diff options
Diffstat (limited to 'fs/xfs/linux-2.6/xfs_sync.c')
-rw-r--r-- | fs/xfs/linux-2.6/xfs_sync.c | 432 |
1 files changed, 253 insertions, 179 deletions
diff --git a/fs/xfs/linux-2.6/xfs_sync.c b/fs/xfs/linux-2.6/xfs_sync.c index d59c4a65d49..37d33254981 100644 --- a/fs/xfs/linux-2.6/xfs_sync.c +++ b/fs/xfs/linux-2.6/xfs_sync.c @@ -39,42 +39,39 @@ #include <linux/kthread.h> #include <linux/freezer.h> +/* + * The inode lookup is done in batches to keep the amount of lock traffic and + * radix tree lookups to a minimum. The batch size is a trade off between + * lookup reduction and stack usage. This is in the reclaim path, so we can't + * be too greedy. + */ +#define XFS_LOOKUP_BATCH 32 -STATIC xfs_inode_t * -xfs_inode_ag_lookup( - struct xfs_mount *mp, - struct xfs_perag *pag, - uint32_t *first_index, - int tag) +STATIC int +xfs_inode_ag_walk_grab( + struct xfs_inode *ip) { - int nr_found; - struct xfs_inode *ip; + struct inode *inode = VFS_I(ip); - /* - * 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. - */ - if (tag == XFS_ICI_NO_TAG) { - nr_found = radix_tree_gang_lookup(&pag->pag_ici_root, - (void **)&ip, *first_index, 1); - } else { - nr_found = radix_tree_gang_lookup_tag(&pag->pag_ici_root, - (void **)&ip, *first_index, 1, tag); + /* nothing to sync during shutdown */ + if (XFS_FORCED_SHUTDOWN(ip->i_mount)) + return EFSCORRUPTED; + + /* avoid new or reclaimable inodes. Leave for reclaim code to flush */ + if (xfs_iflags_test(ip, XFS_INEW | XFS_IRECLAIMABLE | XFS_IRECLAIM)) + return ENOENT; + + /* If we can't grab the inode, it must on it's way to reclaim. */ + if (!igrab(inode)) + return ENOENT; + + if (is_bad_inode(inode)) { + IRELE(ip); + return ENOENT; } - if (!nr_found) - return NULL; - /* - * Update the index for the next lookup. Catch overflows - * into the next AG range which can occur if we have inodes - * in the last block of the AG and we are currently - * pointing to the last inode. - */ - *first_index = XFS_INO_TO_AGINO(mp, ip->i_ino + 1); - if (*first_index < XFS_INO_TO_AGINO(mp, ip->i_ino)) - return NULL; - return ip; + /* inode is valid */ + return 0; } STATIC int @@ -83,49 +80,75 @@ xfs_inode_ag_walk( struct xfs_perag *pag, int (*execute)(struct xfs_inode *ip, struct xfs_perag *pag, int flags), - int flags, - int tag, - int exclusive, - int *nr_to_scan) + int flags) { uint32_t first_index; int last_error = 0; int skipped; + int done; + int nr_found; restart: + done = 0; skipped = 0; first_index = 0; + nr_found = 0; do { + struct xfs_inode *batch[XFS_LOOKUP_BATCH]; int error = 0; - xfs_inode_t *ip; + int i; - if (exclusive) - write_lock(&pag->pag_ici_lock); - else - read_lock(&pag->pag_ici_lock); - ip = xfs_inode_ag_lookup(mp, pag, &first_index, tag); - if (!ip) { - if (exclusive) - write_unlock(&pag->pag_ici_lock); - else - read_unlock(&pag->pag_ici_lock); + read_lock(&pag->pag_ici_lock); + nr_found = radix_tree_gang_lookup(&pag->pag_ici_root, + (void **)batch, first_index, + XFS_LOOKUP_BATCH); + if (!nr_found) { + read_unlock(&pag->pag_ici_lock); break; } - /* execute releases pag->pag_ici_lock */ - error = execute(ip, pag, flags); - if (error == EAGAIN) { - skipped++; - continue; + /* + * Grab the inodes before we drop the lock. if we found + * nothing, nr == 0 and the loop will be skipped. + */ + for (i = 0; i < nr_found; i++) { + struct xfs_inode *ip = batch[i]; + + if (done || xfs_inode_ag_walk_grab(ip)) + batch[i] = NULL; + + /* + * Update the index for the next lookup. Catch overflows + * into the next AG range which can occur if we have inodes + * in the last block of the AG and we are currently + * pointing to the last inode. + */ + first_index = XFS_INO_TO_AGINO(mp, ip->i_ino + 1); + if (first_index < XFS_INO_TO_AGINO(mp, ip->i_ino)) + done = 1; + } + + /* unlock now we've grabbed the inodes. */ + read_unlock(&pag->pag_ici_lock); + + for (i = 0; i < nr_found; i++) { + if (!batch[i]) + continue; + error = execute(batch[i], pag, flags); + IRELE(batch[i]); + if (error == EAGAIN) { + skipped++; + continue; + } + if (error && last_error != EFSCORRUPTED) + last_error = error; } - if (error) - last_error = error; /* bail out if the filesystem is corrupted. */ if (error == EFSCORRUPTED) break; - } while ((*nr_to_scan)--); + } while (nr_found && !done); if (skipped) { delay(1); @@ -134,110 +157,32 @@ restart: return last_error; } -/* - * Select the next per-ag structure to iterate during the walk. The reclaim - * walk is optimised only to walk AGs with reclaimable inodes in them. - */ -static struct xfs_perag * -xfs_inode_ag_iter_next_pag( - struct xfs_mount *mp, - xfs_agnumber_t *first, - int tag) -{ - struct xfs_perag *pag = NULL; - - if (tag == XFS_ICI_RECLAIM_TAG) { - int found; - int ref; - - spin_lock(&mp->m_perag_lock); - found = radix_tree_gang_lookup_tag(&mp->m_perag_tree, - (void **)&pag, *first, 1, tag); - if (found <= 0) { - spin_unlock(&mp->m_perag_lock); - return NULL; - } - *first = pag->pag_agno + 1; - /* open coded pag reference increment */ - ref = atomic_inc_return(&pag->pag_ref); - spin_unlock(&mp->m_perag_lock); - trace_xfs_perag_get_reclaim(mp, pag->pag_agno, ref, _RET_IP_); - } else { - pag = xfs_perag_get(mp, *first); - (*first)++; - } - return pag; -} - int xfs_inode_ag_iterator( struct xfs_mount *mp, int (*execute)(struct xfs_inode *ip, struct xfs_perag *pag, int flags), - int flags, - int tag, - int exclusive, - int *nr_to_scan) + int flags) { struct xfs_perag *pag; int error = 0; int last_error = 0; xfs_agnumber_t ag; - int nr; - nr = nr_to_scan ? *nr_to_scan : INT_MAX; ag = 0; - while ((pag = xfs_inode_ag_iter_next_pag(mp, &ag, tag))) { - error = xfs_inode_ag_walk(mp, pag, execute, flags, tag, - exclusive, &nr); + while ((pag = xfs_perag_get(mp, ag))) { + ag = pag->pag_agno + 1; + error = xfs_inode_ag_walk(mp, pag, execute, flags); xfs_perag_put(pag); if (error) { last_error = error; if (error == EFSCORRUPTED) break; } - if (nr <= 0) - break; } - if (nr_to_scan) - *nr_to_scan = nr; return XFS_ERROR(last_error); } -/* must be called with pag_ici_lock held and releases it */ -int -xfs_sync_inode_valid( - struct xfs_inode *ip, - struct xfs_perag *pag) -{ - struct inode *inode = VFS_I(ip); - int error = EFSCORRUPTED; - - /* nothing to sync during shutdown */ - if (XFS_FORCED_SHUTDOWN(ip->i_mount)) - goto out_unlock; - - /* avoid new or reclaimable inodes. Leave for reclaim code to flush */ - error = ENOENT; - if (xfs_iflags_test(ip, XFS_INEW | XFS_IRECLAIMABLE | XFS_IRECLAIM)) - goto out_unlock; - - /* If we can't grab the inode, it must on it's way to reclaim. */ - if (!igrab(inode)) - goto out_unlock; - - if (is_bad_inode(inode)) { - IRELE(ip); - goto out_unlock; - } - - /* inode is valid */ - error = 0; -out_unlock: - read_unlock(&pag->pag_ici_lock); - return error; -} - STATIC int xfs_sync_inode_data( struct xfs_inode *ip, @@ -248,10 +193,6 @@ xfs_sync_inode_data( struct address_space *mapping = inode->i_mapping; int error = 0; - error = xfs_sync_inode_valid(ip, pag); - if (error) - return error; - if (!mapping_tagged(mapping, PAGECACHE_TAG_DIRTY)) goto out_wait; @@ -268,7 +209,6 @@ xfs_sync_inode_data( out_wait: if (flags & SYNC_WAIT) xfs_ioend_wait(ip); - IRELE(ip); return error; } @@ -280,10 +220,6 @@ xfs_sync_inode_attr( { int error = 0; - error = xfs_sync_inode_valid(ip, pag); - if (error) - return error; - xfs_ilock(ip, XFS_ILOCK_SHARED); if (xfs_inode_clean(ip)) goto out_unlock; @@ -302,7 +238,6 @@ xfs_sync_inode_attr( out_unlock: xfs_iunlock(ip, XFS_ILOCK_SHARED); - IRELE(ip); return error; } @@ -318,8 +253,7 @@ xfs_sync_data( ASSERT((flags & ~(SYNC_TRYLOCK|SYNC_WAIT)) == 0); - error = xfs_inode_ag_iterator(mp, xfs_sync_inode_data, flags, - XFS_ICI_NO_TAG, 0, NULL); + error = xfs_inode_ag_iterator(mp, xfs_sync_inode_data, flags); if (error) return XFS_ERROR(error); @@ -337,8 +271,7 @@ xfs_sync_attr( { ASSERT((flags & ~SYNC_WAIT) == 0); - return xfs_inode_ag_iterator(mp, xfs_sync_inode_attr, flags, - XFS_ICI_NO_TAG, 0, NULL); + return xfs_inode_ag_iterator(mp, xfs_sync_inode_attr, flags); } STATIC int @@ -668,14 +601,11 @@ xfs_inode_set_reclaim_tag( xfs_perag_put(pag); } -void -__xfs_inode_clear_reclaim_tag( - xfs_mount_t *mp, +STATIC void +__xfs_inode_clear_reclaim( xfs_perag_t *pag, xfs_inode_t *ip) { - radix_tree_tag_clear(&pag->pag_ici_root, - XFS_INO_TO_AGINO(mp, ip->i_ino), XFS_ICI_RECLAIM_TAG); pag->pag_ici_reclaimable--; if (!pag->pag_ici_reclaimable) { /* clear the reclaim tag from the perag radix tree */ @@ -689,6 +619,54 @@ __xfs_inode_clear_reclaim_tag( } } +void +__xfs_inode_clear_reclaim_tag( + xfs_mount_t *mp, + xfs_perag_t *pag, + xfs_inode_t *ip) +{ + radix_tree_tag_clear(&pag->pag_ici_root, + XFS_INO_TO_AGINO(mp, ip->i_ino), XFS_ICI_RECLAIM_TAG); + __xfs_inode_clear_reclaim(pag, ip); +} + +/* + * Grab the inode for reclaim exclusively. + * Return 0 if we grabbed it, non-zero otherwise. + */ +STATIC int +xfs_reclaim_inode_grab( + struct xfs_inode *ip, + int flags) +{ + + /* + * do some unlocked checks first to avoid unnecceary lock traffic. + * The first is a flush lock check, the second is a already in reclaim + * check. Only do these checks if we are not going to block on locks. + */ + if ((flags & SYNC_TRYLOCK) && + (!ip->i_flush.done || __xfs_iflags_test(ip, XFS_IRECLAIM))) { + return 1; + } + + /* + * The radix tree lock here protects a thread in xfs_iget from racing + * with us starting reclaim on the inode. Once we have the + * XFS_IRECLAIM flag set it will not touch us. + */ + spin_lock(&ip->i_flags_lock); + ASSERT_ALWAYS(__xfs_iflags_test(ip, XFS_IRECLAIMABLE)); + if (__xfs_iflags_test(ip, XFS_IRECLAIM)) { + /* ignore as it is already under reclaim */ + spin_unlock(&ip->i_flags_lock); + return 1; + } + __xfs_iflags_set(ip, XFS_IRECLAIM); + spin_unlock(&ip->i_flags_lock); + return 0; +} + /* * Inodes in different states need to be treated differently, and the return * value of xfs_iflush is not sufficient to get this right. The following table @@ -747,23 +725,6 @@ xfs_reclaim_inode( { int error = 0; - /* - * The radix tree lock here protects a thread in xfs_iget from racing - * with us starting reclaim on the inode. Once we have the - * XFS_IRECLAIM flag set it will not touch us. - */ - spin_lock(&ip->i_flags_lock); - ASSERT_ALWAYS(__xfs_iflags_test(ip, XFS_IRECLAIMABLE)); - if (__xfs_iflags_test(ip, XFS_IRECLAIM)) { - /* ignore as it is already under reclaim */ - spin_unlock(&ip->i_flags_lock); - write_unlock(&pag->pag_ici_lock); - return 0; - } - __xfs_iflags_set(ip, XFS_IRECLAIM); - spin_unlock(&ip->i_flags_lock); - write_unlock(&pag->pag_ici_lock); - xfs_ilock(ip, XFS_ILOCK_EXCL); if (!xfs_iflock_nowait(ip)) { if (!