[XFS] Use the inode tree for finding dirty inodes

Update xfs_sync_inodes to walk the inode radix tree cache to find dirty
inodes. This removes a huge bunch of nasty, messy code for traversing the
mount inode list safely and removes another user of the mount inode list.

Version 3 o rediff against new linux-2.6/xfs_sync.c code

Version 2 o add comment explaining use of gang lookups for a single inode
o use IRELE, not VN_RELE o move check for ag initialisation to caller.

SGI-PV: 988139

SGI-Modid: xfs-linux-melb:xfs-kern:32290a

Signed-off-by: David Chinner <david@fromorbit.com>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
Signed-off-by: Christoph Hellwig <hch@infradead.org>
This commit is contained in:
David Chinner 2008-10-30 17:07:29 +11:00 committed by Lachlan McIlroy
parent 2f8a3ce1c2
commit 683a897080

View file

@ -121,81 +121,180 @@ xfs_sync(
}
/*
* xfs sync routine for internal use
*
* This routine supports all of the flags defined for the generic vfs_sync
* interface as explained above under xfs_sync.
*
* Sync all the inodes in the given AG according to the
* direction given by the flags.
*/
STATIC int
xfs_sync_inodes_ag(
xfs_mount_t *mp,
int ag,
int flags,
int *bypassed)
{
xfs_inode_t *ip = NULL;
struct inode *vp = NULL;
xfs_perag_t *pag = &mp->m_perag[ag];
boolean_t vnode_refed = B_FALSE;
int nr_found;
int first_index = 0;
int error = 0;
int last_error = 0;
int fflag = XFS_B_ASYNC;
int lock_flags = XFS_ILOCK_SHARED;
if (flags & SYNC_DELWRI)
fflag = XFS_B_DELWRI;
if (flags & SYNC_WAIT)
fflag = 0; /* synchronous overrides all */
if (flags & (SYNC_DELWRI | SYNC_CLOSE)) {
/*
* We need the I/O lock if we're going to call any of
* the flush/inval routines.
*/
lock_flags |= XFS_IOLOCK_SHARED;
}
do {
/*
* use a gang lookup to find the next inode in the tree
* as the tree is sparse and a gang lookup walks to find
* the number of objects requested.
*/
read_lock(&pag->pag_ici_lock);
nr_found = radix_tree_gang_lookup(&pag->pag_ici_root,
(void**)&ip, first_index, 1);
if (!nr_found) {
read_unlock(&pag->pag_ici_lock);
break;
}
/* update the index for the next lookup */
first_index = XFS_INO_TO_AGINO(mp, ip->i_ino + 1);
/*
* skip inodes in reclaim. Let xfs_syncsub do that for
* us so we don't need to worry.
*/
vp = VFS_I(ip);
if (!vp) {
read_unlock(&pag->pag_ici_lock);
continue;
}
/* bad inodes are dealt with elsewhere */
if (VN_BAD(vp)) {
read_unlock(&pag->pag_ici_lock);
continue;
}
/* nothing to sync during shutdown */
if (XFS_FORCED_SHUTDOWN(mp) && !(flags & SYNC_CLOSE)) {
read_unlock(&pag->pag_ici_lock);
return 0;
}
/*
* The inode lock here actually coordinates with the almost
* spurious inode lock in xfs_ireclaim() to prevent the vnode
* we handle here without a reference from being freed while we
* reference it. If we lock the inode while it's on the mount
* list here, then the spurious inode lock in xfs_ireclaim()
* after the inode is pulled from the mount list will sleep
* until we release it here. This keeps the vnode from being
* freed while we reference it.
*/
