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>>> - unsigned int tail = pipe->tail; >>> - unsigned int mask = pipe->ring_size - 1; >>> + unsigned short head = smp_load_acquire(&pipe->head); >>> + unsigned short tail = pipe->tail; >>> + unsigned short mask = pipe->ring_size - 1; >> >> I dunno... but if we do this, perhaps we should >> s/unsigned int/pipe_index_t instead? >> >> At least this would be more grep friendly. Ack. I'll leave the typedef untouched and convert these to use pipe_index_t. This was an experiment so see if anything breaks with u16 conversion just to get more testing on that scenario. As Rasmus mentioned, leaving the head and tail as u32 on 64bit will lead to better code generation. > > in any case, I think another cleanup before this change makes sense... > pipe->ring_size is overused. pipe_read(), pipe_write() and much more > users do not need "unsigned int mask", they can use pipe_buf(buf, slot) > instead. Ack. I'll add a cleanup patch ahead of this conversion. Thank you both for taking a look. > > Oleg. > -- Thanks and Regards, Prateek