diff options
Diffstat (limited to 'fs/ext4/mballoc.c')
| -rw-r--r-- | fs/ext4/mballoc.c | 895 |
1 files changed, 502 insertions, 393 deletions
diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c index 1e98c5be4e0a..5898d92ba19f 100644 --- a/fs/ext4/mballoc.c +++ b/fs/ext4/mballoc.c @@ -132,25 +132,30 @@ * If "mb_optimize_scan" mount option is set, we maintain in memory group info * structures in two data structures: * - * 1) Array of largest free order lists (sbi->s_mb_largest_free_orders) + * 1) Array of largest free order xarrays (sbi->s_mb_largest_free_orders) * - * Locking: sbi->s_mb_largest_free_orders_locks(array of rw locks) + * Locking: Writers use xa_lock, readers use rcu_read_lock. * - * This is an array of lists where the index in the array represents the + * This is an array of xarrays where the index in the array represents the * largest free order in the buddy bitmap of the participating group infos of - * that list. So, there are exactly MB_NUM_ORDERS(sb) (which means total - * number of buddy bitmap orders possible) number of lists. Group-infos are - * placed in appropriate lists. + * that xarray. So, there are exactly MB_NUM_ORDERS(sb) (which means total + * number of buddy bitmap orders possible) number of xarrays. Group-infos are + * placed in appropriate xarrays. * - * 2) Average fragment size lists (sbi->s_mb_avg_fragment_size) + * 2) Average fragment size xarrays (sbi->s_mb_avg_fragment_size) * - * Locking: sbi->s_mb_avg_fragment_size_locks(array of rw locks) + * Locking: Writers use xa_lock, readers use rcu_read_lock. * - * This is an array of lists where in the i-th list there are groups with + * This is an array of xarrays where in the i-th xarray there are groups with * average fragment size >= 2^i and < 2^(i+1). The average fragment size * is computed as ext4_group_info->bb_free / ext4_group_info->bb_fragments. - * Note that we don't bother with a special list for completely empty groups - * so we only have MB_NUM_ORDERS(sb) lists. + * Note that we don't bother with a special xarray for completely empty + * groups so we only have MB_NUM_ORDERS(sb) xarrays. Group-infos are placed + * in appropriate xarrays. + * + * In xarray, the index is the block group number, the value is the block group + * information, and a non-empty value indicates the block group is present in + * the current xarray. * * When "mb_optimize_scan" mount option is set, mballoc consults the above data * structures to decide the order in which groups are to be traversed for @@ -420,8 +425,8 @@ static void ext4_mb_generate_from_pa(struct super_block *sb, void *bitmap, ext4_group_t group); static void ext4_mb_new_preallocation(struct ext4_allocation_context *ac); -static bool ext4_mb_good_group(struct ext4_allocation_context *ac, - ext4_group_t group, enum criteria cr); +static int ext4_mb_scan_group(struct ext4_allocation_context *ac, + ext4_group_t group); static int ext4_try_to_trim_range(struct super_block *sb, struct ext4_buddy *e4b, ext4_grpblk_t start, @@ -841,132 +846,161 @@ static void mb_update_avg_fragment_size(struct super_block *sb, struct ext4_group_info *grp) { struct ext4_sb_info *sbi = EXT4_SB(sb); - int new_order; + int new, old; - if (!test_opt2(sb, MB_OPTIMIZE_SCAN) || grp->bb_fragments == 0) + if (!test_opt2(sb, MB_OPTIMIZE_SCAN)) return; - new_order = mb_avg_fragment_size_order(sb, - grp->bb_free / grp->bb_fragments); - if (new_order == grp->bb_avg_fragment_size_order) + old = grp->bb_avg_fragment_size_order; + new = grp->bb_fragments == 0 ? -1 : + mb_avg_fragment_size_order(sb, grp->bb_free / grp->bb_fragments); + if (new == old) return; - if (grp->bb_avg_fragment_size_order != -1) { - write_lock(&sbi->s_mb_avg_fragment_size_locks[ - grp->bb_avg_fragment_size_order]); - list_del(&grp->bb_avg_fragment_size_node); - write_unlock(&sbi->s_mb_avg_fragment_size_locks[ - grp->bb_avg_fragment_size_order]); + if (old >= 0) + xa_erase(&sbi->s_mb_avg_fragment_size[old], grp->bb_group); + + grp->bb_avg_fragment_size_order = new; + if (new >= 0) { + /* + * Cannot use __GFP_NOFAIL because we hold the group lock. + * Although allocation for insertion may fails, it's not fatal + * as we have linear traversal to fall back on. + */ + int err = xa_insert(&sbi->s_mb_avg_fragment_size[new], + grp->bb_group, grp, GFP_ATOMIC); + if (err) + mb_debug(sb, "insert group: %u to s_mb_avg_fragment_size[%d] failed, err %d", + grp->bb_group, new, err); + } +} + +static int ext4_mb_scan_groups_xa_range(struct ext4_allocation_context *ac, + struct xarray *xa, + ext4_group_t start, ext4_group_t end) +{ + struct super_block *sb = ac->ac_sb; + struct ext4_sb_info *sbi = EXT4_SB(sb); + enum criteria cr = ac->ac_criteria; + ext4_group_t ngroups = ext4_get_groups_count(sb); + unsigned long group = start; + struct ext4_group_info *grp; + + if (WARN_ON_ONCE(end > ngroups || start >= end)) + return 0; + + xa_for_each_range(xa, group, grp, start, end - 1) { + int err; + + if (sbi->s_mb_stats) + atomic64_inc(&sbi->s_bal_cX_groups_considered[cr]); + + err = ext4_mb_scan_group(ac, grp->bb_group); + if (err || ac->ac_status != AC_STATUS_CONTINUE) + return err; + + cond_resched(); } - grp->bb_avg_fragment_size_order = new_order; - write_lock(&sbi->s_mb_avg_fragment_size_locks[ - grp->bb_avg_fragment_size_order]); - list_add_tail(&grp->bb_avg_fragment_size_node, - &sbi->s_mb_avg_fragment_size[grp->bb_avg_fragment_size_order]); - write_unlock(&sbi->s_mb_avg_fragment_size_locks[ - grp->bb_avg_fragment_size_order]); + + return 0; +} + +/* + * Find a suitable group of given order from the largest free orders xarray. + */ +static inline int +ext4_mb_scan_groups_largest_free_order_range(struct ext4_allocation_context *ac, + int order, ext4_group_t start, + ext4_group_t end) +{ + struct xarray *xa = &EXT4_SB(ac->ac_sb)->s_mb_largest_free_orders[order]; + + if (xa_empty(xa)) + return 0; + + return ext4_mb_scan_groups_xa_range(ac, xa, start, end); } /* * Choose next group by traversing largest_free_order lists. Updates *new_cr if * cr level needs an update. */ -static void ext4_mb_choose_next_group_p2_aligned(struct ext4_allocation_context *ac, - enum criteria *new_cr, ext4_group_t *group) +static int ext4_mb_scan_groups_p2_aligned(struct ext4_allocation_context *ac, + ext4_group_t group) { struct ext4_sb_info *sbi = EXT4_SB(ac->ac_sb); - struct ext4_group_info *iter; int i; + int ret = 0; + ext4_group_t start, end; - if (ac->ac_status == AC_STATUS_FOUND) - return; - - if (unlikely(sbi->s_mb_stats && ac->ac_flags & EXT4_MB_CR_POWER2_ALIGNED_OPTIMIZED)) - atomic_inc(&sbi->s_bal_p2_aligned_bad_suggestions); - + start = group; + end = ext4_get_groups_count(ac->ac_sb); +wrap_around: for (i = ac->ac_2order; i < MB_NUM_ORDERS(ac->ac_sb); i++) { - if (list_empty(&sbi->s_mb_largest_free_orders[i])) - continue; - read_lock(&sbi->s_mb_largest_free_orders_locks[i]); - if (list_empty(&sbi->s_mb_largest_free_orders[i])) { - read_unlock(&sbi->s_mb_largest_free_orders_locks[i]); - continue; - } - list_for_each_entry(iter, &sbi->s_mb_largest_free_orders[i], - bb_largest_free_order_node) { - if (sbi->s_mb_stats) - atomic64_inc(&sbi->s_bal_cX_groups_considered[CR_POWER2_ALIGNED]); - if (likely(ext4_mb_good_group(ac, iter->bb_group, CR_POWER2_ALIGNED))) { - *group = iter->bb_group; - ac->ac_flags |= EXT4_MB_CR_POWER2_ALIGNED_OPTIMIZED; - read_unlock(&sbi->s_mb_largest_free_orders_locks[i]); - return; - } - } - read_unlock(&sbi->s_mb_largest_free_orders_locks[i]); + ret = ext4_mb_scan_groups_largest_free_order_range(ac, i, + start, end); + if (ret || ac->ac_status != AC_STATUS_CONTINUE) + return ret; + } + if (start) { + end = start; + start = 0; + goto wrap_around; } + if (sbi->s_mb_stats) + atomic64_inc(&sbi->s_bal_cX_failed[ac->ac_criteria]); + /* Increment cr and search again if no group is found */ - *new_cr = CR_GOAL_LEN_FAST; + ac->ac_criteria = CR_GOAL_LEN_FAST; + return ret; } /* - * Find a suitable group of given order from the average fragments list. + * Find a suitable group of given order from the average fragments xarray. */ -static struct ext4_group_info * -ext4_mb_find_good_group_avg_frag_lists(struct ext4_allocation_context *ac, int order) +static int +ext4_mb_scan_groups_avg_frag_order_range(struct ext4_allocation_context *ac, + int order, ext4_group_t start, + ext4_group_t end) { - struct ext4_sb_info *sbi = EXT4_SB(ac->ac_sb); - struct list_head *frag_list = &sbi->s_mb_avg_fragment_size[order]; - rwlock_t *frag_list_lock = &sbi->s_mb_avg_fragment_size_locks[order]; - struct ext4_group_info *grp = NULL, *iter; - enum criteria cr = ac->ac_criteria; + struct xarray *xa = &EXT4_SB(ac->ac_sb)->s_mb_avg_fragment_size[order]; - if (list_empty(frag_list)) - return NULL; - read_lock(frag_list_lock); - if (list_empty(frag_list)) { - read_unlock(frag_list_lock); - return NULL; - } - list_for_each_entry(iter, frag_list, bb_avg_fragment_size_node) { - if (sbi->s_mb_stats) - atomic64_inc(&sbi->s_bal_cX_groups_considered[cr]); - if (likely(ext4_mb_good_group(ac, iter->bb_group, cr))) { - grp = iter; - break; - } - } - read_unlock(frag_list_lock); - return grp; + if (xa_empty(xa)) + return 0; + + return ext4_mb_scan_groups_xa_range(ac, xa, start, end); } /* * Choose next group by traversing average fragment size list of suitable * order. Updates *new_cr if cr level needs an update. */ -static void ext4_mb_choose_next_group_goal_fast(struct ext4_allocation_context *ac, - enum criteria *new_cr, ext4_group_t *group) +static int ext4_mb_scan_groups_goal_fast(struct ext4_allocation_context *ac, + ext4_group_t group) { struct ext4_sb_info *sbi = EXT4_SB(ac->ac_sb); - struct ext4_group_info *grp = NULL; - int i; - - if (unlikely(ac->ac_flags & EXT4_MB_CR_GOAL_LEN_FAST_OPTIMIZED)) { - if (sbi->s_mb_stats) - atomic_inc(&sbi->s_bal_goal_fast_bad_suggestions); + int i, ret = 0; + ext4_group_t start, end; + + start = group; + end = ext4_get_groups_count(ac->ac_sb); +wrap_around: + i = mb_avg_fragment_size_order(ac->ac_sb, ac->ac_g_ex.fe_len); + for (; i < MB_NUM_ORDERS(ac->ac_sb); i++) { + ret = ext4_mb_scan_groups_avg_frag_order_range(ac, i, + start, end); + if (ret || ac->ac_status != AC_STATUS_CONTINUE) + return ret; } - - for (i = mb_avg_fragment_size_order(ac->ac_sb, ac->ac_g_ex.fe_len); - i < MB_NUM_ORDERS(ac->ac_sb); i++) { - grp = ext4_mb_find_good_group_avg_frag_lists(ac, i); - if (grp) { - *group = grp->bb_group; - ac->ac_flags |= EXT4_MB_CR_GOAL_LEN_FAST_OPTIMIZED; - return; - } + if (start) { + end = start; + start = 0; + goto wrap_around; } + if (sbi->s_mb_stats) + atomic64_inc(&sbi->s_bal_cX_failed[ac->ac_criteria]); /* * CR_BEST_AVAIL_LEN works based on the concept that we have * a larger normalized goal len request which can be trimmed to @@ -976,9 +1010,11 @@ static void ext4_mb_choose_next_group_goal_fast(struct ext4_allocation_context * * See function ext4_mb_normalize_request() (EXT4_MB_HINT_DATA). */ if (ac->ac_flags & EXT4_MB_HINT_DATA) - *new_cr = CR_BEST_AVAIL_LEN; + ac->ac_criteria = CR_BEST_AVAIL_LEN; else - *new_cr = CR_GOAL_LEN_SLOW; + ac->ac_criteria = CR_GOAL_LEN_SLOW; + + return ret; } /* @@ -990,18 +1026,14 @@ static void ext4_mb_choose_next_group_goal_fast(struct ext4_allocation_context * * preallocations. However, we make sure that we don't trim the request too * much and fall to CR_GOAL_LEN_SLOW in that case. */ -static void ext4_mb_choose_next_group_best_avail(struct ext4_allocation_context *ac, - enum criteria *new_cr, ext4_group_t *group) +static int ext4_mb_scan_groups_best_avail(struct ext4_allocation_context *ac, + ext4_group_t group) { + int ret = 0; struct ext4_sb_info *sbi = EXT4_SB(ac->ac_sb); - struct ext4_group_info *grp = NULL; int i, order, min_order; unsigned long num_stripe_clusters = 0; - - if (unlikely(ac->ac_flags & EXT4_MB_CR_BEST_AVAIL_LEN_OPTIMIZED)) { - if (sbi->s_mb_stats) - atomic_inc(&sbi->s_bal_best_avail_bad_suggestions); - } + ext4_group_t start, end; /* * mb_avg_fragment_size_order() returns order in a way that makes @@ -1033,6 +1065,9 @@ static void ext4_mb_choose_next_group_best_avail(struct ext4_allocation_context if (1 << min_order < ac->ac_o_ex.fe_len) min_order = fls(ac->ac_o_ex.fe_len); + start = group; + end = ext4_get_groups_count(ac->ac_sb); +wrap_around: for (i = order; i >= min_order; i--) { int frag_order; /* @@ -1055,17 +1090,24 @@ static void ext4_mb_choose_next_group_best_avail(struct ext4_allocation_context frag_order = mb_avg_fragment_size_order(ac->ac_sb, ac->ac_g_ex.fe_len); - grp = ext4_mb_find_good_group_avg_frag_lists(ac, frag_order); - if (grp) { - *group = grp->bb_group; - ac->ac_flags |= EXT4_MB_CR_BEST_AVAIL_LEN_OPTIMIZED; - return; - } + ret = ext4_mb_scan_groups_avg_frag_order_range(ac, frag_order, + start, end); + if (ret || ac->ac_status != AC_STATUS_CONTINUE) + return ret; + } + if (start) { + end = start; + start = 0; + goto wrap_around; } /* Reset goal length to original goal length before falling into CR_GOAL_LEN_SLOW */ ac->ac_g_ex.fe_len = ac->ac_orig_goal_len; - *new_cr = CR_GOAL_LEN_SLOW; + if (sbi->s_mb_stats) + atomic64_inc(&sbi->s_bal_cX_failed[ac->ac_criteria]); + ac->ac_criteria = CR_GOAL_LEN_SLOW; + + return ret; } static inline int should_optimize_scan(struct ext4_allocation_context *ac) @@ -1080,59 +1122,82 @@ static inline int should_optimize_scan(struct ext4_allocation_context *ac) } /* - * Return next linear group for allocation. + * next linear group for allocation. */ -static ext4_group_t -next_linear_group(ext4_group_t group, ext4_group_t ngroups) +static void next_linear_group(ext4_group_t *group, ext4_group_t ngroups) { /* * Artificially restricted ngroups for non-extent * files makes group > ngroups possible on first loop. */ - return group + 1 >= ngroups ? 0 : group + 1; + *group = *group + 1 >= ngroups ? 0 : *group + 1; } -/* - * ext4_mb_choose_next_group: choose next group for allocation. - * - * @ac Allocation Context - * @new_cr This is an output parameter. If the there is no good group - * available at current CR level, this field is updated to indicate - * the new cr level that should be used. - * @group This is an input / output parameter. As an input it indicates the - * next group that the allocator intends to use for allocation. As - * output, this field indicates the next group that should be used as - * determined by the optimization functions. - * @ngroups Total number of groups - */ -static void ext4_mb_choose_next_group(struct ext4_allocation_context *ac, - enum criteria *new_cr, ext4_group_t *group, ext4_group_t ngroups) +static int ext4_mb_scan_groups_linear(struct ext4_allocation_context *ac, + ext4_group_t ngroups, ext4_group_t *start, ext4_group_t count) { - *new_cr = ac->ac_criteria; + int ret, i; + enum criteria cr = ac->ac_criteria; + struct super_block *sb = ac->ac_sb; + struct ext4_sb_info *sbi = EXT4_SB(sb); + ext4_group_t group = *start; - if (!should_optimize_scan(ac)) { - *group = next_linear_group(*group, ngroups); - return; + for (i = 0; i < count; i++, next_linear_group(&group, ngroups)) { + ret = ext4_mb_scan_group(ac, group); + if (ret || ac->ac_status != AC_STATUS_CONTINUE) + return ret; + cond_resched(); } + *start = group; + if (count == ngroups) + ac->ac_criteria++; + + /* Processed all groups and haven't found blocks */ + if (sbi->s_mb_stats && i == ngroups) + atomic64_inc(&sbi->s_bal_cX_failed[cr]); + + return 0; +} + +static int ext4_mb_scan_groups(struct ext4_allocation_context *ac) +{ + int ret = 0; + ext4_group_t start; + struct ext4_sb_info *sbi = EXT4_SB(ac->ac_sb); + ext4_group_t ngroups = ext4_get_groups_count(ac->ac_sb); + + /* non-extent files are limited to low blocks/groups */ + if (!