123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250251252253254255256257258259260261262263264265266267268269270271272273274275276277278279280281282283284285286287288289290291292293294295296297298299300301302303304305306307308309310311312313314315316317318319320321322323324325326327328329330331332333334335336337338339340341342343344345346347348349350351352353354355356357358359360361362363364365366367368369370371372373374375376377378379380381382383384385386387388389390391392393394395396397398399400401402403404405406407408409410411412413414415416417418419420421422423424425426427428429430431432433434435436437438439440441442443444445446447448449450451452453454455456457458459460461462463464465466467468469470471472473474475476477478479480481482483484485486487488489490491492493494495496497498499500501502503504505506507508509510511512513514515516517518519520521522523524525526527528529530531532533534535536537538539540541542543544545546547548549550551552553554555556557558559560561562563564565566567568569570571572573574575576577578579580581582583584585586587588589590591592593594595596597598599600601602603604605606607608609610611612613614615616617618619620621622623624625626627628629630631632633634635636637638639640641642643644645646647648649650651652653654655656657658659660661662663664665666667668669670671672673674675676677678679680681682683684685686687688689690691692693694695696697698699700701702703704705706707708709710711712713714715716717718719720721722723724725726727728729730731732733734735736737738739740741742743744745746747748749750751752753754755756757758759760761762763764765766767768769770771772773774775776777778779780781782783784785786787788789790791792793794795796797798799800801802803804805806807808809810811812813814815816817818819820821822823824825826827828829830831832833834835836837838839840841842843844845846847848849850851852853854855856857858 |
- /* SPDX-License-Identifier: GPL-2.0 */
- /* interrupt.h */
- #ifndef _LINUX_INTERRUPT_H
- #define _LINUX_INTERRUPT_H
- #include <linux/kernel.h>
- #include <linux/bitops.h>
- #include <linux/cpumask.h>
- #include <linux/irqreturn.h>
- #include <linux/irqnr.h>
- #include <linux/hardirq.h>
- #include <linux/irqflags.h>
- #include <linux/hrtimer.h>
- #include <linux/kref.h>
- #include <linux/workqueue.h>
- #include <linux/jump_label.h>
- #include <linux/atomic.h>
- #include <asm/ptrace.h>
- #include <asm/irq.h>
- #include <asm/sections.h>
- /*
- * These correspond to the IORESOURCE_IRQ_* defines in
- * linux/ioport.h to select the interrupt line behaviour. When
- * requesting an interrupt without specifying a IRQF_TRIGGER, the
- * setting should be assumed to be "as already configured", which
- * may be as per machine or firmware initialisation.
- */
- #define IRQF_TRIGGER_NONE 0x00000000
- #define IRQF_TRIGGER_RISING 0x00000001
- #define IRQF_TRIGGER_FALLING 0x00000002
- #define IRQF_TRIGGER_HIGH 0x00000004
- #define IRQF_TRIGGER_LOW 0x00000008
- #define IRQF_TRIGGER_MASK (IRQF_TRIGGER_HIGH | IRQF_TRIGGER_LOW | \
- IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING)
- #define IRQF_TRIGGER_PROBE 0x00000010
- /*
- * These flags used only by the kernel as part of the
- * irq handling routines.
- *
- * IRQF_SHARED - allow sharing the irq among several devices
- * IRQF_PROBE_SHARED - set by callers when they expect sharing mismatches to occur
- * IRQF_TIMER - Flag to mark this interrupt as timer interrupt
- * IRQF_PERCPU - Interrupt is per cpu
- * IRQF_NOBALANCING - Flag to exclude this interrupt from irq balancing
- * IRQF_IRQPOLL - Interrupt is used for polling (only the interrupt that is
- * registered first in a shared interrupt is considered for
- * performance reasons)
- * IRQF_ONESHOT - Interrupt is not reenabled after the hardirq handler finished.
- * Used by threaded interrupts which need to keep the
- * irq line disabled until the threaded handler has been run.
