1 | /* |
2 | * include/linux/ktime.h |
3 | * |
4 | * ktime_t - nanosecond-resolution time format. |
5 | * |
6 | * Copyright(C) 2005, Thomas Gleixner <tglx@linutronix.de> |
7 | * Copyright(C) 2005, Red Hat, Inc., Ingo Molnar |
8 | * |
9 | * data type definitions, declarations, prototypes and macros. |
10 | * |
11 | * Started by: Thomas Gleixner and Ingo Molnar |
12 | * |
13 | * Credits: |
14 | * |
15 | * Roman Zippel provided the ideas and primary code snippets of |
16 | * the ktime_t union and further simplifications of the original |
17 | * code. |
18 | * |
19 | * For licencing details see kernel-base/COPYING |
20 | */ |
21 | #ifndef _LINUX_KTIME_H |
22 | #define _LINUX_KTIME_H |
23 | |
24 | #include <linux/time.h> |
25 | #include <linux/jiffies.h> |
26 | |
27 | /* Nanosecond scalar representation for kernel time values */ |
28 | typedef s64 ktime_t; |
29 | |
30 | /** |
31 | * ktime_set - Set a ktime_t variable from a seconds/nanoseconds value |
32 | * @secs: seconds to set |
33 | * @nsecs: nanoseconds to set |
34 | * |
35 | * Return: The ktime_t representation of the value. |
36 | */ |
37 | static inline ktime_t ktime_set(const s64 secs, const unsigned long nsecs) |
38 | { |
39 | if (unlikely(secs >= KTIME_SEC_MAX)) |
40 | return KTIME_MAX; |
41 | |
42 | return secs * NSEC_PER_SEC + (s64)nsecs; |
43 | } |
44 | |
45 | /* Subtract two ktime_t variables. rem = lhs -rhs: */ |
46 | #define ktime_sub(lhs, rhs) ((lhs) - (rhs)) |
47 | |
48 | /* Add two ktime_t variables. res = lhs + rhs: */ |
49 | #define ktime_add(lhs, rhs) ((lhs) + (rhs)) |
50 | |
51 | /* |
52 | * Same as ktime_add(), but avoids undefined behaviour on overflow; however, |
53 | * this means that you must check the result for overflow yourself. |
54 | */ |
55 | #define ktime_add_unsafe(lhs, rhs) ((u64) (lhs) + (rhs)) |
56 | |
57 | /* |
58 | * Add a ktime_t variable and a scalar nanosecond value. |
59 | * res = kt + nsval: |
60 | */ |
61 | #define ktime_add_ns(kt, nsval) ((kt) + (nsval)) |
62 | |
63 | /* |
64 | * Subtract a scalar nanosecod from a ktime_t variable |
65 | * res = kt - nsval: |
66 | */ |
67 | #define ktime_sub_ns(kt, nsval) ((kt) - (nsval)) |
68 | |
69 | /* convert a timespec to ktime_t format: */ |
70 | static inline ktime_t timespec_to_ktime(struct timespec ts) |
71 | { |
72 | return ktime_set(ts.tv_sec, ts.tv_nsec); |
73 | } |
74 | |
75 | /* convert a timespec64 to ktime_t format: */ |
76 | static inline ktime_t timespec64_to_ktime(struct timespec64 ts) |
77 | { |
78 | return ktime_set(ts.tv_sec, ts.tv_nsec); |
79 | } |
80 | |
81 | /* convert a timeval to ktime_t format: */ |
82 | static inline ktime_t timeval_to_ktime(struct timeval tv) |
83 | { |
84 | return ktime_set(tv.tv_sec, tv.tv_usec * NSEC_PER_USEC); |
85 | } |
86 | |
87 | /* Map the ktime_t to timespec conversion to ns_to_timespec function */ |
88 | #define ktime_to_timespec(kt) ns_to_timespec((kt)) |
89 | |
90 | /* Map the ktime_t to timespec conversion to ns_to_timespec function */ |
91 | #define ktime_to_timespec64(kt) ns_to_timespec64((kt)) |
92 | |
93 | /* Map the ktime_t to timeval conversion to ns_to_timeval function */ |
94 | #define ktime_to_timeval(kt) ns_to_timeval((kt)) |
95 | |
96 | /* Convert ktime_t to nanoseconds */ |
97 | static inline s64 ktime_to_ns(const ktime_t kt) |
98 | { |
99 | return kt; |
100 | } |
101 | |
102 | /** |
103 | * ktime_compare - Compares two ktime_t variables for less, greater or equal |
104 | * @cmp1: comparable1 |
105 | * @cmp2: comparable2 |
106 | * |
107 | * Return: ... |
108 | * cmp1 < cmp2: return <0 |
109 | * cmp1 == cmp2: return 0 |
110 | * cmp1 > cmp2: return >0 |
111 | */ |
112 | static inline int ktime_compare(const ktime_t cmp1, const ktime_t cmp2) |
113 | { |
114 | if (cmp1 < cmp2) |
115 | return -1; |
116 | if (cmp1 > cmp2) |
117 | return 1; |
118 | return 0; |
119 | } |
120 | |
121 | /** |
122 | * ktime_after - Compare if a ktime_t value is bigger than another one. |
123 | * @cmp1: comparable1 |
124 | * @cmp2: comparable2 |
125 | * |
126 | * Return: true if cmp1 happened after cmp2. |
127 | */ |
128 | static inline bool ktime_after(const ktime_t cmp1, const ktime_t cmp2) |
129 | { |
130 | return ktime_compare(cmp1, cmp2) > 0; |
131 | } |
132 | |
133 | /** |
134 | * ktime_before - Compare if a ktime_t value is smaller than another one. |
135 | * @cmp1: comparable1 |
136 | * @cmp2: comparable2 |
