On Mon, 5 Aug 2019 11:57:11 -0700
Denis Ciocca <denis.ciocca@xxxxxx> wrote:
> This patch is removing the buffer allocation at each buffer enable.
> We just allocate enough memory in the main structure during probe
> to cover maximum size needed (that anyway is pretty small) [16bytes].
>
> Signed-off-by: Denis Ciocca <denis.ciocca@xxxxxx>
Applied to the togreg branch of iio.git and pushed out as testing for
the autobuilders to play with it.
This came out very nicely. Thanks,
Jonathan
> ---
> drivers/iio/accel/st_accel_buffer.c | 12 +-----------
> drivers/iio/gyro/st_gyro_buffer.c | 12 +-----------
> drivers/iio/magnetometer/st_magn_buffer.c | 12 +-----------
> drivers/iio/pressure/st_pressure_buffer.c | 12 +-----------
> include/linux/iio/common/st_sensors.h | 14 +++++++++-----
> 5 files changed, 13 insertions(+), 49 deletions(-)
>
> diff --git a/drivers/iio/accel/st_accel_buffer.c b/drivers/iio/accel/st_accel_buffer.c
> index 59dcef02ec19..9f2b40474b8e 100644
> --- a/drivers/iio/accel/st_accel_buffer.c
> +++ b/drivers/iio/accel/st_accel_buffer.c
> @@ -31,17 +31,11 @@ int st_accel_trig_set_state(struct iio_trigger *trig, bool state)
>
> static int st_accel_buffer_postenable(struct iio_dev *indio_dev)
> {
> - struct st_sensor_data *adata = iio_priv(indio_dev);
> int err;
>
> - adata->buffer_data = kmalloc(indio_dev->scan_bytes,
> - GFP_DMA | GFP_KERNEL);
> - if (!adata->buffer_data)
> - return -ENOMEM;
> -
> err = iio_triggered_buffer_postenable(indio_dev);
> if (err < 0)
> - goto st_accel_free_buffer;
> + return err;
>
> err = st_sensors_set_axis_enable(indio_dev,
> (u8)indio_dev->active_scan_mask[0]);
> @@ -58,14 +52,11 @@ static int st_accel_buffer_postenable(struct iio_dev *indio_dev)
> st_sensors_set_axis_enable(indio_dev, ST_SENSORS_ENABLE_ALL_AXIS);
> st_accel_buffer_predisable:
> iio_triggered_buffer_predisable(indio_dev);
> -st_accel_free_buffer:
> - kfree(adata->buffer_data);
> return err;
> }
>
> static int st_accel_buffer_predisable(struct iio_dev *indio_dev)
> {
> - struct st_sensor_data *adata = iio_priv(indio_dev);
> int err, err2;
>
> err = st_sensors_set_enable(indio_dev, false);
> @@ -79,7 +70,6 @@ static int st_accel_buffer_predisable(struct iio_dev *indio_dev)
> if (!err)
> err = err2;
>
> - kfree(adata->buffer_data);
> return err;
> }
>
> diff --git a/drivers/iio/gyro/st_gyro_buffer.c b/drivers/iio/gyro/st_gyro_buffer.c
> index c6ddfecc1fc3..7465ad62391c 100644
> --- a/drivers/iio/gyro/st_gyro_buffer.c
> +++ b/drivers/iio/gyro/st_gyro_buffer.c
> @@ -31,17 +31,11 @@ int st_gyro_trig_set_state(struct iio_trigger *trig, bool state)
>
> static int st_gyro_buffer_postenable(struct iio_dev *indio_dev)
> {
> - struct st_sensor_data *gdata = iio_priv(indio_dev);
> int err;
>
> - gdata->buffer_data = kmalloc(indio_dev->scan_bytes,
> - GFP_DMA | GFP_KERNEL);
> - if (!gdata->buffer_data)
> - return -ENOMEM;
> -
> err = iio_triggered_buffer_postenable(indio_dev);
> if (err < 0)
> - goto st_gyro_free_buffer;
> + return err;
>
> err = st_sensors_set_axis_enable(indio_dev,
> (u8)indio_dev->active_scan_mask[0]);
> @@ -58,15 +52,12 @@ static int st_gyro_buffer_postenable(struct iio_dev *indio_dev)
> st_sensors_set_axis_enable(indio_dev, ST_SENSORS_ENABLE_ALL_AXIS);
> st_gyro_buffer_predisable:
> iio_triggered_buffer_predisable(indio_dev);
> -st_gyro_free_buffer:
> - kfree(gdata->buffer_data);
> return err;
> }
>
> static int st_gyro_buffer_predisable(struct iio_dev *indio_dev)
> {
> int err, err2;
> - struct st_sensor_data *gdata = iio_priv(indio_dev);
>
> err = st_sensors_set_enable(indio_dev, false);
> if (err < 0)
> @@ -79,7 +70,6 @@ static int st_gyro_buffer_predisable(struct iio_dev *indio_dev)
> if (!err)
> err = err2;
>
> - kfree(gdata->buffer_data);
> return err;
> }
>
> diff --git a/drivers/iio/magnetometer/st_magn_buffer.c b/drivers/iio/magnetometer/st_magn_buffer.c
> index 658d627dad8e..bb425c167a96 100644
> --- a/drivers/iio/magnetometer/st_magn_buffer.c
> +++ b/drivers/iio/magnetometer/st_magn_buffer.c
> @@ -31,17 +31,11 @@ int st_magn_trig_set_state(struct iio_trigger *trig, bool state)
>
> static int st_magn_buffer_postenable(struct iio_dev *indio_dev)
> {
> - struct st_sensor_data *mdata = iio_priv(indio_dev);
