plain text document attachment (ktimer-core.patch)
- ktimer subsystem core. It is initialized at bootup and expired by the
timer interrupt, but is otherwise not utilized by any other subsystem yet.
Signed-off-by: Thomas Gleixner <[email protected]>
Signed-off-by: Ingo Molnar <[email protected]>
include/linux/ktime.h | 21 +
include/linux/ktimer.h | 170 +++++++++
init/main.c | 3
kernel/Makefile | 3
kernel/ktimer.c | 905 +++++++++++++++++++++++++++++++++++++++++++++++++
kernel/timer.c | 2
6 files changed, 1103 insertions(+), 1 deletion(-)
Index: linux-2.6.15-rc2-rework/include/linux/ktime.h
===================================================================
--- linux-2.6.15-rc2-rework.orig/include/linux/ktime.h
+++ linux-2.6.15-rc2-rework/include/linux/ktime.h
@@ -307,4 +307,25 @@ static inline u64 ktime_to_ns(const ktim
#endif
+/*
+ * The resolution of the clocks. The resolution value is returned in
+ * the clock_getres() system call to give application programmers an
+ * idea of the (in)accuracy of timers. Timer values are rounded up to
+ * this resolution values.
+ */
+#define KTIME_REALTIME_RES (NSEC_PER_SEC/HZ)
+#define KTIME_MONOTONIC_RES (NSEC_PER_SEC/HZ)
+
+/* Get the monotonic time in ktime_t format: */
+extern ktime_t ktime_get(void);
+
+/* Get the real (wall-) time in ktime_t format: */
+extern ktime_t ktime_get_real(void);
+
+/* Get the monotonic time in timespec format: */
+extern void ktime_get_ts(struct timespec *ts);
+
+/* Get the real (wall-) time in timespec format: */
+#define ktime_get_real_ts(ts) getnstimeofday(ts)
+
#endif
Index: linux-2.6.15-rc2-rework/include/linux/ktimer.h
===================================================================
--- /dev/null
+++ linux-2.6.15-rc2-rework/include/linux/ktimer.h
@@ -0,0 +1,170 @@
+/*
+ * include/linux/ktimer.h
+ *
+ * ktimers - high-precision kernel timers
+ *
+ * Copyright(C) 2005, Thomas Gleixner <[email protected]>
+ * Copyright(C) 2005, Red Hat, Inc., Ingo Molnar
+ *
+ * data type definitions, declarations, prototypes
+ *
+ * Started by: Thomas Gleixner and Ingo Molnar
+ *
+ * For licencing details see kernel-base/COPYING
+ */
+#ifndef _LINUX_KTIMER_H
+#define _LINUX_KTIMER_H
+
+#include <linux/rbtree.h>
+#include <linux/ktime.h>
+#include <linux/init.h>
+#include <linux/list.h>
+#include <linux/wait.h>
+
+/*
+ * Mode arguments of xxx_ktimer functions:
+ */
+enum ktimer_rearm {
+ KTIMER_ABS = 1, /* Time value is absolute */
+ KTIMER_REL, /* Time value is relative to now */
+ KTIMER_INCR, /* Time value is relative to previous expiry time */
+ KTIMER_FORWARD, /* Timer is rearmed with value. Overruns accounted */
+ KTIMER_REARM, /* Timer is rearmed with interval. Overruns accounted */
+ KTIMER_RESTART, /* Timer is restarted with the stored expiry value */
+
+ /*
+ * Expiry must not be checked when the timer is started:
+ * (can be OR-ed with another above mode flag)
+ */
+ KTIMER_NOCHECK = 0x10000,
+ /*
+ * Rounding is required when the time is set up. Thats an
+ * optimization for relative timers as we read current time
+ * in the enqueing code so we do not need to read is twice.
+ */
+ KTIMER_ROUND = 0x20000,
+
+ /* (used internally: no rearming) */
+ KTIMER_NOREARM = 0
+};
+
+/*
+ * Timer states:
+ */
+enum ktimer_state {
+ KTIMER_INACTIVE, /* Timer is inactive */
+ KTIMER_PENDING, /* Timer is pending */
+};
+
+struct ktimer_base;
+
+/**
+ * struct ktimer - the basic ktimer structure
+ *
+ * @node: red black tree node for time ordered insertion
+ * @list: list head for easier access to the time ordered list,
+ * without walking the red black tree.
+ * @expires: the absolute expiry time in the ktimers internal
+ * representation. The time is related to the clock on
+ * which the timer is based.
+ * @expired: the absolute time when the timer expired. Used for
+ * simplifying return path calculations and for debugging
+ * purposes.
