Commit | Line | Data |
---|---|---|
02bcaa8c | 1 | /* |
f5cc024a | 2 | * Clock functions |
02bcaa8c | 3 | */ |
f5cc024a | 4 | |
02bcaa8c | 5 | #include <unistd.h> |
c223da83 | 6 | #include <math.h> |
02bcaa8c | 7 | #include <sys/time.h> |
03e20d68 | 8 | #include <time.h> |
02bcaa8c JA |
9 | |
10 | #include "fio.h" | |
be4ecfdf | 11 | #include "smalloc.h" |
02bcaa8c JA |
12 | |
13 | #include "hash.h" | |
14 | ||
09a32402 | 15 | #ifdef ARCH_HAVE_CPU_CLOCK |
c223da83 | 16 | static unsigned long cycles_per_usec; |
c223da83 | 17 | static unsigned long last_cycles; |
09a32402 JA |
18 | #endif |
19 | static struct timeval last_tv; | |
3e488920 | 20 | static int last_tv_valid; |
02bcaa8c | 21 | |
be4ecfdf JA |
22 | static struct timeval *fio_tv; |
23 | int fio_gtod_offload = 0; | |
24 | int fio_gtod_cpu = -1; | |
25 | ||
c223da83 JA |
26 | enum fio_cs fio_clock_source = CS_GTOD; |
27 | ||
02bcaa8c JA |
28 | #ifdef FIO_DEBUG_TIME |
29 | ||
30 | #define HASH_BITS 8 | |
31 | #define HASH_SIZE (1 << HASH_BITS) | |
32 | ||
01743ee1 | 33 | static struct flist_head hash[HASH_SIZE]; |
02bcaa8c JA |
34 | static int gtod_inited; |
35 | ||
36 | struct gtod_log { | |
01743ee1 | 37 | struct flist_head list; |
02bcaa8c JA |
38 | void *caller; |
39 | unsigned long calls; | |
40 | }; | |
41 | ||
42 | static struct gtod_log *find_hash(void *caller) | |
43 | { | |
44 | unsigned long h = hash_ptr(caller, HASH_BITS); | |
01743ee1 | 45 | struct flist_head *entry; |
02bcaa8c | 46 | |
01743ee1 JA |
47 | flist_for_each(entry, &hash[h]) { |
48 | struct gtod_log *log = flist_entry(entry, struct gtod_log, | |
49 | list); | |
02bcaa8c JA |
50 | |
51 | if (log->caller == caller) | |
52 | return log; | |
53 | } | |
54 | ||
55 | return NULL; | |
56 | } | |
57 | ||
58 | static struct gtod_log *find_log(void *caller) | |
59 | { | |
60 | struct gtod_log *log = find_hash(caller); | |
61 | ||
62 | if (!log) { | |
63 | unsigned long h; | |
64 | ||
65 | log = malloc(sizeof(*log)); | |
01743ee1 | 66 | INIT_FLIST_HEAD(&log->list); |
02bcaa8c JA |
67 | log->caller = caller; |
68 | log->calls = 0; | |
69 | ||
70 | h = hash_ptr(caller, HASH_BITS); | |
01743ee1 | 71 | flist_add_tail(&log->list, &hash[h]); |
02bcaa8c JA |
72 | } |
73 | ||
74 | return log; | |
75 | } | |
76 | ||
77 | static void gtod_log_caller(void *caller) | |
78 | { | |
79 | if (gtod_inited) { | |
80 | struct gtod_log *log = find_log(caller); | |
81 | ||
82 | log->calls++; | |
83 | } | |
84 | } | |
85 | ||
86 | static void fio_exit fio_dump_gtod(void) | |
87 | { | |
88 | unsigned long total_calls = 0; | |
89 | int i; | |
90 | ||
91 | for (i = 0; i < HASH_SIZE; i++) { | |
01743ee1 | 92 | struct flist_head *entry; |
02bcaa8c JA |
