2 Copyright (C) 2001 Paul Davis
3 Code derived from various headers from the Linux kernel
5 This program is free software; you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published by
7 the Free Software Foundation; either version 2 of the License, or
8 (at your option) any later version.
10 This program is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 GNU General Public License for more details.
15 You should have received a copy of the GNU General Public License
16 along with this program; if not, write to the Free Software
17 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
19 $Id: cycles.h,v 1.4.2.1 2006/06/20 14:44:00 letz Exp $
22 #ifndef __jack_cycles_h__
23 #define __jack_cycles_h__
26 * Standard way to access the cycle counter on i586+ CPUs.
27 * Currently only used on SMP.
29 * If you really have a SMP machine with i486 chips or older,
30 * compile for that, and this will just always return zero.
31 * That's ok, it just means that the nicer scheduling heuristics
34 * We only use the low 32 bits, and we'd simply better make sure
35 * that we reschedule before that wraps. Scheduling at least every
36 * four billion cycles just basically sounds like a good idea,
37 * regardless of how fast the machine is.
42 typedef unsigned long cycles_t
;
43 extern cycles_t cacheflush_time
;
45 static inline unsigned long get_cycles(void)
48 __asm__
__volatile__ ("rdtsc" : "=a"(lo
), "=d"(hi
));
49 return (((unsigned long)hi
)<<32) | ((unsigned long)lo
);
52 #endif /* __x86_64__ */
56 static inline unsigned long long get_cycles(void)
58 unsigned long long res
;
59 __asm__
__volatile__("rd %%tick, %0" : "=r"(res
));
62 #endif /* __sparc_v9__ */
68 #define CPU_FTR_601 0x00000100
70 typedef unsigned long cycles_t
;
72 /* For the "cycle" counter we use the timebase lower half. */
74 extern cycles_t cacheflush_time
;
76 static inline cycles_t
get_cycles(void)
83 ".section __ftr_fixup,\"a\"\n"
89 : "=r" (ret
) : "i" (CPU_FTR_601
));
97 typedef unsigned long long cycles_t
;
99 extern cycles_t cacheflush_time
;
101 #define rdtscll(val) \
102 __asm__ __volatile__("rdtsc" : "=A" (val))
104 static inline cycles_t
get_cycles (void)
106 unsigned long long ret
;
112 #endif /* __i386__ */
114 /* everything else but x86, amd64, sparcv9 or ppc */
115 #if !defined (__PPC__) && !defined (__x86_64__) && !defined (__i386__) && !defined (__sparc_v9__)
117 #warning No suitable get_cycles() implementation. Returning 0 instead
119 typedef unsigned long long cycles_t
;
121 static inline cycles_t
get_cycles(void)
126 #endif /* everything else but x86, amd64, sparcv9 or ppc */
129 #endif /* __jack_cycles_h__ */