GitHub-Mirror/Star64_linux
2
0
Fork 0
mirror of https://github.com/Fishwaldo/Star64_linux.git synced 2025-06-23 07:01:23 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions

Btrfs: fix a bug in checking whether a inode is already in log

Browse source 
This is based on Josef's "Btrfs: turbo charge fsync".

The current btrfs checks if an inode is in log by comparing
root's last_log_commit to inode's last_sub_trans[2].

But the problem is that this root->last_log_commit is shared among
inodes.

Say we have N inodes to be logged, after the first inode,
root's last_log_commit is updated and the N-1 remained files will
be skipped.

This fixes the bug by keeping a local copy of root's last_log_commit
inside each inode and this local copy will be maintained itself.

[1]: we regard each log transaction as a subset of btrfs's transaction,
i.e. sub_trans

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
This commit is contained in:
Liu Bo 2012-08-29 01:07:55 -06:00 • committed by Chris Mason
parent 321f0e7022
commit 46d8bc3424
4 changed files with 10 additions and 8 deletions
Download patch file Download diff file Expand all files Collapse all files

14
fs/btrfs/btrfs_inode.h
View file

@ -144,6 +144,9 @@ struct btrfs_inode {
/* flags field from the on disk inode */
u32 flags;
/* a local copy of root's last_log_commit */
unsigned long last_log_commit;
/*
* Counters to keep track of the number of extent item's we may use due
* to delalloc and such. outstanding_extents is the number of extent
@ -203,15 +206,10 @@ static inline bool btrfs_is_free_space_inode(struct inode *inode)
static inline int btrfs_inode_in_log(struct inode *inode, u64 generation)
{
struct btrfs_root *root = BTRFS_I(inode)->root;
int ret = 0;
mutex_lock(&root->log_mutex);
if (BTRFS_I(inode)->logged_trans == generation &&
BTRFS_I(inode)->last_sub_trans <= root->last_log_commit)
ret = 1;
mutex_unlock(&root->log_mutex);
return ret;
BTRFS_I(inode)->last_sub_trans <= BTRFS_I(inode)->last_log_commit)
return 1;
return 0;
}
#endif