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Date: Thu, 27 Jun 2024 17:47:59 +0200
From: Christoph Hellwig <hch@lst.de>
To: Kanchan Joshi <joshi.k@samsung.com>
Cc: Christoph Hellwig <hch@lst.de>, Jens Axboe <axboe@kernel.dk>,
	"Martin K . Petersen" <martin.petersen@oracle.com>,
	linux-block@vger.kernel.org
Subject: Re: [PATCH 5/5] block: remove bio_integrity_process
Message-ID: <20240627154759.GA25261@lst.de>
References: <20240626045950.189758-1-hch@lst.de> <CGME20240626050052epcas5p29fc1cf1ef40fdec63860f6d6df9ffad1@epcas5p2.samsung.com> <20240626045950.189758-6-hch@lst.de> <a7fd0e31-63bd-8fff-d7d4-6ba990098e7a@samsung.com>
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On Thu, Jun 27, 2024 at 09:06:56PM +0530, Kanchan Joshi wrote:
> The bi->csum_type is constant as far as this bio_for_each_segment loop 
> is concerned.
> Seems wasteful processing, and can rather be moved out where we set a 
> function pointer to point to either ext_pi_crc64_generate or 
> t10_pi_generate once.

A function pointer is way more expensive than a few branches, especially
easily predictable ones.