#include <linux/random.h>
#include <linux/crc32.h>
#include <linux/time.h>
+#include <linux/debugfs.h>
#include "heartbeat.h"
#include "tcp.h"
static LIST_HEAD(o2hb_node_events);
static DECLARE_WAIT_QUEUE_HEAD(o2hb_steady_queue);
+#define O2HB_DEBUG_DIR "o2hb"
+#define O2HB_DEBUG_LIVENODES "livenodes"
+static struct dentry *o2hb_debug_dir;
+static struct dentry *o2hb_debug_livenodes;
+
static LIST_HEAD(o2hb_all_regions);
static struct o2hb_callback {
static void o2hb_arm_write_timeout(struct o2hb_region *reg)
{
- mlog(0, "Queue write timeout for %u ms\n", O2HB_MAX_WRITE_TIMEOUT_MS);
+ mlog(ML_HEARTBEAT, "Queue write timeout for %u ms\n",
+ O2HB_MAX_WRITE_TIMEOUT_MS);
cancel_delayed_work(®->hr_write_timeout_work);
reg->hr_last_timeout_start = jiffies;
flush_scheduled_work();
}
-static inline void o2hb_bio_wait_init(struct o2hb_bio_wait_ctxt *wc,
- unsigned int num_ios)
+static inline void o2hb_bio_wait_init(struct o2hb_bio_wait_ctxt *wc)
{
- atomic_set(&wc->wc_num_reqs, num_ios);
+ atomic_set(&wc->wc_num_reqs, 1);
init_completion(&wc->wc_io_complete);
wc->wc_error = 0;
}
struct address_space *mapping = reg->hr_bdev->bd_inode->i_mapping;
blk_run_address_space(mapping);
+ o2hb_bio_wait_dec(wc, 1);
wait_for_completion(&wc->wc_io_complete);
}
-static int o2hb_bio_end_io(struct bio *bio,
- unsigned int bytes_done,
+static void o2hb_bio_end_io(struct bio *bio,
int error)
{
struct o2hb_bio_wait_ctxt *wc = bio->bi_private;
wc->wc_error = error;
}
- if (bio->bi_size)
- return 1;
-
o2hb_bio_wait_dec(wc, 1);
- return 0;
+ bio_put(bio);
}
/* Setup a Bio to cover I/O against num_slots slots starting at
* start_slot. */
static struct bio *o2hb_setup_one_bio(struct o2hb_region *reg,
struct o2hb_bio_wait_ctxt *wc,
- unsigned int start_slot,
- unsigned int num_slots)
+ unsigned int *current_slot,
+ unsigned int max_slots)
{
- int i, nr_vecs, len, first_page, last_page;
+ int len, current_page;
unsigned int vec_len, vec_start;
unsigned int bits = reg->hr_block_bits;
unsigned int spp = reg->hr_slots_per_page;
+ unsigned int cs = *current_slot;
struct bio *bio;
struct page *page;
- nr_vecs = (num_slots + spp - 1) / spp;
-
/* Testing has shown this allocation to take long enough under
* GFP_KERNEL that the local node can get fenced. It would be
* nicest if we could pre-allocate these bios and avoid this
* all together. */
- bio = bio_alloc(GFP_ATOMIC, nr_vecs);
+ bio = bio_alloc(GFP_ATOMIC, 16);
if (!bio) {
mlog(ML_ERROR, "Could not alloc slots BIO!\n");
bio = ERR_PTR(-ENOMEM);
}
/* Must put everything in 512 byte sectors for the bio... */
- bio->bi_sector = (reg->hr_start_block + start_slot) << (bits - 9);
+ bio->bi_sector = (reg->hr_start_block + cs) << (bits - 9);
