--- /dev/null
+/* LGPL (v2.1 or any later version) - see LICENSE file for details */
+#include <ccan/timer/timer.h>
+#include <ccan/array_size/array_size.h>
+#include <ccan/ilog/ilog.h>
+#include <ccan/likely/likely.h>
+#include <stdlib.h>
+#include <stdio.h>
+
+#define PER_LEVEL (1ULL << TIMER_LEVEL_BITS)
+
+struct timer_level {
+ struct list_head list[PER_LEVEL];
+};
+
+static uint64_t time_to_grains(struct timespec ts)
+{
+ return ts.tv_sec * ((uint64_t)1000000000 / TIMER_GRANULARITY)
+ + (ts.tv_nsec / TIMER_GRANULARITY);
+}
+
+static struct timespec grains_to_time(uint64_t grains)
+{
+ struct timespec ts;
+
+ ts.tv_sec = grains / (1000000000 / TIMER_GRANULARITY);
+ ts.tv_nsec = (grains % (1000000000 / TIMER_GRANULARITY))
+ * TIMER_GRANULARITY;
+ return ts;
+}
+
+void timers_init(struct timers *timers, struct timespec start)
+{
+ unsigned int i;
+
+ list_head_init(&timers->far);
+ timers->base = time_to_grains(start);
+ for (i = 0; i < ARRAY_SIZE(timers->level); i++)
+ timers->level[i] = NULL;
+}
+
+static void timer_add_raw(struct timers *timers, struct timer *t)
+{
+ struct list_head *l;
+ uint64_t diff;
+ unsigned int level;
+
+ /* Level depends how far away it is. */
+ diff = t->time - timers->base;
+ level = ilog64(diff / 2) / TIMER_LEVEL_BITS;
+
+ if (!timers->level[level])
+ l = &timers->far;
+ else {
+ int off = (t->time >> (level*TIMER_LEVEL_BITS)) & (PER_LEVEL-1);
+ l = &timers->level[level]->list[off];
+ }
+
+ list_add_tail(l, &t->list);
+}
+
+void timer_add(struct timers *timers, struct timer *t, struct timespec when)
+{
+ t->time = time_to_grains(when);
+
+ /* Added in the past? Treat it as imminent. */
+ if (t->time < timers->base)
+ t->time = timers->base;
+
+ timer_add_raw(timers, t);
+}
+
+/* FIXME: inline */
+void timer_del(struct timers *timers, struct timer *t)
+{
+ list_del(&t->list);
+}
+
+static void timers_far_get(struct timers *timers,
+ struct list_head *list,
+ uint64_t when)
+{
+ struct timer *i, *next;
+
+ list_for_each_safe(&timers->far, i, next, list) {
+ if (i->time <= when) {
+ list_del_from(&timers->far, &i->list);
+ list_add_tail(list, &i->list);
+ }
+ }
+}
+
+static void add_level(struct timers *timers, unsigned int level)
+{
+ struct timer_level *l;
+ struct timer *t;
+ unsigned int i;
+ struct list_head from_far;
+
+ l = malloc(sizeof(*l));
+ if (!l)
+ return;
+
+ for (i = 0; i < ARRAY_SIZE(l->list); i++)
+ list_head_init(&l->list[i]);
+ timers->level[level] = l;
+
+ list_head_init(&from_far);
+ timers_far_get(timers, &from_far,
+ timers->base + (1ULL << ((level+1)*TIMER_LEVEL_BITS)) - 1);
+
+ while ((t = list_pop(&from_far, struct timer, list)) != NULL)
+ timer_add_raw(timers, t);
+}
+
+/* Take timers from level and distribute them down one. */
+static void cascade(struct timers *timers, unsigned int level)
+{
+ struct timer *i;
+ struct list_head from_far, *list;
+
+ if (level == ARRAY_SIZE(timers->level) || !timers->level[level]) {
+ list_head_init(&from_far);
+ timers_far_get(timers, &from_far,
+ timers->base
+ + (1ULL << (level*TIMER_LEVEL_BITS))-1);
+ list = &from_far;
+ if (level != ARRAY_SIZE(timers->level))
+ add_level(timers, level);
+ } else {
+ unsigned src;
+
+ src = (timers->base >> (level * TIMER_LEVEL_BITS)) % PER_LEVEL;
+ if (src == 0)
+ cascade(timers, level + 1);
+ list = &timers->level[level]->list[src];
+ }
+
+ while ((i = list_pop(list, struct timer, list)) != NULL) {
+ unsigned dst;
+
+ assert(i->time >= timers->base);
+ assert(i->time < (timers->base
+ + (1ULL << ((level+1)*TIMER_LEVEL_BITS))));
+
+ dst = (i->time >> ((level-1)*TIMER_LEVEL_BITS)) % PER_LEVEL;
+ list_add_tail(&timers->level[level-1]->list[dst], &i->list);
+ }
+}
+
+static const struct timer *find_first(const struct list_head *list,
+ const struct timer *prev)
+{
+ struct timer *t;
+
+ list_for_each(list, t, list) {
+ if (!prev || t->time < prev->time)
+ prev = t;
+ }
+ return prev;
+}
+
+static struct timer *get_first(const struct timers *timers)
+{
+ unsigned int level = 0, i, off;
+ bool need_next;
+ uint64_t base = timers->base;
+ const struct timer *found = NULL;
+ struct list_head *h;
+
+next:
+ if (!timers->level[level])
+ return (struct timer *)find_first(&timers->far, NULL);
+
+ need_next = false;
+ off = base % PER_LEVEL;
+ for (i = 0; i < PER_LEVEL; i++) {
+ h = &timers->level[level]->list[(i+off) % PER_LEVEL];
+
+ if (!list_empty(h))
+ break;
+
+ /* We haven't cascaded yet, so if we wrap, we'll need to
+ * check next level, too. */
+ if (i + off == PER_LEVEL)
+ need_next = true;
+ }
+ if (i == PER_LEVEL) {
+ level++;
+ base >>= TIMER_LEVEL_BITS;
+ goto next;
+ }
+
+ /* Level 0 is exact, so they're all the same. */
+ if (level == 0)
+ found = list_top(h, struct timer, list);
+ else
+ found = find_first(h, NULL);
+
+ if (need_next) {
+ if (!timers->level[level+1]) {
+ found = find_first(&timers->far, found);
+ } else {
+ base >>= TIMER_LEVEL_BITS;
+ off = base % PER_LEVEL;
+ h = &timers->level[level+1]->list[off];
+ found = find_first(h, found);
+ }
+ }
+
+ return (struct timer *)found;
+}
+
+bool timer_earliest(const struct timers *timers, struct timespec *first)
+{
+ struct timer *found = get_first(timers);
+
+ if (!found)
+ return false;
+ *first = grains_to_time(found->time);
+ return true;
+}
+
+/* Assume no timers before 'time', cascade down and update base time. */
+static void timer_fast_forward(struct timers *timers, uint64_t time)
+{
+ unsigned int level, changed;
+ int need_level = -1;
+ struct list_head list;
+ struct timer *i;
+
+ /* How many bits changed between base and time?
+ * Each time we wrap, we need to empty buckets from above. */
+ if (time == timers->base)
+ return;
+
+ changed = ilog64_nz(time ^ timers->base);
+ level = (changed - 1) / TIMER_LEVEL_BITS;
+
+ /* Buckets always empty downwards, so we could cascade manually,
+ * but it's rarely very many so we just remove and re-add */
+ list_head_init(&list);
+
+ do {
+ if (!timers->level[level]) {
+ /* We need any which belong on this level. */
+ timers_far_get(timers, &list,
+ timers->base
+ + (1ULL << ((level+1)*TIMER_LEVEL_BITS))-1);
+ need_level = level;
+ } else {
+ unsigned src;
+
+ /* Get all timers from this bucket. */
+ src = (time >> (level * TIMER_LEVEL_BITS)) % PER_LEVEL;
+ list_append_list(&list,
+ &timers->level[level]->list[src]);
+ }
+ } while (level--);
+
+ /* Did we hit the last level? If so, add. */
+ if (need_level != -1)
+ add_level(timers, need_level);
+
+ /* Fast-forward the time, and re-add everyone. */
+ timers->base = time;
+ while ((i = list_pop(&list, struct timer, list)) != NULL)
+ timer_add_raw(timers, i);
+}
+
+/* Fills list of expired timers. */
+void timers_expire(struct timers *timers,
+ struct timespec expire,
+ struct list_head *list)
+{
+ uint64_t now = time_to_grains(expire);
+ unsigned int off;
+ const struct timer *first;
+
+ assert(now >= timers->base);
