Commit | Line | Data |
---|---|---|
02bcaa8c | 1 | /* |
f5cc024a | 2 | * Clock functions |
02bcaa8c | 3 | */ |
f5cc024a | 4 | |
02bcaa8c | 5 | #include <unistd.h> |
c223da83 | 6 | #include <math.h> |
02bcaa8c JA |
7 | #include <sys/time.h> |
8 | ||
9 | #include "fio.h" | |
be4ecfdf | 10 | #include "smalloc.h" |
02bcaa8c JA |
11 | |
12 | #include "hash.h" | |
13 | ||
c223da83 | 14 | static unsigned long cycles_per_usec; |
3e488920 | 15 | static struct timeval last_tv; |
c223da83 | 16 | static unsigned long last_cycles; |
3e488920 | 17 | static int last_tv_valid; |
02bcaa8c | 18 | |
be4ecfdf JA |
19 | static struct timeval *fio_tv; |
20 | int fio_gtod_offload = 0; | |
21 | int fio_gtod_cpu = -1; | |
22 | ||
c223da83 JA |
23 | enum fio_cs fio_clock_source = CS_GTOD; |
24 | ||
02bcaa8c JA |
25 | #ifdef FIO_DEBUG_TIME |
26 | ||
27 | #define HASH_BITS 8 | |
28 | #define HASH_SIZE (1 << HASH_BITS) | |
29 | ||
01743ee1 | 30 | static struct flist_head hash[HASH_SIZE]; |
02bcaa8c JA |
31 | static int gtod_inited; |
32 | ||
33 | struct gtod_log { | |
01743ee1 | 34 | struct flist_head list; |
02bcaa8c JA |
35 | void *caller; |
36 | unsigned long calls; | |
37 | }; | |
38 | ||
39 | static struct gtod_log *find_hash(void *caller) | |
40 | { | |
41 | unsigned long h = hash_ptr(caller, HASH_BITS); | |
01743ee1 | 42 | struct flist_head *entry; |
02bcaa8c | 43 | |
01743ee1 JA |
44 | flist_for_each(entry, &hash[h]) { |
45 | struct gtod_log *log = flist_entry(entry, struct gtod_log, | |
46 | list); | |
02bcaa8c JA |
47 | |
48 | if (log->caller == caller) | |
49 | return log; | |
50 | } | |
51 | ||
52 | return NULL; | |
53 | } | |
54 | ||
55 | static struct gtod_log *find_log(void *caller) | |
56 | { | |
57 | struct gtod_log *log = find_hash(caller); | |
58 | ||
59 | if (!log) { | |
60 | unsigned long h; | |
61 | ||
62 | log = malloc(sizeof(*log)); | |
01743ee1 | 63 | INIT_FLIST_HEAD(&log->list); |
02bcaa8c JA |
64 | log->caller = caller; |
65 | log->calls = 0; | |
66 | ||
67 | h = hash_ptr(caller, HASH_BITS); | |
01743ee1 | 68 | flist_add_tail(&log->list, &hash[h]); |
02bcaa8c JA |
69 | } |
70 | ||
71 | return log; | |
72 | } | |
73 | ||
74 | static void gtod_log_caller(void *caller) | |
75 | { | |
76 | if (gtod_inited) { | |
77 | struct gtod_log *log = find_log(caller); | |
78 | ||
79 | log->calls++; | |
80 | } | |
81 | } | |
82 | ||
83 | static void fio_exit fio_dump_gtod(void) | |
84 | { | |
85 | unsigned long total_calls = 0; | |
86 | int i; | |
87 | ||
88 | for (i = 0; i < HASH_SIZE; i++) { | |
01743ee1 | 89 | struct flist_head *entry; |
02bcaa8c JA |
90 | struct gtod_log *log; |
91 | ||
01743ee1 JA |
92 | flist_for_each(entry, &hash[i]) { |
93 | log = flist_entry(entry, struct gtod_log, list); | |
02bcaa8c | 94 | |
5ec10eaa JA |
95 | printf("function %p, calls %lu\n", log->caller, |
96 | log->calls); | |
02bcaa8c JA |
97 | total_calls += log->calls; |
98 | } | |
99 | } | |
100 | ||
101 | printf("Total %lu gettimeofday\n", total_calls); | |
102 | } | |
103 | ||
104 | static void fio_init gtod_init(void) | |
105 | { | |
106 | int i; | |
107 | ||
108 | for (i = 0; i < HASH_SIZE; i++) | |
01743ee1 | 109 | INIT_FLIST_HEAD(&hash[i]); |
02bcaa8c JA |
110 | |
111 | gtod_inited = 1; | |
112 | } | |
113 | ||
114 | #endif /* FIO_DEBUG_TIME */ | |
115 | ||
1e97cce9 | 116 | #ifdef FIO_DEBUG_TIME |
02bcaa8c | 117 | void fio_gettime(struct timeval *tp, void *caller) |
1e97cce9 JA |
118 | #else |
119 | void fio_gettime(struct timeval *tp, void fio_unused *caller) | |
120 | #endif | |
02bcaa8c JA |
121 | { |
122 | #ifdef FIO_DEBUG_TIME | |
123 | if (!caller) | |
124 | caller = __builtin_return_address(0); | |
125 | ||
126 | gtod_log_caller(caller); | |
02bcaa8c | 127 | #endif |
be4ecfdf JA |
128 | if (fio_tv) { |
