diff options
Diffstat (limited to 'fs/ocfs2/suballoc.c')
| -rw-r--r-- | fs/ocfs2/suballoc.c | 155 |
1 files changed, 129 insertions, 26 deletions
diff --git a/fs/ocfs2/suballoc.c b/fs/ocfs2/suballoc.c index 166c8918c825..6ac4dcd54588 100644 --- a/fs/ocfs2/suballoc.c +++ b/fs/ocfs2/suballoc.c @@ -50,6 +50,10 @@ struct ocfs2_suballoc_result { u64 sr_blkno; /* The first allocated block */ unsigned int sr_bit_offset; /* The bit in the bg */ unsigned int sr_bits; /* How many bits we claimed */ + unsigned int sr_max_contig_bits; /* The length for contiguous + * free bits, only available + * for cluster group + */ }; static u64 ocfs2_group_from_res(struct ocfs2_suballoc_result *res) @@ -694,10 +698,12 @@ static int ocfs2_block_group_alloc(struct ocfs2_super *osb, bg_bh = ocfs2_block_group_alloc_contig(osb, handle, alloc_inode, ac, cl); - if (PTR_ERR(bg_bh) == -ENOSPC) + if (PTR_ERR(bg_bh) == -ENOSPC) { + ac->ac_which = OCFS2_AC_USE_MAIN_DISCONTIG; bg_bh = ocfs2_block_group_alloc_discontig(handle, alloc_inode, ac, cl); + } if (IS_ERR(bg_bh)) { status = PTR_ERR(bg_bh); bg_bh = NULL; @@ -1272,6 +1278,26 @@ static int ocfs2_test_bg_bit_allocatable(struct buffer_head *bg_bh, return ret; } +u16 ocfs2_find_max_contig_free_bits(void *bitmap, + u16 total_bits, u16 start) +{ + u16 offset, free_bits; + u16 contig_bits = 0; + + while (start < total_bits) { + offset = ocfs2_find_next_zero_bit(bitmap, total_bits, start); + if (offset == total_bits) + break; + + start = ocfs2_find_next_bit(bitmap, total_bits, offset); + free_bits = start - offset; + if (contig_bits < free_bits) + contig_bits = free_bits; + } + + return contig_bits; +} + static int ocfs2_block_group_find_clear_bits(struct ocfs2_super *osb, struct buffer_head *bg_bh, unsigned int bits_wanted, @@ -1280,6 +1306,7 @@ static int ocfs2_block_group_find_clear_bits(struct ocfs2_super *osb, { void *bitmap; u16 best_offset, best_size; + u16 prev_best_size = 0; int offset, start, found, status = 0; struct ocfs2_group_desc *bg = (struct ocfs2_group_desc *) bg_bh->b_data; @@ -1290,10 +1317,8 @@ static int ocfs2_block_group_find_clear_bits(struct ocfs2_super *osb, found = start = best_offset = best_size = 0; bitmap = bg->bg_bitmap; - while((offset = ocfs2_find_next_zero_bit(bitmap, total_bits, start)) != -1) { - if (offset == total_bits) - break; - + while ((offset = ocfs2_find_next_zero_bit(bitmap, total_bits, start)) < + total_bits) { if (!ocfs2_test_bg_bit_allocatable(bg_bh, offset)) { /* We found a zero, but we can't use it as it * hasn't been put to disk yet! */ @@ -1308,6 +1333,7 @@ static int ocfs2_block_group_find_clear_bits(struct ocfs2_super *osb, /* got a zero after some ones */ found = 1; start = offset + 1; + prev_best_size = best_size; } if (found > best_size) { best_size = found; @@ -1320,6 +1346,8 @@ static int ocfs2_block_group_find_clear_bits(struct ocfs2_super *osb, } } + /* best_size will be allocated, we save prev_best_size */ + res->sr_max_contig_bits = prev_best_size; if (best_size) { res->sr_bit_offset = best_offset; res->sr_bits = best_size; @@ -1337,11 +1365,16 @@ int ocfs2_block_group_set_bits(handle_t *handle, struct ocfs2_group_desc *bg, struct buffer_head *group_bh, unsigned int bit_off, - unsigned int num_bits) + unsigned int num_bits, + unsigned int max_contig_bits, + int fastpath) { int status; void *bitmap = bg->bg_bitmap; int journal_type = OCFS2_JOURNAL_ACCESS_WRITE; + unsigned int start = bit_off + num_bits; + u16 contig_bits; + struct ocfs2_super *osb = OCFS2_SB(alloc_inode->i_sb); /* All callers get the descriptor via * ocfs2_read_group_descriptor(). Any corruption is a code bug. */ @@ -1373,6 +1406,29 @@ int ocfs2_block_group_set_bits(handle_t *handle, while(num_bits--) ocfs2_set_bit(bit_off++, bitmap); + /* + * this is optimize path, caller set old contig value + * in max_contig_bits to bypass finding action. + */ + if (fastpath) { + bg->bg_contig_free_bits = cpu_to_le16(max_contig_bits); + } else if (ocfs2_is_cluster_bitmap(alloc_inode)) { + /* + * Usually, the block group bitmap allocates only 1 bit + * at a time, while the cluster group allocates n bits + * each time. Therefore, we only save the contig bits for + * the cluster group. + */ + contig_bits = ocfs2_find_max_contig_free_bits(bitmap, + le16_to_cpu(bg->bg_bits), start); + if (contig_bits > max_contig_bits) + max_contig_bits = contig_bits; + bg->bg_contig_free_bits = cpu_to_le16(max_contig_bits); + ocfs2_local_alloc_seen_free_bits(osb, max_contig_bits); + } else { + bg->bg_contig_free_bits = 0; + } + ocfs2_journal_dirty(handle, group_bh); bail: @@ -1486,7 +1542,12 @@ static int ocfs2_cluster_group_search(struct inode *inode, BUG_ON(!ocfs2_is_cluster_bitmap(inode)); - if (gd->bg_free_bits_count) { + if (le16_to_cpu(gd->bg_contig_free_bits) && + le16_to_cpu(gd->bg_contig_free_bits) < bits_wanted) + return -ENOSPC; + + /* ->bg_contig_free_bits may un-initialized, so compare again */ + if (le16_to_cpu(gd->bg_free_bits_count) >= bits_wanted) { max_bits = le16_to_cpu(gd->bg_bits); /* Tail groups in cluster bitmaps which aren't cpg @@ -1530,13 +1591,6 @@ static int ocfs2_cluster_group_search(struct inode *inode, * of bits. */ if (min_bits <= res->sr_bits) search = 0; /* success */ - else if (res->sr_bits) { - /* - * Don't show bits which we'll be returning - * for allocation to the local alloc bitmap. - */ - ocfs2_local_alloc_seen_free_bits(osb, res->sr_bits); - } } return search; @@ -1555,7 +1609,7 @@ static int ocfs2_block_group_search(struct inode *inode, BUG_ON(min_bits != 1); BUG_ON(ocfs2_is_cluster_bitmap(inode)); - if (bg->bg_free_bits_count) { + if (le16_to_cpu(bg->bg_free_bits_count) >= bits_wanted) { ret = ocfs2_block_group_find_clear_bits(OCFS2_SB(inode->i_sb), group_bh, bits_wanted, le16_to_cpu(bg->bg_bits), @@ -1715,7 +1769,8 @@ static int ocfs2_search_one_group(struct ocfs2_alloc_context *ac, } ret = ocfs2_block_group_set_bits(handle, alloc_inode, gd, group_bh, - res->sr_bit_offset, res->sr_bits); + res->sr_bit_offset, res->sr_bits, + res->sr_max_contig_bits, 0); if (ret < 0) { ocfs2_rollback_alloc_dinode_counts(alloc_inode, ac->ac_bh, res->sr_bits, @@ -1741,6 +1796,7 @@ static int ocfs2_search_chain(struct ocfs2_alloc_context *ac, { int status; u16 chain; + u32 contig_bits; u64 next_group; struct inode *alloc_inode = ac->ac_inode; struct buffer_head *group_bh = NULL; @@ -1766,10 +1822,21 @@ static int ocfs2_search_chain(struct ocfs2_alloc_context *ac, status = -ENOSPC; /* for now, the chain search is a bit simplistic. We just use * the 1st group with any empty bits. */ - while ((status = ac->ac_group_search(alloc_inode, group_bh, - bits_wanted, min_bits, - ac->ac_max_block, - res)) == -ENOSPC) { + while (1) { + if (ac->ac_which == OCFS2_AC_USE_MAIN_DISCONTIG) { + contig_bits = le16_to_cpu(bg->bg_contig_free_bits); + if (!contig_bits) + contig_bits = ocfs2_find_max_contig_free_bits(bg->bg_bitmap, + le16_to_cpu(bg->bg_bits), 0); + if (bits_wanted > contig_bits && contig_bits >= min_bits) + bits_wanted = contig_bits; + } + + status = ac->ac_group_search(alloc_inode, group_bh, + bits_wanted, min_bits, + ac->ac_max_block, res); + if (status != -ENOSPC) + break; if (!bg->bg_next_group) break; @@ -1849,7 +1916,9 @@ static int ocfs2_search_chain(struct ocfs2_alloc_context *ac, bg, group_bh, res->sr_bit_offset, - res->sr_bits); + res->sr_bits, + res->sr_max_contig_bits, + 0); if (status < 0) { ocfs2_rollback_alloc_dinode_counts(alloc_inode, ac->ac_bh, res->sr_bits, chain); @@ -1927,6 +1996,7 @@ static int ocfs2_claim_suballoc_bits(struct ocfs2_alloc_context *ac, victim = ocfs2_find_victim_chain(cl); ac->ac_chain = victim; +search: status = ocfs2_search_chain(ac, handle, bits_wanted, min_bits, res, &bits_left); if (!status) { @@ -1951,7 +2021,7 @@ static int ocfs2_claim_suballoc_bits(struct ocfs2_alloc_context *ac, for (i = 0; i < le16_to_cpu(cl->cl_next_free_rec); i ++) { if (i == victim) continue; - if (!cl->cl_recs[i].c_free) + if (le32_to_cpu(cl->cl_recs[i].c_free) < bits_wanted) continue; ac->ac_chain = i; @@ -1967,6 +2037,16 @@ static int ocfs2_claim_suballoc_bits(struct ocfs2_alloc_context *ac, } } + /* Chains can't supply the bits_wanted contiguous space. + * We should switch to using every single bit when allocating + * from the global bitmap. */ + if (i == le16_to_cpu(cl->cl_next_free_rec) && + status == -ENOSPC && ac->ac_which == OCFS2_AC_USE_MAIN) { + ac->ac_which = OCFS2_AC_USE_MAIN_DISCONTIG; + ac->ac_chain = victim; + goto search; + } + set_hint: if (status != -ENOSPC) { /* If the next search of this group is not likely to @@ -2163,7 +2243,9 @@ int ocfs2_claim_new_inode_at_loc(handle_t *handle, bg, bg_bh, res->sr_bit_offset, - res->sr_bits); + res->sr_bits, + res->sr_max_contig_bits, + 0); if (ret < 0) { ocfs2_rollback_alloc_dinode_counts(ac->ac_inode, ac->ac_bh, res->sr_bits, chain); @@ -2308,7 +2390,8 @@ int __ocfs2_claim_clusters(handle_t *handle, BUG_ON(ac->ac_bits_given >= ac->ac_bits_wanted); BUG_ON(ac->ac_which != OCFS2_AC_USE_LOCAL - && ac->ac_which != OCFS2_AC_USE_MAIN); + && ac->ac_which != OCFS2_AC_USE_MAIN + && ac->ac_which != OCFS2_AC_USE_MAIN_DISCONTIG); if (ac->ac_which == OCFS2_AC_USE_LOCAL) { WARN_ON(min_clusters > 1); @@ -2382,11 +2465,13 @@ static int ocfs2_block_group_clear_bits(handle_t *handle, struct buffer_head *group_bh, unsigned int bit_off, unsigned int num_bits, + unsigned int max_contig_bits, void (*undo_fn)(unsigned int bit, unsigned long *bmap)) { int status; unsigned int tmp; + u16 contig_bits; struct ocfs2_group_desc *undo_bg = NULL; struct journal_head *jh; @@ -2433,6 +2518,20 @@ static int ocfs2_block_group_clear_bits(handle_t *handle, num_bits); } + /* + * TODO: even 'num_bits == 1' (the worst case, release 1 cluster), + * we still need to rescan whole bitmap. + */ + if (ocfs2_is_cluster_bitmap(alloc_inode)) { + contig_bits = ocfs2_find_max_contig_free_bits(bg->bg_bitmap, + le16_to_cpu(bg->bg_bits), 0); + if (contig_bits > max_contig_bits) + max_contig_bits = contig_bits; + bg->bg_contig_free_bits = cpu_to_le16(max_contig_bits); + } else { + bg->bg_contig_free_bits = 0; + } + if (undo_fn) spin_unlock(&jh->b_state_lock); @@ -2459,6 +2558,7 @@ static int _ocfs2_free_suballoc_bits(handle_t *handle, struct ocfs2_chain_list *cl = &fe->id2.i_chain; struct buffer_head *group_bh = NULL; struct ocfs2_group_desc *group; + __le16 old_bg_contig_free_bits = 0; /* The alloc_bh comes from ocfs2_free_dinode() or * ocfs2_free_clusters(). The callers have all locked the @@ -2483,9 +2583,11 @@ static int _ocfs2_free_suballoc_bits(handle_t *handle, BUG_ON((count + start_bit) > le16_to_cpu(group->bg_bits)); + if (ocfs2_is_cluster_bitmap(alloc_inode)) + old_bg_contig_free_bits = group->bg_contig_free_bits; status = ocfs2_block_group_clear_bits(handle, alloc_inode, group, group_bh, - start_bit, count, undo_fn); + start_bit, count, 0, undo_fn); if (status < 0) { mlog_errno(status); goto bail; @@ -2496,7 +2598,8 @@ static int _ocfs2_free_suballoc_bits(handle_t *handle, if (status < 0) { mlog_errno(status); ocfs2_block_group_set_bits(handle, alloc_inode, group, group_bh, - start_bit, count); + start_bit, count, + le16_to_cpu(old_bg_contig_free_bits), 1); goto bail; } |