[lustre-devel] [PATCH 16/22] ext4: add warning for directory htree growth
James Simmons
jsimmons at infradead.org
Sun Jul 21 18:23:45 PDT 2019
Signed-off-by: James Simmons <jsimmons at infradead.org>
---
fs/ext4/ext4.h | 1 +
fs/ext4/namei.c | 69 +++++++++++++++++++++++++++++++++++++++++++++++++++++++--
fs/ext4/super.c | 2 ++
fs/ext4/sysfs.c | 2 ++
4 files changed, 72 insertions(+), 2 deletions(-)
diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
index bf74c7c..5f73e19 100644
--- a/fs/ext4/ext4.h
+++ b/fs/ext4/ext4.h
@@ -1472,6 +1472,7 @@ struct ext4_sb_info {
unsigned int s_mb_group_prealloc;
unsigned long *s_mb_prealloc_table;
unsigned int s_max_dir_size_kb;
+ unsigned long s_warning_dir_size;
/* where last allocation was done - for stream allocation */
unsigned long s_mb_last_group;
unsigned long s_mb_last_start;
diff --git a/fs/ext4/namei.c b/fs/ext4/namei.c
index 1b6d22a..9b30cc6 100644
--- a/fs/ext4/namei.c
+++ b/fs/ext4/namei.c
@@ -757,12 +757,20 @@ struct ext4_dir_lock_data {
#define ext4_htree_lock_data(l) ((struct ext4_dir_lock_data *)(l)->lk_private)
#define ext4_find_entry(dir, name, dirent, inline) \
ext4_find_entry_locked(dir, name, dirent, inline, NULL)
-#define ext4_add_entry(handle, dentry, inode) \
- ext4_add_entry_locked(handle, dentry, inode, NULL)
/* NB: ext4_lblk_t is 32 bits so we use high bits to identify invalid blk */
#define EXT4_HTREE_NODE_CHANGED (0xcafeULL << 32)
+inline int ext4_add_entry(handle_t *handle, struct dentry *dentry,
+ struct inode *inode)
+{
+ int ret = ext4_add_entry_locked(handle, dentry, inode, NULL);
+
+ if (ret == -ENOBUFS)
+ ret = 0;
+ return ret;
+}
+
static void ext4_htree_event_cb(void *target, void *event)
{
u64 *block = (u64 *)target;
@@ -2612,6 +2620,55 @@ static int ext4_update_dotdot(handle_t *handle, struct dentry *dentry,
return err;
}
+static unsigned long __ext4_max_dir_size(struct dx_frame *frames,
+ struct dx_frame *frame,
+ struct inode *dir)
+{
+ unsigned long max_dir_size;
+
+ if (EXT4_SB(dir->i_sb)->s_max_dir_size_kb) {
+ max_dir_size = EXT4_SB(dir->i_sb)->s_max_dir_size_kb << 10;
+ } else {
+ max_dir_size = EXT4_BLOCK_SIZE(dir->i_sb);
+ while (frame >= frames) {
+ max_dir_size *= dx_get_limit(frame->entries);
+ if (frame == frames)
+ break;
+ frame--;
+ }
+ /* use 75% of max dir size in average */
+ max_dir_size = max_dir_size / 4 * 3;
+ }
+ return max_dir_size;
+}
+
+/*
+ * With hash tree growing, it is easy to hit ENOSPC, but it is hard
+ * to predict when it will happen. let's give administrators warning
+ * when reaching 3/5 and 2/3 of limit
+ */
+static inline bool dir_size_in_warning_range(struct dx_frame *frames,
+ struct dx_frame *frame,
+ struct inode *dir)
+{
+ struct super_block *sb = dir->i_sb;
+ unsigned long size1, size2;
+
+ if (unlikely(!EXT4_SB(sb)->s_warning_dir_size))
