* - bits 0-7 are the preemption count (max preemption depth: 256)
* - bits 8-15 are the softirq count (max # of softirqs: 256)
*
- * The hardirq count can be overridden per architecture, the default is:
+ * The hardirq count can in theory reach the same as NR_IRQS.
+ * In reality, the number of nested IRQS is limited to the stack
+ * size as well. For archs with over 1000 IRQS it is not practical
+ * to expect that they will all nest. We give a max of 10 bits for
+ * hardirq nesting. An arch may choose to give less than 10 bits.
+ * m68k expects it to be 8.
*
- * - bits 16-27 are the hardirq count (max # of hardirqs: 4096)
- * - ( bit 28 is the PREEMPT_ACTIVE flag. )
+ * - bits 16-25 are the hardirq count (max # of nested hardirqs: 1024)
+ * - bit 26 is the NMI_MASK
+ * - bit 28 is the PREEMPT_ACTIVE flag
*
* PREEMPT_MASK: 0x000000ff
* SOFTIRQ_MASK: 0x0000ff00
- * HARDIRQ_MASK: 0x0fff0000
+ * HARDIRQ_MASK: 0x03ff0000
+ * NMI_MASK: 0x04000000
*/
#define PREEMPT_BITS 8
#define SOFTIRQ_BITS 8
+ #define NMI_BITS 1
- #ifndef HARDIRQ_BITS
- #define HARDIRQ_BITS 12
+ #define MAX_HARDIRQ_BITS 10
- #ifndef MAX_HARDIRQS_PER_CPU
- #define MAX_HARDIRQS_PER_CPU NR_IRQS
+ #ifndef HARDIRQ_BITS
+ # define HARDIRQ_BITS MAX_HARDIRQ_BITS
#endif
- /*
- * The hardirq mask has to be large enough to have space for potentially
- * all IRQ sources in the system nesting on a single CPU.
- */
- #if (1 << HARDIRQ_BITS) < MAX_HARDIRQS_PER_CPU
- # error HARDIRQ_BITS is too low!
- #endif
+ #if HARDIRQ_BITS > MAX_HARDIRQ_BITS
+ #error HARDIRQ_BITS too high!
#endif
#define PREEMPT_SHIFT 0
#define SOFTIRQ_SHIFT (PREEMPT_SHIFT + PREEMPT_BITS)
#define HARDIRQ_SHIFT (SOFTIRQ_SHIFT + SOFTIRQ_BITS)
+ #define NMI_SHIFT (HARDIRQ_SHIFT + HARDIRQ_BITS)
#define __IRQ_MASK(x) ((1UL << (x))-1)
#define PREEMPT_MASK (__IRQ_MASK(PREEMPT_BITS) << PREEMPT_SHIFT)
#define SOFTIRQ_MASK (__IRQ_MASK(SOFTIRQ_BITS) << SOFTIRQ_SHIFT)
#define HARDIRQ_MASK (__IRQ_MASK(HARDIRQ_BITS) << HARDIRQ_SHIFT)
+ #define NMI_MASK (__IRQ_MASK(NMI_BITS) << NMI_SHIFT)
#define PREEMPT_OFFSET (1UL << PREEMPT_SHIFT)
#define SOFTIRQ_OFFSET (1UL << SOFTIRQ_SHIFT)
#define HARDIRQ_OFFSET (1UL << HARDIRQ_SHIFT)
+ #define NMI_OFFSET (1UL << NMI_SHIFT)
- #if PREEMPT_ACTIVE < (1 << (HARDIRQ_SHIFT + HARDIRQ_BITS))
+ #if PREEMPT_ACTIVE < (1 << (NMI_SHIFT + NMI_BITS))
#error PREEMPT_ACTIVE is too low!
#endif
#define hardirq_count() (preempt_count() & HARDIRQ_MASK)
#define softirq_count() (preempt_count() & SOFTIRQ_MASK)
- #define irq_count() (preempt_count() & (HARDIRQ_MASK | SOFTIRQ_MASK))
+ #define irq_count() (preempt_count() & (HARDIRQ_MASK | SOFTIRQ_MASK \
+ | NMI_MASK))
/*
* Are we doing bottom half or hardware interrupt processing?
#define in_softirq() (softirq_count())
#define in_interrupt() (irq_count())
+ /*
+ * Are we in NMI context?