- * IRQF_NO_SUSPEND - Do not disable this IRQ during suspend. Does not guarantee
- * that this interrupt will wake the system from a suspended
- * state. See Documentation/power/suspend-and-interrupts.rst
- * IRQF_FORCE_RESUME - Force enable it on resume even if IRQF_NO_SUSPEND is set
- * IRQF_NO_THREAD - Interrupt cannot be threaded
- * IRQF_EARLY_RESUME - Resume IRQ early during syscore instead of at device
- * resume time.
- * IRQF_COND_SUSPEND - If the IRQ is shared with a NO_SUSPEND user, execute this
- * interrupt handler after suspending interrupts. For system
- * wakeup devices users need to implement wakeup detection in
- * their interrupt handlers.
- * IRQF_NO_AUTOEN - Don't enable IRQ or NMI automatically when users request it.
- * Users will enable it explicitly by enable_irq() or enable_nmi()
- * later.
- * IRQF_NO_DEBUG - Exclude from runnaway detection for IPI and similar handlers,
- * depends on IRQF_PERCPU.
- */
- #define IRQF_SHARED 0x00000080
- #define IRQF_PROBE_SHARED 0x00000100
- #define __IRQF_TIMER 0x00000200
- #define IRQF_PERCPU 0x00000400
- #define IRQF_NOBALANCING 0x00000800
- #define IRQF_IRQPOLL 0x00001000
- #define IRQF_ONESHOT 0x00002000
- #define IRQF_NO_SUSPEND 0x00004000
- #define IRQF_FORCE_RESUME 0x00008000
- #define IRQF_NO_THREAD 0x00010000
- #define IRQF_EARLY_RESUME 0x00020000
- #define IRQF_COND_SUSPEND 0x00040000
- #define IRQF_NO_AUTOEN 0x00080000
- #define IRQF_NO_DEBUG 0x00100000
- #define IRQF_TIMER (__IRQF_TIMER | IRQF_NO_SUSPEND | IRQF_NO_THREAD)
- /*
- * These values can be returned by request_any_context_irq() and
- * describe the context the interrupt will be run in.
- *
- * IRQC_IS_HARDIRQ - interrupt runs in hardirq context
- * IRQC_IS_NESTED - interrupt runs in a nested threaded context
- */
- enum {
- IRQC_IS_HARDIRQ = 0,
- IRQC_IS_NESTED,
- };
- typedef irqreturn_t (*irq_handler_t)(int, void *);
- /**
- * struct irqaction - per interrupt action descriptor
- * @handler: interrupt handler function
- * @name: name of the device
- * @dev_id: cookie to identify the device
- * @percpu_dev_id: cookie to identify the device
- * @next: pointer to the next irqaction for shared interrupts
- * @irq: interrupt number
- * @flags: flags (see IRQF_* above)
- * @thread_fn: interrupt handler function for threaded interrupts
- * @thread: thread pointer for threaded interrupts
- * @secondary: pointer to secondary irqaction (force threading)
- * @thread_flags: flags related to @thread
- * @thread_mask: bitmask for keeping track of @thread activity
- * @dir: pointer to the proc/irq/NN/name entry
- */
- struct irqaction {
- irq_handler_t handler;
- void *dev_id;
- void __percpu *percpu_dev_id;
- struct irqaction *next;
- irq_handler_t thread_fn;
- struct task_struct *thread;
- struct irqaction *secondary;
- unsigned int irq;
- unsigned int flags;
- unsigned long thread_flags;
- unsigned long thread_mask;
- const char *name;
- struct proc_dir_entry *dir;
- } ____cacheline_internodealigned_in_smp;
- extern irqreturn_t no_action(int cpl, void *dev_id);
- /*
- * If a (PCI) device interrupt is not connected we set dev->irq to
- * IRQ_NOTCONNECTED. This causes request_irq() to fail with -ENOTCONN, so we
- * can distingiush that case from other error returns.
- *
- * 0x80000000 is guaranteed to be outside the available range of interrupts
- * and easy to distinguish from other possible incorrect values.
- */
- #define IRQ_NOTCONNECTED (1U << 31)
- extern int __must_check
- request_threaded_irq(unsigned int irq, irq_handler_t handler,
- irq_handler_t thread_fn,
- unsigned long flags, const char *name, void *dev);
- /**
- * request_irq - Add a handler for an interrupt line
- * @irq: The interrupt line to allocate
- * @handler: Function to be called when the IRQ occurs.