+ EXT4_SB(sb)->s_warning_dir_size =
+ __ext4_max_dir_size(frames, frame, dir);
+
+ size1 = EXT4_SB(sb)->s_warning_dir_size / 16 * 10;
+ size1 = size1 & ~(EXT4_BLOCK_SIZE(sb) - 1);
+ size2 = EXT4_SB(sb)->s_warning_dir_size / 16 * 11;
+ size2 = size2 & ~(EXT4_BLOCK_SIZE(sb) - 1);
+ if (in_range(dir->i_size, size1, EXT4_BLOCK_SIZE(sb)) ||
+ in_range(dir->i_size, size2, EXT4_BLOCK_SIZE(sb)))
+ return true;
+
+ return false;
+}
+
/*
* ext4_add_entry()
*
@@ -2739,6 +2796,7 @@ static int ext4_dx_add_entry(handle_t *handle, struct ext4_filename *fname,
struct buffer_head *bh;
struct super_block *sb = dir->i_sb;
struct ext4_dir_entry_2 *de;
+ bool ret_warn = false;
int restart;
int err;
@@ -2769,6 +2827,11 @@ static int ext4_dx_add_entry(handle_t *handle, struct ext4_filename *fname,
/* Block full, should compress but for now just split */
dxtrace(printk(KERN_DEBUG "using %u of %u node entries\n",
dx_get_count(entries), dx_get_limit(entries)));
+
+ if (frame - frames + 1 >= ext4_dir_htree_level(sb) ||
+ EXT4_SB(sb)->s_warning_dir_size)
+ ret_warn = dir_size_in_warning_range(frames, frame, dir);
+
/* Need to split index? */
if (dx_get_count(entries) == dx_get_limit(entries)) {
ext4_lblk_t newblock;
@@ -2935,6 +2998,8 @@ static int ext4_dx_add_entry(handle_t *handle, struct ext4_filename *fname,
*/
if (restart && err == 0)
goto again;
+ if (err == 0 && ret_warn)
+ err = -ENOBUFS;
return err;
}
diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index 07242d7..a3179b2 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -1901,6 +1901,8 @@ static int handle_mount_opt(struct super_block *sb, char *opt, int token,
sbi->s_li_wait_mult = arg;
} else if (token == Opt_max_dir_size_kb) {
sbi->s_max_dir_size_kb = arg;
+ /* reset s_warning_dir_size and make it re-calculated */
+ sbi->s_warning_dir_size = 0;
} else if (token == Opt_stripe) {
sbi->s_stripe = arg;
} else if (token == Opt_resuid) {
diff --git a/fs/ext4/sysfs.c b/fs/ext4/sysfs.c
index 3a71a16..575f318 100644
--- a/fs/ext4/sysfs.c
+++ b/fs/ext4/sysfs.c
@@ -182,6 +182,7 @@ static ssize_t journal_task_show(struct ext4_sb_info *sbi, char *buf)
EXT4_RW_ATTR_SBI_UI(inode_goal, s_inode_goal);
EXT4_RW_ATTR_SBI_UI(max_dir_size, s_max_dir_size_kb);
EXT4_RW_ATTR_SBI_UI(max_dir_size_kb, s_max_dir_size_kb);
+EXT4_RW_ATTR_SBI_UI(warning_dir_size, s_warning_dir_size);
EXT4_RW_ATTR_SBI_UI(mb_stats, s_mb_stats);
EXT4_RW_ATTR_SBI_UI(mb_max_to_scan, s_mb_max_to_scan);
EXT4_RW_ATTR_SBI_UI(mb_min_to_scan, s_mb_min_to_scan);
@@ -214,6 +215,7 @@ static ssize_t journal_task_show(struct ext4_sb_info *sbi, char *buf)
ATTR_LIST(inode_goal),
ATTR_LIST(max_dir_size),
ATTR_LIST(max_dir_size_kb),
+ ATTR_LIST(warning_dir_size),
ATTR_LIST(mb_stats),
ATTR_LIST(mb_max_to_scan),
ATTR_LIST(mb_min_to_scan),
--
1.8.3.1
More information about the lustre-devel
mailing list