+ * @interval: the timer interval for automatic rearming
+ * @overrun: the number of intervals missed when rearming a timer
+ * @state: state of the timer
+ * @function: timer expiry callback function
+ * @data: argument for the callback function
+ * @base: pointer to the timer base (per cpu and per clock)
+ *
+ * The ktimer structure must be initialized by init_ktimer_#CLOCKTYPE()
+ */
+struct ktimer {
+ struct rb_node node;
+ struct list_head list;
+ ktime_t expires;
+ ktime_t expired;
+ ktime_t interval;
+ int overrun;
+ enum ktimer_state state;
+ void (*function)(void *);
+ void *data;
+ struct ktimer_base *base;
+};
+
+/**
+ * struct ktimer_base - the timer base for a specific clock
+ *
+ * @index: clock type index for per_cpu support when moving a timer
+ * to a base on another cpu.
+ * @lock: lock protecting the base and associated timers
+ * @active: red black tree root node for the active timers
+ * @pending: list of pending timers for simple time ordered access
+ * @count: the number of active timers
+ * @resolution: the resolution of the clock, in nanoseconds
+ * @get_time: function to retrieve the current time of the clock
+ * @curr_timer: the timer which is executing a callback right now
+ * @wait: waitqueue to wait for a currently running timer
+ * @name: string identifier of the clock
+ */
+struct ktimer_base {
+ clockid_t index;
+ spinlock_t lock;
+ struct rb_root active;
+ struct list_head pending;
+ int count;
+ unsigned long resolution;
+ ktime_t (*get_time)(void);
+ struct ktimer *curr_timer;
+ wait_queue_head_t wait;
+ char *name;
+};
+
+#define KTIMER_POISON ((void *) 0x00100101)
+
+/* Exported timer functions: */
+
+/* Initialize timers: */
+extern void ktimer_init(struct ktimer *timer);
+extern void ktimer_init_clock(struct ktimer *timer,
+ const clockid_t which_clock);
+
+/* Basic timer operations: */
+extern int ktimer_start(struct ktimer *timer, const ktime_t *tim,
+ const int mode);
+extern int ktimer_restart(struct ktimer *timer, const ktime_t *tim,
+ const int mode);
+extern int ktimer_cancel(struct ktimer *timer);
+extern int ktimer_try_to_cancel(struct ktimer *timer);
+
+/* Query timers: */
+extern ktime_t ktimer_get_remtime(const struct ktimer *timer);
+extern ktime_t ktimer_get_expiry(const struct ktimer *timer, ktime_t *now);
+extern int ktimer_get_res(const clockid_t which_clock, struct timespec *tp);
+extern int ktimer_get_res_clock(const clockid_t which_clock,
+ struct timespec *tp);
+
+static inline int ktimer_active(const struct ktimer *timer)
+{
+ return timer->state != KTIMER_INACTIVE;
+}
+
+/* Convert with rounding based on resolution of timer's clock: */
+extern ktime_t ktimer_round_timeval(const struct ktimer *timer,
+ const struct timeval *tv);
+extern ktime_t ktimer_round_timespec(const struct ktimer *timer,
+ const struct timespec *ts);
+
+#ifdef CONFIG_SMP
+extern void wait_for_ktimer(const struct ktimer *timer);
+#else
+# define wait_for_ktimer(t) do { } while (0)
+#endif
+
+/* Soft interrupt function to run the ktimer queues: */
+extern void ktimer_run_queues(void);
+
+/* Bootup initialization: */
+extern void __init ktimers_init(void);
+
+#endif
Index: linux-2.6.15-rc2-rework/init/main.c
===================================================================
--- linux-2.6.15-rc2-rework.orig/init/main.c
+++ linux-2.6.15-rc2-rework/init/main.c
@@ -47,6 +47,8 @@
#include <linux/rmap.h>
#include <linux/mempolicy.h>
#include <linux/key.h>
+#include <linux/ktimer.h>
+
#include <net/sock.h>
#include <asm/io.h>
@@ -487,6 +489,7 @@ asmlinkage void __init start_kernel(void
init_IRQ();
pidhash_init();
init_timers();
+ ktimers_init();
softirq_init();
time_init();
Index: linux-2.6.15-rc2-rework/kernel/Makefile
===================================================================
--- linux-2.6.15-rc2-rework.orig/kernel/Makefile
+++ linux-2.6.15-rc2-rework/kernel/Makefile
@@ -7,7 +7,8 @@ obj-y = sched.o fork.o exec_domain.o
sysctl.o capability.o ptrace.o timer.o user.o \
signal.o sys.o kmod.o workqueue.o pid.o \
rcupdate.o intermodule.o extable.o params.o posix-timers.o \
- kthread.o wait.o kfifo.o sys_ni.o posix-cpu-timers.o
+ kthread.o wait.o kfifo.o sys_ni.o posix-cpu-timers.o \
+ ktimer.o
obj-$(CONFIG_FUTEX) += futex.o
obj-$(CONFIG_GENERIC_ISA_DMA) += dma.o
Index: linux-2.6.15-rc2-rework/kernel/ktimer.c
===================================================================
--- /dev/null
+++ linux-2.6.15-rc2-rework/kernel/ktimer.c
@@ -0,0 +1,905 @@
+/*
+ * linux/kernel/ktimer.c
+ *
+ * Copyright(C) 2005, Thomas Gleixner <[email protected]>
+ * Copyright(C) 2005, Red Hat, Inc., Ingo Molnar
+ *
+ * High-precision kernel timers
+ *
+ * In contrast to the low-resolution timeout API implemented in
+ * kernel/timer.c, ktimers provide finer resolution and accuracy
+ * depending on system configuration and capabilities.
