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 | #include <asm/bug.h> |
27 | |
28 | /* Nanosecond scalar representation for kernel time values */ |
29 | typedef s64 ktime_t; |
30 | |
31 | /** |
32 | * ktime_set - Set a ktime_t variable from a seconds/nanoseconds value |
33 | * @secs: seconds to set |
34 | * @nsecs: nanoseconds to set |
35 | * |
36 | * Return: The ktime_t representation of the value. |
37 | */ |
38 | static inline ktime_t ktime_set(const s64 secs, const unsigned long nsecs) |
39 | { |
40 | if (unlikely(secs >= KTIME_SEC_MAX)) |
41 | return KTIME_MAX; |
42 | |
43 | return secs * NSEC_PER_SEC + (s64)nsecs; |
44 | } |
45 | |
46 | /* Subtract two ktime_t variables. rem = lhs -rhs: */ |
47 | #define ktime_sub(lhs, rhs) ((lhs) - (rhs)) |
48 | |
49 | /* Add two ktime_t variables. res = lhs + rhs: */ |
50 | #define ktime_add(lhs, rhs) ((lhs) + (rhs)) |
51 | |
52 | /* |
53 | * Same as ktime_add(), but avoids undefined behaviour on overflow; however, |
54 | * this means that you must check the result for overflow yourself. |
55 | */ |
56 | #define ktime_add_unsafe(lhs, rhs) ((u64) (lhs) + (rhs)) |
57 | |
58 | /* |
59 | * Add a ktime_t variable and a scalar nanosecond value. |
60 | * res = kt + nsval: |
61 | */ |
62 | #define ktime_add_ns(kt, nsval) ((kt) + (nsval)) |
63 | |
64 | /* |
65 | * Subtract a scalar nanosecod from a ktime_t variable |
66 | * res = kt - nsval: |
67 | */ |
68 | #define ktime_sub_ns(kt, nsval) ((kt) - (nsval)) |
69 | |
70 | /* convert a timespec64 to ktime_t format: */ |
71 | static inline ktime_t timespec64_to_ktime(struct timespec64 ts) |
72 | { |
73 | return ktime_set(secs: ts.tv_sec, nsecs: ts.tv_nsec); |
74 | } |
75 | |
76 | /* Map the ktime_t to timespec conversion to ns_to_timespec function */ |
77 | #define ktime_to_timespec64(kt) ns_to_timespec64((kt)) |
78 | |
79 | /* Convert ktime_t to nanoseconds */ |
80 | static inline s64 ktime_to_ns(const ktime_t kt) |
81 | { |
82 | return kt; |
83 | } |
84 | |
85 | /** |
86 | * ktime_compare - Compares two ktime_t variables for less, greater or equal |
87 | * @cmp1: comparable1 |
88 | * @cmp2: comparable2 |
89 | * |
90 | * Return: ... |
91 | * cmp1 < cmp2: return <0 |
92 | * cmp1 == cmp2: return 0 |
93 | * cmp1 > cmp2: return >0 |
94 | */ |
95 | static inline int ktime_compare(const ktime_t cmp1, const ktime_t cmp2) |
96 | { |
97 | if (cmp1 < cmp2) |
98 | return -1; |
99 | if (cmp1 > cmp2) |
100 | return 1; |
101 | return 0; |
102 | } |
103 | |
104 | /** |
105 | * ktime_after - Compare if a ktime_t value is bigger than another one. |
106 | * @cmp1: comparable1 |
107 | * @cmp2: comparable2 |
108 | * |
109 | * Return: true if cmp1 happened after cmp2. |
110 | */ |
111 | static inline bool ktime_after(const ktime_t cmp1, const ktime_t cmp2) |
112 | { |
113 | return ktime_compare(cmp1, cmp2) > 0; |
114 | } |
115 | |
116 | /** |
117 | * ktime_before - Compare if a ktime_t value is smaller than another one. |
118 | * @cmp1: comparable1 |
119 | * @cmp2: comparable2 |
120 | * |
121 | * Return: true if cmp1 happened before cmp2. |
122 | */ |
123 | static inline bool ktime_before(const ktime_t cmp1, const ktime_t cmp2) |
124 | { |
125 | return ktime_compare(cmp1, cmp2) < 0; |
