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-rw-r--r--fs/bcachefs/util.c1160
1 files changed, 1160 insertions, 0 deletions
diff --git a/fs/bcachefs/util.c b/fs/bcachefs/util.c
new file mode 100644
index 0000000000..3b7c349f26
--- /dev/null
+++ b/fs/bcachefs/util.c
@@ -0,0 +1,1160 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * random utiility code, for bcache but in theory not specific to bcache
+ *
+ * Copyright 2010, 2011 Kent Overstreet <kent.overstreet@gmail.com>
+ * Copyright 2012 Google, Inc.
+ */
+
+#include <linux/bio.h>
+#include <linux/blkdev.h>
+#include <linux/console.h>
+#include <linux/ctype.h>
+#include <linux/debugfs.h>
+#include <linux/freezer.h>
+#include <linux/kthread.h>
+#include <linux/log2.h>
+#include <linux/math64.h>
+#include <linux/percpu.h>
+#include <linux/preempt.h>
+#include <linux/random.h>
+#include <linux/seq_file.h>
+#include <linux/string.h>
+#include <linux/types.h>
+#include <linux/sched/clock.h>
+
+#include "eytzinger.h"
+#include "mean_and_variance.h"
+#include "util.h"
+
+static const char si_units[] = "?kMGTPEZY";
+
+/* string_get_size units: */
+static const char *const units_2[] = {
+ "B", "KiB", "MiB", "GiB", "TiB", "PiB", "EiB", "ZiB", "YiB"
+};
+static const char *const units_10[] = {
+ "B", "kB", "MB", "GB", "TB", "PB", "EB", "ZB", "YB"
+};
+
+static int parse_u64(const char *cp, u64 *res)
+{
+ const char *start = cp;
+ u64 v = 0;
+
+ if (!isdigit(*cp))
+ return -EINVAL;
+
+ do {
+ if (v > U64_MAX / 10)
+ return -ERANGE;
+ v *= 10;
+ if (v > U64_MAX - (*cp - '0'))
+ return -ERANGE;
+ v += *cp - '0';
+ cp++;
+ } while (isdigit(*cp));
+
+ *res = v;
+ return cp - start;
+}
+
+static int bch2_pow(u64 n, u64 p, u64 *res)
+{
+ *res = 1;
+
+ while (p--) {
+ if (*res > div_u64(U64_MAX, n))
+ return -ERANGE;
+ *res *= n;
+ }
+ return 0;
+}
+
+static int parse_unit_suffix(const char *cp, u64 *res)
+{
+ const char *start = cp;
+ u64 base = 1024;
+ unsigned u;
+ int ret;
+
+ if (*cp == ' ')
+ cp++;
+
+ for (u = 1; u < strlen(si_units); u++)
+ if (*cp == si_units[u]) {
+ cp++;
+ goto got_unit;
+ }
+
+ for (u = 0; u < ARRAY_SIZE(units_2); u++)
+ if (!strncmp(cp, units_2[u], strlen(units_2[u]))) {
+ cp += strlen(units_2[u]);
+ goto got_unit;
+ }
+
+ for (u = 0; u < ARRAY_SIZE(units_10); u++)
+ if (!strncmp(cp, units_10[u], strlen(units_10[u]))) {
+ cp += strlen(units_10[u]);
+ base = 1000;
+ goto got_unit;
+ }
+
+ *res = 1;
+ return 0;
+got_unit:
+ ret = bch2_pow(base, u, res);
+ if (ret)
+ return ret;
+
+ return cp - start;
+}
+
+#define parse_or_ret(cp, _f) \
+do { \
+ int _ret = _f; \
+ if (_ret < 0) \
+ return _ret; \
+ cp += _ret; \
+} while (0)
+
+static int __bch2_strtou64_h(const char *cp, u64 *res)
+{
+ const char *start = cp;
+ u64 v = 0, b, f_n = 0, f_d = 1;
+ int ret;
+
+ parse_or_ret(cp, parse_u64(cp, &v));
+
+ if (*cp == '.') {
+ cp++;
+ ret = parse_u64(cp, &f_n);
+ if (ret < 0)
+ return ret;
+ cp += ret;
+
+ ret = bch2_pow(10, ret, &f_d);
+ if (ret)
+ return ret;
+ }
+
+ parse_or_ret(cp, parse_unit_suffix(cp, &b));
+
+ if (v > div_u64(U64_MAX, b))
+ return -ERANGE;
+ v *= b;
+
+ if (f_n > div_u64(U64_MAX, b))
+ return -ERANGE;
+
+ f_n = div_u64(f_n * b, f_d);
+ if (v + f_n < v)
+ return -ERANGE;
+ v += f_n;
+
+ *res = v;
+ return cp - start;
+}
+
+static int __bch2_strtoh(const char *cp, u64 *res,
+ u64 t_max, bool t_signed)
+{
