xfs: clean up xfs_alloc_ag_vextent_exact

Use a goto label to consolidate all block not found cases, and add a
tracepoint for them.  Also clean up a few whitespace issues.

Based on an earlier patch from Dave Chinner.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
This commit is contained in:
Christoph Hellwig 2010-12-10 15:03:57 +00:00 committed by Alex Elder
parent ecff71e677
commit 9f9baab38d
2 changed files with 33 additions and 26 deletions

View File

@ -1422,6 +1422,7 @@ DEFINE_EVENT(xfs_alloc_class, name, \
TP_PROTO(struct xfs_alloc_arg *args), \
TP_ARGS(args))
DEFINE_ALLOC_EVENT(xfs_alloc_exact_done);
DEFINE_ALLOC_EVENT(xfs_alloc_exact_notfound);
DEFINE_ALLOC_EVENT(xfs_alloc_exact_error);
DEFINE_ALLOC_EVENT(xfs_alloc_near_nominleft);
DEFINE_ALLOC_EVENT(xfs_alloc_near_first);

View File

@ -577,61 +577,58 @@ xfs_alloc_ag_vextent_exact(
xfs_extlen_t rlen; /* length of returned extent */
ASSERT(args->alignment == 1);
/*
* Allocate/initialize a cursor for the by-number freespace btree.
*/
bno_cur = xfs_allocbt_init_cursor(args->mp, args->tp, args->agbp,
args->agno, XFS_BTNUM_BNO);
args->agno, XFS_BTNUM_BNO);
/*
* Lookup bno and minlen in the btree (minlen is irrelevant, really).
* Look for the closest free block <= bno, it must contain bno
* if any free block does.
*/
if ((error = xfs_alloc_lookup_le(bno_cur, args->agbno, args->minlen, &i)))
error = xfs_alloc_lookup_le(bno_cur, args->agbno, args->minlen, &i);
if (error)
goto error0;
if (!i) {
/*
* Didn't find it, return null.
*/
xfs_btree_del_cursor(bno_cur, XFS_BTREE_NOERROR);
args->agbno = NULLAGBLOCK;
return 0;
}
if (!i)
goto not_found;
/*
* Grab the freespace record.
*/
if ((error = xfs_alloc_get_rec(bno_cur, &fbno, &flen, &i)))
error = xfs_alloc_get_rec(bno_cur, &fbno, &flen, &i);
if (error)
goto error0;
XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
ASSERT(fbno <= args->agbno);
minend = args->agbno + args->minlen;
maxend = args->agbno + args->maxlen;
fend = fbno + flen;
/*
* Give up if the freespace isn't long enough for the minimum request.
*/
if (fend < minend) {
xfs_btree_del_cursor(bno_cur, XFS_BTREE_NOERROR);
args->agbno = NULLAGBLOCK;
return 0;
}
if (fend < minend)
goto not_found;
/*
* End of extent will be smaller of the freespace end and the
* maximal requested end.
*/
end = XFS_AGBLOCK_MIN(fend, maxend);
/*
*
* Fix the length according to mod and prod if given.
*/
end = XFS_AGBLOCK_MIN(fend, maxend);
args->len = end - args->agbno;
xfs_alloc_fix_len(args);
if (!xfs_alloc_fix_minleft(args)) {
xfs_btree_del_cursor(bno_cur, XFS_BTREE_NOERROR);
return 0;
}
if (!xfs_alloc_fix_minleft(args))
goto not_found;
rlen = args->len;
ASSERT(args->agbno + rlen <= fend);
end = args->agbno + rlen;
/*
* We are allocating agbno for rlen [agbno .. end]
* Allocate/initialize a cursor for the by-size btree.
@ -640,16 +637,25 @@ xfs_alloc_ag_vextent_exact(
args->agno, XFS_BTNUM_CNT);
ASSERT(args->agbno + args->len <=
be32_to_cpu(XFS_BUF_TO_AGF(args->agbp)->agf_length));
if ((error = xfs_alloc_fixup_trees(cnt_cur, bno_cur, fbno, flen,
args->agbno, args->len, XFSA_FIXUP_BNO_OK))) {
error = xfs_alloc_fixup_trees(cnt_cur, bno_cur, fbno, flen, args->agbno,
args->len, XFSA_FIXUP_BNO_OK);
if (error) {
xfs_btree_del_cursor(cnt_cur, XFS_BTREE_ERROR);
goto error0;
}
xfs_btree_del_cursor(bno_cur, XFS_BTREE_NOERROR);
xfs_btree_del_cursor(cnt_cur, XFS_BTREE_NOERROR);
trace_xfs_alloc_exact_done(args);
args->wasfromfl = 0;
trace_xfs_alloc_exact_done(args);
return 0;
not_found:
/* Didn't find it, return null. */
xfs_btree_del_cursor(bno_cur, XFS_BTREE_NOERROR);
args->agbno = NULLAGBLOCK;
trace_xfs_alloc_exact_notfound(args);
return 0;
error0: