<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux.git/arch/x86/kernel/cpu/intel.c, branch v3.15</title>
<subtitle>Linux kernel source tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/'/>
<entry>
<title>Merge branch 'x86-nuke-platforms-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip</title>
<updated>2014-04-02T20:15:58+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2014-04-02T20:15:58+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=467cbd207abdbfe29514b5804a22661ab6e80dc6'/>
<id>467cbd207abdbfe29514b5804a22661ab6e80dc6</id>
<content type='text'>
Pull x86 old platform removal from Peter Anvin:
 "This patchset removes support for several completely obsolete
  platforms, where the maintainers either have completely vanished or
  acked the removal.  For some of them it is questionable if there even
  exists functional specimens of the hardware"

Geert Uytterhoeven apparently thought this was a April Fool's pull request ;)

* 'x86-nuke-platforms-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86, platforms: Remove NUMAQ
  x86, platforms: Remove SGI Visual Workstation
  x86, apic: Remove support for IBM Summit/EXA chipset
  x86, apic: Remove support for ia32-based Unisys ES7000
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull x86 old platform removal from Peter Anvin:
 "This patchset removes support for several completely obsolete
  platforms, where the maintainers either have completely vanished or
  acked the removal.  For some of them it is questionable if there even
  exists functional specimens of the hardware"

Geert Uytterhoeven apparently thought this was a April Fool's pull request ;)

* 'x86-nuke-platforms-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86, platforms: Remove NUMAQ
  x86, platforms: Remove SGI Visual Workstation
  x86, apic: Remove support for IBM Summit/EXA chipset
  x86, apic: Remove support for ia32-based Unisys ES7000
</pre>
</div>
</content>
</entry>
<entry>
<title>x86, cpu: Add forcepae parameter for booting PAE kernels on PAE-disabled Pentium M</title>
<updated>2014-03-20T23:31:54+00:00</updated>
<author>
<name>Chris Bainbridge</name>
<email>chris.bainbridge@gmail.com</email>
</author>
<published>2014-03-07T11:40:42+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=69f2366c9456d0ce784cf5aba87ee77eeadc1d5e'/>
<id>69f2366c9456d0ce784cf5aba87ee77eeadc1d5e</id>
<content type='text'>
Many Pentium M systems disable PAE but may have a functionally usable PAE
implementation. This adds the "forcepae" parameter which bypasses the boot
check for PAE, and sets the CPU as being PAE capable. Using this parameter
will taint the kernel with TAINT_CPU_OUT_OF_SPEC.

Signed-off-by: Chris Bainbridge &lt;chris.bainbridge@gmail.com&gt;
Link: http://lkml.kernel.org/r/20140307114040.GA4997@localhost
Acked-by: Borislav Petkov &lt;bp@suse.de&gt;
Signed-off-by: H. Peter Anvin &lt;hpa@zytor.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Many Pentium M systems disable PAE but may have a functionally usable PAE
implementation. This adds the "forcepae" parameter which bypasses the boot
check for PAE, and sets the CPU as being PAE capable. Using this parameter
will taint the kernel with TAINT_CPU_OUT_OF_SPEC.

Signed-off-by: Chris Bainbridge &lt;chris.bainbridge@gmail.com&gt;
Link: http://lkml.kernel.org/r/20140307114040.GA4997@localhost
Acked-by: Borislav Petkov &lt;bp@suse.de&gt;
Signed-off-by: H. Peter Anvin &lt;hpa@zytor.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>x86, intel: Make MSR_IA32_MISC_ENABLE bit constants systematic</title>
<updated>2014-03-13T22:55:46+00:00</updated>
<author>
<name>H. Peter Anvin</name>
<email>hpa@linux.intel.com</email>
</author>
<published>2014-03-13T22:40:52+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=0b131be8d4125b32eb5b94e84f4f9dee6a0ef797'/>
<id>0b131be8d4125b32eb5b94e84f4f9dee6a0ef797</id>
<content type='text'>
Replace somewhat arbitrary constants for bits in MSR_IA32_MISC_ENABLE
with verbose but systematic ones.  Add _BIT defines for all the rest
of them, too.

