[Public]
> -----Original Message-----
> From: Meng, Li (Jassmine) <li.m...@amd.com>
> Sent: Monday, June 23, 2025 9:53 PM
> To: amd-gfx <amd-gfx@lists.freedesktop.org>
> Cc: Yuan, Perry <perry.y...@amd.com>; Huang, Shimmer
> <shimmer.hu...@amd.com>; Koenig Christian <koenig.christ...@amd.com>;
> Lazar, Lijo <lijo.la...@amd.com>; Deucher, Alexander
> <alexander.deuc...@amd.com>; Meng, Li (Jassmine) <li.m...@amd.com>;
> Jiang Liu <ge...@linux.alibaba.com>
> Subject: [PATCH V3 1/1] drm/amd/amdgpu: Release xcp drm memory after unplug
>
> Add a new API amdgpu_xcp_drm_dev_free().
> After unplug xcp device, need to release xcp drm memory etc.
>
> Co-developed-by: Jiang Liu <ge...@linux.alibaba.com>
> Signed-off-by: Jiang Liu <ge...@linux.alibaba.com>
> Signed-off-by: Meng Li <li.m...@amd.com>
> ---
> drivers/gpu/drm/amd/amdgpu/amdgpu_xcp.c | 1 +
> drivers/gpu/drm/amd/amdxcp/amdgpu_xcp_drv.c | 60 +++++++++++++++++----
> drivers/gpu/drm/amd/amdxcp/amdgpu_xcp_drv.h | 1 +
> 3 files changed, 53 insertions(+), 9 deletions(-)
>
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_xcp.c
> b/drivers/gpu/drm/amd/amdgpu/amdgpu_xcp.c
> index 322816805bfb..70c44961af95 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_xcp.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_xcp.c
> @@ -394,6 +394,7 @@ void amdgpu_xcp_dev_unplug(struct amdgpu_device
> *adev)
> p_ddev->primary->dev = adev->xcp_mgr->xcp[i].pdev;
> p_ddev->driver = adev->xcp_mgr->xcp[i].driver;
> p_ddev->vma_offset_manager = adev->xcp_mgr-
> >xcp[i].vma_offset_manager;
> + amdgpu_xcp_drm_dev_free(p_ddev);
> }
> }
>
> diff --git a/drivers/gpu/drm/amd/amdxcp/amdgpu_xcp_drv.c
> b/drivers/gpu/drm/amd/amdxcp/amdgpu_xcp_drv.c
> index faed84172dd4..3a8f3dd19a12 100644
> --- a/drivers/gpu/drm/amd/amdxcp/amdgpu_xcp_drv.c
> +++ b/drivers/gpu/drm/amd/amdxcp/amdgpu_xcp_drv.c
> @@ -45,18 +45,29 @@ static const struct drm_driver amdgpu_xcp_driver = {
>
> static int8_t pdev_num;
> static struct xcp_device *xcp_dev[MAX_XCP_PLATFORM_DEVICE];
> +static DEFINE_MUTEX(xcp_mutex);
>
> int amdgpu_xcp_drm_dev_alloc(struct drm_device **ddev) {
> struct platform_device *pdev;
> struct xcp_device *pxcp_dev;
> char dev_name[20];
> - int ret;
> + int ret, i;
> +
> + guard(mutex)(&xcp_mutex);
>
> if (pdev_num >= MAX_XCP_PLATFORM_DEVICE)
> return -ENODEV;
>
> - snprintf(dev_name, sizeof(dev_name), "amdgpu_xcp_%d", pdev_num);
> + for (i = 0; i < MAX_XCP_PLATFORM_DEVICE; i++) {
> + if (!xcp_dev[i])
> + break;
> + }
> +
> + if (i >= MAX_XCP_PLATFORM_DEVICE)
> + return -ENODEV;
> +
> + snprintf(dev_name, sizeof(dev_name), "amdgpu_xcp_%d", i);
> pdev = platform_device_register_simple(dev_name, -1, NULL, 0);
> if (IS_ERR(pdev))
> return PTR_ERR(pdev);
> @@ -72,8 +83,8 @@ int amdgpu_xcp_drm_dev_alloc(struct drm_device **ddev)
> goto out_devres;
> }
>
> - xcp_dev[pdev_num] = pxcp_dev;
> - xcp_dev[pdev_num]->pdev = pdev;
> + xcp_dev[i] = pxcp_dev;
> + xcp_dev[i]->pdev = pdev;
> *ddev = &pxcp_dev->drm;
> pdev_num++;
>
> @@ -88,16 +99,47 @@ int amdgpu_xcp_drm_dev_alloc(struct drm_device **ddev)
> } EXPORT_SYMBOL(amdgpu_xcp_drm_dev_alloc);
>
> -void amdgpu_xcp_drv_release(void)
> +static void free_xcp_dev(int8_t index)
> {
> - for (--pdev_num; pdev_num >= 0; --pdev_num) {
> - struct platform_device *pdev = xcp_dev[pdev_num]->pdev;
> + if ((index < MAX_XCP_PLATFORM_DEVICE) && (xcp_dev[index])) {
> + struct platform_device *pdev = xcp_dev[index]->pdev;
>
> devres_release_group(&pdev->dev, NULL);
> platform_device_unregister(pdev);
> - xcp_dev[pdev_num] = NULL;
> +
> + xcp_dev[index] = NULL;
> + pdev_num--;
> + }
> +}
> +
> +void amdgpu_xcp_drm_dev_free(struct drm_device *ddev) {
> + int8_t i = MAX_XCP_PLATFORM_DEVICE;
No need to init i here. You aren't using the assigned value. With that fixed:
Acked-by: Alex Deucher <alexander.deuc...@amd.com>
> +
> + guard(mutex)(&xcp_mutex);
> +
> + for (i = 0; i < MAX_XCP_PLATFORM_DEVICE; i++) {
> + if ((xcp_dev[i]) && (&xcp_dev[i]->drm == ddev)) {
> + free_xcp_dev(i);
> + break;
> + }
> + }
> +}
> +EXPORT_SYMBOL(amdgpu_xcp_drm_dev_free);
> +
> +void amdgpu_xcp_drv_release(void)
> +{
> + int8_t i = 0;
> +
> + guard(mutex)(&xcp_mutex);
> +
> + if (pdev_num > 0) {
> + for (i = 0; i < MAX_XCP_PLATFORM_DEVICE; i++) {
> + free_xcp_dev(i);
> + if (pdev_num == 0)
> + break;
> + }
> }
> - pdev_num = 0;
> }
> EXPORT_SYMBOL(amdgpu_xcp_drv_release);
>
> diff --git a/drivers/gpu/drm/amd/amdxcp/amdgpu_xcp_drv.h
> b/drivers/gpu/drm/amd/amdxcp/amdgpu_xcp_drv.h
> index c1c4b679bf95..580a1602c8e3 100644
> --- a/drivers/gpu/drm/amd/amdxcp/amdgpu_xcp_drv.h
> +++ b/drivers/gpu/drm/amd/amdxcp/amdgpu_xcp_drv.h
> @@ -25,5 +25,6 @@
> #define _AMDGPU_XCP_DRV_H_
>
> int amdgpu_xcp_drm_dev_alloc(struct drm_device **ddev);
> +void amdgpu_xcp_drm_dev_free(struct drm_device *ddev);
> void amdgpu_xcp_drv_release(void);
> #endif /* _AMDGPU_XCP_DRV_H_ */
> --
> 2.43.0