if (xfs_ilock_nowait(ip, lock_flags) == 0) {
vp = vn_grab(vp);
read_unlock(&pag->pag_ici_lock);
if (!vp)
continue;
xfs_ilock(ip, lock_flags);
ASSERT(vp == VFS_I(ip));
ASSERT(ip->i_mount == mp);
vnode_refed = B_TRUE;
} else {
/* safe to unlock here as we have a reference */
read_unlock(&pag->pag_ici_lock);
}
/*
* If we have to flush data or wait for I/O completion
* we need to drop the ilock that we currently hold.
* If we need to drop the lock, insert a marker if we
* have not already done so.
*/
if (flags & SYNC_CLOSE) {
xfs_iunlock(ip, XFS_ILOCK_SHARED);
if (XFS_FORCED_SHUTDOWN(mp))
xfs_tosspages(ip, 0, -1, FI_REMAPF);
else
error = xfs_flushinval_pages(ip, 0, -1,
FI_REMAPF);
/* wait for I/O on freeze */
if (flags & SYNC_IOWAIT)
vn_iowait(ip);
xfs_ilock(ip, XFS_ILOCK_SHARED);
}
if ((flags & SYNC_DELWRI) && VN_DIRTY(vp)) {
xfs_iunlock(ip, XFS_ILOCK_SHARED);
error = xfs_flush_pages(ip, 0, -1, fflag, FI_NONE);
if (flags & SYNC_IOWAIT)
vn_iowait(ip);
xfs_ilock(ip, XFS_ILOCK_SHARED);
}
if ((flags & SYNC_ATTR) && !xfs_inode_clean(ip)) {
if (flags & SYNC_WAIT) {
xfs_iflock(ip);
if (!xfs_inode_clean(ip))
error = xfs_iflush(ip, XFS_IFLUSH_SYNC);
else
xfs_ifunlock(ip);
} else if (xfs_iflock_nowait(ip)) {
if (!xfs_inode_clean(ip))
error = xfs_iflush(ip, XFS_IFLUSH_DELWRI);
else
xfs_ifunlock(ip);
} else if (bypassed) {
(*bypassed)++;
}
}
if (lock_flags)
xfs_iunlock(ip, lock_flags);
if (vnode_refed) {
IRELE(ip);
vnode_refed = B_FALSE;
}
if (error)
last_error = error;
/*
* bail out if the filesystem is corrupted.
*/
if (error == EFSCORRUPTED)
return XFS_ERROR(error);
} while (nr_found);
return last_error;
}
int
xfs_sync_inodes(
xfs_mount_t *mp,
int flags,
int *bypassed)
{
xfs_inode_t *ip = NULL;
struct inode *vp = NULL;
int error;
int last_error;
uint64_t fflag;
uint lock_flags;
uint base_lock_flags;
boolean_t mount_locked;
boolean_t vnode_refed;
int preempt;
xfs_iptr_t *ipointer;
#ifdef DEBUG
boolean_t ipointer_in = B_FALSE;
#define IPOINTER_SET ipointer_in = B_TRUE
#define IPOINTER_CLR ipointer_in = B_FALSE
#else
#define IPOINTER_SET
#define IPOINTER_CLR
#endif
/* Insert a marker record into the inode list after inode ip. The list
* must be locked when this is called. After the call the list will no
* longer be locked.
*/
#define IPOINTER_INSERT(ip, mp) { \
ASSERT(ipointer_in == B_FALSE); \
ipointer->ip_mnext = ip->i_mnext; \
ipointer->ip_mprev = ip; \
ip->i_mnext = (xfs_inode_t *)ipointer; \
ipointer->ip_mnext->i_mprev = (xfs_inode_t *)ipointer; \
preempt = 0; \
XFS_MOUNT_IUNLOCK(mp); \
mount_locked = B_FALSE; \
IPOINTER_SET; \
}
/* Remove the marker from the inode list. If the marker was the only item
* in the list then there are no remaining inodes and we should zero out
* the whole list. If we are the current head of the list then move the head
* past us.
*/
#define IPOINTER_REMOVE(ip, mp) { \
ASSERT(ipointer_in == B_TRUE); \
if (ipointer->ip_mnext != (xfs_inode_t *)ipointer) { \
ip = ipointer->ip_mnext; \
ip->i_mprev = ipointer->ip_mprev; \
ipointer->ip_mprev->i_mnext = ip; \
