Btrfs: Replace the transaction work queue with kthreads

This creates one kthread for commits and one kthread for
deleting old snapshots.  All the work queues are removed.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
This commit is contained in:
Chris Mason 2008-06-25 16:01:31 -04:00
parent 89ce8a63d0
commit a74a4b97b6
8 changed files with 136 additions and 118 deletions

View File

@ -1352,6 +1352,8 @@ int btrfs_search_slot(struct btrfs_trans_handle *trans, struct btrfs_root
free_extent_buffer(tmp);
goto again;
} else {
if (tmp)
free_extent_buffer(tmp);
b = read_node_slot(root, b, slot);
}
}
@ -3048,7 +3050,8 @@ int btrfs_next_leaf(struct btrfs_root *root, struct btrfs_path *path)
free_extent_buffer(c);
path->nodes[level] = next;
path->slots[level] = 0;
path->locks[level] = 1;
if (!path->skip_locking)
path->locks[level] = 1;
if (!level)
break;
if (level == 1 && path->locks[1] && path->reada)

View File

@ -23,7 +23,6 @@
#include <linux/mm.h>
#include <linux/highmem.h>
#include <linux/fs.h>
#include <linux/workqueue.h>
#include <linux/completion.h>
#include <linux/backing-dev.h>
#include <asm/kmap_types.h>
@ -519,15 +518,14 @@ struct btrfs_fs_info {
struct backing_dev_info bdi;
spinlock_t hash_lock;
struct mutex trans_mutex;
struct mutex transaction_kthread_mutex;
struct mutex cleaner_mutex;
struct mutex alloc_mutex;
struct mutex chunk_mutex;
struct mutex drop_mutex;
struct list_head trans_list;
struct list_head hashers;
struct list_head dead_roots;
struct list_head end_io_work_list;
struct work_struct end_io_work;
spinlock_t end_io_work_lock;
atomic_t nr_async_submits;
/*
@ -543,13 +541,10 @@ struct btrfs_fs_info {
struct btrfs_workers workers;
struct btrfs_workers endio_workers;
struct btrfs_workers submit_workers;
struct task_struct *transaction_kthread;
struct task_struct *cleaner_kthread;
int thread_pool_size;
#if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,18)
struct work_struct trans_work;
#else
struct delayed_work trans_work;
#endif
struct kobject super_kobj;
struct completion kobj_unregister;
int do_barriers;