- * Primary handler for threaded interrupts
- * If NULL, the default primary handler is installed
- * @flags: Handling flags
- * @name: Name of the device generating this interrupt
- * @dev: A cookie passed to the handler function
- *
- * This call allocates an interrupt and establishes a handler; see
- * the documentation for request_threaded_irq() for details.
- */
- static inline int __must_check
- request_irq(unsigned int irq, irq_handler_t handler, unsigned long flags,
- const char *name, void *dev)
- {
- return request_threaded_irq(irq, handler, NULL, flags, name, dev);
- }
- extern int __must_check
- request_any_context_irq(unsigned int irq, irq_handler_t handler,
- unsigned long flags, const char *name, void *dev_id);
- extern int __must_check
- __request_percpu_irq(unsigned int irq, irq_handler_t handler,
- unsigned long flags, const char *devname,
- void __percpu *percpu_dev_id);
- extern int __must_check
- request_nmi(unsigned int irq, irq_handler_t handler, unsigned long flags,
- const char *name, void *dev);
- static inline int __must_check
- request_percpu_irq(unsigned int irq, irq_handler_t handler,
- const char *devname, void __percpu *percpu_dev_id)
- {
- return __request_percpu_irq(irq, handler, 0,
- devname, percpu_dev_id);
- }
- extern int __must_check
- request_percpu_nmi(unsigned int irq, irq_handler_t handler,
- const char *devname, void __percpu *dev);
- extern const void *free_irq(unsigned int, void *);
- extern void free_percpu_irq(unsigned int, void __percpu *);
- extern const void *free_nmi(unsigned int irq, void *dev_id);
- extern void free_percpu_nmi(unsigned int irq, void __percpu *percpu_dev_id);
- struct device;
- extern int __must_check
- devm_request_threaded_irq(struct device *dev, unsigned int irq,
- irq_handler_t handler, irq_handler_t thread_fn,
- unsigned long irqflags, const char *devname,
- void *dev_id);
- static inline int __must_check
- devm_request_irq(struct device *dev, unsigned int irq, irq_handler_t handler,
- unsigned long irqflags, const char *devname, void *dev_id)
- {
- return devm_request_threaded_irq(dev, irq, handler, NULL, irqflags,
- devname, dev_id);
- }
- extern int __must_check
- devm_request_any_context_irq(struct device *dev, unsigned int irq,
- irq_handler_t handler, unsigned long irqflags,
- const char *devname, void *dev_id);
- extern void devm_free_irq(struct device *dev, unsigned int irq, void *dev_id);
- bool irq_has_action(unsigned int irq);
- extern void disable_irq_nosync(unsigned int irq);
- extern bool disable_hardirq(unsigned int irq);
- extern void disable_irq(unsigned int irq);
- extern void disable_percpu_irq(unsigned int irq);
- extern void enable_irq(unsigned int irq);
- extern void enable_percpu_irq(unsigned int irq, unsigned int type);
- extern bool irq_percpu_is_enabled(unsigned int irq);
- extern void irq_wake_thread(unsigned int irq, void *dev_id);
- extern void disable_nmi_nosync(unsigned int irq);
- extern void disable_percpu_nmi(unsigned int irq);
- extern void enable_nmi(unsigned int irq);
- extern void enable_percpu_nmi(unsigned int irq, unsigned int type);
- extern int prepare_percpu_nmi(unsigned int irq);
- extern void teardown_percpu_nmi(unsigned int irq);
- extern int irq_inject_interrupt(unsigned int irq);
- /* The following three functions are for the core kernel use only. */
- extern void suspend_device_irqs(void);
- extern void resume_device_irqs(void);
- extern void rearm_wake_irq(unsigned int irq);
- /**
- * struct irq_affinity_notify - context for notification of IRQ affinity changes
- * @irq: Interrupt to which notification applies
- * @kref: Reference count, for internal use
- * @work: Work item, for internal use
- * @notify: Function to be called on change. This will be
- * called in process context.
