user/sven/linux.git/Documentation/locking, branch v4.16.1

Documentation/locking/mutex-design: Update to reflect latest changes

2018-02-11T11:28:58Z

Commit 3ca0ff571b09 ("locking/mutex: Rework mutex::owner") reworked the basic mutex implementation to deal with several problems. Documentation was however left unchanged and became stale. Update mutex-design.txt to reflect changes introduced by the above commit. Signed-off-by: Juri Lelli Cc: Andrew Morton Cc: Davidlohr Bueso Cc: Jonathan Corbet Cc: Linus Torvalds Cc: Paul E. McKenney Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: linux-doc@vger.kernel.org Link: http://lkml.kernel.org/r/20180209160114.19980-1-juri.lelli@redhat.com [ Small readability tweaks to the text. ] Signed-off-by: Ingo Molnar

Merge branch 'for-mingo' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into core/rcu

2018-01-03T13:14:18Z

Pull RCU updates from Paul E. McKenney: - Updates to use cond_resched() instead of cond_resched_rcu_qs() where feasible (currently everywhere except in kernel/rcu and in kernel/torture.c). Also a couple of fixes to avoid sending IPIs to offline CPUs. - Updates to simplify RCU's dyntick-idle handling. - Updates to remove almost all uses of smp_read_barrier_depends() and read_barrier_depends(). - Miscellaneous fixes. - Torture-test updates. Signed-off-by: Ingo Molnar

locking/lockdep: Remove the cross-release locking checks

2017-12-12T11:38:51Z

This code (CONFIG_LOCKDEP_CROSSRELEASE=y and CONFIG_LOCKDEP_COMPLETIONS=y), while it found a number of old bugs initially, was also causing too many false positives that caused people to disable lockdep - which is arguably a worse overall outcome. If we disable cross-release by default but keep the code upstream then in practice the most likely outcome is that we'll allow the situation to degrade gradually, by allowing entropy to introduce more and more false positives, until it overwhelms maintenance capacity. Another bad side effect was that people were trying to work around the false positives by uglifying/complicating unrelated code. There's a marked difference between annotating locking operations and uglifying good code just due to bad lock debugging code ... This gradual decrease in quality happened to a number of debugging facilities in the kernel, and lockdep is pretty complex already, so we cannot risk this outcome. Either cross-release checking can be done right with no false positives, or it should not be included in the upstream kernel. ( Note that it might make sense to maintain it out of tree and go through the false positives every now and then and see whether new bugs were introduced. ) Cc: Byungchul Park Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar

torture: Eliminate torture_runnable and perf_runnable

2017-12-11T17:18:29Z

The purpose of torture_runnable is to allow rcutorture and locktorture to be started and stopped via sysfs when they are built into the kernel (as in not compiled as loadable modules). However, the 0444 permissions for both instances of torture_runnable prevent this use case from ever being put into practice. Given that there have been no complaints about this deficiency, it is reasonable to conclude that no one actually makes use of this sysfs capability. The perf_runnable module parameter for rcuperf is in the same situation. This commit therefore removes both torture_runnable instances as well as perf_runnable. Reported-by: Thomas Gleixner Signed-off-by: Paul E. McKenney

Documentation: fix locking rt-mutex doc refs

2017-10-19T18:56:44Z

Signed-off-by: Tom Saeger Signed-off-by: Jonathan Corbet

Merge branch 'linus' into locking/core, to fix up conflicts

2017-09-04T09:01:18Z

Conflicts: mm/page_alloc.c Signed-off-by: Ingo Molnar

rtmutex: update rt-mutex

2017-08-24T19:38:14Z

The rtmutex remove a pending owner bit in in rt_mutex::owner, in commit 8161239a8bcc ("rtmutex: Simplify PI algorithm and make highest prio task get lock") But the document was changed accordingly. Updating it to a meaningful state. BTW, as 'Steven Rostedt' mentioned: There is still technically a "Pending Owner", it's just not called that anymore. The pending owner happens to be the top_waiter of a lock that has no owner and has been woken up to grab the lock. Signed-off-by: Alex Shi Cc: Steven Rostedt Cc: Sebastian Siewior Cc: Mathieu Poirier Cc: Juri Lelli Cc: Thomas Gleixner To: linux-doc@vger.kernel.org To: linux-kernel@vger.kernel.org To: Jonathan Corbet To: Ingo Molnar To: Peter Zijlstra Signed-off-by: Jonathan Corbet

rtmutex: update rt-mutex-design

2017-08-24T19:37:55Z

The rt-mutex-design documents didn't gotten meaningful update from its first version. Even after owner's pending bit was removed in commit 8161239a8bcc ("rtmutex: Simplify PI algorithm and make highest prio task get lock") and priority list 'plist' changed to rbtree. And Peter Zijlstra did some clean up and fix for deadline task changes on tip tree. So update it to latest code and make it meaningful. Steven Rostedt and Sebastian Siewior gave much of comments and input in this doc. Thanks! Signed-off-by: Alex Shi Cc: Steven Rostedt Cc: Sebastian Siewior Cc: Mathieu Poirier Cc: Juri Lelli Cc: Thomas Gleixner To: linux-doc@vger.kernel.org To: linux-kernel@vger.kernel.org To: Jonathan Corbet To: Ingo Molnar To: Peter Zijlstra Signed-off-by: Jonathan Corbet

locking/lockdep: Add 'crossrelease' feature documentation

2017-08-10T10:32:37Z

This document describes the concept of crossrelease feature. Signed-off-by: Byungchul Park Signed-off-by: Peter Zijlstra (Intel) Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: akpm@linux-foundation.org Cc: boqun.feng@gmail.com Cc: kernel-team@lge.com Cc: kirill@shutemov.name Cc: npiggin@gmail.com Cc: walken@google.com Cc: willy@infradead.org Link: http://lkml.kernel.org/r/1502089981-21272-15-git-send-email-byungchul.park@lge.com Signed-off-by: Ingo Molnar

locking/ww_mutex/Documentation: Update the design document

2017-01-14T10:14:55Z

Document the invariants we maintain for the wait list of ww_mutexes. Signed-off-by: Nicolai Hähnle Signed-off-by: Peter Zijlstra (Intel) Cc: Andrew Morton Cc: Chris Wilson Cc: Daniel Vetter Cc: Linus Torvalds Cc: Maarten Lankhorst Cc: Paul E. McKenney Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: dri-devel@lists.freedesktop.org Link: http://lkml.kernel.org/r/1482346000-9927-13-git-send-email-nhaehnle@gmail.com Signed-off-by: Ingo Molnar