atomic use is not atomic?

[Andy Shevchenko <andy.shevchenko@xxxxxxxxx>]

Hi!

Can anybody explain this code [1] in terms of atomicity?

  if (!atomic_read(&trig->use_count)) {
    atomic_set(&trig->use_count, CONFIG_IIO_CONSUMERS_PER_TRIGGER);
    ...
  }

AFAIU how atomics are supposed to work the above doesn't do anything
atomically. I.o.w. use_count may be simple int with the same effect.

What did I miss?

[1]: https://elixir.bootlin.com/linux/latest/source/drivers/iio/industrialio-trigger.c#L166

-- 
With Best Regards,
Andy Shevchenko