View File

@ -16,6 +16,7 @@
* Boston, MA 021110-1307, USA.
*/
#include <linux/version.h>
#include <linux/fs.h>
#include <linux/blkdev.h>
#include <linux/scatterlist.h>
@ -24,6 +25,12 @@
#include <linux/writeback.h>
#include <linux/buffer_head.h> // for block_sync_page
#include <linux/workqueue.h>
#include <linux/kthread.h>
#if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,20)
# include <linux/freezer.h>
#else
# include <linux/sched.h>
#endif
#include "crc32c.h"
#include "ctree.h"
#include "disk-io.h"
@ -1100,6 +1107,87 @@ static void end_workqueue_fn(struct btrfs_work *work)
#endif
}
static int cleaner_kthread(void *arg)
{
struct btrfs_root *root = arg;
do {
smp_mb();
if (root->fs_info->closing)
break;
vfs_check_frozen(root->fs_info->sb, SB_FREEZE_WRITE);
mutex_lock(&root->fs_info->cleaner_mutex);
printk("cleaner awake\n");
btrfs_clean_old_snapshots(root);
printk("cleaner done\n");
mutex_unlock(&root->fs_info->cleaner_mutex);
if (freezing(current)) {
refrigerator();
} else {
smp_mb();
if (root->fs_info->closing)
break;
set_current_state(TASK_INTERRUPTIBLE);
schedule();
__set_current_state(TASK_RUNNING);
}
} while (!kthread_should_stop());
return 0;
}
static int transaction_kthread(void *arg)
{
struct btrfs_root *root = arg;
struct btrfs_trans_handle *trans;
struct btrfs_transaction *cur;
unsigned long now;
unsigned long delay;
int ret;
do {
smp_mb();
if (root->fs_info->closing)
break;
delay = HZ * 30;
vfs_check_frozen(root->fs_info->sb, SB_FREEZE_WRITE);
mutex_lock(&root->fs_info->transaction_kthread_mutex);
mutex_lock(&root->fs_info->trans_mutex);
cur = root->fs_info->running_transaction;
if (!cur) {
mutex_unlock(&root->fs_info->trans_mutex);
goto sleep;
}
now = get_seconds();
if (now < cur->start_time || now - cur->start_time < 30) {
mutex_unlock(&root->fs_info->trans_mutex);
delay = HZ * 5;
goto sleep;
}
mutex_unlock(&root->fs_info->trans_mutex);
btrfs_defrag_dirty_roots(root->fs_info);
trans = btrfs_start_transaction(root, 1);
ret = btrfs_commit_transaction(trans, root);
sleep:
wake_up_process(root->fs_info->cleaner_kthread);
mutex_unlock(&root->fs_info->transaction_kthread_mutex);
if (freezing(current)) {
refrigerator();
} else {
if (root->fs_info->closing)
break;
set_current_state(TASK_INTERRUPTIBLE);
schedule_timeout(delay);
__set_current_state(TASK_RUNNING);
}
} while (!kthread_should_stop());
return 0;
}
struct btrfs_root *open_ctree(struct super_block *sb,
struct btrfs_fs_devices *fs_devices,
char *options)
@ -1189,11 +1277,6 @@ struct btrfs_root *open_ctree(struct super_block *sb,
fs_info->btree_inode->i_mapping, GFP_NOFS);
fs_info->do_barriers = 1;
#if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,18)
INIT_WORK(&fs_info->trans_work, btrfs_transaction_cleaner, fs_info);
#else
INIT_DELAYED_WORK(&fs_info->trans_work, btrfs_transaction_cleaner);
#endif
BTRFS_I(fs_info->btree_inode)->root = tree_root;
memset(&BTRFS_I(fs_info->btree_inode)->location, 0,
sizeof(struct btrfs_key));
@ -1204,6 +1287,8 @@ struct btrfs_root *open_ctree(struct super_block *sb,
mutex_init(&fs_info->drop_mutex);
mutex_init(&fs_info->alloc_mutex);
mutex_init(&fs_info->chunk_mutex);
mutex_init(&fs_info->transaction_kthread_mutex);
mutex_init(&fs_info->cleaner_mutex);
#if 0
ret = add_hasher(fs_info, "crc32c");
@ -1247,7 +1332,6 @@ struct btrfs_root *open_ctree(struct super_block *sb,
btrfs_start_workers(&fs_info->submit_workers, 1);
btrfs_start_workers(&fs_info->endio_workers, fs_info->thread_pool_size);
err = -EINVAL;
if (btrfs_super_num_devices(disk_super) > fs_devices->open_devices) {
printk("Btrfs: wanted %llu devices, but found %llu\n",
@ -1341,9 +1425,22 @@ struct btrfs_root *open_ctree(struct super_block *sb,
fs_info->data_alloc_profile = (u64)-1;
fs_info->metadata_alloc_profile = (u64)-1;
fs_info->system_alloc_profile = fs_info->metadata_alloc_profile;
fs_info->cleaner_kthread = kthread_run(cleaner_kthread, tree_root,
"btrfs-cleaner");
if (!fs_info->cleaner_kthread)
goto fail_extent_root;
fs_info->transaction_kthread = kthread_run(transaction_kthread,
tree_root,
"btrfs-transaction");
if (!fs_info->transaction_kthread)
goto fail_trans_kthread;
return tree_root;
fail_trans_kthread:
kthread_stop(fs_info->cleaner_kthread);
fail_extent_root:
free_extent_buffer(extent_root->node);
fail_tree_root:
@ -1562,8 +1659,11 @@ int close_ctree(struct btrfs_root *root)
fs_info->closing = 1;
smp_mb();
btrfs_transaction_flush_work(root);
kthread_stop(root->fs_info->transaction_kthread);
kthread_stop(root->fs_info->cleaner_kthread);
btrfs_defrag_dirty_roots(root->fs_info);
btrfs_clean_old_snapshots(root);
trans = btrfs_start_transaction(root, 1);
ret = btrfs_commit_transaction(trans, root);
/* run commit again to drop the original snapshot */
@ -1574,8 +1674,6 @@ int close_ctree(struct btrfs_root *root)
write_ctree_super(NULL, root);
btrfs_transaction_flush_work(root);
if (fs_info->delalloc_bytes) {
printk("btrfs: at unmount delalloc count %Lu\n",
fs_info->delalloc_bytes);