+ bool positive = *cp != '-';
+ u64 v = 0;
+
+ if (*cp == '+' || *cp == '-')
+ cp++;
+
+ parse_or_ret(cp, __bch2_strtou64_h(cp, &v));
+
+ if (*cp == '\n')
+ cp++;
+ if (*cp)
+ return -EINVAL;
+
+ if (positive) {
+ if (v > t_max)
+ return -ERANGE;
+ } else {
+ if (v && !t_signed)
+ return -ERANGE;
+
+ if (v > t_max + 1)
+ return -ERANGE;
+ v = -v;
+ }
+
+ *res = v;
+ return 0;
+}
+
+#define STRTO_H(name, type) \
+int bch2_ ## name ## _h(const char *cp, type *res) \
+{ \
+ u64 v = 0; \
+ int ret = __bch2_strtoh(cp, &v, ANYSINT_MAX(type), \
+ ANYSINT_MAX(type) != ((type) ~0ULL)); \
+ *res = v; \
+ return ret; \
+}
+
+STRTO_H(strtoint, int)
+STRTO_H(strtouint, unsigned int)
+STRTO_H(strtoll, long long)
+STRTO_H(strtoull, unsigned long long)
+STRTO_H(strtou64, u64)
+
+u64 bch2_read_flag_list(char *opt, const char * const list[])
+{
+ u64 ret = 0;
+ char *p, *s, *d = kstrdup(opt, GFP_KERNEL);
+
+ if (!d)
+ return -ENOMEM;
+
+ s = strim(d);
+
+ while ((p = strsep(&s, ","))) {
+ int flag = match_string(list, -1, p);
+
+ if (flag < 0) {
+ ret = -1;
+ break;
+ }
+
+ ret |= 1 << flag;
+ }
+
+ kfree(d);
+
+ return ret;
+}
+
+bool bch2_is_zero(const void *_p, size_t n)
+{
+ const char *p = _p;
+ size_t i;
+
+ for (i = 0; i < n; i++)
+ if (p[i])
+ return false;
+ return true;
+}
+
+void bch2_prt_u64_binary(struct printbuf *out, u64 v, unsigned nr_bits)
+{
+ while (nr_bits)
+ prt_char(out, '0' + ((v >> --nr_bits) & 1));
+}
+
+void bch2_print_string_as_lines(const char *prefix, const char *lines)
+{
+ const char *p;
+
+ if (!lines) {
+ printk("%s (null)\n", prefix);
+ return;
+ }
+
+ console_lock();
+ while (1) {
+ p = strchrnul(lines, '\n');
+ printk("%s%.*s\n", prefix, (int) (p - lines), lines);
+ if (!*p)
+ break;
+ lines = p + 1;
+ }
+ console_unlock();
+}
+
+int bch2_save_backtrace(bch_stacktrace *stack, struct task_struct *task)
+{
+#ifdef CONFIG_STACKTRACE
+ unsigned nr_entries = 0;
+ int ret = 0;
+
+ stack->nr = 0;
+ ret = darray_make_room(stack, 32);
+ if (ret)
+ return ret;
+
+ if (!down_read_trylock(&task->signal->exec_update_lock))
+ return -1;
+
+ do {
+ nr_entries = stack_trace_save_tsk(task, stack->data, stack->size, 0);
+ } while (nr_entries == stack->size &&
+ !(ret = darray_make_room(stack, stack->size * 2)));
+
+ stack->nr = nr_entries;
+ up_read(&task->signal->exec_update_lock);
+
+ return ret;
+#else
+ return 0;
+#endif
+}
+
+void bch2_prt_backtrace(struct printbuf *out, bch_stacktrace *stack)
+{
+ unsigned long *i;
+
+ darray_for_each(*stack, i) {
+ prt_printf(out, "[<0>] %pB", (void *) *i);
+ prt_newline(out);
+ }
+}
+
+int bch2_prt_task_backtrace(struct printbuf *out, struct task_struct *task)
+{
+ bch_stacktrace stack = { 0 };
+ int ret = bch2_save_backtrace(&stack, task);
+
+ bch2_prt_backtrace(out, &stack);
+ darray_exit(&stack);
+ return ret;
+}
+
+/* time stats: */
+
+#ifndef CONFIG_BCACHEFS_NO_LATENCY_ACCT
+static void bch2_quantiles_update(struct bch2_quantiles *q, u64 v)
+{
+ unsigned i = 0;
+
+ while (i < ARRAY_SIZE(q->entries)) {
+ struct bch2_quantile_entry *e = q->entries + i;
+
+ if (unlikely(!e->step)) {
+ e->m = v;
+ e->step = max_t(unsigned, v / 2, 1024);
+ } else if (e->m > v) {
+ e->m = e->m >= e->step
+ ? e->m - e->step
+ : 0;
+ } else if (e->m < v) {
+ e->m = e->m + e->step > e->m
+ ? e->m + e->step
+ : U32_MAX;
+ }
+
+ if ((e->m > v ? e->m - v : v - e->m) < e->step)