+ *
+ * These timers are currently used for:
+ * - itimers
+ * - POSIX timers
+ * - nanosleep
+ * - precise in-kernel timing
+ *
+ * Started by: Thomas Gleixner and Ingo Molnar
+ *
+ * Credits:
+ * based on kernel/timer.c
+ *
+ * For licencing details see kernel-base/COPYING
+ */
+
+#include <linux/cpu.h>
+#include <linux/ktimer.h>
+#include <linux/module.h>
+#include <linux/percpu.h>
+#include <linux/notifier.h>
+#include <linux/syscalls.h>
+#include <linux/interrupt.h>
+
+#include <asm/uaccess.h>
+
+/*
+ * The timer bases:
+ */
+
+#define MAX_KTIMER_BASES 2
+
+static DEFINE_PER_CPU(struct ktimer_base, ktimer_bases[MAX_KTIMER_BASES]) =
+{
+ {
+ .index = CLOCK_REALTIME,
+ .name = "Realtime",
+ .get_time = &ktime_get_real,
+ .resolution = KTIME_REALTIME_RES,
+ },
+ {
+ .index = CLOCK_MONOTONIC,
+ .name = "Monotonic",
+ .get_time = &ktime_get,
+ .resolution = KTIME_MONOTONIC_RES,
+ },
+};
+
+/**
+ * ktime_get - get the monotonic time in ktime_t format
+ *
+ * returns the time in ktime_t format
+ */
+ktime_t ktime_get(void)
+{
+ struct timespec now;
+
+ ktime_get_ts(&now);
+
+ return timespec_to_ktime(now);
+}
+
+EXPORT_SYMBOL_GPL(ktime_get);
+
+/**
+ * ktime_get_real - get the real (wall-) time in ktime_t format
+ *
+ * returns the time in ktime_t format
+ */
+ktime_t ktime_get_real(void)
+{
+ struct timespec now;
+
+ getnstimeofday(&now);
+
+ return timespec_to_ktime(now);
+}
+
+EXPORT_SYMBOL_GPL(ktime_get_real);
+
+/**
+ * ktime_get_ts - get the monotonic clock in timespec format
+ *
+ * @ts: pointer to timespec variable
+ *
+ * The function calculates the monotonic clock from the realtime
+ * clock and the wall_to_monotonic offset and stores the result
+ * in normalized timespec format in the variable pointed to by ts.
+ */
+void ktime_get_ts(struct timespec *ts)
+{
+ struct timespec tomono;
+ unsigned long seq;
+
+ do {
+ seq = read_seqbegin(&xtime_lock);
+ getnstimeofday(ts);
+ tomono = wall_to_monotonic;
+
+ } while (read_seqretry(&xtime_lock, seq));
+
+ set_normalized_timespec(ts, ts->tv_sec + tomono.tv_sec,
+ ts->tv_nsec + tomono.tv_nsec);
+}
+
+/*
+ * Functions and macros which are different for UP/SMP systems are kept in a
+ * single place
+ */
+#ifdef CONFIG_SMP
+
+#define set_curr_timer(b, t) (b)->curr_timer = (t)
+#define wake_up_timer_waiters(b) wake_up(&(b)->wait)
+
+/**
+ * wait_for_ktimer - Wait for a running ktimer
+ *
+ * @timer: timer to wait for
+ *
+ * The function waits in case the timers callback function is
+ * currently executed on the waitqueue of the timer base. The
+ * waitqueue is woken up after the timer callback function has
+ * finished execution.
+ */
+void wait_for_ktimer(const struct ktimer *timer)
+{
+ struct ktimer_base *base = timer->base;
+
+ if (base)
+ wait_event(base->wait,
+ base->curr_timer != timer);
+}
+
+/*
+ * We are using hashed locking: holding per_cpu(ktimer_bases)[n].lock
+ * means that all timers which are tied to this base via timer->base are
+ * locked, and the base itself is locked too.
