+// SPDX-License-Identifier: GPL-2.0
/*
* random utiility code, for bcache but in theory not specific to bcache
*
#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/string.h>
#include <linux/types.h>
#include <linux/sched/clock.h>
+#include <linux/mean_and_variance.h>
#include "eytzinger.h"
#include "util.h"
-#define simple_strtoint(c, end, base) simple_strtol(c, end, base)
-#define simple_strtouint(c, end, base) simple_strtoul(c, end, base)
-
static const char si_units[] = "?kMGTPEZY";
-static int __bch2_strtoh(const char *cp, u64 *res,
- u64 t_max, bool t_signed)
+/* 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)
{
- bool positive = *cp != '-';
- unsigned u;
+ const char *start = cp;
u64 v = 0;
- if (*cp == '+' || *cp == '-')
- cp++;
-
if (!isdigit(*cp))
return -EINVAL;
cp++;
} while (isdigit(*cp));
- for (u = 1; u < ARRAY_SIZE(si_units); u++)
+ *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;
}
- u = 0;
+
+ 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:
- if (*cp == '\n')
+ 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++;
- if (*cp)
- return -EINVAL;
+ ret = parse_u64(cp, &f_n);
+ if (ret < 0)
+ return ret;
+ cp += ret;
+
+ ret = bch2_pow(10, ret, &f_d);
+ if (ret)
+ return ret;
+ }
- if (fls64(v) + u * 10 > 64)
+ 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;
- v <<= u * 10;
+ 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)
#define STRTO_H(name, type) \
int bch2_ ## name ## _h(const char *cp, type *res) \
{ \
- u64 v; \
+ u64 v = 0; \
int ret = __bch2_strtoh(cp, &v, ANYSINT_MAX(type), \
ANYSINT_MAX(type) != ((type) ~0ULL)); \
*res = v; \
STRTO_H(strtouint, unsigned int)
STRTO_H(strtoll, long long)
STRTO_H(strtoull, unsigned long long)
-
-ssize_t bch2_hprint(char *buf, s64 v)
-{
- char dec[4] = "";
- int u, t = 0;
-
- for (u = 0; v >= 1024 || v <= -1024; u++) {
- t = v & ~(~0U << 10);
- v >>= 10;
- }
-
- if (!u)
- return sprintf(buf, "%lli", v);
-
- /*
- * 103 is magic: t is in the range [-1023, 1023] and we want
- * to turn it into [-9, 9]
- */
- if (v < 100 && v > -100)
- scnprintf(dec, sizeof(dec), ".%i", t / 103);
-
- return sprintf(buf, "%lli%s%c", v, dec, si_units[u]);
-}
-
-ssize_t bch2_scnprint_string_list(char *buf, size_t size,
- const char * const list[],
- size_t selected)
-{
- char *out = buf;
- size_t i;
-
- if (size)
- *out = '\0';
-
- for (i = 0; list[i]; i++)
- out += scnprintf(out, buf + size - out,
- i == selected ? "[%s] " : "%s ", list[i]);
-
- if (out != buf)
- *--out = '\0';
-
- return out - buf;
-}
-
-ssize_t bch2_scnprint_flag_list(char *buf, size_t size,
- const char * const list[], u64 flags)
-{
- char *out = buf, *end = buf + size;
- unsigned bit, nr = 0;
-
- while (list[nr])
- nr++;
-
- if (size)
- *out = '\0';
-
- while (flags && (bit = __ffs(flags)) < nr) {
- out += scnprintf(out, end - out, "%s,", list[bit]);
- flags ^= 1 << bit;
- }
-
- if (out != buf)
- *--out = '\0';
-
- return out - buf;
-}
+STRTO_H(strtou64, u64)
u64 bch2_read_flag_list(char *opt, const char * const list[])
{
u64 ret = 0;
- char *p, *s, *d = kstrndup(opt, PAGE_SIZE - 1, GFP_KERNEL);
+ char *p, *s, *d = kstrdup(opt, GFP_KERNEL);
if (!d)
return -ENOMEM;
}
}
-/* time stats: */
