[XFS] replace inode flush semaphore with a completion

Use the new completion flush code to implement the inode flush lock.
Removes one of the final users of semaphores in the XFS code base.

SGI-PV: 981498

SGI-Modid: xfs-linux-melb:xfs-kern:31817a

Signed-off-by: David Chinner <david@fromorbit.com>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
This commit is contained in:
David Chinner 2008-08-13 16:41:16 +10:00 committed by Lachlan McIlroy
parent 39d2f1ab2a
commit c63942d3ee
4 changed files with 39 additions and 40 deletions

View File

@ -216,7 +216,14 @@ xfs_iget_core(
mrlock_init(&ip->i_iolock, MRLOCK_BARRIER, "xfsio", ip->i_ino);
init_waitqueue_head(&ip->i_ipin_wait);
atomic_set(&ip->i_pincount, 0);
initnsema(&ip->i_flock, 1, "xfsfino");
/*
* Because we want to use a counting completion, complete
* the flush completion once to allow a single access to
* the flush completion without blocking.
*/
init_completion(&ip->i_flush);
complete(&ip->i_flush);
if (lock_flags)
xfs_ilock(ip, lock_flags);
@ -783,26 +790,3 @@ xfs_isilocked(
}
#endif
/*
* The following three routines simply manage the i_flock
* semaphore embedded in the inode. This semaphore synchronizes
* processes attempting to flush the in-core inode back to disk.
*/
void
xfs_iflock(xfs_inode_t *ip)
{
psema(&(ip->i_flock), PINOD|PLTWAIT);
}
int
xfs_iflock_nowait(xfs_inode_t *ip)
{
return (cpsema(&(ip->i_flock)));
}
void
xfs_ifunlock(xfs_inode_t *ip)
{
ASSERT(issemalocked(&(ip->i_flock)));
vsema(&(ip->i_flock));
}

View File

@ -2626,7 +2626,6 @@ xfs_idestroy(
xfs_idestroy_fork(ip, XFS_ATTR_FORK);
mrfree(&ip->i_lock);
mrfree(&ip->i_iolock);
freesema(&ip->i_flock);
#ifdef XFS_INODE_TRACE
ktrace_free(ip->i_trace);
@ -3044,10 +3043,10 @@ xfs_iflush_cluster(
/*
* xfs_iflush() will write a modified inode's changes out to the
* inode's on disk home. The caller must have the inode lock held
* in at least shared mode and the inode flush semaphore must be
* held as well. The inode lock will still be held upon return from
* in at least shared mode and the inode flush completion must be
* active as well. The inode lock will still be held upon return from
* the call and the caller is free to unlock it.
* The inode flush lock will be unlocked when the inode reaches the disk.
* The inode flush will be completed when the inode reaches the disk.
* The flags indicate how the inode's buffer should be written out.
*/
int
@ -3066,7 +3065,7 @@ xfs_iflush(
XFS_STATS_INC(xs_iflush_count);
ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL|XFS_ILOCK_SHARED));
ASSERT(issemalocked(&(ip->i_flock)));
ASSERT(!completion_done(&ip->i_flush));
ASSERT(ip->i_d.di_format != XFS_DINODE_FMT_BTREE ||
ip->i_d.di_nextents > ip->i_df.if_ext_max);
@ -3229,7 +3228,7 @@ xfs_iflush_int(
#endif
ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL|XFS_ILOCK_SHARED));
ASSERT(issemalocked(&(ip->i_flock)));
ASSERT(!completion_done(&ip->i_flush));
ASSERT(ip->i_d.di_format != XFS_DINODE_FMT_BTREE ||
ip->i_d.di_nextents > ip->i_df.if_ext_max);

View File

@ -223,7 +223,7 @@ typedef struct xfs_inode {
struct xfs_inode_log_item *i_itemp; /* logging information */
mrlock_t i_lock; /* inode lock */
mrlock_t i_iolock; /* inode IO lock */
sema_t i_flock; /* inode flush lock */
struct completion i_flush; /* inode flush completion q */
atomic_t i_pincount; /* inode pin count */
wait_queue_head_t i_ipin_wait; /* inode pinning wait queue */
spinlock_t i_flags_lock; /* inode i_flags lock */
@ -482,11 +482,8 @@ int xfs_ilock_nowait(xfs_inode_t *, uint);
void xfs_iunlock(xfs_inode_t *, uint);
void xfs_ilock_demote(xfs_inode_t *, uint);
int xfs_isilocked(xfs_inode_t *, uint);
void xfs_iflock(xfs_inode_t *);
int xfs_iflock_nowait(xfs_inode_t *);
uint xfs_ilock_map_shared(xfs_inode_t *);
void xfs_iunlock_map_shared(xfs_inode_t *, uint);
void xfs_ifunlock(xfs_inode_t *);
void xfs_ireclaim(xfs_inode_t *);
int xfs_finish_reclaim(xfs_inode_t *, int, int);
int xfs_finish_reclaim_all(struct xfs_mount *, int);
@ -580,6 +577,26 @@ extern struct kmem_zone *xfs_ifork_zone;
extern struct kmem_zone *xfs_inode_zone;
extern struct kmem_zone *xfs_ili_zone;
/*
* Manage the i_flush queue embedded in the inode. This completion
* queue synchronizes processes attempting to flush the in-core
* inode back to disk.
*/
static inline void xfs_iflock(xfs_inode_t *ip)
{
wait_for_completion(&ip->i_flush);
}
static inline int xfs_iflock_nowait(xfs_inode_t *ip)
{
return try_wait_for_completion(&ip->i_flush);
}
static inline void xfs_ifunlock(xfs_inode_t *ip)
{
complete(&ip->i_flush);
}
#endif /* __KERNEL__ */
#endif /* __XFS_INODE_H__ */

View File

@ -779,11 +779,10 @@ xfs_inode_item_pushbuf(
ASSERT(iip->ili_push_owner == current_pid());
/*
* If flushlock isn't locked anymore, chances are that the
* inode flush completed and the inode was taken off the AIL.
* So, just get out.
* If a flush is not in progress anymore, chances are that the
* inode was taken off the AIL. So, just get out.
*/
if (!issemalocked(&(ip->i_flock)) ||
if (completion_done(&ip->i_flush) ||
((iip->ili_item.li_flags & XFS_LI_IN_AIL) == 0)) {
iip->ili_pushbuf_flag = 0;
xfs_iunlock(ip, XFS_ILOCK_SHARED);
@ -805,7 +804,7 @@ xfs_inode_item_pushbuf(
* If not, we can flush it async.
*/
dopush = ((iip->ili_item.li_flags & XFS_LI_IN_AIL) &&
issemalocked(&(ip->i_flock)));
!completion_done(&ip->i_flush));
iip->ili_pushbuf_flag = 0;
xfs_iunlock(ip, XFS_ILOCK_SHARED);
xfs_buftrace("INODE ITEM PUSH", bp);
@ -858,7 +857,7 @@ xfs_inode_item_push(
ip = iip->ili_inode;
ASSERT(xfs_isilocked(ip, XFS_ILOCK_SHARED));
ASSERT(issemalocked(&(ip->i_flock)));
ASSERT(!completion_done(&ip->i_flush));
/*
* Since we were able to lock the inode's flush lock and
* we found it on the AIL, the inode must be dirty. This