- * @release: Function to be called on release. This will be
- * called in process context. Once registered, the
- * structure must only be freed when this function is
- * called or later.
- */
- struct irq_affinity_notify {
- unsigned int irq;
- struct kref kref;
- struct work_struct work;
- void (*notify)(struct irq_affinity_notify *, const cpumask_t *mask);
- void (*release)(struct kref *ref);
- };
- #define IRQ_AFFINITY_MAX_SETS 4
- /**
- * struct irq_affinity - Description for automatic irq affinity assignements
- * @pre_vectors: Don't apply affinity to @pre_vectors at beginning of
- * the MSI(-X) vector space
- * @post_vectors: Don't apply affinity to @post_vectors at end of
- * the MSI(-X) vector space
- * @nr_sets: The number of interrupt sets for which affinity
- * spreading is required
- * @set_size: Array holding the size of each interrupt set
- * @calc_sets: Callback for calculating the number and size
- * of interrupt sets
- * @priv: Private data for usage by @calc_sets, usually a
- * pointer to driver/device specific data.
- */
- struct irq_affinity {
- unsigned int pre_vectors;
- unsigned int post_vectors;
- unsigned int nr_sets;
- unsigned int set_size[IRQ_AFFINITY_MAX_SETS];
- void (*calc_sets)(struct irq_affinity *, unsigned int nvecs);
- void *priv;
- };
- /**
- * struct irq_affinity_desc - Interrupt affinity descriptor
- * @mask: cpumask to hold the affinity assignment
- * @is_managed: 1 if the interrupt is managed internally
- */
- struct irq_affinity_desc {
- struct cpumask mask;
- unsigned int is_managed : 1;
- };
- #if defined(CONFIG_SMP)
- extern cpumask_var_t irq_default_affinity;
- extern int irq_set_affinity(unsigned int irq, const struct cpumask *cpumask);
- extern int irq_force_affinity(unsigned int irq, const struct cpumask *cpumask);
- extern int irq_can_set_affinity(unsigned int irq);
- extern int irq_select_affinity(unsigned int irq);
- extern int __irq_apply_affinity_hint(unsigned int irq, const struct cpumask *m,
- bool setaffinity);
- /**
- * irq_update_affinity_hint - Update the affinity hint
- * @irq: Interrupt to update
- * @m: cpumask pointer (NULL to clear the hint)
- *
- * Updates the affinity hint, but does not change the affinity of the interrupt.
- */
- static inline int
- irq_update_affinity_hint(unsigned int irq, const struct cpumask *m)
- {
- return __irq_apply_affinity_hint(irq, m, false);
- }
- /**
- * irq_set_affinity_and_hint - Update the affinity hint and apply the provided
- * cpumask to the interrupt
- * @irq: Interrupt to update
- * @m: cpumask pointer (NULL to clear the hint)
- *
- * Updates the affinity hint and if @m is not NULL it applies it as the
- * affinity of that interrupt.
- */
- static inline int
- irq_set_affinity_and_hint(unsigned int irq, const struct cpumask *m)
- {
- return __irq_apply_affinity_hint(irq, m, true);
- }
- /*
- * Deprecated. Use irq_update_affinity_hint() or irq_set_affinity_and_hint()
- * instead.
