Commit Graph

7 Commits

Author SHA1 Message Date
Boqun Feng
857811a371 locking/ww_mutex: Adjust the lock number for stress test
Because there are only 12 bits in held_lock::references, so we only
support 4095 nested lock held in the same time, adjust the lock number
for ww_mutex stress test to kill one lockdep splat:

  [ ] [ BUG: bad unlock balance detected! ]
  [ ] kworker/u2:0/5 is trying to release lock (ww_class_mutex) at:
  [ ] ww_mutex_unlock()
  [ ] but there are no more locks to release!
  ...

Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Fengguang Wu <fengguang.wu@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Nicolai Hähnle <Nicolai.Haehnle@amd.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20170301150138.hdixnmafzfsox7nn@tardis.cn.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-02 09:00:39 +01:00
Chris Wilson
2b232e0c3b locking/ww_mutex: Replace cpu_relax() with cond_resched() for tests
When busy-spinning on a ww_mutex_trylock(), we depend upon the other
thread advancing and releasing the lock. This can not happen on a single
CPU unless we relinquish it:

  [ ] NMI watchdog: BUG: soft lockup - CPU#0 stuck for 22s! [kworker/0:1:18]
  ...
  [ ] Call Trace:
  [ ]  mutex_trylock()
  [ ]  test_mutex_work+0x31/0x56
  [ ]  process_one_work+0x1b4/0x2f9
  [ ]  worker_thread+0x1b0/0x27c
  [ ]  kthread+0xd1/0xd3
  [ ]  ret_from_fork+0x19/0x30

Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: f2a5fec173 ("locking/ww_mutex: Begin kselftests for ww_mutex")
Link: http://lkml.kernel.org/r/20170228094011.2595-1-chris@chris-wilson.co.uk
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-02 09:00:38 +01:00
Chris Wilson
2a0c112828 locking/ww_mutex: Add kselftests for ww_mutex stress
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Maarten Lankhorst <dev@mblankhorst.nl>
Cc: Nicolai Hähnle <nhaehnle@gmail.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20161201114711.28697-8-chris@chris-wilson.co.uk
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-01-14 11:37:17 +01:00
Chris Wilson
d1b42b800e locking/ww_mutex: Add kselftests for resolving ww_mutex cyclic deadlocks
Check that ww_mutexes can detect cyclic deadlocks (generalised ABBA
cycles) and resolve them by lock reordering.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Maarten Lankhorst <dev@mblankhorst.nl>
Cc: Nicolai Hähnle <nhaehnle@gmail.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20161201114711.28697-7-chris@chris-wilson.co.uk
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-01-14 11:37:16 +01:00
Chris Wilson
70207686e4 locking/ww_mutex: Add kselftests for ww_mutex ABBA deadlock detection
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Maarten Lankhorst <dev@mblankhorst.nl>
Cc: Nicolai Hähnle <nhaehnle@gmail.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20161201114711.28697-6-chris@chris-wilson.co.uk
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-01-14 11:37:16 +01:00
Chris Wilson
c22fb3807f locking/ww_mutex: Add kselftests for ww_mutex AA deadlock detection
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Maarten Lankhorst <dev@mblankhorst.nl>
Cc: Nicolai Hähnle <nhaehnle@gmail.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20161201114711.28697-5-chris@chris-wilson.co.uk
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-01-14 11:37:15 +01:00
Chris Wilson
f2a5fec173 locking/ww_mutex: Begin kselftests for ww_mutex
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Maarten Lankhorst <dev@mblankhorst.nl>
Cc: Nicolai Hähnle <nhaehnle@gmail.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20161201114711.28697-4-chris@chris-wilson.co.uk
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-01-14 11:37:14 +01:00