CC: kbuild-...@lists.01.org BCC: l...@intel.com CC: "GNU/Weeb Mailing List" <g...@vger.gnuweeb.org> CC: linux-ker...@vger.kernel.org TO: "Paul E. McKenney" <paul...@kernel.org>
tree: https://github.com/ammarfaizi2/linux-block paulmck/linux-rcu/dev.2022.05.18a head: 9735325cf6f7eb6cdcf1ad875b49faa72f288f79 commit: ec0c0f7ea3f62df2f6494b490fe158bcac66a1f1 [64/65] fixup! rcu-tasks: Scan per-CPU lists of RCU Tasks Trace blocked tasks :::::: branch date: 21 hours ago :::::: commit date: 4 days ago config: i386-randconfig-m021 (https://download.01.org/0day-ci/archive/20220524/202205242352.slylyuai-...@intel.com/config) compiler: gcc-11 (Debian 11.3.0-1) 11.3.0 If you fix the issue, kindly add following tag where applicable Reported-by: kernel test robot <l...@intel.com> Reported-by: Dan Carpenter <dan.carpen...@oracle.com> smatch warnings: kernel/rcu/tasks.h:1514 rcu_tasks_trace_pregp_step() error: uninitialized symbol 'rtpcp'. vim +/rtpcp +1514 kernel/rcu/tasks.h b2a7e376a9dcfa Paul E. McKenney 2022-05-18 1469 d5f177d35c2442 Paul E. McKenney 2020-03-09 1470 /* Initialize for a new RCU-tasks-trace grace period. */ b2a7e376a9dcfa Paul E. McKenney 2022-05-18 1471 static void rcu_tasks_trace_pregp_step(struct list_head *hop) d5f177d35c2442 Paul E. McKenney 2020-03-09 1472 { ec0c0f7ea3f62d Paul E. McKenney 2022-05-20 1473 LIST_HEAD(blkd_tasks); d5f177d35c2442 Paul E. McKenney 2020-03-09 1474 int cpu; ec0c0f7ea3f62d Paul E. McKenney 2022-05-20 1475 unsigned long flags; ec0c0f7ea3f62d Paul E. McKenney 2022-05-20 1476 struct rcu_tasks_percpu *rtpcp; ec0c0f7ea3f62d Paul E. McKenney 2022-05-20 1477 struct task_struct *t; d5f177d35c2442 Paul E. McKenney 2020-03-09 1478 d5f177d35c2442 Paul E. McKenney 2020-03-09 1479 // Allow for fast-acting IPIs. d5f177d35c2442 Paul E. McKenney 2020-03-09 1480 atomic_set(&trc_n_readers_need_end, 1); d5f177d35c2442 Paul E. McKenney 2020-03-09 1481 d5f177d35c2442 Paul E. McKenney 2020-03-09 1482 // There shouldn't be any old IPIs, but... d5f177d35c2442 Paul E. McKenney 2020-03-09 1483 for_each_possible_cpu(cpu) d5f177d35c2442 Paul E. McKenney 2020-03-09 1484 WARN_ON_ONCE(per_cpu(trc_ipi_to_cpu, cpu)); 81b4a7bc3b54b0 Paul E. McKenney 2020-03-22 1485 81b4a7bc3b54b0 Paul E. McKenney 2020-03-22 1486 // Disable CPU hotplug across the tasklist scan. 81b4a7bc3b54b0 Paul E. McKenney 2020-03-22 1487 // This also waits for all readers in CPU-hotplug code paths. 