+void bch2_prt_u64_binary(struct printbuf *out, u64 v, unsigned nr_bits)
+{
+ while (nr_bits)
+ prt_char(out, '0' + ((v >> --nr_bits) & 1));
+}
-static void bch2_time_stats_update_one(struct time_stats *stats,
- u64 start, u64 end)
+void bch2_print_string_as_lines(const char *prefix, const char *lines)
{
- u64 duration, freq;
+ const char *p;
- duration = time_after64(end, start)
- ? end - start : 0;
- freq = time_after64(end, stats->last_event)
- ? end - stats->last_event : 0;
+ if (!lines) {
+ printk("%s (null)\n", prefix);
+ return;
+ }
- stats->count++;
+ console_lock();
+ while (1) {
+ p = strchrnul(lines, '\n');
+ printk("%s%.*s\n", prefix, (int) (p - lines), lines);
+ if (!*p)
+ break;
+ lines = p + 1;
+ prefix = KERN_CONT;
+ }
+ console_unlock();
+}
- stats->average_duration = stats->average_duration
- ? ewma_add(stats->average_duration, duration, 6)
- : duration;
+int bch2_prt_backtrace(struct printbuf *out, struct task_struct *task)
+{
+ unsigned long entries[32];
+ unsigned i, nr_entries;
+ int ret;
+
+ ret = down_read_killable(&task->signal->exec_update_lock);
+ if (ret)
+ return ret;
+
+ nr_entries = stack_trace_save_tsk(task, entries, ARRAY_SIZE(entries), 0);
+ for (i = 0; i < nr_entries; i++) {
+ prt_printf(out, "[<0>] %pB", (void *)entries[i]);
+ prt_newline(out);
+ }
- stats->average_frequency = stats->average_frequency
- ? ewma_add(stats->average_frequency, freq, 6)
- : freq;
+ up_read(&task->signal->exec_update_lock);
+ return 0;
+}
- stats->max_duration = max(stats->max_duration, duration);
+/* time stats: */
- stats->last_event = end;
+static inline void bch2_time_stats_update_one(struct time_stats *stats,
+ u64 start, u64 end)
+{
+ u64 duration, freq;
- bch2_quantiles_update(&stats->quantiles, duration);
+ if (time_after64(end, start)) {
+ duration = end - start;
+ stats->duration_stats = mean_and_variance_update_inlined(stats->duration_stats,
+ duration);
+ stats->duration_stats_weighted = 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 (time_after64(end, stats->last_event)) {
+ freq = end - stats->last_event;
+ stats->freq_stats = mean_and_variance_update_inlined(stats->freq_stats, freq);
+ stats->freq_stats_weighted = 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 time_stats *stats,
+ struct time_stat_buffer *b)
+{
+ struct 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 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 (stats->average_frequency < 32 &&
- stats->count > 1024)
+ if (mean_and_variance_weighted_get_mean(stats->freq_stats_weighted) < 32 &&
+ stats->duration_stats.n > 1024)
stats->buffer =
alloc_percpu_gfp(struct time_stat_buffer,
GFP_ATOMIC);
spin_unlock_irqrestore(&stats->lock, flags);
} else {
- struct time_stat_buffer_entry *i;
struct time_stat_buffer *b;
preempt_disable();
.end = end
};
- if (b->nr == ARRAY_SIZE(b->entries)) {
- 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;
- }
-
+ if (unlikely(b->nr == ARRAY_SIZE(b->entries)))
+ bch2_time_stats_clear_buffer(stats, b);
preempt_enable();
}
}
static const struct time_unit {
const char *name;
- u32 nsecs;
+ u64 nsecs;
} time_units[] = {
- { "ns", 1 },
- { "us", NSEC_PER_USEC },
- { "ms", NSEC_PER_MSEC },
