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Date: Mon, 6 Jan 2025 09:55:54 +0100
From: Christoph Hellwig <hch@lst.de>
To: John Garry <john.g.garry@oracle.com>
Cc: Christoph Hellwig <hch@lst.de>, Jens Axboe <axboe@kernel.dk>,
	Damien Le Moal <dlemoal@kernel.org>,
	Niklas Cassel <cassel@kernel.org>,
	"Martin K. Petersen" <martin.petersen@oracle.com>,
	linux-block@vger.kernel.org, linux-ide@vger.kernel.org,
	linux-scsi@vger.kernel.org
Subject: Re: [PATCH 4/4] block: simplify tag allocation policy selection
Message-ID: <20250106085554.GA19343@lst.de>
References: <20250106083531.799976-1-hch@lst.de> <20250106083531.799976-5-hch@lst.de> <10f1383a-fe7e-4cf8-a15f-14cd4385a7de@oracle.com>
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On Mon, Jan 06, 2025 at 08:50:20AM +0000, John Garry wrote:
>>   	.can_queue		= SIL24_MAX_CMDS,
>>   	.sg_tablesize		= SIL24_MAX_SGE,
>>   	.dma_boundary		= ATA_DMA_BOUNDARY,
>> -	.tag_alloc_policy	= BLK_TAG_ALLOC_FIFO,
>
> nit: maybe that could be a separate patch, but no biggie

I though about that, but if felt a bit overkill.

>> +	/*
>> +	 * Allocate tags starting from last allocated tag.
>> +	 */
>> +	bool tag_alloc_policy_rr : 1;
>
> Is it proper to use bool here? I am not sure. Others use unsigned int or 
> unsigned.

Yes, you can use any unsigned type for a single-bit bitfield.  Most of
the existing uses just predate the availability of bool or were copy
and pasted after that.

>
> nit: coding style elsewhere in scsi_host_template would be to use 
> "tag_alloc_policy_rr:1;"

Yes, but that's against the normal kernel coding style, so we'd better
stop adding more of that.