diff options
Diffstat (limited to 'include')
| -rw-r--r-- | include/linux/genetlink.h | 3 | ||||
| -rw-r--r-- | include/linux/netfilter/nfnetlink.h | 3 | ||||
| -rw-r--r-- | include/linux/percpu-refcount.h | 6 | ||||
| -rw-r--r-- | include/linux/rcupdate.h | 25 | ||||
| -rw-r--r-- | include/linux/rcutiny.h | 1 | ||||
| -rw-r--r-- | include/linux/rcutree.h | 1 | ||||
| -rw-r--r-- | include/linux/rtnetlink.h | 3 | ||||
| -rw-r--r-- | include/linux/seqlock.h | 3 | ||||
| -rw-r--r-- | include/linux/srcutree.h | 8 | ||||
| -rw-r--r-- | include/linux/torture.h | 8 | ||||
| -rw-r--r-- | include/linux/tracepoint.h | 5 | ||||
| -rw-r--r-- | include/trace/events/rcu.h | 75 |
12 files changed, 51 insertions, 90 deletions
diff --git a/include/linux/genetlink.h b/include/linux/genetlink.h index ecc2928e8046..bc738504ab4a 100644 --- a/include/linux/genetlink.h +++ b/include/linux/genetlink.h @@ -31,8 +31,7 @@ extern wait_queue_head_t genl_sk_destructing_waitq; * @p: The pointer to read, prior to dereferencing * * Return the value of the specified RCU-protected pointer, but omit - * both the smp_read_barrier_depends() and the READ_ONCE(), because - * caller holds genl mutex. + * the READ_ONCE(), because caller holds genl mutex. */ #define genl_dereference(p) \ rcu_dereference_protected(p, lockdep_genl_is_held()) diff --git a/include/linux/netfilter/nfnetlink.h b/include/linux/netfilter/nfnetlink.h index 495ba4dd9da5..34551f8aaf9d 100644 --- a/include/linux/netfilter/nfnetlink.h +++ b/include/linux/netfilter/nfnetlink.h @@ -67,8 +67,7 @@ static inline bool lockdep_nfnl_is_held(__u8 subsys_id) * @ss: The nfnetlink subsystem ID * * Return the value of the specified RCU-protected pointer, but omit - * both the smp_read_barrier_depends() and the READ_ONCE(), because - * caller holds the NFNL subsystem mutex. + * the READ_ONCE(), because caller holds the NFNL subsystem mutex. */ #define nfnl_dereference(p, ss) \ rcu_dereference_protected(p, lockdep_nfnl_is_held(ss)) diff --git a/include/linux/percpu-refcount.h b/include/linux/percpu-refcount.h index 6658d9ee5257..864d167a1073 100644 --- a/include/linux/percpu-refcount.h +++ b/include/linux/percpu-refcount.h @@ -139,12 +139,12 @@ static inline bool __ref_is_percpu(struct percpu_ref *ref, * when using it as a pointer, __PERCPU_REF_ATOMIC may be set in * between contaminating the pointer value, meaning that * READ_ONCE() is required when fetching it. + * + * The smp_read_barrier_depends() implied by READ_ONCE() pairs + * with smp_store_release() in __percpu_ref_switch_to_percpu(). */ percpu_ptr = READ_ONCE(ref->percpu_count_ptr); - /* paired with smp_store_release() in __percpu_ref_switch_to_percpu() */ - smp_read_barrier_depends(); - /* * Theoretically, the following could test just ATOMIC; however, * then we'd have to mask off DEAD separately as DEAD may be diff --git a/include/linux/rcupdate.h b/include/linux/rcupdate.h index a6ddc42f87a5..043d04784675 100644 --- a/include/linux/rcupdate.h +++ b/include/linux/rcupdate.h @@ -197,7 +197,7 @@ static inline void exit_tasks_rcu_finish(void) { } #define cond_resched_rcu_qs() \ do { \ if (!cond_resched()) \ - rcu_note_voluntary_context_switch(current); \ + rcu_note_voluntary_context_switch_lite(current); \ } while (0) /* @@ -433,12 +433,12 @@ static inline void rcu_preempt_sleep_check(void) { } * @p: The pointer to read * * Return the value of the specified RCU-protected pointer, but omit the - * smp_read_barrier_depends() and keep the READ_ONCE(). This is useful - * when the value of this pointer is accessed, but the pointer is not - * dereferenced, for example, when testing an RCU-protected pointer against - * NULL. Although rcu_access_pointer() may also be used in cases where - * update-side locks prevent the value of the pointer from changing, you - * should instead use rcu_dereference_protected() for this use case. + * lockdep checks for being in an RCU read-side critical section. This is + * useful when the value of this pointer is accessed, but the pointer is + * not dereferenced, for example, when testing an RCU-protected pointer + * against NULL. Although rcu_access_pointer() may also be used in cases + * where update-side locks prevent the value of the pointer from changing, + * you should instead use rcu_dereference_protected() for this use case. * * It is also permissible to use rcu_access_pointer() when read-side * access to the pointer was removed at least one grace period ago, as @@ -521,12 +521,11 @@ static inline void rcu_preempt_sleep_check(void) { } * @c: The conditions under which the dereference will take place * * Return the value of the specified RCU-protected pointer, but omit - * both the smp_read_barrier_depends() and the READ_ONCE(). This - * is useful in cases where update-side locks prevent the value of the - * pointer from changing. Please note that this primitive does *not* - * prevent the compiler from repeating this reference or combining it - * with other references, so it should not be used without protection - * of appropriate locks. + * the READ_ONCE(). This is useful in cases where update-side locks + * prevent the value of the pointer from changing. Please note that this + * primitive does *not* prevent the compiler from repeating this reference + * or combining it with other references, so it should not be used without + * protection of appropriate locks. * * This function is only for update-side use. Using this function * when protected only by rcu_read_lock() will result in infrequent diff --git a/include/linux/rcutiny.h b/include/linux/rcutiny.h index b3dbf9502fd0..ce9beec35e34 100644 --- a/include/linux/rcutiny.h +++ b/include/linux/rcutiny.h @@ -111,7 +111,6 @@ static inline void rcu_cpu_stall_reset(void) { } static inline void rcu_idle_enter(void) { } static inline void rcu_idle_exit(void) { } static inline void rcu_irq_enter(void) { } -static inline bool rcu_irq_enter_disabled(void) { return false; } static inline void rcu_irq_exit_irqson(void) { } static inline void rcu_irq_enter_irqson(void) { } static inline void rcu_irq_exit(void) { } diff --git a/include/linux/rcutree.h b/include/linux/rcutree.h index 37d6fd3b7ff8..fd996cdf1833 100644 --- a/include/linux/rcutree.h +++ b/include/linux/rcutree.h @@ -85,7 +85,6 @@ void rcu_irq_enter(void); void rcu_irq_exit(void); void rcu_irq_enter_irqson(void); void rcu_irq_exit_irqson(void); -bool rcu_irq_enter_disabled(void); void exit_rcu(void); diff --git a/include/linux/rtnetlink.h b/include/linux/rtnetlink.h index 2032ce2eb20b..1eadec3fc228 100644 --- a/include/linux/rtnetlink.h +++ b/include/linux/rtnetlink.h @@ -70,8 +70,7 @@ static inline bool lockdep_rtnl_is_held(void) * @p: The pointer to read, prior to dereferencing * * Return the value of the specified RCU-protected pointer, but omit - * both the smp_read_barrier_depends() and the READ_ONCE(), because - * caller holds RTNL. + * the READ_ONCE(), because caller holds RTNL. */ #define rtnl_dereference(p) \ rcu_dereference_protected(p, lockdep_rtnl_is_held()) diff --git a/include/linux/seqlock.h b/include/linux/seqlock.h index f189a8a3bbb8..bcf4cf26b8c8 100644 --- a/include/linux/seqlock.h +++ b/include/linux/seqlock.h @@ -278,9 +278,8 @@ static inline void raw_write_seqcount_barrier(seqcount_t *s) static inline int raw_read_seqcount_latch(seqcount_t *s) { - int seq = READ_ONCE(s->sequence); /* Pairs with the first smp_wmb() in raw_write_seqcount_latch() */ - smp_read_barrier_depends(); + int seq = READ_ONCE(s->sequence); /* ^^^ */ return seq; } diff --git a/include/linux/srcutree.h b/include/linux/srcutree.h index a949f4f9e4d7..4eda108abee0 100644 --- a/include/linux/srcutree.h +++ b/include/linux/srcutree.h @@ -40,7 +40,7 @@ struct srcu_data { unsigned long srcu_unlock_count[2]; /* Unlocks per CPU. */ /* Update-side state. */ - raw_spinlock_t __private lock ____cacheline_internodealigned_in_smp; + spinlock_t __private lock ____cacheline_internodealigned_in_smp; struct rcu_segcblist srcu_cblist; /* List of callbacks.