linux-toradex.git/kernel/locking/locktorture.c, branch v4.4-rc6

Merge branches 'doc.2015.10.06a', 'percpu-rwsem.2015.10.06a' and 'torture.2015.10.06a' into HEAD

2015-10-07T23:06:25+00:00

doc.2015.10.06a:  Documentation updates.
percpu-rwsem.2015.10.06a:  Optimization of per-CPU reader-writer semaphores.
torture.2015.10.06a:  Torture-test updates.

locktorture: Fix module unwind when bad torture_type specified

2015-10-06T18:28:44+00:00

The locktorture module has a list of torture types, and specifying
a type not on this list is supposed to cleanly fail the module load.
Unfortunately, the "fail" happens without the "cleanly".  This commit
therefore adds the needed clean-up after an incorrect torture_type.

Signed-off-by: Paul E. McKenney 
Reviewed-by: Josh Triplett

locktorture: Add torture tests for percpu_rwsem

2015-10-06T18:24:56+00:00

This commit adds percpu_rwsem tests based on the earlier rwsem tests.

Signed-off-by: Paul E. McKenney 
Cc: Oleg Nesterov 
Cc: Davidlohr Bueso 
Reviewed-by: Josh Triplett

locktorture: Support rtmutex torturing

2015-10-06T18:24:40+00:00

Real time mutexes is one of the few general primitives
that we do not have in locktorture. Address this -- a few
considerations:

o To spice things up, enable competing thread(s) to become
rt, such that we can stress different prio boosting paths
in the rtmutex code. Introduce a ->task_boost callback,
only used by rtmutex-torturer. Tasks will boost/deboost
around every 50k (arbitrarily) lock/unlock operations.

o Hold times are similar to what we have for other locks:
only occasionally having longer hold times (per ~200k ops).
So we roughly do two full rt boost+deboosting ops with
short hold times.

Signed-off-by: Davidlohr Bueso 
Signed-off-by: Paul E. McKenney 
Reviewed-by: Josh Triplett

locktorture: Change longdelay_us to longdelay_ms

2015-05-27T19:59:57+00:00

The locktorture long delays are in milliseconds rather than microseconds,
so this commit changes the name of the corresponding variable from
longdelay_us to longdelay_ms.

Reported-by: Ben Goodwyn 
Signed-off-by: Paul E. McKenney 
Cc: Davidlohr Bueso 
Reviewed-by: Josh Triplett

locktorture: fix deadlock in 'rw_lock_irq' type

2015-05-27T19:59:56+00:00

torture_rwlock_read_unlock_irq() must use read_unlock_irqrestore()
instead of write_unlock_irqrestore().

Use read_unlock_irqrestore() instead of write_unlock_irqrestore().

Signed-off-by: Alexey Kodanev 
Signed-off-by: Paul E. McKenney 
Reviewed-by: Josh Triplett

locktorture: Cleanup header usage

2014-09-30T07:10:02+00:00

Remove some unnecessary ones and explicitly include rwsem.h

Signed-off-by: Davidlohr Bueso 
Signed-off-by: Paul E. McKenney

locktorture: Cannot hold read and write lock

2014-09-30T07:10:02+00:00

... trigger an error if so.

Signed-off-by: Davidlohr Bueso 
Signed-off-by: Paul E. McKenney

locktorture: Fix __acquire annotation for spinlock irq

2014-09-30T07:10:02+00:00

Its quite easy to get mixed up with the names -- 'torture_spinlock_irq'
is not actually a valid spinlock name.

Signed-off-by: Davidlohr Bueso 
Signed-off-by: Paul E. McKenney

locktorture: Support rwlocks

2014-09-30T07:10:00+00:00

Add a "rw_lock" torture test to stress kernel rwlocks and their irq
variant. Reader critical regions are 5x longer than writers. As such
a similar ratio of lock acquisitions is seen in the statistics. In the
case of massive contention, both hold the lock for 1/10 of a second.

Signed-off-by: Davidlohr Bueso 
Signed-off-by: Paul E. McKenney