Signed-off-by: H. Peter Anvin &lt;hpa@linux.intel.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Replace somewhat arbitrary constants for bits in MSR_IA32_MISC_ENABLE
with verbose but systematic ones.  Add _BIT defines for all the rest
of them, too.

Signed-off-by: H. Peter Anvin &lt;hpa@linux.intel.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>x86, Intel: Convert to the new bit access MSR accessors</title>
<updated>2014-03-13T22:35:09+00:00</updated>
<author>
<name>Borislav Petkov</name>
<email>bp@suse.de</email>
</author>
<published>2014-03-09T17:05:25+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=c0a639ad0bc6b178b46996bd1f821a04643e2bde'/>
<id>c0a639ad0bc6b178b46996bd1f821a04643e2bde</id>
<content type='text'>
... and save some lines of code.

Signed-off-by: Borislav Petkov &lt;bp@suse.de&gt;
Link: http://lkml.kernel.org/r/1394384725-10796-4-git-send-email-bp@alien8.de
Signed-off-by: H. Peter Anvin &lt;hpa@linux.intel.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
... and save some lines of code.

Signed-off-by: Borislav Petkov &lt;bp@suse.de&gt;
Link: http://lkml.kernel.org/r/1394384725-10796-4-git-send-email-bp@alien8.de
Signed-off-by: H. Peter Anvin &lt;hpa@linux.intel.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>x86, platforms: Remove NUMAQ</title>
<updated>2014-02-27T16:07:39+00:00</updated>
<author>
<name>H. Peter Anvin</name>
<email>hpa@linux.intel.com</email>
</author>
<published>2014-02-25T20:14:06+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=b5660ba76b41af69a0c09d434927bb4b4cadd4b1'/>
<id>b5660ba76b41af69a0c09d434927bb4b4cadd4b1</id>
<content type='text'>
The NUMAQ support seems to be unmaintained, remove it.

Cc: Paul Gortmaker &lt;paul.gortmaker@windriver.com&gt;
Cc: David Rientjes &lt;rientjes@google.com&gt;
Acked-by: Paul E. McKenney &lt;paulmck@linux.vnet.ibm.com&gt;
Signed-off-by: H. Peter Anvin &lt;hpa@linux.intel.com&gt;
Link: http://lkml.kernel.org/r/n/530CFD6C.7040705@zytor.com
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The NUMAQ support seems to be unmaintained, remove it.

Cc: Paul Gortmaker &lt;paul.gortmaker@windriver.com&gt;
Cc: David Rientjes &lt;rientjes@google.com&gt;
Acked-by: Paul E. McKenney &lt;paulmck@linux.vnet.ibm.com&gt;
Signed-off-by: H. Peter Anvin &lt;hpa@linux.intel.com&gt;
Link: http://lkml.kernel.org/r/n/530CFD6C.7040705@zytor.com
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge branch 'linus' into x86/urgent</title>
<updated>2014-01-25T08:16:14+00:00</updated>
<author>
<name>Ingo Molnar</name>
<email>mingo@kernel.org</email>
</author>
<published>2014-01-25T08:16:14+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=2b45e0f9f34f718725e093f4e335600811d7105a'/>
<id>2b45e0f9f34f718725e093f4e335600811d7105a</id>
<content type='text'>
Merge in the x86 changes to apply a fix.

Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Merge in the x86 changes to apply a fix.

Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>mm, x86: Revisit tlb_flushall_shift tuning for page flushes except on IvyBridge</title>
<updated>2014-01-25T08:10:44+00:00</updated>
<author>
<name>Mel Gorman</name>
<email>mgorman@suse.de</email>
</author>
<published>2014-01-21T22:33:22+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=b9a3b4c976c1209957326537ad5c0bb633dfd764'/>
<id>b9a3b4c976c1209957326537ad5c0bb633dfd764</id>
<content type='text'>
There was a large ebizzy performance regression that was
bisected to commit 611ae8e3 (x86/tlb: enable tlb flush range
support for x86).  The problem was related to the
tlb_flushall_shift tuning for IvyBridge which was altered.  The
problem is that it is not clear if the tuning values for each
CPU family is correct as the methodology used to tune the values
is unclear.

This patch uses a conservative tlb_flushall_shift value for all
CPU families except IvyBridge so the decision can be revisited
if any regression is found as a result of this change.
IvyBridge is an exception as testing with one methodology
determined that the value of 2 is acceptable.  Details are in
the changelog for the patch "x86: mm: Change tlb_flushall_shift
for IvyBridge".