- */
- static inline int irq_set_affinity_hint(unsigned int irq, const struct cpumask *m)
- {
- return irq_set_affinity_and_hint(irq, m);
- }
- extern int irq_update_affinity_desc(unsigned int irq,
- struct irq_affinity_desc *affinity);
- extern int
- irq_set_affinity_notifier(unsigned int irq, struct irq_affinity_notify *notify);
- struct irq_affinity_desc *
- irq_create_affinity_masks(unsigned int nvec, struct irq_affinity *affd);
- unsigned int irq_calc_affinity_vectors(unsigned int minvec, unsigned int maxvec,
- const struct irq_affinity *affd);
- #else /* CONFIG_SMP */
- static inline int irq_set_affinity(unsigned int irq, const struct cpumask *m)
- {
- return -EINVAL;
- }
- static inline int irq_force_affinity(unsigned int irq, const struct cpumask *cpumask)
- {
- return 0;
- }
- static inline int irq_can_set_affinity(unsigned int irq)
- {
- return 0;
- }
- static inline int irq_select_affinity(unsigned int irq) { return 0; }
- static inline int irq_update_affinity_hint(unsigned int irq,
- const struct cpumask *m)
- {
- return -EINVAL;
- }
- static inline int irq_set_affinity_and_hint(unsigned int irq,
- const struct cpumask *m)
- {
- return -EINVAL;
- }
- static inline int irq_set_affinity_hint(unsigned int irq,
- const struct cpumask *m)
- {
- return -EINVAL;
- }
- static inline int irq_update_affinity_desc(unsigned int irq,
- struct irq_affinity_desc *affinity)
- {
- return -EINVAL;
- }
- static inline int
- irq_set_affinity_notifier(unsigned int irq, struct irq_affinity_notify *notify)
- {
- return 0;
- }
- static inline struct irq_affinity_desc *
- irq_create_affinity_masks(unsigned int nvec, struct irq_affinity *affd)
- {
- return NULL;
- }
- static inline unsigned int
- irq_calc_affinity_vectors(unsigned int minvec, unsigned int maxvec,
- const struct irq_affinity *affd)
- {
- return maxvec;
- }
- #endif /* CONFIG_SMP */
- /*
- * Special lockdep variants of irq disabling/enabling.
- * These should be used for locking constructs that
- * know that a particular irq context which is disabled,
- * and which is the only irq-context user of a lock,
- * that it's safe to take the lock in the irq-disabled
- * section without disabling hardirqs.
- *
- * On !CONFIG_LOCKDEP they are equivalent to the normal
- * irq disable/enable methods.
- */
- static inline void disable_irq_nosync_lockdep(unsigned int irq)
- {
- disable_irq_nosync(irq);
- #ifdef CONFIG_LOCKDEP
- local_irq_disable();
- #endif
- }
- static inline void disable_irq_nosync_lockdep_irqsave(unsigned int irq, unsigned long *flags)
- {
- disable_irq_nosync(irq);
- #ifdef CONFIG_LOCKDEP
- local_irq_save(*flags);
- #endif
- }
- static inline void disable_irq_lockdep(unsigned int irq)
- {
- disable_irq(irq);
- #ifdef CONFIG_LOCKDEP
- local_irq_disable();
- #endif
- }
- static inline void enable_irq_lockdep(unsigned int irq)
- {
- #ifdef CONFIG_LOCKDEP
- local_irq_enable();
- #endif
- enable_irq(irq);
- }
- static inline void enable_irq_lockdep_irqrestore(unsigned int irq, unsigned long *flags)
- {
- #ifdef CONFIG_LOCKDEP
- local_irq_restore(*flags);
- #endif
- enable_irq(irq);
- }
- /* IRQ wakeup (PM) control: */
- extern int irq_set_irq_wake(unsigned int irq, unsigned int on);
- static inline int enable_irq_wake(unsigned int irq)
- {
- return irq_set_irq_wake(irq, 1);
- }
- static inline int disable_irq_wake(unsigned int irq)
- {
- return irq_set_irq_wake(irq, 0);
- }
- /*
- * irq_get_irqchip_state/irq_set_irqchip_state specific flags
- */
- enum irqchip_irq_state {
- IRQCHIP_STATE_PENDING, /* Is interrupt pending? */
- IRQCHIP_STATE_ACTIVE, /* Is interrupt in progress? */
- IRQCHIP_STATE_MASKED, /* Is interrupt masked? */
- IRQCHIP_STATE_LINE_LEVEL, /* Is IRQ line high? */
- };
- extern int irq_get_irqchip_state(unsigned int irq, enum irqchip_irq_state which,
- bool *state);
- extern int irq_set_irqchip_state(unsigned int irq, enum irqchip_irq_state which,
- bool state);
- #ifdef CONFIG_IRQ_FORCED_THREADING
- # ifdef CONFIG_PREEMPT_RT
- # define force_irqthreads() (true)
- # else
- DECLARE_STATIC_KEY_FALSE(force_irqthreads_key);
- # define force_irqthreads() (static_branch_unlikely(&force_irqthreads_key))
- # endif
- #else
- #define force_irqthreads() (false)
- #endif
- #ifndef local_softirq_pending
- #ifndef local_softirq_pending_ref
- #define local_softirq_pending_ref irq_stat.__softirq_pending
- #endif
- #define local_softirq_pending() (__this_cpu_read(local_softirq_pending_ref))
- #define set_softirq_pending(x) (__this_cpu_write(local_softirq_pending_ref, (x)))
- #define or_softirq_pending(x) (__this_cpu_or(local_softirq_pending_ref, (x)))
- /**
- * __cpu_softirq_pending() - Checks to see if softirq is pending on a cpu
- *
- * This helper is inherently racy, as we're accessing per-cpu data w/o locks.