- { "sec", NSEC_PER_SEC },
+ { "ns", 1 },
+ { "us", NSEC_PER_USEC },
+ { "ms", NSEC_PER_MSEC },
+ { "s", NSEC_PER_SEC },
+ { "m", NSEC_PER_SEC * 60},
+ { "h", NSEC_PER_SEC * 3600},
+ { "eon", U64_MAX },
};
static const struct time_unit *pick_time_units(u64 ns)
return u;
}
-static size_t pr_time_units(char *buf, size_t len, u64 ns)
+static void pr_time_units(struct printbuf *out, u64 ns)
{
const struct time_unit *u = pick_time_units(ns);
- return scnprintf(buf, len, "%llu %s", div_u64(ns, u->nsecs), u->name);
+ prt_printf(out, "%llu ", div64_u64(ns, u->nsecs));
+ prt_tab_rjust(out);
+ prt_printf(out, "%s", u->name);
+}
+
+#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);
+ pr_time_units(out, ns);
+ prt_newline(out);
}
-size_t bch2_time_stats_print(struct time_stats *stats, char *buf, size_t len)
+void bch2_time_stats_to_text(struct printbuf *out, struct time_stats *stats)
{
- char *out = buf, *end = buf + len;
const struct time_unit *u;
- u64 freq = READ_ONCE(stats->average_frequency);
- u64 q, last_q = 0;
+ 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);
+ }
- out += scnprintf(out, end - out, "count:\t\t%llu\n",
- stats->count);
- out += scnprintf(out, end - out, "rate:\t\t%llu/sec\n",
- freq ? div64_u64(NSEC_PER_SEC, freq) : 0);
-
- out += scnprintf(out, end - out, "frequency:\t");
- out += pr_time_units(out, end - out, freq);
-
- out += scnprintf(out, end - out, "\navg duration:\t");
- out += pr_time_units(out, end - out, stats->average_duration);
-
- out += scnprintf(out, end - out, "\nmax duration:\t");
- out += pr_time_units(out, end - out, stats->max_duration);
+ 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);
+ pr_time_units(out, d_mean);
+ prt_tab(out);
+ pr_time_units(out, mean_and_variance_weighted_get_mean(stats->duration_stats_weighted));
+ prt_newline(out);
+
+ prt_printf(out, "stddev:");
+ prt_tab(out);
+ pr_time_units(out, d_stddev);
+ prt_tab(out);
+ pr_time_units(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);
+ pr_time_units(out, f_mean);
+ prt_tab(out);
+ pr_time_units(out, mean_and_variance_weighted_get_mean(stats->freq_stats_weighted));
+ prt_newline(out);
+
+ prt_printf(out, "stddev:");
+ prt_tab(out);
+ pr_time_units(out, f_stddev);
+ prt_tab(out);
+ pr_time_units(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);
- out += scnprintf(out, end - out, "\nquantiles (%s):\t", u->name);
+ 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);
- out += scnprintf(out, end - out, "%llu%s",
- div_u64(q, u->nsecs),
- is_last ? "\n" : " ");
+ prt_printf(out, "%llu ",
+ div_u64(q, u->nsecs));
+ if (is_last)
+ prt_newline(out);
last_q = q;
}
-
- return out - buf;
}
void bch2_time_stats_exit(struct time_stats *stats)
void bch2_time_stats_init(struct time_stats *stats)
{
memset(stats, 0, sizeof(*stats));
+ stats->duration_stats_weighted.w = 8;
+ stats->freq_stats_weighted.w = 8;
+ stats->min_duration = U64_MAX;
+ stats->min_freq = U64_MAX;
spin_lock_init(&stats->lock);
}
d->next = now - NSEC_PER_SEC * 2;
}
-int bch2_ratelimit_wait_freezable_stoppable(struct bch_ratelimit *d)
-{
- bool kthread = (current->flags & PF_KTHREAD) != 0;
-
- while (1) {
- u64 delay = bch2_ratelimit_delay(d);
