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> > Please use guard(spinlock_irqsave) in new code instead of spin_lock_irqsave() + goto out_unlock > + spin_unlock_irqrestore(). > That will make this function significantly easier to read and to > maintain. Got it. > >> + >> +    if (!map->cleared) { >> +        if (depth > 0) { >> +            word_mask = (~0UL) >> (BITS_PER_LONG - depth); >> +            /* >> +             * The current behavior is to always retry after moving >> +             * ->cleared to word, and we change it to retry in case >> +             * of any free bits. To avoid dead loop, we need to take > > What is a "dead loop"? Did you perhaps want to write "infinite loop"? Yeah. I suppose so. > >> +             * wrap & alloc_hint into account. Without this, a soft >> +             * lockup was detected in our test environment. > > Source code comments should not refer to "our test environment". Code > that is intended for upstream inclusion should work for all setups. Got it. > >> +             */ >> +            if (!wrap && alloc_hint) >> +                word_mask &= ~((1UL << alloc_hint) - 1); > > Above I see an open-coded __clear_bit() operation. Has it been > considered to use __clear_bit() instead of open-coding it? It is meant to reset multiple bits to zero, but __clear_bit() is only capable of resetting one bit to zero. Thanks. > > Thanks, > > Bart.