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-rw-r--r--Documentation/kernel-parameters.txt9
-rw-r--r--include/linux/list.h5
-rw-r--r--include/linux/list_bl.h5
-rw-r--r--include/linux/list_nulls.h3
-rw-r--r--include/linux/rculist.h5
-rw-r--r--include/linux/rcupdate.h59
-rw-r--r--include/linux/rcutiny.h3
-rw-r--r--include/linux/rcutree.h2
-rw-r--r--include/linux/srcu.h5
-rw-r--r--kernel/exit.c2
-rw-r--r--kernel/rcu/rcutorture.c6
-rw-r--r--kernel/rcu/srcu.c4
-rw-r--r--kernel/rcu/tiny.c8
-rw-r--r--kernel/rcu/tree.c55
-rw-r--r--kernel/rcu/tree.h21
-rw-r--r--kernel/rcu/tree_plugin.h10
-rw-r--r--kernel/rcu/tree_trace.c2
-rw-r--r--kernel/rcu/update.c2
-rw-r--r--kernel/sched/core.c1
19 files changed, 111 insertions, 96 deletions
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 22a4b687ea5b..23ec96877311 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -3074,9 +3074,12 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
cache-to-cache transfer latencies.
rcutree.rcu_fanout_leaf= [KNL]
- Increase the number of CPUs assigned to each
- leaf rcu_node structure. Useful for very large
- systems.
+ Change the number of CPUs assigned to each
+ leaf rcu_node structure. Useful for very
+ large systems, which will choose the value 64,
+ and for NUMA systems with large remote-access
+ latencies, which will choose a value aligned
+ with the appropriate hardware boundaries.
rcutree.jiffies_till_sched_qs= [KNL]
Set required age in jiffies for a
diff --git a/include/linux/list.h b/include/linux/list.h
index 3e3e64a61002..993395a2e55c 100644
--- a/include/linux/list.h
+++ b/include/linux/list.h
@@ -87,7 +87,7 @@ static inline void list_add_tail(struct list_head *new, struct list_head *head)
static inline void __list_del(struct list_head * prev, struct list_head * next)
{
next->prev = prev;
- prev->next = next;
+ WRITE_ONCE(prev->next, next);
}
/**
@@ -615,7 +615,8 @@ static inline void __hlist_del(struct hlist_node *n)
{
struct hlist_node *next = n->next;
struct hlist_node **pprev = n->pprev;
- *pprev = next;
+
+ WRITE_ONCE(*pprev, next);
if (next)
next->pprev = pprev;
}
diff --git a/include/linux/list_bl.h b/include/linux/list_bl.h
index 2eb88556c5c5..8132214e8efd 100644
--- a/include/linux/list_bl.h
+++ b/include/linux/list_bl.h
@@ -93,9 +93,10 @@ static inline void __hlist_bl_del(struct hlist_bl_node *n)
LIST_BL_BUG_ON((unsigned long)n & LIST_BL_LOCKMASK);
/* pprev may be `first`, so be careful not to lose the lock bit */
- *pprev = (struct hlist_bl_node *)
+ WRITE_ONCE(*pprev,
+ (struct hlist_bl_node *)
((unsigned long)next |
- ((unsigned long)*pprev & LIST_BL_LOCKMASK));
+ ((unsigned long)*pprev & LIST_BL_LOCKMASK)));
if (next)
next->pprev = pprev;
}
diff --git a/include/linux/list_nulls.h b/include/linux/list_nulls.h
index f266661d2666..444d2b1313bd 100644
--- a/include/linux/list_nulls.h
+++ b/include/linux/list_nulls.h
@@ -76,7 +76,8 @@ static inline void __hlist_nulls_del(struct hlist_nulls_node *n)
{
struct hlist_nulls_node *next = n->next;
struct hlist_nulls_node **pprev = n->pprev;
- *pprev = next;
+
+ WRITE_ONCE(*pprev, next);
if (!is_a_nulls(next))
next->pprev = pprev;
}
diff --git a/include/linux/rculist.h b/include/linux/rculist.h
index 17c6b1f84a77..5ed540986019 100644
--- a/include/linux/rculist.h
+++ b/include/linux/rculist.h
@@ -247,10 +247,7 @@ static inline void list_splice_init_rcu(struct list_head *list,
* primitives such as list_add_rcu() as long as it's guarded by rcu_read_lock().