+ */
+ #define in_nmi() (preempt_count() & NMI_MASK)
+
#if defined(CONFIG_PREEMPT)
# define PREEMPT_INATOMIC_BASE kernel_locked()
# define PREEMPT_CHECK_OFFSET 1
# define IRQ_EXIT_OFFSET HARDIRQ_OFFSET
#endif
-#ifdef CONFIG_SMP
+#if defined(CONFIG_SMP) || defined(CONFIG_GENERIC_HARDIRQS)
extern void synchronize_irq(unsigned int irq);
#else
# define synchronize_irq(irq) barrier()
*/
extern void irq_exit(void);
- #define nmi_enter() \
- do { \
- ftrace_nmi_enter(); \
- lockdep_off(); \
- rcu_nmi_enter(); \
- __irq_enter(); \
+ #define nmi_enter() \
+ do { \
+ ftrace_nmi_enter(); \
+ BUG_ON(in_nmi()); \
+ add_preempt_count(NMI_OFFSET + HARDIRQ_OFFSET); \
+ lockdep_off(); \
+ rcu_nmi_enter(); \
+ trace_hardirq_enter(); \
} while (0)
- #define nmi_exit() \
- do { \
- __irq_exit(); \
- rcu_nmi_exit(); \
- lockdep_on(); \
- ftrace_nmi_exit(); \
+ #define nmi_exit() \
+ do { \
+ trace_hardirq_exit(); \
+ rcu_nmi_exit(); \
+ lockdep_on(); \
+ BUG_ON(!in_nmi()); \
+ sub_preempt_count(NMI_OFFSET + HARDIRQ_OFFSET); \
+ ftrace_nmi_exit(); \
} while (0)
#endif /* LINUX_HARDIRQ_H */
#define IRQF_NOBALANCING 0x00000800
#define IRQF_IRQPOLL 0x00001000
+/*
+ * Bits used by threaded handlers:
+ * IRQTF_RUNTHREAD - signals that the interrupt handler thread should run
+ * IRQTF_DIED - handler thread died
+ * IRQTF_WARNED - warning "IRQ_WAKE_THREAD w/o thread_fn" has been printed
+ */
+enum {
+ IRQTF_RUNTHREAD,
+ IRQTF_DIED,
+ IRQTF_WARNED,
+};
+
typedef irqreturn_t (*irq_handler_t)(int, void *);
/**
* @next: pointer to the next irqaction for shared interrupts
* @irq: interrupt number
* @dir: pointer to the proc/irq/NN/name entry
+ * @thread_fn: interupt handler function for threaded interrupts
+ * @thread: thread pointer for threaded interrupts
+ * @thread_flags: flags related to @thread
*/
struct irqaction {
irq_handler_t handler;
struct irqaction *next;
int irq;
struct proc_dir_entry *dir;
+ irq_handler_t thread_fn;
+ struct task_struct *thread;
+ unsigned long thread_flags;
};
extern irqreturn_t no_action(int cpl, void *dev_id);
-extern int __must_check request_irq(unsigned int, irq_handler_t handler,
- unsigned long, const char *, void *);
+
+#ifdef CONFIG_GENERIC_HARDIRQS
+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);
+
+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 void exit_irq_thread(void);
+#else
+
+extern int __must_check
+request_irq(unsigned int irq, irq_handler_t handler, unsigned long flags,
+ const char *name, void *dev);
+
+/*
+ * Special function to avoid ifdeffery in kernel/irq/devres.c which
+ * gets magically built by GENERIC_HARDIRQS=n architectures (sparc,
+ * m68k). I really love these $@%#!* obvious Makefile references:
+ * ../../../kernel/irq/devres.o
+ */
+static inline 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)
+{
+ return request_irq(irq, handler, flags, name, dev);
+}
+
+static inline void exit_irq_thread(void) { }
+#endif
+
extern void free_irq(unsigned int, void *);
struct device;
-extern 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);
+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 void devm_free_irq(struct device *dev, unsigned int irq, void *dev_id);
/*
extern void disable_irq(unsigned int irq);
extern void enable_irq(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);
+ #ifdef CONFIG_PM_SLEEP
+ extern int check_wakeup_irqs(void);
+ #else
+ static inline int check_wakeup_irqs(void) { return 0; }
+ #endif
+
#if defined(CONFIG_SMP) && defined(CONFIG_GENERIC_HARDIRQS)
extern cpumask_var_t irq_default_affinity;
NR_SOFTIRQS
};
+ /* map softirq index to softirq name. update 'softirq_to_name' in
+ * kernel/softirq.c when adding a new softirq.
+ */
+ extern char *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
*/
#include <linux/cache.h>
#include <linux/spinlock.h>
#include <linux/cpumask.h>
+ #include <linux/gfp.h>
#include <linux/irqreturn.h>
#include <linux/irqnr.h>
#include <linux/errno.h>
+ #include <linux/topology.h>
+#include <linux/wait.h>
#include <asm/irq.h>
#include <asm/ptrace.h>
#define IRQ_SPURIOUS_DISABLED 0x00800000 /* IRQ was disabled by the spurious trap */
#define IRQ_MOVE_PCNTXT 0x01000000 /* IRQ migration from process context */
#define IRQ_AFFINITY_SET 0x02000000 /* IRQ affinity was set from userspace*/
+ #define IRQ_SUSPENDED 0x04000000 /* IRQ has gone through suspend sequence */
#ifdef CONFIG_IRQ_PER_CPU
# define CHECK_IRQ_PER_CPU(var) ((var) & IRQ_PER_CPU)
* @affinity: IRQ affinity on SMP
* @cpu: cpu index useful for balancing
* @pending_mask: pending rebalanced interrupts
+ * @threads_active: number of irqaction threads currently running
+ * @wait_for_threads: wait queue for sync_irq to wait for threaded handlers
* @dir: /proc/irq/ procfs entry
* @name: flow handler name for /proc/interrupts output
*/
cpumask_var_t pending_mask;
#endif
#endif
+ atomic_t threads_active;
+ wait_queue_head_t wait_for_threads;
#ifdef CONFIG_PROC_FS
struct proc_dir_entry *dir;
#endif
#include <linux/smp.h>
#include <linux/sem.h>
#include <linux/signal.h>
- #include <linux/fs_struct.h>
+ #include <linux/path.h>
#include <linux/compiler.h>
#include <linux/completion.h>
#include <linux/pid.h>
struct robust_list_head;
struct bio;
struct bts_tracer;
+ struct fs_struct;
/*
* List of flags we want to share for kernel threads,
extern unsigned long nr_active(void);
extern unsigned long nr_iowait(void);
+ extern unsigned long get_parent_ip(unsigned long addr);
+
struct seq_file;
struct cfs_rq;
struct task_group;
extern signed long schedule_timeout_interruptible(signed long timeout);
extern signed long schedule_timeout_killable(signed long timeout);
extern signed long schedule_timeout_uninterruptible(signed long timeout);
+ asmlinkage void __schedule(void);
asmlinkage void schedule(void);
+ extern int mutex_spin_on_owner(struct mutex *lock, struct thread_info *owner);
struct nsproxy;
struct user_namespace;
(mm)->hiwater_vm = (mm)->total_vm; \
} while (0)
- #define get_mm_hiwater_rss(mm) max((mm)->hiwater_rss, get_mm_rss(mm))
- #define get_mm_hiwater_vm(mm) max((mm)->hiwater_vm, (mm)->total_vm)
+ static inline unsigned long get_mm_hiwater_rss(struct mm_struct *mm)
+ {
+ return max(mm->hiwater_rss, get_mm_rss(mm));
+ }
+
+ static inline unsigned long get_mm_hiwater_vm(struct mm_struct *mm)
+ {
+ return max(mm->hiwater_vm, mm->total_vm);
+ }
extern void set_dumpable(struct mm_struct *mm, int value);
extern int get_dumpable(struct mm_struct *mm);
struct list_head cpu_timers[3];
- /* job control IDs */
-
- /*
- * pgrp and session fields are deprecated.
