From: "Darrick J. Wong" <djwong@kernel.org>
To: djwong@kernel.org, chandan.babu@oracle.com, chandanrlinux@gmail.com
Cc: linux-xfs@vger.kernel.org
Subject: [PATCH 07/14] xfs: support dynamic btree cursor heights
Date: Fri, 17 Sep 2021 18:29:48 -0700 [thread overview]
Message-ID: <163192858823.416199.17720760425094444911.stgit@magnolia> (raw)
In-Reply-To: <163192854958.416199.3396890438240296942.stgit@magnolia>
From: Darrick J. Wong <djwong@kernel.org>
Split out the btree level information into a separate struct and put it
at the end of the cursor structure as a VLA. The realtime rmap btree
(which is rooted in an inode) will require the ability to support many
more levels than a per-AG btree cursor, which means that we're going to
create two btree cursor caches to conserve memory for the more common
case.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
---
fs/xfs/libxfs/xfs_alloc.c | 6 +-
fs/xfs/libxfs/xfs_bmap.c | 10 +--
fs/xfs/libxfs/xfs_btree.c | 154 +++++++++++++++++++++++----------------------
fs/xfs/libxfs/xfs_btree.h | 28 ++++++--
fs/xfs/scrub/bitmap.c | 16 ++---
fs/xfs/scrub/bmap.c | 2 -
fs/xfs/scrub/btree.c | 40 ++++++------
fs/xfs/scrub/trace.c | 7 +-
fs/xfs/scrub/trace.h | 10 +--
fs/xfs/xfs_super.c | 2 -
fs/xfs/xfs_trace.h | 2 -
11 files changed, 147 insertions(+), 130 deletions(-)
diff --git a/fs/xfs/libxfs/xfs_alloc.c b/fs/xfs/libxfs/xfs_alloc.c
index 35fb1dd3be95..55c5adc9b54e 100644
--- a/fs/xfs/libxfs/xfs_alloc.c
+++ b/fs/xfs/libxfs/xfs_alloc.c
@@ -488,8 +488,8 @@ xfs_alloc_fixup_trees(
struct xfs_btree_block *bnoblock;
struct xfs_btree_block *cntblock;
- bnoblock = XFS_BUF_TO_BLOCK(bno_cur->bc_bufs[0]);
- cntblock = XFS_BUF_TO_BLOCK(cnt_cur->bc_bufs[0]);
+ bnoblock = XFS_BUF_TO_BLOCK(bno_cur->bc_levels[0].bp);
+ cntblock = XFS_BUF_TO_BLOCK(cnt_cur->bc_levels[0].bp);
if (XFS_IS_CORRUPT(mp,
bnoblock->bb_numrecs !=
@@ -1512,7 +1512,7 @@ xfs_alloc_ag_vextent_lastblock(
* than minlen.
*/
if (*len || args->alignment > 1) {
- acur->cnt->bc_ptrs[0] = 1;
+ acur->cnt->bc_levels[0].ptr = 1;
do {
error = xfs_alloc_get_rec(acur->cnt, bno, len, &i);
if (error)
diff --git a/fs/xfs/libxfs/xfs_bmap.c b/fs/xfs/libxfs/xfs_bmap.c
index 499c977cbf56..644b956301b6 100644
--- a/fs/xfs/libxfs/xfs_bmap.c
+++ b/fs/xfs/libxfs/xfs_bmap.c
@@ -240,10 +240,10 @@ xfs_bmap_get_bp(
return NULL;
for (i = 0; i < XFS_BTREE_MAXLEVELS; i++) {
- if (!cur->bc_bufs[i])
+ if (!cur->bc_levels[i].bp)
break;
- if (xfs_buf_daddr(cur->bc_bufs[i]) == bno)
- return cur->bc_bufs[i];
+ if (xfs_buf_daddr(cur->bc_levels[i].bp) == bno)
+ return cur->bc_levels[i].bp;
}
/* Chase down all the log items to see if the bp is there */
@@ -629,8 +629,8 @@ xfs_bmap_btree_to_extents(
ip->i_nblocks--;
xfs_trans_mod_dquot_byino(tp, ip, XFS_TRANS_DQ_BCOUNT, -1L);
xfs_trans_binval(tp, cbp);
- if (cur->bc_bufs[0] == cbp)
- cur->bc_bufs[0] = NULL;
+ if (cur->bc_levels[0].bp == cbp)
+ cur->bc_levels[0].bp = NULL;
xfs_iroot_realloc(ip, -1, whichfork);
ASSERT(ifp->if_broot == NULL);
ifp->if_format = XFS_DINODE_FMT_EXTENTS;
diff --git a/fs/xfs/libxfs/xfs_btree.c b/fs/xfs/libxfs/xfs_btree.c
index bc4e49f0456a..93fb50516bc2 100644
--- a/fs/xfs/libxfs/xfs_btree.c
+++ b/fs/xfs/libxfs/xfs_btree.c
@@ -367,8 +367,8 @@ xfs_btree_del_cursor(
* way we won't have initialized all the entries down to 0.
*/
for (i = 0; i < cur->bc_nlevels; i++) {
- if (cur->bc_bufs[i])
- xfs_trans_brelse(cur->bc_tp, cur->bc_bufs[i]);
+ if (cur->bc_levels[i].bp)
+ xfs_trans_brelse(cur->bc_tp, cur->bc_levels[i].bp);
else if (!error)
break;
}
@@ -415,9 +415,9 @@ xfs_btree_dup_cursor(
* For each level current, re-get the buffer and copy the ptr value.
*/
for (i = 0; i < new->bc_nlevels; i++) {
- new->bc_ptrs[i] = cur->bc_ptrs[i];
- new->bc_ra[i] = cur->bc_ra[i];
- bp = cur->bc_bufs[i];
+ new->bc_levels[i].ptr = cur->bc_levels[i].ptr;
+ new->bc_levels[i].ra = cur->bc_levels[i].ra;
+ bp = cur->bc_levels[i].bp;
if (bp) {
error = xfs_trans_read_buf(mp, tp, mp->m_ddev_targp,
xfs_buf_daddr(bp), mp->m_bsize,
@@ -429,7 +429,7 @@ xfs_btree_dup_cursor(
return error;
}
}
- new->bc_bufs[i] = bp;
+ new->bc_levels[i].bp = bp;
}
*ncur = new;
return 0;
@@ -681,7 +681,7 @@ xfs_btree_get_block(
return xfs_btree_get_iroot(cur);
}
- *bpp = cur->bc_bufs[level];
+ *bpp = cur->bc_levels[level].bp;
return XFS_BUF_TO_BLOCK(*bpp);
}
@@ -711,7 +711,7 @@ xfs_btree_firstrec(
/*
* Set the ptr value to 1, that's the first record/key.
