bool busy;
unsigned busy_gen = 0;
bool deactivate = false;
+ bool isbnobt = cur->bc_btnum == XFS_BTNUM_BNO;
*new = 0;
* range (i.e., walking backwards looking for a minlen extent).
*/
if (len < args->minlen) {
- deactivate = true;
+ deactivate = !isbnobt;
goto out;
}
if (busy)
acur->busy_gen = busy_gen;
/* deactivate a bnobt cursor outside of locality range */
- if (bnoa < args->min_agbno || bnoa > args->max_agbno)
+ if (bnoa < args->min_agbno || bnoa > args->max_agbno) {
+ deactivate = isbnobt;
goto out;
+ }
if (lena < args->minlen)
goto out;
bnoa, lena, &bnew);
if (bnew == NULLAGBLOCK)
goto out;
- if (diff > acur->diff)
+
+ /*
+ * Deactivate a bnobt cursor with worse locality than the current best.
+ */
+ if (diff > acur->diff) {
+ deactivate = isbnobt;
goto out;
+ }
ASSERT(args->len > acur->len ||
(args->len == acur->len && diff <= acur->diff));
}
/*
- * Search the btree in a given direction via the search cursor and compare
- * the records found against the good extent we've already found.
+ * Search the btree in a given direction and check the records against the good
+ * extent we've already found.
*/
STATIC int
xfs_alloc_find_best_extent(
- struct xfs_alloc_arg *args, /* allocation argument structure */
- struct xfs_btree_cur *gcur, /* good cursor */
- struct xfs_btree_cur *scur, /* searching cursor */
- xfs_agblock_t gdiff, /* difference for search comparison */
- xfs_agblock_t *sbno, /* extent found by search */
- xfs_extlen_t *slen, /* extent length */
- xfs_agblock_t *sbnoa, /* aligned extent found by search */
- xfs_extlen_t *slena, /* aligned extent length */
- int dir) /* 0 = search right, 1 = search left */
+ struct xfs_alloc_arg *args,
+ struct xfs_alloc_cur *acur,
+ struct xfs_btree_cur *cur,
+ bool increment)
{
- xfs_agblock_t new;
- xfs_agblock_t sdiff;
int error;
int i;
- unsigned busy_gen;
-
- /* The good extent is perfect, no need to search. */
- if (!gdiff)
- goto out_use_good;
/*
- * Look until we find a better one, run out of space or run off the end.
+ * Search so long as the cursor is active or we find a better extent.
+ * The cursor is deactivated if it extends beyond the range of the
+ * current allocation candidate.
*/
- do {
- error = xfs_alloc_get_rec(scur, sbno, slen, &i);
+ while (xfs_alloc_cur_active(cur)) {
+ error = xfs_alloc_cur_check(args, acur, cur, &i);
if (error)
- goto error0;
- XFS_WANT_CORRUPTED_GOTO(args->mp, i == 1, error0);
- xfs_alloc_compute_aligned(args, *sbno, *slen,
- sbnoa, slena, &busy_gen);
-
- /*
- * The good extent is closer than this one.
- */
- if (!dir) {
- if (*sbnoa > args->max_agbno)
- goto out_use_good;
- if (*sbnoa >= args->agbno + gdiff)
- goto out_use_good;
- } else {
- if (*sbnoa < args->min_agbno)
- goto out_use_good;
- if (*sbnoa <= args->agbno - gdiff)
- goto out_use_good;
- }
-
- /*
- * Same distance, compare length and pick the best.
- */
- if (*slena >= args->minlen) {
- args->len = XFS_EXTLEN_MIN(*slena, args->maxlen);
- xfs_alloc_fix_len(args);
-
- sdiff = xfs_alloc_compute_diff(args->agbno, args->len,
- args->alignment,
- args->datatype, *sbnoa,
- *slena, &new);
-
- /*
- * Choose closer size and invalidate other cursor.