One important aspect of this to watch out for is Xen.  The
original commit log mentioned large performance gains on Xen.
It's possible Xen is more sensitive to this value if it flushes
small ranges of pages more frequently than workloads on bare
metal typically do.

Signed-off-by: Mel Gorman &lt;mgorman@suse.de&gt;
Tested-by: Davidlohr Bueso &lt;davidlohr@hp.com&gt;
Reviewed-by: Rik van Riel &lt;riel@redhat.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Cc: Alex Shi &lt;alex.shi@linaro.org&gt;
Cc: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Link: http://lkml.kernel.org/n/tip-dyzMww3fqugnhbhgo6Gxmtkw@git.kernel.org
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
There was a large ebizzy performance regression that was
bisected to commit 611ae8e3 (x86/tlb: enable tlb flush range
support for x86).  The problem was related to the
tlb_flushall_shift tuning for IvyBridge which was altered.  The
problem is that it is not clear if the tuning values for each
CPU family is correct as the methodology used to tune the values
is unclear.

This patch uses a conservative tlb_flushall_shift value for all
CPU families except IvyBridge so the decision can be revisited
if any regression is found as a result of this change.
IvyBridge is an exception as testing with one methodology
determined that the value of 2 is acceptable.  Details are in
the changelog for the patch "x86: mm: Change tlb_flushall_shift
for IvyBridge".

One important aspect of this to watch out for is Xen.  The
original commit log mentioned large performance gains on Xen.
It's possible Xen is more sensitive to this value if it flushes
small ranges of pages more frequently than workloads on bare
metal typically do.

Signed-off-by: Mel Gorman &lt;mgorman@suse.de&gt;
Tested-by: Davidlohr Bueso &lt;davidlohr@hp.com&gt;
Reviewed-by: Rik van Riel &lt;riel@redhat.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Cc: Alex Shi &lt;alex.shi@linaro.org&gt;
Cc: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Link: http://lkml.kernel.org/n/tip-dyzMww3fqugnhbhgo6Gxmtkw@git.kernel.org
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>x86: mm: change tlb_flushall_shift for IvyBridge</title>
<updated>2014-01-25T08:10:43+00:00</updated>
<author>
<name>Mel Gorman</name>
<email>mgorman@suse.de</email>
</author>
<published>2014-01-21T22:33:21+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=f98b7a772ab51b52ca4d2a14362fc0e0c8a2e0f3'/>
<id>f98b7a772ab51b52ca4d2a14362fc0e0c8a2e0f3</id>
<content type='text'>
There was a large performance regression that was bisected to
commit 611ae8e3 ("x86/tlb: enable tlb flush range support for
x86").  This patch simply changes the default balance point
between a local and global flush for IvyBridge.

In the interest of allowing the tests to be reproduced, this
patch was tested using mmtests 0.15 with the following
configurations

	configs/config-global-dhp__tlbflush-performance
	configs/config-global-dhp__scheduler-performance
	configs/config-global-dhp__network-performance

Results are from two machines

Ivybridge   4 threads:  Intel(R) Core(TM) i3-3240 CPU @ 3.40GHz
Ivybridge   8 threads:  Intel(R) Core(TM) i7-3770 CPU @ 3.40GHz

Page fault microbenchmark showed nothing interesting.

Ebizzy was configured to run multiple iterations and threads.
Thread counts ranged from 1 to NR_CPUS*2. For each thread count,
it ran 100 iterations and each iteration lasted 10 seconds.

Ivybridge 4 threads
                    3.13.0-rc7            3.13.0-rc7
                       vanilla           altshift-v3
Mean   1     6395.44 (  0.00%)     6789.09 (  6.16%)
Mean   2     7012.85 (  0.00%)     8052.16 ( 14.82%)
Mean   3     6403.04 (  0.00%)     6973.74 (  8.91%)
Mean   4     6135.32 (  0.00%)     6582.33 (  7.29%)
Mean   5     6095.69 (  0.00%)     6526.68 (  7.07%)
Mean   6     6114.33 (  0.00%)     6416.64 (  4.94%)
Mean   7     6085.10 (  0.00%)     6448.51 (  5.97%)
Mean   8     6120.62 (  0.00%)     6462.97 (  5.59%)

