/*
- * Manipulation routines for Job Control Records
+ * Manipulation routines for Job Control Records and
+ * handling of last_jobs_list.
*
* Kern E. Sibbald, December 2000
*
*
* These routines are thread safe.
*
+ * The job list routines were re-written in May 2005 to
+ * eliminate the global lock while traversing the list, and
+ * to use the dlist subroutines. The locking is now done
+ * on the list each time the list is modified or traversed.
+ * That is it is "micro-locked" rather than globally locked.
+ * The result is that there is one lock/unlock for each entry
+ * in the list while traversing it rather than a single lock
+ * at the beginning of a traversal and one at the end. This
+ * incurs slightly more overhead, but effectively eliminates
+ * the possibilty of race conditions. In addition, with the
+ * exception of the global locking of the list during the
+ * re-reading of the config file, no recursion is needed.
+ *
*/
/*
Copyright (C) 2000-2005 Kern Sibbald
This program is free software; you can redistribute it and/or
- modify it under the terms of the GNU General Public License as
- published by the Free Software Foundation; either version 2 of
- the License, or (at your option) any later version.
+ modify it under the terms of the GNU General Public License
+ version 2 as amended with additional clauses defined in the
+ file LICENSE in the main source directory.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- General Public License for more details.
-
- You should have received a copy of the GNU General Public
- License along with this program; if not, write to the Free
- Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
- MA 02111-1307, USA.
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ the file LICENSE for additional details.
*/
/* Forward referenced functions */
extern "C" void timeout_handler(int sig);
-
static void jcr_timeout_check(watchdog_t *self);
+#ifdef TRACE_JCR_CHAIN
+static void b_lock_jcr_chain(const char *filen, int line);
+static void b_unlock_jcr_chain(const char *filen, int line);
+#define lock_jcr_chain() b_lock_jcr_chain(__FILE__, __LINE__);
+#define unlock_jcr_chain() b_unlock_jcr_chain(__FILE__, __LINE__);
+#else
+static void lock_jcr_chain();
+static void unlock_jcr_chain();
+#endif
+
int num_jobs_run;
dlist *last_jobs = NULL;
const int max_last_jobs = 10;
+
+static dlist *jcrs = NULL; /* JCR chain */
+static pthread_mutex_t jcr_lock = PTHREAD_MUTEX_INITIALIZER;
-JCR *jobs = NULL; /* pointer to JCR chain */
-static brwlock_t lock; /* lock for last jobs and JCR chain */
+static pthread_mutex_t job_start_mutex = PTHREAD_MUTEX_INITIALIZER;
+
+void lock_jobs()
+{
+ P(job_start_mutex);
+}
+
+void unlock_jobs()
+{
+ V(job_start_mutex);
+}
void init_last_jobs_list()
{
- int errstat;
+ JCR *jcr = NULL;
struct s_last_job *job_entry = NULL;
if (!last_jobs) {
last_jobs = New(dlist(job_entry, &job_entry->link));
- if ((errstat=rwl_init(&lock)) != 0) {
- Emsg1(M_ABORT, 0, _("Unable to initialize jcr_chain lock. ERR=%s\n"),
- strerror(errstat));
- }
}
-
+ if (!jcrs) {
+ jcrs = New(dlist(jcr, &jcr->link));
+ }
}
void term_last_jobs_list()
}
delete last_jobs;
last_jobs = NULL;
- rwl_destroy(&lock);
+ }
+ if (jcrs) {
+ delete jcrs;
+ jcrs = NULL;
}
}
-void read_last_jobs_list(int fd, uint64_t addr)
+bool read_last_jobs_list(int fd, uint64_t addr)
{
struct s_last_job *je, job;
uint32_t num;
Dmsg1(100, "read_last_jobs seek to %d\n", (int)addr);
if (addr == 0 || lseek(fd, (off_t)addr, SEEK_SET) < 0) {
- return;
+ return false;
}
if (read(fd, &num, sizeof(num)) != sizeof(num)) {
- return;
+ return false;
}
Dmsg1(100, "Read num_items=%d\n", num);
if (num > 4 * max_last_jobs) { /* sanity check */
- return;
+ return false;
}
for ( ; num; num--) {
if (read(fd, &job, sizeof(job)) != sizeof(job)) {
Dmsg1(000, "Read job entry. ERR=%s\n", strerror(errno));
- return;
+ return false;
}
if (job.JobId > 0) {
je = (struct s_last_job *)malloc(sizeof(struct s_last_job));
}
}
}
+ return true;
}
uint64_t write_last_jobs_list(int fd, uint64_t addr)
sigfillset(&sigtimer.sa_mask);
sigaction(TIMEOUT_SIGNAL, &sigtimer, NULL);
+ /*
+ * Locking jobs is a global lock that is needed
+ * so that the Director can stop new jobs from being
+ * added to the jcr chain while it processes a new
+ * conf file and does the job_end_push().
+ */
+ lock_jobs();
lock_jcr_chain();
- jcr->prev = NULL;
- jcr->next = jobs;
- if (jobs) {
- jobs->prev = jcr;
+ if (!jcrs) {
+ jcrs = New(dlist(jcr, &jcr->link));
}
- jobs = jcr;
+ jcrs->append(jcr);
unlock_jcr_chain();
+ unlock_jobs();
+
return jcr;
}
{
Dmsg0(3400, "Enter remove_jcr\n");
if (!jcr) {
- Emsg0(M_ABORT, 0, "NULL jcr.\n");
- }
- if (!jcr->prev) { /* if no prev */
- jobs = jcr->next; /* set new head */
- } else {
- jcr->prev->next = jcr->next; /* update prev */
- }
- if (jcr->next) {
- jcr->next->prev = jcr->prev;
+ Emsg0(M_ABORT, 0, _("NULL jcr.\n"));
}
+ jcrs->remove(jcr);
Dmsg0(3400, "Leave remove_jcr\n");
}
case JT_BACKUP:
case JT_VERIFY:
case JT_RESTORE:
+ case JT_MIGRATE:
+ case JT_COPY:
case JT_ADMIN:
num_jobs_run++;
last_job.Errors = jcr->Errors;
jcr->client_name = NULL;
}
+ if (jcr->attr) {
+ free_pool_memory(jcr->attr);
+ jcr->attr = NULL;
+ }
+
if (jcr->sd_auth_key) {
free(jcr->sd_auth_key);
jcr->sd_auth_key = NULL;
#endif
dequeue_messages(jcr);
- if (jcr->JobId != 0) {
- generate_daemon_event(jcr, "JobEnd");
- }
lock_jcr_chain();
- jcr->use_count--; /* decrement use count */
+ jcr->dec_use_count(); /* decrement use count */
if (jcr->use_count < 0) {
Emsg2(M_ERROR, 0, _("JCR use_count=%d JobId=%d\n"),
jcr->use_count, jcr->JobId);
Dmsg2(3400, "free_jcr 0x%x use_count=%d\n", jcr, jcr->use_count);
return;
}
+
remove_jcr(jcr); /* remove Jcr from chain */
unlock_jcr_chain();
}
-/*
- * Global routine to free a jcr
- * JCR chain is already locked
- */
-void free_locked_jcr(JCR *jcr)
-{
- jcr->use_count--; /* decrement use count */
- Dmsg2(3400, "Dec free_locked_jcr 0x%x use_count=%d\n", jcr, jcr->use_count);
- if (jcr->use_count > 0) { /* if in use */
- return;
- }
- remove_jcr(jcr);
- jcr->daemon_free_jcr(jcr); /* call daemon free routine */
- free_common_jcr(jcr);
-}
-
-
-
/*
* Given a JobId, find the JCR
* Returns: jcr on success
JCR *jcr;
lock_jcr_chain(); /* lock chain */
- for (jcr = jobs; jcr; jcr=jcr->next) {
+ foreach_dlist(jcr, jcrs) {
if (jcr->JobId == JobId) {
- P(jcr->mutex);
- jcr->use_count++;
- V(jcr->mutex);
+ jcr->inc_use_count();
Dmsg2(3400, "Inc get_jcr 0x%x use_count=%d\n", jcr, jcr->use_count);
break;
}
JCR *jcr;
lock_jcr_chain();
- for (jcr = jobs; jcr; jcr=jcr->next) {
+ foreach_dlist(jcr, jcrs) {
if (jcr->VolSessionId == SessionId &&
jcr->VolSessionTime == SessionTime) {
- P(jcr->mutex);
- jcr->use_count++;
- V(jcr->mutex);
+ jcr->inc_use_count();
Dmsg2(3400, "Inc get_jcr 0x%x use_count=%d\n", jcr, jcr->use_count);
break;
}
}
lock_jcr_chain();
len = strlen(Job);
- for (jcr = jobs; jcr; jcr=jcr->next) {
+ foreach_dlist(jcr, jcrs) {
if (strncmp(Job, jcr->Job, len) == 0) {
- P(jcr->mutex);
- jcr->use_count++;
- V(jcr->mutex);
+ jcr->inc_use_count();
Dmsg2(3400, "Inc get_jcr 0x%x use_count=%d\n", jcr, jcr->use_count);
break;
}
return NULL;
}
lock_jcr_chain();
- for (jcr = jobs; jcr; jcr=jcr->next) {
+ foreach_dlist(jcr, jcrs) {
if (strcmp(jcr->Job, Job) == 0) {
- P(jcr->mutex);
- jcr->use_count++;
- V(jcr->mutex);
+ jcr->inc_use_count();
Dmsg2(3400, "Inc get_jcr 0x%x use_count=%d\n", jcr, jcr->use_count);
break;
}
* Lock the chain
*/
#ifdef TRACE_JCR_CHAIN
-void b_lock_jcr_chain(const char *fname, int line)
+static void b_lock_jcr_chain(const char *fname, int line)
#else
-void lock_jcr_chain()
+static void lock_jcr_chain()
#endif
{
- int errstat;
#ifdef TRACE_JCR_CHAIN
Dmsg3(3400, "Lock jcr chain %d from %s:%d\n", ++lock_count,
fname, line);
#endif
- if ((errstat=rwl_writelock(&lock)) != 0) {
- Emsg1(M_ABORT, 0, "rwl_writelock failure. ERR=%s\n",
- strerror(errstat));
- }
+ P(jcr_lock);
}
/*
* Unlock the chain
*/
#ifdef TRACE_JCR_CHAIN
-void b_unlock_jcr_chain(const char *fname, int line)
+static void b_unlock_jcr_chain(const char *fname, int line)
#else
-void unlock_jcr_chain()
+static void unlock_jcr_chain()
#endif
{
- int errstat;
#ifdef TRACE_JCR_CHAIN
Dmsg3(3400, "Unlock jcr chain %d from %s:%d\n", lock_count--,
fname, line);
#endif
- if ((errstat=rwl_writeunlock(&lock)) != 0) {
- Emsg1(M_ABORT, 0, "rwl_writeunlock failure. ERR=%s\n",
- strerror(errstat));
- }
+ V(jcr_lock);
}
{
JCR *jcr;
- if (prev_jcr == NULL) {
- jcr = jobs;
- } else {
- jcr = prev_jcr->next;
- }
+ lock_jcr_chain();
+ jcr = (JCR *)jcrs->next(prev_jcr);
if (jcr) {
- P(jcr->mutex);
- jcr->use_count++;
- V(jcr->mutex);
+ jcr->inc_use_count();
Dmsg2(3400, "Inc get_next_jcr 0x%x use_count=%d\n", jcr, jcr->use_count);
}
+ unlock_jcr_chain();
return jcr;
}
/* Walk through all JCRs checking if any one is
* blocked for more than specified max time.
*/
- lock_jcr_chain();
foreach_jcr(jcr) {
- free_locked_jcr(jcr); /* OK to free now cuz chain is locked */
if (jcr->JobId == 0) {
+ free_jcr(jcr);
continue;
}
fd = jcr->store_bsock;
pthread_kill(jcr->my_thread_id, TIMEOUT_SIGNAL);
}
}
-
+ free_jcr(jcr);
}
- unlock_jcr_chain();
Dmsg0(3400, "Finished JCR timeout checks\n");
}
projects / bacula / bacula / blobdiff