+ *
+ * So __run_timers/migrate_timers can safely modify all timers which could
+ * be found on the lists/queues.
+ *
+ * When the timer's base is locked, and the timer removed from list, it is
+ * possible to set timer->base = NULL and drop the lock: the timer remains
+ * locked.
+ */
+static struct ktimer_base *lock_ktimer_base(const struct ktimer *timer,
+ unsigned long *flags)
+{
+ struct ktimer_base *base;
+
+ for (;;) {
+ base = timer->base;
+ if (likely(base != NULL)) {
+ spin_lock_irqsave(&base->lock, *flags);
+ if (likely(base == timer->base))
+ return base;
+ /* The timer has migrated to another CPU */
+ spin_unlock_irqrestore(&base->lock, *flags);
+ }
+ cpu_relax();
+ }
+}
+
+/*
+ * Switch the timer base to the current CPU when possible.
+ */
+static inline struct ktimer_base *
+switch_ktimer_base(struct ktimer *timer, struct ktimer_base *base)
+{
+ struct ktimer_base *new_base;
+
+ new_base = &__get_cpu_var(ktimer_bases[base->index]);
+
+ if (base != new_base) {
+ /*
+ * We are trying to schedule the timer on the local CPU.
+ * However we can't change timer's base while it is running,
+ * so we keep it on the same CPU. No hassle vs. reprogramming
+ * the event source in the high resolution case. The softirq
+ * code will take care of this when the timer function has
+ * completed. There is no conflict as we hold the lock until
+ * the timer is enqueued.
+ */
+ if (unlikely(base->curr_timer == timer))
+ return base;
+
+ /* See the comment in lock_timer_base() */
+ timer->base = NULL;
+ spin_unlock(&base->lock);
+ spin_lock(&new_base->lock);
+ timer->base = new_base;
+ }
+ return new_base;
+}
+
+/*
+ * Get the timer base unlocked
+ *
+ * Take care of timer->base = NULL in switch_ktimer_base !
+ */
+static inline struct ktimer_base *
+get_ktimer_base_unlocked(const struct ktimer *timer)
+{
+ struct ktimer_base *base;
+
+ while (!(base = timer->base))
+ cpu_relax();
+
+ return base;
+}
+
+#else /* CONFIG_SMP */
+
+#define set_curr_timer(b, t) do { } while (0)
+#define wake_up_timer_waiters(b) do { } while (0)
+
+static inline struct ktimer_base *
+lock_ktimer_base(const struct ktimer *timer, unsigned long *flags)
+{
+ struct ktimer_base *base = timer->base;
+
+ spin_lock_irqsave(&base->lock, *flags);
+
+ return base;
+}
+
+#define switch_ktimer_base(t, b) (b)
+#define get_ktimer_base_unlocked(t) (t)->base
+
+#endif /* !CONFIG_SMP */
+
+/*
+ * Functions for the union type storage format of ktime_t which are
+ * too large for inlining:
+ */
+#if BITS_PER_LONG < 64
+# ifndef CONFIG_KTIME_SCALAR
+/**
+ * ktime_add_ns - Add a scalar nanoseconds value to a ktime_t variable
+ *
+ * @kt: addend
+ * @nsec: the scalar nsec value to add
+ *
+ * Returns the sum of kt and nsec in ktime_t format
+ */
+ktime_t ktime_add_ns(const ktime_t kt, u64 nsec)
+{
+ ktime_t tmp;
+
+ if (likely(nsec < NSEC_PER_SEC)) {
+ tmp.tv64 = nsec;
+ } else {
+ unsigned long rem = do_div(nsec, NSEC_PER_SEC);
+
+ tmp = ktime_set((long)nsec, rem);
+ }
+
+ return ktime_add(kt, tmp);
+}
+
+/**
+ * ktime_modulo - Calculate ktime_t modulo div
+ *
+ * @kt: dividend
+ * @div: divisor
+ *
+ * Return ktime_t modulo div.
+ *
+ * div is less than NSEC_PER_SEC and (NSEC_PER_SEC % div) = 0 !
+ */
+#define ktime_modulo(kt, div) ((unsigned long)(kt).tv.nsec % (div))
+
+#else /* CONFIG_KTIME_SCALAR */
+
+static unsigned long ktime_modulo(const ktime_t kt, const unsigned long div)
+{
+ nsec_t nsec = kt.tv64;
+
+ return do_div(nsec, div);
+}
+
+# endif /* !CONFIG_KTIME_SCALAR */
+#else /* BITS_PER_LONG < 64 */
+# define ktime_modulo(kt, div) (unsigned long)((kt).tv64 % (div))
+#endif /* BITS_PER_LONG >= 64 */
+
+/*
+ * Counterpart to lock_timer_base above.