bio->bi_bdev = reg->hr_bdev;
bio->bi_private = wc;
bio->bi_end_io = o2hb_bio_end_io;
- first_page = start_slot / spp;
- last_page = first_page + nr_vecs;
- vec_start = (start_slot << bits) % PAGE_CACHE_SIZE;
- for(i = first_page; i < last_page; i++) {
- page = reg->hr_slot_data[i];
+ vec_start = (cs << bits) % PAGE_CACHE_SIZE;
+ while(cs < max_slots) {
+ current_page = cs / spp;
+ page = reg->hr_slot_data[current_page];
- vec_len = PAGE_CACHE_SIZE;
- /* last page might be short */
- if (((i + 1) * spp) > (start_slot + num_slots))
- vec_len = ((num_slots + start_slot) % spp) << bits;
- vec_len -= vec_start;
+ vec_len = min(PAGE_CACHE_SIZE - vec_start,
+ (max_slots-cs) * (PAGE_CACHE_SIZE/spp) );
mlog(ML_HB_BIO, "page %d, vec_len = %u, vec_start = %u\n",
- i, vec_len, vec_start);
+ current_page, vec_len, vec_start);
len = bio_add_page(bio, page, vec_len, vec_start);
- if (len != vec_len) {
- bio_put(bio);
- bio = ERR_PTR(-EIO);
-
- mlog(ML_ERROR, "Error adding page to bio i = %d, "
- "vec_len = %u, len = %d\n, start = %u\n",
- i, vec_len, len, vec_start);
- goto bail;
- }
+ if (len != vec_len) break;
+ cs += vec_len / (PAGE_CACHE_SIZE/spp);
vec_start = 0;
}
bail:
+ *current_slot = cs;
return bio;
}
-/*
- * Compute the maximum number of sectors the bdev can handle in one bio,
- * as a power of two.
- *
- * Stolen from oracleasm, thanks Joel!
- */
-static int compute_max_sectors(struct block_device *bdev)
-{
- int max_pages, max_sectors, pow_two_sectors;
-
- struct request_queue *q;
-
- q = bdev_get_queue(bdev);
- max_pages = q->max_sectors >> (PAGE_SHIFT - 9);
- if (max_pages > BIO_MAX_PAGES)
- max_pages = BIO_MAX_PAGES;
- if (max_pages > q->max_phys_segments)
- max_pages = q->max_phys_segments;
- if (max_pages > q->max_hw_segments)
- max_pages = q->max_hw_segments;
- max_pages--; /* Handle I/Os that straddle a page */
-
- if (max_pages) {
- max_sectors = max_pages << (PAGE_SHIFT - 9);
- } else {
- /* If BIO contains 1 or less than 1 page. */
- max_sectors = q->max_sectors;
- }
- /* Why is fls() 1-based???? */
- pow_two_sectors = 1 << (fls(max_sectors) - 1);
-
- return pow_two_sectors;
-}
-
-static inline void o2hb_compute_request_limits(struct o2hb_region *reg,
- unsigned int num_slots,
- unsigned int *num_bios,
- unsigned int *slots_per_bio)
-{
- unsigned int max_sectors, io_sectors;
-
- max_sectors = compute_max_sectors(reg->hr_bdev);
-
- io_sectors = num_slots << (reg->hr_block_bits - 9);
-
- *num_bios = (io_sectors + max_sectors - 1) / max_sectors;
- *slots_per_bio = max_sectors >> (reg->hr_block_bits - 9);
-
- mlog(ML_HB_BIO, "My io size is %u sectors for %u slots. This "
- "device can handle %u sectors of I/O\n", io_sectors, num_slots,
