1 /* This file is part of the Linux Trace Toolkit trace reading library
2 * Copyright (C) 2003-2004 Michel Dagenais
3 * 2005 Mathieu Desnoyers
5 * This library is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU Lesser General Public
7 * License Version 2.1 as published by the Free Software Foundation.
9 * This library is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * Lesser General Public License for more details.
14 * You should have received a copy of the GNU Lesser General Public
15 * License along with this library; if not, write to the
16 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
17 * Boston, MA 02111-1307, USA.
25 #include <lttv/compiler.h>
27 typedef struct _LttTime
{
29 unsigned long tv_nsec
;
32 typedef struct _TimeInterval
{
37 #define NANOSECONDS_PER_SECOND 1000000000
39 /* We give the DIV and MUL constants so we can always multiply, for a
40 * division as well as a multiplication of NANOSECONDS_PER_SECOND */
41 /* 2^30/1.07374182400631629848 = 1000000000.0 */
42 #define DOUBLE_SHIFT_CONST_DIV 1.07374182400631629848
43 #define DOUBLE_SHIFT 30
45 /* 2^30*0.93132257461547851562 = 1000000000.0000000000 */
46 #define DOUBLE_SHIFT_CONST_MUL 0.93132257461547851562
49 /* 1953125 * 2^9 = NANOSECONDS_PER_SECOND */
50 #define LTT_TIME_UINT_SHIFT_CONST 1953125
51 #define LTT_TIME_UINT_SHIFT 9
54 static const LttTime ltt_time_zero
= { 0, 0 };
56 static const LttTime ltt_time_one
= { 0, 1 };
58 static const LttTime ltt_time_infinite
= { G_MAXUINT
, NANOSECONDS_PER_SECOND
};
60 static inline LttTime
ltt_time_sub(LttTime t1
, LttTime t2
)
63 res
.tv_sec
= t1
.tv_sec
- t2
.tv_sec
;
64 res
.tv_nsec
= t1
.tv_nsec
- t2
.tv_nsec
;
65 /* unlikely : given equal chance to be anywhere in t1.tv_nsec, and
66 * higher probability of low value for t2.tv_sec, we will habitually
69 if(unlikely(t1
.tv_nsec
< t2
.tv_nsec
)) {
71 res
.tv_nsec
+= NANOSECONDS_PER_SECOND
;
77 static inline LttTime
ltt_time_add(LttTime t1
, LttTime t2
)
80 res
.tv_nsec
= t1
.tv_nsec
+ t2
.tv_nsec
;
81 res
.tv_sec
= t1
.tv_sec
+ t2
.tv_sec
;
82 /* unlikely : given equal chance to be anywhere in t1.tv_nsec, and
83 * higher probability of low value for t2.tv_sec, we will habitually
86 if(unlikely(res
.tv_nsec
>= NANOSECONDS_PER_SECOND
)) {
88 res
.tv_nsec
-= NANOSECONDS_PER_SECOND
;
93 /* Fastest comparison : t1 > t2 */
94 static inline int ltt_time_compare(LttTime t1
, LttTime t2
)
97 if(likely(t1
.tv_sec
> t2
.tv_sec
)) ret
= 1;
98 else if(unlikely(t1
.tv_sec
< t2
.tv_sec
)) ret
= -1;
99 else if(likely(t1
.tv_nsec
> t2
.tv_nsec
)) ret
= 1;
100 else if(unlikely(t1
.tv_nsec
< t2
.tv_nsec
)) ret
= -1;
105 #define LTT_TIME_MIN(a,b) ((ltt_time_compare((a),(b)) < 0) ? (a) : (b))
106 #define LTT_TIME_MAX(a,b) ((ltt_time_compare((a),(b)) > 0) ? (a) : (b))
108 #define MAX_TV_SEC_TO_DOUBLE 0x7FFFFF
109 static inline double ltt_time_to_double(LttTime t1
)
111 /* We lose precision if tv_sec is > than (2^23)-1
113 * Max values that fits in a double (53 bits precision on normalised
115 * tv_nsec : NANOSECONDS_PER_SECONDS : 2^30
117 * So we have 53-30 = 23 bits left for tv_sec.
