linux_dsm_epyc7002/arch/sparc
Pavel Tatashin 78c943662f sparc64: optimize struct page zeroing
Add an optimized mm_zero_struct_page(), so struct page's are zeroed
without calling memset().  We do eight to ten regular stores based on
the size of struct page.  Compiler optimizes out the conditions of
switch() statement.

SPARC-M6 with 15T of memory, single thread performance:

                               BASE            FIX  OPTIMIZED_FIX
        bootmem_init   28.440467985s   2.305674818s   2.305161615s
free_area_init_nodes  202.845901673s 225.343084508s 172.556506560s
                      --------------------------------------------
Total                 231.286369658s 227.648759326s 174.861668175s

BASE:  current linux
FIX:   This patch series without "optimized struct page zeroing"
OPTIMIZED_FIX: This patch series including the current patch.

bootmem_init() is where memory for struct pages is zeroed during
allocation.  Note, about two seconds in this function is a fixed time:
it does not increase as memory is increased.

Link: http://lkml.kernel.org/r/20171013173214.27300-11-pasha.tatashin@oracle.com
Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com>
Reviewed-by: Steven Sistare <steven.sistare@oracle.com>
Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Reviewed-by: Bob Picco <bob.picco@oracle.com>
Acked-by: David S. Miller <davem@davemloft.net>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-15 18:21:05 -08:00
..
boot License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
configs sparc64: vcc: Enable VCC module in linux 2017-08-15 21:33:50 -07:00
crypto License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
include sparc64: optimize struct page zeroing 2017-11-15 18:21:05 -08:00
kernel Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-11-13 17:56:58 -08:00
lib License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
math-emu License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
mm sparc64: simplify vmemmap_populate 2017-11-15 18:21:05 -08:00
net License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
oprofile sparc: using HZ needs an include of linux/param.h 2009-10-05 00:46:08 -07:00
power License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
prom License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
Kbuild sparc64: Add SHA1 driver making use of the 'sha1' instruction. 2012-08-20 15:08:49 -07:00
Kconfig Revert commit 1a8b6d76dc ("net:add one common config...") 2017-10-09 07:43:06 -07:00
Kconfig.debug License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
Makefile License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00