if (mp->m_inodes == (xfs_inode_t *)ipointer) { \
mp->m_inodes = ip; \
} \
} else { \
ASSERT(mp->m_inodes == (xfs_inode_t *)ipointer); \
mp->m_inodes = NULL; \
ip = NULL; \
} \
IPOINTER_CLR; \
}
#define XFS_PREEMPT_MASK 0x7f
ASSERT(!(flags & SYNC_BDFLUSH));
int i;
if (bypassed)
*bypassed = 0;
@ -203,274 +302,16 @@ xfs_sync_inodes(
return 0;
error = 0;
last_error = 0;
preempt = 0;
/* Allocate a reference marker */
ipointer = (xfs_iptr_t *)kmem_zalloc(sizeof(xfs_iptr_t), KM_SLEEP);
fflag = XFS_B_ASYNC; /* default is don't wait */
if (flags & SYNC_DELWRI)
fflag = XFS_B_DELWRI;
if (flags & SYNC_WAIT)
fflag = 0; /* synchronous overrides all */
base_lock_flags = XFS_ILOCK_SHARED;
if (flags & (SYNC_DELWRI | SYNC_CLOSE)) {
/*
* We need the I/O lock if we're going to call any of
* the flush/inval routines.
*/
base_lock_flags |= XFS_IOLOCK_SHARED;
}
XFS_MOUNT_ILOCK(mp);
ip = mp->m_inodes;
mount_locked = B_TRUE;
vnode_refed = B_FALSE;
IPOINTER_CLR;
do {
ASSERT(ipointer_in == B_FALSE);
ASSERT(vnode_refed == B_FALSE);
lock_flags = base_lock_flags;
/*
* There were no inodes in the list, just break out
* of the loop.
*/
if (ip == NULL) {
break;
}
/*
* We found another sync thread marker - skip it
*/
if (ip->i_mount == NULL) {
ip = ip->i_mnext;
for (i = 0; i < mp->m_sb.sb_agcount; i++) {
if (!mp->m_perag[i].pag_ici_init)
continue;
}
vp = VFS_I(ip);
/*
* If the vnode is gone then this is being torn down,
* call reclaim if it is flushed, else let regular flush
* code deal with it later in the loop.
*/
if (vp == NULL) {
/* Skip ones already in reclaim */
if (ip->i_flags & XFS_IRECLAIM) {
ip = ip->i_mnext;
continue;
}
if (xfs_ilock_nowait(ip, XFS_ILOCK_EXCL) == 0) {
ip = ip->i_mnext;
} else if ((xfs_ipincount(ip) == 0) &&
xfs_iflock_nowait(ip)) {
IPOINTER_INSERT(ip, mp);
xfs_finish_reclaim(ip, 1,
XFS_IFLUSH_DELWRI_ELSE_ASYNC);
XFS_MOUNT_ILOCK(mp);
mount_locked = B_TRUE;
IPOINTER_REMOVE(ip, mp);
} else {
xfs_iunlock(ip, XFS_ILOCK_EXCL);
ip = ip->i_mnext;
}
continue;
}
if (VN_BAD(vp)) {
ip = ip->i_mnext;
continue;
}
if (XFS_FORCED_SHUTDOWN(mp) && !(flags & SYNC_CLOSE)) {
XFS_MOUNT_IUNLOCK(mp);
kmem_free(ipointer);
return 0;
}
/*
* Try to lock without sleeping. We're out of order with
* the inode list lock here, so if we fail we need to drop
* the mount lock and try again. If we're called from
* bdflush() here, then don't bother.
*
* The inode lock here actually coordinates with the
* almost spurious inode lock in xfs_ireclaim() to prevent
* the vnode we handle here without a reference from
* being freed while we reference it. If we lock the inode
* while it's on the mount list here, then the spurious inode
* lock in xfs_ireclaim() after the inode is pulled from
* the mount list will sleep until we release it here.
* This keeps the vnode from being freed while we reference
* it.
*/
if (xfs_ilock_nowait(ip, lock_flags) == 0) {
if (vp == NULL) {
ip = ip->i_mnext;
continue;
}
vp = vn_grab(vp);
if (vp == NULL) {
ip = ip->i_mnext;
continue;
}
IPOINTER_INSERT(ip, mp);
xfs_ilock(ip, lock_flags);
ASSERT(vp == VFS_I(ip));
