[PATCH v2] tunables, aarch64: New tunable to override cpu

[Carlos O'Donell]

On 06/29/2017 05:52 AM, Siddhesh Poyarekar wrote:
> Add a new tunable (glibc.tune.cpu) to override CPU identification on
> aarch64.  This is useful in two cases: one where it is desirable to
> pretend to be another CPU for purposes of testing or because routines
> written for that CPU are beneficial for specific workloads and second
> where the underlying kernel does not support emulation of MRS to get
> the MIDR of the CPU.
> 
> 	* elf/dl-tunables.h (tunable_is_name): Move from...
> 	* elf/dl-tunables.c (is_name): ... here.
> 	(parse_tunables, __tunables_init): Adjust.
> 	* manual/tunables.texi: Document glibc.tune.cpu.
> 	* sysdeps/aarch64/dl-tunables.list: New file.
> 	* sysdeps/unix/sysv/linux/aarch64/cpu-features.c (struct
> 	cpu_list): New type.
> 	(cpu_list): New list of CPU names and their MIDR.
> 	(get_midr_from_mcpu): New function.
> 	(init_cpu_features): Override MIDR if necessary.
Looks good to me.

I assume it defaults to SXID_ERASE.

-- 
Cheers,
Carlos.