diff options
Diffstat (limited to 'include')
| -rw-r--r-- | include/linux/context_tracking.h | 32 | ||||
| -rw-r--r-- | include/linux/context_tracking_state.h | 60 | ||||
| -rw-r--r-- | include/linux/entry-common.h | 2 | ||||
| -rw-r--r-- | include/linux/rcu_segcblist.h | 6 | ||||
| -rw-r--r-- | include/linux/rculist.h | 9 | ||||
| -rw-r--r-- | include/linux/rcupdate.h | 15 | ||||
| -rw-r--r-- | include/linux/rcutiny.h | 2 | ||||
| -rw-r--r-- | include/linux/rcutree.h | 2 | ||||
| -rw-r--r-- | include/linux/smp.h | 6 | ||||
| -rw-r--r-- | include/linux/srcutree.h | 15 | ||||
| -rw-r--r-- | include/trace/events/rcu.h | 20 |
11 files changed, 102 insertions, 67 deletions
diff --git a/include/linux/context_tracking.h b/include/linux/context_tracking.h index 6e76b9dba00e..d53092ffa9db 100644 --- a/include/linux/context_tracking.h +++ b/include/linux/context_tracking.h @@ -26,26 +26,26 @@ extern void user_exit_callable(void); static inline void user_enter(void) { if (context_tracking_enabled()) - ct_user_enter(CONTEXT_USER); + ct_user_enter(CT_STATE_USER); } static inline void user_exit(void) { if (context_tracking_enabled()) - ct_user_exit(CONTEXT_USER); + ct_user_exit(CT_STATE_USER); } /* Called with interrupts disabled. */ static __always_inline void user_enter_irqoff(void) { if (context_tracking_enabled()) - __ct_user_enter(CONTEXT_USER); + __ct_user_enter(CT_STATE_USER); } static __always_inline void user_exit_irqoff(void) { if (context_tracking_enabled()) - __ct_user_exit(CONTEXT_USER); + __ct_user_exit(CT_STATE_USER); } static inline enum ctx_state exception_enter(void) @@ -57,7 +57,7 @@ static inline enum ctx_state exception_enter(void) return 0; prev_ctx = __ct_state(); - if (prev_ctx != CONTEXT_KERNEL) + if (prev_ctx != CT_STATE_KERNEL) ct_user_exit(prev_ctx); return prev_ctx; @@ -67,7 +67,7 @@ static inline void exception_exit(enum ctx_state prev_ctx) { if (!IS_ENABLED(CONFIG_HAVE_CONTEXT_TRACKING_USER_OFFSTACK) && context_tracking_enabled()) { - if (prev_ctx != CONTEXT_KERNEL) + if (prev_ctx != CT_STATE_KERNEL) ct_user_enter(prev_ctx); } } @@ -75,7 +75,7 @@ static inline void exception_exit(enum ctx_state prev_ctx) static __always_inline bool context_tracking_guest_enter(void) { if (context_tracking_enabled()) - __ct_user_enter(CONTEXT_GUEST); + __ct_user_enter(CT_STATE_GUEST); return context_tracking_enabled_this_cpu(); } @@ -83,7 +83,7 @@ static __always_inline bool context_tracking_guest_enter(void) static __always_inline void context_tracking_guest_exit(void) { if (context_tracking_enabled()) - __ct_user_exit(CONTEXT_GUEST); + __ct_user_exit(CT_STATE_GUEST); } #define CT_WARN_ON(cond) WARN_ON(context_tracking_enabled() && (cond)) @@ -113,13 +113,17 @@ extern void ct_idle_enter(void); extern void ct_idle_exit(void); /* - * Is the current CPU in an extended quiescent state? + * Is RCU watching the current CPU (IOW, it is not in an extended quiescent state)? + * + * Note that this returns the actual boolean data (watching / not watching), + * whereas ct_rcu_watching() returns the RCU_WATCHING subvariable of + * context_tracking.state. * * No ordering, as we are sampling CPU-local information. */ -static __always_inline bool rcu_dynticks_curr_cpu_in_eqs(void) +static __always_inline bool rcu_is_watching_curr_cpu(void) { - return !