-
- if (delay)
- set_current_state(TASK_INTERRUPTIBLE);
-
- if (kthread && kthread_should_stop())
- return 1;
-
- if (!delay)
- return 0;
-
- schedule_timeout(delay);
- try_to_freeze();
- }
-}
-
/* pd controller: */
/*
pd->backpressure = 1;
}
-size_t bch2_pd_controller_print_debug(struct bch_pd_controller *pd, char *buf)
+void bch2_pd_controller_debug_to_text(struct printbuf *out, struct bch_pd_controller *pd)
{
- /* 2^64 - 1 is 20 digits, plus null byte */
- char rate[21];
- char actual[21];
- char target[21];
- char proportional[21];
- char derivative[21];
- char change[21];
- s64 next_io;
-
- bch2_hprint(rate, pd->rate.rate);
- bch2_hprint(actual, pd->last_actual);
- bch2_hprint(target, pd->last_target);
- bch2_hprint(proportional, pd->last_proportional);
- bch2_hprint(derivative, pd->last_derivative);
- bch2_hprint(change, pd->last_change);
-
- next_io = div64_s64(pd->rate.next - local_clock(), NSEC_PER_MSEC);
-
- return sprintf(buf,
- "rate:\t\t%s/sec\n"
- "target:\t\t%s\n"
- "actual:\t\t%s\n"
- "proportional:\t%s\n"
- "derivative:\t%s\n"
- "change:\t\t%s/sec\n"
- "next io:\t%llims\n",
- rate, target, actual, proportional,
- derivative, change, next_io);
+ 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)
+void bch2_bio_map(struct bio *bio, void *base, size_t size)
{
- size_t size = bio->bi_iter.bi_size;
- struct bio_vec *bv = bio->bi_io_vec;
-
- BUG_ON(!bio->bi_iter.bi_size);
- BUG_ON(bio->bi_vcnt);
-
- bv->bv_offset = base ? offset_in_page(base) : 0;
- goto start;
-
- for (; size; bio->bi_vcnt++, bv++) {
- bv->bv_offset = 0;
-start: bv->bv_len = min_t(size_t, PAGE_SIZE - bv->bv_offset,
- size);
- BUG_ON(bio->bi_vcnt >= bio->bi_max_vecs);
- if (base) {
- bv->bv_page = is_vmalloc_addr(base)
+ 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);
- base += bv->bv_len;
- }
-
- size -= bv->bv_len;
+ BUG_ON(!bio_add_page(bio, page, len, offset));
+ size -= len;
+ base += len;
}
}
-int bch2_bio_alloc_pages(struct bio *bio, gfp_t gfp_mask)
+int bch2_bio_alloc_pages(struct bio *bio, size_t size, gfp_t gfp_mask)
{
- int i;
- struct bio_vec *bv;
+ while (size) {
+ struct page *page = alloc_page(gfp_mask);
+ unsigned len = min_t(size_t, PAGE_SIZE, size);
- bio_for_each_segment_all(bv, bio, i) {
- bv->bv_page = alloc_page(gfp_mask);
- if (!bv->bv_page) {
- while (--bv >= bio->bi_io_vec)
- __free_page(bv->bv_page);
+ if (!page)
return -ENOMEM;
+
+ if (unlikely(!bio_add_page(bio, page, len, 0))) {
+ __free_page(page);
+ break;
}
+
+ size -= len;
}
return 0;
return rand;
}
-void memcpy_to_bio(struct bio *dst, struct bvec_iter dst_iter, void *src)
+void memcpy_to_bio(struct bio *dst, struct bvec_iter dst_iter, const void *src)
{
struct bio_vec bv;
struct bvec_iter iter;
}
}
-size_t bch_scnmemcpy(char *buf, size_t size, const char *src, size_t len)
-{
- size_t n;
-
- if (!size)
- return 0;
-
- n = min(size - 1, len);
- memcpy(buf, src, n);
- buf[n] = '\0';
-
- return n;
-}
-
-#include "eytzinger.h"
-
static int alignment_ok(const void *base, size_t align)
{
return IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) ||
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;
+}
projects / bcachefs-tools-debian / blobdiff