Ivybridge 8 threads
                     3.13.0-rc7            3.13.0-rc7
                        vanilla           altshift-v3
Mean   1      7336.65 (  0.00%)     7787.02 (  6.14%)
Mean   2      8218.41 (  0.00%)     9484.13 ( 15.40%)
Mean   3      7973.62 (  0.00%)     8922.01 ( 11.89%)
Mean   4      7798.33 (  0.00%)     8567.03 (  9.86%)
Mean   5      7158.72 (  0.00%)     8214.23 ( 14.74%)
Mean   6      6852.27 (  0.00%)     7952.45 ( 16.06%)
Mean   7      6774.65 (  0.00%)     7536.35 ( 11.24%)
Mean   8      6510.50 (  0.00%)     6894.05 (  5.89%)
Mean   12     6182.90 (  0.00%)     6661.29 (  7.74%)
Mean   16     6100.09 (  0.00%)     6608.69 (  8.34%)

Ebizzy hits the worst case scenario for TLB range flushing every
time and it shows for these Ivybridge CPUs at least that the
default choice is a poor on.  The patch addresses the problem.

Next was a tlbflush microbenchmark written by Alex Shi at
http://marc.info/?l=linux-kernel&amp;m=133727348217113 .  It
measures access costs while the TLB is being flushed.  The
expectation is that if there are always full TLB flushes that
the benchmark would suffer and it benefits from range flushing

There are 320 iterations of the test per thread count.  The
number of entries is randomly selected with a min of 1 and max
of 512.  To ensure a reasonably even spread of entries, the full
range is broken up into 8 sections and a random number selected
within that section.

iteration 1, random number between 0-64
iteration 2, random number between 64-128 etc

This is still a very weak methodology.  When you do not know
what are typical ranges, random is a reasonable choice but it
can be easily argued that the opimisation was for smaller ranges
and an even spread is not representative of any workload that
matters.  To improve this, we'd need to know the probability
distribution of TLB flush range sizes for a set of workloads
that are considered "common", build a synthetic trace and feed
that into this benchmark.  Even that is not perfect because it
would not account for the time between flushes but there are
limits of what can be reasonably done and still be doing
something useful.  If a representative synthetic trace is
provided then this benchmark could be revisited and the shift values retuned.

Ivybridge 4 threads
                        3.13.0-rc7            3.13.0-rc7
                           vanilla           altshift-v3
Mean       1       10.50 (  0.00%)       10.50 (  0.03%)
Mean       2       17.59 (  0.00%)       17.18 (  2.34%)
Mean       3       22.98 (  0.00%)       21.74 (  5.41%)
Mean       5       47.13 (  0.00%)       46.23 (  1.92%)
Mean       8       43.30 (  0.00%)       42.56 (  1.72%)

Ivybridge 8 threads
                         3.13.0-rc7            3.13.0-rc7
                            vanilla           altshift-v3
Mean       1         9.45 (  0.00%)        9.36 (  0.93%)
Mean       2         9.37 (  0.00%)        9.70 ( -3.54%)
Mean       3         9.36 (  0.00%)        9.29 (  0.70%)
Mean       5        14.49 (  0.00%)       15.04 ( -3.75%)
Mean       8        41.08 (  0.00%)       38.73 (  5.71%)
Mean       13       32.04 (  0.00%)       31.24 (  2.49%)
Mean       16       40.05 (  0.00%)       39.04 (  2.51%)

For both CPUs, average access time is reduced which is good as
this is the benchmark that was used to tune the shift values in
the first place albeit it is now known *how* the benchmark was
used.

The scheduler benchmarks were somewhat inconclusive.  They
showed gains and losses and makes me reconsider how stable those
benchmarks really are or if something else might be interfering
with the test results recently.

Network benchmarks were inconclusive.  Almost all results were
flat except for netperf-udp tests on the 4 thread machine.
These results were unstable and showed large variations between
reboots.  It is unknown if this is a recent problems but I've
noticed before that netperf-udp results tend to vary.

Based on these results, changing the default for Ivybridge seems
like a logical choice.

