diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h index 3b9ec24..64dc5fd 100644 --- a/fs/ext4/ext4.h +++ b/fs/ext4/ext4.h @@ -1450,6 +1450,9 @@ struct ext4_sb_info { unsigned int s_mb_min_to_scan; unsigned int s_mb_stats; unsigned int s_mb_order2_reqs; + ext4_fsblk_t s_mb_c1_blocks; + ext4_fsblk_t s_mb_c2_blocks; + ext4_fsblk_t s_mb_c3_blocks; unsigned long *s_mb_prealloc_table; unsigned int s_mb_group_prealloc; unsigned int s_max_dir_size_kb; @@ -1466,6 +1469,9 @@ struct ext4_sb_info { atomic_t s_bal_goals; /* goal hits */ atomic_t s_bal_breaks; /* too long searches */ atomic_t s_bal_2orders; /* 2^order hits */ + /* cX loop didn't find blocks */ + atomic64_t s_bal_cX_failed[3]; + atomic64_t s_bal_cX_skipped[3]; spinlock_t s_bal_lock; unsigned long s_mb_buddies_generated; unsigned long long s_mb_generation_time; @@ -2563,6 +2569,7 @@ extern void ext4_end_bitmap_read(struct buffer_head *bh, int uptodate); /* mballoc.c */ extern const struct file_operations ext4_seq_prealloc_table_fops; extern const struct seq_operations ext4_mb_seq_groups_ops; +extern const struct file_operations ext4_mb_seq_alloc_fops; extern const struct file_operations ext4_seq_mb_last_group_fops; extern int ext4_mb_seq_last_start_seq_show(struct seq_file *m, void *v); extern long ext4_mb_stats; diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c index 15c962f..7870406 100644 --- a/fs/ext4/mballoc.c +++ b/fs/ext4/mballoc.c @@ -2104,6 +2104,20 @@ static int ext4_mb_good_group(struct ext4_allocation_context *ac, return 0; } +static u64 available_blocks_count(struct ext4_sb_info *sbi) +{ + ext4_fsblk_t resv_blocks; + u64 bfree; + struct ext4_super_block *es = sbi->s_es; + + resv_blocks = EXT4_C2B(sbi, atomic64_read(&sbi->s_resv_clusters)); + bfree = percpu_counter_sum_positive(&sbi->s_freeclusters_counter) - + percpu_counter_sum_positive(&sbi->s_dirtyclusters_counter); + + bfree = EXT4_C2B(sbi, max_t(s64, bfree, 0)); + return bfree - (ext4_r_blocks_count(es) + resv_blocks); +} + static noinline_for_stack int ext4_mb_regular_allocator(struct ext4_allocation_context *ac) { @@ -2113,6 +2127,7 @@ ext4_mb_regular_allocator(struct ext4_allocation_context *ac) struct ext4_sb_info *sbi; struct super_block *sb; struct ext4_buddy e4b; + ext4_fsblk_t avail_blocks; sb = ac->ac_sb; sbi = EXT4_SB(sb); @@ -2165,6 +2180,21 @@ ext4_mb_regular_allocator(struct ext4_allocation_context *ac) /* Let's just scan groups to find more-less suitable blocks */ cr = ac->ac_2order ? 