freebsd kernel with SKQ
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andrew 4bde709fd3 Only call cpu_icache_sync_range when inserting an executable page. If the
page is non-executable the contents of the i-cache are unimportant so this
call is just adding unneeded overhead when inserting pages.

While doing research using gem5 with an O3 pipeline and 1k/32k/1M iTLB/L1
iCache/L2 Bjoern Zeeb (bz@) observed a fairly high rate of calls into
arm64_icache_sync_range() from pmap_enter() along with a high number of
instruction fetches and iTLB/iCache hits.

Limiting the calls to arm64_icache_sync_range() to only executable pages,
we observe the iTLB and iCache Hit going down by about 43%. These numbers
are quite misleading when looked at alone as at the same time instructions
retired were reduced by 19.2% and instruction fetches were reduced by 38.8%.
Overall this reduced the runtime of the test program by 22.4%.

On Juno hardware, in steady-state, running the same test, using the cycle
count to determine runtime, we do see a reduction of up to 28.9% in runtime.

While these numbers certainly depend on the program executed, we expect an
overall performance improvement.

Reported by:	bz
Obtained from:	ABT Systems Ltd
MFC after:	1 week
Sponsored by:	The FreeBSD Foundation
2016-09-07 16:22:05 +00:00
bin MFhead @ r305314 2016-09-03 00:50:18 +00:00
cddl MFV r304159: 7277 zdb should be able to print zfs_dbgmsg's 2016-09-03 10:07:46 +00:00
contrib Fix tests/sys/kqueue NetBSD tests on 32-bit platforms by using proper 2016-09-06 17:22:25 +00:00
crypto Add refactored blacklist support to sshd 2016-08-30 14:09:24 +00:00
etc Move tests/sys/kqueue/... to tests/sys/kqueue/libkqueue/... 2016-09-06 08:45:29 +00:00
gnu DIRDEPS_BUILD: Avoid cyclic dependency with libc++. 2016-08-31 19:30:00 +00:00
include Improve compatibility of calls to dirname() on constant strings. 2016-08-26 20:23:10 +00:00
kerberos5 DIRDEPS_BUILD: Update dependencies 2016-06-14 16:55:05 +00:00
lib Renumber the advertising clause. 2016-09-06 15:17:35 +00:00
libexec DIRDEPS_BUILD: Add some missing dirctories to the build. 2016-08-31 19:30:59 +00:00
release Remove the digi(4) manpage and digi from the release notes. 2016-09-01 21:16:29 +00:00
rescue DIRDEPS_BUILD: Build crunchide for the host. 2016-09-01 23:52:25 +00:00
sbin dhclient: add support for interface-mtu (26) 2016-09-02 21:14:29 +00:00
secure DIRDEPS_BUILD: Update dependencies. 2016-08-31 19:30:46 +00:00
share Remove extra period from kern.vt.kbd_reboot 2016-09-07 02:45:09 +00:00
sys Only call cpu_icache_sync_range when inserting an executable page. If the 2016-09-07 16:22:05 +00:00
targets DIRDEPS_BUILD: Build crunchide for the host. 2016-09-01 23:52:25 +00:00
tests Port contrib/netbsd-tests/kernel/kqueue/... as tests/sys/kqueue/... 2016-09-06 08:50:21 +00:00
tools Add cpuset support to separate forked processes. 2016-09-03 00:22:42 +00:00
usr.bin bspatch: add sanity checks on sizes to avoid integer overflow 2016-09-06 19:00:37 +00:00
usr.sbin Teach acpidump how to parse ACPI 5.1 tables found on the development 2016-09-06 10:13:49 +00:00
.arcconfig Remove project.name which is a product of a bygone era. 2016-04-21 04:33:07 +00:00
.arclint phabricator related changes: 2015-04-20 20:33:22 +00:00
COPYRIGHT Bump copyright year. 2015-12-31 11:21:45 +00:00
LOCKS
MAINTAINERS Remove myself from kern_timeout.c yeah! 2016-07-27 20:37:32 +00:00
Makefile Add a 'make print-dir' that simply traverses all directories and prints them. 2016-08-31 19:30:52 +00:00
Makefile.inc1 Bump __FreeBSD_version for crunchgen META_MODE fix in r305254. 2016-09-01 23:22:31 +00:00
Makefile.libcompat Fix in-tree GCC builds after r304681. 2016-08-23 19:29:37 +00:00
ObsoleteFiles.inc Move tests/sys/kqueue/... to tests/sys/kqueue/libkqueue/... 2016-09-06 08:45:29 +00:00
README README: remove nonexistent 'games' directory. 2016-05-18 10:43:13 +00:00
UPDATING Bump __FreeBSD_version for r304787 and add a note about it to UPDATING. 2016-08-25 05:28:02 +00:00

This is the top level of the FreeBSD source directory.  This file
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The Makefile in this directory supports a number of targets for
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The `buildkernel` and `installkernel` targets build and install
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the Makefile in this directory for more information on the
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Building a kernel is a somewhat more involved process.  See build(7), config(8),
and http://www.freebsd.org/doc/en_US.ISO8859-1/books/handbook/kernelconfig.html
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Note: If you want to build and install the kernel with the
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The kernel configuration files reside in the sys/<arch>/conf
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---------------

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cddl		Various commands and libraries under the Common Development
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contrib		Packages contributed by 3rd parties.

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etc		Template files for /etc.

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include		System include files.

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share		Shared resources.

sys		Kernel sources.

tests		Regression tests which can be run by Kyua.  See tests/README
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  http://www.freebsd.org/doc/en_US.ISO8859-1/books/handbook/synching.html