- * use the task_session_Xnr and task_pgrp_Xnr routines below
- */
-
- union {
- pid_t pgrp __deprecated;
- pid_t __pgrp;
- };
-
struct pid *tty_old_pgrp;
- union {
- pid_t session __deprecated;
- pid_t __session;
- };
-
/* boolean value for session group leader */
int leader;
struct rq *busiest, struct sched_domain *sd,
enum cpu_idle_type idle);
void (*pre_schedule) (struct rq *this_rq, struct task_struct *task);
+ int (*needs_post_schedule) (struct rq *this_rq);
void (*post_schedule) (struct rq *this_rq);
void (*task_wake_up) (struct rq *this_rq, struct task_struct *task);
u64 last_wakeup;
u64 avg_overlap;
+ u64 start_runtime;
+ u64 avg_wakeup;
+ u64 nr_migrations;
+
#ifdef CONFIG_SCHEDSTATS
u64 wait_start;
u64 wait_max;
u64 exec_max;
u64 slice_max;
- u64 nr_migrations;
u64 nr_migrations_cold;
u64 nr_failed_migrations_affine;
u64 nr_failed_migrations_running;
#endif
struct list_head tasks;
+ struct plist_node pushable_tasks;
struct mm_struct *mm, *active_mm;
/* ??? */
unsigned int personality;
unsigned did_exec:1;
+ unsigned in_execve:1; /* Tell the LSMs that the process is doing an
+ * execve */
pid_t pid;
pid_t tgid;
/* Protection of (de-)allocation: mm, files, fs, tty, keyrings */
spinlock_t alloc_lock;
+#ifdef CONFIG_GENERIC_HARDIRQS
+ /* IRQ handler threads */
+ struct irqaction *irqaction;
+#endif
+
/* Protection of the PI data structures: */
spinlock_t pi_lock;
int lockdep_depth;
unsigned int lockdep_recursion;
struct held_lock held_locks[MAX_LOCK_DEPTH];
+ gfp_t lockdep_reclaim_gfp;
#endif
/* journalling filesystem info */
int curr_ret_stack;
/* Stack of return addresses for return function tracing */
struct ftrace_ret_stack *ret_stack;
+ /* time stamp for last schedule */
+ unsigned long long ftrace_timestamp;
/*
* Number of functions that haven't been traced
* because of depth overrun.
return rt_prio(p->prio);
}
- static inline void set_task_session(struct task_struct *tsk, pid_t session)
- {
- tsk->signal->__session = session;
- }
-
- static inline void set_task_pgrp(struct task_struct *tsk, pid_t pgrp)
- {
- tsk->signal->__pgrp = pgrp;
- }
-
static inline struct pid *task_pid(struct task_struct *task)
{
return task->pids[PIDTYPE_PID].pid;
return task->group_leader->pids[PIDTYPE_PID].pid;
}
+ /*
+ * Without tasklist or rcu lock it is not safe to dereference
+ * the result of task_pgrp/task_session even if task == current,
+ * we can race with another thread doing sys_setsid/sys_setpgid.
