1 // SPDX-License-Identifier: GPL-2.0
3 * random utiility code, for bcache but in theory not specific to bcache
5 * Copyright 2010, 2011 Kent Overstreet <kent.overstreet@gmail.com>
6 * Copyright 2012 Google, Inc.
10 #include <linux/blkdev.h>
11 #include <linux/console.h>
12 #include <linux/ctype.h>
13 #include <linux/debugfs.h>
14 #include <linux/freezer.h>
15 #include <linux/kthread.h>
16 #include <linux/log2.h>
17 #include <linux/math64.h>
18 #include <linux/percpu.h>
19 #include <linux/preempt.h>
20 #include <linux/random.h>
21 #include <linux/seq_file.h>
22 #include <linux/string.h>
23 #include <linux/types.h>
24 #include <linux/sched/clock.h>
25 #include <linux/mean_and_variance.h>
27 #include "eytzinger.h"
30 static const char si_units[] = "?kMGTPEZY";
32 /* string_get_size units: */
33 static const char *const units_2[] = {
34 "B", "KiB", "MiB", "GiB", "TiB", "PiB", "EiB", "ZiB", "YiB"
36 static const char *const units_10[] = {
37 "B", "kB", "MB", "GB", "TB", "PB", "EB", "ZB", "YB"
40 static int parse_u64(const char *cp, u64 *res)
42 const char *start = cp;
52 if (v > U64_MAX - (*cp - '0'))
56 } while (isdigit(*cp));
62 static int bch2_pow(u64 n, u64 p, u64 *res)
67 if (*res > div_u64(U64_MAX, n))
74 static int parse_unit_suffix(const char *cp, u64 *res)
76 const char *start = cp;
84 for (u = 1; u < strlen(si_units); u++)
85 if (*cp == si_units[u]) {
90 for (u = 0; u < ARRAY_SIZE(units_2); u++)
91 if (!strncmp(cp, units_2[u], strlen(units_2[u]))) {
92 cp += strlen(units_2[u]);
96 for (u = 0; u < ARRAY_SIZE(units_10); u++)
97 if (!strncmp(cp, units_10[u], strlen(units_10[u]))) {
98 cp += strlen(units_10[u]);
106 ret = bch2_pow(base, u, res);
113 #define parse_or_ret(cp, _f) \
121 static int __bch2_strtou64_h(const char *cp, u64 *res)
123 const char *start = cp;
124 u64 v = 0, b, f_n = 0, f_d = 1;
127 parse_or_ret(cp, parse_u64(cp, &v));
131 ret = parse_u64(cp, &f_n);
136 ret = bch2_pow(10, ret, &f_d);
141 parse_or_ret(cp, parse_unit_suffix(cp, &b));
143 if (v > div_u64(U64_MAX, b))
147 if (f_n > div_u64(U64_MAX, b))
150 f_n = div_u64(f_n * b, f_d);
159 static int __bch2_strtoh(const char *cp, u64 *res,
160 u64 t_max, bool t_signed)
162 bool positive = *cp != '-';
165 if (*cp == '+' || *cp == '-')
168 parse_or_ret(cp, __bch2_strtou64_h(cp, &v));
191 #define STRTO_H(name, type) \
192 int bch2_ ## name ## _h(const char *cp, type *res) \
195 int ret = __bch2_strtoh(cp, &v, ANYSINT_MAX(type), \
196 ANYSINT_MAX(type) != ((type) ~0ULL)); \
201 STRTO_H(strtoint, int)
202 STRTO_H(strtouint, unsigned int)
203 STRTO_H(strtoll, long long)
204 STRTO_H(strtoull, unsigned long long)
205 STRTO_H(strtou64, u64)
207 u64 bch2_read_flag_list(char *opt, const char * const list[])
210 char *p, *s, *d = kstrdup(opt, GFP_KERNEL);
217 while ((p = strsep(&s, ","))) {
218 int flag = match_string(list, -1, p);
233 bool bch2_is_zero(const void *_p, size_t n)
238 for (i = 0; i < n; i++)
244 void bch2_prt_u64_binary(struct printbuf *out, u64 v, unsigned nr_bits)