*/
- cur->bc_ptrs[level] = 1;
+ cur->bc_levels[level].ptr = 1;
return 1;
}
@@ -741,7 +741,7 @@ xfs_btree_lastrec(
/*
* Set the ptr value to numrecs, that's the last record/key.
*/
- cur->bc_ptrs[level] = be16_to_cpu(block->bb_numrecs);
+ cur->bc_levels[level].ptr = be16_to_cpu(block->bb_numrecs);
return 1;
}
@@ -922,11 +922,11 @@ xfs_btree_readahead(
(lev == cur->bc_nlevels - 1))
return 0;
- if ((cur->bc_ra[lev] | lr) == cur->bc_ra[lev])
+ if ((cur->bc_levels[lev].ra | lr) == cur->bc_levels[lev].ra)
return 0;
- cur->bc_ra[lev] |= lr;
- block = XFS_BUF_TO_BLOCK(cur->bc_bufs[lev]);
+ cur->bc_levels[lev].ra |= lr;
+ block = XFS_BUF_TO_BLOCK(cur->bc_levels[lev].bp);
if (cur->bc_flags & XFS_BTREE_LONG_PTRS)
return xfs_btree_readahead_lblock(cur, lr, block);
@@ -991,22 +991,22 @@ xfs_btree_setbuf(
{
struct xfs_btree_block *b; /* btree block */
- if (cur->bc_bufs[lev])
- xfs_trans_brelse(cur->bc_tp, cur->bc_bufs[lev]);
- cur->bc_bufs[lev] = bp;
- cur->bc_ra[lev] = 0;
+ if (cur->bc_levels[lev].bp)
+ xfs_trans_brelse(cur->bc_tp, cur->bc_levels[lev].bp);
+ cur->bc_levels[lev].bp = bp;
+ cur->bc_levels[lev].ra = 0;
b = XFS_BUF_TO_BLOCK(bp);
if (cur->bc_flags & XFS_BTREE_LONG_PTRS) {
if (b->bb_u.l.bb_leftsib == cpu_to_be64(NULLFSBLOCK))
- cur->bc_ra[lev] |= XFS_BTCUR_LEFTRA;
+ cur->bc_levels[lev].ra |= XFS_BTCUR_LEFTRA;
if (b->bb_u.l.bb_rightsib == cpu_to_be64(NULLFSBLOCK))
- cur->bc_ra[lev] |= XFS_BTCUR_RIGHTRA;
+ cur->bc_levels[lev].ra |= XFS_BTCUR_RIGHTRA;
} else {
if (b->bb_u.s.bb_leftsib == cpu_to_be32(NULLAGBLOCK))
- cur->bc_ra[lev] |= XFS_BTCUR_LEFTRA;
+ cur->bc_levels[lev].ra |= XFS_BTCUR_LEFTRA;
if (b->bb_u.s.bb_rightsib == cpu_to_be32(NULLAGBLOCK))
- cur->bc_ra[lev] |= XFS_BTCUR_RIGHTRA;
+ cur->bc_levels[lev].ra |= XFS_BTCUR_RIGHTRA;
}
}
@@ -1548,7 +1548,7 @@ xfs_btree_increment(
#endif
/* We're done if we remain in the block after the increment. */
- if (++cur->bc_ptrs[level] <= xfs_btree_get_numrecs(block))
+ if (++cur->bc_levels[level].ptr <= xfs_btree_get_numrecs(block))
goto out1;
/* Fail if we just went off the right edge of the tree. */
@@ -1571,7 +1571,7 @@ xfs_btree_increment(
goto error0;
#endif
- if (++cur->bc_ptrs[lev] <= xfs_btree_get_numrecs(block))
+ if (++cur->bc_levels[lev].ptr <= xfs_btree_get_numrecs(block))
break;
/* Read-ahead the right block for the next loop. */
@@ -1598,14 +1598,14 @@ xfs_btree_increment(
for (block = xfs_btree_get_block(cur, lev, &bp); lev > level; ) {
union xfs_btree_ptr *ptrp;
- ptrp = xfs_btree_ptr_addr(cur, cur->bc_ptrs[lev], block);
+ ptrp = xfs_btree_ptr_addr(cur, cur->bc_levels[lev].ptr, block);
--lev;
error = xfs_btree_read_buf_block(cur, ptrp, 0, &block, &bp);
if (error)
goto error0;
xfs_btree_setbuf(cur, lev, bp);
- cur->bc_ptrs[lev] = 1;
+ cur->bc_levels[lev].ptr = 1;
}
out1:
*stat = 1;
@@ -1641,7 +1641,7 @@ xfs_btree_decrement(
xfs_btree_readahead(cur, level, XFS_BTCUR_LEFTRA);
/* We're done if we remain in the block after the decrement. */
- if (--cur->bc_ptrs[level] > 0)
+ if (--cur->bc_levels[level].ptr > 0)
goto out1;
/* Get a pointer to the btree block. */
@@ -1665,7 +1665,7 @@ xfs_btree_decrement(
* Stop when we don't go off the left edge of a block.
*/
for (lev = level + 1; lev < cur->bc_nlevels; lev++) {
- if (--cur->bc_ptrs[lev] > 0)
+ if (--cur->bc_levels[lev].ptr > 0)
break;
/* Read-ahead the left block for the next loop. */
xfs_btree_readahead(cur, lev, XFS_BTCUR_LEFTRA);
@@ -1691,13 +1691,13 @@ xfs_btree_decrement(
for (block = xfs_btree_get_block(cur, lev, &bp); lev > level; ) {
union xfs_btree_ptr *ptrp;
- ptrp = xfs_btree_ptr_addr(cur, cur->bc_ptrs[lev], block);
+ ptrp = xfs_btree_ptr_addr(cur, cur->bc_levels[lev].ptr, block);
--lev;
error = xfs_btree_read_buf_block(cur, ptrp, 0, &block, &bp);
if (error)
goto error0;
xfs_btree_setbuf(cur, lev, bp);
- cur->bc_ptrs[lev] = xfs_btree_get_numrecs(block);
+ cur->bc_levels[lev].ptr = xfs_btree_get_numrecs(block);
}
out1:
*stat = 1;
@@ -1735,7 +1735,7 @@ xfs_btree_lookup_get_block(
*
* Otherwise throw it away and get a new one.
