BMC/Intel-BMC/linux.git/tools/testing/selftests/rcutorture/configs, branch dev

Merge branches 'array.2015.05.27a', 'doc.2015.05.27a', 'fixes.2015.05.27a', 'hotplug.2015.05.27a', 'init.2015.05.27a', 'tiny.2015.05.27a' and 'torture.2015.05.27a' into HEAD

2015-05-27T20:00:49+00:00

array.2015.05.27a: Remove all uses of RCU-protected array indexes. doc.2015.05.27a: Docuemntation updates. fixes.2015.05.27a: Miscellaneous fixes. hotplug.2015.05.27a: CPU-hotplug updates. init.2015.05.27a: Initialization/Kconfig updates. tiny.2015.05.27a: Updates to Tiny RCU. torture.2015.05.27a: Torture-testing updates.

rcutorture: Update TREE_RCU-kconfig.txt

2015-05-27T20:00:00+00:00

This commit updates TREE_RCU-kconfig.txt to reflect changes in RCU's Kconfig setup. This commit also updates rcutorture's Kconfig fragments to account for Kconfig parameters that are now driven directly off of other Kconfig parameters. The #CHECK# prefix tells the rcutorture scripts to take no action to try to set the Kconfig parameter, but to check that it does in fact get set. This is useful for verifying that Kconfig parameters that are supposed to be automatically set do in fact get set to the required values. Reported-by: Pranith Kumar Signed-off-by: Paul E. McKenney Reviewed-by: Josh Triplett

rcutorture: Make rcutorture scripts force RCU_EXPERT

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

This commit causes the rcutorture scripts to force RCU_EXPERT so that these scripts can cause rcutorture to torture RCU in the various required configurations. However, SRCU-P, TASKS03, and TREE09 retain !RCU_EXPERT in order to ensure testing of the vanilla configuration. Signed-off-by: Paul E. McKenney Reviewed-by: Pranith Kumar Reviewed-by: Josh Triplett

rcutorture: Update configuration fragments for rcutree.rcu_fanout_exact

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

This commit updates rcutortures configuration-fragment files to account for the move from the CONFIG_RCU_FANOUT_EXACT Kconfig parameter to the new rcutree.rcu_fanout_exact= boot parameter. Signed-off-by: Paul E. McKenney Reviewed-by: Pranith Kumar Reviewed-by: Josh Triplett

rcutorture: TASKS_RCU set directly, so don't explicitly set it

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

The TASKS01, TASKS02, and TASKS03 rcutorture config fragments currently set CONFIG_TASKS_RCU. However, now that the value of this Kconfig parameter is set via "select" statements, it is no longer necessary to set it explicitly. This commit therefore removes it from the Kconfig fragments. Signed-off-by: Paul E. McKenney Reviewed-by: Pranith Kumar Reviewed-by: Josh Triplett

rcutorture: Test SRCU cleanup code path

2015-05-27T19:59:58+00:00

The current rcutorture testing does not do any cleanup operations. This works because the srcu_struct is statically allocated, but it does represent a memory leak of the associated dynamically allocated ->per_cpu_ref per-CPU variables. However, rcutorture currently uses a statically allocated srcu_struct, which cannot legally be passed to cleanup_srcu_struct(). Therefore, this commit adds a second form of srcu (called srcud) that dynamically allocates and frees the associated per-CPU variables. This commit also adds a ->cleanup() member to rcu_torture_ops that is invoked at the end of the test, after ->cb_barriers(). This ->cleanup() pointer is NULL for all existing tests, and thus only used for scrud. Finally, the SRCU-P torture-test configuration selects scrud instead of srcu, with SRCU-N continuing to use srcu, thereby testing both static and dynamic srcu_struct structures. Reported-by: "Ahmed, Iftekhar" Signed-off-by: Paul E. McKenney Reviewed-by: Josh Triplett

rcutorture: Exchange TREE03 and TREE08 NR_CPUS, speed up CPU hotplug

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

TREE03 has been especially effective at finding bugs lately. This commit makes it even more effective by speeding up its CPU hotplug testing and increasing its NR_CPUs from 8 to 16. TREE08's NR_CPUS is decreased from 16 to 8 in order to maintain the same test duration. Signed-off-by: Paul E. McKenney Reviewed-by: Josh Triplett

rcutorture: Exchange TREE03 and TREE04 geometries

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

Given that the combination of PREEMPT_RCU and HOTPLUG_CPU is producing the most bugs lately, this commit swaps the TREE03 and TREE04 rcu_node-tree geometries so that the test exercising PREEMPT_RCU and HOTPLUG_CPU has three-level rather than two-level rcu_node trees. Signed-off-by: Paul E. McKenney Reviewed-by: Josh Triplett

rcutorture: Test both RCU-sched and RCU-bh for Tiny RCU

2015-05-27T19:59:31+00:00

Tiny RCU supports both RCU-sched and RCU-bh, but only RCU-sched is currently tested by the rcutorture scripts. This commit therefore changes the TINY02 configuration to test RCU-bh, with TINY01 continuing to test RCU-sched. This shortcoming of the current rcutorture tests was located by mutation testing by Iftekhar. The idea behind mutation testing is to automatically mutate the code under test. If a given mutant is not caught by testing, this is a hint that the testing might need to be improved, as was the case here. Note that this is only a hint because it is possible to mutate the code into something else that still works. For example, a mutation that removes (say) a WARN_ON() will not normally result in a test failure. This change resulted in the test failure caused by list mishandling, which is fixed by the next commit. Reported-by: "Ahmed, Iftekhar" Signed-off-by: Paul E. McKenney Reviewed-by: Josh Triplett

rcu: Provide diagnostic option to slow down grace-period scans

2015-05-27T19:59:02+00:00

Grace-period scans of the rcu_node combining tree normally proceed quite quickly, so that it is very difficult to reproduce races against them. This commit therefore allows grace-period pre-initialization and cleanup to be artificially slowed down, increasing race-reproduction probability. A pair of pairs of new Kconfig parameters are provided, RCU_TORTURE_TEST_SLOW_PREINIT to enable the slowing down of propagating CPU-hotplug changes up the combining tree along with RCU_TORTURE_TEST_SLOW_PREINIT_DELAY to specify the delay in jiffies, and RCU_TORTURE_TEST_SLOW_CLEANUP to enable the slowing down of the end-of-grace-period cleanup scan along with RCU_TORTURE_TEST_SLOW_CLEANUP_DELAY to specify the delay in jiffies. Boot-time parameters named rcutree.gp_preinit_delay and rcutree.gp_cleanup_delay allow these delays to be specified at boot time. Signed-off-by: Paul E. McKenney