rcutorture changes for 3.20

Hello!

This series contains rcutorture updates for 3.20:

1. Issue warnings on close calls due to Reader Batch blows.
This diagnostic would have spotted the ugly preemptible-RCU CPU-hotplug bug some years back.

2. Make _batches_completed() functions return unsigned long to
avoid signed overflow issues.

3. Make build-output parsing correctly flag RCU's warnings.
These needed to be updated when the "rcu" directory was created in "kernel."

4. Use unsigned long for Reader Batch computations, avoiding
signed overflow.

5. Provide rcu_batches_completed_sched() for TINY_RCU for new
rcutorture compatibility.

6. Drop rcu_torture_completed() and friends. Now that the types
match, the wrappers aren't needed.

7. Remove redundant rcu_batches_completed() declaration.

8. Check from beginning to end of grace period instead of from
end of previous grace period to end of next one. This makes rcutorture more sensitive to RCU bugs that make the grace period too short.

9. Handle different mpstat versions -- new versions added fields.

10. torture: Add "-enable-kvm -soundhw pcspk" to qemu command line,
as newer versions of qemu complain if they are missing.

11. Flag console.log file to prevent holdovers from earlier runs,
which could make a run look successful when it didn't even get to the point of starting qemu.

12. Add more diagnostics in rcu_barrier() test failure case.

Thanx, Paul

------------------------------------------------------------------------

 b/include/linux/rcutiny.h                                   |   42 ++++++
 b/include/linux/rcutree.h                                   |    9 -
 b/kernel/rcu/rcutorture.c                                   |   74 ++++++------
 b/kernel/rcu/tree.c                                         |   44 ++++++-
 b/kernel/rcu/tree.h                                         |    3 
 b/kernel/rcu/tree_plugin.h                                  |   34 -----
 b/tools/testing/selftests/rcutorture/bin/cpus2use.sh        |    2 
 b/tools/testing/selftests/rcutorture/bin/kvm-recheck-rcu.sh |   18 ++
 b/tools/testing/selftests/rcutorture/bin/kvm-test-1-run.sh  |    9 -
 b/tools/testing/selftests/rcutorture/bin/parse-build.sh     |   20 ++-
 10 files changed, 166 insertions(+), 89 deletions(-)