+
+ list_head_init(list);
+
+ if (!timers->level[0]) {
+ if (list_empty(&timers->far))
+ return;
+ add_level(timers, 0);
+ }
+
+ while ((first = get_first(timers)) != NULL) {
+ assert(first->time >= timers->base);
+ if (first->time > now) {
+ timer_fast_forward(timers, now);
+ break;
+ }
+
+ timer_fast_forward(timers, first->time);
+ off = timers->base % PER_LEVEL;
+
+ list_append_list(list, &timers->level[0]->list[off]);
+ if (timers->base == now)
+ break;
+ }
+}
+
+static bool timer_list_check(const struct list_head *l,
+ uint64_t min, uint64_t max,
+ const char *abortstr)
+{
+ const struct timer *t;
+
+ if (!list_check(l, abortstr))
+ return false;
+
+ list_for_each(l, t, list) {
+ if (t->time < min || t->time > max) {
+ if (abortstr) {
+ fprintf(stderr,
+ "%s: timer %p %llu not %llu-%llu\n",
+ abortstr, t, t->time, min, max);
+ abort();
+ }
+ return false;
+ }
+ }
+ return true;
+}
+
+struct timers *timers_check(const struct timers *timers, const char *abortstr)
+{
+ unsigned int l, i, off;
+ uint64_t base;
+
+ l = 0;
+ if (!timers->level[0])
+ goto past_levels;
+
+ /* First level is simple. */
+ off = timers->base % PER_LEVEL;
+ for (i = 0; i < PER_LEVEL; i++) {
+ struct list_head *h;
+
+ h = &timers->level[l]->list[(i+off) % PER_LEVEL];
+ if (!timer_list_check(h, timers->base + i, timers->base + i,
+ abortstr))
+ return NULL;
+ }
+
+ /* For other levels, "current" bucket has been emptied, and may contain
+ * entries for the current + level_size bucket. */
+ for (l = 1; timers->level[l] && l < PER_LEVEL; l++) {
+ uint64_t per_bucket = 1ULL << (TIMER_LEVEL_BITS * l);
+
+ off = ((timers->base >> (l*TIMER_LEVEL_BITS)) % PER_LEVEL);
+ /* We start at *next* bucket. */
+ base = (timers->base & ~(per_bucket - 1)) + per_bucket;
+
+ for (i = 1; i <= PER_LEVEL; i++) {
+ struct list_head *h;
+
+ h = &timers->level[l]->list[(i+off) % PER_LEVEL];
+ if (!timer_list_check(h, base, base + per_bucket - 1,
+ abortstr))
+ return NULL;
+ base += per_bucket;
+ }
+ }
+
+past_levels:
+ base = (timers->base & ~((1ULL << (TIMER_LEVEL_BITS * l)) - 1))
+ + (1ULL << (TIMER_LEVEL_BITS * l)) - 1;
+ if (!timer_list_check(&timers->far, base, -1ULL, abortstr))
+ return NULL;
+
+ return (struct timers *)timers;
+}
+
+//#ifdef CCAN_TIMER_DEBUG
+void timers_dump(const struct timers *timers, FILE *fp)
+{
+ unsigned int l, i;
+ uint64_t min, max, num;
+ struct timer *t;
+
+ if (!fp)
+ fp = stderr;
+
+ fprintf(fp, "Base: %llu\n", timers->base);
+
+ for (l = 0; timers->level[l] && l < ARRAY_SIZE(timers->level); l++) {
+ fprintf(fp, "Level %i (+%llu):\n",
+ l, (uint64_t)1 << (TIMER_LEVEL_BITS * l));
+ for (i = 0; i < (1 << TIMER_LEVEL_BITS); i++) {
+
+ if (list_empty(&timers->level[l]->list[i]))
+ continue;
+ min = -1ULL;
+ max = 0;
+ num = 0;
+ list_for_each(&timers->level[l]->list[i], t, list) {
+ if (t->time < min)
+ min = t->time;
+ if (t->time > max)
+ max = t->time;
+ num++;
+ }
+ fprintf(stderr, " %llu (+%llu-+%llu)\n",
+ num, min - timers->base, max - timers->base);
+ }
+ }
+
+ min = -1ULL;
+ max = 0;
+ num = 0;
+ list_for_each(&timers->far, t, list) {
+ if (t->time < min)
+ min = t->time;
+ if (t->time > max)
+ max = t->time;
+ num++;
+ }
+ fprintf(stderr, "Far: %llu (%llu-%llu)\n", num, min, max);
+}
+//#endif
+
+void timers_cleanup(struct timers *timers)
+{
+ unsigned int l;
+
+ for (l = 0; l < ARRAY_SIZE(timers->level); l++)
+ free(timers->level[l]);
+}
projects / ccan / blobdiff