14102adabSPaul E. McKenney /* 24102adabSPaul E. McKenney * Read-Copy Update mechanism for mutual exclusion (tree-based version) 34102adabSPaul E. McKenney * Internal non-public definitions. 44102adabSPaul E. McKenney * 54102adabSPaul E. McKenney * This program is free software; you can redistribute it and/or modify 64102adabSPaul E. McKenney * it under the terms of the GNU General Public License as published by 74102adabSPaul E. McKenney * the Free Software Foundation; either version 2 of the License, or 84102adabSPaul E. McKenney * (at your option) any later version. 94102adabSPaul E. McKenney * 104102adabSPaul E. McKenney * This program is distributed in the hope that it will be useful, 114102adabSPaul E. McKenney * but WITHOUT ANY WARRANTY; without even the implied warranty of 124102adabSPaul E. McKenney * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 134102adabSPaul E. McKenney * GNU General Public License for more details. 144102adabSPaul E. McKenney * 154102adabSPaul E. McKenney * You should have received a copy of the GNU General Public License 1687de1cfdSPaul E. McKenney * along with this program; if not, you can access it online at 1787de1cfdSPaul E. McKenney * http://www.gnu.org/licenses/gpl-2.0.html. 184102adabSPaul E. McKenney * 194102adabSPaul E. McKenney * Copyright IBM Corporation, 2008 204102adabSPaul E. McKenney * 214102adabSPaul E. McKenney * Author: Ingo Molnar <mingo@elte.hu> 224102adabSPaul E. McKenney * Paul E. McKenney <paulmck@linux.vnet.ibm.com> 234102adabSPaul E. McKenney */ 244102adabSPaul E. McKenney 254102adabSPaul E. McKenney #include <linux/cache.h> 264102adabSPaul E. McKenney #include <linux/spinlock.h> 274102adabSPaul E. McKenney #include <linux/threads.h> 284102adabSPaul E. McKenney #include <linux/cpumask.h> 294102adabSPaul E. McKenney #include <linux/seqlock.h> 304102adabSPaul E. McKenney #include <linux/irq_work.h> 314102adabSPaul E. McKenney 324102adabSPaul E. McKenney /* 334102adabSPaul E. McKenney * Define shape of hierarchy based on NR_CPUS, CONFIG_RCU_FANOUT, and 344102adabSPaul E. McKenney * CONFIG_RCU_FANOUT_LEAF. 354102adabSPaul E. McKenney * In theory, it should be possible to add more levels straightforwardly. 364102adabSPaul E. McKenney * In practice, this did work well going from three levels to four. 374102adabSPaul E. McKenney * Of course, your mileage may vary. 384102adabSPaul E. McKenney */ 394102adabSPaul E. McKenney #define MAX_RCU_LVLS 4 404102adabSPaul E. McKenney #define RCU_FANOUT_1 (CONFIG_RCU_FANOUT_LEAF) 414102adabSPaul E. McKenney #define RCU_FANOUT_2 (RCU_FANOUT_1 * CONFIG_RCU_FANOUT) 424102adabSPaul E. McKenney #define RCU_FANOUT_3 (RCU_FANOUT_2 * CONFIG_RCU_FANOUT) 434102adabSPaul E. McKenney #define RCU_FANOUT_4 (RCU_FANOUT_3 * CONFIG_RCU_FANOUT) 444102adabSPaul E. McKenney 454102adabSPaul E. McKenney #if NR_CPUS <= RCU_FANOUT_1 464102adabSPaul E. McKenney # define RCU_NUM_LVLS 1 474102adabSPaul E. McKenney # define NUM_RCU_LVL_0 1 484102adabSPaul E. McKenney # define NUM_RCU_LVL_1 (NR_CPUS) 494102adabSPaul E. McKenney # define NUM_RCU_LVL_2 0 504102adabSPaul E. McKenney # define NUM_RCU_LVL_3 0 514102adabSPaul E. McKenney # define NUM_RCU_LVL_4 0 524102adabSPaul E. McKenney #elif NR_CPUS <= RCU_FANOUT_2 534102adabSPaul E. McKenney # define RCU_NUM_LVLS 2 544102adabSPaul E. McKenney # define NUM_RCU_LVL_0 1 554102adabSPaul E. McKenney # define NUM_RCU_LVL_1 DIV_ROUND_UP(NR_CPUS, RCU_FANOUT_1) 564102adabSPaul E. McKenney # define NUM_RCU_LVL_2 (NR_CPUS) 574102adabSPaul E. McKenney # define NUM_RCU_LVL_3 0 584102adabSPaul E. McKenney # define NUM_RCU_LVL_4 0 594102adabSPaul E. McKenney #elif NR_CPUS <= RCU_FANOUT_3 604102adabSPaul E. McKenney # define RCU_NUM_LVLS 3 614102adabSPaul E. McKenney # define NUM_RCU_LVL_0 1 624102adabSPaul E. McKenney # define NUM_RCU_LVL_1 DIV_ROUND_UP(NR_CPUS, RCU_FANOUT_2) 634102adabSPaul E. McKenney # define NUM_RCU_LVL_2 DIV_ROUND_UP(NR_CPUS, RCU_FANOUT_1) 644102adabSPaul E. McKenney # define NUM_RCU_LVL_3 (NR_CPUS) 654102adabSPaul E. McKenney # define NUM_RCU_LVL_4 0 664102adabSPaul E. McKenney #elif NR_CPUS <= RCU_FANOUT_4 674102adabSPaul E. McKenney # define RCU_NUM_LVLS 4 684102adabSPaul E. McKenney # define NUM_RCU_LVL_0 1 694102adabSPaul E. McKenney # define NUM_RCU_LVL_1 DIV_ROUND_UP(NR_CPUS, RCU_FANOUT_3) 704102adabSPaul E. McKenney # define NUM_RCU_LVL_2 DIV_ROUND_UP(NR_CPUS, RCU_FANOUT_2) 714102adabSPaul E. McKenney # define NUM_RCU_LVL_3 DIV_ROUND_UP(NR_CPUS, RCU_FANOUT_1) 724102adabSPaul E. McKenney # define NUM_RCU_LVL_4 (NR_CPUS) 734102adabSPaul E. McKenney #else 744102adabSPaul E. McKenney # error "CONFIG_RCU_FANOUT insufficient for NR_CPUS" 754102adabSPaul E. McKenney #endif /* #if (NR_CPUS) <= RCU_FANOUT_1 */ 764102adabSPaul E. McKenney 774102adabSPaul E. McKenney #define RCU_SUM (NUM_RCU_LVL_0 + NUM_RCU_LVL_1 + NUM_RCU_LVL_2 + NUM_RCU_LVL_3 + NUM_RCU_LVL_4) 784102adabSPaul E. McKenney #define NUM_RCU_NODES (RCU_SUM - NR_CPUS) 794102adabSPaul E. McKenney 804102adabSPaul E. McKenney extern int rcu_num_lvls; 814102adabSPaul E. McKenney extern int rcu_num_nodes; 824102adabSPaul E. McKenney 834102adabSPaul E. McKenney /* 844102adabSPaul E. McKenney * Dynticks per-CPU state. 