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 /* 2^30/1.07374182400631629848 = 1000000000.0 */
33 #define DOUBLE_SHIFT_CONST 1.07374182400631629848
34 #define DOUBLE_SHIFT 30
36 /* 1953125 * 2^9 = NANOSECONDS_PER_SECOND */
37 #define LTT_TIME_UINT_SHIFT_CONST 1953125
38 #define LTT_TIME_UINT_SHIFT 9
41 static const LttTime ltt_time_zero
= { 0, 0 };
43 static const LttTime ltt_time_one
= { 0, 1 };
45 static const LttTime ltt_time_infinite
= { G_MAXUINT
, NANOSECONDS_PER_SECOND
};
47 static inline LttTime
ltt_time_sub(LttTime t1
, LttTime t2
)
50 res
.tv_sec
= t1
.tv_sec
- t2
.tv_sec
;
51 res
.tv_nsec
= t1
.tv_nsec
- t2
.tv_nsec
;
52 /* unlikely : given equal chance to be anywhere in t1.tv_nsec, and
53 * higher probability of low value for t2.tv_sec, we will habitually
56 if(unlikely(t1
.tv_nsec
< t2
.tv_nsec
)) {
58 res
.tv_nsec
+= NANOSECONDS_PER_SECOND
;
64 static inline LttTime
ltt_time_add(LttTime t1
, LttTime t2
)
67 res
.tv_nsec
= t1
.tv_nsec
+ t2
.tv_nsec
;
68 res
.tv_sec
= t1
.tv_sec
+ t2
.tv_sec
;
69 /* unlikely : given equal chance to be anywhere in t1.tv_nsec, and
70 * higher probability of low value for t2.tv_sec, we will habitually
73 if(unlikely(res
.tv_nsec
>= NANOSECONDS_PER_SECOND
)) {
75 res
.tv_nsec
-= NANOSECONDS_PER_SECOND
;
80 /* Fastest comparison : t1 > t2 */
81 static inline int ltt_time_compare(LttTime t1
, LttTime t2
)
84 if(likely(t1
.tv_sec
> t2
.tv_sec
)) ret
= 1;
85 else if(unlikely(t1
.tv_sec
< t2
.tv_sec
)) ret
= -1;
86 else if(likely(t1
.tv_nsec
> t2
.tv_nsec
)) ret
= 1;
87 else if(unlikely(t1
.tv_nsec
< t2
.tv_nsec
)) ret
= -1;
92 #define LTT_TIME_MIN(a,b) ((ltt_time_compare((a),(b)) < 0) ? (a) : (b))
93 #define LTT_TIME_MAX(a,b) ((ltt_time_compare((a),(b)) > 0) ? (a) : (b))
95 #define MAX_TV_SEC_TO_DOUBLE 0x7FFFFF
96 static inline double ltt_time_to_double(LttTime t1
)
98 /* We lose precision if tv_sec is > than (2^23)-1
100 * Max values that fits in a double (53 bits precision on normalised
102 * tv_nsec : NANOSECONDS_PER_SECONDS : 2^30
104 * So we have 53-30 = 23 bits left for tv_sec.
107 g_assert(t1
.tv_sec
<= MAX_TV_SEC_TO_DOUBLE
);
108 if(t1
.tv_sec
> MAX_TV_SEC_TO_DOUBLE
)
109 g_warning("Precision loss in conversion LttTime to double");
111 return ((double)((guint64
)t1
.tv_sec
<<DOUBLE_SHIFT
)
112 / (double)DOUBLE_SHIFT_CONST
)
113 + (double)t1
.tv_nsec
;
117 static inline LttTime
ltt_time_from_double(double t1
)
119 /* We lose precision if tv_sec is > than (2^23)-1
121 * Max values that fits in a double (53 bits precision on normalised
123 * tv_nsec : NANOSECONDS_PER_SECONDS : 2^30
125 * So we have 53-30 = 23 bits left for tv_sec.
128 g_assert(t1
<= MAX_TV_SEC_TO_DOUBLE
);
129 if(t1
> MAX_TV_SEC_TO_DOUBLE
)
130 g_warning("Conversion from non precise double to LttTime");
133 //res.tv_sec = t1/(double)NANOSECONDS_PER_SECOND;
134 res
.tv_sec
= (guint64
)(t1
* DOUBLE_SHIFT_CONST
) >> DOUBLE_SHIFT
;
135 res
.tv_nsec
= (t1
- (((guint64
)res
.tv_sec
<<LTT_TIME_UINT_SHIFT
))
136 * LTT_TIME_UINT_SHIFT_CONST
);
140 /* Use ltt_time_to_double and ltt_time_from_double to check for lack
143 static inline LttTime
ltt_time_mul(LttTime t1
, double d
)
147 double time_double
= ltt_time_to_double(t1
);
149 time_double
= time_double
* d
;
151 res
= ltt_time_from_double(time_double
);
156 /* What is that ? (Mathieu) */
163 sec
= t1
.tv_sec
/ (double)d
;
165 res
.tv_nsec
= t1
.tv_nsec
/ (double)d
+ (sec
- res
.tv_sec
) *
166 NANOSECONDS_PER_SECOND
;
167 res
.tv_sec
+= res
.tv_nsec
/ NANOSECONDS_PER_SECOND
;
168 res
.tv_nsec
%= NANOSECONDS_PER_SECOND
;
175 /* Use ltt_time_to_double and ltt_time_from_double to check for lack
178 static inline LttTime
ltt_time_div(LttTime t1
, double d
)
182 double time_double
= ltt_time_to_double(t1
);
184 time_double
= time_double
/ d
;
186 res
= ltt_time_from_double(time_double
);
195 sec
= t1
.tv_sec
/ (double)f
;
197 res
.tv_nsec
= t1
.tv_nsec
/ (double)f
+ (sec
- res
.tv_sec
) *
198 NANOSECONDS_PER_SECOND
;
199 res
.tv_sec
+= res
.tv_nsec
/ NANOSECONDS_PER_SECOND
;
200 res
.tv_nsec
%= NANOSECONDS_PER_SECOND
;
206 static inline guint64
ltt_time_to_uint64(LttTime t1
)
208 return (guint64
)(t1
.tv_sec
*LTT_TIME_UINT_SHIFT_CONST
) >> LTT_TIME_UINT_SHIFT
209 + (guint64
)t1
.tv_nsec
;
213 #define MAX_TV_SEC_TO_UINT64 0x3FFFFFFFFFFFFFFFULL
215 /* The likely branch is with sec != 0, because most events in a bloc
216 * will be over 1s from the block start. (see tracefile.c)
218 static inline LttTime
ltt_time_from_uint64(guint64 t1
)
220 /* We lose precision if tv_sec is > than (2^62)-1
223 g_assert(t1
<= MAX_TV_SEC_TO_UINT64
);
224 if(t1
> MAX_TV_SEC_TO_UINT64
)
225 g_warning("Conversion from uint64 to non precise LttTime");
228 //if(unlikely(t1 >= NANOSECONDS_PER_SECOND)) {
229 if(likely(t1
>>LTT_TIME_UINT_SHIFT
>= LTT_TIME_UINT_SHIFT_CONST
)) {
230 //res.tv_sec = t1/NANOSECONDS_PER_SECOND;
231 res
.tv_sec
= (t1
>>LTT_TIME_UINT_SHIFT
)
232 /LTT_TIME_UINT_SHIFT_CONST
; // acceleration
233 res
.tv_nsec
= (t1
- res
.tv_sec
*NANOSECONDS_PER_SECOND
);
236 res
.tv_nsec
= (guint32
)t1
;