diff options
| -rw-r--r-- | fs/xfs/xfs_inode.c | 145 |
1 files changed, 67 insertions, 78 deletions
diff --git a/fs/xfs/xfs_inode.c b/fs/xfs/xfs_inode.c index d0414f3..d0a98ba 100644 --- a/fs/xfs/xfs_inode.c +++ b/fs/xfs/xfs_inode.c @@ -329,15 +329,14 @@ xfs_lock_inumorder(int lock_mode, int subclass) } /* - * The following routine will lock n inodes in exclusive mode. - * We assume the caller calls us with the inodes in i_ino order. + * The following routine will lock n inodes in exclusive mode. We assume the + * caller calls us with the inodes in i_ino order. * - * We need to detect deadlock where an inode that we lock - * is in the AIL and we start waiting for another inode that is locked - * by a thread in a long running transaction (such as truncate). This can - * result in deadlock since the long running trans might need to wait - * for the inode we just locked in order to push the tail and free space - * in the log. + * We need to detect deadlock where an inode that we lock is in the AIL and we + * start waiting for another inode that is locked by a thread in a long running + * transaction (such as truncate). This can result in deadlock since the long + * running trans might need to wait for the inode we just locked in order to + * push the tail and free space in the log. */ void xfs_lock_inodes( @@ -348,30 +347,27 @@ xfs_lock_inodes( int attempts = 0, i, j, try_lock; xfs_log_item_t *lp; - ASSERT(ips && (inodes >= 2)); /* we need at least two */ + /* currently supports between 2 and 5 inodes */ + ASSERT(ips && inodes >= 2 && inodes <= 5); try_lock = 0; i = 0; - again: for (; i < inodes; i++) { ASSERT(ips[i]); - if (i && (ips[i] == ips[i-1])) /* Already locked */ + if (i && (ips[i] == ips[i - 1])) /* Already locked */ continue; /* - * If try_lock is not set yet, make sure all locked inodes - * are not in the AIL. - * If any are, set try_lock to be used later. + * If try_lock is not set yet, make sure all locked inodes are + * not in the AIL. If any are, set try_lock to be used later. */ - if (!try_lock) { for (j = (i - 1); j >= 0 && !try_lock; j--) { lp = (xfs_log_item_t *)ips[j]->i_itemp; - if (lp && (lp->li_flags & XFS_LI_IN_AIL)) { + if (lp && (lp->li_flags & XFS_LI_IN_AIL)) try_lock++; - } } } @@ -381,51 +377,42 @@ again: * we can't get any, we must release all we have * and try again. */ + if (!try_lock) { + xfs_ilock(ips[i], xfs_lock_inumorder(lock_mode, i)); + continue; + } + + /* try_lock means we have an inode locked that is in the AIL. */ + ASSERT(i != 0); + if (xfs_ilock_nowait(ips[i], xfs_lock_inumorder(lock_mode, i))) + continue; - if (try_lock) { - /* try_lock must be 0 if i is 0. */ + /* + * Unlock all previous guys and try again. xfs_iunlock will try + * to push the tail if the inode is in the AIL. + */ + attempts++; + for (j = i - 1; j >= 0; j--) { /* - * try_lock means we have an inode locked - * that is in the AIL. + * Check to see if we've already unlocked this one. Not + * the first one going back, and the inode ptr is the + * same. */ - ASSERT(i != 0); - if (!xfs_ilock_nowait(ips[i], xfs_lock_inumorder(lock_mode, i))) { - attempts++; - - /* - * Unlock all previous guys and try again. - * xfs_iunlock will try to push the tail - * if the inode is in the AIL. - */ - - for(j = i - 1; j >= 