On Sun, Aug 23, 2015 at 10:29:15PM -0700, Paul E. McKenney wrote: > On Sun, Aug 23, 2015 at 10:07:49PM -0700, David Miller wrote: > > > > 1) Doc bug, documentation mentions torture_type such as "rcu_sync", > > but those don't seem to exist. > > > > 2) If you specify an unrecognized type, the module cannot be unloaded. > > Amusingly it says that it cannot unload because the unrecognized > > torture test type you requested is "running" :-) > > Clearly Iftekhar was mutating the wrong code. ;-) > > And clearly I need to occasionally test failure cases. There is code that > is supposed to unwind upon failure, but it has apparently bitrotted...
Do the following pair of untested patches help? Thanx, Paul ------------------------------------------------------------------------ commit d568705d102ceb61884a3a8b77a98168094acbca Author: Paul E. McKenney <paul...@linux.vnet.ibm.com> Date: Mon Aug 24 11:37:58 2015 -0700 rcutorture: Fix module unwind when bad torture_type specified The rcutorture 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. Reported-by: David Miller <da...@davemloft.net> Signed-off-by: Paul E. McKenney <paul...@linux.vnet.ibm.com> diff --git a/kernel/rcu/rcutorture.c b/kernel/rcu/rcutorture.c index f9ec6cbe77d3..9c4f5cd86532 100644 --- a/kernel/rcu/rcutorture.c +++ b/kernel/rcu/rcutorture.c @@ -695,7 +695,7 @@ static bool __maybe_unused torturing_tasks(void) #define RCUTORTURE_TASKS_OPS -static bool torturing_tasks(void) +static bool __maybe_unused torturing_tasks(void) { return false; } @@ -1742,8 +1742,8 @@ rcu_torture_init(void) for (i = 0; i < ARRAY_SIZE(torture_ops); i++) pr_alert(" %s", torture_ops[i]->name); pr_alert("\n"); - torture_init_end(); - return -EINVAL; + firsterr = -EINVAL; + goto unwind; } if (cur_ops->fqs == NULL && fqs_duration != 0) { pr_alert("rcu-torture: ->fqs NULL and non-zero fqs_duration, fqs disabled.\n"); ------------------------------------------------------------------------ commit 20f34145cfbba04b44b8fbd29689bdcc0ab0b303 Author: Paul E. McKenney <paul...@linux.vnet.ibm.com> Date: Mon Aug 24 11:46:00 2015 -0700 documentation: Catch up list of torture_type options This commit rids the documentation of long-obsolete torture_type options such as rcu_sync and adds new ones such as tasks. Also add verbiage noting the fact that rcutorture now concurrently tests the asynchrounous, synchronous, expedited synchronous, and polling grace-period primitives. Reported-by: David Miller <da...@davemloft.net> Signed-off-by: Paul E. McKenney <paul...@linux.vnet.ibm.com> diff --git a/Documentation/RCU/torture.txt b/Documentation/RCU/torture.txt index dac02a6219b1..118e7c176ce7 100644 --- a/Documentation/RCU/torture.txt +++ b/Documentation/RCU/torture.txt @@ -166,40 +166,27 @@ test_no_idle_hz Whether or not to test the ability of RCU to operate in torture_type The type of RCU to test, with string values as follows: - "rcu": rcu_read_lock(), rcu_read_unlock() and call_rcu(). - - "rcu_sync": rcu_read_lock(), rcu_read_unlock(), and - synchronize_rcu(). - - "rcu_expedited": rcu_read_lock(), rcu_read_unlock(), and - synchronize_rcu_expedited(). + "rcu": rcu_read_lock(), rcu_read_unlock() and call_rcu(), + along with expedited, synchronous, and polling + variants. "rcu_bh": rcu_read_lock_bh(), rcu_read_unlock_bh(), and - call_rcu_bh(). - - "rcu_bh_sync": rcu_read_lock_bh(), rcu_read_unlock_bh(), - and synchronize_rcu_bh(). + call_rcu_bh(), along with expedited and synchronous + variants. - "rcu_bh_expedited": rcu_read_lock_bh(), rcu_read_unlock_bh(), - and synchronize_rcu_bh_expedited(). + "rcu_busted": This tests an intentionally incorrect version + of RCU in order to help test rcutorture itself. "srcu": srcu_read_lock(), srcu_read_unlock() and - call_srcu(). - - "srcu_sync": srcu_read_lock(), srcu_read_unlock() and - synchronize_srcu(). - - "srcu_expedited": srcu_read_lock(), srcu_read_unlock() and - synchronize_srcu_expedited(). + call_srcu(), along with expedited and + synchronous variants. "sched": preempt_disable(), preempt_enable(), and - call_rcu_sched(). - - "sched_sync": preempt_disable(), preempt_enable(), and - synchronize_sched(). + call_rcu_sched(), along with expedited, + synchronous, and polling variants. - "sched_expedited": preempt_disable(), preempt_enable(), and - synchronize_sched_expedited(). + "tasks": voluntary context switch and call_rcu_tasks(), + along with expedited and synchronous variants. Defaults to "rcu". -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/