+ e->step = max_t(unsigned, e->step / 2, 1);
+
+ if (v >= e->m)
+ break;
+
+ i = eytzinger0_child(i, v > e->m);
+ }
+}
+
+static inline void bch2_time_stats_update_one(struct bch2_time_stats *stats,
+ u64 start, u64 end)
+{
+ u64 duration, freq;
+
+ if (time_after64(end, start)) {
+ duration = end - start;
+ mean_and_variance_update(&stats->duration_stats, duration);
+ mean_and_variance_weighted_update(&stats->duration_stats_weighted, duration);
+ stats->max_duration = max(stats->max_duration, duration);
+ stats->min_duration = min(stats->min_duration, duration);
+ bch2_quantiles_update(&stats->quantiles, duration);
+ }
+
+ if (stats->last_event && time_after64(end, stats->last_event)) {
+ freq = end - stats->last_event;
+ mean_and_variance_update(&stats->freq_stats, freq);
+ mean_and_variance_weighted_update(&stats->freq_stats_weighted, freq);
+ stats->max_freq = max(stats->max_freq, freq);
+ stats->min_freq = min(stats->min_freq, freq);
+ }
+
+ stats->last_event = end;
+}
+
+static noinline void bch2_time_stats_clear_buffer(struct bch2_time_stats *stats,
+ struct bch2_time_stat_buffer *b)
+{
+ struct bch2_time_stat_buffer_entry *i;
+ unsigned long flags;
+
+ spin_lock_irqsave(&stats->lock, flags);
+ for (i = b->entries;
+ i < b->entries + ARRAY_SIZE(b->entries);
+ i++)
+ bch2_time_stats_update_one(stats, i->start, i->end);
+ spin_unlock_irqrestore(&stats->lock, flags);
+
+ b->nr = 0;
+}
+
+void __bch2_time_stats_update(struct bch2_time_stats *stats, u64 start, u64 end)
+{
+ unsigned long flags;
+
+ WARN_RATELIMIT(!stats->min_duration || !stats->min_freq,
+ "time_stats: min_duration = %llu, min_freq = %llu",
+ stats->min_duration, stats->min_freq);
+
+ if (!stats->buffer) {
+ spin_lock_irqsave(&stats->lock, flags);
+ bch2_time_stats_update_one(stats, start, end);
+
+ if (mean_and_variance_weighted_get_mean(stats->freq_stats_weighted) < 32 &&
+ stats->duration_stats.n > 1024)
+ stats->buffer =
+ alloc_percpu_gfp(struct bch2_time_stat_buffer,
+ GFP_ATOMIC);
+ spin_unlock_irqrestore(&stats->lock, flags);
+ } else {
+ struct bch2_time_stat_buffer *b;
+
+ preempt_disable();
+ b = this_cpu_ptr(stats->buffer);
+
+ BUG_ON(b->nr >= ARRAY_SIZE(b->entries));
+ b->entries[b->nr++] = (struct bch2_time_stat_buffer_entry) {
+ .start = start,
+ .end = end
+ };
+
+ if (unlikely(b->nr == ARRAY_SIZE(b->entries)))
+ bch2_time_stats_clear_buffer(stats, b);
+ preempt_enable();
+ }
+}
+#endif
+
+static const struct time_unit {
+ const char *name;
+ u64 nsecs;
+} time_units[] = {
+ { "ns", 1 },
+ { "us", NSEC_PER_USEC },
+ { "ms", NSEC_PER_MSEC },
+ { "s", NSEC_PER_SEC },
+ { "m", (u64) NSEC_PER_SEC * 60},
+ { "h", (u64) NSEC_PER_SEC * 3600},
+ { "eon", U64_MAX },
+};
+
+static const struct time_unit *pick_time_units(u64 ns)
+{
+ const struct time_unit *u;
+
+ for (u = time_units;
+ u + 1 < time_units + ARRAY_SIZE(time_units) &&
+ ns >= u[1].nsecs << 1;
+ u++)
+ ;
+
+ return u;
+}
+
+void bch2_pr_time_units(struct printbuf *out, u64 ns)
+{
+ const struct time_unit *u = pick_time_units(ns);
+
+ prt_printf(out, "%llu %s", div_u64(ns, u->nsecs), u->name);
+}
+
+static void bch2_pr_time_units_aligned(struct printbuf *out, u64 ns)
+{
+ const struct time_unit *u = pick_time_units(ns);
+
+ prt_printf(out, "%llu ", div64_u64(ns, u->nsecs));
+ prt_tab_rjust(out);
+ prt_printf(out, "%s", u->name);
+}
+
+#ifndef __KERNEL__
+#include <time.h>
