On 2020-09-05 11:50, Alex Deucher wrote: > On Thu, Sep 3, 2020 at 9:22 PM Luben Tuikov <luben.tuikov@xxxxxxx> wrote: >> >> Convert to using devm_drm_dev_alloc(), >> as drm_dev_init() is going away. >> >> Signed-off-by: Luben Tuikov <luben.tuikov@xxxxxxx> > > I think we can drop the final drm_put in the error case? I think the > unwinding in current devm code should take care of it. We get to the error case if devm_drm_dev_alloc() succeeds, but we get an error thereafter, thus we do a drm_dev_put() past the err_free label, all in amdgpu_pci_probe(). However, devm_drm_dev_alloc() calls devm_drm_dev_init(), which calls drm_dev_init(), which does a kref_init() on &dev->ref, which sets the kref to 1. The drm_dev_put(), in the error case, would decrement it, and if it is 0 after being decremented, then drm_dev_release() is called, which does the "managed" free. Regards, Luben > > Alex > >> --- >> drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c | 11 +++-------- >> 1 file changed, 3 insertions(+), 8 deletions(-) >> >> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c >> index 146a85c8df1c..06d994187c24 100644 >> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c >> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c >> @@ -1142,18 +1142,13 @@ static int amdgpu_pci_probe(struct pci_dev *pdev, >> if (ret) >> return ret; >> >> - adev = kzalloc(sizeof(*adev), GFP_KERNEL); >> - if (!adev) >> - return -ENOMEM; >> + adev = devm_drm_dev_alloc(&pdev->dev, &kms_driver, typeof(*adev), ddev); >> + if (IS_ERR(adev)) >> + return PTR_ERR(adev); >> >> adev->dev = &pdev->dev; >> adev->pdev = pdev; >> ddev = adev_to_drm(adev); >> - ret = drm_dev_init(ddev, &kms_driver, &pdev->dev); >> - if (ret) >> - goto err_free; >> - >> - drmm_add_final_kfree(ddev, adev); >> >> if (!supports_atomic) >> ddev->driver_features &= ~DRIVER_ATOMIC; >> -- >> 2.28.0.394.ge197136389 >> >> _______________________________________________ >> amd-gfx mailing list >> amd-gfx@xxxxxxxxxxxxxxxxxxxxx >> https://nam11.safelinks.protection.outlook.com/?url=https%3A%2F%2Flists.freedesktop.org%2Fmailman%2Flistinfo%2Famd-gfx&data=02%7C01%7Cluben.tuikov%40amd.com%7C17ffbdbf1cfb4aa34d1c08d851b362cb%7C3dd8961fe4884e608e11a82d994e183d%7C0%7C0%7C637349178195046108&sdata=tSTqRZ27GuQVAP8g7jmXAmM%2BhiGn3RUa72flIapYp9c%3D&reserved=0 _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel
