blob: 12856ff639d020e0e7b06bda135b65fb69b28d09 [file] [log] [blame]
/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License (the "License").
* You may not use this file except in compliance with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or http://www.opensolaris.org/os/licensing.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/*
* Copyright 2008 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*
* Copyright 2018 Joyent, Inc.
*/
/*
* wait.c - asynchronous monitoring of "wait registered" start methods
*
* Use event ports to poll on the set of fds representing the /proc/[pid]/psinfo
* files. If one of these fds returns an event, then we inform the restarter
* that it has stopped.
*
* The wait_info_list holds the series of processes currently being monitored
* for exit. The wi_fd member, which contains the file descriptor of the psinfo
* file being polled upon ("event ported upon"), will be set to -1 if the file
* descriptor is inactive (already closed or not yet opened).
*/
#ifdef _FILE_OFFSET_BITS
#undef _FILE_OFFSET_BITS
#endif /* _FILE_OFFSET_BITS */
#include <sys/resource.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <sys/uio.h>
#include <sys/wait.h>
#include <assert.h>
#include <errno.h>
#include <fcntl.h>
#include <libuutil.h>
#include <poll.h>
#include <port.h>
#include <pthread.h>
#include <procfs.h>
#include <string.h>
#include <stropts.h>
#include <unistd.h>
#include "startd.h"
#define WAIT_FILES 262144 /* reasonably high maximum */
static int port_fd;
static scf_handle_t *wait_hndl;
static struct rlimit init_fd_rlimit;
static uu_list_pool_t *wait_info_pool;
static uu_list_t *wait_info_list;
static pthread_mutex_t wait_info_lock;
/*
* void wait_remove(wait_info_t *, int)
* Remove the given wait_info structure from our list, performing various
* cleanup operations along the way. If the direct flag is false (meaning
* that we are being called with from restarter instance list context) and
* the instance should not be ignored, then notify the restarter that the
* associated instance has exited. If the wi_ignore flag is true then it
* means that the stop was initiated from within svc.startd, rather than
* from outside it.
*
* Since we may no longer be the startd that started this process, we only are
* concerned with a waitpid(3C) failure if the wi_parent field is non-zero.
*/
static void
wait_remove(wait_info_t *wi, int direct)
{
int status;
stop_cause_t cause = RSTOP_EXIT;
if (waitpid(wi->wi_pid, &status, 0) == -1) {
if (wi->wi_parent)
log_framework(LOG_INFO,
"instance %s waitpid failure: %s\n", wi->wi_fmri,
strerror(errno));
} else {
if (WEXITSTATUS(status) != 0) {
log_framework(LOG_NOTICE,
"instance %s exited with status %d\n", wi->wi_fmri,
WEXITSTATUS(status));
if (WEXITSTATUS(status) == SMF_EXIT_ERR_CONFIG)
cause = RSTOP_ERR_CFG;
else
cause = RSTOP_ERR_EXIT;
}
}
MUTEX_LOCK(&wait_info_lock);
if (wi->wi_fd != -1) {
startd_close(wi->wi_fd);
wi->wi_fd = -1;
}
uu_list_remove(wait_info_list, wi);
MUTEX_UNLOCK(&wait_info_lock);
/*
* Make an attempt to clear out any utmpx record associated with this
* PID.
*/
utmpx_mark_dead(wi->wi_pid, status, B_FALSE);
if (!direct && !wi->wi_ignore) {
/*
* Bind wait_hndl lazily.
*/
if (wait_hndl == NULL) {
for (wait_hndl =
libscf_handle_create_bound(SCF_VERSION);
wait_hndl == NULL;
wait_hndl =
libscf_handle_create_bound(SCF_VERSION)) {
log_error(LOG_INFO, "[wait_remove] Unable to "
"bind a new repository handle: %s\n",
scf_strerror(scf_error()));
(void) sleep(2);
}
}
log_framework(LOG_DEBUG,
"wait_remove requesting stop of %s\n", wi->wi_fmri);
(void) stop_instance_fmri(wait_hndl, wi->wi_fmri, cause);
}
uu_list_node_fini(wi, &wi->wi_link, wait_info_pool);
startd_free(wi, sizeof (wait_info_t));
}
/*
* void wait_ignore_by_fmri(const char *)
* wait_ignore_by_fmri is called when svc.startd is going to stop the
* instance. Since we need to wait on the process and close the utmpx record,
* we're going to set the wi_ignore flag, so that when the process exits we
* clean up, but don't tell the restarter to stop it.
*/
void
wait_ignore_by_fmri(const char *fmri)
{
wait_info_t *wi;
MUTEX_LOCK(&wait_info_lock);
for (wi = uu_list_first(wait_info_list); wi != NULL;
wi = uu_list_next(wait_info_list, wi)) {
if (strcmp(wi->wi_fmri, fmri) == 0)
break;
}
if (wi != NULL) {
wi->wi_ignore = 1;
}
MUTEX_UNLOCK(&wait_info_lock);
}
/*
* int wait_register(pid_t, char *, int, int)
* wait_register is called after we have called fork(2), and know which pid we
* wish to monitor. However, since the child may have already exited by the
* time we are called, we must handle the error cases from open(2)
* appropriately. The am_parent flag is recorded to handle waitpid(2)
* behaviour on removal; similarly, the direct flag is passed through to a
* potential call to wait_remove() to govern its behaviour in different
* contexts.
*
* Returns 0 if registration successful, 1 if child pid did not exist, and -1
* if a different error occurred.
*/
int
wait_register(pid_t pid, const char *inst_fmri, int am_parent, int direct)
{
char *fname = uu_msprintf("/proc/%ld/psinfo", pid);
int fd;
wait_info_t *wi;
assert(pid != 0);
if (fname == NULL)
return (-1);
wi = startd_alloc(sizeof (wait_info_t));
uu_list_node_init(wi, &wi->wi_link, wait_info_pool);
wi->wi_fd = -1;
wi->wi_pid = pid;
wi->wi_fmri = inst_fmri;
wi->wi_parent = am_parent;
wi->wi_ignore = 0;
MUTEX_LOCK(&wait_info_lock);
(void) uu_list_insert_before(wait_info_list, NULL, wi);
MUTEX_UNLOCK(&wait_info_lock);
if ((fd = open(fname, O_RDONLY)) == -1) {
if (errno == ENOENT) {
/*
* Child has already exited.
*/
wait_remove(wi, direct);
uu_free(fname);
return (1);
} else {
log_error(LOG_WARNING,
"open %s failed; not monitoring %s: %s\n", fname,
inst_fmri, strerror(errno));
uu_free(fname);
return (-1);
}
}
uu_free(fname);
wi->wi_fd = fd;
if (port_associate(port_fd, PORT_SOURCE_FD, fd, 0, wi)) {
log_error(LOG_WARNING,
"initial port_association of %d / %s failed: %s\n", fd,
inst_fmri, strerror(errno));
return (-1);
}
log_framework(LOG_DEBUG, "monitoring PID %ld on fd %d (%s)\n", pid, fd,
inst_fmri);
return (0);
}
/*ARGSUSED*/
void *
wait_thread(void *args)
{
(void) pthread_setname_np(pthread_self(), "wait");
for (;;) {
port_event_t pe;
int fd;
wait_info_t *wi;
if (port_get(port_fd, &pe, NULL) != 0) {
if (errno == EINTR)
continue;
else {
log_error(LOG_WARNING,
"port_get() failed with %s\n",
strerror(errno));
bad_error("port_get", errno);
}
}
fd = pe.portev_object;
wi = pe.portev_user;
assert(wi != NULL);
assert(fd == wi->wi_fd);
if ((pe.portev_events & POLLHUP) == POLLHUP) {
psinfo_t psi;
if (lseek(fd, 0, SEEK_SET) != 0 ||
read(fd, &psi, sizeof (psinfo_t)) !=
sizeof (psinfo_t)) {
log_framework(LOG_WARNING,
"couldn't get psinfo data for %s (%s); "
"assuming failed\n", wi->wi_fmri,
strerror(errno));
goto err_remove;
}
if (psi.pr_nlwp != 0 ||
psi.pr_nzomb != 0 ||
psi.pr_lwp.pr_lwpid != 0) {
/*
* We have determined, in accordance with the
* definition in proc(4), this process is not a
* zombie. Reassociate.
*/
if (port_associate(port_fd, PORT_SOURCE_FD, fd,
0, wi))
log_error(LOG_WARNING,
"port_association of %d / %s "
"failed\n", fd, wi->wi_fmri);
continue;
}
} else if (
(pe.portev_events & POLLERR) == 0) {
if (port_associate(port_fd, PORT_SOURCE_FD, fd, 0, wi))
log_error(LOG_WARNING,
"port_association of %d / %s "
"failed\n", fd, wi->wi_fmri);
continue;
}
err_remove:
wait_remove(wi, 0);
}
/*LINTED E_FUNC_HAS_NO_RETURN_STMT*/
}
void
wait_prefork()
{
MUTEX_LOCK(&wait_info_lock);
}
void
wait_postfork(pid_t pid)
{
wait_info_t *wi;
MUTEX_UNLOCK(&wait_info_lock);
if (pid != 0)
return;
/*
* Close all of the child's wait-related fds. The wait_thread() is
* gone, so no need to worry about returning events. We always exec(2)
* after a fork request, so we needn't free the list elements
* themselves.
*/
for (wi = uu_list_first(wait_info_list);
wi != NULL;
wi = uu_list_next(wait_info_list, wi)) {
if (wi->wi_fd != -1)
startd_close(wi->wi_fd);
}
startd_close(port_fd);
(void) setrlimit(RLIMIT_NOFILE, &init_fd_rlimit);
}
void
wait_init()
{
struct rlimit fd_new;
(void) getrlimit(RLIMIT_NOFILE, &init_fd_rlimit);
(void) getrlimit(RLIMIT_NOFILE, &fd_new);
fd_new.rlim_max = fd_new.rlim_cur = WAIT_FILES;
(void) setrlimit(RLIMIT_NOFILE, &fd_new);
if ((port_fd = port_create()) == -1)
uu_die("wait_init couldn't port_create");
wait_info_pool = uu_list_pool_create("wait_info", sizeof (wait_info_t),
offsetof(wait_info_t, wi_link), NULL, UU_LIST_POOL_DEBUG);
if (wait_info_pool == NULL)
uu_die("wait_init couldn't create wait_info_pool");
wait_info_list = uu_list_create(wait_info_pool, wait_info_list, 0);
if (wait_info_list == NULL)
uu_die("wait_init couldn't create wait_info_list");
(void) pthread_mutex_init(&wait_info_lock, &mutex_attrs);
}