*/
#define list_entry_rcu(ptr, type, member) \
-({ \
- typeof(*ptr) __rcu *__ptr = (typeof(*ptr) __rcu __force *)ptr; \
- container_of((typeof(ptr))rcu_dereference_raw(__ptr), type, member); \
-})
+ container_of(lockless_dereference(ptr), type, member)
/**
* Where are list_empty_rcu() and list_first_entry_rcu()?
diff --git a/include/linux/rcupdate.h b/include/linux/rcupdate.h
index 581abf848566..a0189ba67fde 100644
--- a/include/linux/rcupdate.h
+++ b/include/linux/rcupdate.h
@@ -160,7 +160,7 @@ void do_trace_rcu_torture_read(const char *rcutorturename,
* more than one CPU).
*/
void call_rcu(struct rcu_head *head,
- void (*func)(struct rcu_head *head));
+ rcu_callback_t func);
#else /* #ifdef CONFIG_PREEMPT_RCU */
@@ -191,7 +191,7 @@ void call_rcu(struct rcu_head *head,
* memory ordering guarantees.
*/
void call_rcu_bh(struct rcu_head *head,
- void (*func)(struct rcu_head *head));
+ rcu_callback_t func);
/**
* call_rcu_sched() - Queue an RCU for invocation after sched grace period.
@@ -213,7 +213,7 @@ void call_rcu_bh(struct rcu_head *head,
* memory ordering guarantees.
*/
void call_rcu_sched(struct rcu_head *head,
- void (*func)(struct rcu_head *rcu));
+ rcu_callback_t func);
void synchronize_sched(void);
@@ -274,7 +274,7 @@ do { \
* See the description of call_rcu() for more detailed information on
* memory ordering guarantees.
*/
-void call_rcu_tasks(struct rcu_head *head, void (*func)(struct rcu_head *head));
+void call_rcu_tasks(struct rcu_head *head, rcu_callback_t func);
void synchronize_rcu_tasks(void);
void rcu_barrier_tasks(void);
@@ -297,12 +297,14 @@ void synchronize_rcu(void);
static inline void __rcu_read_lock(void)
{
- preempt_disable();
+ if (IS_ENABLED(CONFIG_PREEMPT_COUNT))
+ preempt_disable();
}
static inline void __rcu_read_unlock(void)
{
- preempt_enable();
+ if (IS_ENABLED(CONFIG_PREEMPT_COUNT))
+ preempt_enable();
}
static inline void synchronize_rcu(void)
@@ -535,29 +537,9 @@ static inline int rcu_read_lock_sched_held(void)
#endif /* #else #ifdef CONFIG_DEBUG_LOCK_ALLOC */
-/* Deprecate rcu_lockdep_assert(): Use RCU_LOCKDEP_WARN() instead. */
-static inline void __attribute((deprecated)) deprecate_rcu_lockdep_assert(void)
-{
-}
-
#ifdef CONFIG_PROVE_RCU
/**
- * rcu_lockdep_assert - emit lockdep splat if specified condition not met
- * @c: condition to check
- * @s: informative message
- */
-#define rcu_lockdep_assert(c, s) \
- do { \
- static bool __section(.data.unlikely) __warned; \
- deprecate_rcu_lockdep_assert(); \
- if (debug_lockdep_rcu_enabled() && !__warned && !(c)) { \
- __warned = true; \
- lockdep_rcu_suspicious(__FILE__, __LINE__, s); \
- } \
- } while (0)
-
-/**
* RCU_LOCKDEP_WARN - emit lockdep splat if specified condition is met
* @c: condition to check
* @s: informative message
@@ -594,7 +576,6 @@ static inline void rcu_preempt_sleep_check(void)
#else /* #ifdef CONFIG_PROVE_RCU */