0 : 1; + + /* Choose what loop to pass based on disk fullness */ + avail_blocks = available_blocks_count(sbi) ; + + if (avail_blocks < sbi->s_mb_c3_blocks) { + cr = 3; + atomic64_inc(&sbi->s_bal_cX_skipped[2]); + } else if(avail_blocks < sbi->s_mb_c2_blocks) { + cr = 2; + atomic64_inc(&sbi->s_bal_cX_skipped[1]); + } else if(avail_blocks < sbi->s_mb_c1_blocks) { + cr = 1; + atomic64_inc(&sbi->s_bal_cX_skipped[0]); + } + /* * cr == 0 try to get exact allocation, * cr == 3 try to get anything @@ -2230,6 +2260,9 @@ repeat: if (ac->ac_status != AC_STATUS_CONTINUE) break; } + /* Processed all groups and haven't found blocks */ + if (i == ngroups) + atomic64_inc(&sbi->s_bal_cX_failed[cr]); } if (ac->ac_b_ex.fe_len > 0 && ac->ac_status != AC_STATUS_FOUND && @@ -2510,6 +2543,93 @@ const struct file_operations ext4_seq_mb_last_group_fops = { .write = ext4_mb_last_group_write, }; +static int mb_seq_alloc_show(struct seq_file *seq, void *v) +{ + struct super_block *sb = seq->private; + struct ext4_sb_info *sbi = EXT4_SB(sb); + + seq_printf(seq, "mballoc:\n"); + seq_printf(seq, "\tblocks: %u\n", atomic_read(&sbi->s_bal_allocated)); + seq_printf(seq, "\treqs: %u\n", atomic_read(&sbi->s_bal_reqs)); + seq_printf(seq, "\tsuccess: %u\n", atomic_read(&sbi->s_bal_success)); + + 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\t2^n_hits: %u\n", atomic_read(&sbi->s_bal_2orders)); + seq_printf(seq, "\t\tbreaks: %u\n", atomic_read(&sbi->s_bal_breaks)); + seq_printf(seq, "\t\tlost: %u\n", atomic_read(&sbi->s_mb_lost_chunks)); + + seq_printf(seq, "\tuseless_c1_loops: %llu\n", + atomic64_read(&sbi->s_bal_cX_failed[0])); + seq_printf(seq, "\tuseless_c2_loops: %llu\n", + atomic64_read(&sbi->s_bal_cX_failed[1])); + seq_printf(seq, "\tuseless_c3_loops: %llu\n", + atomic64_read(&sbi->s_bal_cX_failed[2])); + seq_printf(seq, "\tskipped_c1_loops: %llu\n", + atomic64_read(&sbi->s_bal_cX_skipped[0])); + seq_printf(seq, "\tskipped_c2_loops: %llu\n", + atomic64_read(&sbi->s_bal_cX_skipped[1])); + seq_printf(seq, "\tskipped_c3_loops: %llu\n", + atomic64_read(&sbi->s_bal_cX_skipped[2])); + seq_printf(seq, "\tbuddies_generated: %lu\n", + sbi->s_mb_buddies_generated); + seq_printf(seq, "\tbuddies_time_used: %llu\n", sbi->s_mb_generation_time); + seq_printf(seq, "\tpreallocated: %u\n", + atomic_read(&sbi->s_mb_preallocated)); + seq_printf(seq, "\tdiscarded: %u\n", + atomic_read(&sbi->s_mb_discarded)); + return 0; +} + +static ssize_t mb_seq_alloc_write(struct file *file, + const char __user *buf, + size_t cnt, loff_t *pos) +{ + struct ext4_sb_info *sbi = EXT4_SB(PDE_DATA(file_inode(file))); + + atomic_set(&sbi->s_bal_allocated, 0), + atomic_set(&sbi->s_bal_reqs, 0), + atomic_set(&sbi->s_bal_success, 0); + + atomic_set(&sbi->s_bal_ex_scanned, 0), + atomic_set(&sbi->s_bal_goals, 0), + atomic_set(&sbi->s_bal_2orders, 0), + atomic_set(&sbi->s_bal_breaks, 0), + atomic_set(&sbi->s_mb_lost_chunks, 0); + + atomic64_set(&sbi->s_bal_cX_failed[0], 0), + atomic64_set(&sbi->s_bal_cX_failed[1], 0), + atomic64_set(&sbi->s_bal_cX_failed[2], 0); + + atomic64_set(&sbi->s_bal_cX_skipped[0], 0), + atomic64_set(&sbi->s_bal_cX_skipped[1], 0), + atomic64_set(&sbi->s_bal_cX_skipped[2], 0); + + + sbi->s_mb_buddies_generated = 0; + sbi->s_mb_generation_time = 0; + + atomic_set(&sbi->s_mb_preallocated, 0), + atomic_set(&sbi->s_mb_discarded, 