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Date:   Tue, 31 Oct 2023 02:04:13 +0200
From:   Laurent Pinchart <laurent.pinchart@ideasonboard.com>
To:     Ghanshyam Agrawal <ghanshyam1898@gmail.com>
Cc:     linux-media@vger.kernel.org
Subject: Re: Need some guidance working on a TODO item
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Hello Ghanshyam,

CC'ing the linux-media mailing list, to let other developers chime in as
well.

On Sat, Oct 28, 2023 at 04:07:03PM +0530, Ghanshyam Agrawal wrote:
> Hello Laurent,
> 
> Line 90 in file "drivers/media/usb/uvc/uvcvideo.h" in linux_mainline tree
> states
> 
> /*
>  * TODO: Put the most frequently accessed fields at the beginning of
>  * structures to maximize cache efficiency.
>  */
> 
> I am working on this todo item. Can you please guide me regarding 
> 
> 1. How can I find the number of accesses of each of the fields?

By reading through the code :-) It may be possible to instrument that,
but I have no idea how.

> 2. How can I find out the cache efficiency?

Do you know how caches work ?

> 3. When we say cache, which cache are we talking about?

The CPU caches, any level.

-- 
Regards,

Laurent Pinchart