View File

@ -1216,15 +1216,16 @@ static int do_chunk_alloc(struct btrfs_trans_handle *trans,
if (ret == -ENOSPC) {
printk("space info full %Lu\n", flags);
space_info->full = 1;
goto out;
goto out_unlock;
}
BUG_ON(ret);
ret = btrfs_make_block_group(trans, extent_root, 0, flags,
BTRFS_FIRST_CHUNK_TREE_OBJECTID, start, num_bytes);
BUG_ON(ret);
out:
out_unlock:
mutex_unlock(&extent_root->fs_info->chunk_mutex);
out:
return 0;
}
@ -2274,7 +2275,8 @@ static int noinline walk_down_tree(struct btrfs_trans_handle *trans,
free_extent_buffer(next);
mutex_unlock(&root->fs_info->alloc_mutex);
reada_walk_down(root, cur, path->slots[*level]);
if (path->slots[*level] == 0)
reada_walk_down(root, cur, path->slots[*level]);
next = read_tree_block(root, bytenr, blocksize,
ptr_gen);
@ -2446,8 +2448,6 @@ int btrfs_drop_snapshot(struct btrfs_trans_handle *trans, struct btrfs_root
break;
if (wret < 0)
ret = wret;
ret = -EAGAIN;
break;
}
for (i = 0; i <= orig_level; i++) {
if (path->nodes[i]) {

View File

@ -340,7 +340,6 @@ static int btrfs_fill_super(struct super_block * sb,
goto fail_close;
sb->s_root = root_dentry;
btrfs_transaction_queue_work(tree_root, HZ * 30);
#if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,25)
save_mount_options(sb, data);
@ -416,9 +415,7 @@ static int btrfs_get_sb(struct file_system_type *fs_type, int flags,
goto error_free_subvol_name;
bdev = fs_devices->latest_bdev;
btrfs_lock_volumes();
s = sget(fs_type, btrfs_test_super, set_anon_super, fs_devices);
btrfs_unlock_volumes();
if (IS_ERR(s))
goto error_s;
@ -530,13 +527,15 @@ static long btrfs_control_ioctl(struct file *file, unsigned int cmd,
static void btrfs_write_super_lockfs(struct super_block *sb)
{
struct btrfs_root *root = btrfs_sb(sb);
btrfs_transaction_flush_work(root);
mutex_lock(&root->fs_info->transaction_kthread_mutex);
mutex_lock(&root->fs_info->cleaner_mutex);
}
static void btrfs_unlockfs(struct super_block *sb)
{
struct btrfs_root *root = btrfs_sb(sb);
btrfs_transaction_queue_work(root, HZ * 30);
mutex_unlock(&root->fs_info->cleaner_mutex);
mutex_unlock(&root->fs_info->transaction_kthread_mutex);
}
static struct super_operations btrfs_super_ops = {
@ -589,10 +588,9 @@ static int __init init_btrfs_fs(void)
if (err)
return err;
btrfs_init_transaction_sys();
err = btrfs_init_cachep();
if (err)
goto free_transaction_sys;
goto free_sysfs;
err = extent_io_init();
if (err)
@ -618,15 +616,13 @@ static int __init init_btrfs_fs(void)
extent_io_exit();
free_cachep:
btrfs_destroy_cachep();
free_transaction_sys:
btrfs_exit_transaction_sys();
free_sysfs:
btrfs_exit_sysfs();
return err;
}
static void __exit exit_btrfs_fs(void)
{
btrfs_exit_transaction_sys();
btrfs_destroy_cachep();
extent_map_exit();
extent_io_exit();