*/
- bp = cur->bc_bufs[level];
+ bp = cur->bc_levels[level].bp;
error = xfs_btree_ptr_to_daddr(cur, pp, &daddr);
if (error)
return error;
@@ -1864,7 +1864,7 @@ xfs_btree_lookup(
return -EFSCORRUPTED;
}
- cur->bc_ptrs[0] = dir != XFS_LOOKUP_LE;
+ cur->bc_levels[0].ptr = dir != XFS_LOOKUP_LE;
*stat = 0;
return 0;
}
@@ -1916,7 +1916,7 @@ xfs_btree_lookup(
if (error)
goto error0;
- cur->bc_ptrs[level] = keyno;
+ cur->bc_levels[level].ptr = keyno;
}
}
@@ -1933,7 +1933,7 @@ xfs_btree_lookup(
!xfs_btree_ptr_is_null(cur, &ptr)) {
int i;
- cur->bc_ptrs[0] = keyno;
+ cur->bc_levels[0].ptr = keyno;
error = xfs_btree_increment(cur, 0, &i);
if (error)
goto error0;
@@ -1944,7 +1944,7 @@ xfs_btree_lookup(
}
} else if (dir == XFS_LOOKUP_LE && diff > 0)
keyno--;
- cur->bc_ptrs[0] = keyno;
+ cur->bc_levels[0].ptr = keyno;
/* Return if we succeeded or not. */
if (keyno == 0 || keyno > xfs_btree_get_numrecs(block))
@@ -2104,7 +2104,7 @@ __xfs_btree_updkeys(
if (error)
return error;
#endif
- ptr = cur->bc_ptrs[level];
+ ptr = cur->bc_levels[level].ptr;
nlkey = xfs_btree_key_addr(cur, ptr, block);
nhkey = xfs_btree_high_key_addr(cur, ptr, block);
if (!force_all &&
@@ -2171,7 +2171,7 @@ xfs_btree_update_keys(
if (error)
return error;
#endif
- ptr = cur->bc_ptrs[level];
+ ptr = cur->bc_levels[level].ptr;
kp = xfs_btree_key_addr(cur, ptr, block);
xfs_btree_copy_keys(cur, kp, &key, 1);
xfs_btree_log_keys(cur, bp, ptr, ptr);
@@ -2205,7 +2205,7 @@ xfs_btree_update(
goto error0;
#endif
/* Get the address of the rec to be updated. */
- ptr = cur->bc_ptrs[0];
+ ptr = cur->bc_levels[0].ptr;
rp = xfs_btree_rec_addr(cur, ptr, block);
/* Fill in the new contents and log them. */
@@ -2280,7 +2280,7 @@ xfs_btree_lshift(
* If the cursor entry is the one that would be moved, don't
* do it... it's too complicated.
*/
- if (cur->bc_ptrs[level] <= 1)
+ if (cur->bc_levels[level].ptr <= 1)
goto out0;
/* Set up the left neighbor as "left". */
@@ -2414,7 +2414,7 @@ xfs_btree_lshift(
goto error0;
/* Slide the cursor value left one. */
- cur->bc_ptrs[level]--;
+ cur->bc_levels[level].ptr--;
*stat = 1;
return 0;
@@ -2476,7 +2476,7 @@ xfs_btree_rshift(
* do it... it's too complicated.
*/
lrecs = xfs_btree_get_numrecs(left);
- if (cur->bc_ptrs[level] >= lrecs)
+ if (cur->bc_levels[level].ptr >= lrecs)
goto out0;
/* Set up the right neighbor as "right". */
@@ -2664,7 +2664,7 @@ __xfs_btree_split(
*/
lrecs = xfs_btree_get_numrecs(left);
rrecs = lrecs / 2;
- if ((lrecs & 1) && cur->bc_ptrs[level] <= rrecs + 1)
+ if ((lrecs & 1) && cur->bc_levels[level].ptr <= rrecs + 1)
rrecs++;
src_index = (lrecs - rrecs + 1);
@@ -2760,9 +2760,9 @@ __xfs_btree_split(
* If it's just pointing past the last entry in left, then we'll
* insert there, so don't change anything in that case.
