struct list_head hr_all_item;
unsigned hr_unclean_stop:1,
+ hr_aborted_start:1,
hr_item_pinned:1,
hr_item_dropped:1;
* a more complete api that doesn't lead to this sort of fragility. */
atomic_t hr_steady_iterations;
+ /* terminate o2hb thread if it does not reach steady state
+ * (hr_steady_iterations == 0) within hr_unsteady_iterations */
+ atomic_t hr_unsteady_iterations;
+
char hr_dev_name[BDEVNAME_SIZE];
unsigned int hr_timeout_ms;
static void o2hb_arm_write_timeout(struct o2hb_region *reg)
{
+ /* Arm writeout only after thread reaches steady state */
+ if (atomic_read(®->hr_steady_iterations) != 0)
+ return;
+
mlog(ML_HEARTBEAT, "Queue write timeout for %u ms\n",
O2HB_MAX_WRITE_TIMEOUT_MS);
return read == computed;
}
-/* We want to make sure that nobody is heartbeating on top of us --
- * this will help detect an invalid configuration. */
-static void o2hb_check_last_timestamp(struct o2hb_region *reg)
+/*
+ * Compare the slot data with what we wrote in the last iteration.
+ * If the match fails, print an appropriate error message. This is to
+ * detect errors like... another node hearting on the same slot,
+ * flaky device that is losing writes, etc.
+ * Returns 1 if check succeeds, 0 otherwise.
+ */
+static int o2hb_check_own_slot(struct o2hb_region *reg)
{
struct o2hb_disk_slot *slot;
struct o2hb_disk_heartbeat_block *hb_block;
slot = ®->hr_slots[o2nm_this_node()];
/* Don't check on our 1st timestamp */
if (!slot->ds_last_time)
- return;
+ return 0;
hb_block = slot->ds_raw_block;
if (le64_to_cpu(hb_block->hb_seq) == slot->ds_last_time &&
le64_to_cpu(hb_block->hb_generation) == slot->ds_last_generation &&
hb_block->hb_node == slot->ds_node_num)
- return;
+ return 1;
#define ERRSTR1 "Another node is heartbeating on device"
#define ERRSTR2 "Heartbeat generation mismatch on device"
(unsigned long long)slot->ds_last_time, hb_block->hb_node,
(unsigned long long)le64_to_cpu(hb_block->hb_generation),
(unsigned long long)le64_to_cpu(hb_block->hb_seq));
+
+ return 0;
}
static inline void o2hb_prepare_block(struct o2hb_region *reg,
o2nm_node_put(node);
}
-static void o2hb_set_quorum_device(struct o2hb_region *reg,
- struct o2hb_disk_slot *slot)
+static void o2hb_set_quorum_device(struct o2hb_region *reg)
{
- assert_spin_locked(&o2hb_live_lock);
-
if (!o2hb_global_heartbeat_active())
return;
- if (test_bit(reg->hr_region_num, o2hb_quorum_region_bitmap))
+ /* Prevent race with o2hb_heartbeat_group_drop_item() */
+ if (kthread_should_stop())
+ return;
+
+ /* Tag region as quorum only after thread reaches steady state */
+ if (atomic_read(®->hr_steady_iterations) != 0)
return;
+ spin_lock(&o2hb_live_lock);
+
+ if (test_bit(reg->hr_region_num, o2hb_quorum_region_bitmap))
+ goto unlock;
+
/*
* A region can be added to the quorum only when it sees all
* live nodes heartbeat on it. In other words, the region has been
*/
if (memcmp(reg->hr_live_node_bitmap, o2hb_live_node_bitmap,