+ */
static inline struct pid *task_pgrp(struct task_struct *task)
{
return task->group_leader->pids[PIDTYPE_PGID].pid;
*
* see also pid_nr() etc in include/linux/pid.h
*/
+ pid_t __task_pid_nr_ns(struct task_struct *task, enum pid_type type,
+ struct pid_namespace *ns);
static inline pid_t task_pid_nr(struct task_struct *tsk)
{
return tsk->pid;
}
- pid_t task_pid_nr_ns(struct task_struct *tsk, struct pid_namespace *ns);
+ static inline pid_t task_pid_nr_ns(struct task_struct *tsk,
+ struct pid_namespace *ns)
+ {
+ return __task_pid_nr_ns(tsk, PIDTYPE_PID, ns);
+ }
static inline pid_t task_pid_vnr(struct task_struct *tsk)
{
- return pid_vnr(task_pid(tsk));
+ return __task_pid_nr_ns(tsk, PIDTYPE_PID, NULL);
}
}
- static inline pid_t task_pgrp_nr(struct task_struct *tsk)
+ static inline pid_t task_pgrp_nr_ns(struct task_struct *tsk,
+ struct pid_namespace *ns)
{
- return tsk->signal->__pgrp;
+ return __task_pid_nr_ns(tsk, PIDTYPE_PGID, ns);
}
- pid_t task_pgrp_nr_ns(struct task_struct *tsk, struct pid_namespace *ns);
-
static inline pid_t task_pgrp_vnr(struct task_struct *tsk)
{
- return pid_vnr(task_pgrp(tsk));
+ return __task_pid_nr_ns(tsk, PIDTYPE_PGID, NULL);
}
- static inline pid_t task_session_nr(struct task_struct *tsk)
+ static inline pid_t task_session_nr_ns(struct task_struct *tsk,
+ struct pid_namespace *ns)
{
- return tsk->signal->__session;
+ return __task_pid_nr_ns(tsk, PIDTYPE_SID, ns);
}
- pid_t task_session_nr_ns(struct task_struct *tsk, struct pid_namespace *ns);
-
static inline pid_t task_session_vnr(struct task_struct *tsk)
{
- return pid_vnr(task_session(tsk));
+ return __task_pid_nr_ns(tsk, PIDTYPE_SID, NULL);
}
+ /* obsolete, do not use */
+ static inline pid_t task_pgrp_nr(struct task_struct *tsk)
+ {
+ return task_pgrp_nr_ns(tsk, &init_pid_ns);
+ }
/**
* pid_alive - check that a task structure is not stale
return set_cpus_allowed_ptr(p, &new_mask);
}
+ /*
+ * Architectures can set this to 1 if they have specified
+ * CONFIG_HAVE_UNSTABLE_SCHED_CLOCK in their arch Kconfig,
+ * but then during bootup it turns out that sched_clock()
+ * is reliable after all:
+ */
+ #ifdef CONFIG_HAVE_UNSTABLE_SCHED_CLOCK
+ extern int sched_clock_stable;
+ #endif
+
extern unsigned long long sched_clock(void);
extern void sched_clock_init(void);
/* Allocate a new mm structure and copy contents from tsk->mm */
extern struct mm_struct *dup_mm(struct task_struct *tsk);
- extern int copy_thread(int, unsigned long, unsigned long, unsigned long, struct task_struct *, struct pt_regs *);
+ extern int copy_thread(unsigned long, unsigned long, unsigned long,
+ struct task_struct *, struct pt_regs *);
extern void flush_thread(void);
extern void exit_thread(void);
#define delay_group_leader(p) \
(thread_group_leader(p) && !thread_group_empty(p))
+ static inline int task_detached(struct task_struct *p)
+ {
+ return p->exit_signal == -1;
+ }
+
/*
* Protects ->fs, ->files, ->mm, ->group_info, ->comm, keyring
* subscriptions and synchronises with wait4(). Also used in procfs. Also
#include <linux/blkdev.h>
#include <linux/task_io_accounting_ops.h>
#include <linux/tracehook.h>
+ #include <linux/fs_struct.h>
#include <linux/init_task.h>
#include <trace/sched.h>
static void exit_mm(struct task_struct * tsk);
- static inline int task_detached(struct task_struct *p)
- {
- return p->exit_signal == -1;
- }
-
static void __unhash_process(struct task_struct *p)
{
nr_threads--;
void __set_special_pids(struct pid *pid)
{
struct task_struct *curr = current->group_leader;
- pid_t nr = pid_nr(pid);
- if (task_session(curr) != pid) {
+ if (task_session(curr) != pid)
change_pid(curr, PIDTYPE_SID, pid);
- set_task_session(curr, nr);
- }
- if (task_pgrp(curr) != pid) {
+
+ if (task_pgrp(curr) != pid)
change_pid(curr, PIDTYPE_PGID, pid);
- set_task_pgrp(curr, nr);
- }
}
static void set_special_pids(struct pid *pid)
void daemonize(const char *name, ...)
{
va_list args;
- struct fs_struct *fs;
sigset_t blocked;
va_start(args, name);
/* Become as one with the init task */
- exit_fs(current); /* current->fs->count--; */
- fs = init_task.fs;
- current->fs = fs;
- atomic_inc(&fs->count);
-
+ daemonize_fs_struct();
exit_files(current);
current->files = init_task.files;
atomic_inc(¤t->files->count);
}
}
- void put_fs_struct(struct fs_struct *fs)
- {
- /* No need to hold fs->lock if we are killing it */
- if (atomic_dec_and_test(&fs->count)) {
- path_put(&fs->root);
- path_put(&fs->pwd);
- kmem_cache_free(fs_cachep, fs);
- }
- }
-
- void exit_fs(struct task_struct *tsk)
- {
- struct fs_struct * fs = tsk->fs;
-
- if (fs) {
- task_lock(tsk);
- tsk->fs = NULL;
- task_unlock(tsk);
- put_fs_struct(fs);
- }
- }
-
- EXPORT_SYMBOL_GPL(exit_fs);
-
#ifdef CONFIG_MM_OWNER
/*
* Task p is exiting and it owned mm, lets find a new owner for it
mmput(mm);
}
- /*
- * Return nonzero if @parent's children should reap themselves.
- *
- * Called with write_lock_irq(&tasklist_lock) held.
