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btrfs: remove recalc_thresholds from free space ops

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After removing the inode number cache that was using the free space
cache code, we can remove at least the recalc_thresholds callback from
the ops. Both code and tests use the same callback function. It's moved
before its first use.

The use_bitmaps callback is still needed by tests to create some
extents/bitmap setup.

Signed-off-by: David Sterba <dsterba@suse.com>
This commit is contained in:
David Sterba 2020-12-03 17:18:38 +01:00
parent f0d1219def
commit fa598b0696
3 changed files with 42 additions and 46 deletions
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86
fs/btrfs/free-space-cache.c
View File

@ -597,6 +597,44 @@ static int io_ctl_read_bitmap(struct btrfs_io_ctl *io_ctl,
return 0;
}
static void recalculate_thresholds(struct btrfs_free_space_ctl *ctl)
{
struct btrfs_block_group *block_group = ctl->private;
u64 max_bytes;
u64 bitmap_bytes;
u64 extent_bytes;
u64 size = block_group->length;
u64 bytes_per_bg = BITS_PER_BITMAP * ctl->unit;
u64 max_bitmaps = div64_u64(size + bytes_per_bg - 1, bytes_per_bg);
max_bitmaps = max_t(u64, max_bitmaps, 1);
ASSERT(ctl->total_bitmaps <= max_bitmaps);
/*
* We are trying to keep the total amount of memory used per 1GiB of
* space to be MAX_CACHE_BYTES_PER_GIG. However, with a reclamation
* mechanism of pulling extents >= FORCE_EXTENT_THRESHOLD out of
* bitmaps, we may end up using more memory than this.
*/
if (size < SZ_1G)
max_bytes = MAX_CACHE_BYTES_PER_GIG;
else
max_bytes = MAX_CACHE_BYTES_PER_GIG * div_u64(size, SZ_1G);
bitmap_bytes = ctl->total_bitmaps * ctl->unit;
/*
* we want the extent entry threshold to always be at most 1/2 the max
* bytes we can have, or whatever is less than that.
*/
extent_bytes = max_bytes - bitmap_bytes;
extent_bytes = min_t(u64, extent_bytes, max_bytes >> 1);
ctl->extents_thresh =
div_u64(extent_bytes, sizeof(struct btrfs_free_space));
}
static int __load_free_space_cache(struct btrfs_root *root, struct inode *inode,
struct btrfs_free_space_ctl *ctl,
struct btrfs_path *path, u64 offset)
@ -715,7 +753,7 @@ static int __load_free_space_cache(struct btrfs_root *root, struct inode *inode,
spin_lock(&ctl->tree_lock);
ret = link_free_space(ctl, e);
ctl->total_bitmaps++;
ctl->op->recalc_thresholds(ctl);
recalculate_thresholds(ctl);
spin_unlock(&ctl->tree_lock);
if (ret) {
btrfs_err(fs_info,
@ -1632,44 +1670,6 @@ static int link_free_space(struct btrfs_free_space_ctl *ctl,
return ret;
}
static void recalculate_thresholds(struct btrfs_free_space_ctl *ctl)
{
struct btrfs_block_group *block_group = ctl->private;
u64 max_bytes;
u64 bitmap_bytes;
u64 extent_bytes;
u64 size = block_group->length;
u64 bytes_per_bg = BITS_PER_BITMAP * ctl->unit;
u64 max_bitmaps = div64_u64(size + bytes_per_bg - 1, bytes_per_bg);
max_bitmaps = max_t(u64, max_bitmaps, 1);
ASSERT(ctl->total_bitmaps <= max_bitmaps);
/*
* We are trying to keep the total amount of memory used per 1GiB of
* space to be MAX_CACHE_BYTES_PER_GIG. However, with a reclamation
* mechanism of pulling extents >= FORCE_EXTENT_THRESHOLD out of
* bitmaps, we may end up using more memory than this.
*/
if (size < SZ_1G)
max_bytes = MAX_CACHE_BYTES_PER_GIG;
else
max_bytes = MAX_CACHE_BYTES_PER_GIG * div_u64(size, SZ_1G);
bitmap_bytes = ctl->total_bitmaps * ctl->unit;
/*
* we want the extent entry threshold to always be at most 1/2 the max
* bytes we can have, or whatever is less than that.
*/
extent_bytes = max_bytes - bitmap_bytes;
extent_bytes = min_t(u64, extent_bytes, max_bytes >> 1);
ctl->extents_thresh =
div_u64(extent_bytes, sizeof(struct btrfs_free_space));
}
static inline void __bitmap_clear_bits(struct btrfs_free_space_ctl *ctl,
struct btrfs_free_space *info,
u64 offset, u64 bytes)
@ -1881,8 +1881,7 @@ static void add_new_bitmap(struct btrfs_free_space_ctl *ctl,
INIT_LIST_HEAD(&info->list);
link_free_space(ctl, info);
ctl->total_bitmaps++;
ctl->op->recalc_thresholds(ctl);
recalculate_thresholds(ctl);
}
static void free_bitmap(struct btrfs_free_space_ctl *ctl,
@ -1904,7 +1903,7 @@ static void free_bitmap(struct btrfs_free_space_ctl *ctl,
kmem_cache_free(btrfs_free_space_bitmap_cachep, bitmap_info->bitmap);
kmem_cache_free(btrfs_free_space_cachep, bitmap_info);
ctl->total_bitmaps--;
ctl->op->recalc_thresholds(ctl);
recalculate_thresholds(ctl);
}
static noinline int remove_from_bitmap(struct btrfs_free_space_ctl *ctl,
@ -2071,7 +2070,6 @@ static bool use_bitmap(struct btrfs_free_space_ctl *ctl,
}
static const struct btrfs_free_space_op free_space_op = {
.recalc_thresholds = recalculate_thresholds,
.use_bitmap = use_bitmap,
};
@ -2991,7 +2989,7 @@ out:
kmem_cache_free(btrfs_free_space_bitmap_cachep,
entry->bitmap);
ctl->total_bitmaps--;
ctl->op->recalc_thresholds(ctl);
recalculate_thresholds(ctl);
} else if (!btrfs_free_space_trimmed(entry)) {
ctl->discardable_extents[BTRFS_STAT_CURR]--;
}

1
fs/btrfs/free-space-cache.h
View File

@ -60,7 +60,6 @@ struct btrfs_free_space_ctl {
};
struct btrfs_free_space_op {
void (*recalc_thresholds)(struct btrfs_free_space_ctl *ctl);
bool (*use_bitmap)(struct btrfs_free_space_ctl *ctl,
struct btrfs_free_space *info);
};

1
fs/btrfs/tests/free-space-tests.c
View File

@ -399,7 +399,6 @@ test_steal_space_from_bitmap_to_extent(struct btrfs_block_group *cache,
u64 offset;
u64 max_extent_size;
const struct btrfs_free_space_op test_free_space_ops = {
.recalc_thresholds = cache->free_space_ctl->op->recalc_thresholds,
.use_bitmap = test_use_bitmap,
};
const struct btrfs_free_space_op *orig_free_space_ops;