sizeof(o2hb_live_node_bitmap)))
- return;
-
- if (slot->ds_changed_samples < O2HB_LIVE_THRESHOLD)
- return;
+ goto unlock;
- printk(KERN_NOTICE "o2hb: Region %s is now a quorum device\n",
- config_item_name(®->hr_item));
+ printk(KERN_NOTICE "o2hb: Region %s (%s) is now a quorum device\n",
+ config_item_name(®->hr_item), reg->hr_dev_name);
set_bit(reg->hr_region_num, o2hb_quorum_region_bitmap);
if (o2hb_pop_count(&o2hb_quorum_region_bitmap,
O2NM_MAX_REGIONS) > O2HB_PIN_CUT_OFF)
o2hb_region_unpin(NULL);
+unlock:
+ spin_unlock(&o2hb_live_lock);
}
static int o2hb_check_slot(struct o2hb_region *reg,
slot->ds_equal_samples = 0;
}
out:
- o2hb_set_quorum_device(reg, slot);
-
spin_unlock(&o2hb_live_lock);
o2hb_run_event_list(&event);
static int o2hb_do_disk_heartbeat(struct o2hb_region *reg)
{
- int i, ret, highest_node, change = 0;
+ int i, ret, highest_node;
+ int membership_change = 0, own_slot_ok = 0;
unsigned long configured_nodes[BITS_TO_LONGS(O2NM_MAX_NODES)];
unsigned long live_node_bitmap[BITS_TO_LONGS(O2NM_MAX_NODES)];
struct o2hb_bio_wait_ctxt write_wc;
sizeof(configured_nodes));
if (ret) {
mlog_errno(ret);
- return ret;
+ goto bail;
}
/*
highest_node = o2hb_highest_node(configured_nodes, O2NM_MAX_NODES);
if (highest_node >= O2NM_MAX_NODES) {
- mlog(ML_NOTICE, "ocfs2_heartbeat: no configured nodes found!\n");
- return -EINVAL;
+ mlog(ML_NOTICE, "o2hb: No configured nodes found!\n");
+ ret = -EINVAL;
+ goto bail;
}
/* No sense in reading the slots of nodes that don't exist
ret = o2hb_read_slots(reg, highest_node + 1);
if (ret < 0) {
mlog_errno(ret);
- return ret;
+ goto bail;
}
/* With an up to date view of the slots, we can check that no
* other node has been improperly configured to heartbeat in
* our slot. */
- o2hb_check_last_timestamp(reg);
+ own_slot_ok = o2hb_check_own_slot(reg);
/* fill in the proper info for our next heartbeat */
o2hb_prepare_block(reg, reg->hr_generation);
- /* And fire off the write. Note that we don't wait on this I/O
- * until later. */
ret = o2hb_issue_node_write(reg, &write_wc);
if (ret < 0) {
mlog_errno(ret);
- return ret;
+ goto bail;
}
i = -1;
while((i = find_next_bit(configured_nodes,
O2NM_MAX_NODES, i + 1)) < O2NM_MAX_NODES) {
- change |= o2hb_check_slot(reg, ®->hr_slots[i]);
+ membership_change |= o2hb_check_slot(reg, ®->hr_slots[i]);
}
/*
* disk */
mlog(ML_ERROR, "Write error %d on device \"%s\"\n",
write_wc.wc_error, reg->hr_dev_name);
- return write_wc.wc_error;
+ ret = write_wc.wc_error;
+ goto bail;
}
- o2hb_arm_write_timeout(reg);
+ /* Skip disarming the timeout if own slot has stale/bad data */
+ if (own_slot_ok) {
+ o2hb_set_quorum_device(reg);
+ o2hb_arm_write_timeout(reg);
+ }
+bail:
/* let the person who launched us know when things are steady */
- if (!change && (atomic_read(®->hr_steady_iterations) != 0)) {
- if (atomic_dec_and_test(®->hr_steady_iterations))