+void bch2_prt_datetime(struct printbuf *out, time64_t sec)
+{
+ time_t t = sec;
+ char buf[64];
+ ctime_r(&t, buf);
+ prt_str(out, buf);
+}
+#else
+void bch2_prt_datetime(struct printbuf *out, time64_t sec)
+{
+ char buf[64];
+ snprintf(buf, sizeof(buf), "%ptT", &sec);
+ prt_u64(out, sec);
+}
+#endif
+
+#define TABSTOP_SIZE 12
+
+static inline void pr_name_and_units(struct printbuf *out, const char *name, u64 ns)
+{
+ prt_str(out, name);
+ prt_tab(out);
+ bch2_pr_time_units_aligned(out, ns);
+ prt_newline(out);
+}
+
+void bch2_time_stats_to_text(struct printbuf *out, struct bch2_time_stats *stats)
+{
+ const struct time_unit *u;
+ s64 f_mean = 0, d_mean = 0;
+ u64 q, last_q = 0, f_stddev = 0, d_stddev = 0;
+ int i;
+ /*
+ * avoid divide by zero
+ */
+ if (stats->freq_stats.n) {
+ f_mean = mean_and_variance_get_mean(stats->freq_stats);
+ f_stddev = mean_and_variance_get_stddev(stats->freq_stats);
+ d_mean = mean_and_variance_get_mean(stats->duration_stats);
+ d_stddev = mean_and_variance_get_stddev(stats->duration_stats);
+ }
+
+ printbuf_tabstop_push(out, out->indent + TABSTOP_SIZE);
+ prt_printf(out, "count:");
+ prt_tab(out);
+ prt_printf(out, "%llu ",
+ stats->duration_stats.n);
+ printbuf_tabstop_pop(out);
+ prt_newline(out);
+
+ printbuf_tabstops_reset(out);
+
+ printbuf_tabstop_push(out, out->indent + 20);
+ printbuf_tabstop_push(out, TABSTOP_SIZE + 2);
+ printbuf_tabstop_push(out, 0);
+ printbuf_tabstop_push(out, TABSTOP_SIZE + 2);
+
+ prt_tab(out);
+ prt_printf(out, "since mount");
+ prt_tab_rjust(out);
+ prt_tab(out);
+ prt_printf(out, "recent");
+ prt_tab_rjust(out);
+ prt_newline(out);
+
+ printbuf_tabstops_reset(out);
+ printbuf_tabstop_push(out, out->indent + 20);
+ printbuf_tabstop_push(out, TABSTOP_SIZE);
+ printbuf_tabstop_push(out, 2);
+ printbuf_tabstop_push(out, TABSTOP_SIZE);
+
+ prt_printf(out, "duration of events");
+ prt_newline(out);
+ printbuf_indent_add(out, 2);
+
+ pr_name_and_units(out, "min:", stats->min_duration);
+ pr_name_and_units(out, "max:", stats->max_duration);
+
+ prt_printf(out, "mean:");
+ prt_tab(out);
+ bch2_pr_time_units_aligned(out, d_mean);
+ prt_tab(out);
+ bch2_pr_time_units_aligned(out, mean_and_variance_weighted_get_mean(stats->duration_stats_weighted));
+ prt_newline(out);
+
+ prt_printf(out, "stddev:");
+ prt_tab(out);
+ bch2_pr_time_units_aligned(out, d_stddev);
+ prt_tab(out);
+ bch2_pr_time_units_aligned(out, mean_and_variance_weighted_get_stddev(stats->duration_stats_weighted));
+
+ printbuf_indent_sub(out, 2);
+ prt_newline(out);
+
+ prt_printf(out, "time between events");
+ prt_newline(out);
+ printbuf_indent_add(out, 2);
+
+ pr_name_and_units(out, "min:", stats->min_freq);
+ pr_name_and_units(out, "max:", stats->max_freq);
+
+ prt_printf(out, "mean:");
+ prt_tab(out);
+ bch2_pr_time_units_aligned(out, f_mean);
+ prt_tab(out);
+ bch2_pr_time_units_aligned(out, mean_and_variance_weighted_get_mean(stats->freq_stats_weighted));
+ prt_newline(out);
+
+ prt_printf(out, "stddev:");
+ prt_tab(out);
+ bch2_pr_time_units_aligned(out, f_stddev);
+ prt_tab(out);
+ bch2_pr_time_units_aligned(out, mean_and_variance_weighted_get_stddev(stats->freq_stats_weighted));
+
+ printbuf_indent_sub(out, 2);
+ prt_newline(out);
+
+ printbuf_tabstops_reset(out);
+
+ i = eytzinger0_first(NR_QUANTILES);
+ u = pick_time_units(stats->quantiles.entries[i].m);
+