247 prt_char(out, '0' + ((v >> --nr_bits) & 1));
250 void bch2_print_string_as_lines(const char *prefix, const char *lines)
255 printk("%s (null)\n", prefix);
261 p = strchrnul(lines, '\n');
262 printk("%s%.*s\n", prefix, (int) (p - lines), lines);
270 int bch2_save_backtrace(bch_stacktrace *stack, struct task_struct *task)
272 #ifdef CONFIG_STACKTRACE
273 unsigned nr_entries = 0;
277 ret = darray_make_room(stack, 32);
281 if (!down_read_trylock(&task->signal->exec_update_lock))
285 nr_entries = stack_trace_save_tsk(task, stack->data, stack->size, 0);
286 } while (nr_entries == stack->size &&
287 !(ret = darray_make_room(stack, stack->size * 2)));
289 stack->nr = nr_entries;
290 up_read(&task->signal->exec_update_lock);
298 void bch2_prt_backtrace(struct printbuf *out, bch_stacktrace *stack)
302 darray_for_each(*stack, i) {
303 prt_printf(out, "[<0>] %pB", (void *) *i);
308 int bch2_prt_task_backtrace(struct printbuf *out, struct task_struct *task)
310 bch_stacktrace stack = { 0 };
311 int ret = bch2_save_backtrace(&stack, task);
313 bch2_prt_backtrace(out, &stack);
320 #ifndef CONFIG_BCACHEFS_NO_LATENCY_ACCT
321 static void bch2_quantiles_update(struct bch2_quantiles *q, u64 v)
325 while (i < ARRAY_SIZE(q->entries)) {
326 struct bch2_quantile_entry *e = q->entries + i;
328 if (unlikely(!e->step)) {
330 e->step = max_t(unsigned, v / 2, 1024);
331 } else if (e->m > v) {
332 e->m = e->m >= e->step
335 } else if (e->m < v) {
336 e->m = e->m + e->step > e->m
341 if ((e->m > v ? e->m - v : v - e->m) < e->step)
342 e->step = max_t(unsigned, e->step / 2, 1);
347 i = eytzinger0_child(i, v > e->m);
351 static inline void bch2_time_stats_update_one(struct bch2_time_stats *stats,
356 if (time_after64(end, start)) {
357 duration = end - start;
358 mean_and_variance_update(&stats->duration_stats, duration);
359 mean_and_variance_weighted_update(&stats->duration_stats_weighted, duration);
360 stats->max_duration = max(stats->max_duration, duration);
361 stats->min_duration = min(stats->min_duration, duration);
362 bch2_quantiles_update(&stats->quantiles, duration);
365 if (time_after64(end, stats->last_event)) {
366 freq = end - stats->last_event;
367 mean_and_variance_update(&stats->freq_stats, freq);
368 mean_and_variance_weighted_update(&stats->freq_stats_weighted, freq);
369 stats->max_freq = max(stats->max_freq, freq);
370 stats->min_freq = min(stats->min_freq, freq);
371 stats->last_event = end;
375 static noinline void bch2_time_stats_clear_buffer(struct bch2_time_stats *stats,
376 struct bch2_time_stat_buffer *b)
378 struct bch2_time_stat_buffer_entry *i;
381 spin_lock_irqsave(&stats->lock, flags);
383 i < b->entries + ARRAY_SIZE(b->entries);
385 bch2_time_stats_update_one(stats, i->start, i->end);
386 spin_unlock_irqrestore(&stats->lock, flags);
391 void __bch2_time_stats_update(struct bch2_time_stats *stats, u64 start, u64 end)
395 WARN_RATELIMIT(!stats->min_duration || !stats->min_freq,
396 "time_stats: min_duration = %llu, min_freq = %llu",
