On 3/18/21 9:07 AM, Pavel Andrianov wrote:
Hi,
berlin2_adc_probe [1] registers two interrupt handlers:
berlin2_adc_irq [2]
and berlin2_adc_tsen_irq [3]. The interrupt handlers operate with the
same data, for example, modify
priv->data with different masks:
priv->data &= BERLIN2_SM_ADC_MASK;
and
priv->data &= BERLIN2_SM_TSEN_MASK;
If the two interrupt handlers are executed simultaneously, a potential
data race takes place. So, the question is if the situation is
possible. For example, in the case of the handlers are executed on
different CPU cores.
Best regards,
Pavel
[1]
https://elixir.bootlin.com/linux/latest/source/drivers/iio/adc/berlin2-adc.c#L283
[2]
https://elixir.bootlin.com/linux/latest/source/drivers/iio/adc/berlin2-adc.c#L239
[3]
https://elixir.bootlin.com/linux/latest/source/drivers/iio/adc/berlin2-adc.c#L259
Looking at the code there are two functions. berlin2_adc_tsen_read() and
berlin2_adc_read(). These two function are take the same mutex and can
not run concurrently. At the beginning of the protected section the
corresponding interrupt for that function is enabled and at the end
disabled. So at least if the hardware works correctly those two
interrupts will never fire at the same time.
Now, if the hardware misbehaves the two interrupts could still fire at
the same time.
- Lars
