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2018-10-24Merge tag 'docs-4.20' of git://git.lwn.net/linuxLinus Torvalds
Pull documentation updates from Jonathan Corbet: "This is a fairly typical cycle for documentation. There's some welcome readability improvements for the formatted output, some LICENSES updates including the addition of the ISC license, the removal of the unloved and unmaintained 00-INDEX files, the deprecated APIs document from Kees, more MM docs from Mike Rapoport, and the usual pile of typo fixes and corrections" * tag 'docs-4.20' of git://git.lwn.net/linux: (41 commits) docs: Fix typos in histogram.rst docs: Introduce deprecated APIs list kernel-doc: fix declaration type determination doc: fix a typo in adding-syscalls.rst docs/admin-guide: memory-hotplug: remove table of contents doc: printk-formats: Remove bogus kobject references for device nodes Documentation: preempt-locking: Use better example dm flakey: Document "error_writes" feature docs/completion.txt: Fix a couple of punctuation nits LICENSES: Add ISC license text LICENSES: Add note to CDDL-1.0 license that it should not be used docs/core-api: memory-hotplug: add some details about locking internals docs/core-api: rename memory-hotplug-notifier to memory-hotplug docs: improve readability for people with poorer eyesight yama: clarify ptrace_scope=2 in Yama documentation docs/vm: split memory hotplug notifier description to Documentation/core-api docs: move memory hotplug description into admin-guide/mm doc: Fix acronym "FEKEK" in ecryptfs docs: fix some broken documentation references iommu: Fix passthrough option documentation ...
2018-10-17sched/completions/Documentation: Add recommendation for dynamic and ONSTACK ↵Nicholas Mc Guire
completions To prevent dynamic completion objects from being de-allocated while still in use, add a recommendation to embed them in long lived data structures. Also add a note for the on-stack case that emphasizes the dangers of the limited scope, and recommends dynamic allocation if scope limitations are not clearly understood. [ mingo: Minor touch-ups of the text, expanded it a bit to make the warnings Nicholas added more prominent. ] Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: john.garry@huawei.com Link: http://lkml.kernel.org/r/1539697539-24055-1-git-send-email-hofrat@osadl.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-10-12docs/completion.txt: Fix a couple of punctuation nitsJohn Garry
This patch fixes a couple of punctuation nits which can make the document more correct and readable. Also missing "()" are added to some function references for consistency. Signed-off-by: John Garry <john.garry@huawei.com> Acked-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2018-10-11sched/completions/Documentation: Clean up the document some moreIngo Molnar
Refresh the document: - Remove unnecessary liguistic complexity and improve the clarity of the text - Improve the explanations all around - Remove unnecessary and stale version info - Fix whitespace noise - Make pseudo-code match kernel style - Fix minor syntax errors in pseudo-code - Use consistent denotation - Mark multi-CPU sequences more explicitly - Unbreak line breaks - Use quotes to refer to 'struct completion' - Use 'IRQ context' and 'IRQs' consistently - Improve grammar - etc. Cc: John Garry <john.garry@huawei.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Nicholas Mc Guire <hofrat@osadl.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: corbet@lwn.net Cc: linux-doc@vger.kernel.org Link: http://lkml.kernel.org/r/1539183392-239389-1-git-send-email-john.garry@huawei.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-10-11sched/completions/Documentation: Fix a couple of punctuation nitsJohn Garry
This patch fixes a couple of punctuation nits which can make the document more correct and readable. Also missing "()" are added to some function references for consistency. Signed-off-by: John Garry <john.garry@huawei.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: corbet@lwn.net Cc: linux-doc@vger.kernel.org Link: http://lkml.kernel.org/r/1539183392-239389-1-git-send-email-john.garry@huawei.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-09-09Drop all 00-INDEX files from Documentation/Henrik Austad
