bcachefs: pull out time_stats.[ch]

prep work for lifting out of fs/bcachefs/

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

1 files changed, 19 insertions, 177 deletions

diff --git a/fs/bcachefs/util.c b/fs/bcachefs/util.c
index bd3687a726f7..96de039fc890 100644
--- a/fs/bcachefs/util.c
+++ b/fs/bcachefs/util.c
@@ -337,157 +337,16 @@ void bch2_prt_datetime(struct printbuf *out, time64_t sec)
 }
 #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);
+	const struct time_unit *u = bch2_pick_time_units(ns);
 
 	prt_printf(out, "%llu %s", div_u64(ns, u->nsecs), u->name);
 }
 
-/* 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);
-		stats->total_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 void __bch2_time_stats_clear_buffer(struct bch2_time_stats *stats,
-					   struct bch2_time_stat_buffer *b)
-{
-	for (struct bch2_time_stat_buffer_entry *i = b->entries;
-	     i < b->entries + ARRAY_SIZE(b->entries);
-	     i++)
-		bch2_time_stats_update_one(stats, i->start, i->end);
-	b->nr = 0;
-}
-
-static noinline void bch2_time_stats_clear_buffer(struct bch2_time_stats *stats,
-						  struct bch2_time_stat_buffer *b)
-{
-	unsigned long flags;
-
-	spin_lock_irqsave(&stats->lock, flags);
-	__bch2_time_stats_clear_buffer(stats, b);
-	spin_unlock_irqrestore(&stats->lock, flags);
-}
-
-void __bch2_time_stats_update(struct bch2_time_stats *stats, u64 start, u64 end)
-{
-	unsigned long flags;
-
-	WARN_ONCE(!stats->duration_stats_weighted.weight ||
-		  !stats->freq_stats_weighted.weight,
-		  "uninitialized time_stats");
-
-	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();
-	}
-}
-
 static void bch2_pr_time_units_aligned(struct printbuf *out, u64 ns)
 {
-	const struct time_unit *u = pick_time_units(ns);
+	const struct time_unit *u = bch2_pick_time_units(ns);
 
 	prt_printf(out, "%llu ", div64_u64(ns, u->nsecs));
 	prt_tab_rjust(out);
@@ -506,10 +365,8 @@ static inline void pr_name_and_units(struct printbuf *out, const char *name, u64
 
 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;
+	u64 f_stddev = 0, d_stddev = 0;
 
 	if (stats->buffer) {
 		int cpu;
@@ -608,39 +465,24 @@ void bch2_time_stats_to_text(struct printbuf *out, struct bch2_time_stats *stats
 
 	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;
+	if (stats->quantiles_enabled) {
+		int i = eytzinger0_first(NR_QUANTILES);
+		const struct time_unit *u =
+			bch2_pick_time_units(stats->quantiles.entries[i].m);
+		u64 last_q = 0;
+
+		prt_printf(out, "quantiles (%s):\t", u->name);
+		eytzinger0_for_each(i, NR_QUANTILES) {
+			bool is_last = eytzinger0_next(i, NR_QUANTILES) == -1;
+
+			u64 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;
+		}
 	}
 }
-#else
-void bch2_time_stats_to_text(struct printbuf *out, struct bch2_time_stats *stats) {}
-#endif
-
-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: */