(raw_atomic_read(this_cpu_ptr(&context_tracking.state)) & RCU_DYNTICKS_IDX); + return raw_atomic_read(this_cpu_ptr(&context_tracking.state)) & CT_RCU_WATCHING; } /* @@ -140,9 +144,9 @@ static __always_inline bool warn_rcu_enter(void) * lots of the actual reporting also relies on RCU. */ preempt_disable_notrace(); - if (rcu_dynticks_curr_cpu_in_eqs()) { + if (!rcu_is_watching_curr_cpu()) { ret = true; - ct_state_inc(RCU_DYNTICKS_IDX); + ct_state_inc(CT_RCU_WATCHING); } return ret; @@ -151,7 +155,7 @@ static __always_inline bool warn_rcu_enter(void) static __always_inline void warn_rcu_exit(bool rcu) { if (rcu) - ct_state_inc(RCU_DYNTICKS_IDX); + ct_state_inc(CT_RCU_WATCHING); preempt_enable_notrace(); } diff --git a/include/linux/context_tracking_state.h b/include/linux/context_tracking_state.h index bbff5f7f8803..7b8433d5a8ef 100644 --- a/include/linux/context_tracking_state.h +++ b/include/linux/context_tracking_state.h @@ -7,22 +7,22 @@ #include <linux/context_tracking_irq.h> /* Offset to allow distinguishing irq vs. task-based idle entry/exit. */ -#define DYNTICK_IRQ_NONIDLE ((LONG_MAX / 2) + 1) +#define CT_NESTING_IRQ_NONIDLE ((LONG_MAX / 2) + 1) enum ctx_state { - CONTEXT_DISABLED = -1, /* returned by ct_state() if unknown */ - CONTEXT_KERNEL = 0, - CONTEXT_IDLE = 1, - CONTEXT_USER = 2, - CONTEXT_GUEST = 3, - CONTEXT_MAX = 4, + CT_STATE_DISABLED = -1, /* returned by ct_state() if unknown */ + CT_STATE_KERNEL = 0, + CT_STATE_IDLE = 1, + CT_STATE_USER = 2, + CT_STATE_GUEST = 3, + CT_STATE_MAX = 4, }; -/* Even value for idle, else odd. */ -#define RCU_DYNTICKS_IDX CONTEXT_MAX +/* Odd value for watching, else even. */ +#define CT_RCU_WATCHING CT_STATE_MAX -#define CT_STATE_MASK (CONTEXT_MAX - 1) -#define CT_DYNTICKS_MASK (~CT_STATE_MASK) +#define CT_STATE_MASK (CT_STATE_MAX - 1) +#define CT_RCU_WATCHING_MASK (~CT_STATE_MASK) struct context_tracking { #ifdef CONFIG_CONTEXT_TRACKING_USER @@ -39,8 +39,8 @@ struct context_tracking { atomic_t state; #endif #ifdef CONFIG_CONTEXT_TRACKING_IDLE - long dynticks_nesting; /* Track process nesting level. */ - long dynticks_nmi_nesting; /* Track irq/NMI nesting level. */ + long nesting; /* Track process nesting level. */ + long nmi_nesting; /* Track irq/NMI nesting level. */ #endif }; @@ -56,47 +56,47 @@ static __always_inline int __ct_state(void) #endif #ifdef CONFIG_CONTEXT_TRACKING_IDLE -static __always_inline int ct_dynticks(void) +static __always_inline int ct_rcu_watching(void) { - return atomic_read(this_cpu_ptr(&context_tracking.state)) & CT_DYNTICKS_MASK; + return atomic_read(this_cpu_ptr(&context_tracking.state)) & CT_RCU_WATCHING_MASK; } -static __always_inline int ct_dynticks_cpu(int cpu) +static __always_inline int ct_rcu_watching_cpu(int cpu) { struct context_tracking *ct = per_cpu_ptr(&context_tracking, cpu); - return atomic_read(&ct->state) & CT_DYNTICKS_MASK; + return atomic_read(&ct->state) & CT_RCU_WATCHING_MASK; } -static __always_inline int ct_dynticks_cpu_acquire(int cpu) +static __always_inline int ct_rcu_watching_cpu_acquire(int cpu) { struct context_tracking *ct = per_cpu_ptr(&context_tracking, cpu); - return atomic_read_acquire(&ct->state) & CT_DYNTICKS_MASK; + return atomic_read_acquire(&ct->state) & CT_RCU_WATCHING_MASK; } -static __always_inline long ct_dynticks_nesting(void) +static __always_inline long ct_nesting(void) { - return __this_cpu_read(context_tracking.dynticks_nesting); + return __this_cpu_read(context_tracking.nesting); } -static __always_inline long ct_dynticks_nesting_cpu(int cpu) +static __always_inline long ct_nesting_cpu(int cpu) { struct context_tracking *ct = per_cpu_ptr(&context_tracking, cpu); - return ct->dynticks_nesting; + return ct->nesting; } -static __always_inline long ct_dynticks_nmi_nesting(void) +static __always_inline long ct_nmi_nesting(void) { - return __this_cpu_read(context_tracking.dynticks_nmi_nesting); + return __this_cpu_read(context_tracking.nmi_nesting); } -static __always_inline long ct_dynticks_nmi_nesting_cpu(int cpu) +static __always_inline long ct_nmi_nesting_cpu(int cpu) { struct context_tracking *ct = per_cpu_ptr(&context_tracking, cpu); - return ct->dynticks_nmi_nesting; + return ct->nmi_nesting; } #endif /* #ifdef CONFIG_CONTEXT_TRACKING_IDLE */ @@ -113,7 +113,7 @@ static __always_inline bool context_tracking_enabled_cpu(int cpu) return context_tracking_enabled() && per_cpu(context_tracking.active, cpu); } -static inline bool context_tracking_enabled_this_cpu(void) +static __always_inline bool context_tracking_enabled_this_cpu(void) { return context_tracking_enabled() && __this_cpu_read(context_tracking.active); } @@ -123,14 +123,14 @@ static inline bool context_tracking_enabled_this_cpu(void) * * Returns the current cpu's context tracking state if context tracking * is enabled. If context tracking is disabled, returns - * CONTEXT_DISABLED. This should be used primarily for debugging. + * CT_STATE_DISABLED. This should be used primarily for debugging. */ static __always_inline int ct_state(void) { int ret; if (!context_tracking_enabled()) - return CONTEXT_DISABLED; + return CT_STATE_DISABLED; preempt_disable(); ret = __ct_state(); diff --git a/include/linux/entry-common.h b/include/linux/entry-common.h index b0fb775a600d..1e50cdb83ae5 100644 --- a/include/linux/entry-common.h +++ b/include/linux/entry-common.h @@ -108,7 +108,7 @@ static __always_inline void enter_from_user_mode(struct pt_regs *regs) arch_enter_from_user_mode(regs); lockdep_hardirqs_off(CALLER_ADDR0); - CT_WARN_ON(__ct_state() != CONTEXT_USER); + CT_WARN_ON(__ct_state() != CT_STATE_USER); user_exit_irqoff(); instrumentation_begin(); diff --git a/include/linux/rcu_segcblist.h b/include/linux/rcu_segcblist.h index ba95c06675e1..2fdc2208f1ca 100644 --- a/include/linux/rcu_segcblist.h +++ b/include/linux/rcu_segcblist.h @@ -185,11 +185,7 @@ struct rcu_cblist { * ---------------------------------------------------------------------------- */ #define SEGCBLIST_ENABLED BIT(0) -#define SEGCBLIST_RCU_CORE BIT(1) -#define SEGCBLIST_LOCKING BIT(2) -#define SEGCBLIST_KTHREAD_CB BIT(3) -#define SEGCBLIST_KTHREAD_GP BIT(4) -#define SEGCBLIST_OFFLOADED BIT(5) +#define SEGCBLIST_OFFLOADED BIT(1) struct rcu_segcblist { struct rcu_head *head; diff --git a/include/linux/rculist.h b/include/linux/rculist.h index 3dc1e58865f7..14dfa6008467 100644 --- a/include/linux/rculist.h +++ b/include/linux/rculist.h @@ -191,7 +191,10 @@ static inline void hlist_del_init_rcu(struct hlist_node *n) * @old : the element to be replaced * @new : the new element to insert * - * The @old entry will be replaced with the @new entry atomically. + * The @old entry will be replaced with the @new entry atomically from + * the perspective of concurrent readers. It is the caller's responsibility + * to synchronize with concurrent updaters, if any. + * * Note: @old should not be empty. */ static inline void list_replace_rcu(struct list_head *old, @@ -519,7 +522,9 @@ static inline void hlist_del_rcu(struct hlist_node *n) * @old : the element to be replaced * @new : the new element to insert * - * The @old entry will