View File

@ -29,8 +29,6 @@ static int total_trans = 0;
extern struct kmem_cache *btrfs_trans_handle_cachep;
extern struct kmem_cache *btrfs_transaction_cachep;
static struct workqueue_struct *trans_wq;
#define BTRFS_ROOT_TRANS_TAG 0
#define BTRFS_ROOT_DEFRAG_TAG 1
@ -807,81 +805,15 @@ int btrfs_clean_old_snapshots(struct btrfs_root *root)
{
struct list_head dirty_roots;
INIT_LIST_HEAD(&dirty_roots);
again:
mutex_lock(&root->fs_info->trans_mutex);
list_splice_init(&root->fs_info->dead_roots, &dirty_roots);
mutex_unlock(&root->fs_info->trans_mutex);
if (!list_empty(&dirty_roots)) {
drop_dirty_roots(root, &dirty_roots);
goto again;
}
return 0;
}
#if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,18)
void btrfs_transaction_cleaner(void *p)
#else
void btrfs_transaction_cleaner(struct work_struct *work)
#endif
{
#if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,18)
struct btrfs_fs_info *fs_info = p;
#else
struct btrfs_fs_info *fs_info = container_of(work,
struct btrfs_fs_info,
trans_work.work);
#endif
struct btrfs_root *root = fs_info->tree_root;
struct btrfs_transaction *cur;
struct btrfs_trans_handle *trans;
unsigned long now;
unsigned long delay = HZ * 30;
int ret;
smp_mb();
if (root->fs_info->closing)
goto out;
mutex_lock(&root->fs_info->trans_mutex);
cur = root->fs_info->running_transaction;
if (!cur) {
mutex_unlock(&root->fs_info->trans_mutex);
goto out;
}
now = get_seconds();
if (now < cur->start_time || now - cur->start_time < 30) {
mutex_unlock(&root->fs_info->trans_mutex);
delay = HZ * 5;
goto out;
}
mutex_unlock(&root->fs_info->trans_mutex);
btrfs_defrag_dirty_roots(root->fs_info);
trans = btrfs_start_transaction(root, 1);
ret = btrfs_commit_transaction(trans, root);
out:
btrfs_clean_old_snapshots(root);
btrfs_transaction_queue_work(root, delay);
}
void btrfs_transaction_queue_work(struct btrfs_root *root, int delay)
{
if (!root->fs_info->closing)
queue_delayed_work(trans_wq, &root->fs_info->trans_work, delay);
}
void btrfs_transaction_flush_work(struct btrfs_root *root)
{
cancel_delayed_work(&root->fs_info->trans_work);
flush_workqueue(trans_wq);
}
void __init btrfs_init_transaction_sys(void)
{
trans_wq = create_workqueue("btrfs-transaction");
}
void btrfs_exit_transaction_sys(void)
{
destroy_workqueue(trans_wq);
}

View File

@ -82,16 +82,6 @@ int btrfs_write_and_wait_transaction(struct btrfs_trans_handle *trans,
int btrfs_commit_tree_roots(struct btrfs_trans_handle *trans,
struct btrfs_root *root);
#if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,18)
void btrfs_transaction_cleaner(void *p);
#else
void btrfs_transaction_cleaner(struct work_struct *work);
#endif
void btrfs_transaction_flush_work(struct btrfs_root *root);
void btrfs_transaction_queue_work(struct btrfs_root *root, int delay);
void btrfs_init_transaction_sys(void);
void btrfs_exit_transaction_sys(void);
int btrfs_add_dead_root(struct btrfs_root *root, struct btrfs_root *latest,
struct list_head *dead_list);
int btrfs_defrag_dirty_roots(struct btrfs_fs_info *info);

View File

@ -271,13 +271,17 @@ int btrfs_close_extra_devices(struct btrfs_fs_devices *fs_devices)
list_for_each(cur, head) {
device = list_entry(cur, struct btrfs_device, dev_list);
if (!device->in_fs_metadata) {
if (device->bdev) {
close_bdev_excl(device->bdev);
fs_devices->open_devices--;
}
struct block_device *bdev;
list_del(&device->dev_list);
list_del(&device->dev_alloc_list);
fs_devices->num_devices--;
if (device->bdev) {
bdev = device->bdev;
fs_devices->open_devices--;
mutex_unlock(&uuid_mutex);
close_bdev_excl(bdev);
mutex_lock(&uuid_mutex);
}
kfree(device->name);
kfree(device);
goto again;