1 /* This file is part of the Linux Trace Toolkit trace reading library
2 * Copyright (C) 2003-2004 Michel Dagenais
4 * This library is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU Lesser General Public
6 * License Version 2.1 as published by the Free Software Foundation.
8 * This library is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11 * Lesser General Public License for more details.
13 * You should have received a copy of the GNU Lesser General Public
14 * License along with this library; if not, write to the
15 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
16 * Boston, MA 02111-1307, USA.
23 #include <ltt/compiler.h>
25 typedef struct _LttTime
{
27 unsigned long tv_nsec
;
31 #define NANOSECONDS_PER_SECOND 1000000000
32 #define SHIFT_CONST 1.07374182400631629848
34 static const LttTime ltt_time_zero
= { 0, 0 };
36 static const LttTime ltt_time_one
= { 0, 1 };
38 static const LttTime ltt_time_infinite
= { G_MAXUINT
, NANOSECONDS_PER_SECOND
};
40 static inline LttTime
ltt_time_sub(LttTime t1
, LttTime t2
)
43 res
.tv_sec
= t1
.tv_sec
- t2
.tv_sec
;
44 res
.tv_nsec
= t1
.tv_nsec
- t2
.tv_nsec
;
45 /* unlikely : given equal chance to be anywhere in t1.tv_nsec, and
46 * higher probability of low value for t2.tv_sec, we will habitually
49 if(unlikely(t1
.tv_nsec
< t2
.tv_nsec
)) {
51 res
.tv_nsec
+= NANOSECONDS_PER_SECOND
;
57 static inline LttTime
ltt_time_add(LttTime t1
, LttTime t2
)
60 res
.tv_nsec
= t1
.tv_nsec
+ t2
.tv_nsec
;
61 res
.tv_sec
= t1
.tv_sec
+ t2
.tv_sec
;
62 /* unlikely : given equal chance to be anywhere in t1.tv_nsec, and
63 * higher probability of low value for t2.tv_sec, we will habitually
66 if(unlikely(res
.tv_nsec
>= NANOSECONDS_PER_SECOND
)) {
68 res
.tv_nsec
-= NANOSECONDS_PER_SECOND
;
73 /* Fastest comparison : t1 > t2 */
74 static inline int ltt_time_compare(LttTime t1
, LttTime t2
)
77 if(likely(t1
.tv_sec
> t2
.tv_sec
)) ret
= 1;
78 else if(unlikely(t1
.tv_sec
< t2
.tv_sec
)) ret
= -1;
79 else if(likely(t1
.tv_nsec
> t2
.tv_nsec
)) ret
= 1;
80 else if(unlikely(t1
.tv_nsec
< t2
.tv_nsec
)) ret
= -1;
85 #define LTT_TIME_MIN(a,b) ((ltt_time_compare((a),(b)) < 0) ? (a) : (b))
86 #define LTT_TIME_MAX(a,b) ((ltt_time_compare((a),(b)) > 0) ? (a) : (b))
88 #define MAX_TV_SEC_TO_DOUBLE 0x7FFFFF
89 static inline double ltt_time_to_double(LttTime t1
)
91 /* We lose precision if tv_sec is > than (2^23)-1
93 * Max values that fits in a double (53 bits precision on normalised
95 * tv_nsec : NANOSECONDS_PER_SECONDS : 2^30
97 * So we have 53-30 = 23 bits left for tv_sec.
100 g_assert(t1
.tv_sec
<= MAX_TV_SEC_TO_DOUBLE
);
101 if(t1
.tv_sec
> MAX_TV_SEC_TO_DOUBLE
)
102 g_warning("Precision loss in conversion LttTime to double");
104 return ((double)t1
.tv_sec
* (double)NANOSECONDS_PER_SECOND
) + (double)t1
.tv_nsec
;
108 static inline LttTime
ltt_time_from_double(double t1
)
110 /* We lose precision if tv_sec is > than (2^23)-1
112 * Max values that fits in a double (53 bits precision on normalised
114 * tv_nsec : NANOSECONDS_PER_SECONDS : 2^30
116 * So we have 53-30 = 23 bits left for tv_sec.
119 g_assert(t1
<= MAX_TV_SEC_TO_DOUBLE
);
120 if(t1
> MAX_TV_SEC_TO_DOUBLE
)
121 g_warning("Conversion from non precise double to LttTime");
124 //res.tv_sec = t1/(double)NANOSECONDS_PER_SECOND;
125 res
.tv_sec
= (guint64
)(t1
* SHIFT_CONST
) >> 30;
126 res
.tv_nsec
= (t1
- (res
.tv_sec
*NANOSECONDS_PER_SECOND
));
130 /* Use ltt_time_to_double and ltt_time_from_double to check for lack
133 static inline LttTime
ltt_time_mul(LttTime t1
, double d
)
137 double time_double
= ltt_time_to_double(t1
);
139 time_double
= time_double
* d
;
141 res
= ltt_time_from_double(time_double
);
146 /* What is that ? (Mathieu) */
153 sec
= t1
.tv_sec
/ (double)d
;
155 res
.tv_nsec
= t1
.tv_nsec
/ (double)d
+ (sec
- res
.tv_sec
) *
156 NANOSECONDS_PER_SECOND
;
157 res
.tv_sec
+= res
.tv_nsec
/ NANOSECONDS_PER_SECOND
;
158 res
.tv_nsec
%= NANOSECONDS_PER_SECOND
;
165 /* Use ltt_time_to_double and ltt_time_from_double to check for lack
168 static inline LttTime
ltt_time_div(LttTime t1
, double d
)
172 double time_double
= ltt_time_to_double(t1
);
174 time_double
= time_double
/ d
;
176 res
= ltt_time_from_double(time_double
);
185 sec
= t1
.tv_sec
/ (double)f
;
187 res
.tv_nsec
= t1
.tv_nsec
/ (double)f
+ (sec
- res
.tv_sec
) *
188 NANOSECONDS_PER_SECOND
;
189 res
.tv_sec
+= res
.tv_nsec
/ NANOSECONDS_PER_SECOND
;
190 res
.tv_nsec
%= NANOSECONDS_PER_SECOND
;
195 static inline guint64
ltt_time_to_uint64(LttTime t1
)
197 return (guint64
)t1
.tv_sec
*NANOSECONDS_PER_SECOND
198 + (guint64
)t1
.tv_nsec
;
202 #define MAX_TV_SEC_TO_UINT64 0x3FFFFFFFFFFFFFFFULL
203 static inline LttTime
ltt_time_from_uint64(guint64 t1
)
205 /* We lose precision if tv_sec is > than (2^62)-1
208 g_assert(t1
<= MAX_TV_SEC_TO_UINT64
);
209 if(t1
> MAX_TV_SEC_TO_UINT64
)
210 g_warning("Conversion from non precise uint64 to LttTime");
213 res
.tv_sec
= t1
/NANOSECONDS_PER_SECOND
;
214 res
.tv_nsec
= (t1
- res
.tv_sec
*NANOSECONDS_PER_SECOND
);