854102adabSPaul E. McKenney */ 864102adabSPaul E. McKenney struct rcu_dynticks { 874102adabSPaul E. McKenney long long dynticks_nesting; /* Track irq/process nesting level. */ 884102adabSPaul E. McKenney /* Process level is worth LLONG_MAX/2. */ 894102adabSPaul E. McKenney int dynticks_nmi_nesting; /* Track NMI nesting level. */ 904102adabSPaul E. McKenney atomic_t dynticks; /* Even value for idle, else odd. */ 914102adabSPaul E. McKenney #ifdef CONFIG_NO_HZ_FULL_SYSIDLE 924102adabSPaul E. McKenney long long dynticks_idle_nesting; 934102adabSPaul E. McKenney /* irq/process nesting level from idle. */ 944102adabSPaul E. McKenney atomic_t dynticks_idle; /* Even value for idle, else odd. */ 954102adabSPaul E. McKenney /* "Idle" excludes userspace execution. */ 964102adabSPaul E. McKenney unsigned long dynticks_idle_jiffies; 974102adabSPaul E. McKenney /* End of last non-NMI non-idle period. */ 984102adabSPaul E. McKenney #endif /* #ifdef CONFIG_NO_HZ_FULL_SYSIDLE */ 994102adabSPaul E. McKenney #ifdef CONFIG_RCU_FAST_NO_HZ 1004102adabSPaul E. McKenney bool all_lazy; /* Are all CPU's CBs lazy? */ 1014102adabSPaul E. McKenney unsigned long nonlazy_posted; 1024102adabSPaul E. McKenney /* # times non-lazy CBs posted to CPU. */ 1034102adabSPaul E. McKenney unsigned long nonlazy_posted_snap; 1044102adabSPaul E. McKenney /* idle-period nonlazy_posted snapshot. */ 1054102adabSPaul E. McKenney unsigned long last_accelerate; 1064102adabSPaul E. McKenney /* Last jiffy CBs were accelerated. */ 1074102adabSPaul E. McKenney unsigned long last_advance_all; 1084102adabSPaul E. McKenney /* Last jiffy CBs were all advanced. */ 1094102adabSPaul E. McKenney int tick_nohz_enabled_snap; /* Previously seen value from sysfs. */ 1104102adabSPaul E. McKenney #endif /* #ifdef CONFIG_RCU_FAST_NO_HZ */ 1114102adabSPaul E. McKenney }; 1124102adabSPaul E. McKenney 1134102adabSPaul E. McKenney /* RCU's kthread states for tracing. */ 1144102adabSPaul E. McKenney #define RCU_KTHREAD_STOPPED 0 1154102adabSPaul E. McKenney #define RCU_KTHREAD_RUNNING 1 1164102adabSPaul E. McKenney #define RCU_KTHREAD_WAITING 2 1174102adabSPaul E. McKenney #define RCU_KTHREAD_OFFCPU 3 1184102adabSPaul E. McKenney #define RCU_KTHREAD_YIELDING 4 1194102adabSPaul E. McKenney #define RCU_KTHREAD_MAX 4 1204102adabSPaul E. McKenney 1214102adabSPaul E. McKenney /* 1224102adabSPaul E. McKenney * Definition for node within the RCU grace-period-detection hierarchy. 1234102adabSPaul E. McKenney */ 1244102adabSPaul E. McKenney struct rcu_node { 1254102adabSPaul E. McKenney raw_spinlock_t lock; /* Root rcu_node's lock protects some */ 1264102adabSPaul E. McKenney /* rcu_state fields as well as following. */ 1274102adabSPaul E. McKenney unsigned long gpnum; /* Current grace period for this node. */ 1284102adabSPaul E. McKenney /* This will either be equal to or one */ 1294102adabSPaul E. McKenney /* behind the root rcu_node's gpnum. */ 1304102adabSPaul E. McKenney unsigned long completed; /* Last GP completed for this node. */ 1314102adabSPaul E. McKenney /* This will either be equal to or one */ 1324102adabSPaul E. McKenney /* behind the root rcu_node's gpnum. */ 1334102adabSPaul E. McKenney unsigned long qsmask; /* CPUs or groups that need to switch in */ 1344102adabSPaul E. McKenney /* order for current grace period to proceed.*/ 1354102adabSPaul E. McKenney /* In leaf rcu_node, each bit corresponds to */ 1364102adabSPaul E. McKenney /* an rcu_data structure, otherwise, each */ 1374102adabSPaul E. McKenney /* bit corresponds to a child rcu_node */ 1384102adabSPaul E. McKenney /* structure. */ 1394102adabSPaul E. McKenney unsigned long expmask; /* Groups that have ->blkd_tasks */ 1404102adabSPaul E. McKenney /* elements that need to drain to allow the */ 1414102adabSPaul E. McKenney /* current expedited grace period to */ 14228f6569aSPranith Kumar /* complete (only for PREEMPT_RCU). */ 1434102adabSPaul E. McKenney unsigned long qsmaskinit; 1444102adabSPaul E. McKenney /* Per-GP initial value for qsmask & expmask. */ 1454102adabSPaul E. McKenney unsigned long grpmask; /* Mask to apply to parent qsmask. */ 1464102adabSPaul E. McKenney /* Only one bit will be set in this mask. */ 1474102adabSPaul E. McKenney int grplo; /* lowest-numbered CPU or group here. */ 1484102adabSPaul E. McKenney int grphi; /* highest-numbered CPU or group here. */ 1494102adabSPaul E. McKenney u8 grpnum; /* CPU/group number for next level up. */ 1504102adabSPaul E. McKenney u8 level; /* root is at level 0. */ 1514102adabSPaul E. McKenney struct rcu_node *parent; 1524102adabSPaul E. McKenney struct list_head blkd_tasks; 1534102adabSPaul E. McKenney /* Tasks blocked in RCU read-side critical */ 1544102adabSPaul E. McKenney /* section. Tasks are placed at the head */ 1554102adabSPaul E. McKenney /* of this list and age towards the tail. */ 1564102adabSPaul E. McKenney struct list_head *gp_tasks; 1574102adabSPaul E. McKenney /* Pointer to the first task blocking the */ 1584102adabSPaul E. McKenney /* current grace period, or NULL if there */ 1594102adabSPaul E. McKenney /* is no such task. */ 1604102adabSPaul E. McKenney struct list_head *exp_tasks; 1614102adabSPaul E. McKenney /* Pointer to the first task blocking the */ 1624102adabSPaul E. McKenney /* current expedited grace period, or NULL */ 1634102adabSPaul E. McKenney /* if there is no such task. If there */ 1644102adabSPaul E. McKenney /* is no current expedited grace period, */ 1654102adabSPaul E. McKenney /* then there can cannot be any such task. */ 1664102adabSPaul E. McKenney #ifdef CONFIG_RCU_BOOST 1674102adabSPaul E. McKenney struct list_head *boost_tasks; 1684102adabSPaul E. McKenney /* Pointer to first task that needs to be */ 1694102adabSPaul E. McKenney /* priority boosted, or NULL if no priority */ 1704102adabSPaul E. McKenney /* boosting is needed for this rcu_node */ 1714102adabSPaul E. McKenney /* structure. If there are no tasks */ 1724102adabSPaul E. McKenney /* queued on this rcu_node structure that */ 1734102adabSPaul E. McKenney /* are blocking the current grace period, */ 1744102adabSPaul E. McKenney /* there can be no such task. */ 175dfeb9765SPaul E. McKenney struct completion boost_completion; 176dfeb9765SPaul E. McKenney /* Used to ensure that the rt_mutex used */ 177dfeb9765SPaul E. McKenney /* to carry out the boosting is fully */ 178dfeb9765SPaul E. McKenney /* released with no future boostee accesses */ 179dfeb9765SPaul E. McKenney /* before that rt_mutex is re-initialized. */ 180abaa93d9SPaul E. McKenney struct rt_mutex boost_mtx; 181abaa93d9SPaul E. McKenney /* Used only for the priority-boosting */ 182abaa93d9SPaul E. McKenney /* side effect, not as a lock. */ 1834102adabSPaul E. McKenney unsigned long boost_time; 1844102adabSPaul E. McKenney /* When to start boosting (jiffies). */ 1854102adabSPaul E. McKenney struct task_struct *boost_kthread_task; 1864102adabSPaul E. McKenney /* kthread that takes care of priority */ 1874102adabSPaul E. McKenney /* boosting for this rcu_node structure. */ 1884102adabSPaul E. McKenney unsigned int boost_kthread_status; 1894102adabSPaul E. McKenney /* State of boost_kthread_task for tracing. */ 1904102adabSPaul E. McKenney unsigned long n_tasks_boosted; 1914102adabSPaul E. McKenney /* Total number of tasks boosted. */ 1924102adabSPaul E. McKenney unsigned long n_exp_boosts; 1934102adabSPaul E. McKenney /* Number of tasks boosted for expedited GP. */ 1944102adabSPaul E. McKenney unsigned long n_normal_boosts; 1954102adabSPaul E. McKenney /* Number of tasks boosted for normal GP. */ 1964102adabSPaul E. McKenney unsigned long n_balk_blkd_tasks; 1974102adabSPaul E. McKenney /* Refused to boost: no blocked tasks. */ 1984102adabSPaul E. McKenney unsigned long n_balk_exp_gp_tasks; 1994102adabSPaul E. McKenney /* Refused to boost: nothing blocking GP. */ 2004102adabSPaul E. McKenney unsigned long n_balk_boost_tasks; 2014102adabSPaul E. McKenney /* Refused to boost: already boosting. */ 2024102adabSPaul E. McKenney unsigned long n_balk_notblocked; 2034102adabSPaul E. McKenney /* Refused to boost: RCU RS CS still running. */ 2044102adabSPaul E. McKenney unsigned long n_balk_notyet; 2054102adabSPaul E. McKenney /* Refused to boost: not yet time. */ 2064102adabSPaul E. McKenney unsigned long n_balk_nos; 2074102adabSPaul E. McKenney /* Refused to boost: not sure why, though. */ 2084102adabSPaul E. McKenney /* This can happen due to race conditions. */ 2094102adabSPaul E. McKenney #endif /* #ifdef CONFIG_RCU_BOOST */ 2104102adabSPaul E. McKenney #ifdef CONFIG_RCU_NOCB_CPU 2114102adabSPaul E. McKenney wait_queue_head_t nocb_gp_wq[2]; 2124102adabSPaul E. McKenney /* Place for rcu_nocb_kthread() to wait GP. */ 2134102adabSPaul E. McKenney #endif /* #ifdef CONFIG_RCU_NOCB_CPU */ 2144102adabSPaul E. McKenney int need_future_gp[2]; 2154102adabSPaul E. McKenney /* Counts of upcoming no-CB GP requests. */ 2164102adabSPaul E. McKenney raw_spinlock_t fqslock ____cacheline_internodealigned_in_smp; 2174102adabSPaul E. McKenney } ____cacheline_internodealigned_in_smp; 2184102adabSPaul E. McKenney 2194102adabSPaul E. McKenney /* 2204102adabSPaul E. McKenney * Do a full breadth-first scan of the rcu_node structures for the 2214102adabSPaul E. McKenney * specified rcu_state structure. 2224102adabSPaul E. McKenney */ 2234102adabSPaul E. McKenney #define rcu_for_each_node_breadth_first(rsp, rnp) \ 2244102adabSPaul E. McKenney for ((rnp) = &(rsp)->node[0]; \ 2254102adabSPaul E. McKenney (rnp) < &(rsp)->node[rcu_num_nodes]; (rnp)++) 2264102adabSPaul E. McKenney 2274102adabSPaul E. McKenney /* 2284102adabSPaul E. McKenney * Do a breadth-first scan of the non-leaf rcu_node structures for the 2294102adabSPaul E. McKenney * specified rcu_state structure. Note that if there is a singleton 2304102adabSPaul E. McKenney * rcu_node tree with but one rcu_node structure, this loop is a no-op. 2314102adabSPaul E. McKenney */ 2324102adabSPaul E. McKenney #define rcu_for_each_nonleaf_node_breadth_first(rsp, rnp) \ 2334102adabSPaul E. McKenney for ((rnp) = &(rsp)->node[0]; \ 2344102adabSPaul E. McKenney (rnp) < (rsp)->level[rcu_num_lvls - 1]; (rnp)++) 2354102adabSPaul E. McKenney 2364102adabSPaul E. McKenney /* 2374102adabSPaul E. McKenney * Scan the leaves of the rcu_node hierarchy for the specified rcu_state 2384102adabSPaul E. McKenney * structure. Note that if there is a singleton rcu_node tree with but 2394102adabSPaul E. McKenney * one rcu_node structure, this loop -will- visit the rcu_node structure. 2404102adabSPaul E. McKenney * It is still a leaf node, even if it is also the root node. 2414102adabSPaul E. McKenney */ 2424102adabSPaul E. McKenney #define rcu_for_each_leaf_node(rsp, rnp) \ 2434102adabSPaul E. McKenney for ((rnp) = (rsp)->level[rcu_num_lvls - 1]; \ 2444102adabSPaul E. McKenney (rnp) < &(rsp)->node[rcu_num_nodes]; (rnp)++) 2454102adabSPaul E. McKenney 2464102adabSPaul E. McKenney /* Index values for nxttail array in struct rcu_data. */ 2474102adabSPaul E. McKenney #define RCU_DONE_TAIL 0 /* Also RCU_WAIT head. */ 2484102adabSPaul E. McKenney #define RCU_WAIT_TAIL 1 /* Also RCU_NEXT_READY head. */ 2494102adabSPaul E. McKenney #define RCU_NEXT_READY_TAIL 2 /* Also RCU_NEXT head. */ 2504102adabSPaul E. McKenney #define RCU_NEXT_TAIL 3 2514102adabSPaul E. McKenney #define RCU_NEXT_SIZE 4 2524102adabSPaul E. McKenney 2534102adabSPaul E. McKenney /* Per-CPU data for read-copy update. */ 2544102adabSPaul E. McKenney struct rcu_data { 2554102adabSPaul