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 ;-)
Apparently Analagous Threads
- [PATCH 0/4] Improve virtio ID allocation
- [PATCH 4/4] drm/virtio: Use IDAs more efficiently
- [PATCH 4/4] drm/virtio: Use IDAs more efficiently
- [PATCH 4/4] drm/virtio: Use IDAs more efficiently
- [PATCH] drm/virtio: make resource id workaround runtime switchable.