This is a respin with a wider audience (all that get_maintainer returned) and I know this spams a *lot* of people. Not sure what would be the correct way, so my apologies for ruining your inbox. The 00-INDEX files are supposed to give a summary of all files present in a directory, but these files are horribly out of date and their usefulness is brought into question. Often a simple "ls" would reveal the same information as the filenames are generally quite descriptive as a short introduction to what the file covers (it should not surprise anyone what Documentation/sched/sched-design-CFS.txt covers) A few years back it was mentioned that these files were no longer really needed, and they have since then grown further out of date, so perhaps it is time to just throw them out. A short status yields the following _outdated_ 00-INDEX files, first counter is files listed in 00-INDEX but missing in the directory, last is files present but not listed in 00-INDEX. List of outdated 00-INDEX: Documentation: (4/10) Documentation/sysctl: (0/1) Documentation/timers: (1/0) Documentation/blockdev: (3/1) Documentation/w1/slaves: (0/1) Documentation/locking: (0/1) Documentation/devicetree: (0/5) Documentation/power: (1/1) Documentation/powerpc: (0/5) Documentation/arm: (1/0) Documentation/x86: (0/9) Documentation/x86/x86_64: (1/1) Documentation/scsi: (4/4) Documentation/filesystems: (2/9) Documentation/filesystems/nfs: (0/2) Documentation/cgroup-v1: (0/2) Documentation/kbuild: (0/4) Documentation/spi: (1/0) Documentation/virtual/kvm: (1/0) Documentation/scheduler: (0/2) Documentation/fb: (0/1) Documentation/block: (0/1) Documentation/networking: (6/37) Documentation/vm: (1/3) Then there are 364 subdirectories in Documentation/ with several files that are missing 00-INDEX alltogether (and another 120 with a single file and no 00-INDEX). I don't really have an opinion to whether or not we /should/ have 00-INDEX, but the above 00-INDEX should either be removed or be kept up to date. If we should keep the files, I can try to keep them updated, but I rather not if we just want to delete them anyway. As a starting point, remove all index-files and references to 00-INDEX and see where the discussion is going. Signed-off-by: Henrik Austad <henrik@austad.us> Acked-by: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Just-do-it-by: Steven Rostedt <rostedt@goodmis.org> Reviewed-by: Jens Axboe <axboe@kernel.dk> Acked-by: Paul Moore <paul@paul-moore.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Acked-by: Mark Brown <broonie@kernel.org> Acked-by: Mike Rapoport <rppt@linux.vnet.ibm.com> Cc: [Almost everybody else] Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2018-05-14sched/deadline/Documentation: Add overrun signal and GRUB-PA documentationClaudio Scordino
Signed-off-by: Claudio Scordino <claudio@evidence.eu.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Juri Lelli <juri.lelli@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Luca Abeni <luca.abeni@santannapisa.it> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Link: http://lkml.kernel.org/r/1522741362-4542-1-git-send-email-claudio@evidence.eu.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-11-16sched/deadline: Fix the description of runtime accounting in the documentationClaudio Scordino
Signed-off-by: Claudio Scordino <claudio@evidence.eu.com> Signed-off-by: Luca Abeni <luca.abeni@santannapisa.it> Acked-by: Daniel Bristot de Oliveira <bristot@redhat.com> Acked-by: Peter Zijlstra <peterz@infradead.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mathieu Poirier <mathieu.poirier@linaro.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tommaso Cucinotta <tommaso.cucinotta@sssup.it> Cc: linux-doc@vger.kernel.org Link: http://lkml.kernel.org/r/1510658366-28995-1-git-send-email-claudio@evidence.eu.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-06-08sched/deadline: Add documentation about GRUB reclaimingClaudio Scordino
This patch adds the documentation about the GRUB reclaiming algorithm, adding a few details discussed in list. Signed-off-by: Claudio Scordino <claudio@evidence.eu.com> Signed-off-by: Luca Abeni <luca.abeni@santannapisa.it> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Daniel Bristot de Oliveira <bristot@redhat.com> Cc: Joel Fernandes <joelaf@google.com> Cc: Juri Lelli <juri.lelli@arm.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mathieu Poirier <mathieu.poirier@linaro.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tommaso Cucinotta <tommaso.cucinotta@sssup.it> Link: http://lkml.kernel.org/r/1495138417-6203-11-git-send-email-luca.abeni@santannapisa.it Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-04-14sched/Documentation: Add 'sched-pelt' toolYuyang Du
Add a user-space program to compute/generate the PELT constants. The kernel/sched/sched-pelt.h header will contain the output of this program. Signed-off-by: Yuyang Du <yuyang.du@intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: bsegall@google.com Cc: dietmar.eggemann@arm.com Cc: matt@codeblueprint.co.uk Cc: morten.rasmussen@arm.com Cc: pjt@google.com Cc: umgwanakikbuti@gmail.com Cc: vincent.guittot@linaro.org Link: http://lkml.kernel.org/r/1486935863-25251-2-git-send-email-yuyang.du@intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-01-22sched/Documentation/sched-rt-group: Fix incorrect exampleZhou Chengming
