* Obviously, no zzz_dev() is allowed to call
* a www_device() or everything falls apart.
*
- * Concerning the routines lock_device() and block_device()
+ * Concerning the routines dev->r_lock()() and block_device()
* see the end of this module for details. In general,
* blocking a device leaves it in a state where all threads
* other than the current thread block when they attempt to
#include "bacula.h" /* pull in global headers */
#include "stored.h" /* pull in Storage Deamon headers */
+#ifdef SD_DEBUG_LOCK
+const int dbglvl = 0;
+#else
+const int dbglvl = 500;
+#endif
+
+
/* Forward referenced functions */
/*
block_device(dev, BST_DOING_ACQUIRE);
/* Unlock, but leave BLOCKED */
- dev->unlock();
+ dev->dunlock();
bstrncpy(PrevVolName, dev->VolCatInfo.VolCatName, sizeof(PrevVolName));
bstrncpy(dev->VolHdr.PrevVolumeName, PrevVolName, sizeof(dev->VolHdr.PrevVolumeName));
if (!mount_next_write_volume(dcr, 1)) {
free_block(label_blk);
dcr->block = block;
- dev->lock();
+ dev->dlock();
unblock_device(dev);
return false; /* device locked */
}
- dev->lock(); /* lock again */
+ dev->dlock(); /* lock again */
dev->VolCatInfo.VolCatJobs++; /* increment number of jobs on vol */
dir_update_volume_info(dcr, false); /* send Volume info to Director */
if (!write_block_to_dev(dcr)) {
berrno be;
Pmsg1(0, _("write_block_to_device Volume label failed. ERR=%s"),
- be.strerror(dev->dev_errno));
+ be.bstrerror(dev->dev_errno));
free_block(label_blk);
dcr->block = block;
unblock_device(dev);
if (!write_block_to_dev(dcr)) {
berrno be;
Pmsg1(0, _("write_block_to_device overflow block failed. ERR=%s"),
- be.strerror(dev->dev_errno));
+ be.bstrerror(dev->dev_errno));
unblock_device(dev);
return false; /* device locked */
}
return false;
}
- lock_device(dev);
+ dev->r_dlock();
/* Defer opening files */
if (!dev->is_tape()) {
Dmsg1(129, "open dev %s OK\n", dev->print_name());
bail_out:
- dev->unlock();
+ dev->dunlock();
return ok;
}
return true;
}
-
/*
- * When dev_blocked is set, all threads EXCEPT thread with id no_wait_id
- * must wait. The no_wait_id thread is out obtaining a new volume
- * and preparing the label.
+ * Find which JobId corresponds to the current thread
*/
-void _lock_device(const char *file, int line, DEVICE *dev)
+uint32_t get_jobid_from_tid(pthread_t tid)
{
- int stat;
- Dmsg3(500, "lock %d from %s:%d\n", dev->blocked(), file, line);
- dev->lock();
- if (dev->blocked() && !pthread_equal(dev->no_wait_id, pthread_self())) {
- dev->num_waiting++; /* indicate that I am waiting */
- while (dev->blocked()) {
- if ((stat = pthread_cond_wait(&dev->wait, &dev->m_mutex)) != 0) {
- dev->unlock();
- Emsg1(M_ABORT, 0, _("pthread_cond_wait failure. ERR=%s\n"),
- strerror(stat));
- }
+ JCR *jcr;
+ uint32_t JobId = 0;
+ foreach_jcr(jcr) {
+ if (pthread_equal(jcr->my_thread_id, tid)) {
+ JobId = (uint32_t)jcr->JobId;
+ break;
}
- dev->num_waiting--; /* no longer waiting */
}
+ endeach_jcr(jcr);
+ return JobId;
}
/*
return stat;
}
-void _unlock_device(const char *file, int line, DEVICE *dev)
+#ifdef SD_DEBUG_LOCK
+void DEVICE::_dlock(const char *file, int line)
+{
+ Dmsg4(sd_dbglvl, "dlock from %s:%d precnt=%d JobId=%u\n", file, line,
+ m_count, get_jobid_from_tid(pthread_self()));
+ /* Note, this *really* should be protected by a mutex, but
+ * since it is only debug code we don't worry too much.
+ */
+ if (m_count > 0 && pthread_equal(m_pid, pthread_self())) {
+ Dmsg5(sd_dbglvl, "Possible DEADLOCK!! lock held by JobId=%u from %s:%d m_count=%d JobId=%u\n",
+ get_jobid_from_tid(m_pid),
+ file, line, m_count, get_jobid_from_tid(pthread_self()));
+ }
+ P(m_mutex);
+ m_pid = pthread_self();
+ m_count++;
+}
+
+void DEVICE::_dunlock(const char *file, int line)
+{
+ m_count--;
+ Dmsg4(sd_dbglvl+1, "dunlock from %s:%d postcnt=%d JobId=%u\n", file, line,
+ m_count, get_jobid_from_tid(pthread_self()));
+ V(m_mutex);
+}
+
+void DEVICE::_r_dunlock(const char *file, int line)
{
- Dmsg2(500, "unlock from %s:%d\n", file, line);
- dev->unlock();
+ this->_dunlock(file, line);
+}
+
+#endif
+
+
+/*
+ * This is a recursive lock that checks if the device is blocked.