E. McKenney /* 1) quiescent-state and grace-period handling : */ 2564102adabSPaul E. McKenney unsigned long completed; /* Track rsp->completed gp number */ 2574102adabSPaul E. McKenney /* in order to detect GP end. */ 2584102adabSPaul E. McKenney unsigned long gpnum; /* Highest gp number that this CPU */ 2594102adabSPaul E. McKenney /* is aware of having started. */ 260*5cd37193SPaul E. McKenney unsigned long rcu_qs_ctr_snap;/* Snapshot of rcu_qs_ctr to check */ 261*5cd37193SPaul E. McKenney /* for rcu_all_qs() invocations. */ 2624102adabSPaul E. McKenney bool passed_quiesce; /* User-mode/idle loop etc. */ 2634102adabSPaul E. McKenney bool qs_pending; /* Core waits for quiesc state. */ 2644102adabSPaul E. McKenney bool beenonline; /* CPU online at least once. */ 265e3663b10SPaul E. McKenney bool gpwrap; /* Possible gpnum/completed wrap. */ 2664102adabSPaul E. McKenney struct rcu_node *mynode; /* This CPU's leaf of hierarchy */ 2674102adabSPaul E. McKenney unsigned long grpmask; /* Mask to apply to leaf qsmask. */ 2684102adabSPaul E. McKenney #ifdef CONFIG_RCU_CPU_STALL_INFO 2694102adabSPaul E. McKenney unsigned long ticks_this_gp; /* The number of scheduling-clock */ 2704102adabSPaul E. McKenney /* ticks this CPU has handled */ 2714102adabSPaul E. McKenney /* during and after the last grace */ 2724102adabSPaul E. McKenney /* period it is aware of. */ 2734102adabSPaul E. McKenney #endif /* #ifdef CONFIG_RCU_CPU_STALL_INFO */ 2744102adabSPaul E. McKenney 2754102adabSPaul E. McKenney /* 2) batch handling */ 2764102adabSPaul E. McKenney /* 2774102adabSPaul E. McKenney * If nxtlist is not NULL, it is partitioned as follows. 2784102adabSPaul E. McKenney * Any of the partitions might be empty, in which case the 2794102adabSPaul E. McKenney * pointer to that partition will be equal to the pointer for 2804102adabSPaul E. McKenney * the following partition. When the list is empty, all of 2814102adabSPaul E. McKenney * the nxttail elements point to the ->nxtlist pointer itself, 2824102adabSPaul E. McKenney * which in that case is NULL. 2834102adabSPaul E. McKenney * 2844102adabSPaul E. McKenney * [nxtlist, *nxttail[RCU_DONE_TAIL]): 2854102adabSPaul E. McKenney * Entries that batch # <= ->completed 2864102adabSPaul E. McKenney * The grace period for these entries has completed, and 2874102adabSPaul E. McKenney * the other grace-period-completed entries may be moved 2884102adabSPaul E. McKenney * here temporarily in rcu_process_callbacks(). 2894102adabSPaul E. McKenney * [*nxttail[RCU_DONE_TAIL], *nxttail[RCU_WAIT_TAIL]): 2904102adabSPaul E. McKenney * Entries that batch # <= ->completed - 1: waiting for current GP 2914102adabSPaul E. McKenney * [*nxttail[RCU_WAIT_TAIL], *nxttail[RCU_NEXT_READY_TAIL]): 2924102adabSPaul E. McKenney * Entries known to have arrived before current GP ended 2934102adabSPaul E. McKenney * [*nxttail[RCU_NEXT_READY_TAIL], *nxttail[RCU_NEXT_TAIL]): 2944102adabSPaul E. McKenney * Entries that might have arrived after current GP ended 2954102adabSPaul E. McKenney * Note that the value of *nxttail[RCU_NEXT_TAIL] will 2964102adabSPaul E. McKenney * always be NULL, as this is the end of the list. 2974102adabSPaul E. McKenney */ 2984102adabSPaul E. McKenney struct rcu_head *nxtlist; 2994102adabSPaul E. McKenney struct rcu_head **nxttail[RCU_NEXT_SIZE]; 3004102adabSPaul E. McKenney unsigned long nxtcompleted[RCU_NEXT_SIZE]; 3014102adabSPaul E. McKenney /* grace periods for sublists. */ 3024102adabSPaul E. McKenney long qlen_lazy; /* # of lazy queued callbacks */ 3034102adabSPaul E. McKenney long qlen; /* # of queued callbacks, incl lazy */ 3044102adabSPaul E. McKenney long qlen_last_fqs_check; 3054102adabSPaul E. McKenney /* qlen at last check for QS forcing */ 3064102adabSPaul E. McKenney unsigned long n_cbs_invoked; /* count of RCU cbs invoked. */ 3074102adabSPaul E. McKenney unsigned long n_nocbs_invoked; /* count of no-CBs RCU cbs invoked. */ 3084102adabSPaul E. McKenney unsigned long n_cbs_orphaned; /* RCU cbs orphaned by dying CPU */ 3094102adabSPaul E. McKenney unsigned long n_cbs_adopted; /* RCU cbs adopted from dying CPU */ 3104102adabSPaul E. McKenney unsigned long n_force_qs_snap; 3114102adabSPaul E. McKenney /* did other CPU force QS recently? */ 3124102adabSPaul E. McKenney long blimit; /* Upper limit on a processed batch */ 3134102adabSPaul E. McKenney 3144102adabSPaul E. McKenney /* 3) dynticks interface. */ 3154102adabSPaul E. McKenney struct rcu_dynticks *dynticks; /* Shared per-CPU dynticks state. */ 3164102adabSPaul E. McKenney int dynticks_snap; /* Per-GP tracking for dynticks. */ 3174102adabSPaul E. McKenney 3184102adabSPaul E. McKenney /* 4) reasons this CPU needed to be kicked by force_quiescent_state */ 3194102adabSPaul E. McKenney unsigned long dynticks_fqs; /* Kicked due to dynticks idle. */ 3204102adabSPaul E. McKenney unsigned long offline_fqs; /* Kicked due to being offline. */ 3214a81e832SPaul E. McKenney unsigned long cond_resched_completed; 3224a81e832SPaul E. McKenney /* Grace period that needs help */ 3234a81e832SPaul E. McKenney /* from cond_resched(). */ 3244102adabSPaul E. McKenney 3254102adabSPaul E. McKenney /* 5) __rcu_pending() statistics. */ 3264102adabSPaul E. McKenney unsigned long n_rcu_pending; /* rcu_pending() calls since boot. */ 3274102adabSPaul E. McKenney unsigned long n_rp_qs_pending; 3284102adabSPaul E. McKenney unsigned long n_rp_report_qs; 3294102adabSPaul E. McKenney unsigned long n_rp_cb_ready; 3304102adabSPaul E. McKenney unsigned long n_rp_cpu_needs_gp; 3314102adabSPaul E. McKenney