I feel that the example given in the document to show the possibility of task starvation of configurable period is wrong. The example says group A and B both have 50% bandwidth, and a while (1) loop in A will run for the full period of B and can starve B's tasks. So I think the runtime of group A should be 50000us, then the period and runtime of group B should be 50000us and 25000us. Signed-off-by: Zhou Chengming <zhouchengming1@huawei.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: corbet@lwn.net Cc: iamyooon@gmail.com Cc: linux-doc@vger.kernel.org Cc: lizefan@huawei.com Link: http://lkml.kernel.org/r/1485069755-44287-1-git-send-email-zhouchengming1@huawei.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-01-14sched/deadline: Show leftover runtime and abs deadline in /proc/*/schedTommaso Cucinotta
This patch allows for reading the current (leftover) runtime and absolute deadline of a SCHED_DEADLINE task through /proc/*/sched (entries dl.runtime and dl.deadline), while debugging/testing. Signed-off-by: Tommaso Cucinotta <tommaso.cucinotta@sssup.it> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Juri Lelli <juri.lelli@arm.com> Reviewed-by: Luca Abeni <luca.abeni@unitn.it> Acked-by: Daniel Bistrot de Oliveira <danielbristot@gmail.com> Cc: Juri Lelli <juri.lelli@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1477473437-10346-2-git-send-email-tommaso.cucinotta@sssup.it Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-11-16docs/completion.txt: drop dangling reference to completions-design.txtBrian Norris
Per the original author, the proposed document was never deemed necessary, and the important bits got merged into completion.txt. Let's just stop confusing readers by pointing at a nonexistent doc. Signed-off-by: Brian Norris <briannorris@chromium.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2016-09-10sched/deadline: Document behavior of sched_yield()Tommaso Cucinotta
This is a documentation only patch, explaining the behavior of sched_yield() when a SCHED_DEADLINE task calls it (give up remaining runtime and be throttled until next period begins). Signed-off-by: Tommaso Cucinotta <tommaso.cucinotta@sssup.it> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Juri Lelli <juri.lelli@arm.com> Reviewed-by: Luca Abeni <luca.abeni@unitn.it> Reviewed-by: Daniel Bristot de Oliveira <bristot@redhat.com> Cc: Juri Lelli <juri.lelli@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-dl@retis.sssup.it Link: http://lkml.kernel.org/r/1473443117-11794-2-git-send-email-tommaso.cucinotta@sssup.it Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-08-03Documenation: update cgroup's document pathseokhoon.yoon
cgroup's document path is changed to "cgroup-v1". update it. Signed-off-by: seokhoon.yoon <iamyooon@gmail.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2015-05-19sched/dl/Documentation: Split Section 3Luca Abeni
Introduce 4 subsections to make Section 3 more readable. Signed-off-by: Luca Abeni <luca.abeni@unitn.it> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: henrik@austad.us Cc: juri.lelli@gmail.com Cc: raistlin@linux.it Link: http://lkml.kernel.org/r/1431954032-16473-10-git-send-email-luca.abeni@unitn.it Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-19sched/dl/Documentation: Clarify the relationship between tasks' deadlines ↵Luca Abeni
and absolute scheduling deadlines Clarify what is the relationship between tasks' parameters and scheduling parameters, explaining how to set the scheduling parameters so that all the absolute deadlines of a task are respected. Signed-off-by: Luca Abeni <luca.abeni@unitn.it> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: henrik@austad.us Cc: juri.lelli@gmail.com Cc: raistlin@linux.it Link: http://lkml.kernel.org/r/1431954032-16473-9-git-send-email-luca.abeni@unitn.it Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-19sched/dl/Documentation: Add some referencesLuca Abeni
Add a description of the Dhall's effect, some discussion about schedulability tests for global EDF, and references to real-time literature. Signed-off-by: Luca Abeni <luca.abeni@unitn.it> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: henrik@austad.us Cc: juri.lelli@gmail.com Cc: raistlin@linux.it Link: http://lkml.kernel.org/r/1431954032-16473-8-git-send-email-luca.abeni@unitn.it Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-19sched/dl/Documentation: Add some notes on EDF schedulabilityLuca Abeni
