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nvme/pci: Delete misleading queue-wrap comment
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It is not theoretically possible for this driver to wrap twice while
processing completions. The driver allocates only 'queue_depth - 1'
tags, so there can never be more than that to reap when processing a
completion queue. Removing this misleading comment makes it a little
less likely people with broken controllers will blame the driver for
their spurious interrupts.

Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
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Keith Busch authored and Christoph Hellwig committed Dec 21, 2016
1 parent 9fa196e commit ff13b39
Showing 1 changed file with 0 additions and 7 deletions.
7 changes: 0 additions & 7 deletions drivers/nvme/host/pci.c
Original file line number Diff line number Diff line change
Expand Up @@ -712,15 +712,8 @@ static void __nvme_process_cq(struct nvme_queue *nvmeq, unsigned int *tag)
req = blk_mq_tag_to_rq(*nvmeq->tags, cqe.command_id);
nvme_req(req)->result = cqe.result;
blk_mq_complete_request(req, le16_to_cpu(cqe.status) >> 1);

}

/* If the controller ignores the cq head doorbell and continuously
* writes to the queue, it is theoretically possible to wrap around
* the queue twice and mistakenly return IRQ_NONE. Linux only
* requires that 0.1% of your interrupts are handled, so this isn't
* a big problem.
*/
if (head == nvmeq->cq_head && phase == nvmeq->cq_phase)
return;

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