xref: /freebsd/sys/kern/kern_pmc.c (revision 7afc53b8dfcc7d5897920ce6cc7e842fbb4ab813)
1 /*-
2  * Copyright (c) 2003-2005, Joseph Koshy
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that the following conditions
6  * are met:
7  * 1. Redistributions of source code must retain the above copyright
8  *    notice, this list of conditions and the following disclaimer.
9  * 2. Redistributions in binary form must reproduce the above copyright
10  *    notice, this list of conditions and the following disclaimer in the
11  *    documentation and/or other materials provided with the distribution.
12  *
13  * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND
14  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
16  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE
17  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
18  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
19  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
20  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
21  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
22  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
23  * SUCH DAMAGE.
24  */
25 
26 #include <sys/cdefs.h>
27 __FBSDID("$FreeBSD$");
28 
29 #include <sys/pmckern.h>
30 #include <sys/smp.h>
31 
32 struct sx pmc_sx;
33 
34 /* Hook variable. */
35 int (*pmc_hook)(struct thread *td, int function, void *arg) = NULL;
36 
37 /* Interrupt handler */
38 int (*pmc_intr)(int cpu, uintptr_t pc, int usermode) = NULL;
39 
40 cpumask_t pmc_cpumask;
41 
42 /*
43  * Since PMC(4) may not be loaded in the current kernel, the
44  * convention followed is that a non-NULL value of 'pmc_hook' implies
45  * the presence of this kernel module.
46  *
47  * This requires us to protect 'pmc_hook' with a
48  * shared (sx) lock -- thus making the process of calling into PMC(4)
49  * somewhat more expensive than a simple 'if' check and indirect call.
50  */
51 
52 
53 SX_SYSINIT(pmc, &pmc_sx, "pmc shared lock");
54 
55 /*
56  * pmc_cpu_is_disabled
57  *
58  * return TRUE if the cpu specified has been disabled.
59  */
60 
61 int
62 pmc_cpu_is_disabled(int cpu)
63 {
64 #ifdef	SMP
65 	return ((hlt_cpus_mask & (1 << cpu)) != 0);
66 #else
67 	return 0;
68 #endif
69 }
70 
71 int
72 pmc_cpu_is_logical(int cpu)
73 {
74 #ifdef	SMP
75 	return ((logical_cpus_mask & (1 << cpu)) != 0);
76 #else
77 	return 0;
78 #endif
79 }
80