Signed-off-by: Mel Gorman &lt;mgorman@suse.de&gt;
Tested-by: Davidlohr Bueso &lt;davidlohr@hp.com&gt;
Reviewed-by: Alex Shi &lt;alex.shi@linaro.org&gt;
Reviewed-by: Rik van Riel &lt;riel@redhat.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Cc: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Link: http://lkml.kernel.org/n/tip-cqnadffh1tiqrshthRj3Esge@git.kernel.org
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
There was a large performance regression that was bisected to
commit 611ae8e3 ("x86/tlb: enable tlb flush range support for
x86").  This patch simply changes the default balance point
between a local and global flush for IvyBridge.

In the interest of allowing the tests to be reproduced, this
patch was tested using mmtests 0.15 with the following
configurations

	configs/config-global-dhp__tlbflush-performance
	configs/config-global-dhp__scheduler-performance
	configs/config-global-dhp__network-performance

Results are from two machines

Ivybridge   4 threads:  Intel(R) Core(TM) i3-3240 CPU @ 3.40GHz
Ivybridge   8 threads:  Intel(R) Core(TM) i7-3770 CPU @ 3.40GHz

Page fault microbenchmark showed nothing interesting.

Ebizzy was configured to run multiple iterations and threads.
Thread counts ranged from 1 to NR_CPUS*2. For each thread count,
it ran 100 iterations and each iteration lasted 10 seconds.

Ivybridge 4 threads
                    3.13.0-rc7            3.13.0-rc7
                       vanilla           altshift-v3
Mean   1     6395.44 (  0.00%)     6789.09 (  6.16%)
Mean   2     7012.85 (  0.00%)     8052.16 ( 14.82%)
Mean   3     6403.04 (  0.00%)     6973.74 (  8.91%)
Mean   4     6135.32 (  0.00%)     6582.33 (  7.29%)
Mean   5     6095.69 (  0.00%)     6526.68 (  7.07%)
Mean   6     6114.33 (  0.00%)     6416.64 (  4.94%)
Mean   7     6085.10 (  0.00%)     6448.51 (  5.97%)
Mean   8     6120.62 (  0.00%)     6462.97 (  5.59%)

Ivybridge 8 threads
                     3.13.0-rc7            3.13.0-rc7
                        vanilla           altshift-v3
Mean   1      7336.65 (  0.00%)     7787.02 (  6.14%)
Mean   2      8218.41 (  0.00%)     9484.13 ( 15.40%)
Mean   3      7973.62 (  0.00%)     8922.01 ( 11.89%)
Mean   4      7798.33 (  0.00%)     8567.03 (  9.86%)
Mean   5      7158.72 (  0.00%)     8214.23 ( 14.74%)
Mean   6      6852.27 (  0.00%)     7952.45 ( 16.06%)
Mean   7      6774.65 (  0.00%)     7536.35 ( 11.24%)
Mean   8      6510.50 (  0.00%)     6894.05 (  5.89%)
Mean   12     6182.90 (  0.00%)     6661.29 (  7.74%)
Mean   16     6100.09 (  0.00%)     6608.69 (  8.34%)

Ebizzy hits the worst case scenario for TLB range flushing every
time and it shows for these Ivybridge CPUs at least that the
default choice is a poor on.  The patch addresses the problem.

Next was a tlbflush microbenchmark written by Alex Shi at
http://marc.info/?l=linux-kernel&amp;m=133727348217113 .  It
measures access costs while the TLB is being flushed.  The
expectation is that if there are always full TLB flushes that
the benchmark would suffer and it benefits from range flushing

There are 320 iterations of the test per thread count.  The
number of entries is randomly selected with a min of 1 and max
of 512.  To ensure a reasonably even spread of entries, the full
range is broken up into 8 sections and a random number selected
within that section.

iteration 1, random number between 0-64
iteration 2, random number between 64-128 etc

This is still a very weak methodology.  When you do not know
what are typical ranges, random is a reasonable choice but it
can be easily argued that the opimisation was for smaller ranges
and an even spread is not representative of any workload that
matters.  To improve this, we'd need to know the probability
distribution of TLB flush range sizes for a set of workloads
that are considered "common", build a synthetic trace and feed
that into this benchmark.  Even that is not perfect because it
would not account for the time between flushes but there are
limits of what can be reasonably done and still be doing
something useful.  If a representative synthetic trace is
provided then this benchmark could be revisited and the shift values retuned.

