+++ /dev/null
-/*
- * Read-Copy Update mechanism for mutual exclusion (tree-based version)
- * Internal non-public definitions.
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
- *
- * Copyright IBM Corporation, 2008
- *
- * Author: Ingo Molnar <mingo@elte.hu>
- * Paul E. McKenney <paulmck@linux.vnet.ibm.com>
- */
-
-#include <linux/cache.h>
-#include <linux/spinlock.h>
-#include <linux/threads.h>
-#include <linux/cpumask.h>
-#include <linux/seqlock.h>
-#include <linux/irq_work.h>
-
-/*
- * Define shape of hierarchy based on NR_CPUS, CONFIG_RCU_FANOUT, and
- * CONFIG_RCU_FANOUT_LEAF.
- * In theory, it should be possible to add more levels straightforwardly.
- * In practice, this did work well going from three levels to four.
- * Of course, your mileage may vary.
- */
-#define MAX_RCU_LVLS 4
-#define RCU_FANOUT_1 (CONFIG_RCU_FANOUT_LEAF)
-#define RCU_FANOUT_2 (RCU_FANOUT_1 * CONFIG_RCU_FANOUT)
-#define RCU_FANOUT_3 (RCU_FANOUT_2 * CONFIG_RCU_FANOUT)
-#define RCU_FANOUT_4 (RCU_FANOUT_3 * CONFIG_RCU_FANOUT)
-
-#if NR_CPUS <= RCU_FANOUT_1
-# define RCU_NUM_LVLS 1
-# define NUM_RCU_LVL_0 1
-# define NUM_RCU_LVL_1 (NR_CPUS)
-# define NUM_RCU_LVL_2 0
-# define NUM_RCU_LVL_3 0
-# define NUM_RCU_LVL_4 0
-#elif NR_CPUS <= RCU_FANOUT_2
-# define RCU_NUM_LVLS 2
-# define NUM_RCU_LVL_0 1
-# define NUM_RCU_LVL_1 DIV_ROUND_UP(NR_CPUS, RCU_FANOUT_1)
-# define NUM_RCU_LVL_2 (NR_CPUS)
-# define NUM_RCU_LVL_3 0
-# define NUM_RCU_LVL_4 0
-#elif NR_CPUS <= RCU_FANOUT_3
-# define RCU_NUM_LVLS 3
-# define NUM_RCU_LVL_0 1
-# define NUM_RCU_LVL_1 DIV_ROUND_UP(NR_CPUS, RCU_FANOUT_2)
-# define NUM_RCU_LVL_2 DIV_ROUND_UP(NR_CPUS, RCU_FANOUT_1)
-# define NUM_RCU_LVL_3 (NR_CPUS)
-# define NUM_RCU_LVL_4 0
-#elif NR_CPUS <= RCU_FANOUT_4
-# define RCU_NUM_LVLS 4
-# define NUM_RCU_LVL_0 1
-# define NUM_RCU_LVL_1 DIV_ROUND_UP(NR_CPUS, RCU_FANOUT_3)
-# define NUM_RCU_LVL_2 DIV_ROUND_UP(NR_CPUS, RCU_FANOUT_2)
-# define NUM_RCU_LVL_3 DIV_ROUND_UP(NR_CPUS, RCU_FANOUT_1)
-# define NUM_RCU_LVL_4 (NR_CPUS)
-#else
-# error "CONFIG_RCU_FANOUT insufficient for NR_CPUS"
-#endif /* #if (NR_CPUS) <= RCU_FANOUT_1 */
-
-#define RCU_SUM (NUM_RCU_LVL_0 + NUM_RCU_LVL_1 + NUM_RCU_LVL_2 + NUM_RCU_LVL_3 + NUM_RCU_LVL_4)
-#define NUM_RCU_NODES (RCU_SUM - NR_CPUS)
-
-extern int rcu_num_lvls;
-extern int rcu_num_nodes;
-
-/*
- * Dynticks per-CPU state.