-#define rcu_lockdep_assert(c, s) deprecate_rcu_lockdep_assert()
#define RCU_LOCKDEP_WARN(c, s) do { } while (0)
#define rcu_sleep_check() do { } while (0)
@@ -811,6 +792,28 @@ static inline void rcu_preempt_sleep_check(void)
#define rcu_dereference_sched(p) rcu_dereference_sched_check(p, 0)
/**
+ * rcu_pointer_handoff() - Hand off a pointer from RCU to other mechanism
+ * @p: The pointer to hand off
+ *
+ * This is simply an identity function, but it documents where a pointer
+ * is handed off from RCU to some other synchronization mechanism, for
+ * example, reference counting or locking. In C11, it would map to
+ * kill_dependency(). It could be used as follows:
+ *
+ * rcu_read_lock();
+ * p = rcu_dereference(gp);
+ * long_lived = is_long_lived(p);
+ * if (long_lived) {
+ * if (!atomic_inc_not_zero(p->refcnt))
+ * long_lived = false;
+ * else
+ * p = rcu_pointer_handoff(p);
+ * }
+ * rcu_read_unlock();
+ */
+#define rcu_pointer_handoff(p) (p)
+
+/**
* rcu_read_lock() - mark the beginning of an RCU read-side critical section
*
* When synchronize_rcu() is invoked on one CPU while other CPUs
@@ -1065,7 +1068,7 @@ static inline notrace void rcu_read_unlock_sched_notrace(void)
#define __kfree_rcu(head, offset) \
do { \
BUILD_BUG_ON(!__is_kfree_rcu_offset(offset)); \
- kfree_call_rcu(head, (void (*)(struct rcu_head *))(unsigned long)(offset)); \
+ kfree_call_rcu(head, (rcu_callback_t)(unsigned long)(offset)); \
} while (0)
/**
diff --git a/include/linux/rcutiny.h b/include/linux/rcutiny.h
index ff968b7af3a4..4c1aaf9cce7b 100644
--- a/include/linux/rcutiny.h
+++ b/include/linux/rcutiny.h
@@ -83,7 +83,7 @@ static inline void synchronize_sched_expedited(void)
}
static inline void kfree_call_rcu(struct rcu_head *head,
- void (*func)(struct rcu_head *rcu))
+ rcu_callback_t func)
{
call_rcu(head, func);
}
@@ -216,6 +216,7 @@ static inline bool rcu_is_watching(void)
static inline void rcu_all_qs(void)
{
+ barrier(); /* Avoid RCU read-side critical sections leaking across. */
}
#endif /* __LINUX_RCUTINY_H */
diff --git a/include/linux/rcutree.h b/include/linux/rcutree.h
index 5abec82f325e..60d15a080d7c 100644
--- a/include/linux/rcutree.h
+++ b/include/linux/rcutree.h
@@ -48,7 +48,7 @@ void synchronize_rcu_bh(void);
void synchronize_sched_expedited(void);
void synchronize_rcu_expedited(void);
-void kfree_call_rcu(struct rcu_head *head, void (*func)(struct rcu_head *rcu));
+void kfree_call_rcu(struct rcu_head *head, rcu_callback_t func);
/**
* synchronize_rcu_bh_expedited - Brute-force RCU-bh grace period
diff --git a/include/linux/srcu.h b/include/linux/srcu.h
index bdeb4567b71e..f5f80c5643ac 100644
--- a/include/linux/srcu.h
+++ b/include/linux/srcu.h
@@ -215,8 +215,11 @@ static inline int srcu_read_lock_held(struct srcu_struct *sp)
*/
static inline int srcu_read_lock(struct srcu_struct *sp) __acquires(sp)
{