- */
- static int ignoring_children(struct task_struct *parent)
- {
- int ret;
- struct sighand_struct *psig = parent->sighand;
- unsigned long flags;
- spin_lock_irqsave(&psig->siglock, flags);
- ret = (psig->action[SIGCHLD-1].sa.sa_handler == SIG_IGN ||
- (psig->action[SIGCHLD-1].sa.sa_flags & SA_NOCLDWAIT));
- spin_unlock_irqrestore(&psig->siglock, flags);
- return ret;
- }
-
- /*
- * Detach all tasks we were using ptrace on.
- * Any that need to be release_task'd are put on the @dead list.
- *
- * Called with write_lock(&tasklist_lock) held.
- */
- static void ptrace_exit(struct task_struct *parent, struct list_head *dead)
- {
- struct task_struct *p, *n;
- int ign = -1;
-
- list_for_each_entry_safe(p, n, &parent->ptraced, ptrace_entry) {
- __ptrace_unlink(p);
-
- if (p->exit_state != EXIT_ZOMBIE)
- continue;
-
- /*
- * If it's a zombie, our attachedness prevented normal
- * parent notification or self-reaping. Do notification
- * now if it would have happened earlier. If it should
- * reap itself, add it to the @dead list. We can't call
- * release_task() here because we already hold tasklist_lock.
- *
- * If it's our own child, there is no notification to do.
- * But if our normal children self-reap, then this child
- * was prevented by ptrace and we must reap it now.
- */
- if (!task_detached(p) && thread_group_empty(p)) {
- if (!same_thread_group(p->real_parent, parent))
- do_notify_parent(p, p->exit_signal);
- else {
- if (ign < 0)
- ign = ignoring_children(parent);
- if (ign)
- p->exit_signal = -1;
- }
- }
-
- if (task_detached(p)) {
- /*
- * Mark it as in the process of being reaped.
- */
- p->exit_state = EXIT_DEAD;
- list_add(&p->ptrace_entry, dead);
- }
- }
- }
-
- /*
- * Finish up exit-time ptrace cleanup.
- *
- * Called without locks.
- */
- static void ptrace_exit_finish(struct task_struct *parent,
- struct list_head *dead)
- {
- struct task_struct *p, *n;
-
- BUG_ON(!list_empty(&parent->ptraced));
-
- list_for_each_entry_safe(p, n, dead, ptrace_entry) {
- list_del_init(&p->ptrace_entry);
- release_task(p);
- }
- }
-
- static void reparent_thread(struct task_struct *p, struct task_struct *father)
- {
- if (p->pdeath_signal)
- /* We already hold the tasklist_lock here. */
- group_send_sig_info(p->pdeath_signal, SEND_SIG_NOINFO, p);
-
- list_move_tail(&p->sibling, &p->real_parent->children);
-
- /* If this is a threaded reparent there is no need to
- * notify anyone anything has happened.
- */
- if (same_thread_group(p->real_parent, father))
- return;
-
- /* We don't want people slaying init. */
- if (!task_detached(p))
- p->exit_signal = SIGCHLD;
-
- /* If we'd notified the old parent about this child's death,
- * also notify the new parent.
- */
- if (!ptrace_reparented(p) &&
- p->exit_state == EXIT_ZOMBIE &&
- !task_detached(p) && thread_group_empty(p))
- do_notify_parent(p, p->exit_signal);
-
- kill_orphaned_pgrp(p, father);
- }
-
/*
* When we die, we re-parent all our children.
* Try to give them to another thread in our thread
return pid_ns->child_reaper;
}
+ /*
+ * Any that need to be release_task'd are put on the @dead list.
+ */
+ static void reparent_thread(struct task_struct *father, struct task_struct *p,
+ struct list_head *dead)
+ {
+ if (p->pdeath_signal)
+ group_send_sig_info(p->pdeath_signal, SEND_SIG_NOINFO, p);
+
+ list_move_tail(&p->sibling, &p->real_parent->children);
+
+ if (task_detached(p))
+ return;
+ /*
+ * If this is a threaded reparent there is no need to
+ * notify anyone anything has happened.
+ */
+ if (same_thread_group(p->real_parent, father))
+ return;
+
+ /* We don't want people slaying init. */
+ p->exit_signal = SIGCHLD;
+
+ /* If it has exited notify the new parent about this child's death. */
+ if (!p->ptrace &&
+ p->exit_state == EXIT_ZOMBIE && thread_group_empty(p)) {
+ do_notify_parent(p, p->exit_signal);
+ if (task_detached(p)) {
+ p->exit_state = EXIT_DEAD;
+ list_move_tail(&p->sibling, dead);
+ }
+ }
+
+ kill_orphaned_pgrp(p, father);
+ }
+
static void forget_original_parent(struct task_struct *father)
{
struct task_struct *p, *n, *reaper;
- LIST_HEAD(ptrace_dead);
+ LIST_HEAD(dead_children);
+
+ exit_ptrace(father);
write_lock_irq(&tasklist_lock);
reaper = find_new_reaper(father);
- /*
- * First clean up ptrace if we were using it.
