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Date: Fri, 21 Mar 2025 07:05:50 +0100
From: Christoph Hellwig <hch@lst.de>
To: Daniel Wagner <dwagner@suse.de>
Cc: Hannes Reinecke <hare@suse.de>, Daniel Wagner <wagi@kernel.org>,
	James Smart <james.smart@broadcom.com>,
	Christoph Hellwig <hch@lst.de>, Sagi Grimberg <sagi@grimberg.me>,
	Chaitanya Kulkarni <kch@nvidia.com>,
	Keith Busch <kbusch@kernel.org>, linux-nvme@lists.infradead.org,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH v3 04/18] nvmet-fcloop: refactor fcloop_nport_alloc
Message-ID: <20250321060550.GC3007@lst.de>
References: <20250318-nvmet-fcloop-v3-0-05fec0fc02f6@kernel.org> <20250318-nvmet-fcloop-v3-4-05fec0fc02f6@kernel.org> <a9055e3c-d36f-4706-9fdc-f4532d14adb6@suse.de> <66261f08-5386-4b22-aa6f-7be1d4023fee@flourine.local>
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On Tue, Mar 18, 2025 at 02:38:56PM +0100, Daniel Wagner wrote:
> This means the new entry has always to be allocated first and then we
> either free it again or insert into the list, because it's not possible
> to allocate under the spinlock. Not that beautiful but correctness wins.

Yes, we do that a lot.  And if finding an existing entry is the more
common outcome (I don't think it is here, but I'm not sure), you do
a search first, allocate, and then search again.