93 | struct gtod_log *log; |
94 | ||
01743ee1 JA |
95 | flist_for_each(entry, &hash[i]) { |
96 | log = flist_entry(entry, struct gtod_log, list); | |
02bcaa8c | 97 | |
5ec10eaa JA |
98 | printf("function %p, calls %lu\n", log->caller, |
99 | log->calls); | |
02bcaa8c JA |
100 | total_calls += log->calls; |
101 | } | |
102 | } | |
103 | ||
104 | printf("Total %lu gettimeofday\n", total_calls); | |
105 | } | |
106 | ||
107 | static void fio_init gtod_init(void) | |
108 | { | |
109 | int i; | |
110 | ||
111 | for (i = 0; i < HASH_SIZE; i++) | |
01743ee1 | 112 | INIT_FLIST_HEAD(&hash[i]); |
02bcaa8c JA |
113 | |
114 | gtod_inited = 1; | |
115 | } | |
116 | ||
117 | #endif /* FIO_DEBUG_TIME */ | |
118 | ||
1e97cce9 | 119 | #ifdef FIO_DEBUG_TIME |
02bcaa8c | 120 | void fio_gettime(struct timeval *tp, void *caller) |
1e97cce9 JA |
121 | #else |
122 | void fio_gettime(struct timeval *tp, void fio_unused *caller) | |
123 | #endif | |
02bcaa8c JA |
124 | { |
125 | #ifdef FIO_DEBUG_TIME | |
126 | if (!caller) | |
127 | caller = __builtin_return_address(0); | |
128 | ||
129 | gtod_log_caller(caller); | |
02bcaa8c | 130 | #endif |
be4ecfdf JA |
131 | if (fio_tv) { |
132 | memcpy(tp, fio_tv, sizeof(*tp)); | |
133 | return; | |
c223da83 JA |
134 | } |
135 | ||
136 | switch (fio_clock_source) { | |
137 | case CS_GTOD: | |
02bcaa8c | 138 | gettimeofday(tp, NULL); |
c223da83 JA |
139 | break; |
140 | case CS_CGETTIME: { | |
02bcaa8c JA |
141 | struct timespec ts; |
142 | ||
5bd9c78c JA |
143 | #ifdef FIO_HAVE_CLOCK_MONOTONIC |
144 | if (clock_gettime(CLOCK_MONOTONIC, &ts) < 0) { | |
145 | #else | |
d481e006 | 146 | if (clock_gettime(CLOCK_REALTIME, &ts) < 0) { |
5bd9c78c | 147 | #endif |
c223da83 JA |
148 | log_err("fio: clock_gettime fails\n"); |
149 | assert(0); | |
02bcaa8c JA |
150 | } |
151 | ||
152 | tp->tv_sec = ts.tv_sec; | |
153 | tp->tv_usec = ts.tv_nsec / 1000; | |
c223da83 JA |
154 | break; |
155 | } | |
156 | #ifdef ARCH_HAVE_CPU_CLOCK | |
157 | case CS_CPUCLOCK: { | |
158 | unsigned long long usecs, t; | |
159 | ||
160 | t = get_cpu_clock(); | |
161 | if (t < last_cycles) { | |
162 | dprint(FD_TIME, "CPU clock going back in time\n"); | |
163 | t = last_cycles; | |
164 | } | |
165 | ||
166 | usecs = t / cycles_per_usec; | |
167 | tp->tv_sec = usecs / 1000000; | |
168 | tp->tv_usec = usecs % 1000000; | |
169 | last_cycles = t; | |
170 | break; | |
171 | } | |
172 | #endif | |
173 | default: | |
174 | log_err("fio: invalid clock source %d\n", fio_clock_source); | |
175 | break; | |
02bcaa8c | 176 | } |
3e488920 JA |
177 | |
178 | /* | |
179 | * If Linux is using the tsc clock on non-synced processors, | |
180 | * sometimes time can appear to drift backwards. Fix that up. | |
