Re: [PATCH v3 15/15] remoteproc: Refactor rproc delete and cdev release path
From: Mathieu Poirier
Date: Wed Dec 09 2020 - 16:35:09 EST
On Wed, Dec 09, 2020 at 11:13:07AM +0100, Arnaud POULIQUEN wrote:
>
>
> On 11/26/20 10:06 PM, Mathieu Poirier wrote:
> > Refactor function rproc_del() and rproc_cdev_release() to take
> > into account the policy specified in the device tree.
> >
> > Signed-off-by: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx>
> > ---
> > drivers/remoteproc/remoteproc_cdev.c | 13 +++++++++++-
> > drivers/remoteproc/remoteproc_core.c | 30 ++++++++++++++++++++++++++--
> > include/linux/remoteproc.h | 4 ++++
> > 3 files changed, 44 insertions(+), 3 deletions(-)
> >
> > diff --git a/drivers/remoteproc/remoteproc_cdev.c b/drivers/remoteproc/remoteproc_cdev.c
> > index f7645f289563..3dfe555dfc07 100644
> > --- a/drivers/remoteproc/remoteproc_cdev.c
> > +++ b/drivers/remoteproc/remoteproc_cdev.c
> > @@ -88,7 +88,18 @@ static int rproc_cdev_release(struct inode *inode, struct file *filp)
> > {
> > struct rproc *rproc = container_of(inode->i_cdev, struct rproc, cdev);
> >
> > - if (rproc->cdev_put_on_release && rproc->state == RPROC_RUNNING)
> > + if (!rproc->cdev_put_on_release)
> > + return 0;
> > +
> > + /*
> > + * The application has crashed or is releasing its file handle. Detach
> > + * or shutdown the remote processor based on the policy specified in the
> > + * DT. No need to check rproc->state right away, it will be done
> > + * in either rproc_detach() or rproc_shutdown().
> > + */
> > + if (rproc->autonomous_on_core_shutdown)
> > + rproc_detach(rproc);
> > + else
> > rproc_shutdown(rproc);
>
> A reason to not propagate the return of functions?
A valid observation... I'll fix it.
>
> >
> > return 0;
> > diff --git a/drivers/remoteproc/remoteproc_core.c b/drivers/remoteproc/remoteproc_core.c
> > index 3d7d245edc4e..1a170103bf27 100644
> > --- a/drivers/remoteproc/remoteproc_core.c
> > +++ b/drivers/remoteproc/remoteproc_core.c
> > @@ -2294,6 +2294,22 @@ static int rproc_alloc_ops(struct rproc *rproc, const struct rproc_ops *ops)
> > return 0;
> > }
> >
> > +static void rproc_set_automation_flags(struct rproc *rproc)
> > +{
> > + struct device *dev = rproc->dev.parent;
> > + struct device_node *np = dev->of_node;
> > + bool core_shutdown;
> > +
> > + /*
> > + * When function rproc_cdev_release() or rproc_del() are called and
> > + * the remote processor has been attached to, it will be detached from
> > + * (rather than turned off) if "autonomous-on-core-shutdown is specified
> > + * in the DT.
> > + */
> > + core_shutdown = of_property_read_bool(np, "autonomous-on-core-shutdown");
> > + rproc->autonomous_on_core_shutdown = core_shutdown;
> > +}
> > +
> > /**
> > * rproc_alloc() - allocate a remote processor handle
> > * @dev: the underlying device
> > @@ -2352,6 +2368,8 @@ struct rproc *rproc_alloc(struct device *dev, const char *name,
> > if (rproc_alloc_ops(rproc, ops))
> > goto put_device;
> >
> > + rproc_set_automation_flags(rproc);
> > +
> > /* Assign a unique device index and name */
> > rproc->index = ida_simple_get(&rproc_dev_index, 0, 0, GFP_KERNEL);
> > if (rproc->index < 0) {
> > @@ -2435,8 +2453,16 @@ int rproc_del(struct rproc *rproc)
> > if (!rproc)
> > return -EINVAL;
> >
> > - /* TODO: make sure this works with rproc->power > 1 */
> > - rproc_shutdown(rproc);
> > + /*
> > + * TODO: make sure this works with rproc->power > 1
> > + *
> > + * No need to check rproc->state right away, it will be done in either
> > + * rproc_detach() or rproc_shutdown().
> > + */
> > + if (rproc->autonomous_on_core_shutdown)
> > + rproc_detach(rproc);
> > + else
> > + rproc_shutdown(rproc);
>
> same here
>
> >
> > mutex_lock(&rproc->lock);
> > rproc->state = RPROC_DELETED;
> > diff --git a/include/linux/remoteproc.h b/include/linux/remoteproc.h
> > index 02312096d59f..5702f630d810 100644
> > --- a/include/linux/remoteproc.h
> > +++ b/include/linux/remoteproc.h
> > @@ -516,6 +516,9 @@ struct rproc_dump_segment {
> > * @nb_vdev: number of vdev currently handled by rproc
> > * @char_dev: character device of the rproc
> > * @cdev_put_on_release: flag to indicate if remoteproc should be shutdown on @char_dev release
> > + * @autonomous_on_core_shutdown: true if the remote processor should be detached
> > + * from (rather than turned off) when the remoteproc
> > + * core goes away.
> > */
> > struct rproc {
> > struct list_head node;
> > @@ -554,6 +557,7 @@ struct rproc {
> > u16 elf_machine;
> > struct cdev cdev;
> > bool cdev_put_on_release;
> > + bool autonomous_on_core_shutdown;
> > };
> >
> > /**
> >