Add a short discussion about sufficient and necessary schedulability tests, and add a simple example showing that if D_i != P_i then density based tests are only sufficient. Also add some references to scientific papers on schedulability tests for EDF that are both necessary and sufficient, and on their computational complexity. Signed-off-by: Luca Abeni <luca.abeni@unitn.it> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: henrik@austad.us Cc: juri.lelli@gmail.com Cc: raistlin@linux.it Link: http://lkml.kernel.org/r/1431954032-16473-7-git-send-email-luca.abeni@unitn.it Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-19sched/dl/Documentation: Clarify indexing notationLuca Abeni
The "_i" index is used in this document to to denote a particular task, so "sum_i", "max_i" and "min_i" might be confusing. Signed-off-by: Luca Abeni <luca.abeni@unitn.it> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: henrik@austad.us Cc: juri.lelli@gmail.com Cc: raistlin@linux.it Link: http://lkml.kernel.org/r/1431954032-16473-6-git-send-email-luca.abeni@unitn.it Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-19sched/dl/Documentation: Use consistent namingLuca Abeni
The name "C_i" was used (without previously defining it) instead of "WCET_i". Signed-off-by: Luca Abeni <luca.abeni@unitn.it> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: henrik@austad.us Cc: juri.lelli@gmail.com Cc: raistlin@linux.it Link: http://lkml.kernel.org/r/1431954032-16473-5-git-send-email-luca.abeni@unitn.it Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-19sched/dl/Documentation: Fix typosLuca Abeni
Signed-off-by: Luca Abeni <luca.abeni@unitn.it> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: henrik@austad.us Cc: juri.lelli@gmail.com Cc: raistlin@linux.it Link: http://lkml.kernel.org/r/1431954032-16473-4-git-send-email-luca.abeni@unitn.it Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-19sched/dl/Documentation: Switch to American EnglishLuca Abeni
This file previously mixed American and British English; switch to American for consistency. Signed-off-by: Luca Abeni <luca.abeni@unitn.it> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: henrik@austad.us Cc: juri.lelli@gmail.com Cc: raistlin@linux.it Link: http://lkml.kernel.org/r/1431954032-16473-3-git-send-email-luca.abeni@unitn.it Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-19sched/dl/Documentation: Correct the definition of density as C_i/min{D_i,P_i}Zhiqiang Zhang
C_i/min{D_i,T_i}, where T_i is not referred before, should be substituted with C_i/min{D_i,P_i}. Signed-off-by: Zhiqiang Zhang <zhangzhiqiang.zhang@huawei.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: henrik@austad.us Cc: juri.lelli@gmail.com Cc: raistlin@linux.it Link: http://lkml.kernel.org/r/1431954032-16473-2-git-send-email-luca.abeni@unitn.it Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-04-04docs/completion.txt: Various tweaks and correctionsJonathan Corbet
Mostly language improvements to the new completions.txt document, but there is also a semantic correction in the description of completion_done() at the very end. Acked-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2015-04-04doc: completion: context, scope and language fixesNicholas Mc Guire
Fix for imprecise/wrong statements on context in which wait_for_completion*() can be called, updated notes on "going out of scope" problems and some language fixups. Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org> Acked-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2015-01-30doc: brief user documentation for completionNicholas Mc Guire
Signed-off-by: Nicholas Mc Guire <der.herr@hofr.at> [jc: cleaned up some spurious blank lines] Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2014-09-16Documentation/scheduler/sched-deadline.txt: Add minimal main() appendixJuri Lelli
Add an appendix providing a simple self-contained code snippet showing how SCHED_DEADLINE reservations can be created by application developers. Signed-off-by: Juri Lelli <juri.lelli@arm.com> Reviewed-by: Henrik Austad <henrik@austad.us> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Dario Faggioli <raistlin@linux.it> Cc: Juri Lelli <juri.lelli@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/r/1410256636-26171-6-git-send-email-juri.lelli@arm.com [ Fixed some whitespace inconsistencies. ] Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-09-16Documentation/scheduler/sched-deadline.txt: Add tests suite appendixJuri Lelli