(ext4_test_inode_flag(ac->ac_inode, EXT4_INODE_EXTENTS))) + ngroups = sbi->s_blockfile_groups; + + /* searching for the right group start from the goal value specified */ + start = ac->ac_g_ex.fe_group; + ac->ac_prefetch_grp = start; + ac->ac_prefetch_nr = 0; + + if (!should_optimize_scan(ac)) + return ext4_mb_scan_groups_linear(ac, ngroups, &start, ngroups); + /* * Optimized scanning can return non adjacent groups which can cause * seek overhead for rotational disks. So try few linear groups before * trying optimized scan. */ - if (ac->ac_groups_linear_remaining) { - *group = next_linear_group(*group, ngroups); - ac->ac_groups_linear_remaining--; - return; - } + if (sbi->s_mb_max_linear_groups) + ret = ext4_mb_scan_groups_linear(ac, ngroups, &start, + sbi->s_mb_max_linear_groups); + if (ret || ac->ac_status != AC_STATUS_CONTINUE) + return ret; - if (*new_cr == CR_POWER2_ALIGNED) { - ext4_mb_choose_next_group_p2_aligned(ac, new_cr, group); - } else if (*new_cr == CR_GOAL_LEN_FAST) { - ext4_mb_choose_next_group_goal_fast(ac, new_cr, group); - } else if (*new_cr == CR_BEST_AVAIL_LEN) { - ext4_mb_choose_next_group_best_avail(ac, new_cr, group); - } else { + switch (ac->ac_criteria) { + case CR_POWER2_ALIGNED: + return ext4_mb_scan_groups_p2_aligned(ac, start); + case CR_GOAL_LEN_FAST: + return ext4_mb_scan_groups_goal_fast(ac, start); + case CR_BEST_AVAIL_LEN: + return ext4_mb_scan_groups_best_avail(ac, start); + default: /* * TODO: For CR_GOAL_LEN_SLOW, we can arrange groups in an * rb tree sorted by bb_free. But until that happens, we should @@ -1140,6 +1205,8 @@ static void ext4_mb_choose_next_group(struct ext4_allocation_context *ac, */ WARN_ON(1); } + + return 0; } /* @@ -1150,33 +1217,35 @@ static void mb_set_largest_free_order(struct super_block *sb, struct ext4_group_info *grp) { struct ext4_sb_info *sbi = EXT4_SB(sb); - int i; + int new, old = grp->bb_largest_free_order; - for (i = MB_NUM_ORDERS(sb) - 1; i >= 0; i--) - if (grp->bb_counters[i] > 0) + for (new = MB_NUM_ORDERS(sb) - 1; new >= 0; new--) + if (grp->bb_counters[new] > 0) break; + /* No need to move between order lists? */ - if (!test_opt2(sb, MB_OPTIMIZE_SCAN) || - i == grp->bb_largest_free_order) { - grp->bb_largest_free_order = i; + if (new == old) return; - } - if (grp->bb_largest_free_order >= 0) { - write_lock(&sbi->s_mb_largest_free_orders_locks[ - grp->bb_largest_free_order]); - list_del_init(&grp->bb_largest_free_order_node); - write_unlock(&sbi->s_mb_largest_free_orders_locks[ - grp->bb_largest_free_order]); + if (old >= 0) { + struct xarray *xa = &sbi->s_mb_largest_free_orders[old]; + + if (!xa_empty(xa) && xa_load(xa, grp->bb_group)) + xa_erase(xa, grp->bb_group); } - grp->bb_largest_free_order = i; - if (grp->bb_largest_free_order >= 0 && grp->bb_free) { - write_lock(&sbi->s_mb_largest_free_orders_locks[ - grp->bb_largest_free_order]); - list_add_tail(&grp->bb_largest_free_order_node, - &sbi->s_mb_largest_free_orders[grp->bb_largest_free_order]); - write_unlock(&sbi->s_mb_largest_free_orders_locks[ - grp->bb_largest_free_order]); + + grp->bb_largest_free_order = new; + if (test_opt2(sb, MB_OPTIMIZE_SCAN) && new >= 0 && grp->bb_free) { + /* + * Cannot use __GFP_NOFAIL because we hold the group lock. + * Although allocation for insertion may fails, it's not fatal + * as we have linear traversal to fall back on. + */ + int err = xa_insert(&sbi->s_mb_largest_free_orders[new], + grp->bb_group, grp, GFP_ATOMIC); + if (err) + mb_debug(sb, "insert group: %u to s_mb_largest_free_orders[%d] failed, err %d", + grp->bb_group, new, err); } } @@ -2167,11 +2236,11 @@ static void ext4_mb_use_best_found(struct ext4_allocation_context *ac, folio_get(ac->ac_buddy_folio); /* store last allocated for subsequent stream allocation */ if (ac->ac_flags & EXT4_MB_STREAM_ALLOC) { - spin_lock(&sbi->s_md_lock); - sbi->s_mb_last_group = ac->ac_f_ex.fe_group; - sbi->s_mb_last_start = ac->ac_f_ex.fe_start; - spin_unlock(&sbi->s_md_lock); + int hash = ac->ac_inode->i_ino % sbi->s_mb_nr_global_goals; + + WRITE_ONCE(sbi->s_mb_last_groups[hash], ac->ac_f_ex.fe_group); } + /* * As we've just preallocated more space than * user requested originally, we store allocated @@ -2571,6 +2640,30 @@ void ext4_mb_scan_aligned(struct ext4_allocation_context *ac, } } +static void __ext4_mb_scan_group(struct ext4_allocation_context *ac) +{ + bool is_stripe_aligned; + struct ext4_sb_info *sbi; + enum criteria cr = ac->ac_criteria; + + ac->ac_groups_scanned++; + if (cr == CR_POWER2_ALIGNED) + return ext4_mb_simple_scan_group(ac, ac->ac_e4b); + + sbi = EXT4_SB(ac->ac_sb); + is_stripe_aligned = false; + if ((sbi->s_stripe >= sbi->s_cluster_ratio) && + !