- * But peeking at the flag can still be useful when deciding where to place a
- * task.
- */
- static inline u32 __cpu_softirq_pending(int cpu)
- {
- return (u32)per_cpu(local_softirq_pending_ref, cpu);
- }
- #endif /* local_softirq_pending */
- /* Some architectures might implement lazy enabling/disabling of
- * interrupts. In some cases, such as stop_machine, we might want
- * to ensure that after a local_irq_disable(), interrupts have
- * really been disabled in hardware. Such architectures need to
- * implement the following hook.
- */
- #ifndef hard_irq_disable
- #define hard_irq_disable() do { } while(0)
- #endif
- /* PLEASE, avoid to allocate new softirqs, if you need not _really_ high
- frequency threaded job scheduling. For almost all the purposes
- tasklets are more than enough. F.e. all serial device BHs et
- al. should be converted to tasklets, not to softirqs.
- */
- enum
- {
- HI_SOFTIRQ=0,
- TIMER_SOFTIRQ,
- NET_TX_SOFTIRQ,
- NET_RX_SOFTIRQ,
- BLOCK_SOFTIRQ,
- IRQ_POLL_SOFTIRQ,
- TASKLET_SOFTIRQ,
- SCHED_SOFTIRQ,
- HRTIMER_SOFTIRQ,
- RCU_SOFTIRQ, /* Preferable RCU should always be the last softirq */
- NR_SOFTIRQS
- };
- /*
- * The following vectors can be safely ignored after ksoftirqd is parked:
- *
- * _ RCU:
- * 1) rcutree_migrate_callbacks() migrates the queue.
- * 2) rcu_report_dead() reports the final quiescent states.
- *
- * _ IRQ_POLL: irq_poll_cpu_dead() migrates the queue
- *
- * _ (HR)TIMER_SOFTIRQ: (hr)timers_dead_cpu() migrates the queue
- */
- #define SOFTIRQ_HOTPLUG_SAFE_MASK (BIT(TIMER_SOFTIRQ) | BIT(IRQ_POLL_SOFTIRQ) |\
- BIT(HRTIMER_SOFTIRQ) | BIT(RCU_SOFTIRQ))
- /* Softirq's where the handling might be long: */
- #define LONG_SOFTIRQ_MASK (BIT(NET_TX_SOFTIRQ) | \
- BIT(NET_RX_SOFTIRQ) | \
- BIT(BLOCK_SOFTIRQ) | \
- BIT(IRQ_POLL_SOFTIRQ))
- /* map softirq index to softirq name. update 'softirq_to_name' in
- * kernel/softirq.c when adding a new softirq.