0; j--) { - - /* - * Check to see if we've already - * unlocked this one. - * Not the first one going back, - * and the inode ptr is the same. - */ - if ((j != (i - 1)) && ips[j] == - ips[j+1]) - continue; - - xfs_iunlock(ips[j], lock_mode); - } + if (j != (i - 1) && ips[j] == ips[j + 1]) + continue; + + xfs_iunlock(ips[j], lock_mode); + } - if ((attempts % 5) == 0) { - delay(1); /* Don't just spin the CPU */ + if ((attempts % 5) == 0) { + delay(1); /* Don't just spin the CPU */ #ifdef DEBUG - xfs_lock_delays++; + xfs_lock_delays++; #endif - } - i = 0; - try_lock = 0; - goto again; - } - } else { - xfs_ilock(ips[i], xfs_lock_inumorder(lock_mode, i)); } + i = 0; + try_lock = 0; + goto again; } #ifdef DEBUG @@ -2615,19 +2602,22 @@ xfs_remove( /* * Enter all inodes for a rename transaction into a sorted array. */ +#define __XFS_SORT_INODES 5 STATIC void xfs_sort_for_rename( - xfs_inode_t *dp1, /* in: old (source) directory inode */ - xfs_inode_t *dp2, /* in: new (target) directory inode */ - xfs_inode_t *ip1, /* in: inode of old entry */ - xfs_inode_t *ip2, /* in: inode of new entry, if it - already exists, NULL otherwise. */ - xfs_inode_t **i_tab,/* out: array of inode returned, sorted */ - int *num_inodes) /* out: number of inodes in array */ + struct xfs_inode *dp1, /* in: old (source) directory inode */ + struct xfs_inode *dp2, /* in: new (target) directory inode */ + struct xfs_inode *ip1, /* in: inode of old entry */ + struct xfs_inode *ip2, /* in: inode of new entry */ + struct xfs_inode *wip, /* in: whiteout inode */ + struct xfs_inode **i_tab,/* out: sorted array of inodes */ + int *num_inodes) /* in/out: inodes in array */ { - xfs_inode_t *temp; int i, j; + ASSERT(*num_inodes == __XFS_SORT_INODES); + memset(i_tab, 0, *num_inodes * sizeof(struct xfs_inode *)); + /* * i_tab contains a list of pointers to inodes. We initialize * the table here & we'll sort it. We will then use it to @@ -2635,25 +2625,24 @@ xfs_sort_for_rename( * * Note that the table may contain duplicates. e.g., dp1 == dp2. */ - i_tab[0] = dp1; - i_tab[1] = dp2; - i_tab[2] = ip1; - if (ip2) { - *num_inodes = 4; - i_tab[3] = ip2; - } else { - *num_inodes = 3; - i_tab[3] = NULL; - } + i = 0; + i_tab[i++] = dp1; + i_tab[i++] = dp2; + i_tab[i++] = ip1; + if (ip2) + i_tab[i++] = ip2; + if (wip) + i_tab[i++] = wip; + *num_inodes = i; /* * Sort the elements via bubble sort. (Remember, there are at - * most 4 elements to sort, so this is adequate.) + * most 5 elements to sort, so this is adequate.) */ for (i = 0; i < *num_inodes; i++) { for (j = 1; j < *num_inodes; j++) { if (i_tab[j]->i_ino < i_tab[j-1]->i_ino) { - temp = i_tab[j]; + struct xfs_inode *temp = i_tab[j]; i_tab[j] = i_tab[j-1]; i_tab[j-1] = temp; } @@ -2801,16 +2790,16 @@ xfs_rename( xfs_fsblock_t first_block; int cancel_flags; int committed; - xfs_inode_t *inodes[4]; + xfs_inode_t *inodes[__XFS_SORT_INODES]; + int num_inodes = __XFS_SORT_INODES; int spaceres; - int num_inodes; trace_xfs_rename(src_dp, target_dp, src_name, target_name); new_parent = (src_dp != target_dp); src_is_directory = S_ISDIR(src_ip->i_d.di_mode); - xfs_sort_for_rename(src_dp, target_dp, src_ip, target_ip, + xfs_sort_for_rename(src_dp, target_dp, src_ip, target_ip, NULL, inodes, &num_inodes); xfs_bmap_init(&free_list, &first_block); |