137 | * |
138 | * Return: true if cmp1 happened before cmp2. |
139 | */ |
140 | static inline bool ktime_before(const ktime_t cmp1, const ktime_t cmp2) |
141 | { |
142 | return ktime_compare(cmp1, cmp2) < 0; |
143 | } |
144 | |
145 | #if BITS_PER_LONG < 64 |
146 | extern s64 __ktime_divns(const ktime_t kt, s64 div); |
147 | static inline s64 ktime_divns(const ktime_t kt, s64 div) |
148 | { |
149 | /* |
150 | * Negative divisors could cause an inf loop, |
151 | * so bug out here. |
152 | */ |
153 | BUG_ON(div < 0); |
154 | if (__builtin_constant_p(div) && !(div >> 32)) { |
155 | s64 ns = kt; |
156 | u64 tmp = ns < 0 ? -ns : ns; |
157 | |
158 | do_div(tmp, div); |
159 | return ns < 0 ? -tmp : tmp; |
160 | } else { |
161 | return __ktime_divns(kt, div); |
162 | } |
163 | } |
164 | #else /* BITS_PER_LONG < 64 */ |
165 | static inline s64 ktime_divns(const ktime_t kt, s64 div) |
166 | { |
167 | /* |
168 | * 32-bit implementation cannot handle negative divisors, |
169 | * so catch them on 64bit as well. |
170 | */ |
171 | WARN_ON(div < 0); |
172 | return kt / div; |
173 | } |
174 | #endif |
175 | |
176 | static inline s64 ktime_to_us(const ktime_t kt) |
177 | { |
178 | return ktime_divns(kt, NSEC_PER_USEC); |
179 | } |
180 | |
181 | static inline s64 ktime_to_ms(const ktime_t kt) |
182 | { |
183 | return ktime_divns(kt, NSEC_PER_MSEC); |
184 | } |
185 | |
186 | static inline s64 ktime_us_delta(const ktime_t later, const ktime_t earlier) |
187 | { |
188 | return ktime_to_us(ktime_sub(later, earlier)); |
189 | } |
190 | |
191 | static inline s64 ktime_ms_delta(const ktime_t later, const ktime_t earlier) |
192 | { |
193 | return ktime_to_ms(ktime_sub(later, earlier)); |
194 | } |
195 | |
196 | static inline ktime_t ktime_add_us(const ktime_t kt, const u64 usec) |
197 | { |
198 | return ktime_add_ns(kt, usec * NSEC_PER_USEC); |
199 | } |
200 | |
201 | static inline ktime_t ktime_add_ms(const ktime_t kt, const u64 msec) |
202 | { |
203 | return ktime_add_ns(kt, msec * NSEC_PER_MSEC); |
204 | } |
205 | |
206 | static inline ktime_t ktime_sub_us(const ktime_t kt, const u64 usec) |
207 | { |
208 | return ktime_sub_ns(kt, usec * NSEC_PER_USEC); |
209 | } |
210 | |
211 | static inline ktime_t ktime_sub_ms(const ktime_t kt, const u64 msec) |
212 | { |
213 | return ktime_sub_ns(kt, msec * NSEC_PER_MSEC); |
214 | } |
215 | |
216 | extern ktime_t ktime_add_safe(const ktime_t lhs, const ktime_t rhs); |
217 | |
218 | /** |
219 | * ktime_to_timespec_cond - convert a ktime_t variable to timespec |
220 | * format only if the variable contains data |
221 | * @kt: the ktime_t variable to convert |
222 | * @ts: the timespec variable to store the result in |
223 | * |
224 | * Return: %true if there was a successful conversion, %false if kt was 0. |
225 | */ |
226 | static inline __must_check bool ktime_to_timespec_cond(const ktime_t kt, |
227 | struct timespec *ts) |
228 | { |
229 | if (kt) { |
230 | *ts = ktime_to_timespec(kt); |
231 | return true; |
232 | } else { |
233 | return false; |
234 | } |
235 | } |
236 | |
237 | /** |
238 | * ktime_to_timespec64_cond - convert a ktime_t variable to timespec64 |
239 | * format only if the variable contains data |
240 | * @kt: the ktime_t variable to convert |
241 | * @ts: the timespec variable to store the result in |
242 | * |
243 | * Return: %true if there was a successful conversion, %false if kt was 0. |
244 | */ |
245 | static inline __must_check bool ktime_to_timespec64_cond(const ktime_t kt, |
246 | struct timespec64 *ts) |
247 | { |
248 | if (kt) { |
249 | *ts = ktime_to_timespec64(kt); |
250 | return true; |
251 | } else { |
252 | return false; |
253 | } |
254 | } |
255 | |
256 | /* |
257 | * The resolution of the clocks. The resolution value is returned in |
258 | * the clock_getres() system call to give application programmers an |
259 | * idea of the (in)accuracy of timers. Timer values are rounded up to |
260 | * this resolution values. |
261 | */ |
262 | #define LOW_RES_NSEC TICK_NSEC |
263 | #define KTIME_LOW_RES (LOW_RES_NSEC) |
264 | |
265 | static inline ktime_t ns_to_ktime(u64 ns) |
266 | { |
267 | return ns; |
268 | } |
269 | |
270 | static inline ktime_t ms_to_ktime(u64 ms) |
271 | { |
272 | return ms * NSEC_PER_MSEC; |
273 | } |
274 | |
275 | # include <linux/timekeeping.h> |
276 | # include <linux/timekeeping32.h> |
277 | |
278 | #endif |
279 | |