Add an appendix briefly describing tools that can be used to test SCHED_DEADLINE (and the scheduler in general). Links to where source code of the tools is hosted are also provided. Signed-off-by: Juri Lelli <juri.lelli@arm.com> Reviewed-by: Henrik Austad <henrik@austad.us> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Dario Faggioli <raistlin@linux.it> Cc: Juri Lelli <juri.lelli@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/r/1410256636-26171-5-git-send-email-juri.lelli@arm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-09-16Documentation/scheduler/sched-deadline.txt: Improve and clarify AC bitsLuca Abeni
Admission control is of key importance for SCHED_DEADLINE, since it guarantees system schedulability (or tells us something about the degree of guarantees we can provide to the user). This patch improves and clarifies bits and pieces regarding AC, both for UP and SMP systems. Signed-off-by: Luca Abeni <luca.abeni@unitn.it> Signed-off-by: Juri Lelli <juri.lelli@arm.com> Reviewed-by: Henrik Austad <henrik@austad.us> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Dario Faggioli <raistlin@linux.it> Cc: Juri Lelli <juri.lelli@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/r/1410256636-26171-4-git-send-email-juri.lelli@arm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-09-16Documentation/scheduler/sched-deadline.txt: Rewrite section 4 introJuri Lelli
Section 4 intro was still describing the old interface. Rewrite it. Signed-off-by: Juri Lelli <juri.lelli@arm.com> Signed-off-by: Luca Abeni <luca.abeni@unitn.it> Reviewed-by: Henrik Austad <henrik@austad.us> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Dario Faggioli <raistlin@linux.it> Cc: Juri Lelli <juri.lelli@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/r/1410256636-26171-3-git-send-email-juri.lelli@arm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-09-16Documentation/scheduler/sched-deadline.txt: Fix terminology and improve clarityLuca Abeni
Several small changes regarding SCHED_DEADLINE documentation that fix terminology and improve clarity and readability: - "current runtime" becomes "remaining runtime" - readablity of an equation is improved by introducing more spacing - clarify when admission control will certainly fail - new URL for CBS technical report - substitue "smallest" with "earliest" Signed-off-by: Luca Abeni <luca.abeni@unitn.it> Signed-off-by: Juri Lelli <juri.lelli@arm.com> Reviewed-by: Henrik Austad <henrik@austad.us> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Dario Faggioli <raistlin@linux.it> Cc: Juri Lelli <juri.lelli@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/r/1410256636-26171-2-git-send-email-juri.lelli@arm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-04-07asm/system.h: clean asm/system.h from docsDavid Howells
Clean asm/system.h from docs as nothing should refer to that header anymore. Signed-off-by: David Howells <dhowells@redhat.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-02-10Documentation/: update 00-INDEX filesHenrik Austad
Some of the 00-INDEX files are somewhat outdated and some folders does not contain 00-INDEX at all. Only outdated (with the notably exception of spi) indexes are touched here, the 169 folders without 00-INDEX has not been touched. New 00-INDEX - spi/* was added in a series of commits dating back to 2006 Added files (missing in (*/)00-INDEX) - dmatest.txt was added by commit 851b7e16a07d ("dmatest: run test via debugfs") - this_cpu_ops.txt was added by commit a1b2a555d637 ("percpu: add documentation on this_cpu operations") - ww-mutex-design.txt was added by commit 040a0a371005 ("mutex: Add support for wound/wait style locks") - bcache.txt was added by commit cafe56359144 ("bcache: A block layer cache") - kernel-per-CPU-kthreads.txt was added by commit 49717cb40410 ("kthread: Document ways of reducing OS jitter due to per-CPU kthreads") - phy.txt was added by commit ff764963479a ("drivers: phy: add generic PHY framework") - block/null_blk was added by commit 12f8f4fc0314 ("null_blk: documentation") - module-signing.txt was added by commit 3cafea307642 ("Add Documentation/module-signing.txt file") - assoc_array.txt was added by commit 3cb989501c26 ("Add a generic associative array implementation.") - arm/IXP4xx was part of the initial repo - arm/cluster-pm-race-avoidance.txt was added by commit 7fe31d28e839 ("ARM: mcpm: introduce helpers for platform coherency exit/setup") - arm/firmware.txt was added by commit 7366b92a77fc ("ARM: Add interface for registering and calling firmware-specific operations") - arm/kernel_mode_neon.txt was added by commit 2afd0a05241d ("ARM: 7825/1: document the use of NEON in kernel mode") - arm/tcm.txt was added by commit bc581770cfdd ("ARM: 5580/2: ARM TCM (Tightly-Coupled Memory) support v3") - arm/vlocks.txt was added by commit 9762f12d3e05 ("ARM: mcpm: Add baremetal voting mutexes") - blackfin/gptimers-example.c, Makefile was added by commit 4b60779d5ea7 ("Blackfin: add an example showing how to use the gptimers