freebsd-skq/sys/ddb/db_thread.c
cem 9623f41702 ddb: Enable 'thread <address>'
Currently, the 'thread' command (to switch the debugger to another thread)
only accepts decimal-encoded tids.  Use the same parsing logic as 'show
thread <arg>' to accept hex-encoded thread pointers in addition to
decimal-encoded tids.

Document the 'thread' command in ddb.4 and expand the 'show thread'
documentation to cover the tid usage.

Reported by:	bwidawsk
Reviewed by:	bwidawsk (earlier version), kib (earlier version), markj
Sponsored by:	Dell EMC Isilon
Differential Revision:	https://reviews.freebsd.org/D16962
2018-10-20 20:45:49 +00:00

165 lines
4.4 KiB
C

/*-
* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
*
* Copyright (c) 2004 Marcel Moolenaar
* 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 ``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 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 <sys/param.h>
#include <sys/systm.h>
#include <sys/kdb.h>
#include <sys/proc.h>
#include <machine/pcb.h>
#include <ddb/ddb.h>
#include <ddb/db_command.h>
#include <ddb/db_sym.h>
void
db_print_thread(void)
{
pid_t pid;
pid = -1;
if (kdb_thread->td_proc != NULL)
pid = kdb_thread->td_proc->p_pid;
db_printf("[ thread pid %d tid %ld ]\n", pid, (long)kdb_thread->td_tid);
}
void
db_set_thread(db_expr_t tid, bool hastid, db_expr_t cnt, char *mod)
{
struct thread *thr;
int err;
if (hastid) {
thr = db_lookup_thread(tid, false);
if (thr != NULL) {
err = kdb_thr_select(thr);
if (err != 0) {
db_printf("unable to switch to thread %ld\n",
(long)thr->td_tid);
return;
}
db_dot = PC_REGS();
} else {
db_printf("%d: invalid thread\n", (int)tid);
return;
}
}
db_print_thread();
db_print_loc_and_inst(PC_REGS());
}
void
db_show_threads(db_expr_t addr, bool hasaddr, db_expr_t cnt, char *mod)
{
jmp_buf jb;
void *prev_jb;
struct thread *thr;
thr = kdb_thr_first();
while (!db_pager_quit && thr != NULL) {
db_printf(" %6ld (%p) (stack %p) ", (long)thr->td_tid, thr,
(void *)thr->td_kstack);
prev_jb = kdb_jmpbuf(jb);
if (setjmp(jb) == 0) {
if (db_trace_thread(thr, 1) != 0)
db_printf("***\n");
}
kdb_jmpbuf(prev_jb);
thr = kdb_thr_next(thr);
}
}
/*
* Lookup a thread based on a db expression address. We assume that the
* address was parsed in hexadecimal. We reparse the address in decimal
* first and try to treat it as a thread ID to find an associated thread.
* If that fails and check_pid is true, we treat the decimal value as a
* PID. If that matches a process, we return the first thread in that
* process. Otherwise, we treat the addr as a pointer to a thread.
*/
struct thread *
db_lookup_thread(db_expr_t addr, bool check_pid)
{
struct thread *td;
db_expr_t decaddr;
struct proc *p;
/*
* If the parsed address was not a valid decimal expression,
* assume it is a thread pointer.
*/
decaddr = db_hex2dec(addr);
if (decaddr == -1)
return ((struct thread *)addr);
td = kdb_thr_lookup(decaddr);
if (td != NULL)
return (td);
if (check_pid) {
FOREACH_PROC_IN_SYSTEM(p) {
if (p->p_pid == decaddr)
return (FIRST_THREAD_IN_PROC(p));
}
LIST_FOREACH(p, &zombproc, p_list) {
if (p->p_pid == decaddr)
return (FIRST_THREAD_IN_PROC(p));
}
}
return ((struct thread *)addr);
}
/*
* Lookup a process based on a db expression address. We assume that the
* address was parsed in hexadecimal. We reparse the address in decimal
* first and try to treat it as a PID to find an associated process.
* If that fails we treat the addr as a pointer to a process.
*/
struct proc *
db_lookup_proc(db_expr_t addr)
{
db_expr_t decaddr;
struct proc *p;
decaddr = db_hex2dec(addr);
if (decaddr != -1) {
FOREACH_PROC_IN_SYSTEM(p) {
if (p->p_pid == decaddr)
return (p);
}
LIST_FOREACH(p, &zombproc, p_list) {
if (p->p_pid == decaddr)
return (p);
}
}
return ((struct proc *)addr);
}