1This document gives a brief rationale for the TREE_RCU-related test 2cases, a group that includes PREEMPT_RCU. 3 4 5Kconfig Parameters: 6 7CONFIG_DEBUG_LOCK_ALLOC -- Do three, covering CONFIG_PROVE_LOCKING & not. 8CONFIG_DEBUG_OBJECTS_RCU_HEAD -- Do one. 9CONFIG_HZ_PERIODIC -- Do one. 10CONFIG_NO_HZ_IDLE -- Do those not otherwise specified. (Groups of two.) 11CONFIG_NO_HZ_FULL -- Do two, one with partial CPU enablement. 12CONFIG_PREEMPT -- Do half. (First three and #8.) 13CONFIG_PROVE_LOCKING -- Do several, covering CONFIG_DEBUG_LOCK_ALLOC=y and not. 14CONFIG_PROVE_RCU -- Hardwired to CONFIG_PROVE_LOCKING. 15CONFIG_RCU_BOOST -- one of PREEMPT_RCU. 16CONFIG_RCU_FANOUT -- Cover hierarchy, but overlap with others. 17CONFIG_RCU_FANOUT_LEAF -- Do one non-default. 18CONFIG_RCU_NOCB_CPU -- Do three, one with no rcu_nocbs CPUs, one with 19 rcu_nocbs=0, and one with all rcu_nocbs CPUs. 20CONFIG_RCU_TRACE -- Do half. 21CONFIG_SMP -- Need one !SMP for PREEMPT_RCU. 22CONFIG_RCU_EXPERT=n -- Do a few, but these have to be vanilla configurations. 23CONFIG_RCU_EQS_DEBUG -- Do at least one for CONFIG_NO_HZ_FULL and not. 24 25RCU-bh: Do one with PREEMPT and one with !PREEMPT. 26RCU-sched: Do one with PREEMPT but not BOOST. 27 28 29Boot parameters: 30 31nohz_full - do at least one. 32maxcpu -- do at least one. 33rcupdate.rcu_self_test_bh -- Do at least one each, offloaded and not. 34rcupdate.rcu_self_test_sched -- Do at least one each, offloaded and not. 35rcupdate.rcu_self_test -- Do at least one each, offloaded and not. 36rcutree.rcu_fanout_exact -- Do at least one. 37 38 39Kconfig Parameters Ignored: 40 41CONFIG_64BIT 42 43 Used only to check CONFIG_RCU_FANOUT value, inspection suffices. 44 45CONFIG_PREEMPT_COUNT 46CONFIG_PREEMPT_RCU 47 48 Redundant with CONFIG_PREEMPT, ignore. 49 50CONFIG_RCU_BOOST_DELAY 51 52 Inspection suffices, ignore. 53 54CONFIG_RCU_CPU_STALL_TIMEOUT 55 56 Inspection suffices, ignore. 57 58CONFIG_RCU_STALL_COMMON 59 60 Implied by TREE_RCU and PREEMPT_RCU. 61 62CONFIG_RCU_TORTURE_TEST 63CONFIG_RCU_TORTURE_TEST_RUNNABLE 64 65 Always used in KVM testing. 66 67CONFIG_PREEMPT_RCU 68CONFIG_TREE_RCU 69CONFIG_TINY_RCU 70CONFIG_TASKS_RCU 71 72 These are controlled by CONFIG_PREEMPT and/or CONFIG_SMP. 73 74CONFIG_SRCU 75 76 Selected by CONFIG_RCU_TORTURE_TEST, so cannot disable. 77 78 79boot parameters ignored: TBD 80