unsigned long n_rp_gp_completed; 3324102adabSPaul E. McKenney unsigned long n_rp_gp_started; 33396d3fd0dSPaul E. McKenney unsigned long n_rp_nocb_defer_wakeup; 3344102adabSPaul E. McKenney unsigned long n_rp_need_nothing; 3354102adabSPaul E. McKenney 3364102adabSPaul E. McKenney /* 6) _rcu_barrier() and OOM callbacks. */ 3374102adabSPaul E. McKenney struct rcu_head barrier_head; 3384102adabSPaul E. McKenney #ifdef CONFIG_RCU_FAST_NO_HZ 3394102adabSPaul E. McKenney struct rcu_head oom_head; 3404102adabSPaul E. McKenney #endif /* #ifdef CONFIG_RCU_FAST_NO_HZ */ 3414102adabSPaul E. McKenney 3424102adabSPaul E. McKenney /* 7) Callback offloading. */ 3434102adabSPaul E. McKenney #ifdef CONFIG_RCU_NOCB_CPU 3444102adabSPaul E. McKenney struct rcu_head *nocb_head; /* CBs waiting for kthread. */ 3454102adabSPaul E. McKenney struct rcu_head **nocb_tail; 3464102adabSPaul E. McKenney atomic_long_t nocb_q_count; /* # CBs waiting for kthread */ 3474102adabSPaul E. McKenney atomic_long_t nocb_q_count_lazy; /* (approximate). */ 348fbce7497SPaul E. McKenney struct rcu_head *nocb_follower_head; /* CBs ready to invoke. */ 349fbce7497SPaul E. McKenney struct rcu_head **nocb_follower_tail; 350fbce7497SPaul E. McKenney atomic_long_t nocb_follower_count; /* # CBs ready to invoke. */ 351fbce7497SPaul E. McKenney atomic_long_t nocb_follower_count_lazy; /* (approximate). */ 3524102adabSPaul E. McKenney int nocb_p_count; /* # CBs being invoked by kthread */ 3534102adabSPaul E. McKenney int nocb_p_count_lazy; /* (approximate). */ 3544102adabSPaul E. McKenney wait_queue_head_t nocb_wq; /* For nocb kthreads to sleep on. */ 3554102adabSPaul E. McKenney struct task_struct *nocb_kthread; 3569fdd3bc9SPaul E. McKenney int nocb_defer_wakeup; /* Defer wakeup of nocb_kthread. */ 357fbce7497SPaul E. McKenney 358fbce7497SPaul E. McKenney /* The following fields are used by the leader, hence own cacheline. */ 359fbce7497SPaul E. McKenney struct rcu_head *nocb_gp_head ____cacheline_internodealigned_in_smp; 360fbce7497SPaul E. McKenney /* CBs waiting for GP. */ 361fbce7497SPaul E. McKenney struct rcu_head **nocb_gp_tail; 362fbce7497SPaul E. McKenney long nocb_gp_count; 363fbce7497SPaul E. McKenney long nocb_gp_count_lazy; 36411ed7f93SPranith Kumar bool nocb_leader_sleep; /* Is the nocb leader thread asleep? */ 365fbce7497SPaul E. McKenney struct rcu_data *nocb_next_follower; 366fbce7497SPaul E. McKenney /* Next follower in wakeup chain. */ 367fbce7497SPaul E. McKenney 368fbce7497SPaul E. McKenney /* The following fields are used by the follower, hence new cachline. */ 369fbce7497SPaul E. McKenney struct rcu_data *nocb_leader ____cacheline_internodealigned_in_smp; 370fbce7497SPaul E. McKenney /* Leader CPU takes GP-end wakeups. */ 3714102adabSPaul E. McKenney #endif /* #ifdef CONFIG_RCU_NOCB_CPU */ 3724102adabSPaul E. McKenney 3734102adabSPaul E. McKenney /* 8) RCU CPU stall data. */ 3744102adabSPaul E. McKenney #ifdef CONFIG_RCU_CPU_STALL_INFO 3754102adabSPaul E. McKenney unsigned int softirq_snap; /* Snapshot of softirq activity. */ 3764102adabSPaul E. McKenney #endif /* #ifdef CONFIG_RCU_CPU_STALL_INFO */ 3774102adabSPaul E. McKenney 3784102adabSPaul E. McKenney int cpu; 3794102adabSPaul E. McKenney struct rcu_state *rsp; 3804102adabSPaul E. McKenney }; 3814102adabSPaul E. McKenney 3824102adabSPaul E. McKenney /* Values for fqs_state field in struct rcu_state. */ 3834102adabSPaul E. McKenney #define RCU_GP_IDLE 0 /* No grace period in progress. */ 3844102adabSPaul E. McKenney #define RCU_GP_INIT 1 /* Grace period being initialized. */ 3854102adabSPaul E. McKenney #define RCU_SAVE_DYNTICK 2 /* Need to scan dyntick state. */ 3864102adabSPaul E. McKenney #define RCU_FORCE_QS 3 /* Need to force quiescent state. */ 3874102adabSPaul E. McKenney #define RCU_SIGNAL_INIT RCU_SAVE_DYNTICK 3884102adabSPaul E. McKenney 3899fdd3bc9SPaul E. McKenney /* Values for nocb_defer_wakeup field in struct rcu_data. */ 3909fdd3bc9SPaul E. McKenney #define RCU_NOGP_WAKE_NOT 0 3919fdd3bc9SPaul E. McKenney #define RCU_NOGP_WAKE 1 3929fdd3bc9SPaul E. McKenney #define RCU_NOGP_WAKE_FORCE 2 3939fdd3bc9SPaul E. McKenney 3944102adabSPaul E. McKenney #define RCU_JIFFIES_TILL_FORCE_QS (1 + (HZ > 250) + (HZ > 500)) 3954102adabSPaul E. McKenney /* For jiffies_till_first_fqs and */ 3964102adabSPaul E. McKenney /* and jiffies_till_next_fqs. */ 3974102adabSPaul E. McKenney 3984102adabSPaul E. McKenney #define RCU_JIFFIES_FQS_DIV 256 /* Very large systems need more */ 3994102adabSPaul E. McKenney /* delay between bouts of */ 4004102adabSPaul E. McKenney /* quiescent-state forcing. */ 4014102adabSPaul E. McKenney 4024102adabSPaul E. McKenney #define RCU_STALL_RAT_DELAY 2 /* Allow other CPUs time to take */ 4034102adabSPaul E. McKenney /* at least one scheduling clock */ 4044102adabSPaul E. McKenney /* irq before ratting on them. */ 4054102adabSPaul E. McKenney 4064102adabSPaul E. McKenney #define rcu_wait(cond) \ 4074102adabSPaul E. McKenney do { \ 4084102adabSPaul E. McKenney for (;;) { \ 4094102adabSPaul E. McKenney set_current_state(TASK_INTERRUPTIBLE); \ 4104102adabSPaul E. McKenney if (cond) \ 4114102adabSPaul E. McKenney break; \ 4124102adabSPaul E. McKenney schedule(); \ 4134102adabSPaul E. McKenney } \ 4144102adabSPaul E. McKenney __set_current_state(TASK_RUNNING); \ 4154102adabSPaul E. McKenney } while (0) 4164102adabSPaul E. McKenney 4174102adabSPaul E. McKenney /* 4184102adabSPaul E. McKenney * RCU global state, including node hierarchy. This hierarchy is 4194102adabSPaul E. McKenney * represented in "heap" form