+ *
+ * When blocked is set, all threads EXCEPT thread with id no_wait_id
+ * must wait. The no_wait_id thread is out obtaining a new volume
+ * and preparing the label.
+ */
+#ifdef SD_DEBUG_LOCK
+void DEVICE::_r_dlock(const char *file, int line)
+#else
+void DEVICE::r_dlock()
+#endif
+{
+ int stat;
+#ifdef SD_DEBUG_LOCK
+ Dmsg4(sd_dbglvl+1, "r_dlock blked=%s from %s:%d JobId=%u\n", this->print_blocked(),
+ file, line, get_jobid_from_tid(pthread_self()));
+#else
+ Dmsg1(sd_dbglvl, "reclock blked=%s\n", this->print_blocked());
+#endif
+ this->dlock();
+ if (this->blocked() && !pthread_equal(this->no_wait_id, pthread_self())) {
+ this->num_waiting++; /* indicate that I am waiting */
+ while (this->blocked()) {
+ Dmsg3(sd_dbglvl, "r_dlock blked=%s no_wait=%p me=%p\n", this->print_blocked(),
+ this->no_wait_id, pthread_self());
+ if ((stat = pthread_cond_wait(&this->wait, &m_mutex)) != 0) {
+ berrno be;
+ this->dunlock();
+ Emsg1(M_ABORT, 0, _("pthread_cond_wait failure. ERR=%s\n"),
+ be.bstrerror(stat));
+ }
+ }
+ this->num_waiting--; /* no longer waiting */
+ }
}
/*
* Block all other threads from using the device
* Device must already be locked. After this call,
- * the device is blocked to any thread calling lock_device(),
+ * the device is blocked to any thread calling dev->r_lock(),
* but the device is not locked (i.e. no P on device). Also,
- * the current thread can do slip through the lock_device()
+ * the current thread can do slip through the dev->r_lock()
* calls without blocking.
*/
void _block_device(const char *file, int line, DEVICE *dev, int state)
{
- Dmsg3(500, "block set %d from %s:%d\n", state, file, line);
ASSERT(dev->blocked() == BST_NOT_BLOCKED);
dev->set_blocked(state); /* make other threads wait */
dev->no_wait_id = pthread_self(); /* allow us to continue */
+ Dmsg3(sd_dbglvl, "set blocked=%s from %s:%d\n", dev->print_blocked(), file, line);
}
/*
* Unblock the device, and wake up anyone who went to sleep.
+ * Enter: device locked
+ * Exit: device locked
*/
void _unblock_device(const char *file, int line, DEVICE *dev)
{
- Dmsg3(500, "unblock %s from %s:%d\n", dev->print_blocked(), file, line);
+ Dmsg3(sd_dbglvl, "unblock %s from %s:%d\n", dev->print_blocked(), file, line);
ASSERT(dev->blocked());
dev->set_blocked(BST_NOT_BLOCKED);
dev->no_wait_id = 0;
void _steal_device_lock(const char *file, int line, DEVICE *dev, bsteal_lock_t *hold, int state)
{
- Dmsg3(400, "steal lock. old=%s from %s:%d\n", dev->print_blocked(),
+ Dmsg3(sd_dbglvl, "steal lock. old=%s from %s:%d\n", dev->print_blocked(),
file, line);
hold->dev_blocked = dev->blocked();
hold->dev_prev_blocked = dev->dev_prev_blocked;
hold->no_wait_id = dev->no_wait_id;
dev->set_blocked(state);
- Dmsg1(400, "steal lock. new=%s\n", dev->print_blocked());
+ Dmsg1(sd_dbglvl, "steal lock. new=%s\n", dev->print_blocked());
dev->no_wait_id = pthread_self();
- dev->unlock();
+ dev->dunlock();
}
/*
*/
void _give_back_device_lock(const char *file, int line, DEVICE *dev, bsteal_lock_t *hold)
{
- Dmsg3(400, "return lock. old=%s from %s:%d\n",
+ Dmsg3(sd_dbglvl, "return lock. old=%s from %s:%d\n",
dev->print_blocked(), file, line);
- dev->lock();
+ dev->dlock();
dev->set_blocked(hold->dev_blocked);
dev->dev_prev_blocked = hold->dev_prev_blocked;
dev->no_wait_id = hold->no_wait_id;
- Dmsg1(400, "return lock. new=%s\n", dev->print_blocked());
+ Dmsg1(sd_dbglvl, "return lock. new=%s\n", dev->print_blocked());
if (dev->num_waiting > 0) {
pthread_cond_broadcast(&dev->wait); /* wake them up */
}
projects / bacula / bacula / blobdiff