- */
-struct rcu_dynticks {
- long long dynticks_nesting; /* Track irq/process nesting level. */
- /* Process level is worth LLONG_MAX/2. */
- int dynticks_nmi_nesting; /* Track NMI nesting level. */
- atomic_t dynticks; /* Even value for idle, else odd. */
-#ifdef CONFIG_NO_HZ_FULL_SYSIDLE
- long long dynticks_idle_nesting;
- /* irq/process nesting level from idle. */
- atomic_t dynticks_idle; /* Even value for idle, else odd. */
- /* "Idle" excludes userspace execution. */
- unsigned long dynticks_idle_jiffies;
- /* End of last non-NMI non-idle period. */
-#endif /* #ifdef CONFIG_NO_HZ_FULL_SYSIDLE */
-#ifdef CONFIG_RCU_FAST_NO_HZ
- bool all_lazy; /* Are all CPU's CBs lazy? */
- unsigned long nonlazy_posted;
- /* # times non-lazy CBs posted to CPU. */
- unsigned long nonlazy_posted_snap;
- /* idle-period nonlazy_posted snapshot. */
- unsigned long last_accelerate;
- /* Last jiffy CBs were accelerated. */
- unsigned long last_advance_all;
- /* Last jiffy CBs were all advanced. */
- int tick_nohz_enabled_snap; /* Previously seen value from sysfs. */
-#endif /* #ifdef CONFIG_RCU_FAST_NO_HZ */
-};
-
-/* RCU's kthread states for tracing. */
-#define RCU_KTHREAD_STOPPED 0
-#define RCU_KTHREAD_RUNNING 1
-#define RCU_KTHREAD_WAITING 2
-#define RCU_KTHREAD_OFFCPU 3
-#define RCU_KTHREAD_YIELDING 4
-#define RCU_KTHREAD_MAX 4
-
-/*
- * Definition for node within the RCU grace-period-detection hierarchy.
- */
-struct rcu_node {
- raw_spinlock_t lock; /* Root rcu_node's lock protects some */
- /* rcu_state fields as well as following. */
- unsigned long gpnum; /* Current grace period for this node. */
- /* This will either be equal to or one */
- /* behind the root rcu_node's gpnum. */
- unsigned long completed; /* Last GP completed for this node. */
- /* This will either be equal to or one */
- /* behind the root rcu_node's gpnum. */
- unsigned long qsmask; /* CPUs or groups that need to switch in */
- /* order for current grace period to proceed.*/
- /* In leaf rcu_node, each bit corresponds to */
- /* an rcu_data structure, otherwise, each */
- /* bit corresponds to a child rcu_node */
- /* structure. */
- unsigned long expmask; /* Groups that have ->blkd_tasks */
- /* elements that need to drain to allow the */
- /* current expedited grace period to */
- /* complete (only for TREE_PREEMPT_RCU). */
- unsigned long qsmaskinit;
- /* Per-GP initial value for qsmask & expmask. */
- unsigned long grpmask; /* Mask to apply to parent qsmask. */
- /* Only one bit will be set in this mask. */
- int grplo; /* lowest-numbered CPU or group here. */
- int grphi; /* highest-numbered CPU or group here. */
- u8 grpnum; /* CPU/group number for next level up. */
- u8 level; /* root is at level 0. */
- struct rcu_node *parent;
- struct list_head blkd_tasks;
- /* Tasks blocked in RCU read-side critical */
- /* section. Tasks are placed at the head */
- /* of this list and age towards the tail. */
- struct list_head *gp_tasks;
- /* Pointer to the first task blocking the */
- /* current grace period, or NULL if there */
- /* is no such task. */
- struct list_head *exp_tasks;
- /* Pointer to the first task blocking the */
- /* current expedited grace period, or NULL */
- /* if there is no such task. If there */
- /* is no current expedited grace period, */
- /* then there can cannot be any such task. */
-#ifdef CONFIG_RCU_BOOST
- struct list_head *boost_tasks;
- /* Pointer to first task that needs to be */
- /* priority boosted, or NULL if no priority */
- /* boosting is needed for this rcu_node */
- /* structure. If there are no tasks */
- /* queued on this rcu_node structure that */
- /* are blocking the current grace period, */
- /* there can be no such task. */
- unsigned long boost_time;
- /* When to start boosting (jiffies). */
- struct task_struct *boost_kthread_task;
- /* kthread that takes care of priority */
