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 uSSyzHGr 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another cpu between these two lines. warn_limit can go negative. Yes, which is why I mentioned it in the description. But compared to before, it should be benign. > Use a single atomic operation instead? Did you have something like this in mind? - if (do_warn && atomic_read(&warn_limit) > 0) { - int remaining = atomic_dec_return(&warn_limit); + if (do_warn) { + int remaining = atomic_dec_if_positive(&warn_limit); Should end up with the same visible result, but w/o going negative. Would you like me to send v2?Vlad