+ */
+static inline
+void unlock_ktimer_base(const struct ktimer *timer, unsigned long *flags)
+{
+ spin_unlock_irqrestore(&timer->base->lock, *flags);
+}
+
+/**
+ * ktimer_round_timespec - convert timespec to ktime_t with resolution
+ * adjustment
+ *
+ * @timer: ktimer to retrieve the base
+ * @ts: pointer to the timespec value to be converted
+ *
+ * Returns the resolution adjusted ktime_t representation of the
+ * timespec.
+ *
+ * Note: We can access base without locking here, as ktimers can
+ * migrate between CPUs but can not be moved from one clock source to
+ * another. The clock source binding is set at init_ktimer_XXX time.
+ */
+ktime_t ktimer_round_timespec(const struct ktimer *timer,
+ const struct timespec *ts)
+{
+ struct ktimer_base *base = get_ktimer_base_unlocked(timer);
+ long rem = ts->tv_nsec % base->resolution;
+ ktime_t t;
+
+ t = ktime_set(ts->tv_sec, ts->tv_nsec);
+
+ /* Check, if the value has to be rounded */
+ if (rem)
+ t = ktime_add_ns(t, base->resolution - rem);
+
+ return t;
+}
+
+/**
+ * ktimer_round_timeval - convert timeval to ktime_t with resolution
+ * adjustment
+ *
+ * @timer: ktimer to retrieve the base
+ * @tv: pointer to the timeval value to be converted
+ *
+ * Returns the resolution adjusted ktime_t representation of the
+ * timeval.
+ */
+ktime_t ktimer_round_timeval(const struct ktimer *timer,
+ const struct timeval *tv)
+{
+ struct timespec ts;
+
+ ts.tv_sec = tv->tv_sec;
+ ts.tv_nsec = tv->tv_usec * NSEC_PER_USEC;
+
+ return ktimer_round_timespec(timer, &ts);
+}
+
+/*
+ * enqueue_ktimer - internal function to (re)start a timer
+ *
+ * The timer is inserted in expiry order. Insertion into the
+ * red black tree is O(log(n)). Must hold the base lock.
+ */
+static int enqueue_ktimer(struct ktimer *timer, struct ktimer_base *base,
+ const ktime_t *tim, const int mode)
+{
+ struct rb_node **link = &base->active.rb_node;
+ struct list_head *prev = &base->pending;
+ struct rb_node *parent = NULL;
+ struct ktimer *entry;
+ ktime_t now;
+
+ /* Get current time */
+ now = base->get_time();
+
+ /*
+ * Calculate the absolute expiry time based on the
+ * timer expiry mode:
+ */
+ switch (mode & ~(KTIMER_NOCHECK | KTIMER_ROUND)) {
+
+ case KTIMER_ABS:
+ timer->expires = *tim;
+ break;
+
+ case KTIMER_REL:
+ timer->expires = ktime_add(now, *tim);
+ break;
+
+ case KTIMER_INCR:
+ timer->expires = ktime_add(timer->expires, *tim);
+ break;
+
+ case KTIMER_FORWARD:
+ while (timer->expires.tv64 <= now.tv64) {
+ timer->expires = ktime_add(timer->expires, *tim);
+ timer->overrun++;
+ }
+ goto nocheck;
+
+ case KTIMER_REARM:
+ while (timer->expires.tv64 <= now.tv64) {
+ timer->expires = ktime_add(timer->expires,
+ timer->interval);
+ timer->overrun++;
+ }
+ goto nocheck;
+
+ case KTIMER_RESTART:
+ break;
+
+ default:
+ /* illegal mode */
+ BUG();
+ }
+
+ /*
+ * Rounding is requested for one shot timers and the first
+ * event of interval timers. It's done here, so we don't
+ * have to read the current time twice for relative timers.
+ */
+ if (mode & KTIMER_ROUND) {
+ unsigned long rem;
+
+ rem = ktime_modulo(timer->expires, base->resolution);
+ if (rem)
+ timer->expires = ktime_add_ns(timer->expires,
+ base->resolution - rem);
+ }
+
+ /* Expiry time in the past: */
+ if (unlikely(timer->expires.tv64 <= now.tv64)) {
+ timer->expired = now;
+ /* The caller takes care of expiry */
+ if (!(mode & KTIMER_NOCHECK))
+ return -1;
+ }
+ nocheck:
+
+ /*
+ * Find the right place in the rbtree:
+ */
+ while (*link) {
+ parent = *link;
+ entry = rb_entry(parent, struct ktimer, node);
+ /*
+ * We dont care about collisions. Nodes with
+ * the same expiry time stay together.