- max_sectors);
- mlog(ML_HB_BIO, "Will need %u bios holding %u slots each\n",
- *num_bios, *slots_per_bio);
-}
-
static int o2hb_read_slots(struct o2hb_region *reg,
unsigned int max_slots)
{
- unsigned int num_bios, slots_per_bio, start_slot, num_slots;
- int i, status;
+ unsigned int current_slot=0;
+ int status;
struct o2hb_bio_wait_ctxt wc;
- struct bio **bios;
struct bio *bio;
- o2hb_compute_request_limits(reg, max_slots, &num_bios, &slots_per_bio);
+ o2hb_bio_wait_init(&wc);
- bios = kcalloc(num_bios, sizeof(struct bio *), GFP_KERNEL);
- if (!bios) {
- status = -ENOMEM;
- mlog_errno(status);
- return status;
- }
-
- o2hb_bio_wait_init(&wc, num_bios);
-
- num_slots = slots_per_bio;
- for(i = 0; i < num_bios; i++) {
- start_slot = i * slots_per_bio;
-
- /* adjust num_slots at last bio */
- if (max_slots < (start_slot + num_slots))
- num_slots = max_slots - start_slot;
-
- bio = o2hb_setup_one_bio(reg, &wc, start_slot, num_slots);
+ while(current_slot < max_slots) {
+ bio = o2hb_setup_one_bio(reg, &wc, ¤t_slot, max_slots);
if (IS_ERR(bio)) {
- o2hb_bio_wait_dec(&wc, num_bios - i);
-
status = PTR_ERR(bio);
mlog_errno(status);
goto bail_and_wait;
}
- bios[i] = bio;
+ atomic_inc(&wc.wc_num_reqs);
submit_bio(READ, bio);
}
if (wc.wc_error && !status)
status = wc.wc_error;
- if (bios) {
- for(i = 0; i < num_bios; i++)
- if (bios[i])
- bio_put(bios[i]);
- kfree(bios);
- }
-
return status;
}
static int o2hb_issue_node_write(struct o2hb_region *reg,
- struct bio **write_bio,
struct o2hb_bio_wait_ctxt *write_wc)
{
int status;
unsigned int slot;
struct bio *bio;
- o2hb_bio_wait_init(write_wc, 1);
+ o2hb_bio_wait_init(write_wc);
slot = o2nm_this_node();
- bio = o2hb_setup_one_bio(reg, write_wc, slot, 1);
+ bio = o2hb_setup_one_bio(reg, write_wc, &slot, slot+1);
if (IS_ERR(bio)) {
status = PTR_ERR(bio);
mlog_errno(status);
goto bail;
}
+ atomic_inc(&write_wc->wc_num_reqs);
submit_bio(WRITE, bio);
- *write_bio = bio;
status = 0;
bail:
return status;
hb_block));
mlog(ML_HB_BIO, "our node generation = 0x%llx, cksum = 0x%x\n",
- (long long)cpu_to_le64(generation),
+ (long long)generation,
le32_to_cpu(hb_block->hb_cksum));
}
{
int i, ret, highest_node, change = 0;
unsigned long configured_nodes[BITS_TO_LONGS(O2NM_MAX_NODES)];
- struct bio *write_bio;
struct o2hb_bio_wait_ctxt write_wc;
ret = o2nm_configured_node_map(configured_nodes,
/* And fire off the write. Note that we don't wait on this I/O
* until later. */
- ret = o2hb_issue_node_write(reg, &write_bio, &write_wc);
+ ret = o2hb_issue_node_write(reg, &write_wc);
if (ret < 0) {
mlog_errno(ret);
return ret;
* people we find in our steady state have seen us.