397 stats->min_duration, stats->min_freq);
399 if (!stats->buffer) {
400 spin_lock_irqsave(&stats->lock, flags);
401 bch2_time_stats_update_one(stats, start, end);
403 if (mean_and_variance_weighted_get_mean(stats->freq_stats_weighted) < 32 &&
404 stats->duration_stats.n > 1024)
406 alloc_percpu_gfp(struct bch2_time_stat_buffer,
408 spin_unlock_irqrestore(&stats->lock, flags);
410 struct bch2_time_stat_buffer *b;
413 b = this_cpu_ptr(stats->buffer);
415 BUG_ON(b->nr >= ARRAY_SIZE(b->entries));
416 b->entries[b->nr++] = (struct bch2_time_stat_buffer_entry) {
421 if (unlikely(b->nr == ARRAY_SIZE(b->entries)))
422 bch2_time_stats_clear_buffer(stats, b);
428 static const struct time_unit {
433 { "us", NSEC_PER_USEC },
434 { "ms", NSEC_PER_MSEC },
435 { "s", NSEC_PER_SEC },
436 { "m", (u64) NSEC_PER_SEC * 60},
437 { "h", (u64) NSEC_PER_SEC * 3600},
441 static const struct time_unit *pick_time_units(u64 ns)
443 const struct time_unit *u;
446 u + 1 < time_units + ARRAY_SIZE(time_units) &&
447 ns >= u[1].nsecs << 1;
454 void bch2_pr_time_units(struct printbuf *out, u64 ns)
456 const struct time_unit *u = pick_time_units(ns);
458 prt_printf(out, "%llu %s", div_u64(ns, u->nsecs), u->name);
461 static void bch2_pr_time_units_aligned(struct printbuf *out, u64 ns)
463 const struct time_unit *u = pick_time_units(ns);
465 prt_printf(out, "%llu ", div64_u64(ns, u->nsecs));
467 prt_printf(out, "%s", u->name);
472 void bch2_prt_date_seconds(struct printbuf *out, time64_t sec)
480 void bch2_prt_date_seconds(struct printbuf *out, time64_t sec)
483 snprintf(buf, sizeof(buf), "%ptT", &sec);
488 #define TABSTOP_SIZE 12
490 static inline void pr_name_and_units(struct printbuf *out, const char *name, u64 ns)
494 bch2_pr_time_units_aligned(out, ns);
498 void bch2_time_stats_to_text(struct printbuf *out, struct bch2_time_stats *stats)
500 const struct time_unit *u;
501 s64 f_mean = 0, d_mean = 0;
502 u64 q, last_q = 0, f_stddev = 0, d_stddev = 0;
505 * avoid divide by zero
507 if (stats->freq_stats.n) {
508 f_mean = mean_and_variance_get_mean(stats->freq_stats);
509 f_stddev = mean_and_variance_get_stddev(stats->freq_stats);
510 d_mean = mean_and_variance_get_mean(stats->duration_stats);
511 d_stddev = mean_and_variance_get_stddev(stats->duration_stats);
514 printbuf_tabstop_push(out, out->indent + TABSTOP_SIZE);
515 prt_printf(out, "count:");
517 prt_printf(out, "%llu ",
518 stats->duration_stats.n);
519 printbuf_tabstop_pop(out);
522 printbuf_tabstops_reset(out);
524 printbuf_tabstop_push(out, out->indent + 20);
525 printbuf_tabstop_push(out, TABSTOP_SIZE + 2);
526 printbuf_tabstop_push(out, 0);
527 printbuf_tabstop_push(out, TABSTOP_SIZE + 2);
530 prt_printf(out, "since mount");
533 prt_printf(out, "recent");
537 printbuf_tabstops_reset(out);
538 printbuf_tabstop_push(out, out->indent + 20);
539 printbuf_tabstop_push(out, TABSTOP_SIZE);
540 printbuf_tabstop_push(out, 2);
541 printbuf_tabstop_push(out, TABSTOP_SIZE);
543 prt_printf(out, "duration of events");
