| Message ID | 20190220210343.28157-6-eric@anholt.net (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [1/7] drm: Add a helper function for printing a debugfs_regset32. | expand |
Hi, Le mercredi 20 février 2019 à 13:03 -0800, Eric Anholt a écrit : > This makes sure the vc4_reset doesn't hit an obscure race with the > GET_PARAM ioctl, fixes a decrement outside of the lock, and prevents > future code from making mistakes with the weird return value of > pm_runtime_get_sync(). Reviewed-by: Paul Kocialkowski <paul.kocialkowski@bootlin.com> Cheers, Paul > Signed-off-by: Eric Anholt <eric@anholt.net> > --- > drivers/gpu/drm/vc4/vc4_drv.c | 21 +++++++++------------ > drivers/gpu/drm/vc4/vc4_drv.h | 2 ++ > drivers/gpu/drm/vc4/vc4_gem.c | 21 +++++---------------- > drivers/gpu/drm/vc4/vc4_v3d.c | 33 +++++++++++++++++++++++++++++++++ > 4 files changed, 49 insertions(+), 28 deletions(-) > > diff --git a/drivers/gpu/drm/vc4/vc4_drv.c b/drivers/gpu/drm/vc4/vc4_drv.c > index de1d0ce11831..f95891a61d52 100644 > --- a/drivers/gpu/drm/vc4/vc4_drv.c > +++ b/drivers/gpu/drm/vc4/vc4_drv.c > @@ -77,28 +77,25 @@ static int vc4_get_param_ioctl(struct drm_device *dev, void *data, > > switch (args->param) { > case DRM_VC4_PARAM_V3D_IDENT0: > - ret = pm_runtime_get_sync(&vc4->v3d->pdev->dev); > - if (ret < 0) > + ret = vc4_v3d_pm_get(vc4); > + if (ret) > return ret; > args->value = V3D_READ(V3D_IDENT0); > - pm_runtime_mark_last_busy(&vc4->v3d->pdev->dev); > - pm_runtime_put_autosuspend(&vc4->v3d->pdev->dev); > + vc4_v3d_pm_put(vc4); > break; > case DRM_VC4_PARAM_V3D_IDENT1: > - ret = pm_runtime_get_sync(&vc4->v3d->pdev->dev); > - if (ret < 0) > + ret = vc4_v3d_pm_get(vc4); > + if (ret) > return ret; > args->value = V3D_READ(V3D_IDENT1); > - pm_runtime_mark_last_busy(&vc4->v3d->pdev->dev); > - pm_runtime_put_autosuspend(&vc4->v3d->pdev->dev); > + vc4_v3d_pm_put(vc4); > break; > case DRM_VC4_PARAM_V3D_IDENT2: > - ret = pm_runtime_get_sync(&vc4->v3d->pdev->dev); > - if (ret < 0) > + ret = vc4_v3d_pm_get(vc4); > + if (ret) > return ret; > args->value = V3D_READ(V3D_IDENT2); > - pm_runtime_mark_last_busy(&vc4->v3d->pdev->dev); > - pm_runtime_put_autosuspend(&vc4->v3d->pdev->dev); > + vc4_v3d_pm_put(vc4); > break; > case DRM_VC4_PARAM_SUPPORTS_BRANCHES: > case DRM_VC4_PARAM_SUPPORTS_ETC1: > diff --git a/drivers/gpu/drm/vc4/vc4_drv.h b/drivers/gpu/drm/vc4/vc4_drv.h > index 495c5a13a948..c71988b270bc 100644 > --- a/drivers/gpu/drm/vc4/vc4_drv.h > +++ b/drivers/gpu/drm/vc4/vc4_drv.h > @@ -809,6 +809,8 @@ void vc4_plane_async_set_fb(struct drm_plane *plane, > /* vc4_v3d.c */ > extern struct platform_driver vc4_v3d_driver; > int vc4_v3d_get_bin_slot(struct vc4_dev *vc4); > +int vc4_v3d_pm_get(struct vc4_dev *vc4); > +void vc4_v3d_pm_put(struct vc4_dev *vc4); > > /* vc4_validate.c */ > int > diff --git a/drivers/gpu/drm/vc4/vc4_gem.c b/drivers/gpu/drm/vc4/vc4_gem.c > index 8d816e5ed762..4544a478f106 100644 > --- a/drivers/gpu/drm/vc4/vc4_gem.c > +++ b/drivers/gpu/drm/vc4/vc4_gem.c > @@ -969,12 +969,7 @@ vc4_complete_exec(struct drm_device *dev, struct vc4_exec_info *exec) > /* Release the reference we had on the perf monitor. */ > vc4_perfmon_put(exec->perfmon); > > - mutex_lock(&vc4->power_lock); > - if (--vc4->power_refcount == 0) { > - pm_runtime_mark_last_busy(&vc4->v3d->pdev->dev); > - pm_runtime_put_autosuspend(&vc4->v3d->pdev->dev); > - } > - mutex_unlock(&vc4->power_lock); > + vc4_v3d_pm_put(vc4); > > kfree(exec); > } > @@ -1153,17 +1148,11 @@ vc4_submit_cl_ioctl(struct drm_device *dev, void *data, > return -ENOMEM; > } > > - mutex_lock(&vc4->power_lock); > - if (vc4->power_refcount++ == 0) { > - ret = pm_runtime_get_sync(&vc4->v3d->pdev->dev); > - if (ret < 0) { > - mutex_unlock(&vc4->power_lock); > - vc4->power_refcount--; > - kfree(exec); > - return ret; > - } > + ret = vc4_v3d_pm_get(vc4); > + if (ret) { > + kfree(exec); > + return ret; > } > - mutex_unlock(&vc4->power_lock); > > exec->args = args; > INIT_LIST_HEAD(&exec->unref_list); > diff --git a/drivers/gpu/drm/vc4/vc4_v3d.c b/drivers/gpu/drm/vc4/vc4_v3d.c > index f008584eb739..7820b8eaaa98 100644 > --- a/drivers/gpu/drm/vc4/vc4_v3d.c > +++ b/drivers/gpu/drm/vc4/vc4_v3d.c > @@ -124,6 +124,39 @@ static int vc4_v3d_debugfs_ident(struct seq_file *m, void *unused) > return 0; > } > > +/** > + * Wraps pm_runtime_get_sync() in a refcount, so that we can reliably > + * get the pm_runtime refcount to 0 in vc4_reset(). > + */ > +int > +vc4_v3d_pm_get(struct vc4_dev *vc4) > +{ > + mutex_lock(&vc4->power_lock); > + if (vc4->power_refcount++ == 0) { > + int ret = pm_runtime_get_sync(&vc4->v3d->pdev->dev); > + > + if (ret < 0) { > + vc4->power_refcount--; > + mutex_unlock(&vc4->power_lock); > + return ret; > + } > + } > + mutex_unlock(&vc4->power_lock); > + > + return 0; > +} > + > +void > +vc4_v3d_pm_put(struct vc4_dev *vc4) > +{ > + mutex_lock(&vc4->power_lock); > + if (--vc4->power_refcount == 0) { > + pm_runtime_mark_last_busy(&vc4->v3d->pdev->dev); > + pm_runtime_put_autosuspend(&vc4->v3d->pdev->dev); > + } > + mutex_unlock(&vc4->power_lock); > +} > + > static void vc4_v3d_init_hw(struct drm_device *dev) > { > struct vc4_dev *vc4 = to_vc4_dev(dev);
diff --git a/drivers/gpu/drm/vc4/vc4_drv.c b/drivers/gpu/drm/vc4/vc4_drv.c index de1d0ce11831..f95891a61d52 100644 --- a/drivers/gpu/drm/vc4/vc4_drv.c +++ b/drivers/gpu/drm/vc4/vc4_drv.c @@ -77,28 +77,25 @@ static int vc4_get_param_ioctl(struct drm_device *dev, void *data, switch (args->param) { case DRM_VC4_PARAM_V3D_IDENT0: - ret = pm_runtime_get_sync(&vc4->v3d->pdev->dev); - if (ret < 0) + ret = vc4_v3d_pm_get(vc4); + if (ret) return ret; args->value = V3D_READ(V3D_IDENT0); - pm_runtime_mark_last_busy(&vc4->v3d->pdev->dev); - pm_runtime_put_autosuspend(&vc4->v3d->pdev->dev); + vc4_v3d_pm_put(vc4); break; case DRM_VC4_PARAM_V3D_IDENT1: - ret = pm_runtime_get_sync(&vc4->v3d->pdev->dev); - if (ret < 0) + ret = vc4_v3d_pm_get(vc4); + if (ret) return ret; args->value = V3D_READ(V3D_IDENT1); - pm_runtime_mark_last_busy(&vc4->v3d->pdev->dev); - pm_runtime_put_autosuspend(&vc4->v3d->pdev->dev); + vc4_v3d_pm_put(vc4); break; case DRM_VC4_PARAM_V3D_IDENT2: - ret = pm_runtime_get_sync(&vc4->v3d->pdev->dev); - if (ret < 0) + ret = vc4_v3d_pm_get(vc4); + if (ret) return ret; args->value = V3D_READ(V3D_IDENT2); - pm_runtime_mark_last_busy(&vc4->v3d->pdev->dev); - pm_runtime_put_autosuspend(&vc4->v3d->pdev->dev); + vc4_v3d_pm_put(vc4); break; case DRM_VC4_PARAM_SUPPORTS_BRANCHES: case DRM_VC4_PARAM_SUPPORTS_ETC1: diff --git a/drivers/gpu/drm/vc4/vc4_drv.h b/drivers/gpu/drm/vc4/vc4_drv.h index 495c5a13a948..c71988b270bc 100644 --- a/drivers/gpu/drm/vc4/vc4_drv.h +++ b/drivers/gpu/drm/vc4/vc4_drv.h @@ -809,6 +809,8 @@ void vc4_plane_async_set_fb(struct drm_plane *plane, /* vc4_v3d.c */ extern struct platform_driver vc4_v3d_driver; int vc4_v3d_get_bin_slot(struct vc4_dev *vc4); +int vc4_v3d_pm_get(struct vc4_dev *vc4); +void vc4_v3d_pm_put(struct vc4_dev *vc4); /* vc4_validate.c */ int diff --git a/drivers/gpu/drm/vc4/vc4_gem.c b/drivers/gpu/drm/vc4/vc4_gem.c index 8d816e5ed762..4544a478f106 100644 --- a/drivers/gpu/drm/vc4/vc4_gem.c +++ b/drivers/gpu/drm/vc4/vc4_gem.c @@ -969,12 +969,7 @@ vc4_complete_exec(struct drm_device *dev, struct vc4_exec_info *exec) /* Release the reference we had on the perf monitor. */ vc4_perfmon_put(exec->perfmon); - mutex_lock(&vc4->power_lock); - if (--vc4->power_refcount == 0) { - pm_runtime_mark_last_busy(&vc4->v3d->pdev->dev); - pm_runtime_put_autosuspend(&vc4->v3d->pdev->dev); - } - mutex_unlock(&vc4->power_lock); + vc4_v3d_pm_put(vc4); kfree(exec); } @@ -1153,17 +1148,11 @@ vc4_submit_cl_ioctl(struct drm_device *dev, void *data, return -ENOMEM; } - mutex_lock(&vc4->power_lock); - if (vc4->power_refcount++ == 0) { - ret = pm_runtime_get_sync(&vc4->v3d->pdev->dev); - if (ret < 0) { - mutex_unlock(&vc4->power_lock); - vc4->power_refcount--; - kfree(exec); - return ret; - } + ret = vc4_v3d_pm_get(vc4); + if (ret) { + kfree(exec); + return ret; } - mutex_unlock(&vc4->power_lock); exec->args = args; INIT_LIST_HEAD(&exec->unref_list); diff --git a/drivers/gpu/drm/vc4/vc4_v3d.c b/drivers/gpu/drm/vc4/vc4_v3d.c index f008584eb739..7820b8eaaa98 100644 --- a/drivers/gpu/drm/vc4/vc4_v3d.c +++ b/drivers/gpu/drm/vc4/vc4_v3d.c @@ -124,6 +124,39 @@ static int vc4_v3d_debugfs_ident(struct seq_file *m, void *unused) return 0; } +/** + * Wraps pm_runtime_get_sync() in a refcount, so that we can reliably + * get the pm_runtime refcount to 0 in vc4_reset(). + */ +int +vc4_v3d_pm_get(struct vc4_dev *vc4) +{ + mutex_lock(&vc4->power_lock); + if (vc4->power_refcount++ == 0) { + int ret = pm_runtime_get_sync(&vc4->v3d->pdev->dev); + + if (ret < 0) { + vc4->power_refcount--; + mutex_unlock(&vc4->power_lock); + return ret; + } + } + mutex_unlock(&vc4->power_lock); + + return 0; +} + +void +vc4_v3d_pm_put(struct vc4_dev *vc4) +{ + mutex_lock(&vc4->power_lock); + if (--vc4->power_refcount == 0) { + pm_runtime_mark_last_busy(&vc4->v3d->pdev->dev); + pm_runtime_put_autosuspend(&vc4->v3d->pdev->dev); + } + mutex_unlock(&vc4->power_lock); +} + static void vc4_v3d_init_hw(struct drm_device *dev) { struct vc4_dev *vc4 = to_vc4_dev(dev);
This makes sure the vc4_reset doesn't hit an obscure race with the GET_PARAM ioctl, fixes a decrement outside of the lock, and prevents future code from making mistakes with the weird return value of pm_runtime_get_sync(). Signed-off-by: Eric Anholt <eric@anholt.net> --- drivers/gpu/drm/vc4/vc4_drv.c | 21 +++++++++------------ drivers/gpu/drm/vc4/vc4_drv.h | 2 ++ drivers/gpu/drm/vc4/vc4_gem.c | 21 +++++---------------- drivers/gpu/drm/vc4/vc4_v3d.c | 33 +++++++++++++++++++++++++++++++++ 4 files changed, 49 insertions(+), 28 deletions(-)