+ */
+ if (timer->expires.tv64 < entry->expires.tv64)
+ link = &(*link)->rb_left;
+ else {
+ link = &(*link)->rb_right;
+ prev = &entry->list;
+ }
+ }
+
+ /*
+ * Insert the timer to the rbtree and to the sorted list:
+ */
+ rb_link_node(&timer->node, parent, link);
+ rb_insert_color(&timer->node, &base->active);
+ list_add(&timer->list, prev);
+
+ timer->state = KTIMER_PENDING;
+ base->count++;
+
+ return 0;
+}
+
+/*
+ * __remove_ktimer - internal function to remove a timer
+ *
+ * The function also allows automatic rearming for interval timers.
+ * Must hold the base lock.
+ */
+static void
+__remove_ktimer(struct ktimer *timer, struct ktimer_base *base,
+ enum ktimer_rearm rearm)
+{
+ /*
+ * Remove the timer from the sorted list and from the rbtree:
+ */
+ list_del(&timer->list);
+ rb_erase(&timer->node, &base->active);
+ timer->node.rb_parent = KTIMER_POISON;
+
+ timer->state = KTIMER_INACTIVE;
+ base->count--;
+ BUG_ON(base->count < 0);
+
+ /* Auto rearm the timer ? */
+ if (rearm && (timer->interval.tv64 != 0))
+ enqueue_ktimer(timer, base, NULL, KTIMER_REARM);
+}
+
+/*
+ * remove ktimer, called with base lock held
+ */
+static inline int remove_ktimer(struct ktimer *timer, struct ktimer_base *base)
+{
+ if (ktimer_active(timer)) {
+ __remove_ktimer(timer, base, KTIMER_NOREARM);
+ return 1;
+ }
+ return 0;
+}
+
+/*
+ * Internal function to (re)start a timer.
+ */
+static int internal_restart_ktimer(struct ktimer *timer, const ktime_t *tim,
+ const int mode)
+{
+ struct ktimer_base *base, *new_base;
+ unsigned long flags;
+ int ret;
+
+ BUG_ON(!timer->function);
+
+ base = lock_ktimer_base(timer, &flags);
+
+ /* Remove an active timer from the queue */
+ ret = remove_ktimer(timer, base);
+
+ /* Switch the timer base, if necessary */
+ new_base = switch_ktimer_base(timer, base);
+
+ /*
+ * When the new timer setting is already expired,
+ * let the calling code deal with it.
+ */
+ if (enqueue_ktimer(timer, new_base, tim, mode))
+ ret = -1;
+
+ unlock_ktimer_base(timer, &flags);
+
+ return ret;
+}
+
+/**
+ * ktimer_start - start a timer on the current CPU
+ *
+ * @timer: the timer to be added
+ * @tim: expiry time (optional, if not set in the timer)
+ * @mode: timer setup mode
+ *
+ * Returns:
+ * 0 on success
+ * -1 when the new time setting is already expired
+ */
+int ktimer_start(struct ktimer *timer, const ktime_t *tim, const int mode)
+{
+ BUG_ON(ktimer_active(timer));
+
+ return internal_restart_ktimer(timer, tim, mode);
+}
+
+EXPORT_SYMBOL_GPL(ktimer_start);
+
+/**
+ * ktimer_restart - modify a running timer
+ *
+ * @timer: the timer to be modified
+ * @tim: expiry time (required)
+ * @mode: timer setup mode
+ *
+ * Returns:
+ * 0 when the timer was not active
+ * 1 when the timer was active
+ * -1 when the new time setting is already expired
+ */
+int ktimer_restart(struct ktimer *timer, const ktime_t *tim, const int mode)
+{
+ BUG_ON(!tim);
+
+ return internal_restart_ktimer(timer, tim, mode);
+}
+
+EXPORT_SYMBOL_GPL(ktimer_restart);
+
+/**
+ * ktimer_try_to_cancel - try to deactivate a timer
+ *
+ * @timer: ktimer to stop
+ *
+ * Returns:
+ * 0 when the timer was not active
+ * 1 when the timer was active
+ * -1 when the timer is currently excuting the callback function and
+ * can not be stopped
+ */
+int ktimer_try_to_cancel(struct ktimer *timer)
+{
+ struct ktimer_base *base;
+ unsigned long flags;
+ int ret = -1;
+
+ base = lock_ktimer_base(timer, &flags);
+
+ if (base->curr_timer != timer) {
+ ret = remove_ktimer(timer, base);
+ if (ret)
+ timer->expired = base->get_time();
+ }
+
+ unlock_ktimer_base(timer, &flags);
+
+ return ret;
+
+}
+
+EXPORT_SYMBOL_GPL(ktimer_try_to_cancel);
+
+/**
+ * ktimer_cancel - cancel a timer and wait for the handler to finish.