API") - devicetree/usage-model.txt was added by commit 31134efc681a ("dt: Linux DT usage model documentation") - fb/api.txt was added by commit fb21c2f42879 ("fbdev: Add FOURCC-based format configuration API") - fb/sm501.txt was added by commit e6a049807105 ("video, sm501: add edid and commandline support") - fb/udlfb.txt was added by commit 96f8d864afd6 ("fbdev: move udlfb out of staging.") - filesystems/Makefile was added by commit 1e0051ae48a2 ("Documentation/fs/: split txt and source files") - filesystems/nfs/nfsd-admin-interfaces.txt was added by commit 8a4c6e19cfed ("nfsd: document kernel interfaces for nfsd configuration") - ide/warm-plug-howto.txt was added by commit f74c91413ec6 ("ide: add warm-plug support for IDE devices (take 2)") - laptops/Makefile was added by commit d49129accc21 ("Documentation/laptop/: split txt and source files") - leds/leds-blinkm.txt was added by commit b54cf35a7f65 ("LEDS: add BlinkM RGB LED driver, documentation and update MAINTAINERS") - leds/ledtrig-oneshot.txt was added by commit 5e417281cde2 ("leds: add oneshot trigger") - leds/ledtrig-transient.txt was added by commit 44e1e9f8e705 ("leds: add new transient trigger for one shot timer activation") - m68k/README.buddha was part of the initial repo - networking/LICENSE.(qla3xxx|qlcnic|qlge) was added by commits 40839129f779, c4e84bde1d59, 5a4faa873782 - networking/Makefile was added by commit 3794f3e812ef ("docsrc: build Documentation/ sources") - networking/i40evf.txt was added by commit 105bf2fe6b32 ("i40evf: add driver to kernel build system") - networking/ipsec.txt was added by commit b3c6efbc36e2 ("xfrm: Add file to document IPsec corner case") - networking/mac80211-auth-assoc-deauth.txt was added by commit 3cd7920a2be8 ("mac80211: add auth/assoc/deauth flow diagram") - networking/netlink_mmap.txt was added by commit 5683264c3981 ("netlink: add documentation for memory mapped I/O") - networking/nf_conntrack-sysctl.txt was added by commit c9f9e0e1597f ("netfilter: doc: add nf_conntrack sysctl api documentation") lan) - networking/team.txt was added by commit 3d249d4ca7d0 ("net: introduce ethernet teaming device") - networking/vxlan.txt was added by commit d342894c5d2f ("vxlan: virtual extensible lan") - power/runtime_pm.txt was added by commit 5e928f77a09a ("PM: Introduce core framework for run-time PM of I/O devices (rev. 17)") - power/charger-manager.txt was added by commit 3bb3dbbd56ea ("power_supply: Add initial Charger-Manager driver") - RCU/lockdep-splat.txt was added by commit d7bd2d68aa2e ("rcu: Document interpretation of RCU-lockdep splats") - s390/kvm.txt was added by 5ecee4b (KVM: s390: API documentation) - s390/qeth.txt was added by commit b4d72c08b358 ("qeth: bridgeport support - basic control") - scheduler/sched-bwc.txt was added by commit 88ebc08ea9f7 ("sched: Add documentation for bandwidth control") - scsi/advansys.txt was added by commit 4bd6d7f35661 ("[SCSI] advansys: Move documentation to Documentation/scsi") - scsi/bfa.txt was added by commit 1ec90174bdb4 ("[SCSI] bfa: add readme file") - scsi/bnx2fc.txt was added by commit 12b8fc10eaf4 ("[SCSI] bnx2fc: Add driver documentation") - scsi/cxgb3i.txt was added by commit c3673464ebc0 ("[SCSI] cxgb3i: Add cxgb3i iSCSI driver.") - scsi/hpsa.txt was added by commit 992ebcf14f3c ("[SCSI] hpsa: Add hpsa.txt to Documentation/scsi") - scsi/link_power_management_policy.txt was added by commit ca77329fb713 ("[libata] Link power management infrastructure") - scsi/osd.txt was added by commit 78e0c621deca ("[SCSI] osd: Documentation for OSD library") - scsi/scsi-parameter.txt was created/moved by commit 163475fb111c ("Documentation: move SCSI parameters to their own text file") - serial/driver was part of the initial repo - serial/n_gsm.txt was added by commit 323e84122ec6 ("n_gsm: add a documentation") - timers/Makefile was added by commit 3794f3e812ef ("docsrc: build Documentation/ sources") - virt/kvm/s390.txt was added by commit d9101fca3d57 ("KVM: s390: diagnose call documentation") - vm/split_page_table_lock was added by commit 49076ec2ccaf ("mm: dynamically allocate page->ptl if it cannot be embedded to struct page") - w1/slaves/w1_ds28e04 was added by commit fbf7f7b4e2ae ("w1: Add 1-wire slave device driver for DS28E04-100") - w1/masters/omap-hdq was added by commit e0a29382c6f5 ("hdq: documentation for OMAP HDQ") - x86/early-microcode.txt was added by commit 0d91ea86a895 ("x86, doc: Documentation for early microcode loading") - x86/earlyprintk.txt was added by commit a1aade478862 ("x86/doc: mini-howto for using earlyprintk=dbgp") - x86/entry_64.txt was added by commit 8b4777a4b50c ("x86-64: Document some of entry_64.S") - x86/pat.txt was added by commit d27554d874c7 ("x86: PAT documentation") Moved