[PATCH] um: allow using glibc string functions instead of generics

[Richard Weinberger]

----- Ursprüngliche Mail -----
> Von: "anton ivanov" <anton.ivanov at cambridgegreys.com>
> An: "linux-um" <linux-um at lists.infradead.org>
> CC: "richard" <richard at nod.at>, "anton ivanov" <anton.ivanov at cambridgegreys.com>
> Gesendet: Dienstag, 10. November 2020 17:30:34
> Betreff: [PATCH] um: allow using glibc string functions instead of generics

> From: Anton Ivanov <anton.ivanov at cambridgegreys.com>
> 
> UML kernel runs as a normal userspace process and can use the
> optimized glibc strings functions like strcpy, memcpy, etc.
> 
> The support is optional and is turned on/of using a config
> option.
> 
> Using glibc functions results in a slightly smaller executable
> when linked dynamically as well as anything between 1% and 5%
> performance improvements.

On what workload did you see such a huge performance improvement?
The in-kernel variants of memcpy and such are already well optimized.
So I'm a little surprised.

Thanks,
//richard