- /* boosting for this rcu_node structure. */
- unsigned int boost_kthread_status;
- /* State of boost_kthread_task for tracing. */
- unsigned long n_tasks_boosted;
- /* Total number of tasks boosted. */
- unsigned long n_exp_boosts;
- /* Number of tasks boosted for expedited GP. */
- unsigned long n_normal_boosts;
- /* Number of tasks boosted for normal GP. */
- unsigned long n_balk_blkd_tasks;
- /* Refused to boost: no blocked tasks. */
- unsigned long n_balk_exp_gp_tasks;
- /* Refused to boost: nothing blocking GP. */
- unsigned long n_balk_boost_tasks;
- /* Refused to boost: already boosting. */
- unsigned long n_balk_notblocked;
- /* Refused to boost: RCU RS CS still running. */
- unsigned long n_balk_notyet;
- /* Refused to boost: not yet time. */
- unsigned long n_balk_nos;
- /* Refused to boost: not sure why, though. */
- /* This can happen due to race conditions. */
-#endif /* #ifdef CONFIG_RCU_BOOST */
-#ifdef CONFIG_RCU_NOCB_CPU
- wait_queue_head_t nocb_gp_wq[2];
- /* Place for rcu_nocb_kthread() to wait GP. */
-#endif /* #ifdef CONFIG_RCU_NOCB_CPU */
- int need_future_gp[2];
- /* Counts of upcoming no-CB GP requests. */
- raw_spinlock_t fqslock ____cacheline_internodealigned_in_smp;
-} ____cacheline_internodealigned_in_smp;
-
-/*
- * Do a full breadth-first scan of the rcu_node structures for the
- * specified rcu_state structure.
- */
-#define rcu_for_each_node_breadth_first(rsp, rnp) \
- for ((rnp) = &(rsp)->node[0]; \
- (rnp) < &(rsp)->node[rcu_num_nodes]; (rnp)++)
-
-/*
- * Do a breadth-first scan of the non-leaf rcu_node structures for the
- * specified rcu_state structure. Note that if there is a singleton
- * rcu_node tree with but one rcu_node structure, this loop is a no-op.
- */
-#define rcu_for_each_nonleaf_node_breadth_first(rsp, rnp) \
- for ((rnp) = &(rsp)->node[0]; \
- (rnp) < (rsp)->level[rcu_num_lvls - 1]; (rnp)++)
-
-/*
- * Scan the leaves of the rcu_node hierarchy for the specified rcu_state
- * structure. Note that if there is a singleton rcu_node tree with but
- * one rcu_node structure, this loop -will- visit the rcu_node structure.
- * It is still a leaf node, even if it is also the root node.
- */
-#define rcu_for_each_leaf_node(rsp, rnp) \
- for ((rnp) = (rsp)->level[rcu_num_lvls - 1]; \
- (rnp) < &(rsp)->node[rcu_num_nodes]; (rnp)++)
-
-/* Index values for nxttail array in struct rcu_data. */
-#define RCU_DONE_TAIL 0 /* Also RCU_WAIT head. */
-#define RCU_WAIT_TAIL 1 /* Also RCU_NEXT_READY head. */
-#define RCU_NEXT_READY_TAIL 2 /* Also RCU_NEXT head. */
-#define RCU_NEXT_TAIL 3
-#define RCU_NEXT_SIZE 4
-
-/* Per-CPU data for read-copy update. */
-struct rcu_data {
- /* 1) quiescent-state and grace-period handling : */
- unsigned long completed; /* Track rsp->completed gp number */
- /* in order to detect GP end. */
- unsigned long gpnum; /* Highest gp number that this CPU */
- /* is aware of having started. */
- bool passed_quiesce; /* User-mode/idle loop etc. */
- bool qs_pending; /* Core waits for quiesc state. */
- bool beenonline; /* CPU online at least once. */
- bool preemptible; /* Preemptible RCU? */
- struct rcu_node *mynode; /* This CPU's leaf of hierarchy */
- unsigned long grpmask; /* Mask to apply to leaf qsmask. */
-#ifdef CONFIG_RCU_CPU_STALL_INFO
- unsigned long ticks_this_gp; /* The number of scheduling-clock */
- /* ticks this CPU has handled */
- /* during and after the last grace */
- /* period it is aware of. */
-#endif /* #ifdef CONFIG_RCU_CPU_STALL_INFO */
-
- /* 2) batch handling */
- /*
- * If nxtlist is not NULL, it is partitioned as follows.
- * Any of the partitions might be empty, in which case the
- * pointer to that partition will be equal to the pointer for
- * the following partition. When the list is empty, all of
- * the nxttail elements point to the ->nxtlist pointer itself,
- * which in that case is NULL.