*/
- if (cur->bc_ptrs[level] > lrecs + 1) {
+ if (cur->bc_levels[level].ptr > lrecs + 1) {
xfs_btree_setbuf(cur, level, rbp);
- cur->bc_ptrs[level] -= lrecs;
+ cur->bc_levels[level].ptr -= lrecs;
}
/*
* If there are more levels, we'll need another cursor which refers
@@ -2772,7 +2772,7 @@ __xfs_btree_split(
error = xfs_btree_dup_cursor(cur, curp);
if (error)
goto error0;
- (*curp)->bc_ptrs[level + 1]++;
+ (*curp)->bc_levels[level + 1].ptr++;
}
*ptrp = rptr;
*stat = 1;
@@ -2934,7 +2934,7 @@ xfs_btree_new_iroot(
xfs_btree_set_numrecs(block, 1);
cur->bc_nlevels++;
ASSERT(cur->bc_nlevels <= XFS_BTREE_MAXLEVELS);
- cur->bc_ptrs[level + 1] = 1;
+ cur->bc_levels[level + 1].ptr = 1;
kp = xfs_btree_key_addr(cur, 1, block);
ckp = xfs_btree_key_addr(cur, 1, cblock);
@@ -3095,7 +3095,7 @@ xfs_btree_new_root(
/* Fix up the cursor. */
xfs_btree_setbuf(cur, cur->bc_nlevels, nbp);
- cur->bc_ptrs[cur->bc_nlevels] = nptr;
+ cur->bc_levels[cur->bc_nlevels].ptr = nptr;
cur->bc_nlevels++;
ASSERT(cur->bc_nlevels <= XFS_BTREE_MAXLEVELS);
*stat = 1;
@@ -3154,7 +3154,7 @@ xfs_btree_make_block_unfull(
return error;
if (*stat) {
- *oindex = *index = cur->bc_ptrs[level];
+ *oindex = *index = cur->bc_levels[level].ptr;
return 0;
}
@@ -3169,7 +3169,7 @@ xfs_btree_make_block_unfull(
return error;
- *index = cur->bc_ptrs[level];
+ *index = cur->bc_levels[level].ptr;
return 0;
}
@@ -3216,7 +3216,7 @@ xfs_btree_insrec(
}
/* If we're off the left edge, return failure. */
- ptr = cur->bc_ptrs[level];
+ ptr = cur->bc_levels[level].ptr;
if (ptr == 0) {
*stat = 0;
return 0;
@@ -3559,7 +3559,7 @@ xfs_btree_kill_iroot(
if (error)
return error;
- cur->bc_bufs[level - 1] = NULL;
+ cur->bc_levels[level - 1].bp = NULL;
be16_add_cpu(&block->bb_level, -1);
xfs_trans_log_inode(cur->bc_tp, ip,
XFS_ILOG_CORE | xfs_ilog_fbroot(cur->bc_ino.whichfork));
@@ -3592,8 +3592,8 @@ xfs_btree_kill_root(
if (error)
return error;
- cur->bc_bufs[level] = NULL;
- cur->bc_ra[level] = 0;
+ cur->bc_levels[level].bp = NULL;
+ cur->bc_levels[level].ra = 0;
cur->bc_nlevels--;
return 0;
@@ -3652,7 +3652,7 @@ xfs_btree_delrec(
tcur = NULL;
/* Get the index of the entry being deleted, check for nothing there. */
- ptr = cur->bc_ptrs[level];
+ ptr = cur->bc_levels[level].ptr;
if (ptr == 0) {
*stat = 0;
return 0;
@@ -3962,7 +3962,7 @@ xfs_btree_delrec(
xfs_btree_del_cursor(tcur, XFS_BTREE_NOERROR);
tcur = NULL;
if (level == 0)
- cur->bc_ptrs[0]++;
+ cur->bc_levels[0].ptr++;
*stat = 1;
return 0;
@@ -4099,9 +4099,9 @@ xfs_btree_delrec(
* cursor to the left block, and fix up the index.
*/
if (bp != lbp) {
- cur->bc_bufs[level] = lbp;
- cur->bc_ptrs[level] += lrecs;
- cur->bc_ra[level] = 0;
+ cur->bc_levels[level].bp = lbp;
+ cur->bc_levels[level].ptr += lrecs;
+ cur->bc_levels[level].ra = 0;
}
/*
* If we joined with the right neighbor and there's a level above
@@ -4121,11 +4121,11 @@ xfs_btree_delrec(
* We can't use decrement because it would change the next level up.
*/
if (level > 0)
- cur->bc_ptrs[level]--;
+ cur->bc_levels[level].ptr--;
/*
* We combined blocks, so we have to update the parent keys if the
- * btree supports overlapped intervals. However, bc_ptrs[level + 1]
+ * btree supports overlapped intervals. However, bc_levels[level + 1].ptr
* points to the old block so that the caller knows which record to
* delete. Therefore, the caller must be savvy enough to call updkeys
* for us if we return stat == 2. The other exit points from this
@@ -4184,7 +4184,7 @@ xfs_btree_delete(
if (i == 0) {
for (level = 1; level < cur->bc_nlevels; level++) {
- if (cur->bc_ptrs[level] == 0) {
+ if (cur->bc_levels[level].ptr == 0) {
error = xfs_btree_decrement(cur, level, &i);
if (error)
goto error0;
@@ -4215,7 +4215,7 @@ xfs_btree_get_rec(
int error; /* error return value */
#endif
- ptr = cur->bc_ptrs[0];
+ ptr = cur->bc_levels[0].ptr;
block = xfs_btree_get_block(cur, 0, &bp);
#ifdef DEBUG
@@ -4663,23 +4663,23 @@ xfs_btree_overlapped_query_range(
if (error)
goto out;
#endif
- cur->bc_ptrs[level] = 1;
+ cur->bc_levels[level].ptr = 1;
while (level < cur->bc_nlevels) {
block = xfs_btree_get_block(cur, level, &bp);
/* End of node, pop back towards the root. */
- if (cur->bc_ptrs[level] > be16_to_cpu(block->bb_numrecs)) {
+ if (cur->bc_levels[level].ptr > be16_to_cpu(block->bb_numrecs)) {
pop_up:
if (level < cur->bc_nlevels - 1)
- cur->bc_ptrs[level + 1]++;
+ cur->bc_levels[level + 1].ptr++;
level++;
continue;
}
if (level == 0) {
/* Handle a leaf node. */
- recp = xfs_btree_rec_addr(cur, cur->bc_ptrs[0], block);
+ recp = xfs_btree_rec_addr(cur, cur->bc_levels[0].ptr, block);
cur->bc_ops->init_high_key_from_rec(&rec_hkey, recp);
ldiff = cur->bc_ops->diff_two_keys(cur, &rec_hkey,
@@ -4702,14 +4702,14 @@ xfs_btree_overlapped_query_range(
/* Record is larger than high key; pop. */
goto pop_up;
}
- cur->bc_ptrs[level]++;
+ cur->bc_levels[level].ptr++;
continue;
}
/* Handle an internal node. */
- lkp = xfs_btree_key_addr(cur, cur->bc_ptrs[level], block);
- hkp = xfs_btree_high_key_addr(cur, cur->bc_ptrs[level], block);
- pp = xfs_btree_ptr_addr(cur, cur->bc_ptrs[level], block);
+ lkp = xfs_btree_key_addr(cur, cur->bc_levels[level].ptr, block);
+ hkp = xfs_btree_high_key_addr(cur, cur->bc_levels[level].ptr, block);
+ pp = xfs_btree_ptr_addr(cur, cur->bc_levels[level].ptr, block);
ldiff = cur->bc_ops->diff_two_keys(cur, hkp, low_key);
hdiff = cur->bc_ops->diff_two_keys(cur, high_key, lkp);
@@ -4732,13 +4732,13 @@ xfs_btree_overlapped_query_range(
if (error)
goto out;
#endif
- cur->bc_ptrs[level] = 1;
+ cur->bc_levels[level].ptr = 1;
continue;
} else if (hdiff < 0) {
/* The low key is larger than the upper range; pop. */
goto pop_up;
}
- cur->bc_ptrs[level]++;
+ cur->bc_levels[level].ptr++;
}
out:
@@ -4749,13 +4749,13 @@ xfs_btree_overlapped_query_range(
* with a zero-results range query, so release the buffers if we
* failed to return any results.
