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Date: Fri, 7 Nov 2025 16:11:30 -0800
From: Andrew Morton <akpm@linux-foundation.org>
To: David Laight <david.laight.linux@gmail.com>
Cc: Junrui Luo <moonafterrain@outlook.com>, linux-kernel@vger.kernel.org,
 pmladek@suse.com, rostedt@goodmis.org, andriy.shevchenko@linux.intel.com,
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Subject: Re: [PATCH 1/4] lib/sprintf: add scnprintf_append() helper function
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On Fri, 7 Nov 2025 09:12:46 +0000 David Laight <david.laight.linux@gmail.com> wrote:

> > I wonder if we should instead implement a kasprintf() version of this
> > which reallocs each time and then switch all the callers over to that.
> 
> That adds the cost of a malloc, and I, like kasprintf() probably ends up
> doing all the work of snprintf twice.

There is no need at all to optimize the performance of scruffy once-off
string pasting functions.  For these it's better to optimize for
readability, reliability.  maintainability.