Pull RCU updates from Ingo Molnar:
"Main changes:
- Torture-test changes, including refactoring of rcutorture and
introduction of a vestigial locktorture.
- Real-time latency fixes.
- Documentation updates.
- Miscellaneous fixes"
* 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (77 commits)
rcu: Provide grace-period piggybacking API
rcu: Ensure kernel/rcu/rcu.h can be sourced/used stand-alone
rcu: Fix sparse warning for rcu_expedited from kernel/ksysfs.c
notifier: Substitute rcu_access_pointer() for rcu_dereference_raw()
Documentation/memory-barriers.txt: Clarify release/acquire ordering
rcutorture: Save kvm.sh output to log
rcutorture: Add a lock_busted to test the test
rcutorture: Place kvm-test-1-run.sh output into res directory
rcutorture: Rename TREE_RCU-Kconfig.txt
locktorture: Add kvm-recheck.sh plug-in for locktorture
rcutorture: Gracefully handle NULL cleanup hooks
locktorture: Add vestigial locktorture configuration
rcutorture: Introduce "rcu" directory level underneath configs
rcutorture: Rename kvm-test-1-rcu.sh
rcutorture: Remove RCU dependencies from ver_functions.sh API
rcutorture: Create CFcommon file for common Kconfig parameters
rcutorture: Create config files for scripted test-the-test testing
rcutorture: Add an rcu_busted to test the test
locktorture: Add a lock-torture kernel module
rcutorture: Abstract kvm-recheck.sh
...
This commit logs the progress text that kvm.sh outputs, improving
after-the-fact troubleshooting.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
The output of each kvm-test-1-run.sh script is placed into a file
whose name parallels that of the build directory. This means that
the kvm-test-1-run.sh output is overwritten by later run. This
commit therefore places the kvm-test-1-run.sh output into the
per-test-case directory in the "res" hierarchy.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
It used to be that:
git ls-files "*Kconfig*"
would find all Kconfig files and would only find Kconfig files. This
commit renames TREE_RCU-Kconfig.txt to TREE_RCU-kconfig.txt so that this
is once again true.
Signed-off-by: Paul Bolle <pebolle@tiscali.nl>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
This commit adds the kvm-recheck-lock.sh plug-in for locktorture to
print out lock-specific progress statistics.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
This commit uses the standard software ploy of introducing another
level of indirection below the configs directory. This allows each
torture-test suite to have its own set of Kconfig files, boot parameters,
and version-specific scripts. Initially, we have only rcu, but lock
will follow soonish.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
The kvm-test-1-rcu.sh is not specific to RCU, so this commit renames it
to kvm-test-1-run.sh.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
The current set of functions in ver_functions.sh have APIs that are
specific to RCU. This commit therefore makes an RCU-independent function
that outputs version-specific boot arguments. This has the benefit that
a test-type-independent call in kvm-test-1-rcu.sh can now handle any type
of test, given a test-type-specific set of files in a configs directory.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Currently, CONFIG_RCU_TORTURE_TEST=y is hardcoded into the
kvm-test-1-rcu.sh script and CONFIG_PRINTK_TIME=y is mentioned in each
and every configs file. This commit creates a CFcommon file for these
two Kconfig parameters, and modifies kvm-test-1-rcu.sh to copy this new
file into the .config file during the build. This change will allow
these scripts to operate on torture types other than just rcutorture.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
This commit adds a pair of files in the configs directory to allow
test-the-test runs of rcutorture via a "--configs BUSTED" argument to
the kvm.sh script.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
This commit creates a plug-in to allow kvm-recheck.sh to process
non-rcutorture console output.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
This commit prevents the results directory from being created for
dryruns. However, a script generated from a dryrun will create
the results directory should it be run.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org
This commit adds a "(!)" flag after the number of CPUs required by a
given test if that test requires more than the available number of CPUs.
Note that these flags appear only when the number of CPUs is specified
using the --cpus argument. In the absence of a --cpus argument, no
tests are flagged.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Running the standard set of rcutorture tests on 24 CPUs results in
the following sub-optimal schedule:
----start batch----
TREE07 16
----start batch----
TREE08 16
SRCU-P 8
----start batch----
TREE01 8
TREE02 8
TREE03 8
----start batch----
TREE04 8
TREE05 8
TREE06 8
----start batch----
SRCU-N 4
TINY01 1
TINY02 1
TREE09 1
If one of the eight-CPU runs were to be moved into the first batch,
the test suite would complete in four batches rather than five.
This commit therefore uses a greedy algorithm to re-order the test
entries so that the sequential batching will produce an optimal schedule
in this case:
----start batch----
TREE07 16
SRCU-P 8
----start batch----
TREE08 16
TREE01 8
----start batch----
TREE02 8
TREE03 8
TREE04 8
----start batch----
TREE05 8
TREE06 8
SRCU-N 4
TINY01 1
TINY02 1
TREE09 1
Please note that this is still not an optimal bin-packing algorithm,
however, it does produce optimal solutions for most common scenarios.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
This commit fixes handling numbering of multiple runs of the same test
so as to disambiguate output.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Actual rcutorture tests take considerable time and machine resources,
so it is inconvenient to actually do an rcutorture run when optimizing
the bin-packing algorithm. This commit therefore adds a --dryrun
argument, which defaults to doing a run, but for which "sched"
says to simply print the run schedule and "script" dumps the script
without running it.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
The message complains about a build directory when it should instead
be complaining about the results directory, so this commit fixes it.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
The rcutorture tests run by default range from using one CPU to using
sixteen of them. Therefore, rcutorture testing could be sped up
significantly simply by running the kernels in parallel. Building
them in parallel is not all that helpful: "make -j" is usually a
better bet. So this commit takes a new "--cpus" argument that
specifies how many CPUs rcutorture is permitted to use for its
parallel runs. The default of zero does sequential runs as before.
The bin-packing is minimal, and will be grossly suboptimal for
some configurations. However, powers of two work reasonably well.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Both SRCU-P and SRCU-N specify eight CPUs, which results in four
iterations for a parallel run on 32 CPUs. This commit reduces SRCU-N
to four CPUs (but leaving SRCU-P at eight) to speed up parallel runs,
while maintaining essentially the same test coverage.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Currently, most qemu flags are calculated in kvm-test-1-rcu.sh,
except that -nographics is set up by kvm.sh. This commit promotes
one-stop shopping by consolidating the determination of qemu flags into
kvm-test-1-rcu.sh.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>