ext4: make trim/discard optional (and off by default)
It is anticipated that when sb_issue_discard starts doing real work on trim-capable devices, we may see issues. Make this mount-time optional, and default it to off until we know that things are working out OK. Signed-off-by: Eric Sandeen <sandeen@redhat.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
This commit is contained in:
parent
2bba702d4f
commit
5328e63531
|
@ -353,6 +353,12 @@ noauto_da_alloc replacing existing files via patterns such as
|
|||
system crashes before the delayed allocation
|
||||
blocks are forced to disk.
|
||||
|
||||
discard Controls whether ext4 should issue discard/TRIM
|
||||
nodiscard(*) commands to the underlying block device when
|
||||
blocks are freed. This is useful for SSD devices
|
||||
and sparse/thinly-provisioned LUNs, but it is off
|
||||
by default until sufficient testing has been done.
|
||||
|
||||
Data Mode
|
||||
=========
|
||||
There are 3 different data modes:
|
||||
|
|
|
@ -750,6 +750,7 @@ struct ext4_inode_info {
|
|||
#define EXT4_MOUNT_DELALLOC 0x8000000 /* Delalloc support */
|
||||
#define EXT4_MOUNT_DATA_ERR_ABORT 0x10000000 /* Abort on file data write */
|
||||
#define EXT4_MOUNT_BLOCK_VALIDITY 0x20000000 /* Block validity checking */
|
||||
#define EXT4_MOUNT_DISCARD 0x40000000 /* Issue DISCARD requests */
|
||||
|
||||
#define clear_opt(o, opt) o &= ~EXT4_MOUNT_##opt
|
||||
#define set_opt(o, opt) o |= EXT4_MOUNT_##opt
|
||||
|
|
|
@ -2529,7 +2529,6 @@ static void release_blocks_on_commit(journal_t *journal, transaction_t *txn)
|
|||
struct ext4_group_info *db;
|
||||
int err, count = 0, count2 = 0;
|
||||
struct ext4_free_data *entry;
|
||||
ext4_fsblk_t discard_block;
|
||||
struct list_head *l, *ltmp;
|
||||
|
||||
list_for_each_safe(l, ltmp, &txn->t_private_list) {
|
||||
|
@ -2559,13 +2558,19 @@ static void release_blocks_on_commit(journal_t *journal, transaction_t *txn)
|
|||
page_cache_release(e4b.bd_bitmap_page);
|
||||
}
|
||||
ext4_unlock_group(sb, entry->group);
|
||||
discard_block = (ext4_fsblk_t) entry->group * EXT4_BLOCKS_PER_GROUP(sb)
|
||||
+ entry->start_blk
|
||||
+ le32_to_cpu(EXT4_SB(sb)->s_es->s_first_data_block);
|
||||
trace_ext4_discard_blocks(sb, (unsigned long long)discard_block,
|
||||
entry->count);
|
||||
sb_issue_discard(sb, discard_block, entry->count);
|
||||
if (test_opt(sb, DISCARD)) {
|
||||
ext4_fsblk_t discard_block;
|
||||
struct ext4_super_block *es = EXT4_SB(sb)->s_es;
|
||||
|
||||
discard_block = (ext4_fsblk_t)entry->group *
|
||||
EXT4_BLOCKS_PER_GROUP(sb)
|
||||
+ entry->start_blk
|
||||
+ le32_to_cpu(es->s_first_data_block);
|
||||
trace_ext4_discard_blocks(sb,
|
||||
(unsigned long long)discard_block,
|
||||
entry->count);
|
||||
sb_issue_discard(sb, discard_block, entry->count);
|
||||
}
|
||||
kmem_cache_free(ext4_free_ext_cachep, entry);
|
||||
ext4_mb_release_desc(&e4b);
|
||||
}
|
||||
|
|
|
@ -899,6 +899,9 @@ static int ext4_show_options(struct seq_file *seq, struct vfsmount *vfs)
|
|||
if (test_opt(sb, NO_AUTO_DA_ALLOC))
|
||||
seq_puts(seq, ",noauto_da_alloc");
|
||||
|
||||
if (test_opt(sb, DISCARD))
|
||||
seq_puts(seq, ",discard");
|
||||
|
||||
ext4_show_quota_options(seq, sb);
|
||||
|
||||
return 0;
|
||||
|
@ -1079,7 +1082,8 @@ enum {
|
|||
Opt_usrquota, Opt_grpquota, Opt_i_version,
|
||||
Opt_stripe, Opt_delalloc, Opt_nodelalloc,
|
||||
Opt_block_validity, Opt_noblock_validity,
|
||||
Opt_inode_readahead_blks, Opt_journal_ioprio
|
||||
Opt_inode_readahead_blks, Opt_journal_ioprio,
|
||||
Opt_discard, Opt_nodiscard,
|
||||
};
|
||||
|
||||
static const match_table_t tokens = {
|
||||
|
@ -1144,6 +1148,8 @@ static const match_table_t tokens = {
|
|||
{Opt_auto_da_alloc, "auto_da_alloc=%u"},
|
||||
{Opt_auto_da_alloc, "auto_da_alloc"},
|
||||
{Opt_noauto_da_alloc, "noauto_da_alloc"},
|
||||
{Opt_discard, "discard"},
|
||||
{Opt_nodiscard, "nodiscard"},
|
||||
{Opt_err, NULL},
|
||||
};
|
||||
|
||||
|
@ -1565,6 +1571,12 @@ set_qf_format:
|
|||
else
|
||||
set_opt(sbi->s_mount_opt,NO_AUTO_DA_ALLOC);
|
||||
break;
|
||||
case Opt_discard:
|
||||
set_opt(sbi->s_mount_opt, DISCARD);
|
||||
break;
|
||||
case Opt_nodiscard:
|
||||
clear_opt(sbi->s_mount_opt, DISCARD);
|
||||
break;
|
||||
default:
|
||||
ext4_msg(sb, KERN_ERR,
|
||||
"Unrecognized mount option \"%s\" "
|
||||
|
|
Loading…
Reference in New Issue