Ivybridge 4 threads
                        3.13.0-rc7            3.13.0-rc7
                           vanilla           altshift-v3
Mean       1       10.50 (  0.00%)       10.50 (  0.03%)
Mean       2       17.59 (  0.00%)       17.18 (  2.34%)
Mean       3       22.98 (  0.00%)       21.74 (  5.41%)
Mean       5       47.13 (  0.00%)       46.23 (  1.92%)
Mean       8       43.30 (  0.00%)       42.56 (  1.72%)

Ivybridge 8 threads
                         3.13.0-rc7            3.13.0-rc7
                            vanilla           altshift-v3
Mean       1         9.45 (  0.00%)        9.36 (  0.93%)
Mean       2         9.37 (  0.00%)        9.70 ( -3.54%)
Mean       3         9.36 (  0.00%)        9.29 (  0.70%)
Mean       5        14.49 (  0.00%)       15.04 ( -3.75%)
Mean       8        41.08 (  0.00%)       38.73 (  5.71%)
Mean       13       32.04 (  0.00%)       31.24 (  2.49%)
Mean       16       40.05 (  0.00%)       39.04 (  2.51%)

For both CPUs, average access time is reduced which is good as
this is the benchmark that was used to tune the shift values in
the first place albeit it is now known *how* the benchmark was
used.

The scheduler benchmarks were somewhat inconclusive.  They
showed gains and losses and makes me reconsider how stable those
benchmarks really are or if something else might be interfering
with the test results recently.

Network benchmarks were inconclusive.  Almost all results were
flat except for netperf-udp tests on the 4 thread machine.
These results were unstable and showed large variations between
reboots.  It is unknown if this is a recent problems but I've
noticed before that netperf-udp results tend to vary.

Based on these results, changing the default for Ivybridge seems
like a logical choice.

Signed-off-by: Mel Gorman &lt;mgorman@suse.de&gt;
Tested-by: Davidlohr Bueso &lt;davidlohr@hp.com&gt;
Reviewed-by: Alex Shi &lt;alex.shi@linaro.org&gt;
Reviewed-by: Rik van Riel &lt;riel@redhat.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Cc: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Link: http://lkml.kernel.org/n/tip-cqnadffh1tiqrshthRj3Esge@git.kernel.org
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge branch 'x86-cpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip</title>
<updated>2014-01-20T20:04:45+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2014-01-20T20:04:45+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=5d4863e4cc4dc12d1d5e42da3cb5d38c535e4ad6'/>
<id>5d4863e4cc4dc12d1d5e42da3cb5d38c535e4ad6</id>
<content type='text'>
Pull x86 TLB detection update from Ingo Molnar:
 "A single change that extends our TLB cache size detection+reporting
  code"

* 'x86-cpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86, cpu: Detect more TLB configuration
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull x86 TLB detection update from Ingo Molnar:
 "A single change that extends our TLB cache size detection+reporting
  code"

* 'x86-cpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86, cpu: Detect more TLB configuration
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge branch 'x86-cleanups-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip</title>
<updated>2014-01-20T20:03:57+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2014-01-20T20:03:57+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=2a0fede97fd52a5c9789d1d54ebd3b46878151c3'/>
<id>2a0fede97fd52a5c9789d1d54ebd3b46878151c3</id>
<content type='text'>
Pull x86 cleanups from Ingo Molnar:
 "Misc cleanups"

* 'x86-cleanups-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86, cpu, amd: Fix a shadowed variable situation
  um, x86: Fix vDSO build
  x86: Delete non-required instances of include &lt;linux/init.h&gt;
  x86, realmode: Pointer walk cleanups, pull out invariant use of __pa()
  x86/traps: Clean up error exception handler definitions
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull x86 cleanups from Ingo Molnar:
 "Misc cleanups"

* 'x86-cleanups-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86, cpu, amd: Fix a shadowed variable situation
  um, x86: Fix vDSO build
  x86: Delete non-required instances of include &lt;linux/init.h&gt;
  x86, realmode: Pointer walk cleanups, pull out invariant use of __pa()
  x86/traps: Clean up error exception handler definitions
</pre>
</div>
</content>
</entry>
</feed>
