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