| Message ID | 20200416123331.68790-1-alexandru.ardelean@analog.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | iio: core: fail early in iio_device_alloc() if we can't get a device id | expand |
On Thu, 16 Apr 2020 15:33:31 +0300 Alexandru Ardelean <alexandru.ardelean@analog.com> wrote: > This change moves the 'ida_simple_get()' call to be the first one in > iio_device_alloc(). It cleans up the error path a bit as we don't need to > call any kfree(dev) anymore. We allocate an IIO device only if we have > managed to obtain a device ID. We just threw away an ID if the kzalloc then fails (or am I missing something?) With that fixed I can't see this as being much of an improvement. Either way one allocation needs to be tidied up. Jonathan > > Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com> > --- > drivers/iio/industrialio-core.c | 19 ++++++++++--------- > 1 file changed, 10 insertions(+), 9 deletions(-) > > diff --git a/drivers/iio/industrialio-core.c b/drivers/iio/industrialio-core.c > index f4daf19f2a3b..7c1d8a3ab2f3 100644 > --- a/drivers/iio/industrialio-core.c > +++ b/drivers/iio/industrialio-core.c > @@ -1494,6 +1494,14 @@ struct iio_dev *iio_device_alloc(int sizeof_priv) > { > struct iio_dev *dev; > size_t alloc_size; > + int id; > + > + id = ida_simple_get(&iio_ida, 0, 0, GFP_KERNEL); > + if (id < 0) { > + /* cannot use a dev_err as the name isn't available */ > + pr_err("failed to get device id\n"); > + return NULL; > + } > > alloc_size = sizeof(struct iio_dev); > if (sizeof_priv) { > @@ -1506,6 +1514,8 @@ struct iio_dev *iio_device_alloc(int sizeof_priv) > dev = kzalloc(alloc_size, GFP_KERNEL); > > if (dev) { > + dev->id = id; > + dev_set_name(&dev->dev, "iio:device%d", dev->id); > dev->dev.groups = dev->groups; > dev->dev.type = &iio_device_type; > dev->dev.bus = &iio_bus_type; > @@ -1514,15 +1524,6 @@ struct iio_dev *iio_device_alloc(int sizeof_priv) > mutex_init(&dev->mlock); > mutex_init(&dev->info_exist_lock); > INIT_LIST_HEAD(&dev->channel_attr_list); > - > - dev->id = ida_simple_get(&iio_ida, 0, 0, GFP_KERNEL); > - if (dev->id < 0) { > - /* cannot use a dev_err as the name isn't available */ > - pr_err("failed to get device id\n"); > - kfree(dev); > - return NULL; > - } > - dev_set_name(&dev->dev, "iio:device%d", dev->id); > INIT_LIST_HEAD(&dev->buffer_list); > } >
On Sat, 2020-04-18 at 16:25 +0100, Jonathan Cameron wrote: > [External] > > On Thu, 16 Apr 2020 15:33:31 +0300 > Alexandru Ardelean <alexandru.ardelean@analog.com> wrote: > > > This change moves the 'ida_simple_get()' call to be the first one in > > iio_device_alloc(). It cleans up the error path a bit as we don't need to > > call any kfree(dev) anymore. We allocate an IIO device only if we have > > managed to obtain a device ID. > > We just threw away an ID if the kzalloc then fails (or am I missing > something?) > With that fixed I can't see this as being much of an improvement. > Either way one allocation needs to be tidied up. oops, the ida thingi eluded me when i wrote this; apologies for the noise > > Jonathan > > > Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com> > > --- > > drivers/iio/industrialio-core.c | 19 ++++++++++--------- > > 1 file changed, 10 insertions(+), 9 