f2fs: avoid sleeping under spin_lock

In the call trace below, we might sleep in function dput().

So in order to avoid sleeping under spin_lock, we remove f2fs_mark_inode_dirty_sync
from __try_update_largest_extent && __drop_largest_extent.

BUG: sleeping function called from invalid context at fs/dcache.c:796
Call trace:
	dump_backtrace+0x0/0x3f4
	show_stack+0x24/0x30
	dump_stack+0xe0/0x138
	___might_sleep+0x2a8/0x2c8
	__might_sleep+0x78/0x10c
	dput+0x7c/0x750
	block_dump___mark_inode_dirty+0x120/0x17c
	__mark_inode_dirty+0x344/0x11f0
	f2fs_mark_inode_dirty_sync+0x40/0x50
	__insert_extent_tree+0x2e0/0x2f4
	f2fs_update_extent_tree_range+0xcf4/0xde8
	f2fs_update_extent_cache+0x114/0x12c
	f2fs_update_data_blkaddr+0x40/0x50
	write_data_page+0x150/0x314
	do_write_data_page+0x648/0x2318
	__write_data_page+0xdb4/0x1640
	f2fs_write_cache_pages+0x768/0xafc
	__f2fs_write_data_pages+0x590/0x1218
	f2fs_write_data_pages+0x64/0x74
	do_writepages+0x74/0xe4
	__writeback_single_inode+0xdc/0x15f0
	writeback_sb_inodes+0x574/0xc98
	__writeback_inodes_wb+0x190/0x204
	wb_writeback+0x730/0xf14
	wb_check_old_data_flush+0x1bc/0x1c8
	wb_workfn+0x554/0xf74
	process_one_work+0x440/0x118c
	worker_thread+0xac/0x974
	kthread+0x1a0/0x1c8
	ret_from_fork+0x10/0x1c

Signed-off-by: Zhikang Zhang <zhangzhikang1@huawei.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This commit is contained in:
Zhikang Zhang 2018-09-10 16:18:25 +08:00 committed by Jaegeuk Kim
parent e1293bdfa0
commit b430f72636
2 changed files with 36 additions and 22 deletions