181 | */ | |
182 | if (last_tv_valid) { | |
183 | if (tp->tv_sec < last_tv.tv_sec) | |
184 | tp->tv_sec = last_tv.tv_sec; | |
185 | else if (last_tv.tv_sec == tp->tv_sec && | |
186 | tp->tv_usec < last_tv.tv_usec) | |
187 | tp->tv_usec = last_tv.tv_usec; | |
188 | } | |
189 | last_tv_valid = 1; | |
190 | memcpy(&last_tv, tp, sizeof(*tp)); | |
02bcaa8c | 191 | } |
be4ecfdf | 192 | |
09a32402 | 193 | #ifdef ARCH_HAVE_CPU_CLOCK |
c223da83 JA |
194 | static unsigned long get_cycles_per_usec(void) |
195 | { | |
196 | struct timeval s, e; | |
197 | unsigned long long c_s, c_e; | |
198 | ||
199 | gettimeofday(&s, NULL); | |
200 | c_s = get_cpu_clock(); | |
201 | do { | |
202 | unsigned long long elapsed; | |
203 | ||
204 | gettimeofday(&e, NULL); | |
205 | elapsed = utime_since(&s, &e); | |
206 | if (elapsed >= 10) { | |
207 | c_e = get_cpu_clock(); | |
208 | break; | |
209 | } | |
210 | } while (1); | |
211 | ||
212 | return c_e - c_s; | |
213 | } | |
214 | ||
09a32402 | 215 | static void calibrate_cpu_clock(void) |
c223da83 JA |
216 | { |
217 | double delta, mean, S; | |
218 | unsigned long avg, cycles[10]; | |
219 | int i, samples; | |
220 | ||
c223da83 JA |
221 | cycles[0] = get_cycles_per_usec(); |
222 | S = delta = mean = 0.0; | |
223 | for (i = 0; i < 10; i++) { | |
224 | cycles[i] = get_cycles_per_usec(); | |
225 | delta = cycles[i] - mean; | |
226 | if (delta) { | |
227 | mean += delta / (i + 1.0); | |
228 | S += delta * (cycles[i] - mean); | |
229 | } | |
230 | } | |
231 | ||
232 | S = sqrt(S / (10 - 1.0)); | |
233 | ||
234 | samples = avg = 0; | |
235 | for (i = 0; i < 10; i++) { | |
236 | double this = cycles[i]; | |
237 | ||
03e20d68 | 238 | if ((fmax(this, mean) - fmin(this, mean)) > S) |
c223da83 JA |
239 | continue; |
240 | samples++; | |
241 | avg += this; | |
242 | } | |
243 | ||
244 | S /= 10.0; | |
245 | mean /= 10.0; | |
246 | ||
247 | for (i = 0; i < 10; i++) | |
248 | dprint(FD_TIME, "cycles[%d]=%lu\n", i, cycles[i] / 10); | |
249 | ||
250 | avg /= (samples * 10); | |
251 | dprint(FD_TIME, "avg: %lu\n", avg); | |
252 | dprint(FD_TIME, "mean=%f, S=%f\n", mean, S); | |
253 | ||
254 | cycles_per_usec = avg; | |
09a32402 JA |
255 | |
256 | } | |
257 | #else | |
258 | static void calibrate_cpu_clock(void) | |
259 | { | |
260 | } | |
261 | #endif | |
262 | ||
263 | void fio_clock_init(void) | |
264 | { | |
265 | last_tv_valid = 0; | |
266 | calibrate_cpu_clock(); | |
c223da83 JA |
267 | } |
268 | ||
be4ecfdf JA |
269 | void fio_gtod_init(void) |
270 | { | |
271 | fio_tv = smalloc(sizeof(struct timeval)); | |
272 | assert(fio_tv); | |
273 | } | |
274 | ||
275 | void fio_gtod_update(void) | |
276 | { | |
277 | gettimeofday(fio_tv, NULL); | |
278 | } |