(ac->ac_g_ex.fe_len % EXT4_NUM_B2C(sbi, sbi->s_stripe))) + is_stripe_aligned = true; + + if ((cr == CR_GOAL_LEN_FAST || cr == CR_BEST_AVAIL_LEN) && + is_stripe_aligned) + ext4_mb_scan_aligned(ac, ac->ac_e4b); + + if (ac->ac_status == AC_STATUS_CONTINUE) + ext4_mb_complex_scan_group(ac, ac->ac_e4b); +} + /* * This is also called BEFORE we load the buddy bitmap. * Returns either 1 or 0 indicating that the group is either suitable @@ -2761,6 +2854,37 @@ ext4_group_t ext4_mb_prefetch(struct super_block *sb, ext4_group_t group, } /* + * Batch reads of the block allocation bitmaps to get + * multiple READs in flight; limit prefetching at inexpensive + * CR, otherwise mballoc can spend a lot of time loading + * imperfect groups + */ +static void ext4_mb_might_prefetch(struct ext4_allocation_context *ac, + ext4_group_t group) +{ + struct ext4_sb_info *sbi; + + if (ac->ac_prefetch_grp != group) + return; + + sbi = EXT4_SB(ac->ac_sb); + if (ext4_mb_cr_expensive(ac->ac_criteria) || + ac->ac_prefetch_ios < sbi->s_mb_prefetch_limit) { + unsigned int nr = sbi->s_mb_prefetch; + + if (ext4_has_feature_flex_bg(ac->ac_sb)) { + nr = 1 << sbi->s_log_groups_per_flex; + nr -= group & (nr - 1); + nr = umin(nr, sbi->s_mb_prefetch); + } + + ac->ac_prefetch_nr = nr; + ac->ac_prefetch_grp = ext4_mb_prefetch(ac->ac_sb, group, nr, + &ac->ac_prefetch_ios); + } +} + +/* * Prefetching reads the block bitmap into the buffer cache; but we * need to make sure that the buddy bitmap in the page cache has been * initialized. Note that ext4_mb_init_group() will block if the I/O @@ -2793,24 +2917,58 @@ void ext4_mb_prefetch_fini(struct super_block *sb, ext4_group_t group, } } +static int ext4_mb_scan_group(struct ext4_allocation_context *ac, + ext4_group_t group) +{ + int ret; + struct super_block *sb = ac->ac_sb; + enum criteria cr = ac->ac_criteria; + + ext4_mb_might_prefetch(ac, group); + + /* prevent unnecessary buddy loading. */ + if (cr < CR_ANY_FREE && spin_is_locked(ext4_group_lock_ptr(sb, group))) + return 0; + + /* This now checks without needing the buddy page */ + ret = ext4_mb_good_group_nolock(ac, group, cr); + if (ret <= 0) { + if (!ac->ac_first_err) + ac->ac_first_err = ret; + return 0; + } + + ret = ext4_mb_load_buddy(sb, group, ac->ac_e4b); + if (ret) + return ret; + + /* skip busy group */ + if (cr >= CR_ANY_FREE) + ext4_lock_group(sb, group); + else if (!ext4_try_lock_group(sb, group)) + goto out_unload; + + /* We need to check again after locking the block group. */ + if (unlikely(!ext4_mb_good_group(ac, group, cr))) + goto out_unlock; + + __ext4_mb_scan_group(ac); + +out_unlock: + ext4_unlock_group(sb, group); +out_unload: + ext4_mb_unload_buddy(ac->ac_e4b); + return ret; +} + static noinline_for_stack int ext4_mb_regular_allocator(struct ext4_allocation_context *ac) { - ext4_group_t prefetch_grp = 0, ngroups, group, i; - enum criteria new_cr, cr = CR_GOAL_LEN_FAST; - int err = 0, first_err = 0; - unsigned int nr = 0, prefetch_ios = 0; - struct ext4_sb_info *sbi; - struct super_block *sb; + ext4_group_t i; + int err = 0; + struct super_block *sb = ac->ac_sb; + struct ext4_sb_info *sbi = EXT4_SB(sb); struct ext4_buddy e4b; - int lost; - - sb = ac->ac_sb; - sbi = EXT4_SB(sb); - ngroups = ext4_get_groups_count(sb); - /* non-extent files are limited to low blocks/groups */ - if (!(ext4_test_inode_flag(ac->ac_inode, EXT4_INODE_EXTENTS))) - ngroups = sbi->s_blockfile_groups; BUG_ON(ac->ac_status == AC_STATUS_FOUND); @@ -2844,11 +3002,11 @@ ext4_mb_regular_allocator(struct ext4_allocation_context *ac) /* if stream allocation is enabled, use global goal */ if (ac->ac_flags & EXT4_MB_STREAM_ALLOC) { - /* TBD: may be hot point */ - spin_lock(&sbi->s_md_lock); - ac->ac_g_ex.fe_group = sbi->s_mb_last_group; - ac->ac_g_ex.fe_start = sbi->s_mb_last_start; - spin_unlock(&sbi->s_md_lock); + int hash = ac->ac_inode->i_ino % sbi->s_mb_nr_global_goals; + + ac->ac_g_ex.fe_group = READ_ONCE(sbi->s_mb_last_groups[hash]); + ac->ac_g_ex.fe_start = -1; + ac->ac_flags &= ~EXT4_MB_HINT_TRY_GOAL; } /* @@ -2856,107 +3014,21 @@ ext4_mb_regular_allocator(struct ext4_allocation_context *ac) * start with CR_GOAL_LEN_FAST, unless it is power of 2 * aligned, in which case let's do that faster approach first. */ + ac->ac_criteria = CR_GOAL_LEN_FAST; if (ac->ac_2order) - cr = CR_POWER2_ALIGNED; -repeat: - for (; cr < EXT4_MB_NUM_CRS && ac->ac_status == AC_STATUS_CONTINUE; cr++) { - ac->ac_criteria = cr; - /* - * searching for the right group start - * from the goal value specified - */ - group = ac->ac_g_ex.fe_group; - ac->ac_groups_linear_remaining = sbi->s_mb_max_linear_groups; - prefetch_grp = group; - nr = 0; - - for (i = 0, new_cr = cr; i < ngroups; i++, - ext4_mb_choose_next_group(ac, &new_cr, &group, ngroups)) { - int ret = 0; - - cond_resched(); - if (new_cr != cr) { - cr = new_cr; - goto repeat; - } - - /* - * Batch reads of the block allocation bitmaps - * to get multiple READs in flight; limit - * prefetching at inexpensive CR, otherwise mballoc - * can spend a lot of time loading imperfect groups - */ - if ((prefetch_grp == group) && - (ext4_mb_cr_expensive(cr) || - prefetch_ios < sbi->s_mb_prefetch_limit)) { - nr = sbi->s_mb_prefetch; - if (ext4_has_feature_flex_bg(sb)) { - nr = 1 << sbi->s_log_groups_per_flex; - nr -= group & (nr - 1); - nr = min(nr, sbi->s_mb_prefetch); - } - prefetch_grp = ext4_mb_prefetch(sb, group, - nr, &prefetch_ios); - } - - /* This now checks without needing the buddy page */ - ret = ext4_mb_good_group_nolock(ac, group, cr); - if (ret <= 0) { - if (!first_err) - first_err = ret; - continue; - } - - err = ext4_mb_load_buddy(sb, group, &e4b); - if (err) - goto out; - - ext4_lock_group(sb, group); - - /* - * We need to check again after locking the - * block group - */ - ret = ext4_mb_good_group(ac, group, cr); - if (ret == 0) { - ext4_unlock_group(sb, group); - ext4_mb_unload_buddy(&e4b); - continue; - } + ac->ac_criteria = CR_POWER2_ALIGNED; - ac->ac_groups_scanned++; - if (cr == CR_POWER2_ALIGNED) - ext4_mb_simple_scan_group(ac, &e4b); - else { - bool is_stripe_aligned = - (sbi->s_stripe >= - sbi->s_cluster_ratio) && - !