xref: /freebsd/stand/libsa/tslog.c (revision e6caac717b4fc2b87cf93f67109884e768253e77)
1e193d3baSColin Percival /*-
2e193d3baSColin Percival  * Copyright (c) 2021 Colin Percival
3e193d3baSColin Percival  * All rights reserved.
4e193d3baSColin Percival  *
5e193d3baSColin Percival  * Redistribution and use in source and binary forms, with or without
6e193d3baSColin Percival  * modification, are permitted provided that the following conditions
7e193d3baSColin Percival  * are met:
8e193d3baSColin Percival  * 1. Redistributions of source code must retain the above copyright
9e193d3baSColin Percival  *    notice, this list of conditions and the following disclaimer.
10e193d3baSColin Percival  * 2. Redistributions in binary form must reproduce the above copyright
11e193d3baSColin Percival  *    notice, this list of conditions and the following disclaimer in the
12e193d3baSColin Percival  *    documentation and/or other materials provided with the distribution.
13e193d3baSColin Percival  *
14e193d3baSColin Percival  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15e193d3baSColin Percival  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16e193d3baSColin Percival  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17e193d3baSColin Percival  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18e193d3baSColin Percival  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19e193d3baSColin Percival  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20e193d3baSColin Percival  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21e193d3baSColin Percival  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22e193d3baSColin Percival  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23e193d3baSColin Percival  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24e193d3baSColin Percival  * SUCH DAMAGE.
25e193d3baSColin Percival  */
26e193d3baSColin Percival 
27e193d3baSColin Percival #include <sys/cdefs.h>
28e193d3baSColin Percival __FBSDID("$FreeBSD$");
29e193d3baSColin Percival 
30e193d3baSColin Percival #include <sys/types.h>
31e193d3baSColin Percival 
32*e6caac71SColin Percival #if defined(__amd64__) || defined(__i386__)
33e193d3baSColin Percival #include <machine/cpufunc.h>
34*e6caac71SColin Percival #elif defined(__aarch64__)
35*e6caac71SColin Percival #include <machine/armreg.h>
36*e6caac71SColin Percival #endif
37e193d3baSColin Percival 
38e193d3baSColin Percival #include <stand.h>
39e193d3baSColin Percival 
40e193d3baSColin Percival /* Buffer for holding tslog data in string format. */
41e193d3baSColin Percival static char * tslog_buf = NULL;
42e193d3baSColin Percival static size_t tslog_buflen = 0;
43e193d3baSColin Percival static size_t tslog_bufpos = 0;
44e193d3baSColin Percival 
45e193d3baSColin Percival void
46e193d3baSColin Percival tslog_setbuf(void * buf, size_t len)
47e193d3baSColin Percival {
48e193d3baSColin Percival 
49e193d3baSColin Percival 	tslog_buf = (char *)buf;
50e193d3baSColin Percival 	tslog_buflen = len;
51e193d3baSColin Percival 	tslog_bufpos = 0;
52e193d3baSColin Percival }
53e193d3baSColin Percival 
54e193d3baSColin Percival void
55e193d3baSColin Percival tslog_getbuf(void ** buf, size_t * len)
56e193d3baSColin Percival {
57e193d3baSColin Percival 
58e193d3baSColin Percival 	*buf = (void *)tslog_buf;
59e193d3baSColin Percival 	*len = tslog_bufpos;
60e193d3baSColin Percival }
61e193d3baSColin Percival 
62e193d3baSColin Percival void
63e193d3baSColin Percival tslog(const char * type, const char * f, const char * s)
64e193d3baSColin Percival {
65e193d3baSColin Percival #if defined(__amd64__) || defined(__i386__)
66e193d3baSColin Percival 	uint64_t tsc = rdtsc();
67*e6caac71SColin Percival #elif defined(__aarch64__)
68*e6caac71SColin Percival 	uint64_t tsc = READ_SPECIALREG(cntvct_el0);
69e193d3baSColin Percival #else
70e193d3baSColin Percival 	uint64_t tsc = 0;
71e193d3baSColin Percival #endif
72e193d3baSColin Percival 	int len;
73e193d3baSColin Percival 
74e193d3baSColin Percival 	/* If we have no buffer, do nothing. */
75e193d3baSColin Percival 	if (tslog_buf == NULL)
76e193d3baSColin Percival 		return;
77e193d3baSColin Percival 
78e193d3baSColin Percival 	/* Append to existing buffer, if we have enough space. */
79e193d3baSColin Percival 	len = snprintf(&tslog_buf[tslog_bufpos],
80e193d3baSColin Percival 	    tslog_buflen - tslog_bufpos, "0x0 %llu %s %s%s%s\n",
81e193d3baSColin Percival 	    (unsigned long long)tsc, type, f, s ? " " : "", s ? s : "");
82e193d3baSColin Percival 	if ((len > 0) && (tslog_bufpos + len <= tslog_buflen))
83e193d3baSColin Percival 		tslog_bufpos += len;
84e193d3baSColin Percival }
85