- */
- ptrace_exit(father, &ptrace_dead);
list_for_each_entry_safe(p, n, &father->children, sibling) {
p->real_parent = reaper;
BUG_ON(p->ptrace);
p->parent = p->real_parent;
}
- reparent_thread(p, father);
+ reparent_thread(father, p, &dead_children);
}
-
write_unlock_irq(&tasklist_lock);
+
BUG_ON(!list_empty(&father->children));
- ptrace_exit_finish(father, &ptrace_dead);
+ list_for_each_entry_safe(p, n, &dead_children, sibling) {
+ list_del_init(&p->sibling);
+ release_task(p);
+ }
}
/*
schedule();
}
+ exit_irq_thread();
+
exit_signals(tsk); /* sets PF_EXITING */
/*
* tsk->flags are checked in the futex code to protect against
return retval;
}
+ static int *task_stopped_code(struct task_struct *p, bool ptrace)
+ {
+ if (ptrace) {
+ if (task_is_stopped_or_traced(p))
+ return &p->exit_code;
+ } else {
+ if (p->signal->flags & SIGNAL_STOP_STOPPED)
+ return &p->signal->group_exit_code;
+ }
+ return NULL;
+ }
+
/*
* Handle sys_wait4 work for one task in state TASK_STOPPED. We hold
* read_lock(&tasklist_lock) on entry. If we return zero, we still hold
int options, struct siginfo __user *infop,
int __user *stat_addr, struct rusage __user *ru)
{
- int retval, exit_code, why;
+ int retval, exit_code, *p_code, why;
uid_t uid = 0; /* unneeded, required by compiler */
pid_t pid;
exit_code = 0;
spin_lock_irq(&p->sighand->siglock);
- if (unlikely(!task_is_stopped_or_traced(p)))
- goto unlock_sig;
-
- if (!ptrace && p->signal->group_stop_count > 0)
- /*
- * A group stop is in progress and this is the group leader.
- * We won't report until all threads have stopped.
- */
+ p_code = task_stopped_code(p, ptrace);
+ if (unlikely(!p_code))
goto unlock_sig;
- exit_code = p->exit_code;
+ exit_code = *p_code;
if (!exit_code)
goto unlock_sig;
if (!unlikely(options & WNOWAIT))
- p->exit_code = 0;
+ *p_code = 0;
/* don't need the RCU readlock here as we're holding a spinlock */
uid = __task_cred(p)->uid;
*/
*notask_error = 0;
- if (task_is_stopped_or_traced(p))
+ if (task_stopped_code(p, ptrace))
return wait_task_stopped(ptrace, p, options,
infop, stat_addr, ru);
pid = find_get_pid(-upid);
} else if (upid == 0) {
type = PIDTYPE_PGID;
- pid = get_pid(task_pgrp(current));
+ pid = get_task_pid(current, PIDTYPE_PGID);
} else /* upid > 0 */ {
type = PIDTYPE_PID;
pid = find_get_pid(upid);
#include <linux/kernel_stat.h>
#include <linux/rculist.h>
#include <linux/hash.h>
+ #include <trace/irq.h>
#include <linux/bootmem.h>
#include "internals.h"
return IRQ_NONE;
}
+static void warn_no_thread(unsigned int irq, struct irqaction *action)
+{
+ if (test_and_set_bit(IRQTF_WARNED, &action->thread_flags))
+ return;
+
+ printk(KERN_WARNING "IRQ %d device %s returned IRQ_WAKE_THREAD "
+ "but no thread function available.", irq, action->name);
+}
+
+ DEFINE_TRACE(irq_handler_entry);
+ DEFINE_TRACE(irq_handler_exit);
+
/**
* handle_IRQ_event - irq action chain handler
* @irq: the interrupt number
local_irq_enable_in_hardirq();
do {
+ trace_irq_handler_entry(irq, action);
ret = action->handler(irq, action->dev_id);
- if (ret == IRQ_HANDLED)
+ trace_irq_handler_exit(irq, action, ret);
+
+ switch (ret) {
+ case IRQ_WAKE_THREAD:
+ /*
+ * Set result to handled so the spurious check
+ * does not trigger.
+ */
+ ret = IRQ_HANDLED;
+
+ /*
+ * Catch drivers which return WAKE_THREAD but
+ * did not set up a thread function
+ */
+ if (unlikely(!action->thread_fn)) {
+ warn_no_thread(irq, action);
+ break;
+ }
+
+ /*
+ * Wake up the handler thread for this
+ * action. In case the thread crashed and was
+ * killed we just pretend that we handled the
+ * interrupt. The hardirq handler above has
+ * disabled the device interrupt, so no irq
+ * storm is lurking.
+ */
+ if (likely(!test_bit(IRQTF_DIED,
+ &action->thread_flags))) {
+ set_bit(IRQTF_RUNTHREAD, &action->thread_flags);
+ wake_up_process(action->thread);
+ }
+
+ /* Fall through to add to randomness */
+ case IRQ_HANDLED:
status |= action->flags;
+ break;
+
+ default:
+ break;
+ }
+
retval |= ret;
action = action->next;
} while (action);
*/
#include <linux/irq.h>
+#include <linux/kthread.h>
#include <linux/module.h>
#include <linux/random.h>
#include <linux/interrupt.h>
#include <linux/slab.h>
+#include <linux/sched.h>
#include "internals.h"
-#if defined(CONFIG_SMP) && defined(CONFIG_GENERIC_HARDIRQS)
-cpumask_var_t irq_default_affinity;
-
/**
* synchronize_irq - wait for pending IRQ handlers (on other CPUs)
* @irq: interrupt number to wait for
/* Oops, that failed? */
} while (status & IRQ_INPROGRESS);
+
+ /*
+ * We made sure that no hardirq handler is running. Now verify
+ * that no threaded handlers are active.
