) { - int handle; - - idr_preload(GFP_KERNEL); - spin_lock(&vgdev->ctx_id_idr_lock); - handle = idr_alloc(&vgdev->ctx_id_idr, NULL, 1, 0, 0); - spin_unlock(&vgdev->ctx_id_idr_lock); - idr_preload_end(); + int handle = ida_alloc_min(&vgdev->ctx_id_ida, 1, GFP_KERNEL); *resid = handle; } static void virtio_gpu_ctx_id_put(struct virtio_gpu_device *vgdev, uint32_t id) { - spin_lock(&vgdev->ctx_id_idr_lock); - idr_remove(&vgdev->ctx_id_idr, id); - spin_unlock(&vgdev->ctx_id_idr_lock); + ida_free(&vgdev->ctx_id_ida, id); } static void virtio_gpu_context_create(struct virtio_gpu_device *vgdev, @@ -151,10 +143,8 @@ int virtio_gpu_driver_load(struct drm_device *dev, unsigned long flags) vgdev->dev = dev->dev; spin_lock_init(&vgdev->display_info_lock); - spin_lock_init(&vgdev->ctx_id_idr_lock); - idr_init(&vgdev->ctx_id_idr); - spin_lock_init(&vgdev->resource_idr_lock); - idr_init(&vgdev->resource_idr); + ida_init(&vgdev->ctx_id_ida); + ida_init(&vgdev->resource_ida); init_waitqueue_head(&vgdev->resp_wq); virtio_gpu_init_vq(&vgdev->ctrlq, virtio_gpu_dequeue_ctrl_func); virtio_gpu_init_vq(&vgdev->cursorq, virtio_gpu_dequeue_cursor_func); diff --git a/drivers/gpu/drm/virtio/virtgpu_vq.c b/drivers/gpu/drm/virtio/virtgpu_vq.c index 020070d483d3..58be09d2eed6 100644 --- a/drivers/gpu/drm/virtio/virtgpu_vq.c +++ b/drivers/gpu/drm/virtio/virtgpu_vq.c @@ -41,21 +41,13 @@ void virtio_gpu_resource_id_get(struct virtio_gpu_device *vgdev, uint32_t *resid) { - int handle; - - idr_preload(GFP_KERNEL); - spin_lock(&vgdev->resource_idr_lock); - handle = idr_alloc(&vgdev->resource_idr, NULL, 1, 0, GFP_NOWAIT); - spin_unlock(&vgdev->resource_idr_lock); - idr_preload_end(); + int handle = ida_alloc_min(&vgdev->resource_ida, 1, GFP_KERNEL); *resid = handle; } void virtio_gpu_resource_id_put(struct virtio_gpu_device *vgdev, uint32_t id) { - spin_lock(&vgdev->resource_idr_lock); - idr_remove(&vgdev->resource_idr, id); - spin_unlock(&vgdev->resource_idr_lock); + ida_free(&vgdev->resource_ida, id); } void virtio_gpu_ctrl_ack(struct virtqueue *vq) -- 2.19.0
Matthew Wilcox
2018-Sep-26 16:00 UTC
[PATCH 2/4] drm/virtio: Handle context ID allocation errors
It is possible to run out of memory while allocating IDs. The current code would create a context with an invalid ID; change it to return -ENOMEM to userspace. Signed-off-by: Matthew Wilcox <willy at infradead.org> --- drivers/gpu/drm/virtio/virtgpu_kms.c | 29 +++++++++++----------------- 1 file changed, 11 insertions(+), 18 deletions(-) diff --git a/drivers/gpu/drm/virtio/virtgpu_kms.c b/drivers/gpu/drm/virtio/virtgpu_kms.c index e2604fe1b4ae..bf609dcae224 100644 --- a/drivers/gpu/drm/virtio/virtgpu_kms.c +++ b/drivers/gpu/drm/virtio/virtgpu_kms.c @@ -52,31 +52,22 @@ static void virtio_gpu_config_changed_work_func(struct work_struct *work) events_clear, &events_clear); } -static void virtio_gpu_ctx_id_get(struct virtio_gpu_device *vgdev, - uint32_t *resid) +static int virtio_gpu_context_create(struct virtio_gpu_device *vgdev, + uint32_t nlen, const char *name) { int handle = ida_alloc_min(&vgdev->ctx_id_ida, 1, GFP_KERNEL); - *resid = handle; -} -static void virtio_gpu_ctx_id_put(struct virtio_gpu_device *vgdev, uint32_t id) -{ - ida_free(&vgdev->ctx_id_ida, id); -} - -static void virtio_gpu_context_create(struct virtio_gpu_device *vgdev, - uint32_t nlen, const char *name, - uint32_t *ctx_id) -{ - virtio_gpu_ctx_id_get(vgdev, ctx_id); - virtio_gpu_cmd_context_create(vgdev, *ctx_id, nlen, name); + if (handle < 0) + return handle; + virtio_gpu_cmd_context_create(vgdev, handle, nlen, name); + return handle; } static void virtio_gpu_context_destroy(struct virtio_gpu_device *vgdev, uint32_t ctx_id) { virtio_gpu_cmd_context_destroy(vgdev, ctx_id); - virtio_gpu_ctx_id_put(vgdev, ctx_id); + ida_free(&vgdev->ctx_id_ida, ctx_id); } static void virtio_gpu_init_vq(struct virtio_gpu_queue *vgvq, @@ -261,7 +252,7 @@ int virtio_gpu_driver_open(struct drm_device *dev, struct drm_file *file) { struct virtio_gpu_device *vgdev = dev->dev_private; struct virtio_gpu_fpriv *vfpriv; - uint32_t id; + int id; char dbgname[TASK_COMM_LEN]; /* can't create contexts without 3d renderer */ @@ -274,7 +265,9 @@ int virtio_gpu_driver_open(struct drm_device *dev, struct drm_file *file) return -ENOMEM; get_task_comm(dbgname, current); - virtio_gpu_context_create(vgdev, strlen(dbgname), dbgname, &id); + id = virtio_gpu_context_create(vgdev, strlen(dbgname), dbgname); + if (id < 0) + return id; vfpriv->ctx_id = id; file->driver_priv = vfpriv; -- 2.19.0
Matthew Wilcox
2018-Sep-26 16:00 UTC
[PATCH 3/4] drm/virtio: Handle object ID allocation errors
It is possible to run out of memory while allocating IDs. The current code would create an object with an invalid ID; change it to return -ENOMEM to the caller. Signed-off-by: Matthew Wilcox <willy at infradead.org> --- drivers/gpu/drm/virtio/virtgpu_drv.h | 3 +-- drivers/gpu/drm/virtio/virtgpu_fb.c | 10 ++++++++-- drivers/gpu/drm/virtio/virtgpu_gem.c | 10 ++++++++-- drivers/gpu/drm/virtio/virtgpu_ioctl.c | 5 ++++- drivers/gpu/drm/virtio/virtgpu_vq.c | 6 ++---- 5 files changed, 23 insertions(+), 11 deletions(-) diff --git a/drivers/gpu/drm/virtio/virtgpu_drv.h b/drivers/gpu/drm/virtio/virtgpu_drv.h index c4468a4e454e..0a3392f2cda3 100644 --- a/drivers/gpu/drm/virtio/virtgpu_drv.h +++ b/drivers/gpu/drm/virtio/virtgpu_drv.h @@ -247,8 +247,7 @@ int virtio_gpu_surface_dirty(struct virtio_gpu_framebuffer *qfb, /* virtio vg */ int virtio_gpu_alloc_vbufs(struct virtio_gpu_device *vgdev); void virtio_gpu_free_vbufs(struct virtio_gpu_device *vgdev); -void virtio_gpu_resource_id_get(struct virtio_gpu_device *vgdev, - uint32_t *resid); +int virtio_gpu_resource_id_get(struct virtio_gpu_device *vgdev); void virtio_gpu_resource_id_put(struct virtio_gpu_device *vgdev, uint32_t id); void virtio_gpu_cmd_create_resource(struct virtio_gpu_device *vgdev, uint32_t resource_id, diff --git a/drivers/gpu/drm/virtio/virtgpu_fb.c b/drivers/gpu/drm/virtio/virtgpu_fb.c index a121b1c79522..74d815483487 100644 --- a/drivers/gpu/drm/virtio/virtgpu_fb.c +++ b/drivers/gpu/drm/virtio/virtgpu_fb.c @@ -244,14 +244,17 @@ static int virtio_gpufb_create(struct drm_fb_helper *helper, if (IS_ERR(obj)) return PTR_ERR(obj); - virtio_gpu_resource_id_get(vgdev, &resid); + ret = virtio_gpu_resource_id_get(vgdev); + if (ret < 0) + goto err_obj_vmap; + resid = ret; virtio_gpu_cmd_create_resource(vgdev, resid, format, mode_cmd.width, mode_cmd.height); ret = virtio_gpu_vmap_fb(vgdev, obj); if (ret) { DRM_ERROR("failed to vmap fb %d\n", ret); - goto err_obj_vmap; + goto err_obj_id; } /* attach the object to the resource */ @@ -293,8 +296,11 @@ static int virtio_gpufb_create(struct drm_fb_helper *helper, err_fb_alloc: virtio_gpu_cmd_resource_inval_backing(vgdev, resid); err_obj_attach: +err_obj_id: + virtio_gpu_resource_id_put(vgdev, resid); err_obj_vmap: virtio_gpu_gem_free_object(&obj->gem_base); + return ret; } diff --git a/drivers/gpu/drm/virtio/virtgpu_gem.c b/drivers/gpu/drm/virtio/virtgpu_gem.c index 0f2768eacaee..9e3af1ec26db 100644 --- a/drivers/gpu/drm/virtio/virtgpu_gem.c +++ b/drivers/gpu/drm/virtio/virtgpu_gem.c @@ -100,7 +100,10 @@ int virtio_gpu_mode_dumb_create(struct drm_file *file_priv, goto fail; format = virtio_gpu_translate_format(DRM_FORMAT_XRGB8888); - virtio_gpu_resource_id_get(vgdev, &resid); + ret = virtio_gpu_resource_id_get(vgdev); + if (ret < 0) + goto fail; + resid = ret; virtio_gpu_cmd_create_resource(vgdev, resid, format, args->width, args->height); @@ -108,13 +111,16 @@ int virtio_gpu_mode_dumb_create(struct drm_file *file_priv, obj = gem_to_virtio_gpu_obj(gobj); ret = virtio_gpu_object_attach(vgdev, obj, resid, NULL); if (ret) - goto fail; + goto fail_id; obj->dumb = true; args->pitch = pitch; return ret; +fail_id: + virtio_gpu_resource_id_put(vgdev, resid); fail: + /* Shouldn't we undo virtio_gpu_gem_create()? */ return ret; } diff --git a/drivers/gpu/drm/virtio/virtgpu_ioctl.c b/drivers/gpu/drm/virtio/virtgpu_ioctl.c index 7bdf6f0e58a5..eec9f09f01f0 100644 --- a/drivers/gpu/drm/virtio/virtgpu_ioctl.c +++ b/drivers/gpu/drm/virtio/virtgpu_ioctl.c @@ -244,7 +244,10 @@ static int virtio_gpu_resource_create_ioctl(struct drm_device *dev, void *data, INIT_LIST_HEAD(&validate_list); memset(&mainbuf, 0, sizeof(struct ttm_validate_buffer)); - virtio_gpu_resource_id_get(vgdev, &res_id); + ret = virtio_gpu_resource_id_get(vgdev); + if (ret < 0) + return ret; + res_id = ret; size = rc->size; diff --git