Hello,
This patch updates the allocator for the new space balancing
code. It adds reserved extents accounting, changes a few ENOSPC
check, and makes btrfs_find_block_group not return NULL for
volumes that have been ebalanced.
Regards
Yan Zheng
---
diff -r 4b327f4fcee0 ctree.h
--- a/ctree.h Tue Sep 23 13:14:14 2008 -0400
+++ b/ctree.h Thu Sep 25 16:00:18 2008 +0800
@@ -498,6 +498,7 @@
u64 total_bytes;
u64 bytes_used;
u64 bytes_pinned;
+ u64 bytes_reserved;
int full;
int force_alloc;
struct list_head list;
@@ -519,6 +520,7 @@
struct btrfs_block_group_item item;
spinlock_t lock;
u64 pinned;
+ u64 reserved;
u64 flags;
int cached;
int ro;
diff -r 4b327f4fcee0 extent-tree.c
--- a/extent-tree.c Tue Sep 23 13:14:14 2008 -0400
+++ b/extent-tree.c Thu Sep 25 16:00:18 2008 +0800
@@ -325,12 +325,9 @@
struct btrfs_block_group_cache *cache = *cache_ret;
struct btrfs_free_space *info = NULL;
u64 last;
- u64 total_fs_bytes;
u64 search_start = *start_ret;
WARN_ON(!mutex_is_locked(&root->fs_info->alloc_mutex));
- total_fs_bytes = btrfs_super_total_bytes(&root->fs_info->super_copy);
-
if (!cache)
goto out;
@@ -354,7 +351,7 @@
last = cache->key.objectid + cache->key.offset;
cache = btrfs_lookup_first_block_group(root->fs_info, last);
- if (!cache || cache->key.objectid >= total_fs_bytes)
+ if (!cache)
goto out;
*cache_ret = cache;
@@ -385,7 +382,6 @@
return found;
}
return NULL;
-
}
static struct btrfs_block_group_cache *
@@ -396,7 +392,6 @@
struct btrfs_block_group_cache *cache;
struct btrfs_block_group_cache *found_group = NULL;
struct btrfs_fs_info *info = root->fs_info;
- struct btrfs_space_info *sinfo;
u64 used;
u64 last = 0;
u64 free_check;
@@ -413,7 +408,7 @@
if (shint && block_group_bits(shint, data) && !shint->ro) {
spin_lock(&shint->lock);
used = btrfs_block_group_used(&shint->item);
- if (used + shint->pinned <
+ if (used + shint->pinned + shint->reserved <
div_factor(shint->key.offset, factor)) {
spin_unlock(&shint->lock);
return shint;
@@ -424,7 +419,7 @@
if (hint && !hint->ro && block_group_bits(hint, data)) {
spin_lock(&hint->lock);
used = btrfs_block_group_used(&hint->item);
- if (used + hint->pinned <
+ if (used + hint->pinned + hint->reserved <
div_factor(hint->key.offset, factor)) {
spin_unlock(&hint->lock);
return hint;
@@ -437,27 +432,9 @@
else
last = search_start;
}
- sinfo = __find_space_info(root->fs_info, data);
- if (!sinfo)
- goto found;
-again:
- while(1) {
- struct list_head *l;
-
- cache = NULL;
-
- spin_lock(&sinfo->lock);
- list_for_each(l, &sinfo->block_groups) {
- struct btrfs_block_group_cache *entry;
- entry = list_entry(l, struct btrfs_block_group_cache,
- list);
- if ((entry->key.objectid >= last) &&
- (!cache || (entry->key.objectid <
- cache->key.objectid)))
- cache = entry;
- }
- spin_unlock(&sinfo->lock);
-
+again:
+ while (1) {
+ cache = btrfs_lookup_first_block_group(root->fs_info, last);
if (!cache)
break;
@@ -467,7 +444,8 @@
if (!cache->ro && block_group_bits(cache, data)) {
free_check = div_factor(cache->key.offset, factor);
- if (used + cache->pinned < free_check) {
+ if (used + cache->pinned + cache->reserved <
+ free_check) {
found_group = cache;
spin_unlock(&cache->lock);
goto found;
@@ -1414,6 +1392,7 @@
if (!cache)
break;
+ cache->dirty = 0;
last += cache->key.offset;
err = write_one_cache_group(trans, root,
@@ -1427,8 +1406,6 @@
werr = err;
continue;
}
-
- cache->dirty = 0;
}
btrfs_free_path(path);
mutex_unlock(&root->fs_info->alloc_mutex);
@@ -1460,6 +1437,7 @@
found->total_bytes = total_bytes;
found->bytes_used = bytes_used;
found->bytes_pinned = 0;
+ found->bytes_reserved = 0;
found->full = 0;
found->force_alloc = 0;
*space_info = found;
@@ -1539,8 +1517,8 @@
thresh = div_factor(space_info->total_bytes, 6);
if (!force &&
- (space_info->bytes_used + space_info->bytes_pinned + alloc_bytes) <
- thresh)
+ (space_info->bytes_used + space_info->bytes_pinned +
+ space_info->bytes_reserved + alloc_bytes) < thresh)
goto out;
mutex_lock(&extent_root->fs_info->chunk_mutex);
@@ -1621,7 +1599,6 @@
return cache->key.objectid;
}
-
int btrfs_update_pinned_extents(struct btrfs_root *root,
u64 bytenr, u64 num, int pin)
{
@@ -1639,30 +1616,51 @@
}
while (num > 0) {
cache = btrfs_lookup_block_group(fs_info, bytenr);
- if (!cache) {
- u64 first = first_logical_byte(root, bytenr);
- WARN_ON(first < bytenr);
- len = min(first - bytenr, num);
- } else {
- len = min(num, cache->key.offset -