- int retval = __srcu_read_lock(sp);
+ int retval;
+ preempt_disable();
+ retval = __srcu_read_lock(sp);
+ preempt_enable();
rcu_lock_acquire(&(sp)->dep_map);
return retval;
}
diff --git a/kernel/exit.c b/kernel/exit.c
index ea95ee1b5ef7..0e93b63bbc59 100644
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -761,7 +761,9 @@ void do_exit(long code)
*/
flush_ptrace_hw_breakpoint(tsk);
+ TASKS_RCU(preempt_disable());
TASKS_RCU(tasks_rcu_i = __srcu_read_lock(&tasks_rcu_exit_srcu));
+ TASKS_RCU(preempt_enable());
exit_notify(tsk, group_dead);
proc_exit_connector(tsk);
#ifdef CONFIG_NUMA
diff --git a/kernel/rcu/rcutorture.c b/kernel/rcu/rcutorture.c
index 77192953dee5..f9ec6cbe77d3 100644
--- a/kernel/rcu/rcutorture.c
+++ b/kernel/rcu/rcutorture.c
@@ -252,7 +252,7 @@ struct rcu_torture_ops {
void (*exp_sync)(void);
unsigned long (*get_state)(void);
void (*cond_sync)(unsigned long oldstate);
- void (*call)(struct rcu_head *head, void (*func)(struct rcu_head *rcu));
+ call_rcu_func_t call;
void (*cb_barrier)(void);
void (*fqs)(void);
void (*stats)(void);
@@ -448,7 +448,7 @@ static void synchronize_rcu_busted(void)
}
static void
-call_rcu_busted(struct rcu_head *head, void (*func)(struct rcu_head *rcu))
+call_rcu_busted(struct rcu_head *head, rcu_callback_t func)
{
/* This is a deliberate bug for testing purposes only! */
func(head);
@@ -523,7 +523,7 @@ static void srcu_torture_synchronize(void)
}
static void srcu_torture_call(struct rcu_head *head,
- void (*func)(struct rcu_head *head))
+ rcu_callback_t func)
{
call_srcu(srcu_ctlp, head, func);
}
diff --git a/kernel/rcu/srcu.c b/kernel/rcu/srcu.c
index d3fcb2ec8536..a63a1ea5a41b 100644
--- a/kernel/rcu/srcu.c
+++ b/kernel/rcu/srcu.c
@@ -298,11 +298,9 @@ int __srcu_read_lock(struct srcu_struct *sp)
int idx;
idx = READ_ONCE(sp->completed) & 0x1;
- preempt_disable();
__this_cpu_inc(sp->per_cpu_ref->c[idx]);
smp_mb(); /* B */ /* Avoid leaking the critical section. */
__this_cpu_inc(sp->per_cpu_ref->seq[idx]);
- preempt_enable();
return idx;
}
EXPORT_SYMBOL_GPL(__srcu_read_lock);
@@ -387,7 +385,7 @@ static void srcu_flip(struct srcu_struct *sp)
* srcu_struct structure.
*/
void call_srcu(struct srcu_struct *sp, struct rcu_head *head,
- void (*func)(struct rcu_head *head))
+ rcu_callback_t func)
{
unsigned long flags;
diff --git a/kernel/rcu/tiny.c b/kernel/rcu/tiny.c
index d0471056d0af..944b1b491ed8 100644
--- a/kernel/rcu/tiny.c
+++ b/kernel/rcu/tiny.c
@@ -44,7 +44,7 @@ struct rcu_ctrlblk;
static void __rcu_process_callbacks(struct rcu_ctrlblk *rcp);
static void rcu_process_callbacks(struct softirq_action *unused);
static void __call_rcu(struct rcu_head *head,
- void (*func)(struct rcu_head *rcu),
+ rcu_callback_t func,
struct rcu_ctrlblk *rcp);
#include "tiny_plugin.h"
@@ -203,7 +203,7 @@ EXPORT_SYMBOL_GPL(synchronize_sched);
* Helper function for call_rcu() and call_rcu_bh().
