The glibc.tune namespace is vaguely named since it is a 'tunable', so
give it a more specific name that describes what it refers to. Rename
the tunable namespace to 'cpu' to more accurately reflect what it
encompasses. Also rename glibc.tune.cpu to glibc.cpu.name since
glibc.cpu.cpu is weird.
* NEWS: Mention the change.
* elf/dl-tunables.list: Rename tune namespace to cpu.
* sysdeps/powerpc/dl-tunables.list: Likewise.
* sysdeps/x86/dl-tunables.list: Likewise.
* sysdeps/aarch64/dl-tunables.list: Rename tune.cpu to
cpu.name.
* elf/dl-hwcaps.c (_dl_important_hwcaps): Adjust.
* elf/dl-hwcaps.h (GET_HWCAP_MASK): Likewise.
* manual/README.tunables: Likewise.
* manual/tunables.texi: Likewise.
* sysdeps/powerpc/cpu-features.c: Likewise.
* sysdeps/unix/sysv/linux/aarch64/cpu-features.c
(init_cpu_features): Likewise.
* sysdeps/x86/cpu-features.c: Likewise.
* sysdeps/x86/cpu-features.h: Likewise.
* sysdeps/x86/cpu-tunables.c: Likewise.
* sysdeps/x86_64/Makefile: Likewise.
* sysdeps/x86/dl-cet.c: Likewise.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
On POWER8, unaligned memory accesses to cached memory has little impact
on performance as opposed to its ancestors.
It is disabled by default and will only be available when the tunable
glibc.tune.cached_memopt is set to 1.
__memcpy_power8_cached __memcpy_power7
============================================================
max-size=4096: 33325.70 ( 12.65%) 38153.00
max-size=8192: 32878.20 ( 11.17%) 37012.30
max-size=16384: 33782.20 ( 11.61%) 38219.20
max-size=32768: 33296.20 ( 11.30%) 37538.30
max-size=65536: 33765.60 ( 10.53%) 37738.40
* manual/tunables.texi (Hardware Capability Tunables): Document
glibc.tune.cached_memopt.
* sysdeps/powerpc/cpu-features.c: New file.
* sysdeps/powerpc/cpu-features.h: New file.
* sysdeps/powerpc/dl-procinfo.c [!IS_IN(ldconfig)]: Add
_dl_powerpc_cpu_features.
* sysdeps/powerpc/dl-tunables.list: New file.
* sysdeps/powerpc/ldsodefs.h: Include cpu-features.h.
* sysdeps/powerpc/powerpc32/power4/multiarch/init-arch.h
(INIT_ARCH): Initialize use_aligned_memopt.
* sysdeps/powerpc/powerpc64/dl-machine.h [defined(SHARED &&
IS_IN(rtld))]: Restrict dl_platform_init availability and
initialize CPU features used by tunables.
* sysdeps/powerpc/powerpc64/multiarch/Makefile (sysdep_routines):
Add memcpy-power8-cached.
* sysdeps/powerpc/powerpc64/multiarch/ifunc-impl-list.c: Add
__memcpy_power8_cached.
* sysdeps/powerpc/powerpc64/multiarch/memcpy.c: Likewise.
* sysdeps/powerpc/powerpc64/multiarch/memcpy-power8-cached.S:
New file.
Reviewed-by: Rajalakshmi Srinivasaraghavan <raji@linux.vnet.ibm.com>