545 printbuf_indent_add(out, 2);
547 pr_name_and_units(out, "min:", stats->min_duration);
548 pr_name_and_units(out, "max:", stats->max_duration);
550 prt_printf(out, "mean:");
552 bch2_pr_time_units_aligned(out, d_mean);
554 bch2_pr_time_units_aligned(out, mean_and_variance_weighted_get_mean(stats->duration_stats_weighted));
557 prt_printf(out, "stddev:");
559 bch2_pr_time_units_aligned(out, d_stddev);
561 bch2_pr_time_units_aligned(out, mean_and_variance_weighted_get_stddev(stats->duration_stats_weighted));
563 printbuf_indent_sub(out, 2);
566 prt_printf(out, "time between events");
568 printbuf_indent_add(out, 2);
570 pr_name_and_units(out, "min:", stats->min_freq);
571 pr_name_and_units(out, "max:", stats->max_freq);
573 prt_printf(out, "mean:");
575 bch2_pr_time_units_aligned(out, f_mean);
577 bch2_pr_time_units_aligned(out, mean_and_variance_weighted_get_mean(stats->freq_stats_weighted));
580 prt_printf(out, "stddev:");
582 bch2_pr_time_units_aligned(out, f_stddev);
584 bch2_pr_time_units_aligned(out, mean_and_variance_weighted_get_stddev(stats->freq_stats_weighted));
586 printbuf_indent_sub(out, 2);
589 printbuf_tabstops_reset(out);
591 i = eytzinger0_first(NR_QUANTILES);
592 u = pick_time_units(stats->quantiles.entries[i].m);
594 prt_printf(out, "quantiles (%s):\t", u->name);
595 eytzinger0_for_each(i, NR_QUANTILES) {
596 bool is_last = eytzinger0_next(i, NR_QUANTILES) == -1;
598 q = max(stats->quantiles.entries[i].m, last_q);
599 prt_printf(out, "%llu ",
600 div_u64(q, u->nsecs));
607 void bch2_time_stats_exit(struct bch2_time_stats *stats)
609 free_percpu(stats->buffer);
612 void bch2_time_stats_init(struct bch2_time_stats *stats)
614 memset(stats, 0, sizeof(*stats));
615 stats->duration_stats_weighted.weight = 8;
616 stats->freq_stats_weighted.weight = 8;
617 stats->min_duration = U64_MAX;
618 stats->min_freq = U64_MAX;
619 spin_lock_init(&stats->lock);
625 * bch2_ratelimit_delay() - return how long to delay until the next time to do
627 * @d: the struct bch_ratelimit to update
628 * Returns: the amount of time to delay by, in jiffies
630 u64 bch2_ratelimit_delay(struct bch_ratelimit *d)
632 u64 now = local_clock();
634 return time_after64(d->next, now)
635 ? nsecs_to_jiffies(d->next - now)
640 * bch2_ratelimit_increment() - increment @d by the amount of work done
641 * @d: the struct bch_ratelimit to update
642 * @done: the amount of work done, in arbitrary units
644 void bch2_ratelimit_increment(struct bch_ratelimit *d, u64 done)
646 u64 now = local_clock();
648 d->next += div_u64(done * NSEC_PER_SEC, d->rate);
650 if (time_before64(now + NSEC_PER_SEC, d->next))
651 d->next = now + NSEC_PER_SEC;
653 if (time_after64(now - NSEC_PER_SEC * 2, d->next))
654 d->next = now - NSEC_PER_SEC * 2;
660 * Updates pd_controller. Attempts to scale inputed values to units per second.
661 * @target: desired value
662 * @actual: current value
664 * @sign: 1 or -1; 1 if increasing the rate makes actual go up, -1 if increasing
665 * it makes actual go down.