*/
o2hb_wait_on_io(reg, &write_wc);
- bio_put(write_bio);
if (write_wc.wc_error) {
/* Do not re-arm the write timeout on I/O error - we
* can't be sure that the new block ever made it to
{
int i, ret;
struct o2hb_region *reg = data;
- struct bio *write_bio;
struct o2hb_bio_wait_ctxt write_wc;
struct timeval before_hb, after_hb;
unsigned int elapsed_msec;
while (!kthread_should_stop() && !reg->hr_unclean_stop) {
/* We track the time spent inside
- * o2hb_do_disk_heartbeat so that we avoid more then
+ * o2hb_do_disk_heartbeat so that we avoid more than
* hr_timeout_ms between disk writes. On busy systems
* this should result in a heartbeat which is less
* likely to time itself out. */
do_gettimeofday(&after_hb);
elapsed_msec = o2hb_elapsed_msecs(&before_hb, &after_hb);
- mlog(0, "start = %lu.%lu, end = %lu.%lu, msec = %u\n",
+ mlog(ML_HEARTBEAT,
+ "start = %lu.%lu, end = %lu.%lu, msec = %u\n",
before_hb.tv_sec, (unsigned long) before_hb.tv_usec,
after_hb.tv_sec, (unsigned long) after_hb.tv_usec,
elapsed_msec);
*
* XXX: Should we skip this on unclean_stop? */
o2hb_prepare_block(reg, 0);
- ret = o2hb_issue_node_write(reg, &write_bio, &write_wc);
+ ret = o2hb_issue_node_write(reg, &write_wc);
if (ret == 0) {
o2hb_wait_on_io(reg, &write_wc);
- bio_put(write_bio);
} else {
mlog_errno(ret);
}
return 0;
}
-void o2hb_init(void)
+#ifdef CONFIG_DEBUG_FS
+static int o2hb_debug_open(struct inode *inode, struct file *file)
+{
+ unsigned long map[BITS_TO_LONGS(O2NM_MAX_NODES)];
+ char *buf = NULL;
+ int i = -1;
+ int out = 0;
+
+ buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
+ if (!buf)
+ goto bail;
+
+ o2hb_fill_node_map(map, sizeof(map));
+
+ while ((i = find_next_bit(map, O2NM_MAX_NODES, i + 1)) < O2NM_MAX_NODES)
+ out += snprintf(buf + out, PAGE_SIZE - out, "%d ", i);
+ out += snprintf(buf + out, PAGE_SIZE - out, "\n");
+
+ i_size_write(inode, out);
+
+ file->private_data = buf;
+
+ return 0;
+bail:
+ return -ENOMEM;
+}
+
+static int o2hb_debug_release(struct inode *inode, struct file *file)
+{
+ kfree(file->private_data);
+ return 0;
+}
+
+static ssize_t o2hb_debug_read(struct file *file, char __user *buf,
+ size_t nbytes, loff_t *ppos)
+{
+ return simple_read_from_buffer(buf, nbytes, ppos, file->private_data,
+ i_size_read(file->f_mapping->host));
+}
+#else
+static int o2hb_debug_open(struct inode *inode, struct file *file)
+{
+ return 0;
+}
+static int o2hb_debug_release(struct inode *inode, struct file *file)
+{
+ return 0;
+}
+static ssize_t o2hb_debug_read(struct file *file, char __user *buf,
+ size_t nbytes, loff_t *ppos)
+{
+ return 0;
+}
+#endif /* CONFIG_DEBUG_FS */
+
+static const struct file_operations o2hb_debug_fops = {
+ .open = o2hb_debug_open,
+ .release = o2hb_debug_release,
+ .read = o2hb_debug_read,
+ .llseek = generic_file_llseek,
+};
+
+void o2hb_exit(void)
+{
+ if (o2hb_debug_livenodes)
+ debugfs_remove(o2hb_debug_livenodes);
+ if (o2hb_debug_dir)
+ debugfs_remove(o2hb_debug_dir);
+}
+
+int o2hb_init(void)
{
int i;
INIT_LIST_HEAD(&o2hb_node_events);