*/
- if (cur->bc_bufs[0] == NULL) {
+ if (cur->bc_levels[0].bp == NULL) {
for (i = 0; i < cur->bc_nlevels; i++) {
- if (cur->bc_bufs[i]) {
- xfs_trans_brelse(cur->bc_tp, cur->bc_bufs[i]);
- cur->bc_bufs[i] = NULL;
- cur->bc_ptrs[i] = 0;
- cur->bc_ra[i] = 0;
+ if (cur->bc_levels[i].bp) {
+ xfs_trans_brelse(cur->bc_tp, cur->bc_levels[i].bp);
+ cur->bc_levels[i].bp = NULL;
+ cur->bc_levels[i].ptr = 0;
+ cur->bc_levels[i].ra = 0;
}
}
}
@@ -4917,7 +4917,7 @@ xfs_btree_has_more_records(
block = xfs_btree_get_block(cur, 0, &bp);
/* There are still records in this block. */
- if (cur->bc_ptrs[0] < xfs_btree_get_numrecs(block))
+ if (cur->bc_levels[0].ptr < xfs_btree_get_numrecs(block))
return true;
/* There are more record blocks. */
diff --git a/fs/xfs/libxfs/xfs_btree.h b/fs/xfs/libxfs/xfs_btree.h
index 513ade4a89f8..827c44bf24dc 100644
--- a/fs/xfs/libxfs/xfs_btree.h
+++ b/fs/xfs/libxfs/xfs_btree.h
@@ -212,6 +212,19 @@ struct xfs_btree_cur_ino {
#define XFS_BTCUR_BMBT_INVALID_OWNER (1 << 1)
};
+struct xfs_btree_level {
+ /* buffer pointer */
+ struct xfs_buf *bp;
+
+ /* key/record number */
+ unsigned int ptr;
+
+ /* readahead info */
+#define XFS_BTCUR_LEFTRA 1 /* left sibling has been read-ahead */
+#define XFS_BTCUR_RIGHTRA 2 /* right sibling has been read-ahead */
+ uint8_t ra;
+};
+
/*
* Btree cursor structure.
* This collects all information needed by the btree code in one place.
@@ -223,11 +236,6 @@ struct xfs_btree_cur
const struct xfs_btree_ops *bc_ops;
uint bc_flags; /* btree features - below */
union xfs_btree_irec bc_rec; /* current insert/search record value */
- struct xfs_buf *bc_bufs[XFS_BTREE_MAXLEVELS]; /* buf ptr per level */
- int bc_ptrs[XFS_BTREE_MAXLEVELS]; /* key/record # */
- uint8_t bc_ra[XFS_BTREE_MAXLEVELS]; /* readahead bits */
-#define XFS_BTCUR_LEFTRA 1 /* left sibling has been read-ahead */
-#define XFS_BTCUR_RIGHTRA 2 /* right sibling has been read-ahead */
uint8_t bc_nlevels; /* number of levels in the tree */
uint8_t bc_blocklog; /* log2(blocksize) of btree blocks */
xfs_btnum_t bc_btnum; /* identifies which btree type */
@@ -243,8 +251,17 @@ struct xfs_btree_cur
struct xfs_btree_cur_ag bc_ag;
struct xfs_btree_cur_ino bc_ino;
};
+
+ /* Must be at the end of the struct! */
+ struct xfs_btree_level bc_levels[];
};
+static inline size_t xfs_btree_cur_sizeof(unsigned int nlevels)
+{
+ return sizeof(struct xfs_btree_cur) +
+ sizeof(struct xfs_btree_level) * (nlevels);
+}
+
/* cursor flags */
#define XFS_BTREE_LONG_PTRS (1<<0) /* pointers are 64bits long */
#define XFS_BTREE_ROOT_IN_INODE (1<<1) /* root may be variable size */
@@ -258,7 +275,6 @@ struct xfs_btree_cur
*/
#define XFS_BTREE_STAGING (1<<5)
-
#define XFS_BTREE_NOERROR 0
#define XFS_BTREE_ERROR 1
diff --git a/fs/xfs/scrub/bitmap.c b/fs/xfs/scrub/bitmap.c
index d6d24c866bc4..b8b8e871e3b7 100644
--- a/fs/xfs/scrub/bitmap.c
+++ b/fs/xfs/scrub/bitmap.c
@@ -222,20 +222,20 @@ xbitmap_disunion(
* 1 2 3
*
* Pretend for this example that each leaf block has 100 btree records. For
- * the first btree record, we'll observe that bc_ptrs[0] == 1, so we record
- * that we saw block 1. Then we observe that bc_ptrs[1] == 1, so we record
+ * the first btree record, we'll observe that bc_levels[0].ptr == 1, so we record
+ * that we saw block 1. Then we observe that bc_levels[1].ptr == 1, so we record
* block 4. The list is [1, 4].
*
- * For the second btree record, we see that bc_ptrs[0] == 2, so we exit the
+ * For the second btree record, we see that bc_levels[0].ptr == 2, so we exit the
* loop. The list remains [1, 4].
*
* For the 101st btree record, we've moved onto leaf block 2. Now
- * bc_ptrs[0] == 1 again, so we record that we saw block 2. We see that
- * bc_ptrs[1] == 2, so we exit the loop. The list is now [1, 4, 2].
+ * bc_levels[0].ptr == 1 again, so we record that we saw block 2. We see that
+ * bc_levels[1].ptr == 2, so we exit the loop. The list is now [1, 4, 2].
*
- * For the 102nd record, bc_ptrs[0] == 2, so we continue.
+ * For the 102nd record, bc_levels[0].ptr == 2, so we continue.