in a dense array. The root (first level) 4204102adabSPaul E. McKenney * of the hierarchy is in ->node[0] (referenced by ->level[0]), the second 4214102adabSPaul E. McKenney * level in ->node[1] through ->node[m] (->node[1] referenced by ->level[1]), 4224102adabSPaul E. McKenney * and the third level in ->node[m+1] and following (->node[m+1] referenced 4234102adabSPaul E. McKenney * by ->level[2]). The number of levels is determined by the number of 4244102adabSPaul E. McKenney * CPUs and by CONFIG_RCU_FANOUT. Small systems will have a "hierarchy" 4254102adabSPaul E. McKenney * consisting of a single rcu_node. 4264102adabSPaul E. McKenney */ 4274102adabSPaul E. McKenney struct rcu_state { 4284102adabSPaul E. McKenney struct rcu_node node[NUM_RCU_NODES]; /* Hierarchy. */ 4294102adabSPaul E. McKenney struct rcu_node *level[RCU_NUM_LVLS]; /* Hierarchy levels. */ 4304102adabSPaul E. McKenney u32 levelcnt[MAX_RCU_LVLS + 1]; /* # nodes in each level. */ 4314102adabSPaul E. McKenney u8 levelspread[RCU_NUM_LVLS]; /* kids/node in each level. */ 4324a81e832SPaul E. McKenney u8 flavor_mask; /* bit in flavor mask. */ 4334102adabSPaul E. McKenney struct rcu_data __percpu *rda; /* pointer of percu rcu_data. */ 4344102adabSPaul E. McKenney void (*call)(struct rcu_head *head, /* call_rcu() flavor. */ 4354102adabSPaul E. McKenney void (*func)(struct rcu_head *head)); 4364102adabSPaul E. McKenney 4374102adabSPaul E. McKenney /* The following fields are guarded by the root rcu_node's lock. */ 4384102adabSPaul E. McKenney 4394102adabSPaul E. McKenney u8 fqs_state ____cacheline_internodealigned_in_smp; 4404102adabSPaul E. McKenney /* Force QS state. */ 4414102adabSPaul E. McKenney u8 boost; /* Subject to priority boost. */ 4424102adabSPaul E. McKenney unsigned long gpnum; /* Current gp number. */ 4434102adabSPaul E. McKenney unsigned long completed; /* # of last completed gp. */ 4444102adabSPaul E. McKenney struct task_struct *gp_kthread; /* Task for grace periods. */ 4454102adabSPaul E. McKenney wait_queue_head_t gp_wq; /* Where GP task waits. */ 446afea227fSPaul E. McKenney short gp_flags; /* Commands for GP task. */ 447afea227fSPaul E. McKenney short gp_state; /* GP kthread sleep state. */ 4484102adabSPaul E. McKenney 4494102adabSPaul E. McKenney /* End of fields guarded by root rcu_node's lock. */ 4504102adabSPaul E. McKenney 4514102adabSPaul E. McKenney raw_spinlock_t orphan_lock ____cacheline_internodealigned_in_smp; 4524102adabSPaul E. McKenney /* Protect following fields. */ 4534102adabSPaul E. McKenney struct rcu_head *orphan_nxtlist; /* Orphaned callbacks that */ 4544102adabSPaul E. McKenney /* need a grace period. */ 4554102adabSPaul E. McKenney struct rcu_head **orphan_nxttail; /* Tail of above. */ 4564102adabSPaul E. McKenney struct rcu_head *orphan_donelist; /* Orphaned callbacks that */ 4574102adabSPaul E. McKenney /* are ready to invoke. */ 4584102adabSPaul E. McKenney struct rcu_head **orphan_donetail; /* Tail of above. */ 4594102adabSPaul E. McKenney long qlen_lazy; /* Number of lazy callbacks. */ 4604102adabSPaul E. McKenney long qlen; /* Total number of callbacks. */ 4614102adabSPaul E. McKenney /* End of fields guarded by orphan_lock. */ 4624102adabSPaul E. McKenney 4634102adabSPaul E. McKenney struct mutex onoff_mutex; /* Coordinate hotplug & GPs. */ 4644102adabSPaul E. McKenney 4654102adabSPaul E. McKenney struct mutex barrier_mutex; /* Guards barrier fields. */ 4664102adabSPaul E. McKenney atomic_t barrier_cpu_count; /* # CPUs waiting on. */ 4674102adabSPaul E. McKenney struct completion barrier_completion; /* Wake at barrier end. */ 4684102adabSPaul E. McKenney unsigned long n_barrier_done; /* ++ at start and end of */ 4694102adabSPaul E. McKenney /* _rcu_barrier(). */ 4704102adabSPaul E. McKenney /* End of fields guarded by barrier_mutex. */ 4714102adabSPaul E. McKenney 4724102adabSPaul E. McKenney atomic_long_t expedited_start; /* Starting ticket. */ 4734102adabSPaul E. McKenney atomic_long_t expedited_done; /* Done ticket. */ 4744102adabSPaul E. McKenney atomic_long_t expedited_wrap; /* # near-wrap incidents. */ 4754102adabSPaul E. McKenney atomic_long_t expedited_tryfail; /* # acquisition failures. */ 4764102adabSPaul E. McKenney atomic_long_t expedited_workdone1; /* # done by others #1. */ 4774102adabSPaul E. McKenney atomic_long_t expedited_workdone2; /* # done by others #2. */ 4784102adabSPaul E. McKenney atomic_long_t expedited_normal; /* # fallbacks to normal. */ 4794102adabSPaul E. McKenney atomic_long_t expedited_stoppedcpus; /* # successful stop_cpus. */ 4804102adabSPaul E. McKenney atomic_long_t expedited_done_tries; /* # tries to update _done. */ 4814102adabSPaul E. McKenney atomic_long_t expedited_done_lost; /* # times beaten to _done. */ 4824102adabSPaul E. McKenney atomic_long_t expedited_done_exit; /* # times exited _done loop. */ 4834102adabSPaul E. McKenney 4844102adabSPaul E. McKenney unsigned long jiffies_force_qs; /* Time at which to invoke */ 4854102adabSPaul E. McKenney /* force_quiescent_state(). */ 4864102adabSPaul E. McKenney unsigned long n_force_qs; /* Number of calls to */ 4874102adabSPaul E. McKenney /* force_quiescent_state(). */ 4884102adabSPaul E. McKenney unsigned long n_force_qs_lh; /* ~Number of calls leaving */ 4894102adabSPaul E. McKenney /* due to lock unavailable. */ 4904102adabSPaul E. McKenney unsigned long n_force_qs_ngp; /* Number of calls leaving */ 4914102adabSPaul E. McKenney /* due to no GP active. */ 4924102adabSPaul E. McKenney unsigned long gp_start; /* Time at which GP started, */ 4934102adabSPaul