- *
- * [nxtlist, *nxttail[RCU_DONE_TAIL]):
- * Entries that batch # <= ->completed
- * The grace period for these entries has completed, and
- * the other grace-period-completed entries may be moved
- * here temporarily in rcu_process_callbacks().
- * [*nxttail[RCU_DONE_TAIL], *nxttail[RCU_WAIT_TAIL]):
- * Entries that batch # <= ->completed - 1: waiting for current GP
- * [*nxttail[RCU_WAIT_TAIL], *nxttail[RCU_NEXT_READY_TAIL]):
- * Entries known to have arrived before current GP ended
- * [*nxttail[RCU_NEXT_READY_TAIL], *nxttail[RCU_NEXT_TAIL]):
- * Entries that might have arrived after current GP ended
- * Note that the value of *nxttail[RCU_NEXT_TAIL] will
- * always be NULL, as this is the end of the list.
- */
- struct rcu_head *nxtlist;
- struct rcu_head **nxttail[RCU_NEXT_SIZE];
- unsigned long nxtcompleted[RCU_NEXT_SIZE];
- /* grace periods for sublists. */
- long qlen_lazy; /* # of lazy queued callbacks */
- long qlen; /* # of queued callbacks, incl lazy */
- long qlen_last_fqs_check;
- /* qlen at last check for QS forcing */
- unsigned long n_cbs_invoked; /* count of RCU cbs invoked. */
- unsigned long n_nocbs_invoked; /* count of no-CBs RCU cbs invoked. */
- unsigned long n_cbs_orphaned; /* RCU cbs orphaned by dying CPU */
- unsigned long n_cbs_adopted; /* RCU cbs adopted from dying CPU */
- unsigned long n_force_qs_snap;
- /* did other CPU force QS recently? */
- long blimit; /* Upper limit on a processed batch */
-
- /* 3) dynticks interface. */
- struct rcu_dynticks *dynticks; /* Shared per-CPU dynticks state. */
- int dynticks_snap; /* Per-GP tracking for dynticks. */
-
- /* 4) reasons this CPU needed to be kicked by force_quiescent_state */
- unsigned long dynticks_fqs; /* Kicked due to dynticks idle. */
- unsigned long offline_fqs; /* Kicked due to being offline. */
-
- /* 5) __rcu_pending() statistics. */
- unsigned long n_rcu_pending; /* rcu_pending() calls since boot. */
- unsigned long n_rp_qs_pending;
- unsigned long n_rp_report_qs;
- unsigned long n_rp_cb_ready;
- unsigned long n_rp_cpu_needs_gp;
- unsigned long n_rp_gp_completed;
- unsigned long n_rp_gp_started;
- unsigned long n_rp_need_nothing;
-
- /* 6) _rcu_barrier() and OOM callbacks. */
- struct rcu_head barrier_head;
-#ifdef CONFIG_RCU_FAST_NO_HZ
- struct rcu_head oom_head;
-#endif /* #ifdef CONFIG_RCU_FAST_NO_HZ */
-
- /* 7) Callback offloading. */
-#ifdef CONFIG_RCU_NOCB_CPU
- struct rcu_head *nocb_head; /* CBs waiting for kthread. */
- struct rcu_head **nocb_tail;
- atomic_long_t nocb_q_count; /* # CBs waiting for kthread */
- atomic_long_t nocb_q_count_lazy; /* (approximate). */
- int nocb_p_count; /* # CBs being invoked by kthread */
- int nocb_p_count_lazy; /* (approximate). */
- wait_queue_head_t nocb_wq; /* For nocb kthreads to sleep on. */
- struct task_struct *nocb_kthread;
-#endif /* #ifdef CONFIG_RCU_NOCB_CPU */
-
- /* 8) RCU CPU stall data. */
-#ifdef CONFIG_RCU_CPU_STALL_INFO
- unsigned int softirq_snap; /* Snapshot of softirq activity. */
-#endif /* #ifdef CONFIG_RCU_CPU_STALL_INFO */
-
- int cpu;
- struct rcu_state *rsp;
-};
-
-/* Values for fqs_state field in struct rcu_state. */
-#define RCU_GP_IDLE 0 /* No grace period in progress. */
-#define RCU_GP_INIT 1 /* Grace period being initialized. */
-#define RCU_SAVE_DYNTICK 2 /* Need to scan dyntick state. */