*/
static void __call_rcu(struct rcu_head *head,
- void (*func)(struct rcu_head *rcu),
+ rcu_callback_t func,
struct rcu_ctrlblk *rcp)
{
unsigned long flags;
@@ -229,7 +229,7 @@ static void __call_rcu(struct rcu_head *head,
* period. But since we have but one CPU, that would be after any
* quiescent state.
*/
-void call_rcu_sched(struct rcu_head *head, void (*func)(struct rcu_head *rcu))
+void call_rcu_sched(struct rcu_head *head, rcu_callback_t func)
{
__call_rcu(head, func, &rcu_sched_ctrlblk);
}
@@ -239,7 +239,7 @@ EXPORT_SYMBOL_GPL(call_rcu_sched);
* Post an RCU bottom-half callback to be invoked after any subsequent
* quiescent state.
*/
-void call_rcu_bh(struct rcu_head *head, void (*func)(struct rcu_head *rcu))
+void call_rcu_bh(struct rcu_head *head, rcu_callback_t func)
{
__call_rcu(head, func, &rcu_bh_ctrlblk);
}
diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c
index 42b317e13776..f07343b54fe5 100644
--- a/kernel/rcu/tree.c
+++ b/kernel/rcu/tree.c
@@ -97,7 +97,7 @@ struct rcu_state sname##_state = { \
.level = { &sname##_state.node[0] }, \
.rda = &sname##_data, \
.call = cr, \
- .fqs_state = RCU_GP_IDLE, \
+ .gp_state = RCU_GP_IDLE, \
.gpnum = 0UL - 300UL, \
.completed = 0UL - 300UL, \
.orphan_lock = __RAW_SPIN_LOCK_UNLOCKED(&sname##_state.orphan_lock), \
@@ -350,12 +350,14 @@ static void rcu_momentary_dyntick_idle(void)
*/
void rcu_note_context_switch(void)
{
+ barrier(); /* Avoid RCU read-side critical sections leaking down. */
trace_rcu_utilization(TPS("Start context switch"));
rcu_sched_qs();
rcu_preempt_note_context_switch();
if (unlikely(raw_cpu_read(rcu_sched_qs_mask)))
rcu_momentary_dyntick_idle();
trace_rcu_utilization(TPS("End context switch"));
+ barrier(); /* Avoid RCU read-side critical sections leaking up. */
}
EXPORT_SYMBOL_GPL(rcu_note_context_switch);
@@ -366,12 +368,19 @@ EXPORT_SYMBOL_GPL(rcu_note_context_switch);
* RCU flavors in desperate need of a quiescent state, which will normally
* be none of them). Either way, do a lightweight quiescent state for
* all RCU flavors.
+ *
+ * The barrier() calls are redundant in the common case when this is
+ * called externally, but just in case this is called from within this
+ * file.
+ *
*/
void rcu_all_qs(void)
{
+ barrier(); /* Avoid RCU read-side critical sections leaking down. */
if (unlikely(raw_cpu_read(rcu_sched_qs_mask)))
rcu_momentary_dyntick_idle();
this_cpu_inc(rcu_qs_ctr);
+ barrier(); /* Avoid RCU read-side critical sections leaking up. */
}
EXPORT_SYMBOL_GPL(rcu_all_qs);
@@ -1940,16 +1949,15 @@ static bool rcu_gp_fqs_check_wake(struct rcu_state *rsp, int *gfp)
/*
* Do one round of quiescent-state forcing.