*
- * For the 201st record, we've moved on to leaf block 3. bc_ptrs[0] == 1, so
+ * For the 201st record, we've moved on to leaf block 3. bc_levels[0].ptr == 1, so
* we add 3 to the list. Now it is [1, 4, 2, 3].
*
* For the 300th record we just exit, with the list being [1, 4, 2, 3].
@@ -256,7 +256,7 @@ xbitmap_set_btcur_path(
int i;
int error;
- for (i = 0; i < cur->bc_nlevels && cur->bc_ptrs[i] == 1; i++) {
+ for (i = 0; i < cur->bc_nlevels && cur->bc_levels[i].ptr == 1; i++) {
xfs_btree_get_block(cur, i, &bp);
if (!bp)
continue;
diff --git a/fs/xfs/scrub/bmap.c b/fs/xfs/scrub/bmap.c
index 017da9ceaee9..a4cbbc346f60 100644
--- a/fs/xfs/scrub/bmap.c
+++ b/fs/xfs/scrub/bmap.c
@@ -402,7 +402,7 @@ xchk_bmapbt_rec(
* the root since the verifiers don't do that.
*/
if (xfs_has_crc(bs->cur->bc_mp) &&
- bs->cur->bc_ptrs[0] == 1) {
+ bs->cur->bc_levels[0].ptr == 1) {
for (i = 0; i < bs->cur->bc_nlevels - 1; i++) {
block = xfs_btree_get_block(bs->cur, i, &bp);
owner = be64_to_cpu(block->bb_u.l.bb_owner);
diff --git a/fs/xfs/scrub/btree.c b/fs/xfs/scrub/btree.c
index 7b7762ae22e5..5a453ce151ed 100644
--- a/fs/xfs/scrub/btree.c
+++ b/fs/xfs/scrub/btree.c
@@ -136,7 +136,7 @@ xchk_btree_rec(
struct xfs_buf *bp;
block = xfs_btree_get_block(cur, 0, &bp);
- rec = xfs_btree_rec_addr(cur, cur->bc_ptrs[0], block);
+ rec = xfs_btree_rec_addr(cur, cur->bc_levels[0].ptr, block);
trace_xchk_btree_rec(bs->sc, cur, 0);
@@ -153,7 +153,7 @@ xchk_btree_rec(
/* Is this at least as large as the parent low key? */
cur->bc_ops->init_key_from_rec(&key, rec);
keyblock = xfs_btree_get_block(cur, 1, &bp);
- keyp = xfs_btree_key_addr(cur, cur->bc_ptrs[1], keyblock);
+ keyp = xfs_btree_key_addr(cur, cur->bc_levels[1].ptr, keyblock);
if (cur->bc_ops->diff_two_keys(cur, &key, keyp) < 0)
xchk_btree_set_corrupt(bs->sc, cur, 1);
@@ -162,7 +162,7 @@ xchk_btree_rec(
/* Is this no larger than the parent high key? */
cur->bc_ops->init_high_key_from_rec(&hkey, rec);
- keyp = xfs_btree_high_key_addr(cur, cur->bc_ptrs[1], keyblock);
+ keyp = xfs_btree_high_key_addr(cur, cur->bc_levels[1].ptr, keyblock);
if (cur->bc_ops->diff_two_keys(cur, keyp, &hkey) < 0)
xchk_btree_set_corrupt(bs->sc, cur, 1);
}
@@ -184,7 +184,7 @@ xchk_btree_key(
struct xfs_buf *bp;
block = xfs_btree_get_block(cur, level, &bp);
- key = xfs_btree_key_addr(cur, cur->bc_ptrs[level], block);
+ key = xfs_btree_key_addr(cur, cur->bc_levels[level].ptr, block);
trace_xchk_btree_key(bs->sc, cur, level);
@@ -200,7 +200,7 @@ xchk_btree_key(
/* Is this at least as large as the parent low key? */
keyblock = xfs_btree_get_block(cur, level + 1, &bp);
- keyp = xfs_btree_key_addr(cur, cur->bc_ptrs[level + 1], keyblock);
+ keyp = xfs_btree_key_addr(cur, cur->bc_levels[level + 1].ptr, keyblock);
if (cur->bc_ops->diff_two_keys(cur, key, keyp) < 0)
xchk_btree_set_corrupt(bs->sc, cur, level);
@@ -208,8 +208,8 @@ xchk_btree_key(
return;
/* Is this no larger than the parent high key? */
- key = xfs_btree_high_key_addr(cur, cur->bc_ptrs[level], block);
- keyp = xfs_btree_high_key_addr(cur, cur->bc_ptrs[level + 1], keyblock);
+ key = xfs_btree_high_key_addr(cur, cur->bc_levels[level].ptr, block);
+ keyp = xfs_btree_high_key_addr(cur, cur->bc_levels[level + 1].ptr, keyblock);
if (cur->bc_ops->diff_two_keys(cur, keyp, key) < 0)
xchk_btree_set_corrupt(bs->sc, cur, level);
}
@@ -292,7 +292,7 @@ xchk_btree_block_check_sibling(
/* Compare upper level pointer to sibling pointer. */
pblock = xfs_btree_get_block(ncur, level + 1, &pbp);
- pp = xfs_btree_ptr_addr(ncur, ncur->bc_ptrs[level + 1], pblock);
+ pp = xfs_btree_ptr_addr(ncur, ncur->bc_levels[level + 1].ptr, pblock);
if (!xchk_btree_ptr_ok(bs, level + 1, pp))
goto out;
if (pbp)
@@ -597,7 +597,7 @@ xchk_btree_block_keys(
/* Obtain the parent's copy of the keys for this block. */
parent_block = xfs_btree_get_block(cur, level + 1, &bp);
- parent_keys = xfs_btree_key_addr(cur, cur->bc_ptrs[level + 1],
+ parent_keys = xfs_btree_key_addr(cur, cur->bc_levels[level + 1].ptr,
parent_block);
if (cur->bc_ops->diff_two_keys(cur, &block_keys, parent_keys) != 0)
@@ -608,7 +608,7 @@ xchk_btree_block_keys(
/* Get high keys */
high_bk = xfs_btree_high_key_from_key(cur, &block_keys);
- high_pk = xfs_btree_high_key_addr(cur, cur->bc_ptrs[level + 1],