+ prt_printf(out, "quantiles (%s):\t", u->name);
+ eytzinger0_for_each(i, NR_QUANTILES) {
+ bool is_last = eytzinger0_next(i, NR_QUANTILES) == -1;
+
+ q = max(stats->quantiles.entries[i].m, last_q);
+ prt_printf(out, "%llu ",
+ div_u64(q, u->nsecs));
+ if (is_last)
+ prt_newline(out);
+ last_q = q;
+ }
+}
+
+void bch2_time_stats_exit(struct bch2_time_stats *stats)
+{
+ free_percpu(stats->buffer);
+}
+
+void bch2_time_stats_init(struct bch2_time_stats *stats)
+{
+ memset(stats, 0, sizeof(*stats));
+ stats->duration_stats_weighted.weight = 8;
+ stats->freq_stats_weighted.weight = 8;
+ stats->min_duration = U64_MAX;
+ stats->min_freq = U64_MAX;
+ spin_lock_init(&stats->lock);
+}
+
+/* ratelimit: */
+
+/**
+ * bch2_ratelimit_delay() - return how long to delay until the next time to do
+ * some work
+ * @d: the struct bch_ratelimit to update
+ * Returns: the amount of time to delay by, in jiffies
+ */
+u64 bch2_ratelimit_delay(struct bch_ratelimit *d)
+{
+ u64 now = local_clock();
+
+ return time_after64(d->next, now)
+ ? nsecs_to_jiffies(d->next - now)
+ : 0;
+}
+
+/**
+ * bch2_ratelimit_increment() - increment @d by the amount of work done
+ * @d: the struct bch_ratelimit to update
+ * @done: the amount of work done, in arbitrary units
+ */
+void bch2_ratelimit_increment(struct bch_ratelimit *d, u64 done)
+{
+ u64 now = local_clock();
+
+ d->next += div_u64(done * NSEC_PER_SEC, d->rate);
+
+ if (time_before64(now + NSEC_PER_SEC, d->next))
+ d->next = now + NSEC_PER_SEC;
+
+ if (time_after64(now - NSEC_PER_SEC * 2, d->next))
+ d->next = now - NSEC_PER_SEC * 2;
+}
+
+/* pd controller: */
+
+/*
+ * Updates pd_controller. Attempts to scale inputed values to units per second.
+ * @target: desired value
+ * @actual: current value
+ *
+ * @sign: 1 or -1; 1 if increasing the rate makes actual go up, -1 if increasing
+ * it makes actual go down.
+ */
+void bch2_pd_controller_update(struct bch_pd_controller *pd,
+ s64 target, s64 actual, int sign)
+{
+ s64 proportional, derivative, change;
+
+ unsigned long seconds_since_update = (jiffies - pd->last_update) / HZ;
+
+ if (seconds_since_update == 0)
+ return;
+
+ pd->last_update = jiffies;
+
+ proportional = actual - target;
+ proportional *= seconds_since_update;
+ proportional = div_s64(proportional, pd->p_term_inverse);
+
+ derivative = actual - pd->last_actual;
+ derivative = div_s64(derivative, seconds_since_update);
+ derivative = ewma_add(pd->smoothed_derivative, derivative,
+ (pd->d_term / seconds_since_update) ?: 1);
+ derivative = derivative * pd->d_term;
+ derivative = div_s64(derivative, pd->p_term_inverse);
+
+ change = proportional + derivative;
+
+ /* Don't increase rate if not keeping up */
+ if (change > 0 &&
+ pd->backpressure &&
+ time_after64(local_clock(),
+ pd->rate.next + NSEC_PER_MSEC))
+ change = 0;
+
+ change *= (sign * -1);
+
+ pd->rate.rate = clamp_t(s64, (s64) pd->rate.rate + change,
+ 1, UINT_MAX);
+
+ pd->last_actual = actual;
+ pd->last_derivative = derivative;
+ pd->last_proportional = proportional;
+ pd->last_change = change;
+ pd->last_target = target;
+}
+
+void bch2_pd_controller_init(struct bch_pd_controller *pd)
+{
+ pd->rate.rate = 1024;
+ pd->last_update = jiffies;
+ pd->p_term_inverse = 6000;
+ pd->d_term = 30;
+ pd->d_smooth = pd->d_term;
+ pd->backpressure = 1;
+}
+
+void bch2_pd_controller_debug_to_text(struct printbuf *out, struct bch_pd_controller *pd)