0); + + return cnt; +} + +static int mb_seq_alloc_open(struct inode *inode, struct file *file) +{ + return single_open(file, mb_seq_alloc_show, PDE_DATA(inode)); +} + +const struct file_operations ext4_mb_seq_alloc_fops = { + .owner = THIS_MODULE, + .open = mb_seq_alloc_open, + .read = seq_read, + .llseek = seq_lseek, + .release = single_release, + .write = mb_seq_alloc_write, +}; + int ext4_mb_seq_last_start_seq_show(struct seq_file *m, void *v) { struct ext4_sb_info *sbi = EXT4_SB(m->private); @@ -2734,6 +2854,7 @@ static int ext4_groupinfo_create_slab(size_t size) return 0; } +#define THRESHOLD_BLOCKS(ts) (ext4_blocks_count(sbi->s_es) / 100 * ts) int ext4_mb_init(struct super_block *sb) { struct ext4_sb_info *sbi = EXT4_SB(sb); @@ -2787,6 +2908,9 @@ int ext4_mb_init(struct super_block *sb) sbi->s_mb_min_to_scan = MB_DEFAULT_MIN_TO_SCAN; sbi->s_mb_stats = MB_DEFAULT_STATS; sbi->s_mb_order2_reqs = MB_DEFAULT_ORDER2_REQS; + sbi->s_mb_c1_blocks = THRESHOLD_BLOCKS(MB_DEFAULT_C1_THRESHOLD); + sbi->s_mb_c2_blocks = THRESHOLD_BLOCKS(MB_DEFAULT_C2_THRESHOLD); + sbi->s_mb_c3_blocks = THRESHOLD_BLOCKS(MB_DEFAULT_C3_THRESHOLD); /* * The default group preallocation is 512, which for 4k block * sizes translates to 2 megabytes. However for bigalloc file @@ -2922,6 +3046,16 @@ int ext4_mb_release(struct super_block *sb) atomic_read(&sbi->s_bal_allocated), atomic_read(&sbi->s_bal_reqs), atomic_read(&sbi->s_bal_success)); + ext4_msg(sb, KERN_INFO, + "mballoc: (%llu, %llu, %llu) useless c(0,1,2) loops", + atomic64_read(&sbi->s_bal_cX_failed[0]), + atomic64_read(&sbi->s_bal_cX_failed[1]), + atomic64_read(&sbi->s_bal_cX_failed[2])); + ext4_msg(sb, KERN_INFO, + "mballoc: (%llu, %llu, %llu) skipped c(0,1,2) loops", + atomic64_read(&sbi->s_bal_cX_skipped[0]), + atomic64_read(&sbi->s_bal_cX_skipped[1]), + atomic64_read(&sbi->s_bal_cX_skipped[2])); ext4_msg(sb, KERN_INFO, "mballoc: %u extents scanned, %u goal hits, " "%u 2^N hits, %u breaks, %u lost", diff --git a/fs/ext4/mballoc.h b/fs/ext4/mballoc.h index e00c3b7..d02daaf 100644 --- a/fs/ext4/mballoc.h +++ b/fs/ext4/mballoc.h @@ -72,6 +72,9 @@ do { \ * for which requests use 2^N search using buddies */ #define MB_DEFAULT_ORDER2_REQS 8 +#define MB_DEFAULT_C1_THRESHOLD 25 +#define MB_DEFAULT_C2_THRESHOLD 15 +#define MB_DEFAULT_C3_THRESHOLD 5 /* * default group prealloc size 512 blocks diff --git a/fs/ext4/sysfs.c b/fs/ext4/sysfs.c index 417b33a..f49821e 100644 --- a/fs/ext4/sysfs.c +++ b/fs/ext4/sysfs.c @@ -20,6 +20,9 @@ typedef enum { attr_noop, attr_delayed_allocation_blocks, + attr_mb_c1_threshold, + attr_mb_c2_threshold, + attr_mb_c3_threshold, attr_session_write_kbytes, attr_lifetime_write_kbytes, attr_reserved_clusters, @@ -134,6 +137,32 @@ static ssize_t journal_task_show(struct ext4_sb_info *sbi, char *buf) task_pid_vnr(sbi->s_journal->j_task)); } +#define THRESHOLD_PERCENT(ts) (ts * 100 / ext4_blocks_count(sbi->s_es)) + +static int save_threshold_percent(struct ext4_sb_info *sbi, const char *buf, + ext4_fsblk_t *blocks) +{ + unsigned long long val; + + int ret; + + ret = kstrtoull(skip_spaces(buf), 0, &val); + if (ret || val > 100) + return -EINVAL; + + *blocks = val * ext4_blocks_count(sbi->s_es) / 100; + return 0; +} + +static ssize_t mb_threshold_store(struct ext4_sb_info *sbi, + const char *buf, size_t count, + ext4_fsblk_t *blocks) +{ + int ret = save_threshold_percent(sbi, buf, blocks); + + return ret ?: count; +} + #define EXT4_ATTR(_name,_mode,_id) \ static struct ext4_attr ext4_attr_##_name = { \ .attr = {.name = __stringify(_name), .mode = _mode }, \ @@ -176,6 +205,9 @@ EXT4_ATTR_FUNC(delayed_allocation_blocks, 0444); EXT4_ATTR_FUNC(session_write_kbytes, 0444); EXT4_ATTR_FUNC(lifetime_write_kbytes, 0444); EXT4_ATTR_FUNC(reserved_clusters, 0644); +EXT4_ATTR_FUNC(mb_c1_threshold, 0644); +EXT4_ATTR_FUNC(mb_c2_threshold, 0644); +EXT4_ATTR_FUNC(mb_c3_threshold, 0644); EXT4_ATTR_OFFSET(inode_readahead_blks, 0644, inode_readahead, ext4_sb_info, s_inode_readahead_blks); @@ -211,6 +243,9 @@ static struct attribute *ext4_attrs[] = { ATTR_LIST(session_write_kbytes), ATTR_LIST(lifetime_write_kbytes), ATTR_LIST(reserved_clusters), + ATTR_LIST(mb_c1_threshold), + ATTR_LIST(mb_c2_threshold), + ATTR_LIST(mb_c3_threshold), ATTR_LIST(inode_readahead_blks), ATTR_LIST(inode_goal), ATTR_LIST(max_dir_size), @@ -294,6 +329,15 @@ static ssize_t ext4_attr_show(struct kobject *kobj, return snprintf(buf, PAGE_SIZE, "%llu\n", (s64) EXT4_C2B(sbi, percpu_counter_sum(&sbi->s_dirtyclusters_counter))); + case attr_mb_c1_threshold: + return scnprintf(buf, PAGE_SIZE, "%llu\n", + THRESHOLD_PERCENT(sbi->s_mb_c1_blocks)); + case attr_mb_c2_threshold: + return scnprintf(buf, PAGE_SIZE, "%llu\n", + THRESHOLD_PERCENT(sbi->s_mb_c2_blocks)); + case attr_mb_c3_threshold: + return scnprintf(buf, PAGE_SIZE, "%llu\n", + THRESHOLD_PERCENT(sbi->s_mb_c3_blocks)); case attr_session_write_kbytes: return session_write_kbytes_show(sbi, buf); case attr_lifetime_write_kbytes: @@ -363,6 +407,12 @@ static ssize_t ext4_attr_store(struct kobject *kobj, return inode_readahead_blks_store(sbi, buf, len); case attr_trigger_test_error: return trigger_test_error(sbi, buf, len); + case attr_mb_c1_threshold: + return mb_threshold_store(sbi, buf, len, &sbi->s_mb_c1_blocks); + case attr_mb_c2_threshold: + return mb_threshold_store(sbi, buf, len, &sbi->s_mb_c2_blocks); + case attr_mb_c3_threshold: + return mb_threshold_store(sbi, buf, len, &sbi->s_mb_c3_blocks); } return 0; } @@ -425,6 +475,8 @@ int ext4_register_sysfs(struct super_block *sb) &ext4_seq_mb_last_group_fops, sb); proc_create_single_data("mb_last_start", S_IRUGO, sbi->s_proc, ext4_mb_seq_last_start_seq_show, sb); + proc_create_data("mb_alloc_stats", S_IFREG | S_IRUGO | S_IWUSR, + sbi->s_proc, &ext4_mb_seq_alloc_fops, sb); } return 0; }