(ac->ac_g_ex.fe_len % - EXT4_NUM_B2C(sbi, sbi->s_stripe)); - - if ((cr == CR_GOAL_LEN_FAST || - cr == CR_BEST_AVAIL_LEN) && - is_stripe_aligned) - ext4_mb_scan_aligned(ac, &e4b); - - if (ac->ac_status == AC_STATUS_CONTINUE) - ext4_mb_complex_scan_group(ac, &e4b); - } - - ext4_unlock_group(sb, group); - ext4_mb_unload_buddy(&e4b); - - if (ac->ac_status != AC_STATUS_CONTINUE) - break; - } - /* Processed all groups and haven't found blocks */ - if (sbi->s_mb_stats && i == ngroups) - atomic64_inc(&sbi->s_bal_cX_failed[cr]); + ac->ac_e4b = &e4b; + ac->ac_prefetch_ios = 0; + ac->ac_first_err = 0; +repeat: + while (ac->ac_criteria < EXT4_MB_NUM_CRS) { + err = ext4_mb_scan_groups(ac); + if (err) + goto out; - if (i == ngroups && ac->ac_criteria == CR_BEST_AVAIL_LEN) - /* Reset goal length to original goal length before - * falling into CR_GOAL_LEN_SLOW */ - ac->ac_g_ex.fe_len = ac->ac_orig_goal_len; + if (ac->ac_status != AC_STATUS_CONTINUE) + break; } if (ac->ac_b_ex.fe_len > 0 && ac->ac_status != AC_STATUS_FOUND && @@ -2967,6 +3039,8 @@ repeat: */ ext4_mb_try_best_found(ac, &e4b); if (ac->ac_status != AC_STATUS_FOUND) { + int lost; + /* * Someone more lucky has already allocated it. * The only thing we can do is just take first @@ -2982,23 +3056,27 @@ repeat: ac->ac_b_ex.fe_len = 0; ac->ac_status = AC_STATUS_CONTINUE; ac->ac_flags |= EXT4_MB_HINT_FIRST; - cr = CR_ANY_FREE; + ac->ac_criteria = CR_ANY_FREE; goto repeat; } } - if (sbi->s_mb_stats && ac->ac_status == AC_STATUS_FOUND) + if (sbi->s_mb_stats && ac->ac_status == AC_STATUS_FOUND) { atomic64_inc(&sbi->s_bal_cX_hits[ac->ac_criteria]); + if (ac->ac_flags & EXT4_MB_STREAM_ALLOC && + ac->ac_b_ex.fe_group == ac->ac_g_ex.fe_group) + atomic_inc(&sbi->s_bal_stream_goals); + } out: - if (!err && ac->ac_status != AC_STATUS_FOUND && first_err) - err = first_err; + if (!err && ac->ac_status != AC_STATUS_FOUND && ac->ac_first_err) + err = ac->ac_first_err; mb_debug(sb, "Best len %d, origin len %d, ac_status %u, ac_flags 0x%x, cr %d ret %d\n", ac->ac_b_ex.fe_len, ac->ac_o_ex.fe_len, ac->ac_status, - ac->ac_flags, cr, err); + ac->ac_flags, ac->ac_criteria, err); - if (nr) - ext4_mb_prefetch_fini(sb, prefetch_grp, nr); + if (ac->ac_prefetch_nr) + ext4_mb_prefetch_fini(sb, ac->ac_prefetch_grp, ac->ac_prefetch_nr); return err; } @@ -3121,8 +3199,6 @@ int ext4_seq_mb_stats_show(struct seq_file *seq, void *offset) atomic_read(&sbi->s_bal_cX_ex_scanned[CR_POWER2_ALIGNED])); seq_printf(seq, "\t\tuseless_loops: %llu\n", atomic64_read(&sbi->s_bal_cX_failed[CR_POWER2_ALIGNED])); - seq_printf(seq, "\t\tbad_suggestions: %u\n", - atomic_read(&sbi->s_bal_p2_aligned_bad_suggestions)); /* CR_GOAL_LEN_FAST stats */ seq_puts(seq, "\tcr_goal_fast_stats:\n"); @@ -3135,8 +3211,6 @@ int ext4_seq_mb_stats_show(struct seq_file *seq, void *offset) atomic_read(&sbi->s_bal_cX_ex_scanned[CR_GOAL_LEN_FAST])); seq_printf(seq, "\t\tuseless_loops: %llu\n", atomic64_read(&sbi->s_bal_cX_failed[CR_GOAL_LEN_FAST])); - seq_printf(seq, "\t\tbad_suggestions: %u\n", - atomic_read(&sbi->s_bal_goal_fast_bad_suggestions)); /* CR_BEST_AVAIL_LEN stats */ seq_puts(seq, "\tcr_best_avail_stats:\n"); @@ -3150,8 +3224,6 @@ int ext4_seq_mb_stats_show(struct seq_file *seq, void *offset) atomic_read(&sbi->s_bal_cX_ex_scanned[CR_BEST_AVAIL_LEN])); seq_printf(seq, "\t\tuseless_loops: %llu\n", atomic64_read(&sbi->s_bal_cX_failed[CR_BEST_AVAIL_LEN])); - seq_printf(seq, "\t\tbad_suggestions: %u\n", - atomic_read(&sbi->s_bal_best_avail_bad_suggestions)); /* CR_GOAL_LEN_SLOW stats */ seq_puts(seq, "\tcr_goal_slow_stats:\n"); @@ -3181,6 +3253,8 @@ int ext4_seq_mb_stats_show(struct seq_file *seq, void *offset) seq_printf(seq, "\textents_scanned: %u\n", atomic_read(&sbi->s_bal_ex_scanned)); seq_printf(seq, "\t\tgoal_hits: %u\n", atomic_read(&sbi->s_bal_goals)); + seq_printf(seq, "\t\tstream_goal_hits: %u\n", + atomic_read(&sbi->s_bal_stream_goals)); seq_printf(seq, "\t\tlen_goal_hits: %u\n", atomic_read(&sbi->s_bal_len_goals)); seq_printf(seq, "\t\t2^n_hits: %u\n", atomic_read(&sbi->s_bal_2orders)); @@ -3227,6 +3301,7 @@ static int ext4_mb_seq_structs_summary_show(struct seq_file *seq, void *v) unsigned long position = ((unsigned long) v); struct ext4_group_info *grp; unsigned int count; + unsigned long idx; position--; if (position >= MB_NUM_ORDERS(sb)) { @@ -3235,11 +3310,8 @@ static int ext4_mb_seq_structs_summary_show(struct seq_file *seq, void *v) seq_puts(seq, "avg_fragment_size_lists:\n"); count = 0; - read_lock(&sbi->s_mb_avg_fragment_size_locks[position]); - list_for_each_entry(grp, &sbi->s_mb_avg_fragment_size[position], - bb_avg_fragment_size_node) + xa_for_each(&sbi->s_mb_avg_fragment_size[position], idx, grp) count++; - read_unlock(&sbi->s_mb_avg_fragment_size_locks[position]); seq_printf(seq, "\tlist_order_%u_groups: %u\n", (unsigned int)position, count); return 0; @@ -3251,11 +3323,8 @@ static int ext4_mb_seq_structs_summary_show(struct seq_file *seq, void *v) seq_puts(seq, "max_free_order_lists:\n"); } count = 0; - read_lock(&sbi->s_mb_largest_free_orders_locks[position]); - list_for_each_entry(grp, &sbi->s_mb_largest_free_orders[position], - bb_largest_free_order_node) + xa_for_each(&sbi->s_mb_largest_free_orders[position], idx, grp) count++; - read_unlock(&sbi->s_mb_largest_free_orders_locks[position]); seq_printf(seq, "\tlist_order_%u_groups: %u\n", (unsigned int)position, count); @@ -3375,8 +3444,6 @@ int ext4_mb_add_groupinfo(struct super_block *sb, ext4_group_t group, INIT_LIST_HEAD(&meta_group_info[i]->bb_prealloc_list); init_rwsem(&meta_group_info[i]->alloc_sem); meta_group_info[i]->bb_free_root = RB_ROOT; - INIT_LIST_HEAD(&meta_group_info[i]->bb_largest_free_order_node); - INIT_LIST_HEAD(&meta_group_info[i]->bb_avg_fragment_size_node); meta_group_info[i]->bb_largest_free_order = -1; /* uninit */ meta_group_info[i]->bb_avg_fragment_size_order = -1; /* uninit */ meta_group_info[i]->bb_group = group; @@ -3586,6 +3653,20 @@ static void ext4_discard_work(struct work_struct *work) ext4_mb_unload_buddy(&e4b); } +static inline void ext4_mb_avg_fragment_size_destroy(struct ext4_sb_info *sbi) +{ + for (int i = 0; i < MB_NUM_ORDERS(sbi->s_sb); i++) + xa_destroy(&sbi->s_mb_avg_fragment_size[i]); + kfree(sbi->s_mb_avg_fragment_size); +} + +static inline void ext4_mb_largest_free_orders_destroy(struct ext4_sb_info *sbi) +{ + for (int i = 0; i < MB_NUM_ORDERS(sbi->s_sb); i++) + xa_destroy(&sbi->s_mb_largest_free_orders[i]); + kfree(sbi->s_mb_largest_free_orders); +} + int ext4_mb_init(struct super_block *sb) { struct ext4_sb_info *sbi = EXT4_SB(sb); @@ -3631,44 +3712,27 @@ int ext4_mb_init(struct super_block *sb) } while (i < MB_NUM_ORDERS(sb)); sbi->s_mb_avg_fragment_size = - kmalloc_array(MB_NUM_ORDERS(sb), sizeof(struct list_head), + kmalloc_array(MB_NUM_ORDERS(sb), sizeof(struct xarray), GFP_KERNEL); if (!sbi->s_mb_avg_fragment_size) { ret = -ENOMEM; goto out; } - sbi->s_mb_avg_fragment_size_locks = - kmalloc_array(MB_NUM_ORDERS(sb), sizeof(rwlock_t), - GFP_KERNEL); - if (!sbi->s_mb_avg_fragment_size_locks) { - ret = -ENOMEM; - goto out; - } - for (i = 0; i < MB_NUM_ORDERS(sb); i++) { - INIT_LIST_HEAD(&sbi->s_mb_avg_fragment_size[i]); - rwlock_init(&sbi->s_mb_avg_fragment_size_locks[i]); - } + for (i = 0; i < MB_NUM_ORDERS(sb); i++) + xa_init(&sbi->s_mb_avg_fragment_size[i]); + sbi->s_mb_largest_free_orders = - kmalloc_array(MB_NUM_ORDERS(sb), sizeof(struct list_head), + kmalloc_array(MB_NUM_ORDERS(sb), sizeof(struct xarray), GFP_KERNEL); if (!sbi->s_mb_largest_free_orders) { ret = -ENOMEM; goto out; } - sbi->s_mb_largest_free_orders_locks = - kmalloc_array(MB_NUM_ORDERS(sb), sizeof(rwlock_t), - GFP_KERNEL); - if (!sbi->s_mb_largest_free_orders_locks) { - ret = -ENOMEM; - goto out; - } - for (i = 0; i < MB_NUM_ORDERS(sb); i++) { - INIT_LIST_HEAD(&sbi->s_mb_largest_free_orders[i]); - rwlock_init(&sbi->s_mb_largest_free_orders_locks[i]); - } + for (i = 0; i < MB_NUM_ORDERS(sb); i++) + xa_init(&sbi->s_mb_largest_free_orders[i]); spin_lock_init(&sbi->s_md_lock); - sbi->s_mb_free_pending = 0; + atomic_set(&sbi->s_mb_free_pending, 0); INIT_LIST_HEAD(&sbi->s_freed_data_list[0]); INIT_LIST_HEAD(&sbi->s_freed_data_list[1]); INIT_LIST_HEAD(&sbi->s_discard_list); @@ -3709,10 +3773,19 @@ int ext4_mb_init(struct super_block *sb) sbi->s_mb_group_prealloc, EXT4_NUM_B2C(sbi, sbi->s_stripe)); } + sbi->s_mb_nr_global_goals = umin(num_possible_cpus(), + DIV_ROUND_UP(sbi->s_groups_count, 4)); + sbi->s_mb_last_groups = kcalloc(sbi->s_mb_nr_global_goals, + sizeof(ext4_group_t), GFP_KERNEL); + if (sbi->s_mb_last_groups == NULL) { + ret = -ENOMEM; + goto out; + } + sbi->s_locality_groups = alloc_percpu(struct ext4_locality_group); if (sbi->s_locality_groups == NULL) { ret = -ENOMEM; - goto out; + goto out_free_last_groups; } for_each_possible_cpu(i) { struct ext4_locality_group *lg; @@ -3737,11 +3810,12 @@ int ext4_mb_init(struct super_block *sb) out_free_locality_groups: free_percpu(sbi->s_locality_groups); sbi->s_locality_groups = NULL; +out_free_last_groups: + kfree(sbi->s_mb_last_groups); + sbi->s_mb_last_groups = NULL; out: - kfree(sbi->s_mb_avg_fragment_size); - kfree(sbi->s_mb_avg_fragment_size_locks); - kfree(sbi->s_mb_largest_free_orders); - kfree(sbi->s_mb_largest_free_orders_locks); + ext4_mb_avg_fragment_size_destroy(sbi); + ext4_mb_largest_free_orders_destroy(sbi); kfree(sbi->s_mb_offsets); sbi->s_mb_offsets = NULL; kfree(sbi->s_mb_maxs); @@ -3808,10 +3882,8 @@ void ext4_mb_release(struct super_block *sb) kvfree(group_info); rcu_read_unlock(); } - kfree(sbi->s_mb_avg_fragment_size); - kfree(sbi->s_mb_avg_fragment_size_locks); - kfree(sbi->s_mb_largest_free_orders); - kfree(sbi->s_mb_largest_free_orders_locks); + ext4_mb_avg_fragment_size_destroy(sbi); + ext4_mb_largest_free_orders_destroy(sbi); kfree(sbi->s_mb_offsets); kfree(sbi->s_mb_maxs); iput(sbi->s_buddy_cache); @@ -3841,6 +3913,7 @@ void ext4_mb_release(struct super_block *sb) } free_percpu(sbi->s_locality_groups); + kfree(sbi->s_mb_last_groups); } static