+ if (atomic_read(®->hr_steady_iterations) != 0) {
+ if (!ret && own_slot_ok && !membership_change) {
+ if (atomic_dec_and_test(®->hr_steady_iterations))
+ wake_up(&o2hb_steady_queue);
+ }
+ }
+
+ if (atomic_read(®->hr_steady_iterations) != 0) {
+ if (atomic_dec_and_test(®->hr_unsteady_iterations)) {
+ printk(KERN_NOTICE "o2hb: Unable to stabilize "
+ "heartbeart on region %s (%s)\n",
+ config_item_name(®->hr_item),
+ reg->hr_dev_name);
+ atomic_set(®->hr_steady_iterations, 0);
+ reg->hr_aborted_start = 1;
wake_up(&o2hb_steady_queue);
+ ret = -EIO;
+ }
}
- return 0;
+ return ret;
}
/* Subtract b from a, storing the result in a. a *must* have a larger
/* Pin node */
o2nm_depend_this_node();
- while (!kthread_should_stop() && !reg->hr_unclean_stop) {
+ while (!kthread_should_stop() &&
+ !reg->hr_unclean_stop && !reg->hr_aborted_start) {
/* We track the time spent inside
* o2hb_do_disk_heartbeat so that we avoid more than
* hr_timeout_ms between disk writes. On busy systems
* likely to time itself out. */
do_gettimeofday(&before_hb);
- i = 0;
- do {
- ret = o2hb_do_disk_heartbeat(reg);
- } while (ret && ++i < 2);
+ ret = o2hb_do_disk_heartbeat(reg);
do_gettimeofday(&after_hb);
elapsed_msec = o2hb_elapsed_msecs(&before_hb, &after_hb);
after_hb.tv_sec, (unsigned long) after_hb.tv_usec,
elapsed_msec);
- if (elapsed_msec < reg->hr_timeout_ms) {
+ if (!kthread_should_stop() &&
+ elapsed_msec < reg->hr_timeout_ms) {
/* the kthread api has blocked signals for us so no
* need to record the return value. */
msleep_interruptible(reg->hr_timeout_ms - elapsed_msec);
* to timeout on this region when we could just as easily
* write a clear generation - thus indicating to them that
* this node has left this region.
- *
- * XXX: Should we skip this on unclean_stop? */
- o2hb_prepare_block(reg, 0);
- ret = o2hb_issue_node_write(reg, &write_wc);
- if (ret == 0) {
- o2hb_wait_on_io(reg, &write_wc);
- } else {
- mlog_errno(ret);
+ */
+ if (!reg->hr_unclean_stop && !reg->hr_aborted_start) {
+ o2hb_prepare_block(reg, 0);
+ ret = o2hb_issue_node_write(reg, &write_wc);
+ if (ret == 0)
+ o2hb_wait_on_io(reg, &write_wc);
+ else
+ mlog_errno(ret);
}
/* Unpin node */
o2nm_undepend_this_node();
- mlog(ML_HEARTBEAT|ML_KTHREAD, "hb thread exiting\n");
+ mlog(ML_HEARTBEAT|ML_KTHREAD, "o2hb thread exiting\n");
return 0;
}
struct o2hb_debug_buf *db = inode->i_private;
struct o2hb_region *reg;
unsigned long map[BITS_TO_LONGS(O2NM_MAX_NODES)];
+ unsigned long lts;
char *buf = NULL;
int i = -1;
int out = 0;
case O2HB_DB_TYPE_REGION_ELAPSED_TIME:
reg = (struct o2hb_region *)db->db_data;
- out += snprintf(buf + out, PAGE_SIZE - out, "%u\n",
- jiffies_to_msecs(jiffies -
- reg->hr_last_timeout_start));
+ lts = reg->hr_last_timeout_start;
+ /* If 0, it has never been set before */
+ if (lts)
+ lts = jiffies_to_msecs(jiffies - lts);
+ out += snprintf(buf + out, PAGE_SIZE - out, "%lu\n", lts);