View File

@ -308,14 +308,13 @@ static unsigned int __free_extent_tree(struct f2fs_sb_info *sbi,
return count - atomic_read(&et->node_cnt);
}
static void __drop_largest_extent(struct inode *inode,
static void __drop_largest_extent(struct extent_tree *et,
pgoff_t fofs, unsigned int len)
{
struct extent_info *largest = &F2FS_I(inode)->extent_tree->largest;
if (fofs < largest->fofs + largest->len && fofs + len > largest->fofs) {
largest->len = 0;
f2fs_mark_inode_dirty_sync(inode, true);
if (fofs < et->largest.fofs + et->largest.len &&
fofs + len > et->largest.fofs) {
et->largest.len = 0;
et->largest_updated = true;
}
}
@ -416,12 +415,11 @@ out:
return ret;
}
static struct extent_node *__try_merge_extent_node(struct inode *inode,
static struct extent_node *__try_merge_extent_node(struct f2fs_sb_info *sbi,
struct extent_tree *et, struct extent_info *ei,
struct extent_node *prev_ex,
struct extent_node *next_ex)
{
struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
struct extent_node *en = NULL;
if (prev_ex && __is_back_mergeable(ei, &prev_ex->ei)) {
@ -443,7 +441,7 @@ static struct extent_node *__try_merge_extent_node(struct inode *inode,
if (!en)
return NULL;
__try_update_largest_extent(inode, et, en);
__try_update_largest_extent(et, en);
spin_lock(&sbi->extent_lock);
if (!list_empty(&en->list)) {
@ -454,12 +452,11 @@ static struct extent_node *__try_merge_extent_node(struct inode *inode,
return en;
}
static struct extent_node *__insert_extent_tree(struct inode *inode,
static struct extent_node *__insert_extent_tree(struct f2fs_sb_info *sbi,
struct extent_tree *et, struct extent_info *ei,
struct rb_node **insert_p,
struct rb_node *insert_parent)
{
struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
struct rb_node **p;
struct rb_node *parent = NULL;
struct extent_node *en = NULL;
@ -476,7 +473,7 @@ do_insert:
if (!en)
return NULL;
__try_update_largest_extent(inode, et, en);
__try_update_largest_extent(et, en);
/* update in global extent list */
spin_lock(&sbi->extent_lock);
@ -497,6 +494,7 @@ static void f2fs_update_extent_tree_range(struct inode *inode,
struct rb_node **insert_p = NULL, *insert_parent = NULL;
unsigned int end = fofs + len;
unsigned int pos = (unsigned int)fofs;
bool updated = false;
if (!et)
return;
@ -517,7 +515,7 @@ static void f2fs_update_extent_tree_range(struct inode *inode,
* drop largest extent before lookup, in case it's already
* been shrunk from extent tree
*/
__drop_largest_extent(inode, fofs, len);
__drop_largest_extent(et, fofs, len);
/* 1. lookup first extent node in range [fofs, fofs + len - 1] */
en = (struct extent_node *)f2fs_lookup_rb_tree_ret(&et->root,
@ -550,7 +548,7 @@ static void f2fs_update_extent_tree_range(struct inode *inode,
set_extent_info(&ei, end,
end - dei.fofs + dei.blk,
org_end - end);
en1 = __insert_extent_tree(inode, et, &ei,
en1 = __insert_extent_tree(sbi, et, &ei,
NULL, NULL);
next_en = en1;
} else {
@ -570,7 +568,7 @@ static void f2fs_update_extent_tree_range(struct inode *inode,
}
if (parts)
__try_update_largest_extent(inode, et, en);
__try_update_largest_extent(et, en);
else
__release_extent_node(sbi, et, en);
@ -590,15 +588,16 @@ static void f2fs_update_extent_tree_range(struct inode *inode,
if (blkaddr) {
set_extent_info(&ei, fofs, blkaddr, len);
if (!__try_merge_extent_node(inode, et, &ei, prev_en, next_en))
__insert_extent_tree(inode, et, &ei,
if (!__try_merge_extent_node(sbi, et, &ei, prev_en, next_en))
__insert_extent_tree(sbi, et, &ei,
insert_p, insert_parent);
/* give up extent_cache, if split and small updates happen */
if (dei.len >= 1 &&
prev.len < F2FS_MIN_EXTENT_LEN &&
et->largest.len < F2FS_MIN_EXTENT_LEN) {
__drop_largest_extent(inode, 0, UINT_MAX);
et->largest.len = 0;
et->largest_updated = true;
set_inode_flag(inode, FI_NO_EXTENT);
}
}
@ -606,7 +605,15 @@ static void f2fs_update_extent_tree_range(struct inode *inode,
if (is_inode_flag_set(inode, FI_NO_EXTENT))
__free_extent_tree(sbi, et);
if (et->largest_updated) {
et->largest_updated = false;
updated = true;
}
write_unlock(&et->lock);
if (updated)
f2fs_mark_inode_dirty_sync(inode, true);
}
unsigned int f2fs_shrink_extent_tree(struct f2fs_sb_info *sbi, int nr_shrink)
@ -705,6 +712,7 @@ void f2fs_drop_extent_tree(struct inode *inode)
{
struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
struct extent_tree *et = F2FS_I(inode)->extent_tree;
bool updated = false;
if (!f2fs_may_extent_tree(inode))
return;
@ -713,8 +721,13 @@ void f2fs_drop_extent_tree(struct inode *inode)
write_lock(&et->lock);
__free_extent_tree(sbi, et);
__drop_largest_extent(inode, 0, UINT_MAX);
if (et->largest.len) {
et->largest.len = 0;
updated = true;
}
write_unlock(&et->lock);
if (updated)
f2fs_mark_inode_dirty_sync(inode, true);
}
void f2fs_destroy_extent_tree(struct inode *inode)

View File

@ -572,6 +572,7 @@ struct extent_tree {
struct list_head list; /* to be used by sbi->zombie_list */
rwlock_t lock; /* protect extent info rb-tree */
atomic_t node_cnt; /* # of extent node in rb-tree*/
bool largest_updated; /* largest extent updated */
};
/*
@ -754,12 +755,12 @@ static inline bool __is_front_mergeable(struct extent_info *cur,
}
extern void f2fs_mark_inode_dirty_sync(struct inode *inode, bool sync);
static inline void __try_update_largest_extent(struct inode *inode,
struct extent_tree *et, struct extent_node *en)
static inline void __try_update_largest_extent(struct extent_tree *et,
struct extent_node *en)
{
if (en->ei.len > et->largest.len) {
et->largest = en->ei;
f2fs_mark_inode_dirty_sync(inode, true);
et->largest_updated = true;
}
}