- */
- extern const char * const softirq_to_name[NR_SOFTIRQS];
- /* softirq mask and active fields moved to irq_cpustat_t in
- * asm/hardirq.h to get better cache usage. KAO
- */
- struct softirq_action
- {
- void (*action)(struct softirq_action *);
- };
- asmlinkage void do_softirq(void);
- asmlinkage void __do_softirq(void);
- #ifdef CONFIG_PREEMPT_RT
- extern void do_softirq_post_smp_call_flush(unsigned int was_pending);
- #else
- static inline void do_softirq_post_smp_call_flush(unsigned int unused)
- {
- do_softirq();
- }
- #endif
- extern void open_softirq(int nr, void (*action)(struct softirq_action *));
- extern void softirq_init(void);
- extern void __raise_softirq_irqoff(unsigned int nr);
- extern void raise_softirq_irqoff(unsigned int nr);
- extern void raise_softirq(unsigned int nr);
- DECLARE_PER_CPU(struct task_struct *, ksoftirqd);
- #ifdef CONFIG_RT_SOFTIRQ_AWARE_SCHED
- DECLARE_PER_CPU(u32, active_softirqs);
- #endif
- static inline struct task_struct *this_cpu_ksoftirqd(void)
- {
- return this_cpu_read(ksoftirqd);
- }
- /* Tasklets --- multithreaded analogue of BHs.
- This API is deprecated. Please consider using threaded IRQs instead:
- https://lore.kernel.org/lkml/[email protected]
- Main feature differing them of generic softirqs: tasklet
- is running only on one CPU simultaneously.
- Main feature differing them of BHs: different tasklets
- may be run simultaneously on different CPUs.
- Properties:
- * If tasklet_schedule() is called, then tasklet is guaranteed
- to be executed on some cpu at least once after this.
- * If the tasklet is already scheduled, but its execution is still not
- started, it will be executed only once.
- * If this tasklet is already running on another CPU (or schedule is called
- from tasklet itself), it is rescheduled for later.
- * Tasklet is strictly serialized wrt itself, but not
- wrt another tasklets. If client needs some intertask synchronization,
- he makes it with spinlocks.
- */
- struct tasklet_struct
- {
- struct tasklet_struct *next;
- unsigned long state;
- atomic_t count;
- bool use_callback;
- union {
- void (*func)(unsigned long data);
- void (*callback)(struct tasklet_struct *t);
- };
- unsigned long data;
- };
- #define DECLARE_TASKLET(name, _callback) \
- struct tasklet_struct name = { \
- .count = ATOMIC_INIT(0), \
- .callback = _callback, \
- .use_callback = true, \
- }
- #define DECLARE_TASKLET_DISABLED(name, _callback) \
- struct tasklet_struct name = { \
- .count = ATOMIC_INIT(1), \
- .callback = _callback, \
- .use_callback = true, \
- }
- #define from_tasklet(var, callback_tasklet, tasklet_fieldname) \
- container_of(callback_tasklet, typeof(*var), tasklet_fieldname)
- #define DECLARE_TASKLET_OLD(name, _func) \
- struct tasklet_struct name = { \
- .count = ATOMIC_INIT(0), \
- .func = _func, \
- }
- #define DECLARE_TASKLET_DISABLED_OLD(name, _func) \
- struct tasklet_struct name = { \
- .count = ATOMIC_INIT(1), \
- .func = _func, \
- }
- enum
- {
- TASKLET_STATE_SCHED, /* Tasklet is scheduled for execution */
- TASKLET_STATE_RUN /* Tasklet is running (SMP only) */
- };
- #if defined(CONFIG_SMP) || defined(CONFIG_PREEMPT_RT)
- static inline int tasklet_trylock(struct tasklet_struct *t)
- {
- return !test_and_set_bit(TASKLET_STATE_RUN, &(t)->state);
- }
- void tasklet_unlock(struct tasklet_struct *t);
- void tasklet_unlock_wait(struct tasklet_struct *t);
- void tasklet_unlock_spin_wait(struct tasklet_struct *t);
- #else
- static inline int tasklet_trylock(struct tasklet_struct *t) { return 1; }
- static inline void tasklet_unlock(struct tasklet_struct *t) { }
- static inline void tasklet_unlock_wait(struct tasklet_struct *t) { }
- static inline void tasklet_unlock_spin_wait(struct tasklet_struct *t) { }
- #endif
- extern void __tasklet_schedule(struct tasklet_struct *t);
- static inline void tasklet_schedule(struct tasklet_struct *t)
- {
- if (!test_and_set_bit(TASKLET_STATE_SCHED, &t->state))
- __tasklet_schedule(t);
- }
- extern void __tasklet_hi_schedule(struct tasklet_struct *t);
- static inline void tasklet_hi_schedule(struct tasklet_struct *t)
- {
- if (!test_and_set_bit(TASKLET_STATE_SCHED, &t->state))
- __tasklet_hi_schedule(t);
- }
- static inline void tasklet_disable_nosync(struct tasklet_struct *t)
- {
- atomic_inc(&t->count);
- smp_mb__after_atomic();
- }
- /*
- * Do not use in new code. Disabling tasklets from atomic contexts is
- * error prone and should be avoided.