126 | } |
127 | |
128 | #if BITS_PER_LONG < 64 |
129 | extern s64 __ktime_divns(const ktime_t kt, s64 div); |
130 | static inline s64 ktime_divns(const ktime_t kt, s64 div) |
131 | { |
132 | /* |
133 | * Negative divisors could cause an inf loop, |
134 | * so bug out here. |
135 | */ |
136 | BUG_ON(div < 0); |
137 | if (__builtin_constant_p(div) && !(div >> 32)) { |
138 | s64 ns = kt; |
139 | u64 tmp = ns < 0 ? -ns : ns; |
140 | |
141 | do_div(tmp, div); |
142 | return ns < 0 ? -tmp : tmp; |
143 | } else { |
144 | return __ktime_divns(kt, div); |
145 | } |
146 | } |
147 | #else /* BITS_PER_LONG < 64 */ |
148 | static inline s64 ktime_divns(const ktime_t kt, s64 div) |
149 | { |
150 | /* |
151 | * 32-bit implementation cannot handle negative divisors, |
152 | * so catch them on 64bit as well. |
153 | */ |
154 | WARN_ON(div < 0); |
155 | return kt / div; |
156 | } |
157 | #endif |
158 | |
159 | static inline s64 ktime_to_us(const ktime_t kt) |
160 | { |
161 | return ktime_divns(kt, NSEC_PER_USEC); |
162 | } |
163 | |
164 | static inline s64 ktime_to_ms(const ktime_t kt) |
165 | { |
166 | return ktime_divns(kt, NSEC_PER_MSEC); |
167 | } |
168 | |
169 | static inline s64 ktime_us_delta(const ktime_t later, const ktime_t earlier) |
170 | { |
171 | return ktime_to_us(ktime_sub(later, earlier)); |
172 | } |
173 | |
174 | static inline s64 ktime_ms_delta(const ktime_t later, const ktime_t earlier) |
175 | { |
176 | return ktime_to_ms(ktime_sub(later, earlier)); |
177 | } |
178 | |
179 | static inline ktime_t ktime_add_us(const ktime_t kt, const u64 usec) |
180 | { |
181 | return ktime_add_ns(kt, usec * NSEC_PER_USEC); |
182 | } |
183 | |
184 | static inline ktime_t ktime_add_ms(const ktime_t kt, const u64 msec) |
185 | { |
186 | return ktime_add_ns(kt, msec * NSEC_PER_MSEC); |
187 | } |
188 | |
189 | static inline ktime_t ktime_sub_us(const ktime_t kt, const u64 usec) |
190 | { |
191 | return ktime_sub_ns(kt, usec * NSEC_PER_USEC); |
192 | } |
193 | |
194 | static inline ktime_t ktime_sub_ms(const ktime_t kt, const u64 msec) |
195 | { |
196 | return ktime_sub_ns(kt, msec * NSEC_PER_MSEC); |
197 | } |
198 | |
199 | extern ktime_t ktime_add_safe(const ktime_t lhs, const ktime_t rhs); |
200 | |
201 | /** |
202 | * ktime_to_timespec64_cond - convert a ktime_t variable to timespec64 |
203 | * format only if the variable contains data |
204 | * @kt: the ktime_t variable to convert |
205 | * @ts: the timespec variable to store the result in |
206 | * |
207 | * Return: %true if there was a successful conversion, %false if kt was 0. |
208 | */ |
209 | static inline __must_check bool ktime_to_timespec64_cond(const ktime_t kt, |
210 | struct timespec64 *ts) |
211 | { |
212 | if (kt) { |
213 | *ts = ktime_to_timespec64(kt); |
214 | return true; |
215 | } else { |
216 | return false; |
217 | } |
218 | } |
219 | |
220 | #include <vdso/ktime.h> |
221 | |
222 | static inline ktime_t ns_to_ktime(u64 ns) |
223 | { |
224 | return ns; |
225 | } |
226 | |
227 | static inline ktime_t ms_to_ktime(u64 ms) |
228 | { |
229 | return ms * NSEC_PER_MSEC; |
230 | } |
231 | |
232 | # include <linux/timekeeping.h> |
233 | |
234 | #endif |
235 | |