Re: [PATCH 2/2 v2] f2fs: avoid infinite loop to flush node pages

From: Jaegeuk Kim
Date: Thu Apr 14 2022 - 18:27:59 EST

xfstests/generic/475 can give EIO all the time which give an infinite loop
to flush node page like below. Let's avoid it.

[16418.518551] Call Trace:
[16418.518553] ? dm_submit_bio+0x48/0x400
[16418.518574] ? submit_bio_checks+0x1ac/0x5a0
[16418.525207] __submit_bio+0x1a9/0x230
[16418.525210] ? kmem_cache_alloc+0x29e/0x3c0
[16418.525223] submit_bio_noacct+0xa8/0x2b0
[16418.525226] submit_bio+0x4d/0x130
[16418.525238] __submit_bio+0x49/0x310 [f2fs]
[16418.525339] ? bio_add_page+0x6a/0x90
[16418.525344] f2fs_submit_page_bio+0x134/0x1f0 [f2fs]
[16418.525365] read_node_page+0x125/0x1b0 [f2fs]
[16418.525388] __get_node_page.part.0+0x58/0x3f0 [f2fs]
[16418.525409] __get_node_page+0x2f/0x60 [f2fs]
[16418.525431] f2fs_get_dnode_of_data+0x423/0x860 [f2fs]
[16418.525452] ? asm_sysvec_apic_timer_interrupt+0x12/0x20
[16418.525458] ? __mod_memcg_state.part.0+0x2a/0x30
[16418.525465] ? __mod_memcg_lruvec_state+0x27/0x40
[16418.525467] ? __xa_set_mark+0x57/0x70
[16418.525472] f2fs_do_write_data_page+0x10e/0x7b0 [f2fs]
[16418.525493] f2fs_write_single_data_page+0x555/0x830 [f2fs]
[16418.525514] ? sysvec_apic_timer_interrupt+0x4e/0x90
[16418.525518] ? asm_sysvec_apic_timer_interrupt+0x12/0x20
[16418.525523] f2fs_write_cache_pages+0x303/0x880 [f2fs]
[16418.525545] ? blk_flush_plug_list+0x47/0x100
[16418.525548] f2fs_write_data_pages+0xfd/0x320 [f2fs]
[16418.525569] do_writepages+0xd5/0x210
[16418.525648] filemap_fdatawrite_wbc+0x7d/0xc0
[16418.525655] filemap_fdatawrite+0x50/0x70
[16418.525658] f2fs_sync_dirty_inodes+0xa4/0x230 [f2fs]
[16418.525679] f2fs_write_checkpoint+0x16d/0x1720 [f2fs]
[16418.525699] ? ttwu_do_wakeup+0x1c/0x160
[16418.525709] ? ttwu_do_activate+0x6d/0xd0
[16418.525711] ? __wait_for_common+0x11d/0x150
[16418.525715] kill_f2fs_super+0xca/0x100 [f2fs]
[16418.525733] deactivate_locked_super+0x3b/0xb0
[16418.525739] deactivate_super+0x40/0x50
[16418.525741] cleanup_mnt+0x139/0x190
[16418.525747] __cleanup_mnt+0x12/0x20
[16418.525749] task_work_run+0x6d/0xa0
[16418.525765] exit_to_user_mode_prepare+0x1ad/0x1b0
[16418.525771] syscall_exit_to_user_mode+0x27/0x50
[16418.525774] do_syscall_64+0x48/0xc0
[16418.525776] entry_SYSCALL_64_after_hwframe+0x44/0xae