E. McKenney /* but in jiffies. */ 4946ccd2ecdSPaul E. McKenney unsigned long gp_activity; /* Time of last GP kthread */ 4956ccd2ecdSPaul E. McKenney /* activity in jiffies. */ 4964102adabSPaul E. McKenney unsigned long jiffies_stall; /* Time at which to check */ 4974102adabSPaul E. McKenney /* for CPU stalls. */ 4986193c76aSPaul E. McKenney unsigned long jiffies_resched; /* Time at which to resched */ 4996193c76aSPaul E. McKenney /* a reluctant CPU. */ 500fc908ed3SPaul E. McKenney unsigned long n_force_qs_gpstart; /* Snapshot of n_force_qs at */ 501fc908ed3SPaul E. McKenney /* GP start. */ 5024102adabSPaul E. McKenney unsigned long gp_max; /* Maximum GP duration in */ 5034102adabSPaul E. McKenney /* jiffies. */ 5044102adabSPaul E. McKenney const char *name; /* Name of structure. */ 5054102adabSPaul E. McKenney char abbr; /* Abbreviated name. */ 5064102adabSPaul E. McKenney struct list_head flavors; /* List of RCU flavors. */ 5074102adabSPaul E. McKenney }; 5084102adabSPaul E. McKenney 5094102adabSPaul E. McKenney /* Values for rcu_state structure's gp_flags field. */ 5104102adabSPaul E. McKenney #define RCU_GP_FLAG_INIT 0x1 /* Need grace-period initialization. */ 5114102adabSPaul E. McKenney #define RCU_GP_FLAG_FQS 0x2 /* Need grace-period quiescent-state forcing. */ 5124102adabSPaul E. McKenney 513afea227fSPaul E. McKenney /* Values for rcu_state structure's gp_flags field. */ 514afea227fSPaul E. McKenney #define RCU_GP_WAIT_INIT 0 /* Initial state. */ 515afea227fSPaul E. McKenney #define RCU_GP_WAIT_GPS 1 /* Wait for grace-period start. */ 516afea227fSPaul E. McKenney #define RCU_GP_WAIT_FQS 2 /* Wait for force-quiescent-state time. */ 517afea227fSPaul E. McKenney 5184102adabSPaul E. McKenney extern struct list_head rcu_struct_flavors; 5194102adabSPaul E. McKenney 5204102adabSPaul E. McKenney /* Sequence through rcu_state structures for each RCU flavor. */ 5214102adabSPaul E. McKenney #define for_each_rcu_flavor(rsp) \ 5224102adabSPaul E. McKenney list_for_each_entry((rsp), &rcu_struct_flavors, flavors) 5234102adabSPaul E. McKenney 5244102adabSPaul E. McKenney /* Return values for rcu_preempt_offline_tasks(). */ 5254102adabSPaul E. McKenney 5264102adabSPaul E. McKenney #define RCU_OFL_TASKS_NORM_GP 0x1 /* Tasks blocking normal */ 5274102adabSPaul E. McKenney /* GP were moved to root. */ 5284102adabSPaul E. McKenney #define RCU_OFL_TASKS_EXP_GP 0x2 /* Tasks blocking expedited */ 5294102adabSPaul E. McKenney /* GP were moved to root. */ 5304102adabSPaul E. McKenney 5314102adabSPaul E. McKenney /* 5324102adabSPaul E. McKenney * RCU implementation internal declarations: 5334102adabSPaul E. McKenney */ 5344102adabSPaul E. McKenney extern struct rcu_state rcu_sched_state; 5354102adabSPaul E. McKenney DECLARE_PER_CPU(struct rcu_data, rcu_sched_data); 5364102adabSPaul E. McKenney 5374102adabSPaul E. McKenney extern struct rcu_state rcu_bh_state; 5384102adabSPaul E. McKenney DECLARE_PER_CPU(struct rcu_data, rcu_bh_data); 5394102adabSPaul E. McKenney 54028f6569aSPranith Kumar #ifdef CONFIG_PREEMPT_RCU 5414102adabSPaul E. McKenney extern struct rcu_state rcu_preempt_state; 5424102adabSPaul E. McKenney DECLARE_PER_CPU(struct rcu_data, rcu_preempt_data); 54328f6569aSPranith Kumar #endif /* #ifdef CONFIG_PREEMPT_RCU */ 5444102adabSPaul E. McKenney 5454102adabSPaul E. McKenney #ifdef CONFIG_RCU_BOOST 5464102adabSPaul E. McKenney DECLARE_PER_CPU(unsigned int, rcu_cpu_kthread_status); 5474102adabSPaul E. McKenney DECLARE_PER_CPU(int, rcu_cpu_kthread_cpu); 5484102adabSPaul E. McKenney DECLARE_PER_CPU(unsigned int, rcu_cpu_kthread_loops); 5494102adabSPaul E. McKenney DECLARE_PER_CPU(char, rcu_cpu_has_work); 5504102adabSPaul E. McKenney #endif /* #ifdef CONFIG_RCU_BOOST */ 5514102adabSPaul E. McKenney 5524102adabSPaul E. McKenney #ifndef RCU_TREE_NONCORE 5534102adabSPaul E. McKenney 5544102adabSPaul E. McKenney /* Forward declarations for rcutree_plugin.h */ 5554102adabSPaul E. McKenney static void rcu_bootup_announce(void); 5564102adabSPaul E. McKenney long rcu_batches_completed(void); 55738200cf2SPaul E. McKenney static void rcu_preempt_note_context_switch(void); 5584102adabSPaul E. McKenney static int rcu_preempt_blocked_readers_cgp(struct rcu_node *rnp); 5594102adabSPaul E. McKenney #ifdef CONFIG_HOTPLUG_CPU 5604102adabSPaul E. McKenney static void rcu_report_unblock_qs_rnp(struct rcu_node *rnp, 5614102adabSPaul E. McKenney unsigned long flags); 5624102adabSPaul E. McKenney #endif /* #ifdef CONFIG_HOTPLUG_CPU */ 5634102adabSPaul E. McKenney static void rcu_print_detail_task_stall(struct rcu_state *rsp); 5644102adabSPaul E. McKenney static int rcu_print_task_stall(struct rcu_node *rnp); 5654102adabSPaul E. McKenney static void rcu_preempt_check_blocked_tasks(struct rcu_node *rnp); 5664102adabSPaul E. McKenney #ifdef CONFIG_HOTPLUG_CPU 5674102adabSPaul E. McKenney static int rcu_preempt_offline_tasks(struct rcu_state *rsp, 5684102adabSPaul E. McKenney struct rcu_node *rnp, 5694102adabSPaul E. McKenney struct rcu_data *rdp); 5704102adabSPaul E. McKenney #endif /* #ifdef CONFIG_HOTPLUG_CPU */ 57186aea0e6SPaul E. McKenney static void rcu_preempt_check_callbacks(void); 5724102adabSPaul E. McKenney void call_rcu(struct rcu_head *head, void (*func)(struct rcu_head *rcu)); 57328f6569aSPranith Kumar #if defined(CONFIG_HOTPLUG_CPU) || defined(CONFIG_PREEMPT_RCU) 5744102adabSPaul E. McKenney static void rcu_report_exp_rnp(struct rcu_state *rsp, struct rcu_node *rnp, 5754102adabSPaul E. McKenney bool wake); 57628f6569aSPranith Kumar #endif /* #if