p71924506
/
linux_old1
1
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

btrfs: tweak free space tree bitmap allocation 

The requested bitmap size varies, observed numbers were < 4K up to 16K.
Using vmalloc unconditionally would be too heavy, we'll try contiguous
allocations first and fall back to vmalloc if there's no contig memory.

Signed-off-by: David Sterba <dsterba@suse.com>
This commit is contained in:
David Sterba 2016-01-22 17:16:18 +01:00
parent 8cce83ba50
commit 79b134a22b
1 changed files with 16 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

18
fs/btrfs/free-space-tree.c
View File

@ -153,6 +153,20 @@ static inline u32 free_space_bitmap_size(u64 size, u32 sectorsize)
static unsigned long *alloc_bitmap(u32 bitmap_size)
{
void *mem;
/*
* The allocation size varies, observed numbers were < 4K up to 16K.
* Using vmalloc unconditionally would be too heavy, we'll try
* contiguous allocations first.
*/
if (bitmap_size <= PAGE_SIZE)
return kzalloc(bitmap_size, GFP_NOFS);
mem = kzalloc(bitmap_size, GFP_NOFS | __GFP_HIGHMEM | __GFP_NOWARN);
if (mem)
return mem;
return __vmalloc(bitmap_size, GFP_NOFS | __GFP_HIGHMEM | __GFP_ZERO,
PAGE_KERNEL);
}
@ -289,7 +303,7 @@ int convert_free_space_to_bitmaps(struct btrfs_trans_handle *trans,
ret = 0;
out:
vfree(bitmap);
kvfree(bitmap);
if (ret)
btrfs_abort_transaction(trans, root, ret);
return ret;
@ -438,7 +452,7 @@ int convert_free_space_to_extents(struct btrfs_trans_handle *trans,
ret = 0;
out:
vfree(bitmap);
kvfree(bitmap);
if (ret)
btrfs_abort_transaction(trans, root, ret);
return ret;