goto done;
case O2HB_DB_TYPE_REGION_PINNED:
struct page *page;
struct o2hb_region *reg = to_o2hb_region(item);
+ mlog(ML_HEARTBEAT, "hb region release (%s)\n", reg->hr_dev_name);
+
if (reg->hr_tmp_block)
kfree(reg->hr_tmp_block);
live_threshold <<= 1;
spin_unlock(&o2hb_live_lock);
}
- atomic_set(®->hr_steady_iterations, live_threshold + 1);
+ ++live_threshold;
+ atomic_set(®->hr_steady_iterations, live_threshold);
+ /* unsteady_iterations is double the steady_iterations */
+ atomic_set(®->hr_unsteady_iterations, (live_threshold << 1));
hb_task = kthread_run(o2hb_thread, reg, "o2hb-%s",
reg->hr_item.ci_name);
ret = wait_event_interruptible(o2hb_steady_queue,
atomic_read(®->hr_steady_iterations) == 0);
if (ret) {
- /* We got interrupted (hello ptrace!). Clean up */
- spin_lock(&o2hb_live_lock);
- hb_task = reg->hr_task;
- reg->hr_task = NULL;
- spin_unlock(&o2hb_live_lock);
+ atomic_set(®->hr_steady_iterations, 0);
+ reg->hr_aborted_start = 1;
+ }
- if (hb_task)
- kthread_stop(hb_task);
+ if (reg->hr_aborted_start) {
+ ret = -EIO;
goto out;
}
ret = -EIO;
if (hb_task && o2hb_global_heartbeat_active())
- printk(KERN_NOTICE "o2hb: Heartbeat started on region %s\n",
- config_item_name(®->hr_item));
+ printk(KERN_NOTICE "o2hb: Heartbeat started on region %s (%s)\n",
+ config_item_name(®->hr_item), reg->hr_dev_name);
out:
if (filp)
/* stop the thread when the user removes the region dir */
spin_lock(&o2hb_live_lock);
- if (o2hb_global_heartbeat_active()) {
- clear_bit(reg->hr_region_num, o2hb_region_bitmap);
- clear_bit(reg->hr_region_num, o2hb_live_region_bitmap);
- if (test_bit(reg->hr_region_num, o2hb_quorum_region_bitmap))
- quorum_region = 1;
- clear_bit(reg->hr_region_num, o2hb_quorum_region_bitmap);
- }
hb_task = reg->hr_task;
reg->hr_task = NULL;
reg->hr_item_dropped = 1;
if (hb_task)
kthread_stop(hb_task);
+ if (o2hb_global_heartbeat_active()) {
+ spin_lock(&o2hb_live_lock);
+ clear_bit(reg->hr_region_num, o2hb_region_bitmap);
+ clear_bit(reg->hr_region_num, o2hb_live_region_bitmap);
+ if (test_bit(reg->hr_region_num, o2hb_quorum_region_bitmap))
+ quorum_region = 1;
+ clear_bit(reg->hr_region_num, o2hb_quorum_region_bitmap);
+ spin_unlock(&o2hb_live_lock);
+ printk(KERN_NOTICE "o2hb: Heartbeat %s on region %s (%s)\n",
+ ((atomic_read(®->hr_steady_iterations) == 0) ?
+ "stopped" : "start aborted"), config_item_name(item),
+ reg->hr_dev_name);
+ }
+
/*
* If we're racing a dev_write(), we need to wake them. They will
* check reg->hr_task
*/
if (atomic_read(®->hr_steady_iterations) != 0) {
+ reg->hr_aborted_start = 1;
atomic_set(®->hr_steady_iterations, 0);
wake_up(&o2hb_steady_queue);
}
- if (o2hb_global_heartbeat_active())
- printk(KERN_NOTICE "o2hb: Heartbeat stopped on region %s\n",
- config_item_name(®->hr_item));
-
config_item_put(item);
if (!o2hb_global_heartbeat_active() || !quorum_region)
git.openpandora.org / pandora-kernel.git / blobdiff