- */
- static inline void tasklet_disable_in_atomic(struct tasklet_struct *t)
- {
- tasklet_disable_nosync(t);
- tasklet_unlock_spin_wait(t);
- smp_mb();
- }
- static inline void tasklet_disable(struct tasklet_struct *t)
- {
- tasklet_disable_nosync(t);
- tasklet_unlock_wait(t);
- smp_mb();
- }
- static inline void tasklet_enable(struct tasklet_struct *t)
- {
- smp_mb__before_atomic();
- atomic_dec(&t->count);
- }
- extern void tasklet_kill(struct tasklet_struct *t);
- extern void tasklet_init(struct tasklet_struct *t,
- void (*func)(unsigned long), unsigned long data);
- extern void tasklet_setup(struct tasklet_struct *t,
- void (*callback)(struct tasklet_struct *));
- /*
- * Autoprobing for irqs:
- *
- * probe_irq_on() and probe_irq_off() provide robust primitives
- * for accurate IRQ probing during kernel initialization. They are
- * reasonably simple to use, are not "fooled" by spurious interrupts,
- * and, unlike other attempts at IRQ probing, they do not get hung on
- * stuck interrupts (such as unused PS2 mouse interfaces on ASUS boards).
- *
- * For reasonably foolproof probing, use them as follows:
- *
- * 1. clear and/or mask the device's internal interrupt.
- * 2. sti();
- * 3. irqs = probe_irq_on(); // "take over" all unassigned idle IRQs
- * 4. enable the device and cause it to trigger an interrupt.
- * 5. wait for the device to interrupt, using non-intrusive polling or a delay.
- * 6. irq = probe_irq_off(irqs); // get IRQ number, 0=none, negative=multiple
- * 7. service the device to clear its pending interrupt.
- * 8. loop again if paranoia is required.
- *
- * probe_irq_on() returns a mask of allocated irq's.
- *
- * probe_irq_off() takes the mask as a parameter,
- * and returns the irq number which occurred,
- * or zero if none occurred, or a negative irq number
- * if more than one irq occurred.
- */
- #if !defined(CONFIG_GENERIC_IRQ_PROBE)
- static inline unsigned long probe_irq_on(void)
- {
- return 0;
- }
- static inline int probe_irq_off(unsigned long val)
- {
- return 0;
- }
- static inline unsigned int probe_irq_mask(unsigned long val)
- {
- return 0;
- }
- #else
- extern unsigned long probe_irq_on(void); /* returns 0 on failure */
- extern int probe_irq_off(unsigned long); /* returns 0 or negative on failure */
- extern unsigned int probe_irq_mask(unsigned long); /* returns mask of ISA interrupts */
- #endif
- #ifdef CONFIG_PROC_FS
- /* Initialize /proc/irq/ */
- extern void init_irq_proc(void);
- #else
- static inline void init_irq_proc(void)
- {
- }
- #endif
- #ifdef CONFIG_IRQ_TIMINGS
- void irq_timings_enable(void);
- void irq_timings_disable(void);
- u64 irq_timings_next_event(u64 now);
- #endif
- struct seq_file;
- int show_interrupts(struct seq_file *p, void *v);
- int arch_show_interrupts(struct seq_file *p, int prec);
- extern int early_irq_init(void);
- extern int arch_probe_nr_irqs(void);
- extern int arch_early_irq_init(void);
- /*
- * We want to know which function is an entrypoint of a hardirq or a softirq.
- */
- #ifndef __irq_entry
- # define __irq_entry __section(".irqentry.text")
- #endif
- #define __softirq_entry __section(".softirqentry.text")
- #endif
|