- */
- if (sdiff < gdiff)
- goto out_use_search;
- goto out_use_good;
- }
+ return error;
+ if (i == 1)
+ break;
+ if (!xfs_alloc_cur_active(cur))
+ break;
- if (!dir)
- error = xfs_btree_increment(scur, 0, &i);
+ if (increment)
+ error = xfs_btree_increment(cur, 0, &i);
else
- error = xfs_btree_decrement(scur, 0, &i);
+ error = xfs_btree_decrement(cur, 0, &i);
if (error)
- goto error0;
- } while (i);
-
-out_use_good:
- scur->bc_private.a.priv.abt.active = false;
- return 0;
+ return error;
+ if (i == 0)
+ cur->bc_private.a.priv.abt.active = false;
+ }
-out_use_search:
- gcur->bc_private.a.priv.abt.active = false;
return 0;
-
-error0:
- /* caller invalidates cursors */
- return error;
}
/*
struct xfs_alloc_arg *args)
{
struct xfs_alloc_cur acur = {};
- struct xfs_btree_cur *bno_cur;
- xfs_agblock_t gtbno; /* start bno of right side entry */
- xfs_agblock_t gtbnoa; /* aligned ... */
- xfs_extlen_t gtdiff; /* difference to right side entry */
- xfs_extlen_t gtlen; /* length of right side entry */
- xfs_extlen_t gtlena; /* aligned ... */
- xfs_agblock_t gtnew; /* useful start bno of right side */
- int error; /* error code */
- int i; /* result code, temporary */
- int j; /* result code, temporary */
- xfs_agblock_t ltbno; /* start bno of left side entry */
- xfs_agblock_t ltbnoa; /* aligned ... */
- xfs_extlen_t ltdiff; /* difference to left side entry */
- xfs_extlen_t ltlen; /* length of left side entry */
- xfs_extlen_t ltlena; /* aligned ... */
- xfs_agblock_t ltnew; /* useful start bno of left side */
- xfs_extlen_t rlen; /* length of returned extent */
+ struct xfs_btree_cur *fbcur = NULL;
+ int error; /* error code */
+ int i; /* result code, temporary */
+ int j; /* result code, temporary */
+ xfs_agblock_t bno;
+ xfs_extlen_t len;
+ bool fbinc = false;
#ifdef DEBUG
/*
* Randomly don't execute the first algorithm.
args->agbno = args->max_agbno;
restart:
- ltlen = 0;
- gtlena = 0;
- ltlena = 0;
+ len = 0;
/*
* Set up cursors and see if there are any free extents as big as
*/
error = xfs_alloc_cur_setup(args, &acur);
if (error == -ENOSPC) {
- error = xfs_alloc_ag_vextent_small(args, acur.cnt, <bno,
- <len, &i);
+ error = xfs_alloc_ag_vextent_small(args, acur.cnt, &bno,
+ &len, &i);
if (error)
goto out;
- if (i == 0 || ltlen == 0) {
+ if (i == 0 || len == 0) {
trace_xfs_alloc_near_noentry(args);
goto out;
}
* record smaller than maxlen, go to the start of this block,
* and skip all those smaller than minlen.
*/
- if (ltlen || args->alignment > 1) {
+ if (len || args->alignment > 1) {
acur.cnt->bc_ptrs[0] = 1;
do {
- error = xfs_alloc_get_rec(acur.cnt, <bno,
- <len, &i);
+ error = xfs_alloc_get_rec(acur.cnt, &bno, &len,
+ &i);
if (error)
goto out;
XFS_WANT_CORRUPTED_GOTO(args->mp, i == 1, out);
- if (ltlen >= args->minlen)
+ if (len >= args->minlen)
break;
error = xfs_btree_increment(acur.cnt, 0, &i);
if (error)
goto out;
} while (i);
- ASSERT(ltlen >= args->minlen);
+ ASSERT(len >= args->minlen);
if (!i)
break;
}
*/
do {
if (xfs_alloc_cur_active(acur.bnolt)) {
- error = xfs_alloc_get_rec(acur.bnolt, <bno, <len, &i);
+ error = xfs_alloc_cur_check(args, &acur, acur.bnolt, &i);
if (error)
goto out;
- XFS_WANT_CORRUPTED_GOTO(args->mp, i == 1, out);
- acur.busy |= xfs_alloc_compute_aligned(args, ltbno,
- ltlen, <bnoa, <lena, &acur.busy_gen);
- if (ltlena >= args->minlen && ltbnoa >= args->min_agbno)
+ if (i == 1) {
+ trace_xfs_alloc_cur_left(args);
+ fbcur = acur.bnogt;
+ fbinc = true;
break;
+ }
error = xfs_btree_decrement(acur.bnolt, 0, &i);
if (error)
goto out;
- if (!i || ltbnoa < args->min_agbno)
+ if (!i)
acur.bnolt->bc_private.a.priv.abt.active = false;
}
if (xfs_alloc_cur_active(acur.bnogt)) {
- error = xfs_alloc_get_rec(acur.bnogt, >bno, >len, &i);
+ error = xfs_alloc_cur_check(args, &acur, acur.bnogt, &i);
if (error)
goto out;
- XFS_WANT_CORRUPTED_GOTO(args->mp, i == 1, out);
- acur.busy |= xfs_alloc_compute_aligned(args, gtbno,
- gtlen, >bnoa, >lena, &acur.busy_gen);
- if (gtlena >= args->minlen && gtbnoa <= args->max_agbno)
+ if (i == 1) {
+ trace_xfs_alloc_cur_right(args);
+ fbcur = acur.bnolt;
+ fbinc = false;
break;
+ }
error = xfs_btree_increment(acur.bnogt, 0, &i);
if (error)
goto out;
- if (!i || gtbnoa > args->max_agbno)
+ if (!i)
acur.bnogt->bc_private.a.priv.abt.active = false;
}
} while (xfs_alloc_cur_active(acur.bnolt) ||
xfs_alloc_cur_active(acur.bnogt));
- /*
- * Got both cursors still active, need to find better entry.