+ */
+ wait_event(desc->wait_for_threads, !atomic_read(&desc->threads_active));
}
EXPORT_SYMBOL(synchronize_irq);
+#ifdef CONFIG_SMP
+cpumask_var_t irq_default_affinity;
+
/**
* irq_can_set_affinity - Check if the affinity of a given irq can be set
* @irq: Interrupt to check
return 1;
}
+static void
+irq_set_thread_affinity(struct irq_desc *desc, const struct cpumask *cpumask)
+{
+ struct irqaction *action = desc->action;
+
+ while (action) {
+ if (action->thread)
+ set_cpus_allowed_ptr(action->thread, cpumask);
+ action = action->next;
+ }
+}
+
/**
* irq_set_affinity - Set the irq affinity of a given irq
* @irq: Interrupt to set affinity
cpumask_copy(desc->affinity, cpumask);
desc->chip->set_affinity(irq, cpumask);
#endif
+ irq_set_thread_affinity(desc, cpumask);
desc->status |= IRQ_AFFINITY_SET;
spin_unlock_irqrestore(&desc->lock, flags);
return 0;
spin_lock_irqsave(&desc->lock, flags);
ret = setup_affinity(irq, desc);
+ if (!ret)
+ irq_set_thread_affinity(desc, desc->affinity);
spin_unlock_irqrestore(&desc->lock, flags);
return ret;
}
#endif
+ void __disable_irq(struct irq_desc *desc, unsigned int irq, bool suspend)
+ {
+ if (suspend) {
+ if (!desc->action || (desc->action->flags & IRQF_TIMER))
+ return;
+ desc->status |= IRQ_SUSPENDED;
+ }
+
+ if (!desc->depth++) {
+ desc->status |= IRQ_DISABLED;
+ desc->chip->disable(irq);
+ }
+ }
+
/**
* disable_irq_nosync - disable an irq without waiting
* @irq: Interrupt to disable
return;
spin_lock_irqsave(&desc->lock, flags);
- if (!desc->depth++) {
- desc->status |= IRQ_DISABLED;
- desc->chip->disable(irq);
- }
+ __disable_irq(desc, irq, false);
spin_unlock_irqrestore(&desc->lock, flags);
}
EXPORT_SYMBOL(disable_irq_nosync);
}
EXPORT_SYMBOL(disable_irq);
- static void __enable_irq(struct irq_desc *desc, unsigned int irq)
+ void __enable_irq(struct irq_desc *desc, unsigned int irq, bool resume)
{
+ if (resume)
+ desc->status &= ~IRQ_SUSPENDED;
+
switch (desc->depth) {
case 0:
+ err_out:
WARN(1, KERN_WARNING "Unbalanced enable for IRQ %d\n", irq);
break;
case 1: {
unsigned int status = desc->status & ~IRQ_DISABLED;
+ if (desc->status & IRQ_SUSPENDED)
+ goto err_out;
/* Prevent probing on this irq: */
desc->status = status | IRQ_NOPROBE;
check_irq_resend(desc, irq);
return;
spin_lock_irqsave(&desc->lock, flags);
- __enable_irq(desc, irq);
+ __enable_irq(desc, irq, false);
spin_unlock_irqrestore(&desc->lock, flags);
}
EXPORT_SYMBOL(enable_irq);
return ret;
}
+static int irq_wait_for_interrupt(struct irqaction *action)
+{
+ while (!kthread_should_stop()) {
+ set_current_state(TASK_INTERRUPTIBLE);
+
+ if (test_and_clear_bit(IRQTF_RUNTHREAD,
+ &action->thread_flags)) {
+ __set_current_state(TASK_RUNNING);
+ return 0;
+ }
+ schedule();
+ }
+ return -1;
+}
+
+/*
+ * Interrupt handler thread
+ */
+static int irq_thread(void *data)
+{
+ struct sched_param param = { .sched_priority = MAX_USER_RT_PRIO/2, };
+ struct irqaction *action = data;
+ struct irq_desc *desc = irq_to_desc(action->irq);
+ int wake;
+
+ sched_setscheduler(current, SCHED_FIFO, ¶m);
+ current->irqaction = action;
+
+ while (!irq_wait_for_interrupt(action)) {
+
+ atomic_inc(&desc->threads_active);
+
+ spin_lock_irq(&desc->lock);
+ if (unlikely(desc->status & IRQ_DISABLED)) {
+ /*
+ * CHECKME: We might need a dedicated
+ * IRQ_THREAD_PENDING flag here, which
+ * retriggers the thread in check_irq_resend()
+ * but AFAICT IRQ_PENDING should be fine as it
+ * retriggers the interrupt itself --- tglx
+ */
+ desc->status |= IRQ_PENDING;
+ spin_unlock_irq(&desc->lock);
+ } else {
+ spin_unlock_irq(&desc->lock);
+
+ action->thread_fn(action->irq, action->dev_id);
+ }
+
+ wake = atomic_dec_and_test(&desc->threads_active);
+
+ if (wake && waitqueue_active(&desc->wait_for_threads))
+ wake_up(&desc->wait_for_threads);
+ }
+
+ /*
+ * Clear irqaction. Otherwise exit_irq_thread() would make
+ * fuzz about an active irq thread going into nirvana.
+ */
+ current->irqaction = NULL;
+ return 0;
+}
+
+/*
+ * Called from do_exit()
+ */
+void exit_irq_thread(void)
+{
+ struct task_struct *tsk = current;
+
+ if (!tsk->irqaction)
+ return;
+
+ printk(KERN_ERR
+ "exiting task \"%s\" (%d) is an active IRQ thread (irq %d)\n",
+ tsk->comm ? tsk->comm : "", tsk->pid, tsk->irqaction->irq);
+
+ /*
+ * Set the THREAD DIED flag to prevent further wakeups of the
+ * soon to be gone threaded handler.