defined(CONFIG_HOTPLUG_CPU) || defined(CONFIG_PREEMPT_RCU) */ 5774102adabSPaul E. McKenney static void __init __rcu_init_preempt(void); 5784102adabSPaul E. McKenney static void rcu_initiate_boost(struct rcu_node *rnp, unsigned long flags); 5794102adabSPaul E. McKenney static void rcu_preempt_boost_start_gp(struct rcu_node *rnp); 5804102adabSPaul E. McKenney static void invoke_rcu_callbacks_kthread(void); 5814102adabSPaul E. McKenney static bool rcu_is_callbacks_kthread(void); 5824102adabSPaul E. McKenney #ifdef CONFIG_RCU_BOOST 5834102adabSPaul E. McKenney static void rcu_preempt_do_callbacks(void); 5844102adabSPaul E. McKenney static int rcu_spawn_one_boost_kthread(struct rcu_state *rsp, 5854102adabSPaul E. McKenney struct rcu_node *rnp); 5864102adabSPaul E. McKenney #endif /* #ifdef CONFIG_RCU_BOOST */ 5879386c0b7SPaul E. McKenney static void __init rcu_spawn_boost_kthreads(void); 5884102adabSPaul E. McKenney static void rcu_prepare_kthreads(int cpu); 5898fa7845dSPaul E. McKenney static void rcu_cleanup_after_idle(void); 590198bbf81SPaul E. McKenney static void rcu_prepare_for_idle(void); 5914102adabSPaul E. McKenney static void rcu_idle_count_callbacks_posted(void); 5924102adabSPaul E. McKenney static void print_cpu_stall_info_begin(void); 5934102adabSPaul E. McKenney static void print_cpu_stall_info(struct rcu_state *rsp, int cpu); 5944102adabSPaul E. McKenney static void print_cpu_stall_info_end(void); 5954102adabSPaul E. McKenney static void zero_cpu_stall_ticks(struct rcu_data *rdp); 5964102adabSPaul E. McKenney static void increment_cpu_stall_ticks(void); 597d7e29933SPaul E. McKenney static bool rcu_nocb_cpu_needs_barrier(struct rcu_state *rsp, int cpu); 5984102adabSPaul E. McKenney static void rcu_nocb_gp_set(struct rcu_node *rnp, int nrq); 5994102adabSPaul E. McKenney static void rcu_nocb_gp_cleanup(struct rcu_state *rsp, struct rcu_node *rnp); 6004102adabSPaul E. McKenney static void rcu_init_one_nocb(struct rcu_node *rnp); 6014102adabSPaul E. McKenney static bool __call_rcu_nocb(struct rcu_data *rdp, struct rcu_head *rhp, 60296d3fd0dSPaul E. McKenney bool lazy, unsigned long flags); 6034102adabSPaul E. McKenney static bool rcu_nocb_adopt_orphan_cbs(struct rcu_state *rsp, 60496d3fd0dSPaul E. McKenney struct rcu_data *rdp, 60596d3fd0dSPaul E. McKenney unsigned long flags); 6069fdd3bc9SPaul E. McKenney static int rcu_nocb_need_deferred_wakeup(struct rcu_data *rdp); 60796d3fd0dSPaul E. McKenney static void do_nocb_deferred_wakeup(struct rcu_data *rdp); 6084102adabSPaul E. McKenney static void rcu_boot_init_nocb_percpu_data(struct rcu_data *rdp); 60935ce7f29SPaul E. McKenney static void rcu_spawn_all_nocb_kthreads(int cpu); 61035ce7f29SPaul E. McKenney static void __init rcu_spawn_nocb_kthreads(void); 61135ce7f29SPaul E. McKenney #ifdef CONFIG_RCU_NOCB_CPU 61235ce7f29SPaul E. McKenney static void __init rcu_organize_nocb_kthreads(struct rcu_state *rsp); 61335ce7f29SPaul E. McKenney #endif /* #ifdef CONFIG_RCU_NOCB_CPU */ 6144a81e832SPaul E. McKenney static void __maybe_unused rcu_kick_nohz_cpu(int cpu); 6154102adabSPaul E. McKenney static bool init_nocb_callback_list(struct rcu_data *rdp); 61628ced795SChristoph Lameter static void rcu_sysidle_enter(int irq); 61728ced795SChristoph Lameter static void rcu_sysidle_exit(int irq); 6184102adabSPaul E. McKenney static void rcu_sysidle_check_cpu(struct rcu_data *rdp, bool *isidle, 6194102adabSPaul E. McKenney unsigned long *maxj); 6204102adabSPaul E. McKenney static bool is_sysidle_rcu_state(struct rcu_state *rsp); 6214102adabSPaul E. McKenney static void rcu_sysidle_report_gp(struct rcu_state *rsp, int isidle, 6224102adabSPaul E. McKenney unsigned long maxj); 6234102adabSPaul E. McKenney static void rcu_bind_gp_kthread(void); 6244102adabSPaul E. McKenney static void rcu_sysidle_init_percpu_data(struct rcu_dynticks *rdtp); 625a096932fSPaul E. McKenney static bool rcu_nohz_full_cpu(struct rcu_state *rsp); 626176f8f7aSPaul E. McKenney static void rcu_dynticks_task_enter(void); 627176f8f7aSPaul E. McKenney static void rcu_dynticks_task_exit(void); 6284102adabSPaul E. McKenney 6294102adabSPaul E. McKenney #endif /* #ifndef RCU_TREE_NONCORE */ 6304102adabSPaul E. McKenney 6314102adabSPaul E. McKenney #ifdef CONFIG_RCU_TRACE 6324102adabSPaul E. McKenney #ifdef CONFIG_RCU_NOCB_CPU 6334102adabSPaul E. McKenney /* Sum up queue lengths for tracing. */ 6344102adabSPaul E. McKenney static inline void rcu_nocb_q_lengths(struct rcu_data *rdp, long *ql, long *qll) 6354102adabSPaul E. McKenney { 636fbce7497SPaul E. McKenney *ql = atomic_long_read(&rdp->nocb_q_count) + 637fbce7497SPaul E. McKenney rdp->nocb_p_count + 638fbce7497SPaul E. McKenney atomic_long_read(&rdp->nocb_follower_count) + 639fbce7497SPaul E. McKenney rdp->nocb_p_count + rdp->nocb_gp_count; 640fbce7497SPaul E. McKenney *qll = atomic_long_read(&rdp->nocb_q_count_lazy) + 641fbce7497SPaul E. McKenney rdp->nocb_p_count_lazy + 642fbce7497SPaul E. McKenney atomic_long_read(&rdp->nocb_follower_count_lazy) + 643fbce7497SPaul E. McKenney rdp->nocb_p_count_lazy + rdp->nocb_gp_count_lazy; 6444102adabSPaul E. McKenney } 6454102adabSPaul E. McKenney #else /* #ifdef CONFIG_RCU_NOCB_CPU */ 6464102adabSPaul E. McKenney static inline void rcu_nocb_q_lengths(struct rcu_data *rdp, long *ql, long *qll) 6474102adabSPaul E. McKenney { 6484102adabSPaul E. McKenney *ql = 0; 6494102adabSPaul E. McKenney *qll = 0; 6504102adabSPaul E. McKenney } 6514102adabSPaul E. McKenney #endif /* #else #ifdef CONFIG_RCU_NOCB_CPU */ 6524102adabSPaul E. McKenney #endif /* #ifdef CONFIG_RCU_TRACE */ 653