129 | memcpy(tp, fio_tv, sizeof(*tp)); | |
130 | return; | |
c223da83 JA |
131 | } |
132 | ||
133 | switch (fio_clock_source) { | |
134 | case CS_GTOD: | |
02bcaa8c | 135 | gettimeofday(tp, NULL); |
c223da83 JA |
136 | break; |
137 | case CS_CGETTIME: { | |
02bcaa8c JA |
138 | struct timespec ts; |
139 | ||
d481e006 | 140 | if (clock_gettime(CLOCK_REALTIME, &ts) < 0) { |
c223da83 JA |
141 | log_err("fio: clock_gettime fails\n"); |
142 | assert(0); | |
02bcaa8c JA |
143 | } |
144 | ||
145 | tp->tv_sec = ts.tv_sec; | |
146 | tp->tv_usec = ts.tv_nsec / 1000; | |
c223da83 JA |
147 | break; |
148 | } | |
149 | #ifdef ARCH_HAVE_CPU_CLOCK | |
150 | case CS_CPUCLOCK: { | |
151 | unsigned long long usecs, t; | |
152 | ||
153 | t = get_cpu_clock(); | |
154 | if (t < last_cycles) { | |
155 | dprint(FD_TIME, "CPU clock going back in time\n"); | |
156 | t = last_cycles; | |
157 | } | |
158 | ||
159 | usecs = t / cycles_per_usec; | |
160 | tp->tv_sec = usecs / 1000000; | |
161 | tp->tv_usec = usecs % 1000000; | |
162 | last_cycles = t; | |
163 | break; | |
164 | } | |
165 | #endif | |
166 | default: | |
167 | log_err("fio: invalid clock source %d\n", fio_clock_source); | |
168 | break; | |
02bcaa8c | 169 | } |
3e488920 JA |
170 | |
171 | /* | |
172 | * If Linux is using the tsc clock on non-synced processors, | |
173 | * sometimes time can appear to drift backwards. Fix that up. | |
174 | */ | |
175 | if (last_tv_valid) { | |
176 | if (tp->tv_sec < last_tv.tv_sec) | |
177 | tp->tv_sec = last_tv.tv_sec; | |
178 | else if (last_tv.tv_sec == tp->tv_sec && | |
179 | tp->tv_usec < last_tv.tv_usec) | |
180 | tp->tv_usec = last_tv.tv_usec; | |
181 | } | |
182 | last_tv_valid = 1; | |
183 | memcpy(&last_tv, tp, sizeof(*tp)); | |
02bcaa8c | 184 | } |
be4ecfdf | 185 | |
c223da83 JA |
186 | static unsigned long get_cycles_per_usec(void) |
187 | { | |
188 | struct timeval s, e; | |
189 | unsigned long long c_s, c_e; | |
190 | ||
191 | gettimeofday(&s, NULL); | |
192 | c_s = get_cpu_clock(); | |
193 | do { | |
194 | unsigned long long elapsed; | |
195 | ||
196 | gettimeofday(&e, NULL); | |
197 | elapsed = utime_since(&s, &e); | |
198 | if (elapsed >= 10) { | |
199 | c_e = get_cpu_clock(); | |
200 | break; | |
201 | } | |
202 | } while (1); | |
203 | ||
204 | return c_e - c_s; | |
205 | } | |
206 | ||
207 | void fio_clock_init(void) | |
208 | { | |
209 | double delta, mean, S; | |
210 | unsigned long avg, cycles[10]; | |
211 | int i, samples; | |
212 | ||
213 | last_tv_valid = 0; | |
214 | ||
215 | cycles[0] = get_cycles_per_usec(); | |
216 | S = delta = mean = 0.0; | |
217 | for (i = 0; i < 10; i++) { | |
218 | cycles[i] = get_cycles_per_usec(); | |
219 | delta = cycles[i] - mean; | |
220 | if (delta) { | |
221 | mean += delta / (i + 1.0); | |
222 | S += delta * (cycles[i] - mean); | |
223 | } | |
224 | } | |
225 | ||
226 | S = sqrt(S / (10 - 1.0)); | |
227 | ||
228 | samples = avg = 0; | |
229 | for (i = 0; i < 10; i++) { | |
230 | double this = cycles[i]; | |
231 | ||
232 | if ((max(this, mean) - min(this, mean)) > S) | |
233 | continue; | |
234 | samples++; | |
235 | avg += this; | |
236 | } | |
237 | ||
238 | S /= 10.0; | |
239 | mean /= 10.0; | |
240 | ||
241 | for (i = 0; i < 10; i++) | |
242 | dprint(FD_TIME, "cycles[%d]=%lu\n", i, cycles[i] / 10); | |
243 | ||
244 | avg /= (samples * 10); | |
245 | dprint(FD_TIME, "avg: %lu\n", avg); | |
246 | dprint(FD_TIME, "mean=%f, S=%f\n", mean, S); | |
247 | ||
248 | cycles_per_usec = avg; | |
249 | } | |
250 | ||
be4ecfdf JA |
251 | void fio_gtod_init(void) |
252 | { | |
253 | fio_tv = smalloc(sizeof(struct timeval)); | |
254 | assert(fio_tv); | |
255 | } | |
256 | ||
257 | void fio_gtod_update(void) | |
258 | { | |
259 | gettimeofday(fio_tv, NULL); | |
260 | } |