inline int ext4_issue_discard(struct super_block *sb, @@ -3871,10 +3944,7 @@ static void ext4_free_data_in_buddy(struct super_block *sb, /* we expect to find existing buddy because it's pinned */ BUG_ON(err != 0); - spin_lock(&EXT4_SB(sb)->s_md_lock); - EXT4_SB(sb)->s_mb_free_pending -= entry->efd_count; - spin_unlock(&EXT4_SB(sb)->s_md_lock); - + atomic_sub(entry->efd_count, &EXT4_SB(sb)->s_mb_free_pending); db = e4b.bd_info; /* there are blocks to put in buddy to make them really free */ count += entry->efd_count; @@ -6278,28 +6348,63 @@ out: * are contiguous, AND the extents were freed by the same transaction, * AND the blocks are associated with the same group. */ -static void ext4_try_merge_freed_extent(struct ext4_sb_info *sbi, - struct ext4_free_data *entry, - struct ext4_free_data *new_entry, - struct rb_root *entry_rb_root) +static inline bool +ext4_freed_extents_can_be_merged(struct ext4_free_data *entry1, + struct ext4_free_data *entry2) { - if ((entry->efd_tid != new_entry->efd_tid) || - (entry->efd_group != new_entry->efd_group)) - return; - if (entry->efd_start_cluster + entry->efd_count == - new_entry->efd_start_cluster) { - new_entry->efd_start_cluster = entry->efd_start_cluster; - new_entry->efd_count += entry->efd_count; - } else if (new_entry->efd_start_cluster + new_entry->efd_count == - entry->efd_start_cluster) { - new_entry->efd_count += entry->efd_count; - } else - return; + if (entry1->efd_tid != entry2->efd_tid) + return false; + if (entry1->efd_start_cluster + entry1->efd_count != + entry2->efd_start_cluster) + return false; + if (WARN_ON_ONCE(entry1->efd_group != entry2->efd_group)) + return false; + return true; +} + +static inline void +ext4_merge_freed_extents(struct ext4_sb_info *sbi, struct rb_root *root, + struct ext4_free_data *entry1, + struct ext4_free_data *entry2) +{ + entry1->efd_count += entry2->efd_count; spin_lock(&sbi->s_md_lock); - list_del(&entry->efd_list); + list_del(&entry2->efd_list); spin_unlock(&sbi->s_md_lock); - rb_erase(&entry->efd_node, entry_rb_root); - kmem_cache_free(ext4_free_data_cachep, entry); + rb_erase(&entry2->efd_node, root); + kmem_cache_free(ext4_free_data_cachep, entry2); +} + +static inline void +ext4_try_merge_freed_extent_prev(struct ext4_sb_info *sbi, struct rb_root *root, + struct ext4_free_data *entry) +{ + struct ext4_free_data *prev; + struct rb_node *node; + + node = rb_prev(&entry->efd_node); + if (!node) + return; + + prev = rb_entry(node, struct ext4_free_data, efd_node); + if (ext4_freed_extents_can_be_merged(prev, entry)) + ext4_merge_freed_extents(sbi, root, prev, entry); +} + +static inline void +ext4_try_merge_freed_extent_next(struct ext4_sb_info *sbi, struct rb_root *root, + struct ext4_free_data *entry) +{ + struct ext4_free_data *next; + struct rb_node *node; + + node = rb_next(&entry->efd_node); + if (!node) + return; + + next = rb_entry(node, struct ext4_free_data, efd_node); + if (ext4_freed_extents_can_be_merged(entry, next)) + ext4_merge_freed_extents(sbi, root, entry, next); } static noinline_for_stack void @@ -6309,11 +6414,12 @@ ext4_mb_free_metadata(handle_t *handle, struct ext4_buddy *e4b, ext4_group_t group = e4b->bd_group; ext4_grpblk_t cluster; ext4_grpblk_t clusters = new_entry->efd_count; - struct ext4_free_data *entry; + struct ext4_free_data *entry = NULL; struct ext4_group_info *db = e4b->bd_info; struct super_block *sb = e4b->bd_sb; struct ext4_sb_info *sbi = EXT4_SB(sb); - struct rb_node **n = &db->bb_free_root.rb_node, *node; + struct rb_root *root = &db->bb_free_root; + struct rb_node **n = &root->rb_node; struct rb_node *parent = NULL, *new_node; BUG_ON(!ext4_handle_valid(handle)); @@ -6349,27 +6455,30 @@ ext4_mb_free_metadata(handle_t *handle, struct ext4_buddy *e4b, } } - rb_link_node(new_node, parent, n); - rb_insert_color(new_node, &db->bb_free_root); + atomic_add(clusters, &sbi->s_mb_free_pending); + if (!entry) + goto insert; - /* Now try to see the extent can be merged to left and right */ - node = rb_prev(new_node); - if (node) { - entry = rb_entry(node, struct ext4_free_data, efd_node); - ext4_try_merge_freed_extent(sbi, entry, new_entry, - &(db->bb_free_root)); + /* Now try to see the extent can be merged to prev and next */ + if (ext4_freed_extents_can_be_merged(new_entry, entry)) { + entry->efd_start_cluster = cluster; + entry->efd_count += new_entry->efd_count; + kmem_cache_free(ext4_free_data_cachep, new_entry); + ext4_try_merge_freed_extent_prev(sbi, root, entry); + return; } - - node = rb_next(new_node); - if (node) { - entry = rb_entry(node, struct ext4_free_data, efd_node); - ext4_try_merge_freed_extent(sbi, entry, new_entry, - &(db->bb_free_root)); + if (ext4_freed_extents_can_be_merged(entry, new_entry)) { + entry->efd_count += new_entry->efd_count; + kmem_cache_free(ext4_free_data_cachep, new_entry); + ext4_try_merge_freed_extent_next(sbi, root, entry); + return; } +insert: + rb_link_node(new_node, parent, n); + rb_insert_color(new_node, root); spin_lock(&sbi->s_md_lock); list_add_tail(&new_entry->efd_list, &sbi->s_freed_data_list[new_entry->efd_tid & 1]); - sbi->s_mb_free_pending += clusters; spin_unlock(&sbi->s_md_lock); } |