<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux.git/Documentation/scheduler, branch v3.10</title>
<subtitle>Linux kernel source tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/'/>
<entry>
<title>sched: Remove __ARCH_WANT_INTERRUPTS_ON_CTXSW</title>
<updated>2012-09-13T14:52:04+00:00</updated>
<author>
<name>Peter Zijlstra</name>
<email>a.p.zijlstra@chello.nl</email>
</author>
<published>2012-09-12T09:22:00+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=f3e947867478af9a12b9956bcd000ac7613a8a95'/>
<id>f3e947867478af9a12b9956bcd000ac7613a8a95</id>
<content type='text'>
Now that the last architecture to use this has stopped doing so (ARM,
thanks Catalin!) we can remove this complexity from the scheduler
core.

Signed-off-by: Peter Zijlstra &lt;a.p.zijlstra@chello.nl&gt;
Cc: Oleg Nesterov &lt;oleg@redhat.com&gt;
Cc: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Link: http://lkml.kernel.org/n/tip-g9p2a1w81xxbrze25v9zpzbf@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>
Now that the last architecture to use this has stopped doing so (ARM,
thanks Catalin!) we can remove this complexity from the scheduler
core.

Signed-off-by: Peter Zijlstra &lt;a.p.zijlstra@chello.nl&gt;
Cc: Oleg Nesterov &lt;oleg@redhat.com&gt;
Cc: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Link: http://lkml.kernel.org/n/tip-g9p2a1w81xxbrze25v9zpzbf@git.kernel.org
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>sched: Remove stale power aware scheduling remnants and dysfunctional knobs</title>
<updated>2012-05-17T11:48:56+00:00</updated>
<author>
<name>Peter Zijlstra</name>
<email>peterz@infradead.org</email>
</author>
<published>2012-01-09T10:28:35+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=8e7fbcbc22c12414bcc9dfdd683637f58fb32759'/>
<id>8e7fbcbc22c12414bcc9dfdd683637f58fb32759</id>
<content type='text'>
It's been broken forever (i.e. it's not scheduling in a power
aware fashion), as reported by Suresh and others sending
patches, and nobody cares enough to fix it properly ...
so remove it to make space free for something better.

There's various problems with the code as it stands today, first
and foremost the user interface which is bound to topology
levels and has multiple values per level. This results in a
state explosion which the administrator or distro needs to
master and almost nobody does.

Furthermore large configuration state spaces aren't good, it
means the thing doesn't just work right because it's either
under so many impossibe to meet constraints, or even if
there's an achievable state workloads have to be aware of
it precisely and can never meet it for dynamic workloads.

So pushing this kind of decision to user-space was a bad idea
even with a single knob - it's exponentially worse with knobs
on every node of the topology.

There is a proposal to replace the user interface with a single
3 state knob:

 sched_balance_policy := { performance, power, auto }

where 'auto' would be the preferred default which looks at things
like Battery/AC mode and possible cpufreq state or whatever the hw
exposes to show us power use expectations - but there's been no
progress on it in the past many months.

Aside from that, the actual implementation of the various knobs
is known to be broken. There have been sporadic attempts at
fixing things but these always stop short of reaching a mergable
state.

Therefore this wholesale removal with the hopes of spurring
people who care to come forward once again and work on a
coherent replacement.

Signed-off-by: Peter Zijlstra &lt;a.p.zijlstra@chello.nl&gt;
Cc: Suresh Siddha &lt;suresh.b.siddha@intel.com&gt;
Cc: Arjan van de Ven &lt;arjan@linux.intel.com&gt;
Cc: Vincent Guittot &lt;vincent.guittot@linaro.org&gt;
Cc: Vaidyanathan Srinivasan &lt;svaidy@linux.vnet.ibm.com&gt;
Cc: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Link: http://lkml.kernel.org/r/1326104915.2442.53.camel@twins
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
It's been broken forever (i.e. it's not scheduling in a power
aware fashion), as reported by Suresh and others sending
patches, and nobody cares enough to fix it properly ...
so remove it to make space free for something better.

