Hello, On Thu, 2 May 2013, Julian Anastasov wrote: > Note that I'm testing on some 9-year old > UP system, i.e. 1 CPU. Now I enabled SMP to test CONFIG_TREE_RCU > and the results are same. I think, it should be just like > the TINY_RCU in terms of these debuggings (non-preempt). Extra > rcu_read_lock gives me "Illegal context switch in RCU read-side > critical section" in addition to the "BUG: sleeping function > called from invalid context" message. Just to clarify about the test with extra rcu_read_lock because above paragraph is very confusing: - The __might_sleep call with PREEMPT_ACTIVE | PREEMPT_RCU_OFFSET just warns with "BUG: sleeping function called from invalid context" because its rcu_sleep_check is silenced. We match the nesting depth only. - but __cond_resched -> __schedule -> schedule_debug warns about the extra rcu_read_lock() with "BUG: scheduling while atomic" and then with "Illegal context switch in RCU read-side critical section" from rcu_sleep_check(0). Regards -- Julian Anastasov <ja@xxxxxx> -- To unsubscribe from this list: send the line "unsubscribe lvs-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