be replaced with the @new entry atomically. + * The @old entry will be replaced with the @new entry atomically from + * the perspective of concurrent readers. It is the caller's responsibility + * to synchronize with concurrent updaters, if any. */ static inline void hlist_replace_rcu(struct hlist_node *old, struct hlist_node *new) diff --git a/include/linux/rcupdate.h b/include/linux/rcupdate.h index 13f6f00aecf9..58d84c59f3dd 100644 --- a/include/linux/rcupdate.h +++ b/include/linux/rcupdate.h @@ -34,10 +34,12 @@ #define ULONG_CMP_GE(a, b) (ULONG_MAX / 2 >= (a) - (b)) #define ULONG_CMP_LT(a, b) (ULONG_MAX / 2 < (a) - (b)) +#define RCU_SEQ_CTR_SHIFT 2 +#define RCU_SEQ_STATE_MASK ((1 << RCU_SEQ_CTR_SHIFT) - 1) + /* Exported common interfaces */ void call_rcu(struct rcu_head *head, rcu_callback_t func); void rcu_barrier_tasks(void); -void rcu_barrier_tasks_rude(void); void synchronize_rcu(void); struct rcu_gp_oldstate; @@ -144,11 +146,18 @@ void rcu_init_nohz(void); int rcu_nocb_cpu_offload(int cpu); int rcu_nocb_cpu_deoffload(int cpu); void rcu_nocb_flush_deferred_wakeup(void); + +#define RCU_NOCB_LOCKDEP_WARN(c, s) RCU_LOCKDEP_WARN(c, s) + #else /* #ifdef CONFIG_RCU_NOCB_CPU */ + static inline void rcu_init_nohz(void) { } static inline int rcu_nocb_cpu_offload(int cpu) { return -EINVAL; } static inline int rcu_nocb_cpu_deoffload(int cpu) { return 0; } static inline void rcu_nocb_flush_deferred_wakeup(void) { } + +#define RCU_NOCB_LOCKDEP_WARN(c, s) + #endif /* #else #ifdef CONFIG_RCU_NOCB_CPU */ /* @@ -165,6 +174,7 @@ static inline void rcu_nocb_flush_deferred_wakeup(void) { } } while (0) void call_rcu_tasks(struct rcu_head *head, rcu_callback_t func); void synchronize_rcu_tasks(void); +void rcu_tasks_torture_stats_print(char *tt, char *tf); # else # define rcu_tasks_classic_qs(t, preempt) do { } while (0) # define call_rcu_tasks call_rcu @@ -191,6 +201,7 @@ void rcu_tasks_trace_qs_blkd(struct task_struct *t); rcu_tasks_trace_qs_blkd(t); \ } \ } while (0) +void rcu_tasks_trace_torture_stats_print(char *tt, char *tf); # else # define rcu_tasks_trace_qs(t) do { } while (0) # endif @@ -202,8 +213,8 @@ do { \ } while (0) # ifdef CONFIG_TASKS_RUDE_RCU -void call_rcu_tasks_rude(struct rcu_head *head, rcu_callback_t func); void synchronize_rcu_tasks_rude(void); +void rcu_tasks_rude_torture_stats_print(char *tt, char *tf); # endif #define rcu_note_voluntary_context_switch(t) rcu_tasks_qs(t, false) diff --git a/include/linux/rcutiny.h b/include/linux/rcutiny.h index d9ac7b136aea..cf2b5a188f78 100644 --- a/include/linux/rcutiny.h +++ b/include/linux/rcutiny.h @@ -158,7 +158,7 @@ void rcu_scheduler_starting(void); static inline void rcu_end_inkernel_boot(void) { } static inline bool rcu_inkernel_boot_has_ended(void) { return true; } static inline bool rcu_is_watching(void) { return true; } -static inline void rcu_momentary_dyntick_idle(void) { } +static inline void rcu_momentary_eqs(void) { } static inline void kfree_rcu_scheduler_running(void) { } static inline bool rcu_gp_might_be_stalled(void) { return false; } diff --git a/include/linux/rcutree.h b/include/linux/rcutree.h index 254244202ea9..7dbde2b6f714 100644 --- a/include/linux/rcutree.h +++ b/include/linux/rcutree.h @@ -37,7 +37,7 @@ void synchronize_rcu_expedited(void); void kvfree_call_rcu(struct rcu_head *head, void *ptr); void rcu_barrier(void); -void rcu_momentary_dyntick_idle(void); +void rcu_momentary_eqs(void); void kfree_rcu_scheduler_running(void); bool