There's various problems with the code as it stands today, first
and foremost the user interface which is bound to topology
levels and has multiple values per level. This results in a
state explosion which the administrator or distro needs to
master and almost nobody does.

Furthermore large configuration state spaces aren't good, it
means the thing doesn't just work right because it's either
under so many impossibe to meet constraints, or even if
there's an achievable state workloads have to be aware of
it precisely and can never meet it for dynamic workloads.

So pushing this kind of decision to user-space was a bad idea
even with a single knob - it's exponentially worse with knobs
on every node of the topology.

There is a proposal to replace the user interface with a single
3 state knob:

 sched_balance_policy := { performance, power, auto }

where 'auto' would be the preferred default which looks at things
like Battery/AC mode and possible cpufreq state or whatever the hw
exposes to show us power use expectations - but there's been no
progress on it in the past many months.

Aside from that, the actual implementation of the various knobs
is known to be broken. There have been sporadic attempts at
fixing things but these always stop short of reaching a mergable
state.

Therefore this wholesale removal with the hopes of spurring
people who care to come forward once again and work on a
coherent replacement.

Signed-off-by: Peter Zijlstra &lt;a.p.zijlstra@chello.nl&gt;
Cc: Suresh Siddha &lt;suresh.b.siddha@intel.com&gt;
Cc: Arjan van de Ven &lt;arjan@linux.intel.com&gt;
Cc: Vincent Guittot &lt;vincent.guittot@linaro.org&gt;
Cc: Vaidyanathan Srinivasan &lt;svaidy@linux.vnet.ibm.com&gt;
Cc: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Link: http://lkml.kernel.org/r/1326104915.2442.53.camel@twins
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>sched: Update documentation and comments</title>
<updated>2012-05-07T13:04:18+00:00</updated>
<author>
<name>Hiroshi Shimamoto</name>
<email>h-shimamoto@ct.jp.nec.com</email>
</author>
<published>2012-04-02T08:00:44+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=489a71b029cd94e3b0132795146e8be3a87bf3fa'/>
<id>489a71b029cd94e3b0132795146e8be3a87bf3fa</id>
<content type='text'>
Change sched_*.c to sched/*.c in documentation and comments.

Signed-off-by: Hiroshi Shimamoto &lt;h-shimamoto@ct.jp.nec.com&gt;
Cc: Peter Zijlstra &lt;a.p.zijlstra@chello.nl&gt;
Link: http://lkml.kernel.org/r/4F795CAC.9080206@ct.jp.nec.com
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Change sched_*.c to sched/*.c in documentation and comments.

Signed-off-by: Hiroshi Shimamoto &lt;h-shimamoto@ct.jp.nec.com&gt;
Cc: Peter Zijlstra &lt;a.p.zijlstra@chello.nl&gt;
Link: http://lkml.kernel.org/r/4F795CAC.9080206@ct.jp.nec.com
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>sched: Remove sched_switch</title>
<updated>2012-01-27T12:28:53+00:00</updated>
<author>
<name>Rakib Mullick</name>
<email>rakib.mullick@gmail.com</email>
</author>
<published>2012-01-24T16:33:56+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=30fd049afcfed50e022704036e8629d6bdfe84e6'/>
<id>30fd049afcfed50e022704036e8629d6bdfe84e6</id>
<content type='text'>
Currently we don't utilize the sched_switch field anymore.

But, simply removing sched_switch field from the middle of the
sched_stat output will break tools.

So, to stay compatible we hardcode it to zero and remove the
field from the scheduler data structures.

Update the schedstat documentation accordingly.

Signed-off-by: Rakib Mullick &lt;rakib.mullick@gmail.com&gt;
Signed-off-by: Peter Zijlstra &lt;a.p.zijlstra@chello.nl&gt;
Link: http://lkml.kernel.org/r/1327422836.27181.5.camel@localhost.localdomain
Signed-off-by: Ingo Molnar &lt;mingo@elte.hu&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Currently we don't utilize the sched_switch field anymore.

But, simply removing sched_switch field from the middle of the
sched_stat output will break tools.

So, to stay compatible we hardcode it to zero and remove the
field from the scheduler data structures.