*/
-static int rcu_gp_fqs(struct rcu_state *rsp, int fqs_state_in)
+static void rcu_gp_fqs(struct rcu_state *rsp, bool first_time)
{
- int fqs_state = fqs_state_in;
bool isidle = false;
unsigned long maxj;
struct rcu_node *rnp = rcu_get_root(rsp);
WRITE_ONCE(rsp->gp_activity, jiffies);
rsp->n_force_qs++;
- if (fqs_state == RCU_SAVE_DYNTICK) {
+ if (first_time) {
/* Collect dyntick-idle snapshots. */
if (is_sysidle_rcu_state(rsp)) {
isidle = true;
@@ -1958,7 +1966,6 @@ static int rcu_gp_fqs(struct rcu_state *rsp, int fqs_state_in)
force_qs_rnp(rsp, dyntick_save_progress_counter,
&isidle, &maxj);
rcu_sysidle_report_gp(rsp, isidle, maxj);
- fqs_state = RCU_FORCE_QS;
} else {
/* Handle dyntick-idle and offline CPUs. */
isidle = true;
@@ -1972,7 +1979,6 @@ static int rcu_gp_fqs(struct rcu_state *rsp, int fqs_state_in)
READ_ONCE(rsp->gp_flags) & ~RCU_GP_FLAG_FQS);
raw_spin_unlock_irq(&rnp->lock);
}
- return fqs_state;
}
/*
@@ -2036,7 +2042,7 @@ static void rcu_gp_cleanup(struct rcu_state *rsp)
/* Declare grace period done. */
WRITE_ONCE(rsp->completed, rsp->gpnum);
trace_rcu_grace_period(rsp->name, rsp->completed, TPS("end"));
- rsp->fqs_state = RCU_GP_IDLE;
+ rsp->gp_state = RCU_GP_IDLE;
rdp = this_cpu_ptr(rsp->rda);
/* Advance CBs to reduce false positives below. */
needgp = rcu_advance_cbs(rsp, rnp, rdp) || needgp;
@@ -2054,7 +2060,7 @@ static void rcu_gp_cleanup(struct rcu_state *rsp)
*/
static int __noreturn rcu_gp_kthread(void *arg)
{
- int fqs_state;
+ bool first_gp_fqs;
int gf;
unsigned long j;
int ret;
@@ -2086,7 +2092,7 @@ static int __noreturn rcu_gp_kthread(void *arg)
}
/* Handle quiescent-state forcing. */
- fqs_state = RCU_SAVE_DYNTICK;
+ first_gp_fqs = true;
j = jiffies_till_first_fqs;
if (j > HZ) {
j = HZ;
@@ -2114,7 +2120,8 @@ static int __noreturn rcu_gp_kthread(void *arg)
trace_rcu_grace_period(rsp->name,
READ_ONCE(rsp->gpnum),
TPS("fqsstart"));
- fqs_state = rcu_gp_fqs(rsp, fqs_state);
+ rcu_gp_fqs(rsp, first_gp_fqs);
+ first_gp_fqs = false;
trace_rcu_grace_period(rsp->name,
READ_ONCE(rsp->gpnum),
TPS("fqsend"));
@@ -3030,7 +3037,7 @@ static void rcu_leak_callback(struct rcu_head *rhp)
* is expected to specify a CPU.
*/
static void
-__call_rcu(struct rcu_head *head, void (*func)(struct rcu_head *rcu),
+__call_rcu(struct rcu_head *head, rcu_callback_t func,
struct rcu_state *rsp, int cpu, bool lazy)
{
unsigned long flags;
@@ -3101,7 +3108,7 @@ __call_rcu(struct rcu_head *head, void (*func)(struct rcu_head *rcu),
/*
* Queue an RCU-sched callback for invocation after a grace period.
*/
-void call_rcu_sched(struct rcu_head *head, void (*func)(struct rcu_head *rcu))
+void call_rcu_sched(struct rcu_head *head, rcu_callback_t func)
{
__call_rcu(head, func, &rcu_sched_state, -1, 0);
}
@@ -3110,7 +3117,7 @@ EXPORT_SYMBOL_GPL(call_rcu_sched);
/*
* Queue an RCU callback for invocation after a quicker grace period.
*/
-void call_rcu_bh(struct rcu_head *head, void (*func)(struct rcu_head *rcu))
+void call_rcu_bh(struct rcu_head *head, rcu_callback_t func)
{
__call_rcu(head, func, &rcu_bh_state, -1, 0);
}
@@ -3124,7 +3131,7 @@ EXPORT_SYMBOL_GPL(call_rcu_bh);
* function may only be called from __kfree_rcu().
*/
void kfree_call_rcu(struct rcu_head *head,
- void (*func)(struct rcu_head *rcu))
+ rcu_callback_t func)
{
__call_rcu(head, func, rcu_state_p, -1, 1);
}
@@ -4492,13 +4499,12 @@ static void __init rcu_init_geometry(void)
rcu_fanout_leaf, nr_cpu_ids);
/*
- * The boot-time rcu_fanout_leaf parameter is only permitted
- * to increase the leaf-level fanout, not decrease it. Of course,
- * the leaf-level fanout cannot exceed the number of bits in
- * the rcu_node masks. Complain and fall back to the compile-
- * time values if these limits are exceeded.
+ * The boot-time rcu_fanout_leaf parameter must be at least two
+ * and cannot exceed the number of bits in the rcu_node masks.
+ * Complain and fall back to the compile-time values if this
+ * limit is exceeded.
*/
- if (rcu_fanout_leaf < RCU_FANOUT_LEAF ||
+ if (rcu_fanout_leaf < 2 ||
rcu_fanout_leaf > sizeof(unsigned long) * 8) {
rcu_fanout_leaf = RCU_FANOUT_LEAF;
WARN_ON(1);
@@ -4515,10 +4521,13 @@ static void __init rcu_init_geometry(void)
/*
* The tree must be able to accommodate the configured number of CPUs.
- * If this limit is exceeded than we have a serious problem elsewhere.
+ * If this limit is exceeded, fall back to the compile-time values.
*/
- if (nr_cpu_ids > rcu_capacity[RCU_NUM_LVLS - 1])
- panic("rcu_init_geometry: rcu_capacity[] is too small");
+ if (nr_cpu_ids > rcu_capacity[RCU_NUM_LVLS - 1]) {
+ rcu_fanout_leaf = RCU_FANOUT_LEAF;
+ WARN_ON(1);
+ return;
+ }
/* Calculate the number of levels in the tree. */
for (i = 0; nr_cpu_ids > rcu_capacity[i]; i++) {
diff --git a/kernel/rcu/tree.h b/kernel/rcu/tree.h
index 191aa3678575..9fb4e238d4dc 100644
--- a/kernel/rcu/tree.h
+++ b/kernel/rcu/tree.h
@@ -417,13 +417,6 @@ struct rcu_data {
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
-
/* Values for nocb_defer_wakeup field in struct rcu_data. */
#define RCU_NOGP_WAKE_NOT 0
#define RCU_NOGP_WAKE 1
@@ -469,15 +462,13 @@ struct rcu_state {
/* shut bogus gcc warning) */
u8 flavor_mask; /* bit in flavor mask. */
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));
+ call_rcu_func_t call; /* call_rcu() flavor. */
int ncpus; /* # CPUs seen so far. */
/* 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. */
+ u8 boost ____cacheline_internodealigned_in_smp;
+ /* 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. */
@@ -545,8 +536,8 @@ struct rcu_state {
#define RCU_GP_FLAG_INIT 0x1 /* Need grace-period initialization. */
#define RCU_GP_FLAG_FQS 0x2 /* Need grace-period quiescent-state forcing. */
-/* Values for rcu_state structure's gp_flags field. */
-#define RCU_GP_WAIT_INIT 0 /* Initial state. */
+/* Values for rcu_state structure's gp_state field. */
+#define RCU_GP_IDLE 0 /* Initial state and no GP in progress. */
#define RCU_GP_WAIT_GPS 1 /* Wait for grace-period start. */
#define RCU_GP_DONE_GPS 2 /* Wait done for grace-period start. */
#define RCU_GP_WAIT_FQS 3 /* Wait for force-quiescent-state time. */
@@ -592,7 +583,7 @@ static int rcu_print_task_stall(struct rcu_node *rnp);
static int rcu_print_task_exp_stall(struct rcu_node *rnp);
static void rcu_preempt_check_blocked_tasks(struct rcu_node *rnp);
static void rcu_preempt_check_callbacks(void);
-void call_rcu(struct rcu_head *head, void (*func)(struct rcu_head *rcu));
+void call_rcu(struct rcu_head *head, rcu_callback_t func);
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);
diff --git a/kernel/rcu/tree_plugin.h b/kernel/rcu/tree_plugin.h
index ffeb99e550e8..630c19772630 100644
--- a/kernel/rcu/tree_plugin.h
+++ b/kernel/rcu/tree_plugin.h
@@ -657,7 +657,7 @@ static void rcu_preempt_do_callbacks(void)
/*
* Queue a preemptible-RCU callback for invocation after a grace period.