deletions(-) > > > > diff --git a/drivers/iio/industrialio-core.c b/drivers/iio/industrialio- > > core.c > > index f4daf19f2a3b..7c1d8a3ab2f3 100644 > > --- a/drivers/iio/industrialio-core.c > > +++ b/drivers/iio/industrialio-core.c > > @@ -1494,6 +1494,14 @@ struct iio_dev *iio_device_alloc(int sizeof_priv) > > { > > struct iio_dev *dev; > > size_t alloc_size; > > + int id; > > + > > + id = ida_simple_get(&iio_ida, 0, 0, GFP_KERNEL); > > + if (id < 0) { > > + /* cannot use a dev_err as the name isn't available */ > > + pr_err("failed to get device id\n"); > > + return NULL; > > + } > > > > alloc_size = sizeof(struct iio_dev); > > if (sizeof_priv) { > > @@ -1506,6 +1514,8 @@ struct iio_dev *iio_device_alloc(int sizeof_priv) > > dev = kzalloc(alloc_size, GFP_KERNEL); > > > > if (dev) { > > + dev->id = id; > > + dev_set_name(&dev->dev, "iio:device%d", dev->id); > > dev->dev.groups = dev->groups; > > dev->dev.type = &iio_device_type; > > dev->dev.bus = &iio_bus_type; > > @@ -1514,15 +1524,6 @@ struct iio_dev *iio_device_alloc(int sizeof_priv) > > mutex_init(&dev->mlock); > > mutex_init(&dev->info_exist_lock); > > INIT_LIST_HEAD(&dev->channel_attr_list); > > - > > - dev->id = ida_simple_get(&iio_ida, 0, 0, GFP_KERNEL); > > - if (dev->id < 0) { > > - /* cannot use a dev_err as the name isn't available */ > > - pr_err("failed to get device id\n"); > > - kfree(dev); > > - return NULL; > > - } > > - dev_set_name(&dev->dev, "iio:device%d", dev->id); > > INIT_LIST_HEAD(&dev->buffer_list); > > } > >
diff --git a/drivers/iio/industrialio-core.c b/drivers/iio/industrialio-core.c index f4daf19f2a3b..7c1d8a3ab2f3 100644 --- a/drivers/iio/industrialio-core.c +++ b/drivers/iio/industrialio-core.c @@ -1494,6 +1494,14 @@ struct iio_dev *iio_device_alloc(int sizeof_priv) { struct iio_dev *dev; size_t alloc_size; + int id; + + id = ida_simple_get(&iio_ida, 0, 0, GFP_KERNEL); + if (id < 0) { + /* cannot use a dev_err as the name isn't available */ + pr_err("failed to get device id\n"); + return NULL; + } alloc_size = sizeof(struct iio_dev); if (sizeof_priv) { @@ -1506,6 +1514,8 @@ struct iio_dev *iio_device_alloc(int sizeof_priv) dev = kzalloc(alloc_size, GFP_KERNEL); if (dev) { + dev->id = id; + dev_set_name(&dev->dev, "iio:device%d", dev->id); dev->dev.groups = dev->groups; dev->dev.type = &iio_device_type; dev->dev.bus = &iio_bus_type; @@ -1514,15 +1524,6 @@ struct iio_dev *iio_device_alloc(int sizeof_priv) mutex_init(&dev->mlock); mutex_init(&dev->info_exist_lock); INIT_LIST_HEAD(&dev->channel_attr_list); - - dev->id = ida_simple_get(&iio_ida, 0, 0, GFP_KERNEL); - if (dev->id < 0) { - /* cannot use a dev_err as the name isn't available */ - pr_err("failed to get device id\n"); - kfree(dev); - return NULL; - } - dev_set_name(&dev->dev, "iio:device%d", dev->id); INIT_LIST_HEAD(&dev->buffer_list); }
This change moves the 'ida_simple_get()' call to be the first one in iio_device_alloc(). It cleans up the error path a bit as we don't need to call any kfree(dev) anymore. We allocate an IIO device only if we have managed to obtain a device ID. Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com> --- drivers/iio/industrialio-core.c | 19 ++++++++++--------- 1 file changed, 10 insertions(+), 9 deletions(-)