-#define RCU_FORCE_QS 3 /* Need to force quiescent state. */
-#define RCU_SIGNAL_INIT RCU_SAVE_DYNTICK
-
-#define RCU_JIFFIES_TILL_FORCE_QS (1 + (HZ > 250) + (HZ > 500))
- /* For jiffies_till_first_fqs and */
- /* and jiffies_till_next_fqs. */
-
-#define RCU_JIFFIES_FQS_DIV 256 /* Very large systems need more */
- /* delay between bouts of */
- /* quiescent-state forcing. */
-
-#define RCU_STALL_RAT_DELAY 2 /* Allow other CPUs time to take */
- /* at least one scheduling clock */
- /* irq before ratting on them. */
-
-#define rcu_wait(cond) \
-do { \
- for (;;) { \
- set_current_state(TASK_INTERRUPTIBLE); \
- if (cond) \
- break; \
- schedule(); \
- } \
- __set_current_state(TASK_RUNNING); \
-} while (0)
-
-/*
- * RCU global state, including node hierarchy. This hierarchy is
- * represented in "heap" form in a dense array. The root (first level)
- * of the hierarchy is in ->node[0] (referenced by ->level[0]), the second
- * level in ->node[1] through ->node[m] (->node[1] referenced by ->level[1]),
- * and the third level in ->node[m+1] and following (->node[m+1] referenced
- * by ->level[2]). The number of levels is determined by the number of
- * CPUs and by CONFIG_RCU_FANOUT. Small systems will have a "hierarchy"
- * consisting of a single rcu_node.
- */
-struct rcu_state {
- struct rcu_node node[NUM_RCU_NODES]; /* Hierarchy. */
- struct rcu_node *level[RCU_NUM_LVLS]; /* Hierarchy levels. */
- u32 levelcnt[MAX_RCU_LVLS + 1]; /* # nodes in each level. */
- u8 levelspread[RCU_NUM_LVLS]; /* kids/node in each level. */
- struct rcu_data __percpu *rda; /* pointer of percu rcu_data. */
- void (*call)(struct rcu_head *head, /* call_rcu() flavor. */
- void (*func)(struct rcu_head *head));
-
- /* The following fields are guarded by the root rcu_node's lock. */
-
- u8 fqs_state ____cacheline_internodealigned_in_smp;
- /* Force QS state. */
- u8 boost; /* Subject to priority boost. */
- unsigned long gpnum; /* Current gp number. */
- unsigned long completed; /* # of last completed gp. */
- struct task_struct *gp_kthread; /* Task for grace periods. */
- wait_queue_head_t gp_wq; /* Where GP task waits. */
- int gp_flags; /* Commands for GP task. */
-
- /* End of fields guarded by root rcu_node's lock. */
-
- raw_spinlock_t orphan_lock ____cacheline_internodealigned_in_smp;
- /* Protect following fields. */
- struct rcu_head *orphan_nxtlist; /* Orphaned callbacks that */
- /* need a grace period. */
- struct rcu_head **orphan_nxttail; /* Tail of above. */
- struct rcu_head *orphan_donelist; /* Orphaned callbacks that */
- /* are ready to invoke. */
- struct rcu_head **orphan_donetail; /* Tail of above. */
- long qlen_lazy; /* Number of lazy callbacks. */
- long qlen; /* Total number of callbacks. */
- /* End of fields guarded by orphan_lock. */
-
- struct mutex onoff_mutex; /* Coordinate hotplug & GPs. */
-
- struct mutex barrier_mutex; /* Guards barrier fields. */
- atomic_t barrier_cpu_count; /* # CPUs waiting on. */
- struct completion barrier_completion; /* Wake at barrier end. */
- unsigned long n_barrier_done; /* ++ at start and end of */
- /* _rcu_barrier(). */
- /* End of fields guarded by barrier_mutex. */
-
- atomic_long_t expedited_start; /* Starting ticket. */
- atomic_long_t expedited_done; /* Done ticket. */