memset(o2hb_live_node_bitmap, 0, sizeof(o2hb_live_node_bitmap));
+
+ o2hb_debug_dir = debugfs_create_dir(O2HB_DEBUG_DIR, NULL);
+ if (!o2hb_debug_dir) {
+ mlog_errno(-ENOMEM);
+ return -ENOMEM;
+ }
+
+ o2hb_debug_livenodes = debugfs_create_file(O2HB_DEBUG_LIVENODES,
+ S_IFREG|S_IRUSR,
+ o2hb_debug_dir, NULL,
+ &o2hb_debug_fops);
+ if (!o2hb_debug_livenodes) {
+ mlog_errno(-ENOMEM);
+ debugfs_remove(o2hb_debug_dir);
+ return -ENOMEM;
+ }
+
+ return 0;
}
/* if we're already in a callback then we're already serialized by the sem */
}
if (reg->hr_bdev)
- blkdev_put(reg->hr_bdev);
+ blkdev_put(reg->hr_bdev, FMODE_READ|FMODE_WRITE);
if (reg->hr_slots)
kfree(reg->hr_slots);
const char *page,
size_t count)
{
+ struct task_struct *hb_task;
long fd;
int sectsize;
char *p = (char *)page;
goto out;
reg->hr_bdev = I_BDEV(filp->f_mapping->host);
- ret = blkdev_get(reg->hr_bdev, FMODE_WRITE | FMODE_READ, 0);
+ ret = blkdev_get(reg->hr_bdev, FMODE_WRITE | FMODE_READ);
if (ret) {
reg->hr_bdev = NULL;
goto out;
bdevname(reg->hr_bdev, reg->hr_dev_name);
- sectsize = bdev_hardsect_size(reg->hr_bdev);
+ sectsize = bdev_logical_block_size(reg->hr_bdev);
if (sectsize != reg->hr_block_bytes) {
mlog(ML_ERROR,
"blocksize %u incorrect for device, expected %d",
*/
atomic_set(®->hr_steady_iterations, O2HB_LIVE_THRESHOLD + 1);
- reg->hr_task = kthread_run(o2hb_thread, reg, "o2hb-%s",
- reg->hr_item.ci_name);
- if (IS_ERR(reg->hr_task)) {
- ret = PTR_ERR(reg->hr_task);
+ hb_task = kthread_run(o2hb_thread, reg, "o2hb-%s",
+ reg->hr_item.ci_name);
+ if (IS_ERR(hb_task)) {
+ ret = PTR_ERR(hb_task);
mlog_errno(ret);
- reg->hr_task = NULL;
goto out;
}
+ spin_lock(&o2hb_live_lock);
+ reg->hr_task = hb_task;
+ spin_unlock(&o2hb_live_lock);
+
ret = wait_event_interruptible(o2hb_steady_queue,
atomic_read(®->hr_steady_iterations) == 0);
if (ret) {
- kthread_stop(reg->hr_task);
+ /* 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);
+
+ if (hb_task)
+ kthread_stop(hb_task);
goto out;
}
- ret = count;
+ /* Ok, we were woken. Make sure it wasn't by drop_item() */
+ spin_lock(&o2hb_live_lock);
+ hb_task = reg->hr_task;
+ spin_unlock(&o2hb_live_lock);
+
+ if (hb_task)
+ ret = count;
+ else
+ ret = -EIO;
+
out:
if (filp)
fput(filp);
iput(inode);
if (ret < 0) {
if (reg->hr_bdev) {
- blkdev_put(reg->hr_bdev);
+ blkdev_put(reg->hr_bdev, FMODE_READ|FMODE_WRITE);
reg->hr_bdev = NULL;
}
}
static ssize_t o2hb_region_pid_read(struct o2hb_region *reg,
char *page)
{
- if (!reg->hr_task)
+ pid_t pid = 0;
+
+ spin_lock(&o2hb_live_lock);
+ if (reg->hr_task)
+ pid = task_pid_nr(reg->hr_task);
+ spin_unlock(&o2hb_live_lock);
+
+ if (!pid)
return 0;
- return sprintf(page, "%u\n", reg->hr_task->pid);
+ return sprintf(page, "%u\n", pid);
}
struct o2hb_region_attribute {
const char *name)
{
struct o2hb_region *reg = NULL;
- struct config_item *ret = NULL;
reg = kzalloc(sizeof(struct o2hb_region), GFP_KERNEL);
if (reg == NULL)
- goto out; /* ENOMEM */
+ return ERR_PTR(-ENOMEM);