*/
-void call_rcu(struct rcu_head *head, void (*func)(struct rcu_head *rcu))
+void call_rcu(struct rcu_head *head, rcu_callback_t func)
{
__call_rcu(head, func, rcu_state_p, -1, 0);
}
@@ -1743,8 +1743,12 @@ static void print_cpu_stall_info(struct rcu_state *rsp, int cpu)
ticks_value = rsp->gpnum - rdp->gpnum;
}
print_cpu_stall_fast_no_hz(fast_no_hz, cpu);
- pr_err("\t%d: (%lu %s) idle=%03x/%llx/%d softirq=%u/%u fqs=%ld %s\n",
- cpu, ticks_value, ticks_title,
+ pr_err("\t%d-%c%c%c: (%lu %s) idle=%03x/%llx/%d softirq=%u/%u fqs=%ld %s\n",
+ cpu,
+ "O."[!!cpu_online(cpu)],
+ "o."[!!(rdp->grpmask & rdp->mynode->qsmaskinit)],
+ "N."[!!(rdp->grpmask & rdp->mynode->qsmaskinitnext)],
+ ticks_value, ticks_title,
atomic_read(&rdtp->dynticks) & 0xfff,
rdtp->dynticks_nesting, rdtp->dynticks_nmi_nesting,
rdp->softirq_snap, kstat_softirqs_cpu(RCU_SOFTIRQ, cpu),
diff --git a/kernel/rcu/tree_trace.c b/kernel/rcu/tree_trace.c
index 999c3672f990..ef7093cc9b5c 100644
--- a/kernel/rcu/tree_trace.c
+++ b/kernel/rcu/tree_trace.c
@@ -268,7 +268,7 @@ static void print_one_rcu_state(struct seq_file *m, struct rcu_state *rsp)
gpnum = rsp->gpnum;
seq_printf(m, "c=%ld g=%ld s=%d jfq=%ld j=%x ",
ulong2long(rsp->completed), ulong2long(gpnum),
- rsp->fqs_state,
+ rsp->gp_state,
(long)(rsp->jiffies_force_qs - jiffies),
(int)(jiffies & 0xffff));
seq_printf(m, "nfqs=%lu/nfqsng=%lu(%lu) fqlh=%lu oqlen=%ld/%ld\n",
diff --git a/kernel/rcu/update.c b/kernel/rcu/update.c
index 7a0b3bc7c5ed..5f748c5a40f0 100644
--- a/kernel/rcu/update.c
+++ b/kernel/rcu/update.c
@@ -534,7 +534,7 @@ static void rcu_spawn_tasks_kthread(void);
* Post an RCU-tasks callback. First call must be from process context
* after the scheduler if fully operational.
*/
-void call_rcu_tasks(struct rcu_head *rhp, void (*func)(struct rcu_head *rhp))
+void call_rcu_tasks(struct rcu_head *rhp, rcu_callback_t func)
{
unsigned long flags;
bool needwake;
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 2f9c92884817..c4e607873d6f 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -4022,6 +4022,7 @@ int sched_setscheduler_nocheck(struct task_struct *p, int policy,
{
return _sched_setscheduler(p, policy, param, false);
}
+EXPORT_SYMBOL_GPL(sched_setscheduler_nocheck);
static int
do_sched_setscheduler(pid_t pid, int policy, struct sched_param __user *param)
generated by cgit v1.2.3 (git 2.46.0) at 2025-07-21 15:26:59 +0000