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Date: Tue, 1 Aug 2023 17:59:43 +0200
From: Christoph Hellwig <hch@lst.de>
To: Jeff Moyer <jmoyer@redhat.com>
Cc: Chaitanya Kulkarni <kch@nvidia.com>, dan.j.williams@intel.com,
	vishal.l.verma@intel.com, dave.jiang@intel.com, ira.weiny@intel.com,
	hch@lst.de, nvdimm@lists.linux.dev
Subject: Re: [PATCH V2 1/1] pmem: set QUEUE_FLAG_NOWAIT
Message-ID: <20230801155943.GA13111@lst.de>
References: <20230731224617.8665-1-kch@nvidia.com> <20230731224617.8665-2-kch@nvidia.com> <x491qgmwzuv.fsf@segfault.boston.devel.redhat.com>
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On Tue, Aug 01, 2023 at 11:23:36AM -0400, Jeff Moyer wrote:
> I am slightly embarrassed to have to ask this question, but what are the
> implications of setting this queue flag?  Is the submit_bio routine
> expected to never block?

Yes, at least not significantly.

> Is the I/O expected to be performed
> asynchronously?

Not nessecarily if it is fast enough..