Signed-off-by: Jaegeuk Kim <jaegeuk@xxxxxxxxxx>
---

Change log from v1:
- cover one more error case

fs/f2fs/checkpoint.c | 8 +-------
fs/f2fs/f2fs.h | 20 ++++++++++++++++----
fs/f2fs/node.c | 2 ++
3 files changed, 19 insertions(+), 11 deletions(-)

diff --git a/fs/f2fs/checkpoint.c b/fs/f2fs/checkpoint.c
index 909085a78f9c..319903c2b34f 100644
--- a/fs/f2fs/checkpoint.c
+++ b/fs/f2fs/checkpoint.c
@@ -98,13 +98,7 @@ static struct page *__get_meta_page(struct f2fs_sb_info *sbi, pgoff_t index,
}

if (unlikely(!PageUptodate(page))) {
- if (page->index == sbi->metapage_eio_ofs) {
- if (sbi->metapage_eio_cnt++ == MAX_RETRY_META_PAGE_EIO)
- set_ckpt_flags(sbi, CP_ERROR_FLAG);
- } else {
- sbi->metapage_eio_ofs = page->index;
- sbi->metapage_eio_cnt = 0;
- }
+ f2fs_handle_page_eio(sbi, page->index, META);
f2fs_put_page(page, 1);
return ERR_PTR(-EIO);
}
diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index cd1e65bcf0b0..977826a22568 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -579,8 +579,8 @@ enum {
/* maximum retry quota flush count */
#define DEFAULT_RETRY_QUOTA_FLUSH_COUNT 8

-/* maximum retry of EIO'ed meta page */
-#define MAX_RETRY_META_PAGE_EIO 100
+/* maximum retry of EIO'ed page */
+#define MAX_RETRY_PAGE_EIO 100

#define F2FS_LINK_MAX 0xffffffff /* maximum link count per file */

@@ -1621,8 +1621,8 @@ struct f2fs_sb_info {
/* keep migration IO order for LFS mode */
struct f2fs_rwsem io_order_lock;
mempool_t *write_io_dummy; /* Dummy pages */
- pgoff_t metapage_eio_ofs; /* EIO page offset */
- int metapage_eio_cnt; /* EIO count */
+ pgoff_t page_eio_ofs[NR_PAGE_TYPE]; /* EIO page offset */
+ int page_eio_cnt[NR_PAGE_TYPE]; /* EIO count */

/* for checkpoint */
struct f2fs_checkpoint *ckpt; /* raw checkpoint pointer */
@@ -4543,6 +4543,18 @@ static inline void f2fs_io_schedule_timeout(long timeout)
io_schedule_timeout(timeout);
}

+static inline void f2fs_handle_page_eio(struct f2fs_sb_info *sbi, pgoff_t ofs,
+ enum page_type type)
+{
+ if (ofs == sbi->page_eio_ofs[type]) {
+ if (sbi->page_eio_cnt[type]++ == MAX_RETRY_PAGE_EIO)
+ set_ckpt_flags(sbi, CP_ERROR_FLAG);
+ } else {
+ sbi->page_eio_ofs[type] = ofs;
+ sbi->page_eio_cnt[type] = 0;
+ }
+}
+
#define EFSBADCRC EBADMSG /* Bad CRC detected */
#define EFSCORRUPTED EUCLEAN /* Filesystem is corrupted */

diff --git a/fs/f2fs/node.c b/fs/f2fs/node.c
index c45d341dcf6e..c280f482c741 100644
--- a/fs/f2fs/node.c
+++ b/fs/f2fs/node.c
@@ -1416,6 +1416,7 @@ static struct page *__get_node_page(struct f2fs_sb_info *sbi, pgoff_t nid,

err = read_node_page(page, 0);
if (err < 0) {
+ f2fs_handle_page_eio(sbi, page->index, NODE);
f2fs_put_page(page, 1);
return ERR_PTR(err);
} else if (err == LOCKED_PAGE) {
@@ -1452,6 +1453,7 @@ static struct page *__get_node_page(struct f2fs_sb_info *sbi, pgoff_t nid,
err = -EINVAL;
out_err:
ClearPageUptodate(page);
+ f2fs_handle_page_eio(sbi, page->index, NODE);
f2fs_put_page(page, 1);
return ERR_PTR(err);
}
--
2.36.0.rc0.470.gd361397f0d-goog