config_item_init_type_name(®->hr_item, name, &o2hb_region_type);
- ret = ®->hr_item;
-
spin_lock(&o2hb_live_lock);
list_add_tail(®->hr_all_item, &o2hb_all_regions);
spin_unlock(&o2hb_live_lock);
-out:
- if (ret == NULL)
- kfree(reg);
- return ret;
+ return ®->hr_item;
}
static void o2hb_heartbeat_group_drop_item(struct config_group *group,
struct config_item *item)
{
+ struct task_struct *hb_task;
struct o2hb_region *reg = to_o2hb_region(item);
/* stop the thread when the user removes the region dir */
- if (reg->hr_task) {
- kthread_stop(reg->hr_task);
- reg->hr_task = NULL;
+ spin_lock(&o2hb_live_lock);
+ hb_task = reg->hr_task;
+ reg->hr_task = NULL;
+ spin_unlock(&o2hb_live_lock);
+
+ if (hb_task)
+ kthread_stop(hb_task);
+
+ /*
+ * 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) {
+ atomic_set(®->hr_steady_iterations, 0);
+ wake_up(&o2hb_steady_queue);
}
config_item_put(item);
}
EXPORT_SYMBOL_GPL(o2hb_setup_callback);
-int o2hb_register_callback(struct o2hb_callback_func *hc)
+static struct o2hb_region *o2hb_find_region(const char *region_uuid)
+{
+ struct o2hb_region *p, *reg = NULL;
+
+ assert_spin_locked(&o2hb_live_lock);
+
+ list_for_each_entry(p, &o2hb_all_regions, hr_all_item) {
+ if (!strcmp(region_uuid, config_item_name(&p->hr_item))) {
+ reg = p;
+ break;
+ }
+ }
+
+ return reg;
+}
+
+static int o2hb_region_get(const char *region_uuid)
+{
+ int ret = 0;
+ struct o2hb_region *reg;
+
+ spin_lock(&o2hb_live_lock);
+
+ reg = o2hb_find_region(region_uuid);
+ if (!reg)
+ ret = -ENOENT;
+ spin_unlock(&o2hb_live_lock);
+
+ if (ret)
+ goto out;
+
+ ret = o2nm_depend_this_node();
+ if (ret)
+ goto out;
+
+ ret = o2nm_depend_item(®->hr_item);
+ if (ret)
+ o2nm_undepend_this_node();
+
+out:
+ return ret;
+}
+
+static void o2hb_region_put(const char *region_uuid)
+{
+ struct o2hb_region *reg;
+
+ spin_lock(&o2hb_live_lock);
+
+ reg = o2hb_find_region(region_uuid);
+
+ spin_unlock(&o2hb_live_lock);
+
+ if (reg) {
+ o2nm_undepend_item(®->hr_item);
+ o2nm_undepend_this_node();
+ }
+}
+
+int o2hb_register_callback(const char *region_uuid,
+ struct o2hb_callback_func *hc)
{
struct o2hb_callback_func *tmp;
struct list_head *iter;
goto out;
}
+ if (region_uuid) {
+ ret = o2hb_region_get(region_uuid);
+ if (ret)
+ goto out;
+ }
+
down_write(&o2hb_callback_sem);
list_for_each(iter, &hbcall->list) {
}
EXPORT_SYMBOL_GPL(o2hb_register_callback);
-int o2hb_unregister_callback(struct o2hb_callback_func *hc)
+void o2hb_unregister_callback(const char *region_uuid,
+ struct o2hb_callback_func *hc)
{
BUG_ON(hc->hc_magic != O2HB_CB_MAGIC);
mlog(ML_HEARTBEAT, "on behalf of %p for funcs %p\n",
__builtin_return_address(0), hc);
+ /* XXX Can this happen _with_ a region reference? */
if (list_empty(&hc->hc_item))
- return 0;
+ return;
+
+ if (region_uuid)
+ o2hb_region_put(region_uuid);
down_write(&o2hb_callback_sem);
list_del_init(&hc->hc_item);
up_write(&o2hb_callback_sem);
-
- return 0;
}
EXPORT_SYMBOL_GPL(o2hb_unregister_callback);
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff