Hi Binoy, Looks good to me. However (and maybe Jiri can amend this while applying the patch), the title still says "HID: Replace semaphore driver_lock with mutex" while you killed it altogether...
Cheers, Benjamin On Jun 14 2017 or thereabouts, Binoy Jayan wrote: > The semaphore 'driver_lock' is used as a simple mutex, and > also unnecessary as suggested by Arnd. Hence removing it, as > the concurrency between the probe and remove is already > handled in the driver core. > > Suggested-by: Arnd Bergmann <[email protected]> > Signed-off-by: Binoy Jayan <[email protected]> > Acked-by: Benjamin Tissoires <[email protected]> > Reviewed-by: David Herrmann <[email protected]> > --- > > v2 --> v3: > Removed reference to driver_lock in comments > > v1 --> v2: > Removed driver_lock > > drivers/hid/hid-core.c | 15 ++++----------- > include/linux/hid.h | 3 +-- > 2 files changed, 5 insertions(+), 13 deletions(-) > > diff --git a/drivers/hid/hid-core.c b/drivers/hid/hid-core.c > index 04cee65..559533b 100644 > --- a/drivers/hid/hid-core.c > +++ b/drivers/hid/hid-core.c > @@ -2225,11 +2225,9 @@ static int hid_device_probe(struct device *dev) > const struct hid_device_id *id; > int ret = 0; > > - if (down_interruptible(&hdev->driver_lock)) > - return -EINTR; > if (down_interruptible(&hdev->driver_input_lock)) { > ret = -EINTR; > - goto unlock_driver_lock; > + goto end; > } > hdev->io_started = false; > > @@ -2256,8 +2254,7 @@ static int hid_device_probe(struct device *dev) > unlock: > if (!hdev->io_started) > up(&hdev->driver_input_lock); > -unlock_driver_lock: > - up(&hdev->driver_lock); > +end: > return ret; > } > > @@ -2267,11 +2264,9 @@ static int hid_device_remove(struct device *dev) > struct hid_driver *hdrv; > int ret = 0; > > - if (down_interruptible(&hdev->driver_lock)) > - return -EINTR; > if (down_interruptible(&hdev->driver_input_lock)) { > ret = -EINTR; > - goto unlock_driver_lock; > + goto end; > } > hdev->io_started = false; > > @@ -2287,8 +2282,7 @@ static int hid_device_remove(struct device *dev) > > if (!hdev->io_started) > up(&hdev->driver_input_lock); > -unlock_driver_lock: > - up(&hdev->driver_lock); > +end: > return ret; > } > > @@ -2745,7 +2739,6 @@ struct hid_device *hid_allocate_device(void) > init_waitqueue_head(&hdev->debug_wait); > INIT_LIST_HEAD(&hdev->debug_list); > spin_lock_init(&hdev->debug_list_lock); > - sema_init(&hdev->driver_lock, 1); > sema_init(&hdev->driver_input_lock, 1); > > return hdev; > diff --git a/include/linux/hid.h b/include/linux/hid.h > index 5be325d..a49203f 100644 > --- a/include/linux/hid.h > +++ b/include/linux/hid.h > @@ -516,7 +516,6 @@ struct hid_device { > /* device report descriptor */ > struct hid_report_enum report_enum[HID_REPORT_TYPES]; > struct work_struct led_work; /* > delayed LED worker */ > > - struct semaphore driver_lock; /* > protects the current driver, except during input */ > struct semaphore driver_input_lock; /* > protects the current driver */ > struct device dev; /* > device */ > struct hid_driver *driver; > @@ -538,7 +537,7 @@ struct hid_device { > /* device report descriptor */ > unsigned int status; /* see > STAT flags above */ > unsigned claimed; /* > Claimed by hidinput, hiddev? */ > unsigned quirks; /* > Various quirks the device can pull on us */ > - bool io_started; /* > Protected by driver_lock. If IO has started */ > + bool io_started; /* If > IO has started */ > > struct list_head inputs; /* The > list of inputs */ > void *hiddev; /* The > hiddev structure */ > -- > Binoy Jayan >