*/ unsigned long srcu_gp_seq_needed; /* Furthest future GP needed. */ unsigned long srcu_gp_seq_needed_exp; /* Furthest future exp GP. */ @@ -58,7 +58,7 @@ struct srcu_data { * Node in SRCU combining tree, similar in function to rcu_data. */ struct srcu_node { - raw_spinlock_t __private lock; + spinlock_t __private lock; unsigned long srcu_have_cbs[4]; /* GP seq for children */ /* having CBs, but only */ /* is > ->srcu_gq_seq. */ @@ -78,7 +78,7 @@ struct srcu_struct { struct srcu_node *level[RCU_NUM_LVLS + 1]; /* First node at each level. */ struct mutex srcu_cb_mutex; /* Serialize CB preparation. */ - raw_spinlock_t __private lock; /* Protect counters */ + spinlock_t __private lock; /* Protect counters */ struct mutex srcu_gp_mutex; /* Serialize GP work. */ unsigned int srcu_idx; /* Current rdr array element. */ unsigned long srcu_gp_seq; /* Grace-period seq #. */ @@ -107,7 +107,7 @@ struct srcu_struct { #define __SRCU_STRUCT_INIT(name) \ { \ .sda = &name##_srcu_data, \ - .lock = __RAW_SPIN_LOCK_UNLOCKED(name.lock), \ + .lock = __SPIN_LOCK_UNLOCKED(name.lock), \ .srcu_gp_seq_needed = 0 - 1, \ __SRCU_DEP_MAP_INIT(name) \ } diff --git a/include/linux/torture.h b/include/linux/torture.h index a45702eb3e7b..66272862070b 100644 --- a/include/linux/torture.h +++ b/include/linux/torture.h @@ -79,7 +79,7 @@ void stutter_wait(const char *title); int torture_stutter_init(int s); /* Initialization and cleanup. */ -bool torture_init_begin(char *ttype, bool v, int *runnable); +bool torture_init_begin(char *ttype, bool v); void torture_init_end(void); bool torture_cleanup_begin(void); void torture_cleanup_end(void); @@ -96,4 +96,10 @@ void _torture_stop_kthread(char *m, struct task_struct **tp); #define torture_stop_kthread(n, tp) \ _torture_stop_kthread("Stopping " #n " task", &(tp)) +#ifdef CONFIG_PREEMPT +#define torture_preempt_schedule() preempt_schedule() +#else +#define torture_preempt_schedule() +#endif + #endif /* __LINUX_TORTURE_H */ diff --git a/include/linux/tracepoint.h b/include/linux/tracepoint.h index a26ffbe09e71..c94f466d57ef 100644 --- a/include/linux/tracepoint.h +++ b/include/linux/tracepoint.h @@ -137,11 +137,8 @@ extern void syscall_unregfunc(void); \ if (!(cond)) \ return; \ - if (rcucheck) { \ - if (WARN_ON_ONCE(rcu_irq_enter_disabled())) \ - return; \ + if (rcucheck) \ rcu_irq_enter_irqson(); \ - } \ rcu_read_lock_sched_notrace(); \ it_func_ptr = rcu_dereference_sched((tp)->funcs); \ if (it_func_ptr) { \ diff --git a/include/trace/events/rcu.h b/include/trace/events/rcu.h index 59d40c454aa0..0b50fda80db0 100644 --- a/include/trace/events/rcu.h +++ b/include/trace/events/rcu.h @@ -243,6 +243,7 @@ TRACE_EVENT(rcu_exp_funnel_lock, __entry->grphi, __entry->gpevent) ); +#ifdef CONFIG_RCU_NOCB_CPU /* * Tracepoint for RCU no-CBs CPU callback handoffs. This event is intended * to assist debugging of these handoffs. @@ -285,6 +286,7 @@ TRACE_EVENT(rcu_nocb_wake, TP_printk("%s %d %s", __entry->rcuname, __entry->cpu, __entry->reason) ); +#endif /* * Tracepoint for tasks blocking within preemptible-RCU read-side @@ -421,76 +423,40 @@ TRACE_EVENT(rcu_fqs, /* * Tracepoint for dyntick-idle entry/exit events. These take a string - * as argument: "Start" for entering dyntick-idle mode, "End" for - * leaving it, "--=" for events moving towards idle, and "++=" for events - * moving away from idle. "Error on entry: not idle task" and "Error on - * exit: not idle task" indicate that a non-idle task is erroneously - * toying with the idle loop. + * as argument: "Start" for entering dyntick-idle mode, "Startirq" for + * entering it from irq/NMI, "End" for leaving it, "Endirq" for leaving it + * to irq/NMI, "--=" for events moving towards idle, and "++=" for events + * moving away from idle. * * These events also take a pair of numbers, which indicate the nesting - * depth before and after the event of interest. Note that task-related - * events use the upper bits of each number, while interrupt-related - * events use the lower bits. + * depth before and after the event of interest, and a third number that is + * the ->dynticks counter. Note that task-related and interrupt-related + * events use two separate counters, and that the "++=" and "--=" events + * for irq/NMI will change the counter by two, otherwise by one. */ TRACE_EVENT(rcu_dyntick, - TP_PROTO(const char *polarity, long long oldnesting, long long newnesting), + TP_PROTO(const char *polarity, long oldnesting, long newnesting, atomic_t dynticks), - TP_ARGS(polarity, oldnesting, newnesting), + TP_ARGS(polarity, oldnesting, newnesting, dynticks), TP_STRUCT__entry( __field(const char *, polarity) - __field(long long, oldnesting) - __field(long long, newnesting) + __field(long, oldnesting) + __field(long, newnesting) + __field(int, dynticks) ), TP_fast_assign( __entry->polarity = polarity; __entry->oldnesting = oldnesting; __entry->newnesting = newnesting; + __entry->dynticks = atomic_read(&dynticks); ), - TP_printk("%s %llx %llx", __entry->polarity, - __entry->oldnesting, __entry->newnesting) -); - -/* - * Tracepoint for RCU preparation for idle, the goal being to get RCU - * processing done so that the current CPU can shut off its scheduling - * clock and enter dyntick-idle mode. One way to accomplish this is - * to drain all RCU callbacks from this CPU, and the other is to have - * done everything RCU requires for the current grace period. In this - * latter case, the CPU will be awakened at the end of the current grace - * period in order to process the remainder of its callbacks. - * - * These tracepoints take a string as argument: - * - * "No callbacks": Nothing to do, no callbacks on this CPU. - * "In holdoff": Nothing to do, holding off after unsuccessful attempt. - * "Begin holdoff": Attempt failed, don't retry until next jiffy. - * "Dyntick with callbacks": Entering dyntick-idle despite callbacks. - * "Dyntick with lazy callbacks": Entering dyntick-idle w/lazy callbacks. - * "More callbacks": Still more callbacks, try again to clear them out. - * "Callbacks drained": All callbacks processed, off to dyntick idle! - * "Timer": Timer fired to cause CPU to continue processing callbacks. - * "Demigrate": Timer fired on wrong CPU, woke up correct CPU. - * "Cleanup after idle": Idle exited, timer canceled. - */ -TRACE_EVENT(rcu_prep_idle, - - TP_PROTO(const char *reason), - - TP_ARGS(reason), - - TP_STRUCT__entry( - __field(const char *, reason) - ), - - TP_fast_assign( - __entry->reason = reason; - ), - - TP_printk("%s", __entry->reason) + TP_printk("%s %lx %lx %#3x", __entry->polarity, + __entry->oldnesting, __entry->newnesting, + __entry->dynticks & 0xfff) ); /* @@ -799,8 +765,7 @@ TRACE_EVENT(rcu_barrier, grplo, grphi, gp_tasks) do { } \ while (0) #define trace_rcu_fqs(rcuname, gpnum, cpu, qsevent) do { } while (0) -#define trace_rcu_dyntick(polarity, oldnesting, newnesting) do { } while (0) -#define trace_rcu_prep_idle(reason) do { } while (0) +#define trace_rcu_dyntick(polarity, oldnesting, newnesting, dyntick) do { } while (0) #define trace_rcu_callback(rcuname, rhp, qlen_lazy, qlen) do { } while (0) #define trace_rcu_kfree_callback(rcuname, rhp, offset, qlen_lazy, qlen) \ do { } while (0) |