Update the schedstat documentation accordingly.

Signed-off-by: Rakib Mullick &lt;rakib.mullick@gmail.com&gt;
Signed-off-by: Peter Zijlstra &lt;a.p.zijlstra@chello.nl&gt;
Link: http://lkml.kernel.org/r/1327422836.27181.5.camel@localhost.localdomain
Signed-off-by: Ingo Molnar &lt;mingo@elte.hu&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>sched: Add documentation for bandwidth control</title>
<updated>2011-08-14T10:03:58+00:00</updated>
<author>
<name>Bharata B Rao</name>
<email>bharata@linux.vnet.ibm.com</email>
</author>
<published>2011-07-21T16:43:43+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=88ebc08ea9f721d1345d5414288a308ea42ac458'/>
<id>88ebc08ea9f721d1345d5414288a308ea42ac458</id>
<content type='text'>
Basic description of usage and effect for CFS Bandwidth Control.

Signed-off-by: Bharata B Rao &lt;bharata@linux.vnet.ibm.com&gt;
Signed-off-by: Paul Turner &lt;pjt@google.com&gt;
Signed-off-by: Peter Zijlstra &lt;a.p.zijlstra@chello.nl&gt;
Link: http://lkml.kernel.org/r/20110721184758.498036116@google.com
Signed-off-by: Ingo Molnar &lt;mingo@elte.hu&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Basic description of usage and effect for CFS Bandwidth Control.

Signed-off-by: Bharata B Rao &lt;bharata@linux.vnet.ibm.com&gt;
Signed-off-by: Paul Turner &lt;pjt@google.com&gt;
Signed-off-by: Peter Zijlstra &lt;a.p.zijlstra@chello.nl&gt;
Link: http://lkml.kernel.org/r/20110721184758.498036116@google.com
Signed-off-by: Ingo Molnar &lt;mingo@elte.hu&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge branch 'master' into for-next</title>
<updated>2011-07-11T12:15:55+00:00</updated>
<author>
<name>Jiri Kosina</name>
<email>jkosina@suse.cz</email>
</author>
<published>2011-07-11T12:15:48+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=b7e9c223be8ce335e30f2cf6ba588e6a4092275c'/>
<id>b7e9c223be8ce335e30f2cf6ba588e6a4092275c</id>
<content type='text'>
Sync with Linus' tree to be able to apply pending patches that
are based on newer code already present upstream.
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Sync with Linus' tree to be able to apply pending patches that
are based on newer code already present upstream.
</pre>
</div>
</content>
</entry>
<entry>
<title>Documentation: update cgroupfs mount point</title>
<updated>2011-06-16T04:52:50+00:00</updated>
<author>
<name>Jörg Sommer</name>
<email>joerg@alea.gnuu.de</email>
</author>
<published>2011-06-15T19:59:45+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=f6e07d38078e82a6aeaae00bb134591ef5ac1167'/>
<id>f6e07d38078e82a6aeaae00bb134591ef5ac1167</id>
<content type='text'>
According to commit 676db4af0430 ("cgroupfs: create /sys/fs/cgroup to
mount cgroupfs on") the canonical mountpoint for the cgroup filesystem
is /sys/fs/cgroup.  Hence, this should be used in the documentation.

Signed-off-by: Jörg Sommer &lt;joerg@alea.gnuu.de&gt;
Acked-by: Paul Menage &lt;menage@google.com&gt;
Signed-off-by: Randy Dunlap &lt;randy.dunlap@oracle.com&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
According to commit 676db4af0430 ("cgroupfs: create /sys/fs/cgroup to
mount cgroupfs on") the canonical mountpoint for the cgroup filesystem
is /sys/fs/cgroup.  Hence, this should be used in the documentation.