- atomic_long_t expedited_wrap; /* # near-wrap incidents. */
- atomic_long_t expedited_tryfail; /* # acquisition failures. */
- atomic_long_t expedited_workdone1; /* # done by others #1. */
- atomic_long_t expedited_workdone2; /* # done by others #2. */
- atomic_long_t expedited_normal; /* # fallbacks to normal. */
- atomic_long_t expedited_stoppedcpus; /* # successful stop_cpus. */
- atomic_long_t expedited_done_tries; /* # tries to update _done. */
- atomic_long_t expedited_done_lost; /* # times beaten to _done. */
- atomic_long_t expedited_done_exit; /* # times exited _done loop. */
-
- unsigned long jiffies_force_qs; /* Time at which to invoke */
- /* force_quiescent_state(). */
- unsigned long n_force_qs; /* Number of calls to */
- /* force_quiescent_state(). */
- unsigned long n_force_qs_lh; /* ~Number of calls leaving */
- /* due to lock unavailable. */
- unsigned long n_force_qs_ngp; /* Number of calls leaving */
- /* due to no GP active. */
- unsigned long gp_start; /* Time at which GP started, */
- /* but in jiffies. */
- unsigned long jiffies_stall; /* Time at which to check */
- /* for CPU stalls. */
- unsigned long gp_max; /* Maximum GP duration in */
- /* jiffies. */
- const char *name; /* Name of structure. */
- char abbr; /* Abbreviated name. */
- struct list_head flavors; /* List of RCU flavors. */
- struct irq_work wakeup_work; /* Postponed wakeups */
-};
-
-/* Values for rcu_state structure's gp_flags field. */
-#define RCU_GP_FLAG_INIT 0x1 /* Need grace-period initialization. */
-#define RCU_GP_FLAG_FQS 0x2 /* Need grace-period quiescent-state forcing. */
-
-extern struct list_head rcu_struct_flavors;
-
-/* Sequence through rcu_state structures for each RCU flavor. */
-#define for_each_rcu_flavor(rsp) \
- list_for_each_entry((rsp), &rcu_struct_flavors, flavors)
-
-/* Return values for rcu_preempt_offline_tasks(). */
-
-#define RCU_OFL_TASKS_NORM_GP 0x1 /* Tasks blocking normal */
- /* GP were moved to root. */
-#define RCU_OFL_TASKS_EXP_GP 0x2 /* Tasks blocking expedited */
- /* GP were moved to root. */
-
-/*
- * RCU implementation internal declarations:
- */
-extern struct rcu_state rcu_sched_state;
-DECLARE_PER_CPU(struct rcu_data, rcu_sched_data);
-
-extern struct rcu_state rcu_bh_state;
-DECLARE_PER_CPU(struct rcu_data, rcu_bh_data);
-
-#ifdef CONFIG_TREE_PREEMPT_RCU
-extern struct rcu_state rcu_preempt_state;
-DECLARE_PER_CPU(struct rcu_data, rcu_preempt_data);
-#endif /* #ifdef CONFIG_TREE_PREEMPT_RCU */
-
-#ifdef CONFIG_RCU_BOOST
-DECLARE_PER_CPU(unsigned int, rcu_cpu_kthread_status);
-DECLARE_PER_CPU(int, rcu_cpu_kthread_cpu);
-DECLARE_PER_CPU(unsigned int, rcu_cpu_kthread_loops);
-DECLARE_PER_CPU(char, rcu_cpu_has_work);
-#endif /* #ifdef CONFIG_RCU_BOOST */
-
-#ifndef RCU_TREE_NONCORE
-
-/* Forward declarations for rcutree_plugin.h */
-static void rcu_bootup_announce(void);
-long rcu_batches_completed(void);
-static void rcu_preempt_note_context_switch(int cpu);
-static int rcu_preempt_blocked_readers_cgp(struct rcu_node *rnp);
-#ifdef CONFIG_HOTPLUG_CPU
-static void rcu_report_unblock_qs_rnp(struct rcu_node *rnp,
- unsigned long flags);
-#endif /* #ifdef CONFIG_HOTPLUG_CPU */
-static void rcu_print_detail_task_stall(struct rcu_state *rsp);
-static int rcu_print_task_stall(struct rcu_node *rnp);