667 void bch2_pd_controller_update(struct bch_pd_controller *pd,
668 s64 target, s64 actual, int sign)
670 s64 proportional, derivative, change;
672 unsigned long seconds_since_update = (jiffies - pd->last_update) / HZ;
674 if (seconds_since_update == 0)
677 pd->last_update = jiffies;
679 proportional = actual - target;
680 proportional *= seconds_since_update;
681 proportional = div_s64(proportional, pd->p_term_inverse);
683 derivative = actual - pd->last_actual;
684 derivative = div_s64(derivative, seconds_since_update);
685 derivative = ewma_add(pd->smoothed_derivative, derivative,
686 (pd->d_term / seconds_since_update) ?: 1);
687 derivative = derivative * pd->d_term;
688 derivative = div_s64(derivative, pd->p_term_inverse);
690 change = proportional + derivative;
692 /* Don't increase rate if not keeping up */
695 time_after64(local_clock(),
696 pd->rate.next + NSEC_PER_MSEC))
699 change *= (sign * -1);
701 pd->rate.rate = clamp_t(s64, (s64) pd->rate.rate + change,
704 pd->last_actual = actual;
705 pd->last_derivative = derivative;
706 pd->last_proportional = proportional;
707 pd->last_change = change;
708 pd->last_target = target;
711 void bch2_pd_controller_init(struct bch_pd_controller *pd)
713 pd->rate.rate = 1024;
714 pd->last_update = jiffies;
715 pd->p_term_inverse = 6000;
717 pd->d_smooth = pd->d_term;
718 pd->backpressure = 1;
721 void bch2_pd_controller_debug_to_text(struct printbuf *out, struct bch_pd_controller *pd)
723 if (!out->nr_tabstops)
724 printbuf_tabstop_push(out, 20);
726 prt_printf(out, "rate:");
728 prt_human_readable_s64(out, pd->rate.rate);
731 prt_printf(out, "target:");
733 prt_human_readable_u64(out, pd->last_target);
736 prt_printf(out, "actual:");
738 prt_human_readable_u64(out, pd->last_actual);
741 prt_printf(out, "proportional:");
743 prt_human_readable_s64(out, pd->last_proportional);
746 prt_printf(out, "derivative:");
748 prt_human_readable_s64(out, pd->last_derivative);
751 prt_printf(out, "change:");
753 prt_human_readable_s64(out, pd->last_change);
756 prt_printf(out, "next io:");
758 prt_printf(out, "%llims", div64_s64(pd->rate.next - local_clock(), NSEC_PER_MSEC));
764 void bch2_bio_map(struct bio *bio, void *base, size_t size)
767 struct page *page = is_vmalloc_addr(base)
768 ? vmalloc_to_page(base)
769 : virt_to_page(base);
770 unsigned offset = offset_in_page(base);
771 unsigned len = min_t(size_t, PAGE_SIZE - offset, size);
773 BUG_ON(!bio_add_page(bio, page, len, offset));
779 int bch2_bio_alloc_pages(struct bio *bio, size_t size, gfp_t gfp_mask)
782 struct page *page = alloc_pages(gfp_mask, 0);
783 unsigned len = min_t(size_t, PAGE_SIZE, size);
788 if (unlikely(!bio_add_page(bio, page, len, 0))) {
799 size_t bch2_rand_range(size_t max)
807 rand = get_random_long();
808 rand &= roundup_pow_of_two(max) - 1;
809 } while (rand >= max);
814 void memcpy_to_bio(struct bio *dst, struct bvec_iter dst_iter, const void *src)
817 struct bvec_iter iter;
819 __bio_for_each_segment(bv, dst, iter, dst_iter) {
820 void *dstp = kmap_local_page(bv.bv_page);
822 memcpy(dstp + bv.bv_offset, src, bv.bv_len);
829 void memcpy_from_bio(void *dst, struct bio *src, struct bvec_iter src_iter)
832 struct bvec_iter iter;
834 __bio_for_each_segment(bv, src, iter, src_iter) {
835 void *srcp = kmap_local_page(bv.bv_page);
