Re: [PATCH v4 10/10] blk-mq: support per-distpatch_queue flush machinery

From: Ming Lei
Date: Wed Sep 24 2014 - 11:21:21 EST


On Wed, Sep 24, 2014 at 6:26 PM, Christoph Hellwig <hch@xxxxxx> wrote:
>> +struct blk_flush_queue *blk_alloc_flush_queue(struct request_queue *q,
>> + struct blk_mq_hw_ctx *hctx, int cmd_size)
>
> I still think this should pass in the numa node instead of the hctx, and
> allow node-local allocation for the old code as well.

We can do that, but have to pass NUMA_NO_NODE for old code
since blk_init_allocated_queue() doesn't provide node information
yet.

> As mentioned earlier
> initializing mq_flush_lock for the !mq case is harmless.

q->mq_ops is another friend for the purpose, :-)

>
> We also should document it where cleary somewhere that for devices that
> have flushes enabled ->init_request can be called for more requests than
> the queue depth, as drivers might allocate some sort of pool for them.

That does make sense.

Thanks,
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/