+{
+ if (!out->nr_tabstops)
+ printbuf_tabstop_push(out, 20);
+
+ prt_printf(out, "rate:");
+ prt_tab(out);
+ prt_human_readable_s64(out, pd->rate.rate);
+ prt_newline(out);
+
+ prt_printf(out, "target:");
+ prt_tab(out);
+ prt_human_readable_u64(out, pd->last_target);
+ prt_newline(out);
+
+ prt_printf(out, "actual:");
+ prt_tab(out);
+ prt_human_readable_u64(out, pd->last_actual);
+ prt_newline(out);
+
+ prt_printf(out, "proportional:");
+ prt_tab(out);
+ prt_human_readable_s64(out, pd->last_proportional);
+ prt_newline(out);
+
+ prt_printf(out, "derivative:");
+ prt_tab(out);
+ prt_human_readable_s64(out, pd->last_derivative);
+ prt_newline(out);
+
+ prt_printf(out, "change:");
+ prt_tab(out);
+ prt_human_readable_s64(out, pd->last_change);
+ prt_newline(out);
+
+ prt_printf(out, "next io:");
+ prt_tab(out);
+ prt_printf(out, "%llims", div64_s64(pd->rate.next - local_clock(), NSEC_PER_MSEC));
+ prt_newline(out);
+}
+
+/* misc: */
+
+void bch2_bio_map(struct bio *bio, void *base, size_t size)
+{
+ while (size) {
+ struct page *page = is_vmalloc_addr(base)
+ ? vmalloc_to_page(base)
+ : virt_to_page(base);
+ unsigned offset = offset_in_page(base);
+ unsigned len = min_t(size_t, PAGE_SIZE - offset, size);
+
+ BUG_ON(!bio_add_page(bio, page, len, offset));
+ size -= len;
+ base += len;
+ }
+}
+
+int bch2_bio_alloc_pages(struct bio *bio, size_t size, gfp_t gfp_mask)
+{
+ while (size) {
+ struct page *page = alloc_pages(gfp_mask, 0);
+ unsigned len = min_t(size_t, PAGE_SIZE, size);
+
+ if (!page)
+ return -ENOMEM;
+
+ if (unlikely(!bio_add_page(bio, page, len, 0))) {
+ __free_page(page);
+ break;
+ }
+
+ size -= len;
+ }
+
+ return 0;
+}
+
+size_t bch2_rand_range(size_t max)
+{
+ size_t rand;
+
+ if (!max)
+ return 0;
+
+ do {
+ rand = get_random_long();
+ rand &= roundup_pow_of_two(max) - 1;
+ } while (rand >= max);
+
+ return rand;
+}
+
+void memcpy_to_bio(struct bio *dst, struct bvec_iter dst_iter, const void *src)
+{
+ struct bio_vec bv;
+ struct bvec_iter iter;
+
+ __bio_for_each_segment(bv, dst, iter, dst_iter) {
+ void *dstp = kmap_local_page(bv.bv_page);
+
+ memcpy(dstp + bv.bv_offset, src, bv.bv_len);
+ kunmap_local(dstp);
+
+ src += bv.bv_len;
+ }
+}
+
+void memcpy_from_bio(void *dst, struct bio *src, struct bvec_iter src_iter)
+{
+ struct bio_vec bv;
+ struct bvec_iter iter;
+
+ __bio_for_each_segment(bv, src, iter, src_iter) {
+ void *srcp = kmap_local_page(bv.bv_page);
+
+ memcpy(dst, srcp + bv.bv_offset, bv.bv_len);
+ kunmap_local(srcp);
+
+ dst += bv.bv_len;
+ }
+}
+
+static int alignment_ok(const void *base, size_t align)
+{
+ return IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) ||
+ ((unsigned long)base & (align - 1)) == 0;
+}
+
+static void u32_swap(void *a, void *b, size_t size)
+{
+ u32 t = *(u32 *)a;
+ *(u32 *)a = *(u32 *)b;
+ *(u32 *)b = t;
+}
+
+static void u64_swap(void *a, void *b, size_t size)
+{
+ u64 t = *(u64 *)a;
+ *(u64 *)a = *(u64 *)b;
+ *(u64 *)b = t;
+}
+
+static void generic_swap(void *a, void *b, size_t size)
+{
+ char t;
+
+ do {
+ t = *(char *)a;
+ *(char *)a++ = *(char *)b;
+ *(char *)b++ = t;
+ } while (--size > 0);
+}
+
+static inline int do_cmp(void *base, size_t n, size_t size,
+ int (*cmp_func)(const void *, const void *, size_t),
+ size_t l, size_t r)
+{
+ return cmp_func(base + inorder_to_eytzinger0(l, n) * size,