+ */
+ set_bit(IRQTF_DIED, &tsk->irqaction->flags);
+}
+
/*
* Internal function to register an irqaction - typically used to
* allocate special interrupts that are part of the architecture.
rand_initialize_irq(irq);
}
+ /*
+ * Threaded handler ?
+ */
+ if (new->thread_fn) {
+ struct task_struct *t;
+
+ t = kthread_create(irq_thread, new, "irq/%d-%s", irq,
+ new->name);
+ if (IS_ERR(t))
+ return PTR_ERR(t);
+ /*
+ * We keep the reference to the task struct even if
+ * the thread dies to avoid that the interrupt code
+ * references an already freed task_struct.
+ */
+ get_task_struct(t);
+ new->thread = t;
+ wake_up_process(t);
+ }
+
/*
* The following block of code has to be executed atomically
*/
if (!shared) {
irq_chip_set_defaults(desc->chip);
+ init_waitqueue_head(&desc->wait_for_threads);
+
/* Setup the type (level, edge polarity) if configured: */
if (new->flags & IRQF_TRIGGER_MASK) {
ret = __irq_set_trigger(desc, irq,
new->flags & IRQF_TRIGGER_MASK);
- if (ret) {
- spin_unlock_irqrestore(&desc->lock, flags);
- return ret;
- }
+ if (ret)
+ goto out_thread;
} else
compat_irq_chip_set_default_handler(desc);
#if defined(CONFIG_IRQ_PER_CPU)
*/
if (shared && (desc->status & IRQ_SPURIOUS_DISABLED)) {
desc->status &= ~IRQ_SPURIOUS_DISABLED;
- __enable_irq(desc, irq);
+ __enable_irq(desc, irq, false);
}
spin_unlock_irqrestore(&desc->lock, flags);
dump_stack();
}
#endif
+ ret = -EBUSY;
+
+out_thread:
spin_unlock_irqrestore(&desc->lock, flags);
- return -EBUSY;
+ if (new->thread) {
+ struct task_struct *t = new->thread;
+
+ new->thread = NULL;
+ if (likely(!test_bit(IRQTF_DIED, &new->thread_flags)))
+ kthread_stop(t);
+ put_task_struct(t);
+ }
+ return ret;
}
/**
{
struct irq_desc *desc = irq_to_desc(irq);
struct irqaction *action, **action_ptr;
+ struct task_struct *irqthread;
unsigned long flags;
WARN(in_interrupt(), "Trying to free IRQ %d from IRQ context!\n", irq);
else
desc->chip->disable(irq);
}
+
+ irqthread = action->thread;
+ action->thread = NULL;
+
spin_unlock_irqrestore(&desc->lock, flags);
unregister_handler_proc(irq, action);
/* Make sure it's not being used on another CPU: */
synchronize_irq(irq);
+ if (irqthread) {
+ if (!test_bit(IRQTF_DIED, &action->thread_flags))
+ kthread_stop(irqthread);
+ put_task_struct(irqthread);
+ }
+
#ifdef CONFIG_DEBUG_SHIRQ
/*
* It's a shared IRQ -- the driver ought to be prepared for an IRQ
EXPORT_SYMBOL(free_irq);
/**
- * request_irq - allocate an interrupt line
+ * request_threaded_irq - allocate an interrupt line
* @irq: Interrupt line to allocate
- * @handler: Function to be called when the IRQ occurs
+ * @handler: Function to be called when the IRQ occurs.
+ * Primary handler for threaded interrupts
+ * @thread_fn: Function called from the irq handler thread
+ * If NULL, no irq thread is created
* @irqflags: Interrupt type flags
* @devname: An ascii name for the claiming device
* @dev_id: A cookie passed back to the handler function
* raises, you must take care both to initialise your hardware
* and to set up the interrupt handler in the right order.
*
+ * If you want to set up a threaded irq handler for your device
+ * then you need to supply @handler and @thread_fn. @handler ist
+ * still called in hard interrupt context and has to check
+ * whether the interrupt originates from the device. If yes it
+ * needs to disable the interrupt on the device and return
+ * IRQ_THREAD_WAKE which will wake up the handler thread and run
+ * @thread_fn. This split handler design is necessary to support
+ * shared interrupts.
+ *
* Dev_id must be globally unique. Normally the address of the
* device data structure is used as the cookie. Since the handler
* receives this value it makes sense to use it.
* IRQF_TRIGGER_* Specify active edge(s) or level
*
*/
-int request_irq(unsigned int irq, irq_handler_t handler,
- unsigned long irqflags, const char *devname, void *dev_id)
+int request_threaded_irq(unsigned int irq, irq_handler_t handler,
+ irq_handler_t thread_fn, unsigned long irqflags,
+ const char *devname, void *dev_id)
{
struct irqaction *action;
struct irq_desc *desc;
return -ENOMEM;
action->handler = handler;
+ action->thread_fn = thread_fn;
action->flags = irqflags;
action->name = devname;
action->dev_id = dev_id;
#endif
return retval;
}
-EXPORT_SYMBOL(request_irq);
+EXPORT_SYMBOL(request_threaded_irq);
projects / linux-2.6-omap-h63xx.git / commitdiff