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 <asm/bug.h> |
25 | #include <linux/jiffies.h> |
26 | #include <linux/time.h> |
27 | #include <linux/types.h> |
28 | |
29 | /** |
30 | * ktime_set - Set a ktime_t variable from a seconds/nanoseconds value |
31 | * @secs: seconds to set |
32 | * @nsecs: nanoseconds to set |
33 | * |
34 | * Return: The ktime_t representation of the value. |
35 | */ |
36 | static inline ktime_t ktime_set(const s64 secs, const unsigned long nsecs) |
37 | { |
38 | if (unlikely(secs >= KTIME_SEC_MAX)) |
39 | return KTIME_MAX; |
40 | |
41 | return secs * NSEC_PER_SEC + (s64)nsecs; |
42 | } |
43 | |
44 | /* Subtract two ktime_t variables. rem = lhs -rhs: */ |
45 | #define ktime_sub(lhs, rhs) ((lhs) - (rhs)) |
46 | |
47 | /* Add two ktime_t variables. res = lhs + rhs: */ |
48 | #define ktime_add(lhs, rhs) ((lhs) + (rhs)) |
49 | |
50 | /* |
51 | * Same as ktime_add(), but avoids undefined behaviour on overflow; however, |
52 | * this means that you must check the result for overflow yourself. |
53 | */ |
54 | #define ktime_add_unsafe(lhs, rhs) ((u64) (lhs) + (rhs)) |
55 | |
56 | /* |
57 | * Add a ktime_t variable and a scalar nanosecond value. |
58 | * res = kt + nsval: |
59 | */ |
60 | #define ktime_add_ns(kt, nsval) ((kt) + (nsval)) |
61 | |
62 | /* |
63 | * Subtract a scalar nanosecod from a ktime_t variable |
64 | * res = kt - nsval: |
65 | */ |
66 | #define ktime_sub_ns(kt, nsval) ((kt) - (nsval)) |
67 | |
68 | /* convert a timespec64 to ktime_t format: */ |
69 | static inline ktime_t timespec64_to_ktime(struct timespec64 ts) |
70 | { |
71 | return ktime_set(secs: ts.tv_sec, nsecs: ts.tv_nsec); |
72 | } |
73 | |
74 | /* Map the ktime_t to timespec conversion to ns_to_timespec function */ |
75 | #define ktime_to_timespec64(kt) ns_to_timespec64((kt)) |
76 | |
77 | /* Convert ktime_t to nanoseconds */ |
78 | static inline s64 ktime_to_ns(const ktime_t kt) |
79 | { |
80 | return kt; |
81 | } |
82 | |
83 | /** |
84 | * ktime_compare - Compares two ktime_t variables for less, greater or equal |
85 | * @cmp1: comparable1 |
86 | * @cmp2: comparable2 |
87 | * |
88 | * Return: ... |
89 | * cmp1 < cmp2: return <0 |
90 | * cmp1 == cmp2: return 0 |
91 | * cmp1 > cmp2: return >0 |
92 | */ |
93 | static inline int ktime_compare(const ktime_t cmp1, const ktime_t cmp2) |
94 | { |
95 | if (cmp1 < cmp2) |
96 | return -1; |
97 | if (cmp1 > cmp2) |
98 | return 1; |
99 | return 0; |
100 | } |
101 | |
102 | /** |
103 | * ktime_after - Compare if a ktime_t value is bigger than another one. |
104 | * @cmp1: comparable1 |
105 | * @cmp2: comparable2 |
106 | * |
107 | * Return: true if cmp1 happened after cmp2. |
108 | */ |
109 | static inline bool ktime_after(const ktime_t cmp1, const ktime_t cmp2) |
110 | { |
111 | return ktime_compare(cmp1, cmp2) > 0; |
112 | } |
113 | |
114 | /** |
115 | * ktime_before - Compare if a ktime_t value is smaller than another one. |
116 | * @cmp1: comparable1 |
117 | * @cmp2: comparable2 |
118 | * |
119 | * Return: true if cmp1 happened before cmp2. |
120 | */ |
121 | static inline bool ktime_before(const ktime_t cmp1, const ktime_t cmp2) |
122 | { |
123 | return ktime_compare(cmp1, cmp2) < 0; |