- (bytenr - cache->key.objectid));
- }
+ BUG_ON(!cache);
+ len = min(num, cache->key.offset -
+ (bytenr - cache->key.objectid));
if (pin) {
- if (cache) {
- spin_lock(&cache->lock);
- cache->pinned += len;
- cache->space_info->bytes_pinned += len;
- spin_unlock(&cache->lock);
- }
+ spin_lock(&cache->lock);
+ cache->pinned += len;
+ cache->space_info->bytes_pinned += len;
+ spin_unlock(&cache->lock);
fs_info->total_pinned += len;
} else {
- if (cache) {
- spin_lock(&cache->lock);
- cache->pinned -= len;
- cache->space_info->bytes_pinned -= len;
- spin_unlock(&cache->lock);
- }
+ spin_lock(&cache->lock);
+ cache->pinned -= len;
+ cache->space_info->bytes_pinned -= len;
+ spin_unlock(&cache->lock);
fs_info->total_pinned -= len;
+ }
+ bytenr += len;
+ num -= len;
+ }
+ return 0;
+}
+
+static int update_reserved_extents(struct btrfs_root *root,
+ u64 bytenr, u64 num, int reserve)
+{
+ u64 len;
+ struct btrfs_block_group_cache *cache;
+ struct btrfs_fs_info *fs_info = root->fs_info;
+
+ WARN_ON(!mutex_is_locked(&root->fs_info->alloc_mutex));
+ while (num > 0) {
+ cache = btrfs_lookup_block_group(fs_info, bytenr);
+ BUG_ON(!cache);
+ len = min(num, cache->key.offset -
+ (bytenr - cache->key.objectid));
+ if (reserve) {
+ spin_lock(&cache->lock);
+ cache->reserved += len;
+ cache->space_info->bytes_reserved += len;
+ spin_unlock(&cache->lock);
+ } else {
+ spin_lock(&cache->lock);
+ cache->reserved -= len;
+ cache->space_info->bytes_reserved -= len;
+ spin_unlock(&cache->lock);
}
bytenr += len;
num -= len;
@@ -2126,6 +2124,7 @@
cache = btrfs_lookup_block_group(root->fs_info, bytenr);
BUG_ON(!cache);
btrfs_add_free_space(cache, bytenr, num_bytes);
+ update_reserved_extents(root, bytenr, num_bytes, 0);
return 0;
}
pin = 1;
@@ -2225,14 +2224,11 @@
search_start = max(search_start, first_logical_byte(root, 0));
orig_search_start = search_start;
- if (search_end == (u64)-1)
- search_end = btrfs_super_total_bytes(&info->super_copy);
-
search_start = max(search_start, hint_byte);
total_needed += empty_size;
new_group:
- block_group = btrfs_lookup_block_group(info, search_start);
+ block_group = btrfs_lookup_first_block_group(info, search_start);
/*
* Ok this looks a little tricky, buts its really simple. First if we
@@ -2257,12 +2253,8 @@
ret = do_chunk_alloc(trans, root,
num_bytes + 2 * 1024 * 1024,
data, 1);
- if (ret < 0) {
- struct btrfs_space_info *info;
-
- info = __find_space_info(root->fs_info, data);
+ if (ret < 0)
goto error;
- }
BUG_ON(ret);
chunk_alloc_done = 1;
search_start = orig_search_start;
@@ -2378,22 +2370,24 @@
struct list_head *l;
printk(KERN_INFO "space_info has %Lu free, is %sfull\n",
- info->total_bytes - info->bytes_used - info->bytes_pinned,
- (info->full) ? "" : "not ");
+ info->total_bytes - info->bytes_used - info->bytes_pinned -
+ info->bytes_reserved, (info->full) ? "" : "not ");
spin_lock(&info->lock);
list_for_each(l, &info->block_groups) {
cache = list_entry(l, struct btrfs_block_group_cache, list);
spin_lock(&cache->lock);
printk(KERN_INFO "block group %Lu has %Lu bytes, %Lu used "
- "%Lu pinned\n",
+ "%Lu pinned %Lu reserved\n",
cache->key.objectid, cache->key.offset,
- btrfs_block_group_used(&cache->item), cache->pinned);
+ btrfs_block_group_used(&cache->item),
+ cache->pinned, cache->reserved);
btrfs_dump_free_space(cache, bytes);
spin_unlock(&cache->lock);
}
spin_unlock(&info->lock);
}
+
static int __btrfs_reserve_extent(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
u64 num_bytes, u64 min_alloc_size,
@@ -2500,6 +2494,7 @@
ret = __btrfs_reserve_extent(trans, root, num_bytes, min_alloc_size,
empty_size, hint_byte, search_end, ins,
data);
+ update_reserved_extents(root, ins->objectid, ins->offset, 1);
maybe_unlock_mutex(root);
return ret;
}
@@ -2625,6 +2620,7 @@
ret = __btrfs_alloc_reserved_extent(trans, root, parent,
root_objectid, ref_generation,
owner, owner_offset, ins);
+ update_reserved_extents(root, ins->objectid, ins->offset, 0);
maybe_unlock_mutex(root);
return ret;
}
@@ -2685,6 +2681,8 @@
owner_objectid, owner_offset, ins);
BUG_ON(ret);
+ } else {
+ update_reserved_extents(root, ins->objectid, ins->offset, 1);
}
maybe_unlock_mutex(root);
return ret;
@@ -3970,10 +3968,6 @@
ret = btrfs_add_block_group_cache(root->fs_info, cache);
BUG_ON(ret);
-
- if (key.objectid >=
- btrfs_super_total_bytes(&info->super_copy))
- break;
}
ret = 0;
error:
--
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