freebsd-dev/sys/kern/kern_dtrace.c
Pedro F. Giffuni 8a36da99de sys/kern: adoption of SPDX licensing ID tags.
Mainly focus on files that use BSD 2-Clause license, however the tool I
was using misidentified many licenses so this was mostly a manual - error
prone - task.

The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.
2017-11-27 15:20:12 +00:00

129 lines
3.6 KiB
C

/*-
* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
*
* Copyright (c) 2007-2008 John Birrell <jb@FreeBSD.org>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include "opt_kdb.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/eventhandler.h>
#include <sys/kdb.h>
#include <sys/kernel.h>
#include <sys/malloc.h>
#include <sys/proc.h>
#include <sys/dtrace_bsd.h>
#include <sys/sysctl.h>
#include <sys/sysent.h>
#define KDTRACE_PROC_SIZE 64
#define KDTRACE_THREAD_SIZE 256
FEATURE(kdtrace_hooks,
"Kernel DTrace hooks which are required to load DTrace kernel modules");
static MALLOC_DEFINE(M_KDTRACE, "kdtrace", "DTrace hooks");
/* Hooks used in the machine-dependent trap handlers. */
dtrace_trap_func_t dtrace_trap_func;
dtrace_doubletrap_func_t dtrace_doubletrap_func;
dtrace_pid_probe_ptr_t dtrace_pid_probe_ptr;
dtrace_return_probe_ptr_t dtrace_return_probe_ptr;
systrace_probe_func_t __read_frequently systrace_probe_func;
/* Return the DTrace process data size compiled in the kernel hooks. */
size_t
kdtrace_proc_size()
{
return (KDTRACE_PROC_SIZE);
}
static void
kdtrace_proc_ctor(void *arg __unused, struct proc *p)
{
p->p_dtrace = malloc(KDTRACE_PROC_SIZE, M_KDTRACE, M_WAITOK|M_ZERO);
}
static void
kdtrace_proc_dtor(void *arg __unused, struct proc *p)
{
if (p->p_dtrace != NULL) {
free(p->p_dtrace, M_KDTRACE);
p->p_dtrace = NULL;
}
}
/* Return the DTrace thread data size compiled in the kernel hooks. */
size_t
kdtrace_thread_size()
{
return (KDTRACE_THREAD_SIZE);
}
static void
kdtrace_thread_ctor(void *arg __unused, struct thread *td)
{
td->td_dtrace = malloc(KDTRACE_THREAD_SIZE, M_KDTRACE, M_WAITOK|M_ZERO);
}
static void
kdtrace_thread_dtor(void *arg __unused, struct thread *td)
{
if (td->td_dtrace != NULL) {
free(td->td_dtrace, M_KDTRACE);
td->td_dtrace = NULL;
}
}
/*
* Initialise the kernel DTrace hooks.
*/
static void
init_dtrace(void *dummy __unused)
{
EVENTHANDLER_REGISTER(process_ctor, kdtrace_proc_ctor, NULL,
EVENTHANDLER_PRI_ANY);
EVENTHANDLER_REGISTER(process_dtor, kdtrace_proc_dtor, NULL,
EVENTHANDLER_PRI_ANY);
EVENTHANDLER_REGISTER(thread_ctor, kdtrace_thread_ctor, NULL,
EVENTHANDLER_PRI_ANY);
EVENTHANDLER_REGISTER(thread_dtor, kdtrace_thread_dtor, NULL,
EVENTHANDLER_PRI_ANY);
}
SYSINIT(kdtrace, SI_SUB_KDTRACE, SI_ORDER_FIRST, init_dtrace, NULL);