ASSERT(ip->i_mount == mp);
vnode_refed = B_TRUE;
}
/* From here on in the loop we may have a marker record
* in the inode list.
*/
/*
* If we have to flush data or wait for I/O completion
* we need to drop the ilock that we currently hold.
* If we need to drop the lock, insert a marker if we
* have not already done so.
*/
if ((flags & (SYNC_CLOSE|SYNC_IOWAIT)) ||
((flags & SYNC_DELWRI) && VN_DIRTY(vp))) {
if (mount_locked) {
IPOINTER_INSERT(ip, mp);
}
xfs_iunlock(ip, XFS_ILOCK_SHARED);
if (flags & SYNC_CLOSE) {
/* Shutdown case. Flush and invalidate. */
if (XFS_FORCED_SHUTDOWN(mp))
xfs_tosspages(ip, 0, -1,
FI_REMAPF);
else
error = xfs_flushinval_pages(ip,
0, -1, FI_REMAPF);
} else if ((flags & SYNC_DELWRI) && VN_DIRTY(vp)) {
error = xfs_flush_pages(ip, 0,
-1, fflag, FI_NONE);
}
/*
* When freezing, we need to wait ensure all I/O (including direct
* I/O) is complete to ensure no further data modification can take
* place after this point
*/
if (flags & SYNC_IOWAIT)
vn_iowait(ip);
xfs_ilock(ip, XFS_ILOCK_SHARED);
}
if ((flags & SYNC_ATTR) &&
(ip->i_update_core ||
(ip->i_itemp && ip->i_itemp->ili_format.ilf_fields))) {
if (mount_locked)
IPOINTER_INSERT(ip, mp);
if (flags & SYNC_WAIT) {
xfs_iflock(ip);
error = xfs_iflush(ip, XFS_IFLUSH_SYNC);
/*
* If we can't acquire the flush lock, then the inode
* is already being flushed so don't bother waiting.
*
* If we can lock it then do a delwri flush so we can
* combine multiple inode flushes in each disk write.
*/
} else if (xfs_iflock_nowait(ip)) {
error = xfs_iflush(ip, XFS_IFLUSH_DELWRI);
} else if (bypassed) {
(*bypassed)++;
}
}
if (lock_flags != 0) {
xfs_iunlock(ip, lock_flags);
}
if (vnode_refed) {
/*
* If we had to take a reference on the vnode
* above, then wait until after we've unlocked
* the inode to release the reference. This is
* because we can be already holding the inode
* lock when IRELE() calls xfs_inactive().
*
* Make sure to drop the mount lock before calling
* IRELE() so that we don't trip over ourselves if
* we have to go for the mount lock again in the
* inactive code.
*/
if (mount_locked) {
IPOINTER_INSERT(ip, mp);
}
IRELE(ip);
vnode_refed = B_FALSE;
}
if (error) {
error = xfs_sync_inodes_ag(mp, i, flags, bypassed);
if (error)
last_error = error;
}
/*
* bail out if the filesystem is corrupted.
*/
if (error == EFSCORRUPTED) {
if (!mount_locked) {
XFS_MOUNT_ILOCK(mp);
IPOINTER_REMOVE(ip, mp);
}
XFS_MOUNT_IUNLOCK(mp);
ASSERT(ipointer_in == B_FALSE);
kmem_free(ipointer);
return XFS_ERROR(error);
}
/* Let other threads have a chance at the mount lock
* if we have looped many times without dropping the
* lock.
*/
if ((++preempt & XFS_PREEMPT_MASK) == 0) {
if (mount_locked) {
IPOINTER_INSERT(ip, mp);
}
}
if (mount_locked == B_FALSE) {
XFS_MOUNT_ILOCK(mp);
mount_locked = B_TRUE;
IPOINTER_REMOVE(ip, mp);
continue;
}
ASSERT(ipointer_in == B_FALSE);
ip = ip->i_mnext;
} while (ip != mp->m_inodes);
XFS_MOUNT_IUNLOCK(mp);
ASSERT(ipointer_in == B_FALSE);
kmem_free(ipointer);
if (error == EFSCORRUPTED)
break;
}
return XFS_ERROR(last_error);
}