+ base + inorder_to_eytzinger0(r, n) * size,
+ size);
+}
+
+static inline void do_swap(void *base, size_t n, size_t size,
+ void (*swap_func)(void *, void *, size_t),
+ size_t l, size_t r)
+{
+ swap_func(base + inorder_to_eytzinger0(l, n) * size,
+ base + inorder_to_eytzinger0(r, n) * size,
+ size);
+}
+
+void eytzinger0_sort(void *base, size_t n, size_t size,
+ int (*cmp_func)(const void *, const void *, size_t),
+ void (*swap_func)(void *, void *, size_t))
+{
+ int i, c, r;
+
+ if (!swap_func) {
+ if (size == 4 && alignment_ok(base, 4))
+ swap_func = u32_swap;
+ else if (size == 8 && alignment_ok(base, 8))
+ swap_func = u64_swap;
+ else
+ swap_func = generic_swap;
+ }
+
+ /* heapify */
+ for (i = n / 2 - 1; i >= 0; --i) {
+ for (r = i; r * 2 + 1 < n; r = c) {
+ c = r * 2 + 1;
+
+ if (c + 1 < n &&
+ do_cmp(base, n, size, cmp_func, c, c + 1) < 0)
+ c++;
+
+ if (do_cmp(base, n, size, cmp_func, r, c) >= 0)
+ break;
+
+ do_swap(base, n, size, swap_func, r, c);
+ }
+ }
+
+ /* sort */
+ for (i = n - 1; i > 0; --i) {
+ do_swap(base, n, size, swap_func, 0, i);
+
+ for (r = 0; r * 2 + 1 < i; r = c) {
+ c = r * 2 + 1;
+
+ if (c + 1 < i &&
+ do_cmp(base, n, size, cmp_func, c, c + 1) < 0)
+ c++;
+
+ if (do_cmp(base, n, size, cmp_func, r, c) >= 0)
+ break;
+
+ do_swap(base, n, size, swap_func, r, c);
+ }
+ }
+}
+
+void sort_cmp_size(void *base, size_t num, size_t size,
+ int (*cmp_func)(const void *, const void *, size_t),
+ void (*swap_func)(void *, void *, size_t size))
+{
+ /* pre-scale counters for performance */
+ int i = (num/2 - 1) * size, n = num * size, c, r;
+
+ if (!swap_func) {
+ if (size == 4 && alignment_ok(base, 4))
+ swap_func = u32_swap;
+ else if (size == 8 && alignment_ok(base, 8))
+ swap_func = u64_swap;
+ else
+ swap_func = generic_swap;
+ }
+
+ /* heapify */
+ for ( ; i >= 0; i -= size) {
+ for (r = i; r * 2 + size < n; r = c) {
+ c = r * 2 + size;
+ if (c < n - size &&
+ cmp_func(base + c, base + c + size, size) < 0)
+ c += size;
+ if (cmp_func(base + r, base + c, size) >= 0)
+ break;
+ swap_func(base + r, base + c, size);
+ }
+ }
+
+ /* sort */
+ for (i = n - size; i > 0; i -= size) {
+ swap_func(base, base + i, size);
+ for (r = 0; r * 2 + size < i; r = c) {
+ c = r * 2 + size;
+ if (c < i - size &&
+ cmp_func(base + c, base + c + size, size) < 0)
+ c += size;
+ if (cmp_func(base + r, base + c, size) >= 0)
+ break;
+ swap_func(base + r, base + c, size);
+ }
+ }
+}
+
+static void mempool_free_vp(void *element, void *pool_data)
+{
+ size_t size = (size_t) pool_data;
+
+ vpfree(element, size);
+}
+
+static void *mempool_alloc_vp(gfp_t gfp_mask, void *pool_data)
+{
+ size_t size = (size_t) pool_data;
+
+ return vpmalloc(size, gfp_mask);
+}
+
+int mempool_init_kvpmalloc_pool(mempool_t *pool, int min_nr, size_t size)
+{
+ return size < PAGE_SIZE
+ ? mempool_init_kmalloc_pool(pool, min_nr, size)
+ : mempool_init(pool, min_nr, mempool_alloc_vp,
+ mempool_free_vp, (void *) size);
+}
+
+#if 0
+void eytzinger1_test(void)
+{
+ unsigned inorder, eytz, size;
+
+ pr_info("1 based eytzinger test:");
+
+ for (size = 2;
+ size < 65536;
+ size++) {
+ unsigned extra = eytzinger1_extra(size);
+
+ if (!(size % 4096))
+ pr_info("tree size %u", size);
+
+ BUG_ON(eytzinger1_prev(0, size) != eytzinger1_last(size));
+ BUG_ON(eytzinger1_next(0, size) != eytzinger1_first(size));
+
+ BUG_ON(eytzinger1_prev(eytzinger1_first(size), size) != 0);
