| Message ID | 20240223-iio-use-cleanup-magic-v2-1-f6b4848c1f34@analog.com (mailing list archive) |
|---|---|
| State | Changes Requested |
| Headers | show |
| Series | iio: move IIO to the cleanup.h magic | expand |
On Fri, 23 Feb 2024 13:43:44 +0100 Nuno Sa <nuno.sa@analog.com> wrote: > Use the new cleanup magic for handling mutexes in IIO. This allows us to > greatly simplify some code paths. > > Note that we keep the plain mutex calls in the > iio_device_release|acquire() APIs since in there the macros would likely > not help much (as we want to keep the lock acquired when he leave the > APIs). > > Signed-off-by: Nuno Sa <nuno.sa@analog.com> > --- > @@ -1808,29 +1805,22 @@ static long iio_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) > struct iio_ioctl_handler *h; > int ret = -ENODEV; > > - mutex_lock(&iio_dev_opaque->info_exist_lock); > - > + guard(mutex)(&iio_dev_opaque->info_exist_lock); > /* > * The NULL check here is required to prevent crashing when a device > * is being removed while userspace would still have open file handles > * to try to access this device. > */ > if (!indio_dev->info) > - goto out_unlock; > + return ret; return -ENODEV; and drop initialisation above. > > list_for_each_entry(h, &iio_dev_opaque->ioctl_handlers, entry) { > ret = h->ioctl(indio_dev, filp, cmd, arg); > if (ret != IIO_IOCTL_UNHANDLED) > - break; > + return ret; > } > > - if (ret == IIO_IOCTL_UNHANDLED) > - ret = -ENODEV; > - > -out_unlock: > - mutex_unlock(&iio_dev_opaque->info_exist_lock); > - > - return ret; > + return -ENODEV; > }
On Sun, 2024-02-25 at 12:36 +0000, Jonathan Cameron wrote: > On Fri, 23 Feb 2024 13:43:44 +0100 > Nuno Sa <nuno.sa@analog.com> wrote: > > > Use the new cleanup magic for handling mutexes in IIO. This allows us to > > greatly simplify some code paths. > > > > Note that we keep the plain mutex calls in the > > iio_device_release|acquire() APIs since in there the macros would likely > > not help much (as we want to keep the lock acquired when he leave the > > APIs). > > > > Signed-off-by: Nuno Sa <nuno.sa@analog.com> > > --- > > > > @@ -1808,29 +1805,22 @@ static long iio_ioctl(struct file *filp, unsigned int > > cmd, unsigned long arg) > > struct iio_ioctl_handler *h; > > int ret = -ENODEV; > > > > - mutex_lock(&iio_dev_opaque->info_exist_lock); > > - > > + guard(mutex)(&iio_dev_opaque->info_exist_lock); > > /* > > * The NULL check here is required to prevent crashing when a device > > * is being removed while userspace would still have open file handles > > * to try to access this device. > > */ > > if (!indio_dev->info) > > - goto out_unlock; > > + return ret; > > return -ENODEV; and drop initialisation above. Ok, that was actually what I had. Ended up changing it because of the slightly smaller diff on the patch. - Nuno Sá
diff --git a/drivers/iio/industrialio-core.c b/drivers/iio/industrialio-core.c index 9b2877fe8689..17cc3e579d56 100644 --- a/drivers/iio/industrialio-core.c +++ b/drivers/iio/industrialio-core.c @@ -11,6 +11,7 @@ #include <linux/anon_inodes.h> #include <linux/cdev.h> +#include <linux/cleanup.h> #include <linux/debugfs.h> #include <linux/device.h> #include <linux/err.h> @@ -268,20 +269,16 @@ EXPORT_SYMBOL(iio_read_const_attr); */ int iio_device_set_clock(struct iio_dev *indio_dev, clockid_t clock_id) { - int ret; struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(indio_dev); const struct iio_event_interface *ev_int = iio_dev_opaque->event_interface; - ret = mutex_lock_interruptible(&iio_dev_opaque->mlock); - if (ret) - return ret; - if ((ev_int && iio_event_enabled(ev_int)) || - iio_buffer_enabled(indio_dev)) { - mutex_unlock(&iio_dev_opaque->mlock); - return -EBUSY; + scoped_cond_guard(mutex_intr, return -EINTR, &iio_dev_opaque->mlock) { + if ((ev_int && iio_event_enabled(ev_int)) || + iio_buffer_enabled(indio_dev)) + return -EBUSY; + + iio_dev_opaque->clock_id = clock_id; } - iio_dev_opaque->clock_id = clock_id; - mutex_unlock(&iio_dev_opaque->mlock); return 0; } @@ -1808,29 +1805,22 @@ static long iio_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) struct iio_ioctl_handler *h; int ret = -ENODEV; - mutex_lock(&iio_dev_opaque->info_exist_lock); - + guard(mutex)(&iio_dev_opaque->info_exist_lock); /* * The NULL check here is required to prevent crashing when a device * is being removed while userspace would still have open file handles * to try to access this device. */ if (!indio_dev->info) - goto out_unlock; + return ret; list_for_each_entry(h, &iio_dev_opaque->ioctl_handlers, entry) { ret = h->ioctl(indio_dev, filp, cmd, arg); if (ret != IIO_IOCTL_UNHANDLED) - break; + return ret; } - if (ret == IIO_IOCTL_UNHANDLED) - ret = -ENODEV; - -out_unlock: - mutex_unlock(&iio_dev_opaque->info_exist_lock); - - return ret; + return -ENODEV; } static const struct file_operations iio_buffer_fileops = { @@ -2058,18 +2048,16 @@ void iio_device_unregister(struct iio_dev *indio_dev) cdev_device_del(&iio_dev_opaque->chrdev, &indio_dev->dev); - mutex_lock(&iio_dev_opaque->info_exist_lock); + scoped_guard(mutex, &iio_dev_opaque->info_exist_lock) { + iio_device_unregister_debugfs(indio_dev); - iio_device_unregister_debugfs(indio_dev); + iio_disable_all_buffers(indio_dev); - iio_disable_all_buffers(indio_dev); + indio_dev->info = NULL; - indio_dev->info = NULL; - - iio_device_wakeup_eventset(indio_dev); - iio_buffer_wakeup_poll(indio_dev); - - mutex_unlock(&iio_dev_opaque->info_exist_lock); + iio_device_wakeup_eventset(indio_dev); + iio_buffer_wakeup_poll(indio_dev); + } iio_buffers_free_sysfs_and_mask(indio_dev); }
Use the new cleanup magic for handling mutexes in IIO. This allows us to greatly simplify some code paths. Note that we keep the plain mutex calls in the iio_device_release|acquire() APIs since in there the macros would likely not help much (as we want to keep the lock acquired when he leave the APIs). Signed-off-by: Nuno Sa <nuno.sa@analog.com> --- drivers/iio/industrialio-core.c | 48 ++++++++++++++++------------------------- 1 file changed, 18 insertions(+), 30 deletions(-)