120 g_assert(t1
.tv_sec
<= MAX_TV_SEC_TO_DOUBLE
);
121 if(t1
.tv_sec
> MAX_TV_SEC_TO_DOUBLE
)
122 g_warning("Precision loss in conversion LttTime to double");
124 return ((double)((guint64
)t1
.tv_sec
<<DOUBLE_SHIFT
)
125 * (double)DOUBLE_SHIFT_CONST_MUL
)
126 + (double)t1
.tv_nsec
;
130 static inline LttTime
ltt_time_from_double(double t1
)
132 /* We lose precision if tv_sec is > than (2^23)-1
134 * Max values that fits in a double (53 bits precision on normalised
136 * tv_nsec : NANOSECONDS_PER_SECONDS : 2^30
138 * So we have 53-30 = 23 bits left for tv_sec.
141 g_assert(t1
<= MAX_TV_SEC_TO_DOUBLE
);
142 if(t1
> MAX_TV_SEC_TO_DOUBLE
)
143 g_warning("Conversion from non precise double to LttTime");
146 //res.tv_sec = t1/(double)NANOSECONDS_PER_SECOND;
147 res
.tv_sec
= (guint64
)(t1
* DOUBLE_SHIFT_CONST_DIV
) >> DOUBLE_SHIFT
;
148 res
.tv_nsec
= (t1
- (((guint64
)res
.tv_sec
<<LTT_TIME_UINT_SHIFT
))
149 * LTT_TIME_UINT_SHIFT_CONST
);
153 /* Use ltt_time_to_double and ltt_time_from_double to check for lack
156 static inline LttTime
ltt_time_mul(LttTime t1
, double d
)
160 double time_double
= ltt_time_to_double(t1
);
162 time_double
= time_double
* d
;
164 res
= ltt_time_from_double(time_double
);
169 /* What is that ? (Mathieu) */
176 sec
= t1
.tv_sec
/ (double)d
;
178 res
.tv_nsec
= t1
.tv_nsec
/ (double)d
+ (sec
- res
.tv_sec
) *
179 NANOSECONDS_PER_SECOND
;
180 res
.tv_sec
+= res
.tv_nsec
/ NANOSECONDS_PER_SECOND
;
181 res
.tv_nsec
%= NANOSECONDS_PER_SECOND
;
188 /* Use ltt_time_to_double and ltt_time_from_double to check for lack
191 static inline LttTime
ltt_time_div(LttTime t1
, double d
)
195 double time_double
= ltt_time_to_double(t1
);
197 time_double
= time_double
/ d
;
199 res
= ltt_time_from_double(time_double
);
208 sec
= t1
.tv_sec
/ (double)f
;
210 res
.tv_nsec
= t1
.tv_nsec
/ (double)f
+ (sec
- res
.tv_sec
) *
211 NANOSECONDS_PER_SECOND
;
212 res
.tv_sec
+= res
.tv_nsec
/ NANOSECONDS_PER_SECOND
;
213 res
.tv_nsec
%= NANOSECONDS_PER_SECOND
;
219 static inline guint64
ltt_time_to_uint64(LttTime t1
)
221 return (((guint64
)t1
.tv_sec
*LTT_TIME_UINT_SHIFT_CONST
) << LTT_TIME_UINT_SHIFT
)
222 + (guint64
)t1
.tv_nsec
;
226 #define MAX_TV_SEC_TO_UINT64 0x3FFFFFFFFFFFFFFFULL
228 /* The likely branch is with sec != 0, because most events in a bloc
229 * will be over 1s from the block start. (see tracefile.c)
231 static inline LttTime
ltt_time_from_uint64(guint64 t1
)
233 /* We lose precision if tv_sec is > than (2^62)-1
236 g_assert(t1
<= MAX_TV_SEC_TO_UINT64
);
237 if(t1
> MAX_TV_SEC_TO_UINT64
)
238 g_warning("Conversion from uint64 to non precise LttTime");
241 //if(unlikely(t1 >= NANOSECONDS_PER_SECOND)) {
242 if(likely(t1
>>LTT_TIME_UINT_SHIFT
>= LTT_TIME_UINT_SHIFT_CONST
)) {
243 //res.tv_sec = t1/NANOSECONDS_PER_SECOND;
244 res
.tv_sec
= (t1
>>LTT_TIME_UINT_SHIFT
)
245 /LTT_TIME_UINT_SHIFT_CONST
; // acceleration
246 res
.tv_nsec
= (t1
- res
.tv_sec
*NANOSECONDS_PER_SECOND
);
249 res
.tv_nsec
= (guint32
)t1
;