rcu_gp_might_be_stalled(void); diff --git a/include/linux/smp.h b/include/linux/smp.h index fcd61dfe2af3..3871bd32018f 100644 --- a/include/linux/smp.h +++ b/include/linux/smp.h @@ -294,4 +294,10 @@ int smpcfd_prepare_cpu(unsigned int cpu); int smpcfd_dead_cpu(unsigned int cpu); int smpcfd_dying_cpu(unsigned int cpu); +#ifdef CONFIG_CSD_LOCK_WAIT_DEBUG +bool csd_lock_is_stuck(void); +#else +static inline bool csd_lock_is_stuck(void) { return false; } +#endif + #endif /* __LINUX_SMP_H */ diff --git a/include/linux/srcutree.h b/include/linux/srcutree.h index 8f3f72480e78..ed57598394de 100644 --- a/include/linux/srcutree.h +++ b/include/linux/srcutree.h @@ -129,10 +129,23 @@ struct srcu_struct { #define SRCU_STATE_SCAN1 1 #define SRCU_STATE_SCAN2 2 +/* + * Values for initializing gp sequence fields. Higher values allow wrap arounds to + * occur earlier. + * The second value with state is useful in the case of static initialization of + * srcu_usage where srcu_gp_seq_needed is expected to have some state value in its + * lower bits (or else it will appear to be already initialized within + * the call check_init_srcu_struct()). + */ +#define SRCU_GP_SEQ_INITIAL_VAL ((0UL - 100UL) << RCU_SEQ_CTR_SHIFT) +#define SRCU_GP_SEQ_INITIAL_VAL_WITH_STATE (SRCU_GP_SEQ_INITIAL_VAL - 1) + #define __SRCU_USAGE_INIT(name) \ { \ .lock = __SPIN_LOCK_UNLOCKED(name.lock), \ - .srcu_gp_seq_needed = -1UL, \ + .srcu_gp_seq = SRCU_GP_SEQ_INITIAL_VAL, \ + .srcu_gp_seq_needed = SRCU_GP_SEQ_INITIAL_VAL_WITH_STATE, \ + .srcu_gp_seq_needed_exp = SRCU_GP_SEQ_INITIAL_VAL, \ .work = __DELAYED_WORK_INITIALIZER(name.work, NULL, 0), \ } diff --git a/include/trace/events/rcu.h b/include/trace/events/rcu.h index 31b3e0d3e65f..e81431deaa50 100644 --- a/include/trace/events/rcu.h +++ b/include/trace/events/rcu.h @@ -466,40 +466,40 @@ TRACE_EVENT(rcu_stall_warning, /* * Tracepoint for dyntick-idle entry/exit events. These take 2 strings * as argument: - * polarity: "Start", "End", "StillNonIdle" for entering, exiting or still not - * being in dyntick-idle mode. + * polarity: "Start", "End", "StillWatching" for entering, exiting or still not + * being in EQS mode. * context: "USER" or "IDLE" or "IRQ". - * NMIs nested in IRQs are inferred with dynticks_nesting > 1 in IRQ context. + * NMIs nested in IRQs are inferred with nesting > 1 in IRQ context. * * These events also take a pair of numbers, which indicate the nesting * depth before and after the event of interest, and a third number that is - * the ->dynticks counter. Note that task-related and interrupt-related + * the RCU_WATCHING 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(rcu_dyntick, +TRACE_EVENT_RCU(rcu_watching, - TP_PROTO(const char *polarity, long oldnesting, long newnesting, int dynticks), + TP_PROTO(const char *polarity, long oldnesting, long newnesting, int counter), - TP_ARGS(polarity, oldnesting, newnesting, dynticks), + TP_ARGS(polarity, oldnesting, newnesting, counter), TP_STRUCT__entry( __field(const char *, polarity) __field(long, oldnesting) __field(long, newnesting) - __field(int, dynticks) + __field(int, counter) ), TP_fast_assign( __entry->polarity = polarity; __entry->oldnesting = oldnesting; __entry->newnesting = newnesting; - __entry->dynticks = dynticks; + __entry->counter = counter; ), TP_printk("%s %lx %lx %#3x", __entry->polarity, __entry->oldnesting, __entry->newnesting, - __entry->dynticks & 0xfff) + __entry->counter & 0xfff) ); /* |