+ *
+ * @timer: the timer to be cancelled
+ *
+ * Returns:
+ * 0 when the timer was not active
+ * 1 when the timer was active
+ */
+int ktimer_cancel(struct ktimer *timer)
+{
+ for (;;) {
+ int ret = ktimer_try_to_cancel(timer);
+
+ if (ret >= 0)
+ return ret;
+ wait_for_ktimer(timer);
+ }
+}
+
+EXPORT_SYMBOL_GPL(ktimer_cancel);
+
+/**
+ * ktimer_get_remtime - get remaining time for the timer
+ *
+ * @timer: the timer to read
+ *
+ * Returns the delta between the expiry time and now, which can be
+ * less than zero.
+ */
+ktime_t ktimer_get_remtime(const struct ktimer *timer)
+{
+ struct ktimer_base *base;
+ unsigned long flags;
+ ktime_t rem;
+
+ base = lock_ktimer_base(timer, &flags);
+ rem = ktime_sub(timer->expires, base->get_time());
+ unlock_ktimer_base(timer, &flags);
+
+ return rem;
+}
+
+/**
+ * ktimer_get_expiry - get expiry time for the timer
+ *
+ * @timer: the timer to read
+ * @now: if != NULL then store current base->time into it
+ */
+ktime_t ktimer_get_expiry(const struct ktimer *timer, ktime_t *now)
+{
+ struct ktimer_base *base;
+ unsigned long flags;
+ ktime_t expiry;
+
+ base = lock_ktimer_base(timer, &flags);
+ expiry = timer->expires;
+ if (now)
+ *now = base->get_time();
+ unlock_ktimer_base(timer, &flags);
+
+ return expiry;
+}
+
+/*
+ * Functions related to clock sources
+ */
+
+static inline void ktimer_common_init(struct ktimer *timer)
+{
+ memset(timer, 0, sizeof(struct ktimer));
+ timer->node.rb_parent = KTIMER_POISON;
+}
+
+/**
+ * ktimer_init - initialize a timer to the monotonic clock
+ *
+ * @timer: the timer to be initialized
+ */
+void ktimer_init(struct ktimer *timer)
+{
+ struct ktimer_base *bases;
+
+ ktimer_common_init(timer);
+ bases = per_cpu(ktimer_bases, raw_smp_processor_id());
+ timer->base = &bases[CLOCK_MONOTONIC];
+}
+
+EXPORT_SYMBOL_GPL(ktimer_init);
+
+/**
+ * ktimer_init_clock - initialize a timer to the given clock
+ *
+ * @timer: the timer to be initialized
+ * @clock_id: the clock to be used
+ */
+void ktimer_init_clock(struct ktimer *timer, const clockid_t clock_id)
+{
+ struct ktimer_base *bases;
+
+ ktimer_common_init(timer);
+ bases = per_cpu(ktimer_bases, raw_smp_processor_id());
+ timer->base = &bases[clock_id];
+}
+
+EXPORT_SYMBOL_GPL(ktimer_init_clock);
+
+/**
+ * ktimer_get_res - get the monotonic timer resolution
+ *
+ * @which_clock: unused parameter for compability with the posix timer code
+ * @tp: pointer to timespec variable to store the resolution
+ *
+ * Store the resolution of clock monotonic in the variable pointed to
+ * by tp.
+ */
+int ktimer_get_res(const clockid_t which_clock, struct timespec *tp)
+{
+ struct ktimer_base *bases;
+
+ tp->tv_sec = 0;
+ bases = per_cpu(ktimer_bases, raw_smp_processor_id());
+ tp->tv_nsec = bases[CLOCK_MONOTONIC].resolution;
+
+ return 0;
+}
+
+/**
+ * ktimer_get_res_clock - get the timer resolution for a clock
+ *
+ * @which_clock: which clock to query
+ * @tp: pointer to timespec variable to store the resolution
+ *
+ * Store the resolution of clock realtime in the variable pointed to
+ * by tp.