837 memcpy(dst, srcp + bv.bv_offset, bv.bv_len);
844 static int alignment_ok(const void *base, size_t align)
846 return IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) ||
847 ((unsigned long)base & (align - 1)) == 0;
850 static void u32_swap(void *a, void *b, size_t size)
853 *(u32 *)a = *(u32 *)b;
857 static void u64_swap(void *a, void *b, size_t size)
860 *(u64 *)a = *(u64 *)b;
864 static void generic_swap(void *a, void *b, size_t size)
870 *(char *)a++ = *(char *)b;
872 } while (--size > 0);
875 static inline int do_cmp(void *base, size_t n, size_t size,
876 int (*cmp_func)(const void *, const void *, size_t),
879 return cmp_func(base + inorder_to_eytzinger0(l, n) * size,
880 base + inorder_to_eytzinger0(r, n) * size,
884 static inline void do_swap(void *base, size_t n, size_t size,
885 void (*swap_func)(void *, void *, size_t),
888 swap_func(base + inorder_to_eytzinger0(l, n) * size,
889 base + inorder_to_eytzinger0(r, n) * size,
893 void eytzinger0_sort(void *base, size_t n, size_t size,
894 int (*cmp_func)(const void *, const void *, size_t),
895 void (*swap_func)(void *, void *, size_t))
900 if (size == 4 && alignment_ok(base, 4))
901 swap_func = u32_swap;
902 else if (size == 8 && alignment_ok(base, 8))
903 swap_func = u64_swap;
905 swap_func = generic_swap;
909 for (i = n / 2 - 1; i >= 0; --i) {
910 for (r = i; r * 2 + 1 < n; r = c) {
914 do_cmp(base, n, size, cmp_func, c, c + 1) < 0)
917 if (do_cmp(base, n, size, cmp_func, r, c) >= 0)
920 do_swap(base, n, size, swap_func, r, c);
925 for (i = n - 1; i > 0; --i) {
926 do_swap(base, n, size, swap_func, 0, i);
928 for (r = 0; r * 2 + 1 < i; r = c) {
932 do_cmp(base, n, size, cmp_func, c, c + 1) < 0)
935 if (do_cmp(base, n, size, cmp_func, r, c) >= 0)
938 do_swap(base, n, size, swap_func, r, c);
943 void sort_cmp_size(void *base, size_t num, size_t size,
944 int (*cmp_func)(const void *, const void *, size_t),
945 void (*swap_func)(void *, void *, size_t size))
947 /* pre-scale counters for performance */
948 int i = (num/2 - 1) * size, n = num * size, c, r;
951 if (size == 4 && alignment_ok(base, 4))
952 swap_func = u32_swap;
953 else if (size == 8 && alignment_ok(base, 8))
954 swap_func = u64_swap;
956 swap_func = generic_swap;
960 for ( ; i >= 0; i -= size) {
961 for (r = i; r * 2 + size < n; r = c) {
964 cmp_func(base + c, base + c + size, size) < 0)
966 if (cmp_func(base + r, base + c, size) >= 0)
968 swap_func(base + r, base + c, size);
973 for (i = n - size; i > 0; i -= size) {
974 swap_func(base, base + i, size);
975 for (r = 0; r * 2 + size < i; r = c) {
978 cmp_func(base + c, base + c + size, size) < 0)
980 if (cmp_func(base + r, base + c, size) >= 0)
982 swap_func(base + r, base + c, size);
987 static void mempool_free_vp(void *element, void *pool_data)
989 size_t size = (size_t) pool_data;
991 vpfree(element, size);
994 static void *mempool_alloc_vp(gfp_t gfp_mask, void *pool_data)
996 size_t size = (size_t) pool_data;
998 return vpmalloc(size, gfp_mask);
1001 int mempool_init_kvpmalloc_pool(mempool_t *pool, int min_nr, size_t size)
1003 return size < PAGE_SIZE
1004 ? mempool_init_kmalloc_pool(pool, min_nr, size)
1005 : mempool_init(pool, min_nr, mempool_alloc_vp,
1006 mempool_free_vp, (void *) size);
1010 void eytzinger1_test(void)
