xref: /openbmc/linux/fs/ceph/metric.c (revision 95298d63)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 
3 #include <linux/types.h>
4 #include <linux/percpu_counter.h>
5 #include <linux/math64.h>
6 
7 #include "metric.h"
8 
9 int ceph_metric_init(struct ceph_client_metric *m)
10 {
11 	int ret;
12 
13 	if (!m)
14 		return -EINVAL;
15 
16 	atomic64_set(&m->total_dentries, 0);
17 	ret = percpu_counter_init(&m->d_lease_hit, 0, GFP_KERNEL);
18 	if (ret)
19 		return ret;
20 
21 	ret = percpu_counter_init(&m->d_lease_mis, 0, GFP_KERNEL);
22 	if (ret)
23 		goto err_d_lease_mis;
24 
25 	ret = percpu_counter_init(&m->i_caps_hit, 0, GFP_KERNEL);
26 	if (ret)
27 		goto err_i_caps_hit;
28 
29 	ret = percpu_counter_init(&m->i_caps_mis, 0, GFP_KERNEL);
30 	if (ret)
31 		goto err_i_caps_mis;
32 
33 	spin_lock_init(&m->read_latency_lock);
34 	m->read_latency_sq_sum = 0;
35 	m->read_latency_min = KTIME_MAX;
36 	m->read_latency_max = 0;
37 	m->total_reads = 0;
38 	m->read_latency_sum = 0;
39 
40 	spin_lock_init(&m->write_latency_lock);
41 	m->write_latency_sq_sum = 0;
42 	m->write_latency_min = KTIME_MAX;
43 	m->write_latency_max = 0;
44 	m->total_writes = 0;
45 	m->write_latency_sum = 0;
46 
47 	spin_lock_init(&m->metadata_latency_lock);
48 	m->metadata_latency_sq_sum = 0;
49 	m->metadata_latency_min = KTIME_MAX;
50 	m->metadata_latency_max = 0;
51 	m->total_metadatas = 0;
52 	m->metadata_latency_sum = 0;
53 
54 	return 0;
55 
56 err_i_caps_mis:
57 	percpu_counter_destroy(&m->i_caps_hit);
58 err_i_caps_hit:
59 	percpu_counter_destroy(&m->d_lease_mis);
60 err_d_lease_mis:
61 	percpu_counter_destroy(&m->d_lease_hit);
62 
63 	return ret;
64 }
65 
66 void ceph_metric_destroy(struct ceph_client_metric *m)
67 {
68 	if (!m)
69 		return;
70 
71 	percpu_counter_destroy(&m->i_caps_mis);
72 	percpu_counter_destroy(&m->i_caps_hit);
73 	percpu_counter_destroy(&m->d_lease_mis);
74 	percpu_counter_destroy(&m->d_lease_hit);
75 }
76 
77 static inline void __update_latency(ktime_t *totalp, ktime_t *lsump,
78 				    ktime_t *min, ktime_t *max,
79 				    ktime_t *sq_sump, ktime_t lat)
80 {
81 	ktime_t total, avg, sq, lsum;
82 
83 	total = ++(*totalp);
84 	lsum = (*lsump += lat);
85 
86 	if (unlikely(lat < *min))
87 		*min = lat;
88 	if (unlikely(lat > *max))
89 		*max = lat;
90 
91 	if (unlikely(total == 1))
92 		return;
93 
94 	/* the sq is (lat - old_avg) * (lat - new_avg) */
95 	avg = DIV64_U64_ROUND_CLOSEST((lsum - lat), (total - 1));
96 	sq = lat - avg;
97 	avg = DIV64_U64_ROUND_CLOSEST(lsum, total);
98 	sq = sq * (lat - avg);
99 	*sq_sump += sq;
100 }
101 
102 void ceph_update_read_latency(struct ceph_client_metric *m,
103 			      ktime_t r_start, ktime_t r_end,
104 			      int rc)
105 {
106 	ktime_t lat = ktime_sub(r_end, r_start);
107 
108 	if (unlikely(rc < 0 && rc != -ENOENT && rc != -ETIMEDOUT))
109 		return;
110 
111 	spin_lock(&m->read_latency_lock);
112 	__update_latency(&m->total_reads, &m->read_latency_sum,
113 			 &m->read_latency_min, &m->read_latency_max,
114 			 &m->read_latency_sq_sum, lat);
115 	spin_unlock(&m->read_latency_lock);
116 }
117 
118 void ceph_update_write_latency(struct ceph_client_metric *m,
119 			       ktime_t r_start, ktime_t r_end,
120 			       int rc)
121 {
122 	ktime_t lat = ktime_sub(r_end, r_start);
123 
124 	if (unlikely(rc && rc != -ETIMEDOUT))
125 		return;
126 
127 	spin_lock(&m->write_latency_lock);
128 	__update_latency(&m->total_writes, &m->write_latency_sum,
129 			 &m->write_latency_min, &m->write_latency_max,
130 			 &m->write_latency_sq_sum, lat);
131 	spin_unlock(&m->write_latency_lock);
132 }
133 
134 void ceph_update_metadata_latency(struct ceph_client_metric *m,
135 				  ktime_t r_start, ktime_t r_end,
136 				  int rc)
137 {
138 	ktime_t lat = ktime_sub(r_end, r_start);
139 
140 	if (unlikely(rc && rc != -ENOENT))
141 		return;
142 
143 	spin_lock(&m->metadata_latency_lock);
144 	__update_latency(&m->total_metadatas, &m->metadata_latency_sum,
145 			 &m->metadata_latency_min, &m->metadata_latency_max,
146 			 &m->metadata_latency_sq_sum, lat);
147 	spin_unlock(&m->metadata_latency_lock);
148 }
149