+ high_pk = xfs_btree_high_key_addr(cur, cur->bc_levels[level + 1].ptr,
parent_block);
if (cur->bc_ops->diff_two_keys(cur, high_bk, high_pk) != 0)
@@ -672,18 +672,18 @@ xchk_btree(
if (error || !block)
goto out;
- cur->bc_ptrs[level] = 1;
+ cur->bc_levels[level].ptr = 1;
while (level < cur->bc_nlevels) {
block = xfs_btree_get_block(cur, level, &bp);
if (level == 0) {
/* End of leaf, pop back towards the root. */
- if (cur->bc_ptrs[level] >
+ if (cur->bc_levels[level].ptr >
be16_to_cpu(block->bb_numrecs)) {
xchk_btree_block_keys(bs, level, block);
if (level < cur->bc_nlevels - 1)
- cur->bc_ptrs[level + 1]++;
+ cur->bc_levels[level + 1].ptr++;
level++;
continue;
}
@@ -692,7 +692,7 @@ xchk_btree(
xchk_btree_rec(bs);
/* Call out to the record checker. */
- recp = xfs_btree_rec_addr(cur, cur->bc_ptrs[0], block);
+ recp = xfs_btree_rec_addr(cur, cur->bc_levels[0].ptr, block);
error = bs->scrub_rec(bs, recp);
if (error)
break;
@@ -700,15 +700,15 @@ xchk_btree(
(sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT))
break;
- cur->bc_ptrs[level]++;
+ cur->bc_levels[level].ptr++;
continue;
}
/* End of node, pop back towards the root. */
- if (cur->bc_ptrs[level] > be16_to_cpu(block->bb_numrecs)) {
+ if (cur->bc_levels[level].ptr > be16_to_cpu(block->bb_numrecs)) {
xchk_btree_block_keys(bs, level, block);
if (level < cur->bc_nlevels - 1)
- cur->bc_ptrs[level + 1]++;
+ cur->bc_levels[level + 1].ptr++;
level++;
continue;
}
@@ -717,9 +717,9 @@ xchk_btree(
xchk_btree_key(bs, level);
/* Drill another level deeper. */
- pp = xfs_btree_ptr_addr(cur, cur->bc_ptrs[level], block);
+ pp = xfs_btree_ptr_addr(cur, cur->bc_levels[level].ptr, block);
if (!xchk_btree_ptr_ok(bs, level, pp)) {
- cur->bc_ptrs[level]++;
+ cur->bc_levels[level].ptr++;
continue;
}
level--;
@@ -727,7 +727,7 @@ xchk_btree(
if (error || !block)
goto out;
- cur->bc_ptrs[level] = 1;
+ cur->bc_levels[level].ptr = 1;
}
out:
diff --git a/fs/xfs/scrub/trace.c b/fs/xfs/scrub/trace.c
index c0ef53fe6611..816dfc8e5a80 100644
--- a/fs/xfs/scrub/trace.c
+++ b/fs/xfs/scrub/trace.c
@@ -21,10 +21,11 @@ xchk_btree_cur_fsbno(
struct xfs_btree_cur *cur,
int level)
{
- if (level < cur->bc_nlevels && cur->bc_bufs[level])
+ if (level < cur->bc_nlevels && cur->bc_levels[level].bp)
return XFS_DADDR_TO_FSB(cur->bc_mp,
- xfs_buf_daddr(cur->bc_bufs[level]));
- if (level == cur->bc_nlevels - 1 && cur->bc_flags & XFS_BTREE_LONG_PTRS)
+ xfs_buf_daddr(cur->bc_levels[level].bp));
+ else if (level == cur->bc_nlevels - 1 &&
+ cur->bc_flags & XFS_BTREE_LONG_PTRS)
return XFS_INO_TO_FSB(cur->bc_mp, cur->bc_ino.ip->i_ino);
if (!(cur->bc_flags & XFS_BTREE_LONG_PTRS))
return XFS_AGB_TO_FSB(cur->bc_mp, cur->bc_ag.pag->pag_agno, 0);
diff --git a/fs/xfs/scrub/trace.h b/fs/xfs/scrub/trace.h
index a7bbb84f91a7..93ece6df02e3 100644
--- a/fs/xfs/scrub/trace.h
+++ b/fs/xfs/scrub/trace.h
@@ -348,7 +348,7 @@ TRACE_EVENT(xchk_btree_op_error,
__entry->level = level;
__entry->agno = XFS_FSB_TO_AGNO(cur->bc_mp, fsbno);
__entry->bno = XFS_FSB_TO_AGBNO(cur->bc_mp, fsbno);
- __entry->ptr = cur->bc_ptrs[level];
+ __entry->ptr = cur->bc_levels[level].ptr;
__entry->error = error;
__entry->ret_ip = ret_ip;
),
@@ -389,7 +389,7 @@ TRACE_EVENT(xchk_ifork_btree_op_error,
__entry->type = sc->sm->sm_type;
__entry->btnum = cur->bc_btnum;
__entry->level = level;
- __entry->ptr = cur->bc_ptrs[level];
+ __entry->ptr = cur->bc_levels[level].ptr;
__entry->agno = XFS_FSB_TO_AGNO(cur->bc_mp, fsbno);
__entry->bno = XFS_FSB_TO_AGBNO(cur->bc_mp, fsbno);
__entry->error = error;
@@ -431,7 +431,7 @@ TRACE_EVENT(xchk_btree_error,
__entry->level = level;
__entry->agno = XFS_FSB_TO_AGNO(cur->bc_mp, fsbno);
__entry->bno = XFS_FSB_TO_AGBNO(cur->bc_mp, fsbno);
- __entry->ptr = cur->bc_ptrs[level];
+ __entry->ptr = cur->bc_levels[level].ptr;
__entry->ret_ip = ret_ip;
),
TP_printk("dev %d:%d type %s btree %s level %d ptr %d agno 0x%x agbno 0x%x ret_ip %pS",
@@ -471,7 +471,7 @@ TRACE_EVENT(xchk_ifork_btree_error,
__entry->level = level;
__entry->agno = XFS_FSB_TO_AGNO(cur->bc_mp, fsbno);
__entry->bno = XFS_FSB_TO_AGBNO(cur->bc_mp, fsbno);
- __entry->ptr = cur->bc_ptrs[level];
+ __entry->ptr = cur->bc_levels[level].ptr;
__entry->ret_ip = ret_ip;
),
TP_printk("dev %d:%d ino 0x%llx fork %s type %s btree %s level %d ptr %d agno 0x%x agbno 0x%x ret_ip %pS",
@@ -511,7 +511,7 @@ DECLARE_EVENT_CLASS(xchk_sbtree_class,
__entry->bno = XFS_FSB_TO_AGBNO(cur->bc_mp, fsbno);
__entry->level = level;
__entry->nlevels = cur->bc_nlevels;
- __entry->ptr = cur->bc_ptrs[level];
+ __entry->ptr = cur->bc_levels[level].ptr;
),
TP_printk("dev %d:%d type %s btree %s agno 0x%x agbno 0x%x level %d nlevels %d ptr %d",
MAJOR(__entry->dev), MINOR(__entry->dev),
diff --git a/fs/xfs/xfs_super.c b/fs/xfs/xfs_super.c
index c4e0cd1c1c8c..30bae0657343 100644
--- a/fs/xfs/xfs_super.c
+++ b/fs/xfs/xfs_super.c
@@ -1966,7 +1966,7 @@ xfs_init_zones(void)
goto out_destroy_log_ticket_zone;
xfs_btree_cur_zone = kmem_cache_create("xfs_btree_cur",
- sizeof(struct xfs_btree_cur),
+ xfs_btree_cur_sizeof(XFS_BTREE_MAXLEVELS),
0, 0, NULL);
if (!xfs_btree_cur_zone)
goto out_destroy_bmap_free_item_zone;
diff --git a/fs/xfs/xfs_trace.h b/fs/xfs/xfs_trace.h
index 1033a95fbf8e..4a8076ef8cb4 100644
--- a/fs/xfs/xfs_trace.h
+++ b/fs/xfs/xfs_trace.h
@@ -2476,7 +2476,7 @@ DECLARE_EVENT_CLASS(xfs_btree_cur_class,
__entry->btnum = cur->bc_btnum;
__entry->level = level;
__entry->nlevels = cur->bc_nlevels;
- __entry->ptr = cur->bc_ptrs[level];
+ __entry->ptr = cur->bc_levels[level].ptr;
__entry->daddr = bp ? xfs_buf_daddr(bp) : -1;
),
TP_printk("dev %d:%d btree %s level %d/%d ptr %d daddr 0x%llx",
next prev parent reply other threads:[~2021-09-18 1:29 UTC|newest]
Thread overview: 48+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-09-18 1:29 [PATCHSET RFC chandan 00/14] xfs: support dynamic btree cursor height Darrick J. Wong
2021-09-18 1:29 ` [PATCH 01/14] xfs: remove xfs_btree_cur_t typedef Darrick J. Wong
2021-09-20 9:53 ` Chandan Babu R
2021-09-21 8:36 ` Christoph Hellwig
2021-09-18 1:29 ` [PATCH 02/14] xfs: don't allocate scrub contexts on the stack Darrick J. Wong
2021-09-20 9:53 ` Chandan Babu R
2021-09-20 17:39 ` Darrick J. Wong
2021-09-21 8:39 ` Christoph Hellwig
2021-09-18 1:29 ` [PATCH 03/14] xfs: dynamically allocate btree scrub context structure Darrick J. Wong
2021-09-20 9:53 ` Chandan Babu R
2021-09-21 8:43 ` Christoph Hellwig
2021-09-22 16:17 ` Darrick J. Wong
2021-09-18 1:29 ` [PATCH 04/14] xfs: stricter btree height checking when looking for errors Darrick J. Wong
2021-09-20 9:54 ` Chandan Babu R
2021-09-18 1:29 ` [PATCH 05/14] xfs: stricter btree height checking when scanning for btree roots Darrick J. Wong
2021-09-20 9:54 ` Chandan Babu R
2021-09-18 1:29 ` [PATCH 06/14] xfs: check that bc_nlevels never overflows Darrick J. Wong
2021-09-20 9:54 ` Chandan Babu R
2021-09-21 8:44 ` Christoph Hellwig
2021-09-18 1:29 ` Darrick J. Wong [this message]
2021-09-20 9:55 ` [PATCH 07/14] xfs: support dynamic btree cursor heights Chandan Babu R
2021-09-21 8:49 ` Christoph Hellwig
2021-09-18 1:29 ` [PATCH 08/14] xfs: refactor btree cursor allocation function Darrick J. Wong
2021-09-20 9:55 ` Chandan Babu R
2021-09-21 8:53 ` Christoph Hellwig
2021-09-18 1:29 ` [PATCH 09/14] xfs: fix maxlevels comparisons in the btree staging code Darrick J. Wong
2021-09-20 9:55 ` Chandan Babu R
2021-09-21 8:56 ` Christoph Hellwig
2021-09-22 15:59 ` Darrick J. Wong
2021-09-18 1:30 ` [PATCH 10/14] xfs: encode the max btree height in the cursor Darrick J. Wong
2021-09-20 9:55 ` Chandan Babu R
2021-09-21 8:57 ` Christoph Hellwig
2021-09-18 1:30 ` [PATCH 11/14] xfs: dynamically allocate cursors based on maxlevels Darrick J. Wong
2021-09-20 9:56 ` Chandan Babu R
2021-09-20 23:06 ` Dave Chinner
2021-09-20 23:36 ` Dave Chinner
2021-09-21 9:03 ` Christoph Hellwig
2021-09-22 18:55 ` Darrick J. Wong
2021-09-22 17:38 ` Darrick J. Wong
2021-09-22 23:10 ` Dave Chinner
2021-09-23 1:58 ` Darrick J. Wong
2021-09-23 5:56 ` Chandan Babu R
2021-09-18 1:30 ` [PATCH 12/14] xfs: compute actual maximum btree height for critical reservation calculation Darrick J. Wong
2021-09-20 9:56 ` Chandan Babu R
2021-09-18 1:30 ` [PATCH 13/14] xfs: compute the maximum height of the rmap btree when reflink enabled Darrick J. Wong
2021-09-20 9:56 ` Chandan Babu R
2021-09-18 1:30 ` [PATCH 14/14] xfs: kill XFS_BTREE_MAXLEVELS Darrick J. Wong
2021-09-20 9:57 ` Chandan Babu R
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