-static void rcu_preempt_check_blocked_tasks(struct rcu_node *rnp);
-#ifdef CONFIG_HOTPLUG_CPU
-static int rcu_preempt_offline_tasks(struct rcu_state *rsp,
- struct rcu_node *rnp,
- struct rcu_data *rdp);
-#endif /* #ifdef CONFIG_HOTPLUG_CPU */
-static void rcu_preempt_check_callbacks(int cpu);
-void call_rcu(struct rcu_head *head, void (*func)(struct rcu_head *rcu));
-#if defined(CONFIG_HOTPLUG_CPU) || defined(CONFIG_TREE_PREEMPT_RCU)
-static void rcu_report_exp_rnp(struct rcu_state *rsp, struct rcu_node *rnp,
- bool wake);
-#endif /* #if defined(CONFIG_HOTPLUG_CPU) || defined(CONFIG_TREE_PREEMPT_RCU) */
-static void __init __rcu_init_preempt(void);
-static void rcu_initiate_boost(struct rcu_node *rnp, unsigned long flags);
-static void rcu_preempt_boost_start_gp(struct rcu_node *rnp);
-static void invoke_rcu_callbacks_kthread(void);
-static bool rcu_is_callbacks_kthread(void);
-#ifdef CONFIG_RCU_BOOST
-static void rcu_preempt_do_callbacks(void);
-static int rcu_spawn_one_boost_kthread(struct rcu_state *rsp,
- struct rcu_node *rnp);
-#endif /* #ifdef CONFIG_RCU_BOOST */
-static void rcu_prepare_kthreads(int cpu);
-static void rcu_cleanup_after_idle(int cpu);
-static void rcu_prepare_for_idle(int cpu);
-static void rcu_idle_count_callbacks_posted(void);
-static void print_cpu_stall_info_begin(void);
-static void print_cpu_stall_info(struct rcu_state *rsp, int cpu);
-static void print_cpu_stall_info_end(void);
-static void zero_cpu_stall_ticks(struct rcu_data *rdp);
-static void increment_cpu_stall_ticks(void);
-static int rcu_nocb_needs_gp(struct rcu_state *rsp);
-static void rcu_nocb_gp_set(struct rcu_node *rnp, int nrq);
-static void rcu_nocb_gp_cleanup(struct rcu_state *rsp, struct rcu_node *rnp);
-static void rcu_init_one_nocb(struct rcu_node *rnp);
-static bool __call_rcu_nocb(struct rcu_data *rdp, struct rcu_head *rhp,
- bool lazy);
-static bool rcu_nocb_adopt_orphan_cbs(struct rcu_state *rsp,
- struct rcu_data *rdp);
-static void rcu_boot_init_nocb_percpu_data(struct rcu_data *rdp);
-static void rcu_spawn_nocb_kthreads(struct rcu_state *rsp);
-static void rcu_kick_nohz_cpu(int cpu);
-static bool init_nocb_callback_list(struct rcu_data *rdp);
-static void rcu_sysidle_enter(struct rcu_dynticks *rdtp, int irq);
-static void rcu_sysidle_exit(struct rcu_dynticks *rdtp, int irq);
-static void rcu_sysidle_check_cpu(struct rcu_data *rdp, bool *isidle,
- unsigned long *maxj);
-static bool is_sysidle_rcu_state(struct rcu_state *rsp);
-static void rcu_sysidle_report_gp(struct rcu_state *rsp, int isidle,
- unsigned long maxj);
-static void rcu_bind_gp_kthread(void);
-static void rcu_sysidle_init_percpu_data(struct rcu_dynticks *rdtp);
-
-#endif /* #ifndef RCU_TREE_NONCORE */
-
-#ifdef CONFIG_RCU_TRACE
-#ifdef CONFIG_RCU_NOCB_CPU
-/* Sum up queue lengths for tracing. */
-static inline void rcu_nocb_q_lengths(struct rcu_data *rdp, long *ql, long *qll)
-{
- *ql = atomic_long_read(&rdp->nocb_q_count) + rdp->nocb_p_count;
- *qll = atomic_long_read(&rdp->nocb_q_count_lazy) + rdp->nocb_p_count_lazy;
-}
-#else /* #ifdef CONFIG_RCU_NOCB_CPU */
-static inline void rcu_nocb_q_lengths(struct rcu_data *rdp, long *ql, long *qll)
-{
- *ql = 0;
- *qll = 0;
-}
-#endif /* #else #ifdef CONFIG_RCU_NOCB_CPU */
-#endif /* #ifdef CONFIG_RCU_TRACE */
projects / firefly-linux-kernel-4.4.55.git / blobdiff