1 /*- 2 * Copyright (c) 2007-2008 John Birrell <jb@FreeBSD.org> 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 27 #include <sys/cdefs.h> 28 __FBSDID("$FreeBSD$"); 29 30 #include "opt_kdb.h" 31 32 #include <sys/param.h> 33 #include <sys/systm.h> 34 #include <sys/eventhandler.h> 35 #include <sys/kdb.h> 36 #include <sys/kernel.h> 37 #include <sys/malloc.h> 38 #include <sys/proc.h> 39 #include <sys/dtrace_bsd.h> 40 41 #define KDTRACE_PROC_SIZE 64 42 #define KDTRACE_PROC_ZERO 8 43 #define KDTRACE_THREAD_SIZE 256 44 #define KDTRACE_THREAD_ZERO 64 45 46 MALLOC_DEFINE(M_KDTRACE, "kdtrace", "DTrace hooks"); 47 48 /* Return the DTrace process data size compiled in the kernel hooks. */ 49 size_t 50 kdtrace_proc_size() 51 { 52 return(KDTRACE_PROC_SIZE); 53 } 54 55 static void 56 kdtrace_proc_ctor(void *arg __unused, struct proc *p) 57 { 58 p->p_dtrace = malloc(KDTRACE_PROC_SIZE, M_KDTRACE, M_WAITOK); 59 60 bzero(p->p_dtrace, KDTRACE_PROC_ZERO); 61 } 62 63 static void 64 kdtrace_proc_dtor(void *arg __unused, struct proc *p) 65 { 66 if (p->p_dtrace != NULL) { 67 free(p->p_dtrace, M_KDTRACE); 68 p->p_dtrace = NULL; 69 } 70 } 71 72 /* Return the DTrace thread data size compiled in the kernel hooks. */ 73 size_t 74 kdtrace_thread_size() 75 { 76 return(KDTRACE_THREAD_SIZE); 77 } 78 79 static void 80 kdtrace_thread_ctor(void *arg __unused, struct thread *td) 81 { 82 td->td_dtrace = malloc(KDTRACE_THREAD_SIZE, M_KDTRACE, M_WAITOK); 83 84 bzero(td->td_dtrace, KDTRACE_THREAD_ZERO); 85 } 86 87 static void 88 kdtrace_thread_dtor(void *arg __unused, struct thread *td) 89 { 90 if (td->td_dtrace != NULL) { 91 free(td->td_dtrace, M_KDTRACE); 92 td->td_dtrace = NULL; 93 } 94 } 95 96 /* 97 * Initialise the kernel DTrace hooks. 98 */ 99 static void 100 init_dtrace(void *dummy __unused) 101 { 102 EVENTHANDLER_REGISTER(process_ctor, kdtrace_proc_ctor, NULL, EVENTHANDLER_PRI_ANY); 103 EVENTHANDLER_REGISTER(process_dtor, kdtrace_proc_dtor, NULL, EVENTHANDLER_PRI_ANY); 104 EVENTHANDLER_REGISTER(thread_ctor, kdtrace_thread_ctor, NULL, EVENTHANDLER_PRI_ANY); 105 EVENTHANDLER_REGISTER(thread_dtor, kdtrace_thread_dtor, NULL, EVENTHANDLER_PRI_ANY); 106 } 107 108 SYSINIT(kdtrace, SI_SUB_KDTRACE, SI_ORDER_FIRST, init_dtrace, NULL); 109