Signed-off-by: Jörg Sommer &lt;joerg@alea.gnuu.de&gt;
Acked-by: Paul Menage &lt;menage@google.com&gt;
Signed-off-by: Randy Dunlap &lt;randy.dunlap@oracle.com&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>doc: fix wrong arch/i386 references</title>
<updated>2011-06-13T11:43:05+00:00</updated>
<author>
<name>Wanlong Gao</name>
<email>wanlong.gao@gmail.com</email>
</author>
<published>2011-06-13T09:53:53+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=25eb650a690b95cb0e2cf0c3b03f4900a59e0135'/>
<id>25eb650a690b95cb0e2cf0c3b03f4900a59e0135</id>
<content type='text'>
Change all "arch/i386" to "arch/x86" in Documentaion/,
since the directory has changed.

Also update the files which have changed their filename
in the meantime accordingly.

Signed-off-by: Wanlong Gao &lt;wanlong.gao@gmail.com&gt;
[jkosina@suse.cz: reword changelog]
Signed-off-by: Jiri Kosina &lt;jkosina@suse.cz&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Change all "arch/i386" to "arch/x86" in Documentaion/,
since the directory has changed.

Also update the files which have changed their filename
in the meantime accordingly.

Signed-off-by: Wanlong Gao &lt;wanlong.gao@gmail.com&gt;
[jkosina@suse.cz: reword changelog]
Signed-off-by: Jiri Kosina &lt;jkosina@suse.cz&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>sched, doc: Beef up load balancing description</title>
<updated>2011-03-31T11:00:35+00:00</updated>
<author>
<name>Borislav Petkov</name>
<email>bp@alien8.de</email>
</author>
<published>2011-03-27T15:57:13+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=e2495b577324938f0209b4f895c5f205c7e47854'/>
<id>e2495b577324938f0209b4f895c5f205c7e47854</id>
<content type='text'>
Correct all function names pertaining to load balancing and explain
shortly how load balancing is performed.

Signed-off-by: Borislav Petkov &lt;bp@alien8.de&gt;
Signed-off-by: Peter Zijlstra &lt;a.p.zijlstra@chello.nl&gt;
LKML-Reference: &lt;1301241433-3790-1-git-send-email-bp@alien8.de&gt;
Signed-off-by: Ingo Molnar &lt;mingo@elte.hu&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Correct all function names pertaining to load balancing and explain
shortly how load balancing is performed.

Signed-off-by: Borislav Petkov &lt;bp@alien8.de&gt;
Signed-off-by: Peter Zijlstra &lt;a.p.zijlstra@chello.nl&gt;
LKML-Reference: &lt;1301241433-3790-1-git-send-email-bp@alien8.de&gt;
Signed-off-by: Ingo Molnar &lt;mingo@elte.hu&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>sched, doc: Update sched-design-CFS.txt</title>
<updated>2011-03-23T13:09:41+00:00</updated>
<author>
<name>Borislav Petkov</name>
<email>borislav.petkov@amd.com</email>
</author>
<published>2011-03-22T17:46:18+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=1232d6132a986125f6a687ab9b61a4330e319270'/>
<id>1232d6132a986125f6a687ab9b61a4330e319270</id>
<content type='text'>
Correct -&gt;dequeue_tree() thinko into sched_class-&gt;dequeue_task
and drop all references to -&gt;task_new() since it is obviously
gone.

Signed-off-by: Borislav Petkov &lt;borislav.petkov@amd.com&gt;
Cc: Peter Zijlstra &lt;a.p.zijlstra@chello.nl&gt;
Cc: Mike Galbraith &lt;efault@gmx.de&gt;
LKML-Reference: &lt;1300815978-16618-1-git-send-email-bp@amd64.org&gt;
Signed-off-by: Ingo Molnar &lt;mingo@elte.hu&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Correct -&gt;dequeue_tree() thinko into sched_class-&gt;dequeue_task
and drop all references to -&gt;task_new() since it is obviously
gone.

Signed-off-by: Borislav Petkov &lt;borislav.petkov@amd.com&gt;
Cc: Peter Zijlstra &lt;a.p.zijlstra@chello.nl&gt;
Cc: Mike Galbraith &lt;efault@gmx.de&gt;
LKML-Reference: &lt;1300815978-16618-1-git-send-email-bp@amd64.org&gt;
Signed-off-by: Ingo Molnar &lt;mingo@elte.hu&gt;
</pre>
</div>
</content>
</entry>
</feed>