- */
- if (xfs_alloc_cur_active(acur.bnolt) &&
- xfs_alloc_cur_active(acur.bnogt)) {
- if (ltlena >= args->minlen) {
- /*
- * Left side is good, look for a right side entry.
- */
- args->len = XFS_EXTLEN_MIN(ltlena, args->maxlen);
- xfs_alloc_fix_len(args);
- ltdiff = xfs_alloc_compute_diff(args->agbno, args->len,
- args->alignment, args->datatype, ltbnoa,
- ltlena, <new);
-
- error = xfs_alloc_find_best_extent(args,
- acur.bnolt, acur.bnogt,
- ltdiff, >bno, >len,
- >bnoa, >lena,
- 0 /* search right */);
- } else {
- ASSERT(gtlena >= args->minlen);
-
- /*
- * Right side is good, look for a left side entry.
- */
- args->len = XFS_EXTLEN_MIN(gtlena, args->maxlen);
- xfs_alloc_fix_len(args);
- gtdiff = xfs_alloc_compute_diff(args->agbno, args->len,
- args->alignment, args->datatype, gtbnoa,
- gtlena, >new);
-
- error = xfs_alloc_find_best_extent(args,
- acur.bnogt, acur.bnolt,
- gtdiff, <bno, <len,
- <bnoa, <lena,
- 1 /* search left */);
- }
-
+ /* search the opposite direction for a better entry */
+ if (fbcur) {
+ error = xfs_alloc_find_best_extent(args, &acur, fbcur, fbinc);
if (error)
goto out;
}
/*
* If we couldn't get anything, give up.
*/
- if (!xfs_alloc_cur_active(acur.bnolt) &&
- !xfs_alloc_cur_active(acur.bnogt)) {
+ if (!acur.len) {
if (acur.busy) {
trace_xfs_alloc_near_busy(args);
xfs_extent_busy_flush(args->mp, args->pag,
goto out;
}
- /*
- * At this point we have selected a freespace entry, either to the
- * left or to the right. If it's on the right, copy all the
- * useful variables to the "left" set so we only have one
- * copy of this code.
- */
- if (xfs_alloc_cur_active(acur.bnogt)) {
- bno_cur = acur.bnogt;
- ltbno = gtbno;
- ltbnoa = gtbnoa;
- ltlen = gtlen;
- ltlena = gtlena;
- j = 1;
- } else {
- bno_cur = acur.bnolt;
- j = 0;
- }
-
- /*
- * Fix up the length and compute the useful address.
- */
- args->len = XFS_EXTLEN_MIN(ltlena, args->maxlen);
- xfs_alloc_fix_len(args);
- rlen = args->len;
- (void)xfs_alloc_compute_diff(args->agbno, rlen, args->alignment,
- args->datatype, ltbnoa, ltlena, <new);
- ASSERT(ltnew >= ltbno);
- ASSERT(ltnew + rlen <= ltbnoa + ltlena);
- ASSERT(ltnew + rlen <= be32_to_cpu(XFS_BUF_TO_AGF(args->agbp)->agf_length));
- ASSERT(ltnew >= args->min_agbno && ltnew <= args->max_agbno);
- args->agbno = ltnew;
-
- error = xfs_alloc_fixup_trees(acur.cnt, bno_cur, ltbno, ltlen, ltnew,
- rlen, XFSA_FIXUP_BNO_OK);
- if (error)
- goto out;
+ args->agbno = acur.bno;
+ args->len = acur.len;
+ ASSERT(acur.bno >= acur.rec_bno);
+ ASSERT(acur.bno + acur.len <= acur.rec_bno + acur.rec_len);
+ ASSERT(acur.rec_bno + acur.rec_len <=
+ be32_to_cpu(XFS_BUF_TO_AGF(args->agbp)->agf_length));
- if (j)
- trace_xfs_alloc_near_greater(args);
- else
- trace_xfs_alloc_near_lesser(args);
+ error = xfs_alloc_fixup_trees(acur.cnt, acur.bnolt, acur.rec_bno,
+ acur.rec_len, acur.bno, acur.len, 0);
out:
xfs_alloc_cur_close(&acur, error);
projects / linux.git / commitdiff