files - arm/kernel_user_helpers.txt was moved out of arch/arm/kernel by commit 37b8304642c7 ("ARM: kuser: move interface documentation out of the source code") - efi-stub.txt was moved out of x86/ and down into Documentation/ in commit 4172fe2f8a47 ("EFI stub documentation updates") - laptops/hpfall.c was moved out of hwmon/ and into laptops/ in commit efcfed9bad88 ("Move hp_accel to drivers/platform/x86") - commit 5616c23ad9cd ("x86: doc: move x86-generic documentation from Doc/x86/i386"): * x86/usb-legacy-support.txt * x86/boot.txt * x86/zero_page.txt - power/video_extension.txt was moved to acpi in commit 70e66e4df191 ("ACPI / video: move video_extension.txt to Documentation/acpi") Removed files (left in 00-INDEX) - memory.txt was removed by commit 00ea8990aadf ("memory.txt: remove stray information") - gpio.txt was moved to gpio/ in commit fd8e198cfcaa ("Documentation: gpiolib: document new interface") - networking/DLINK.txt was removed by commit 168e06ae26dd ("drivers/net: delete old parallel port de600/de620 drivers") - serial/hayes-esp.txt was removed by commit f53a2ade0bb9 ("tty: esp: remove broken driver") - s390/TAPE was removed by commit 9e280f669308 ("[S390] remove tape block docu") - vm/locking was removed by commit 57ea8171d2bc ("mm: documentation: remove hopelessly out-of-date locking doc") - laptops/acer-wmi.txt was remvoed by commit 020036678e81 ("acer-wmi: Delete out-of-date documentation") Typos/misc issues - rpc-server-gss.txt was added as knfsd-rpcgss.txt in commit 030d794bf498 ("SUNRPC: Use gssproxy upcall for server RPCGSS authentication.") - commit b88cf73d9278 ("net: add missing entries to Documentation/networking/00-INDEX") * generic-hdlc.txt was added as generic_hdlc.txt * spider_net.txt was added as spider-net.txt - w1/master/mxc-w1 was added as mxc_w1 by commit a5fd9139f74c ("w1: add 1-wire master driver for i.MX27 / i.MX31") - s390/zfcpdump.txt was added as zfcpdump by commit 6920c12a407e ("[S390] Add Documentation/s390/00-INDEX.") Signed-off-by: Henrik Austad <henrik@austad.us> Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> [rcu bits] Acked-by: Rob Landley <rob@landley.net> Cc: Jiri Kosina <jkosina@suse.cz> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Rob Herring <robh+dt@kernel.org> Cc: David S. Miller <davem@davemloft.net> Cc: Mark Brown <broonie@kernel.org> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Gleb Natapov <gleb@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Len Brown <len.brown@intel.com> Cc: James Bottomley <JBottomley@parallels.com> Cc: Jean-Christophe Plagniol-Villard <plagnioj@jcrosoft.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-28sched/deadline: Add sched_dl documentationDario Faggioli
Add in Documentation/scheduler/ some hints about the design choices, the usage and the future possible developments of the sched_dl scheduling class and of the SCHED_DEADLINE policy. Reviewed-by: Henrik Austad <henrik@austad.us> Signed-off-by: Dario Faggioli <raistlin@linux.it> Signed-off-by: Juri Lelli <juri.lelli@gmail.com> [ Re-wrote sections 2 and 3. ] Signed-off-by: Luca Abeni <luca.abeni@unitn.it> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/1390821615-23247-1-git-send-email-juri.lelli@gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-11-12Merge tag 'h8300-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging Pull h8300 platform removal from Guenter Roeck: "The patch series has been in -next for more than one relase cycle. I did get a number of Acks, and no objections. H8/300 has been dead for several years, the kernel for it has not compiled for ages, and recent versions of gcc for it are broken. Remove support for it" * tag 'h8300-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging: CREDITS: Add Yoshinori Sato for h8300 fs/minix: Drop dependency on H8300 Drop remaining references to H8/300 architecture Drop MAINTAINERS entry for H8/300 watchdog: Drop references to H8300 architecture net/ethernet: Drop H8/300 Ethernet driver net/ethernet: smsc9194: Drop conditional code for H8/300 ide: Drop H8/300 driver Drop support for Renesas H8/300 (h8300) architecture
2013-09-16Drop support for Renesas H8/300 (h8300) architectureGuenter Roeck
H8/300 has been dead for several years, and the kernel for it has not compiled for ages. Drop support for it. Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Guenter Roeck <linux@roeck-us.net>
2013-09-12sched/Documentation: Update sched-design-CFS.txt documentationLi Bin
2bd2d6f2dc ("sched: Replace use of entity_key()") had remove the entity_key() which function is to subtract a tasks vruntime by its groups minvruntime as the rbtree key. The phrase "there is a subtraction using rq->cfs.min_vruntime to account for possible wraparounds" in documentation feels strange and meaningless. So remove it. Signed-off-by: Li Bin <huawei.libin@huawei.com> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/1378706740-7500-1-git-send-email-huawei.libin@huawei.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-06-19sched: Rename sched.c as sched/core.c in comments and DocumentationViresh Kumar
Most of the stuff from kernel/sched.c was moved to kernel/sched/core.c long time back and the comments/Documentation never got updated. I figured it out when I was going through sched-domains.txt and so thought of fixing it globally. I haven't crossed check if the stuff that is referenced in sched/core.c by all these files is still present and hasn't changed as that wasn't the motive behind this patch. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/cdff76a265326ab8d71922a1db5be599f20aad45.1370329560.git.viresh.kumar@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-09-13sched: Remove __ARCH_WANT_INTERRUPTS_ON_CTXSWPeter Zijlstra
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 <a.p.zijlstra@chello.nl> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Link: http://lkml.kernel.org/n/tip-g9p2a1w81xxbrze25v9zpzbf@git.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-05-17sched: Remove stale power aware scheduling remnants and dysfunctional knobsPeter Zijlstra
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 <a.p.zijlstra@chello.nl> Cc: Suresh Siddha <suresh.b.siddha@intel.com> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Vincent Guittot <vincent.guittot@linaro.org> Cc: Vaidyanathan Srinivasan <svaidy@linux.vnet.ibm.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> Link: http://lkml.kernel.org/r/1326104915.2442.53.camel@twins Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-05-07sched: Update documentation and commentsHiroshi Shimamoto
Change sched_*.c to sched/*.c in documentation and comments. Signed-off-by: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/4F795CAC.9080206@ct.jp.nec.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-01-27sched: Remove sched_switchRakib Mullick
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 <rakib.mullick@gmail.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1327422836.27181.5.camel@localhost.localdomain Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-08-14sched: Add documentation for bandwidth controlBharata B Rao
Basic description of usage and effect for CFS Bandwidth Control. Signed-off-by: Bharata B Rao <bharata@linux.vnet.ibm.com> Signed-off-by: Paul Turner <pjt@google.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/20110721184758.498036116@google.com Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-07-11Merge branch 'master' into for-nextJiri Kosina
Sync with Linus' tree to be able to apply pending patches that are based on newer code already present upstream.
2011-06-15Documentation: update cgroupfs mount pointJörg Sommer
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 <joerg@alea.gnuu.de> Acked-by: Paul Menage <menage@google.com> Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-06-13doc: fix wrong arch/i386 referencesWanlong Gao
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 <wanlong.gao@gmail.com> [jkosina@suse.cz: reword changelog] Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2011-03-31sched, doc: Beef up load balancing descriptionBorislav Petkov
Correct all function names pertaining to load balancing and explain shortly how load balancing is performed. Signed-off-by: Borislav Petkov <bp@alien8.de> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> LKML-Reference: <1301241433-3790-1-git-send-email-bp@alien8.de> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-03-23sched, doc: Update sched-design-CFS.txtBorislav Petkov
Correct ->dequeue_tree() thinko into sched_class->dequeue_task and drop all references to ->task_new() since it is obviously gone. Signed-off-by: Borislav Petkov <borislav.petkov@amd.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Mike Galbraith <efault@gmx.de> LKML-Reference: <1300815978-16618-1-git-send-email-bp@amd64.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-02-01sched, docs: Update schedstats documentation to version 15Javi Merino
Version 15 of schedstats was introduced in: 67aa0f767af4: sched: remove unused fields from struct rq and removed three unused counters in sched_yield(). Update the documentation. Signed-off-by: Javi Merino <cibervicho@gmail.com> Cc: henrix@sapo.pt Cc: rdunlap@xenotime.net Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Mike Galbraith <efault@gmx.de> LKML-Reference: <1296515496-8229-1-git-send-email-cibervicho@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>