xref: /freebsd/sys/ddb/db_thread.c (revision a466cc55373fc3cf86837f09da729535b57e69a1)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2004 Marcel Moolenaar
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  *
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27  */
28 
29 #include <sys/cdefs.h>
30 __FBSDID("$FreeBSD$");
31 
32 #include <sys/param.h>
33 #include <sys/systm.h>
34 #include <sys/kdb.h>
35 #include <sys/proc.h>
36 
37 #include <machine/pcb.h>
38 
39 #include <ddb/ddb.h>
40 #include <ddb/db_command.h>
41 #include <ddb/db_sym.h>
42 
43 void
44 db_print_thread(void)
45 {
46 	pid_t pid;
47 
48 	pid = -1;
49 	if (kdb_thread->td_proc != NULL)
50 		pid = kdb_thread->td_proc->p_pid;
51 	db_printf("[ thread pid %d tid %ld ]\n", pid, (long)kdb_thread->td_tid);
52 }
53 
54 void
55 db_set_thread(db_expr_t tid, bool hastid, db_expr_t cnt, char *mod)
56 {
57 	struct thread *thr;
58 	int err;
59 
60 	if (hastid) {
61 		thr = db_lookup_thread(tid, false);
62 		if (thr != NULL) {
63 			err = kdb_thr_select(thr);
64 			if (err != 0) {
65 				db_printf("unable to switch to thread %ld\n",
66 				    (long)thr->td_tid);
67 				return;
68 			}
69 			db_dot = PC_REGS();
70 		} else {
71 			db_printf("%d: invalid thread\n", (int)tid);
72 			return;
73 		}
74 	}
75 
76 	db_print_thread();
77 	db_print_loc_and_inst(PC_REGS());
78 }
79 
80 void
81 db_show_threads(db_expr_t addr, bool hasaddr, db_expr_t cnt, char *mod)
82 {
83 	jmp_buf jb;
84 	void *prev_jb;
85 	struct thread *thr;
86 
87 	thr = kdb_thr_first();
88 	while (!db_pager_quit && thr != NULL) {
89 		db_printf("  %6ld (%p) (stack %p)  ", (long)thr->td_tid, thr,
90 		    (void *)thr->td_kstack);
91 		prev_jb = kdb_jmpbuf(jb);
92 		if (setjmp(jb) == 0) {
93 			if (thr->td_proc->p_flag & P_INMEM) {
94 				if (db_trace_thread(thr, 1) != 0)
95 					db_printf("***\n");
96 			} else
97 				db_printf("*** swapped out\n");
98 		}
99 		kdb_jmpbuf(prev_jb);
100 		thr = kdb_thr_next(thr);
101 	}
102 }
103 
104 /*
105  * Lookup a thread based on a db expression address.  We assume that the
106  * address was parsed in hexadecimal.  We reparse the address in decimal
107  * first and try to treat it as a thread ID to find an associated thread.
108  * If that fails and check_pid is true, we treat the decimal value as a
109  * PID.  If that matches a process, we return the first thread in that
110  * process.  Otherwise, we treat the addr as a pointer to a thread.
111  */
112 struct thread *
113 db_lookup_thread(db_expr_t addr, bool check_pid)
114 {
115 	struct thread *td;
116 	db_expr_t decaddr;
117 
118 	/*
119 	 * If the parsed address was not a valid decimal expression,
120 	 * assume it is a thread pointer.
121 	 */
122 	decaddr = db_hex2dec(addr);
123 	if (decaddr == -1)
124 		return ((struct thread *)addr);
125 
126 	td = kdb_thr_lookup(decaddr);
127 	if (td != NULL)
128 		return (td);
129 	if (check_pid) {
130 		td = kdb_thr_from_pid(decaddr);
131 		if (td != NULL)
132 			return (td);
133 	}
134 	return ((struct thread *)addr);
135 }
136 
137 /*
138  * Lookup a process based on a db expression address.  We assume that the
139  * address was parsed in hexadecimal.  We reparse the address in decimal
140  * first and try to treat it as a PID to find an associated process.
141  * If that fails we treat the addr as a pointer to a process.
142  */
143 struct proc *
144 db_lookup_proc(db_expr_t addr)
145 {
146 	db_expr_t decaddr;
147 	struct proc *p;
148 
149 	decaddr = db_hex2dec(addr);
150 	if (decaddr != -1) {
151 		LIST_FOREACH(p, PIDHASH(decaddr), p_hash) {
152 			if (p->p_pid == decaddr)
153 				return (p);
154 		}
155 	}
156 	return ((struct proc *)addr);
157 }
158