+ BUG_ON(eytzinger1_next(eytzinger1_last(size), size) != 0);
+
+ inorder = 1;
+ eytzinger1_for_each(eytz, size) {
+ BUG_ON(__inorder_to_eytzinger1(inorder, size, extra) != eytz);
+ BUG_ON(__eytzinger1_to_inorder(eytz, size, extra) != inorder);
+ BUG_ON(eytz != eytzinger1_last(size) &&
+ eytzinger1_prev(eytzinger1_next(eytz, size), size) != eytz);
+
+ inorder++;
+ }
+ }
+}
+
+void eytzinger0_test(void)
+{
+
+ unsigned inorder, eytz, size;
+
+ pr_info("0 based eytzinger test:");
+
+ for (size = 1;
+ size < 65536;
+ size++) {
+ unsigned extra = eytzinger0_extra(size);
+
+ if (!(size % 4096))
+ pr_info("tree size %u", size);
+
+ BUG_ON(eytzinger0_prev(-1, size) != eytzinger0_last(size));
+ BUG_ON(eytzinger0_next(-1, size) != eytzinger0_first(size));
+
+ BUG_ON(eytzinger0_prev(eytzinger0_first(size), size) != -1);
+ BUG_ON(eytzinger0_next(eytzinger0_last(size), size) != -1);
+
+ inorder = 0;
+ eytzinger0_for_each(eytz, size) {
+ BUG_ON(__inorder_to_eytzinger0(inorder, size, extra) != eytz);
+ BUG_ON(__eytzinger0_to_inorder(eytz, size, extra) != inorder);
+ BUG_ON(eytz != eytzinger0_last(size) &&
+ eytzinger0_prev(eytzinger0_next(eytz, size), size) != eytz);
+
+ inorder++;
+ }
+ }
+}
+
+static inline int cmp_u16(const void *_l, const void *_r, size_t size)
+{
+ const u16 *l = _l, *r = _r;
+
+ return (*l > *r) - (*r - *l);
+}
+
+static void eytzinger0_find_test_val(u16 *test_array, unsigned nr, u16 search)
+{
+ int i, c1 = -1, c2 = -1;
+ ssize_t r;
+
+ r = eytzinger0_find_le(test_array, nr,
+ sizeof(test_array[0]),
+ cmp_u16, &search);
+ if (r >= 0)
+ c1 = test_array[r];
+
+ for (i = 0; i < nr; i++)
+ if (test_array[i] <= search && test_array[i] > c2)
+ c2 = test_array[i];
+
+ if (c1 != c2) {
+ eytzinger0_for_each(i, nr)
+ pr_info("[%3u] = %12u", i, test_array[i]);
+ pr_info("find_le(%2u) -> [%2zi] = %2i should be %2i",
+ i, r, c1, c2);
+ }
+}
+
+void eytzinger0_find_test(void)
+{
+ unsigned i, nr, allocated = 1 << 12;
+ u16 *test_array = kmalloc_array(allocated, sizeof(test_array[0]), GFP_KERNEL);
+
+ for (nr = 1; nr < allocated; nr++) {
+ pr_info("testing %u elems", nr);
+
+ get_random_bytes(test_array, nr * sizeof(test_array[0]));
+ eytzinger0_sort(test_array, nr, sizeof(test_array[0]), cmp_u16, NULL);
+
+ /* verify array is sorted correctly: */
+ eytzinger0_for_each(i, nr)
+ BUG_ON(i != eytzinger0_last(nr) &&
+ test_array[i] > test_array[eytzinger0_next(i, nr)]);
+
+ for (i = 0; i < U16_MAX; i += 1 << 12)
+ eytzinger0_find_test_val(test_array, nr, i);
+
+ for (i = 0; i < nr; i++) {
+ eytzinger0_find_test_val(test_array, nr, test_array[i] - 1);
+ eytzinger0_find_test_val(test_array, nr, test_array[i]);
+ eytzinger0_find_test_val(test_array, nr, test_array[i] + 1);
+ }
+ }
+
+ kfree(test_array);
+}
+#endif
+
+/*
+ * Accumulate percpu counters onto one cpu's copy - only valid when access
+ * against any percpu counter is guarded against
+ */
+u64 *bch2_acc_percpu_u64s(u64 __percpu *p, unsigned nr)
+{
+ u64 *ret;
+ int cpu;
+
+ /* access to pcpu vars has to be blocked by other locking */
+ preempt_disable();
+ ret = this_cpu_ptr(p);
+ preempt_enable();
+
+ for_each_possible_cpu(cpu) {
+ u64 *i = per_cpu_ptr(p, cpu);
+
+ if (i != ret) {
+ acc_u64s(ret, i, nr);
+ memset(i, 0, nr * sizeof(u64));
+ }
+ }
+
+ return ret;
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-10 07:42:07 +0000