124 | } |
125 | |
126 | #if BITS_PER_LONG < 64 |
127 | extern s64 __ktime_divns(const ktime_t kt, s64 div); |
128 | static inline s64 ktime_divns(const ktime_t kt, s64 div) |
129 | { |
130 | /* |
131 | * Negative divisors could cause an inf loop, |
132 | * so bug out here. |
133 | */ |
134 | BUG_ON(div < 0); |
135 | if (__builtin_constant_p(div) && !(div >> 32)) { |
136 | s64 ns = kt; |
137 | u64 tmp = ns < 0 ? -ns : ns; |
138 | |
139 | do_div(tmp, div); |
140 | return ns < 0 ? -tmp : tmp; |
141 | } else { |
142 | return __ktime_divns(kt, div); |
143 | } |
144 | } |
145 | #else /* BITS_PER_LONG < 64 */ |
146 | static inline s64 ktime_divns(const ktime_t kt, s64 div) |
147 | { |
148 | /* |
149 | * 32-bit implementation cannot handle negative divisors, |
150 | * so catch them on 64bit as well. |
151 | */ |
152 | WARN_ON(div < 0); |
153 | return kt / div; |
154 | } |
155 | #endif |
156 | |
157 | static inline s64 ktime_to_us(const ktime_t kt) |
158 | { |
159 | return ktime_divns(kt, NSEC_PER_USEC); |
160 | } |
161 | |
162 | static inline s64 ktime_to_ms(const ktime_t kt) |
163 | { |
164 | return ktime_divns(kt, NSEC_PER_MSEC); |
165 | } |
166 | |
167 | static inline s64 ktime_us_delta(const ktime_t later, const ktime_t earlier) |
168 | { |
169 | return ktime_to_us(ktime_sub(later, earlier)); |
170 | } |
171 | |
172 | static inline s64 ktime_ms_delta(const ktime_t later, const ktime_t earlier) |
173 | { |
174 | return ktime_to_ms(ktime_sub(later, earlier)); |
175 | } |
176 | |
177 | static inline ktime_t ktime_add_us(const ktime_t kt, const u64 usec) |
178 | { |
179 | return ktime_add_ns(kt, usec * NSEC_PER_USEC); |
180 | } |
181 | |
182 | static inline ktime_t ktime_add_ms(const ktime_t kt, const u64 msec) |
183 | { |
184 | return ktime_add_ns(kt, msec * NSEC_PER_MSEC); |
185 | } |
186 | |
187 | static inline ktime_t ktime_sub_us(const ktime_t kt, const u64 usec) |
188 | { |
189 | return ktime_sub_ns(kt, usec * NSEC_PER_USEC); |
190 | } |
191 | |
192 | static inline ktime_t ktime_sub_ms(const ktime_t kt, const u64 msec) |
193 | { |
194 | return ktime_sub_ns(kt, msec * NSEC_PER_MSEC); |
195 | } |
196 | |
197 | extern ktime_t ktime_add_safe(const ktime_t lhs, const ktime_t rhs); |
198 | |
199 | /** |
200 | * ktime_to_timespec64_cond - convert a ktime_t variable to timespec64 |
201 | * format only if the variable contains data |
202 | * @kt: the ktime_t variable to convert |
203 | * @ts: the timespec variable to store the result in |
204 | * |
205 | * Return: %true if there was a successful conversion, %false if kt was 0. |
206 | */ |
207 | static inline __must_check bool ktime_to_timespec64_cond(const ktime_t kt, |
208 | struct timespec64 *ts) |
209 | { |
210 | if (kt) { |
211 | *ts = ktime_to_timespec64(kt); |
212 | return true; |
213 | } else { |
214 | return false; |
215 | } |
216 | } |
217 | |
218 | #include <vdso/ktime.h> |
219 | |
220 | static inline ktime_t ns_to_ktime(u64 ns) |
221 | { |
222 | return ns; |
223 | } |
224 | |
225 | static inline ktime_t ms_to_ktime(u64 ms) |
226 | { |
227 | return ms * NSEC_PER_MSEC; |
228 | } |
229 | |
230 | # include <linux/timekeeping.h> |
231 | |
232 | #endif |
233 | |