From: Bart Van Assche <bvanassche@acm.org>
To: Deepak R Varma <drv@mailo.com>, Michael Reed <mdr@sgi.com>,
"James E.J. Bottomley" <jejb@linux.ibm.com>,
"Martin K. Petersen" <martin.petersen@oracle.com>,
linux-scsi@vger.kernel.org, linux-kernel@vger.kernel.org
Cc: Saurabh Singh Sengar <ssengar@microsoft.com>,
Praveen Kumar <kumarpraveen@linux.microsoft.com>
Subject: Re: [PATCH] scsi: qla1280: Replace arithmetic addition by bitwise OR
Date: Sat, 11 Feb 2023 15:25:03 -0800 [thread overview]
Message-ID: <aed35866-507c-870c-7e8a-c1868bcaa084@acm.org> (raw)
In-Reply-To: <Y+I7/QpQYjBXutLf@ubun2204.myguest.virtualbox.org>
On 2/7/23 03:54, Deepak R Varma wrote:
> When adding two bit-field mask values, an OR operation offers higher
> performance over an arithmetic operation. So, convert such addition to
> an OR based expression.
Where is the evidence that supports this claim? On the following page I
read that there is no performance difference when using a modern CPU:
https://cs.stackexchange.com/questions/75811/why-is-addition-as-fast-as-bit-wise-operations-in-modern-processors
> Issue identified using orplus.cocci semantic patch script.
Where is that script located? Can it be deleted such that submission of
patches similar to this patch stops?
Thanks,
Bart.
next prev parent reply other threads:[~2023-02-11 23:25 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-02-07 11:54 [PATCH] scsi: qla1280: Replace arithmetic addition by bitwise OR Deepak R Varma
2023-02-11 23:25 ` Bart Van Assche [this message]
2023-02-12 15:08 ` Deepak R Varma
2023-02-12 15:11 ` Julia Lawall
2023-02-12 15:25 ` Deepak R Varma
2023-02-12 16:15 ` Julia Lawall
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