pmckern.h revision 148562 
1/*-
2 * Copyright (c) 2003-2005, Joseph Koshy
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 *
26 * $FreeBSD: head/sys/sys/pmckern.h 148562 2005-07-30 09:02:42Z jkoshy $
27 */
28
29/*
30 * PMC interface used by the base kernel.
31 */
32
33#ifndef _SYS_PMCKERN_H_
34#define _SYS_PMCKERN_H_
35
36#include <sys/param.h>
37#include <sys/kernel.h>
38#include <sys/lock.h>
39#include <sys/proc.h>
40#include <sys/sx.h>
41
42#define	PMC_FN_PROCESS_EXEC		1
43#define	PMC_FN_CSW_IN			2
44#define	PMC_FN_CSW_OUT			3
45#define	PMC_FN_DO_SAMPLES		4
46
47struct pmckern_procexec {
48	int		pm_credentialschanged;
49	uintptr_t	pm_entryaddr;
50};
51
52/* hook */
53extern int (*pmc_hook)(struct thread *_td, int _function, void *_arg);
54extern int (*pmc_intr)(int _cpu, uintptr_t _pc, int _usermode);
55
56/* SX lock protecting the hook */
57extern struct sx pmc_sx;
58
59/* Per-cpu flags indicating availability of sampling data */
60extern volatile cpumask_t pmc_cpumask;
61
62/* Count of system-wide sampling PMCs in existence */
63extern volatile int pmc_ss_count;
64
65/* kernel version number */
66extern const int pmc_kernel_version;
67
68/* Hook invocation; for use within the kernel */
69#define	PMC_CALL_HOOK(t, cmd, arg)		\
70do {						\
71	sx_slock(&pmc_sx);			\
72	if (pmc_hook != NULL)			\
73		(pmc_hook)((t), (cmd), (arg));	\
74	sx_sunlock(&pmc_sx);			\
75} while (0)
76
77/* Hook invocation that needs an exclusive lock */
78#define	PMC_CALL_HOOK_X(t, cmd, arg)		\
79do {						\
80	sx_xlock(&pmc_sx);			\
81	if (pmc_hook != NULL)			\
82		(pmc_hook)((t), (cmd), (arg));	\
83	sx_xunlock(&pmc_sx);			\
84} while (0)
85
86/*
87 * Some hook invocations (e.g., from context switch and clock handling
88 * code) need to be lock-free.
89 */
90#define	PMC_CALL_HOOK_UNLOCKED(t, cmd, arg)	\
91do {						\
92	if (pmc_hook != NULL)			\
93		(pmc_hook)((t), (cmd), (arg));	\
94} while (0)
95
96#define	PMC_SWITCH_CONTEXT(t,cmd)	PMC_CALL_HOOK_UNLOCKED(t,cmd,NULL)
97
98/* Check if a process is using HWPMCs.*/
99#define PMC_PROC_IS_USING_PMCS(p)				\
100	(__predict_false(atomic_load_acq_int(&(p)->p_flag) &	\
101	    P_HWPMC))
102
103#define	PMC_SYSTEM_SAMPLING_ACTIVE()		(pmc_ss_count > 0)
104
105/* Check if a CPU has recorded samples. */
106#define	PMC_CPU_HAS_SAMPLES(C)	(__predict_false(pmc_cpumask & (1 << (C))))
107
108/* helper functions */
109int	pmc_cpu_is_disabled(int _cpu);
110int	pmc_cpu_is_logical(int _cpu);
111
112#endif /* _SYS_PMCKERN_H_ */
113