> int err;
>
> - mdata->buffer_data = kmalloc(indio_dev->scan_bytes,
> - GFP_DMA | GFP_KERNEL);
> - if (!mdata->buffer_data)
> - return -ENOMEM;
> -
> err = iio_triggered_buffer_postenable(indio_dev);
> if (err < 0)
> - goto st_magn_free_buffer;
> + return err;
>
> err = st_sensors_set_enable(indio_dev, true);
> if (err < 0)
> @@ -51,14 +45,11 @@ static int st_magn_buffer_postenable(struct iio_dev *indio_dev)
>
> st_magn_buffer_predisable:
> iio_triggered_buffer_predisable(indio_dev);
> -st_magn_free_buffer:
> - kfree(mdata->buffer_data);
> return err;
> }
>
> static int st_magn_buffer_predisable(struct iio_dev *indio_dev)
> {
> - struct st_sensor_data *mdata = iio_priv(indio_dev);
> int err, err2;
>
> err = st_sensors_set_enable(indio_dev, false);
> @@ -67,7 +58,6 @@ static int st_magn_buffer_predisable(struct iio_dev *indio_dev)
> if (!err)
> err = err2;
>
> - kfree(mdata->buffer_data);
> return err;
> }
>
> diff --git a/drivers/iio/pressure/st_pressure_buffer.c b/drivers/iio/pressure/st_pressure_buffer.c
> index 77cb2d862f19..418dbf9e6e1e 100644
> --- a/drivers/iio/pressure/st_pressure_buffer.c
> +++ b/drivers/iio/pressure/st_pressure_buffer.c
> @@ -31,17 +31,11 @@ int st_press_trig_set_state(struct iio_trigger *trig, bool state)
>
> static int st_press_buffer_postenable(struct iio_dev *indio_dev)
> {
> - struct st_sensor_data *press_data = iio_priv(indio_dev);
> int err;
>
> - press_data->buffer_data = kmalloc(indio_dev->scan_bytes,
> - GFP_DMA | GFP_KERNEL);
> - if (!press_data->buffer_data)
> - return -ENOMEM;
> -
> err = iio_triggered_buffer_postenable(indio_dev);
> if (err < 0)
> - goto st_press_free_buffer;
> + return err;
>
> err = st_sensors_set_enable(indio_dev, true);
> if (err < 0)
> @@ -51,14 +45,11 @@ static int st_press_buffer_postenable(struct iio_dev *indio_dev)
>
> st_press_buffer_predisable:
> iio_triggered_buffer_predisable(indio_dev);
> -st_press_free_buffer:
> - kfree(press_data->buffer_data);
> return err;
> }
>
> static int st_press_buffer_predisable(struct iio_dev *indio_dev)
> {
> - struct st_sensor_data *press_data = iio_priv(indio_dev);
> int err, err2;
>
> err = st_sensors_set_enable(indio_dev, false);
> @@ -67,7 +58,6 @@ static int st_press_buffer_predisable(struct iio_dev *indio_dev)
> if (!err)
> err = err2;
>
> - kfree(press_data->buffer_data);
> return err;
> }
>
> diff --git a/include/linux/iio/common/st_sensors.h b/include/linux/iio/common/st_sensors.h
> index 4d0889bf1c6c..686be532f4cb 100644
> --- a/include/linux/iio/common/st_sensors.h
> +++ b/include/linux/iio/common/st_sensors.h
> @@ -20,8 +20,12 @@
>
> #include <linux/platform_data/st_sensors_pdata.h>
>
> -#define ST_SENSORS_TX_MAX_LENGTH 2
> -#define ST_SENSORS_RX_MAX_LENGTH 6
> +/*
> + * Buffer size max case: 2bytes per channel, 3 channels in total +
> + * 8bytes timestamp channel (s64)
> + */
> +#define ST_SENSORS_MAX_BUFFER_SIZE (ALIGN(2 * 3, sizeof(s64)) + \
> + sizeof(s64))
>
> #define ST_SENSORS_ODR_LIST_MAX 10
> #define ST_SENSORS_FULLSCALE_AVL_MAX 10
> @@ -215,7 +219,6 @@ struct st_sensor_settings {
> * @vdd_io: Pointer to sensor's Vdd-IO power supply
> * @regmap: Pointer to specific sensor regmap configuration.
> * @enabled: Status of the sensor (false->off, true->on).
> - * @buffer_data: Data used by buffer part.
> * @odr: Output data rate of the sensor [Hz].
> * num_data_channels: Number of data channels used in buffer.
> * @drdy_int_pin: Redirect DRDY on pin 1 (1) or pin 2 (2).
> @@ -224,6 +227,7 @@ struct st_sensor_settings {
> * @edge_irq: the IRQ triggers on edges and need special handling.
> * @hw_irq_trigger: if we're using the hardware interrupt on the sensor.
> * @hw_timestamp: Latest timestamp from the interrupt handler, when in use.
> + * @buffer_data: Data used by buffer part.
> */
> struct st_sensor_data {
> struct device *dev;
> @@ -237,8 +241,6 @@ struct st_sensor_data {
>
> bool enabled;
>
> - char *buffer_data;
> -
> unsigned int odr;
> unsigned int num_data_channels;
>
> @@ -249,6 +251,8 @@ struct st_sensor_data {
> bool edge_irq;
> bool hw_irq_trigger;
> s64 hw_timestamp;
> +
> + char buffer_data[ST_SENSORS_MAX_BUFFER_SIZE] ____cacheline_aligned;
> };
>
> #ifdef CONFIG_IIO_BUFFER