81b4a7bc3b54b0 Paul E. McKenney 2020-03-22 1488 cpus_read_lock(); b2a7e376a9dcfa Paul E. McKenney 2022-05-18 1489 b2a7e376a9dcfa Paul E. McKenney 2022-05-18 1490 // These smp_call_function_single() calls are serialized to b2a7e376a9dcfa Paul E. McKenney 2022-05-18 1491 // allow safe access to the hop list. b2a7e376a9dcfa Paul E. McKenney 2022-05-18 1492 for_each_possible_cpu(cpu) b2a7e376a9dcfa Paul E. McKenney 2022-05-18 1493 smp_call_function_single(cpu, rcu_tasks_trace_pertask_handler, hop, 1); ec0c0f7ea3f62d Paul E. McKenney 2022-05-20 1494 ec0c0f7ea3f62d Paul E. McKenney 2022-05-20 1495 // Only after all running tasks have been accounted for is it ec0c0f7ea3f62d Paul E. McKenney 2022-05-20 1496 // safe to take care of the tasks that have blocked within their ec0c0f7ea3f62d Paul E. McKenney 2022-05-20 1497 // current RCU tasks trace read-side critical section. ec0c0f7ea3f62d Paul E. McKenney 2022-05-20 1498 for_each_possible_cpu(cpu) { ec0c0f7ea3f62d Paul E. McKenney 2022-05-20 1499 rtpcp = per_cpu_ptr(rcu_tasks_trace.rtpcpu, cpu); ec0c0f7ea3f62d Paul E. McKenney 2022-05-20 1500 raw_spin_lock_irqsave_rcu_node(rtpcp, flags); ec0c0f7ea3f62d Paul E. McKenney 2022-05-20 1501 list_splice_init(&rtpcp->rtp_blkd_tasks, &blkd_tasks); ec0c0f7ea3f62d Paul E. McKenney 2022-05-20 1502 while (!list_empty(&blkd_tasks)) { ec0c0f7ea3f62d Paul E. McKenney 2022-05-20 1503 t = list_first_entry(&blkd_tasks, struct task_struct, trc_blkd_node); ec0c0f7ea3f62d Paul E. McKenney 2022-05-20 1504 list_del_init(&t->trc_blkd_node); ec0c0f7ea3f62d Paul E. McKenney 2022-05-20 1505 list_add(&t->trc_blkd_node, &rtpcp->rtp_blkd_tasks); ec0c0f7ea3f62d Paul E. McKenney 2022-05-20 1506 raw_spin_unlock_irqrestore_rcu_node(rtpcp, flags); ec0c0f7ea3f62d Paul E. McKenney 2022-05-20 1507 rcu_tasks_trace_pertask(t, hop); ec0c0f7ea3f62d Paul E. McKenney 2022-05-20 1508 raw_spin_lock_irqsave_rcu_node(rtpcp, flags); ec0c0f7ea3f62d Paul E. McKenney 2022-05-20 1509 } ec0c0f7ea3f62d Paul E. McKenney 2022-05-20 1510 raw_spin_unlock_irqrestore_rcu_node(rtpcp, flags); ec0c0f7ea3f62d Paul E. McKenney 2022-05-20 1511 } ec0c0f7ea3f62d Paul E. McKenney 2022-05-20 1512 // Pull in the tasks that blocked on this CPU while in their ec0c0f7ea3f62d Paul E. McKenney 2022-05-20 1513 // current RCU tasks trace read-side critical section. ec0c0f7ea3f62d Paul E. McKenney 2022-05-20 @1514 raw_spin_lock_irqsave_rcu_node(rtpcp, flags); ec0c0f7ea3f62d Paul E. McKenney 2022-05-20 1515 list_for_each_entry(t, &rtpcp->rtp_blkd_tasks, trc_blkd_node) ec0c0f7ea3f62d Paul E. McKenney 2022-05-20 1516 if (rcu_tasks_trace_pertask_prep(t)) ec0c0f7ea3f62d Paul E. McKenney 2022-05-20 1517 trc_add_holdout(t, hop); ec0c0f7ea3f62d Paul E. McKenney 2022-05-20 1518 raw_spin_unlock_irqrestore_rcu_node(rtpcp, flags); d5f177d35c2442 Paul E. McKenney 2020-03-09 1519 } d5f177d35c2442 Paul E. McKenney 2020-03-09 1520 -- 0-DAY CI Kernel Test Service https://01.org/lkp _______________________________________________ kbuild mailing list -- kbuild@lists.01.org To unsubscribe send an email to kbuild-le...@lists.01.org