a/drivers/gpu/drm/virtio/virtgpu_vq.c b/drivers/gpu/drm/virtio/virtgpu_vq.c index 58be09d2eed6..387951c971d4 100644 --- a/drivers/gpu/drm/virtio/virtgpu_vq.c +++ b/drivers/gpu/drm/virtio/virtgpu_vq.c @@ -38,11 +38,9 @@ + MAX_INLINE_CMD_SIZE \ + MAX_INLINE_RESP_SIZE) -void virtio_gpu_resource_id_get(struct virtio_gpu_device *vgdev, - uint32_t *resid) +int virtio_gpu_resource_id_get(struct virtio_gpu_device *vgdev) { - int handle = ida_alloc_min(&vgdev->resource_ida, 1, GFP_KERNEL); - *resid = handle; + return ida_alloc_min(&vgdev->resource_ida, 1, GFP_KERNEL); } void virtio_gpu_resource_id_put(struct virtio_gpu_device *vgdev, uint32_t id) -- 2.19.0
0-based IDAs are more efficient than any other base. Convert the 1-based IDAs to be 0-based. Signed-off-by: Matthew Wilcox <willy at infradead.org> --- drivers/gpu/drm/virtio/virtgpu_kms.c | 3 ++- drivers/gpu/drm/virtio/virtgpu_vq.c | 7 +++++-- 2 files changed, 7 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/virtio/virtgpu_kms.c b/drivers/gpu/drm/virtio/virtgpu_kms.c index bf609dcae224..b576c9ef6323 100644 --- a/drivers/gpu/drm/virtio/virtgpu_kms.c +++ b/drivers/gpu/drm/virtio/virtgpu_kms.c @@ -59,6 +59,7 @@ static int virtio_gpu_context_create(struct virtio_gpu_device *vgdev, if (handle < 0) return handle; + handle++; virtio_gpu_cmd_context_create(vgdev, handle, nlen, name); return handle; } @@ -67,7 +68,7 @@ static void virtio_gpu_context_destroy(struct virtio_gpu_device *vgdev, uint32_t ctx_id) { virtio_gpu_cmd_context_destroy(vgdev, ctx_id); - ida_free(&vgdev->ctx_id_ida, ctx_id); + ida_free(&vgdev->ctx_id_ida, ctx_id - 1); } static void virtio_gpu_init_vq(struct virtio_gpu_queue *vgvq, diff --git a/drivers/gpu/drm/virtio/virtgpu_vq.c b/drivers/gpu/drm/virtio/virtgpu_vq.c index 387951c971d4..81297fe0147d 100644 --- a/drivers/gpu/drm/virtio/virtgpu_vq.c +++ b/drivers/gpu/drm/virtio/virtgpu_vq.c @@ -40,12 +40,15 @@ int virtio_gpu_resource_id_get(struct virtio_gpu_device *vgdev) { - return ida_alloc_min(&vgdev->resource_ida, 1, GFP_KERNEL); + int handle = ida_alloc(&vgdev->resource_ida, GFP_KERNEL); + if (handle < 0) + return handle; + return handle + 1; } void virtio_gpu_resource_id_put(struct virtio_gpu_device *vgdev, uint32_t id) { - ida_free(&vgdev->resource_ida, id); + ida_free(&vgdev->resource_ida, id - 1); } void virtio_gpu_ctrl_ack(struct virtqueue *vq) -- 2.19.0
On Wed, Sep 26, 2018 at 09:00:31AM -0700, Matthew Wilcox wrote:> @@ -59,6 +59,7 @@ static int virtio_gpu_context_create(struct virtio_gpu_device *vgdev, > > if (handle < 0) > return handle; > + handle++; > virtio_gpu_cmd_context_create(vgdev, handle, nlen, name); > return handle; > }Uh. This line is missing. - int handle = ida_alloc_min(&vgdev->ctx_id_ida, 1, GFP_KERNEL); + int handle = ida_alloc(&vgdev->ctx_id_ida, GFP_KERNEL); It'll be there in v2 ;-)