linux_dsm_epyc7002/arch
Anton Blanchard 5a0e9b5718 powerpc: Use lwsync for acquire barrier if CPU supports it
Nick Piggin discovered that lwsync barriers around locks were faster than isync
on 970. That was a long time ago and I completely dropped the ball in testing
his patches across other ppc64 processors.

Turns out the idea helps on other chips. Using a microbenchmark that
uses a lot of threads to contend on a global pthread mutex (and therefore a
global futex), POWER6 improves 8% and POWER7 improves 2%. I checked POWER5
and while I couldn't measure an improvement, there was no regression.

This patch uses the lwsync patching code to replace the isyncs with lwsyncs
on CPUs that support the instruction. We were marking POWER3 and RS64 as lwsync
capable but in reality they treat it as a full sync (ie slow). Remove the
CPU_FTR_LWSYNC bit from these CPUs so they continue to use the faster isync
method.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-02-17 14:03:16 +11:00
..
alpha alpha: cpumask_of_node() should handle -1 as a node 2010-01-14 13:21:35 -05:00
arm OMAP: hsmmc: fix memory leak 2010-02-10 09:20:33 -08:00
avr32 avr32: clean up memory allocation in at32_add_device_mci 2009-12-28 12:33:00 +01:00
blackfin blackfin,kgdb: Do not put PC in gdb_regs into retx. 2010-01-07 11:58:37 -06:00
cris Merge branch 'for-33' of git://repo.or.cz/linux-kbuild 2009-12-17 07:23:42 -08:00
frv FDPIC: Respect PT_GNU_STACK exec protection markings when creating NOMMU stack 2010-01-06 18:16:02 -08:00
h8300 Merge branch 'for-33' of git://repo.or.cz/linux-kbuild 2009-12-17 07:23:42 -08:00
ia64 [IA64] preserve personality flag bits across exec 2010-02-12 08:17:58 -08:00
m32r elf: kill USE_ELF_CORE_DUMP 2009-12-16 07:20:12 -08:00
m68k m68knommu: fix definitions of __pa() and __va() 2010-01-12 20:51:45 -08:00
m68knommu m68knommu: fix invalid flags on coldfire pit clocksource 2010-01-16 12:15:38 -08:00
microblaze microblaze: Invalidate dcache before enabling it 2010-02-08 11:39:18 +01:00
mips MIPS: Don't probe reserved EntryHi bits. 2010-02-10 22:15:46 +01:00
mn10300 mn10300: update the ASB2303 defconfig 2010-01-11 09:34:10 -08:00
parisc parisc: fix tracing of signals 2010-02-12 08:51:58 -08:00
powerpc powerpc: Use lwsync for acquire barrier if CPU supports it 2010-02-17 14:03:16 +11:00
s390 [S390] Fix struct _lowcore layout. 2010-02-09 09:46:23 +01:00
score mm: make totalhigh_pages unsigned long 2010-01-11 09:34:03 -08:00
sh sh64: fix tracing of signals. 2010-02-15 14:17:45 +09:00
sparc Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-2.6 2010-02-11 14:00:27 -08:00
um Unrot uml mconsole a bit 2010-01-14 09:05:26 -05:00
x86 x86: ELF_PLAT_INIT() shouldn't worry about TIF_IA32 2010-02-16 08:51:49 -08:00
xtensa Merge branch 'for-33' of git://repo.or.cz/linux-kbuild 2009-12-17 07:23:42 -08:00
.gitignore
Kconfig hw-breakpoints: Fix hardware breakpoints -> perf events dependency 2009-12-18 13:11:51 +01:00