(sync_mode & SYNC_WAIT)) @@ -838,6 +799,7 @@ reclaim: if (!radix_tree_delete(&pag->pag_ici_root, XFS_INO_TO_AGINO(ip->i_mount, ip->i_ino))) ASSERT(0); + __xfs_inode_clear_reclaim(pag, ip); write_unlock(&pag->pag_ici_lock); /* @@ -859,13 +821,126 @@ reclaim: } +/* + * Walk the AGs and reclaim the inodes in them. Even if the filesystem is + * corrupted, we still want to try to reclaim all the inodes. If we don't, + * then a shut down during filesystem unmount reclaim walk leak all the + * unreclaimed inodes. + */ +int +xfs_reclaim_inodes_ag( + struct xfs_mount *mp, + int flags, + int *nr_to_scan) +{ + struct xfs_perag *pag; + int error = 0; + int last_error = 0; + xfs_agnumber_t ag; + int trylock = flags & SYNC_TRYLOCK; + int skipped; + +restart: + ag = 0; + skipped = 0; + while ((pag = xfs_perag_get_tag(mp, ag, XFS_ICI_RECLAIM_TAG))) { + unsigned long first_index = 0; + int done = 0; + int nr_found = 0; + + ag = pag->pag_agno + 1; + + if (trylock) { + if (!mutex_trylock(&pag->pag_ici_reclaim_lock)) { + skipped++; + continue; + } + first_index = pag->pag_ici_reclaim_cursor; + } else + mutex_lock(&pag->pag_ici_reclaim_lock); + + do { + struct xfs_inode *batch[XFS_LOOKUP_BATCH]; + int i; + + write_lock(&pag->pag_ici_lock); + nr_found = radix_tree_gang_lookup_tag( + &pag->pag_ici_root, + (void **)batch, first_index, + XFS_LOOKUP_BATCH, + XFS_ICI_RECLAIM_TAG); + if (!nr_found) { + write_unlock(&pag->pag_ici_lock); + break; + } + + /* + * Grab the inodes before we drop the lock. if we found + * nothing, nr == 0 and the loop will be skipped. + */ + for (i = 0; i < nr_found; i++) { + struct xfs_inode *ip = batch[i]; + + if (done || xfs_reclaim_inode_grab(ip, flags)) + batch[i] = NULL; + + /* + * Update the index for the next lookup. Catch + * overflows into the next AG range which can + * occur if we have inodes in the last block of + * the AG and we are currently pointing to the + * last inode. + */ + first_index = XFS_INO_TO_AGINO(mp, ip->i_ino + 1); + if (first_index < XFS_INO_TO_AGINO(mp, ip->i_ino)) + done = 1; + } + + /* unlock now we've grabbed the inodes. */ + write_unlock(&pag->pag_ici_lock); + + for (i = 0; i < nr_found; i++) { + if (!batch[i]) + continue; + error = xfs_reclaim_inode(batch[i], pag, flags); + if (error && last_error != EFSCORRUPTED) + last_error = error; + } + + *nr_to_scan -= XFS_LOOKUP_BATCH; + + } while (nr_found && !done && *nr_to_scan > 0); + + if (trylock && !done) + pag->pag_ici_reclaim_cursor = first_index; + else + pag->pag_ici_reclaim_cursor = 0; + mutex_unlock(&pag->pag_ici_reclaim_lock); + xfs_perag_put(pag); + } + + /* + * if we skipped any AG, and we still have scan count remaining, do + * another pass this time using blocking reclaim semantics (i.e + * waiting on the reclaim locks and ignoring the reclaim cursors). This + * ensure that when we get more reclaimers than AGs we block rather + * than spin trying to execute reclaim. + */ + if (trylock && skipped && *nr_to_scan > 0) { + trylock = 0; + goto restart; + } + return XFS_ERROR(last_error); +} + int xfs_reclaim_inodes( xfs_mount_t *mp, int mode) { - return xfs_inode_ag_iterator(mp, xfs_reclaim_inode, mode, - XFS_ICI_RECLAIM_TAG, 1, NULL); + int nr_to_scan = INT_MAX; + + return xfs_reclaim_inodes_ag(mp, mode, &nr_to_scan); } /* @@ -887,17 +962,16 @@ xfs_reclaim_inode_shrink( if (!(gfp_mask & __GFP_FS)) return -1; - xfs_inode_ag_iterator(mp, xfs_reclaim_inode, 0, - XFS_ICI_RECLAIM_TAG, 1, &nr_to_scan); - /* if we don't exhaust the scan, don't bother coming back */ + xfs_reclaim_inodes_ag(mp, SYNC_TRYLOCK, &nr_to_scan); + /* terminate if we don't exhaust the scan */ if (nr_to_scan > 0) return -1; } reclaimable = 0; ag = 0; - while ((pag = xfs_inode_ag_iter_next_pag(mp, &ag, - XFS_ICI_RECLAIM_TAG))) { + while ((pag = xfs_perag_get_tag(mp, ag, XFS_ICI_RECLAIM_TAG))) { + ag = pag->pag_agno + 1; reclaimable += pag->pag_ici_reclaimable; xfs_perag_put(pag); } |