Re: [f2fs-dev] [PATCH v1 3/5] treewide: use get_random_u32() when possible

From: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
To: "Jason A. Donenfeld" <Jason@zx2c4.com>
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Subject: Re: [f2fs-dev] [PATCH v1 3/5] treewide: use get_random_u32() when possible
Date: Thu, 6 Oct 2022 16:01:11 +0300	[thread overview]
Message-ID: <Yz7Rl7BXamKQhRzH@smile.fi.intel.com> (raw)
In-Reply-To: <Yz7LCyIAHC6l5mG9@zx2c4.com>

On Thu, Oct 06, 2022 at 06:33:15AM -0600, Jason A. Donenfeld wrote:
> On Thu, Oct 06, 2022 at 10:43:31AM +0200, Jan Kara wrote:

...

> > The code here is effectively doing the
> > 
> > 	parent_group = prandom_u32_max(ngroups);
> > 
> > Similarly here we can use prandom_u32_max(ngroups) like:
> > 
> > 		if (qstr) {
> > 			...
> > 			parent_group = hinfo.hash % ngroups;
> > 		} else
> > 			parent_group = prandom_u32_max(ngroups);
> 
> Nice catch. I'll move these to patch #1.

I believe coccinelle is able to handle this kind of code as well, so Kees'
proposal to use it seems more plausible since it's less error prone and more
flexible / powerful.

-- 
With Best Regards,
Andy Shevchenko