+ */
+int ktimer_get_res_clock(const clockid_t which_clock, struct timespec *tp)
+{
+ struct ktimer_base *bases;
+
+ tp->tv_sec = 0;
+ bases = per_cpu(ktimer_bases, raw_smp_processor_id());
+ tp->tv_nsec = bases[which_clock].resolution;
+
+ return 0;
+}
+
+/*
+ * Expire the per base ktimer-queue:
+ */
+static inline void run_ktimer_queue(struct ktimer_base *base)
+{
+ ktime_t now = base->get_time();
+
+ spin_lock_irq(&base->lock);
+
+ while (!list_empty(&base->pending)) {
+ struct ktimer *timer;
+ void (*fn)(void *);
+ void *data;
+
+ timer = list_entry(base->pending.next, struct ktimer, list);
+ if (now.tv64 <= timer->expires.tv64)
+ break;
+
+ timer->expired = now;
+ fn = timer->function;
+ data = timer->data;
+ set_curr_timer(base, timer);
+ __remove_ktimer(timer, base, KTIMER_REARM);
+ spin_unlock_irq(&base->lock);
+
+ fn(data);
+
+ spin_lock_irq(&base->lock);
+ set_curr_timer(base, NULL);
+ }
+ spin_unlock_irq(&base->lock);
+
+ wake_up_timer_waiters(base);
+}
+
+/*
+ * Called from timer softirq every jiffy, expire ktimers:
+ */
+void ktimer_run_queues(void)
+{
+ struct ktimer_base *base = __get_cpu_var(ktimer_bases);
+ int i;
+
+ for (i = 0; i < MAX_KTIMER_BASES; i++)
+ run_ktimer_queue(&base[i]);
+}
+
+/*
+ * Functions related to boot-time initialization:
+ */
+static void __devinit init_ktimers_cpu(int cpu)
+{
+ struct ktimer_base *base = per_cpu(ktimer_bases, cpu);
+ int i;
+
+ for (i = 0; i < MAX_KTIMER_BASES; i++) {
+ spin_lock_init(&base->lock);
+ INIT_LIST_HEAD(&base->pending);
+ init_waitqueue_head(&base->wait);
+ base++;
+ }
+}
+
+#ifdef CONFIG_HOTPLUG_CPU
+
+static void migrate_ktimer_list(struct ktimer_base *old_base,
+ struct ktimer_base *new_base)
+{
+ struct ktimer *timer;
+ struct rb_node *node;
+
+ while ((node = rb_first(&old_base->active))) {
+ timer = rb_entry(node, struct ktimer, node);
+ remove_ktimer(timer, old_base);
+ timer->base = new_base;
+ enqueue_ktimer(timer, new_base, NULL, KTIMER_RESTART);
+ }
+}
+
+static void migrate_ktimers(int cpu)
+{
+ struct ktimer_base *old_base, *new_base;
+ int i;
+
+ BUG_ON(cpu_online(cpu));
+ old_base = per_cpu(ktimer_bases, cpu);
+ new_base = get_cpu_var(ktimer_bases);
+
+ local_irq_disable();
+
+ for (i = 0; i < MAX_KTIMER_BASES; i++) {
+
+ spin_lock(&new_base->lock);
+ spin_lock(&old_base->lock);
+
+ BUG_ON(old_base->curr_timer);
+
+ migrate_ktimer_list(old_base, new_base);
+
+ spin_unlock(&old_base->lock);
+ spin_unlock(&new_base->lock);
+ old_base++;
+ new_base++;
+ }
+
+ local_irq_enable();
+ put_cpu_var(ktimer_bases);
+}
+#endif /* CONFIG_HOTPLUG_CPU */
+
+static int __devinit ktimer_cpu_notify(struct notifier_block *self,
+ unsigned long action, void *hcpu)
+{
+ long cpu = (long)hcpu;
+
+ switch(action) {
+
+ case CPU_UP_PREPARE:
+ init_ktimers_cpu(cpu);
+ break;
+
+#ifdef CONFIG_HOTPLUG_CPU
+ case CPU_DEAD:
+ migrate_ktimers(cpu);
+ break;
+#endif
+
+ default:
+ break;
+ }
+
+ return NOTIFY_OK;
+}
+
+static struct notifier_block __devinitdata ktimers_nb = {
+ .notifier_call = ktimer_cpu_notify,
+};
+
+void __init ktimers_init(void)
+{
+ ktimer_cpu_notify(&ktimers_nb, (unsigned long)CPU_UP_PREPARE,
+ (void *)(long)smp_processor_id());
+ register_cpu_notifier(&ktimers_nb);
+}
+
Index: linux-2.6.15-rc2-rework/kernel/timer.c
===================================================================
--- linux-2.6.15-rc2-rework.orig/kernel/timer.c
+++ linux-2.6.15-rc2-rework/kernel/timer.c
@@ -30,6 +30,7 @@
#include <linux/thread_info.h>
#include <linux/time.h>
#include <linux/jiffies.h>
+#include <linux/ktimer.h>
#include <linux/posix-timers.h>
#include <linux/cpu.h>
#include <linux/syscalls.h>
@@ -857,6 +858,7 @@ static void run_timer_softirq(struct sof
{
tvec_base_t *base = &__get_cpu_var(tvec_bases);
+ ktimer_run_queues();
if (time_after_eq(jiffies, base->timer_jiffies))
__run_timers(base);
}
--
-
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