1012 unsigned inorder, eytz, size;
1014 pr_info("1 based eytzinger test:");
1019 unsigned extra = eytzinger1_extra(size);
1022 pr_info("tree size %u", size);
1024 BUG_ON(eytzinger1_prev(0, size) != eytzinger1_last(size));
1025 BUG_ON(eytzinger1_next(0, size) != eytzinger1_first(size));
1027 BUG_ON(eytzinger1_prev(eytzinger1_first(size), size) != 0);
1028 BUG_ON(eytzinger1_next(eytzinger1_last(size), size) != 0);
1031 eytzinger1_for_each(eytz, size) {
1032 BUG_ON(__inorder_to_eytzinger1(inorder, size, extra) != eytz);
1033 BUG_ON(__eytzinger1_to_inorder(eytz, size, extra) != inorder);
1034 BUG_ON(eytz != eytzinger1_last(size) &&
1035 eytzinger1_prev(eytzinger1_next(eytz, size), size) != eytz);
1042 void eytzinger0_test(void)
1045 unsigned inorder, eytz, size;
1047 pr_info("0 based eytzinger test:");
1052 unsigned extra = eytzinger0_extra(size);
1055 pr_info("tree size %u", size);
1057 BUG_ON(eytzinger0_prev(-1, size) != eytzinger0_last(size));
1058 BUG_ON(eytzinger0_next(-1, size) != eytzinger0_first(size));
1060 BUG_ON(eytzinger0_prev(eytzinger0_first(size), size) != -1);
1061 BUG_ON(eytzinger0_next(eytzinger0_last(size), size) != -1);
1064 eytzinger0_for_each(eytz, size) {
1065 BUG_ON(__inorder_to_eytzinger0(inorder, size, extra) != eytz);
1066 BUG_ON(__eytzinger0_to_inorder(eytz, size, extra) != inorder);
1067 BUG_ON(eytz != eytzinger0_last(size) &&
1068 eytzinger0_prev(eytzinger0_next(eytz, size), size) != eytz);
1075 static inline int cmp_u16(const void *_l, const void *_r, size_t size)
1077 const u16 *l = _l, *r = _r;
1079 return (*l > *r) - (*r - *l);
1082 static void eytzinger0_find_test_val(u16 *test_array, unsigned nr, u16 search)
1084 int i, c1 = -1, c2 = -1;
1087 r = eytzinger0_find_le(test_array, nr,
1088 sizeof(test_array[0]),
1093 for (i = 0; i < nr; i++)
1094 if (test_array[i] <= search && test_array[i] > c2)
1098 eytzinger0_for_each(i, nr)
1099 pr_info("[%3u] = %12u", i, test_array[i]);
1100 pr_info("find_le(%2u) -> [%2zi] = %2i should be %2i",
1105 void eytzinger0_find_test(void)
1107 unsigned i, nr, allocated = 1 << 12;
1108 u16 *test_array = kmalloc_array(allocated, sizeof(test_array[0]), GFP_KERNEL);
1110 for (nr = 1; nr < allocated; nr++) {
1111 pr_info("testing %u elems", nr);
1113 get_random_bytes(test_array, nr * sizeof(test_array[0]));
1114 eytzinger0_sort(test_array, nr, sizeof(test_array[0]), cmp_u16, NULL);
1116 /* verify array is sorted correctly: */
1117 eytzinger0_for_each(i, nr)
1118 BUG_ON(i != eytzinger0_last(nr) &&
1119 test_array[i] > test_array[eytzinger0_next(i, nr)]);
1121 for (i = 0; i < U16_MAX; i += 1 << 12)
1122 eytzinger0_find_test_val(test_array, nr, i);
1124 for (i = 0; i < nr; i++) {
1125 eytzinger0_find_test_val(test_array, nr, test_array[i] - 1);
1126 eytzinger0_find_test_val(test_array, nr, test_array[i]);
1127 eytzinger0_find_test_val(test_array, nr, test_array[i] + 1);
1136 * Accumulate percpu counters onto one cpu's copy - only valid when access
1137 * against any percpu counter is guarded against
1139 u64 *bch2_acc_percpu_u64s(u64 __percpu *p, unsigned nr)
1144 /* access to pcpu vars has to be blocked by other locking */
1146 ret = this_cpu_ptr(p);
1149 for_each_possible_cpu(cpu) {
1150 u64 *i = per_cpu_ptr(p, cpu);
1153 acc_u64s(ret, i, nr);
1154 memset(i, 0, nr * sizeof(u64));