[PATCH] Revert: "f2fs: check last page index in cached bio to decide submission"

From: Chao Yu
Date: Wed Sep 26 2018 - 05:02:05 EST


There is one case that we can leave bio in f2fs, result in hanging
page writeback waiter.

Thread A Thread B
- f2fs_write_cache_pages
- f2fs_submit_page_write
page #0 cached in bio #0 of cold log
- f2fs_submit_page_write
page #1 cached in bio #1 of warm log
- f2fs_write_cache_pages
- f2fs_submit_page_write
bio is full, submit bio #1 contain page #1
- f2fs_submit_merged_write_cond(, page #1)
fail to submit bio #0 due to page #1 is not in any cached bios.

Signed-off-by: Chao Yu <yuchao0@xxxxxxxxxx>
---
fs/f2fs/checkpoint.c | 2 +-
fs/f2fs/data.c | 38 +++++++++++++++++++-------------------
fs/f2fs/f2fs.h | 4 ++--
fs/f2fs/node.c | 13 +++++++------
fs/f2fs/segment.c | 11 +++++------
5 files changed, 34 insertions(+), 34 deletions(-)

diff --git a/fs/f2fs/checkpoint.c b/fs/f2fs/checkpoint.c
index a34c3f8299f3..2ae02fbbcf56 100644
--- a/fs/f2fs/checkpoint.c
+++ b/fs/f2fs/checkpoint.c
@@ -280,7 +280,7 @@ static int __f2fs_write_meta_page(struct page *page,

if (wbc->for_reclaim)
f2fs_submit_merged_write_cond(sbi, page->mapping->host,
- 0, page->index, META);
+ page->index, 0, META);

unlock_page(page);

diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
index 59825c08eba0..56ac26dd1259 100644
--- a/fs/f2fs/data.c
+++ b/fs/f2fs/data.c
@@ -263,8 +263,8 @@ static void __submit_merged_bio(struct f2fs_bio_info *io)
io->bio = NULL;
}

-static bool __has_merged_page(struct f2fs_bio_info *io,
- struct inode *inode, nid_t ino, pgoff_t idx)
+static bool __has_merged_page(struct f2fs_bio_info *io, struct inode *inode,
+ struct page *page, nid_t ino)
{
struct bio_vec *bvec;
struct page *target;
@@ -273,7 +273,7 @@ static bool __has_merged_page(struct f2fs_bio_info *io,
if (!io->bio)
return false;

- if (!inode && !ino)
+ if (!inode && !page && !ino)
return true;

bio_for_each_segment_all(bvec, io->bio, i) {
@@ -283,11 +283,10 @@ static bool __has_merged_page(struct f2fs_bio_info *io,
else
target = fscrypt_control_page(bvec->bv_page);

- if (idx != target->index)
- continue;
-
if (inode && inode == target->mapping->host)
return true;
+ if (page && page == target)
+ return true;
if (ino && ino == ino_of_node(target))
return true;
}
@@ -296,7 +295,8 @@ static bool __has_merged_page(struct f2fs_bio_info *io,
}

static bool has_merged_page(struct f2fs_sb_info *sbi, struct inode *inode,
- nid_t ino, pgoff_t idx, enum page_type type)
+ struct page *page, nid_t ino,
+ enum page_type type)
{
enum page_type btype = PAGE_TYPE_OF_BIO(type);
enum temp_type temp;
@@ -307,7 +307,7 @@ static bool has_merged_page(struct f2fs_sb_info *sbi, struct inode *inode,
io = sbi->write_io[btype] + temp;

down_read(&io->io_rwsem);
- ret = __has_merged_page(io, inode, ino, idx);
+ ret = __has_merged_page(io, inode, page, ino);
up_read(&io->io_rwsem);

/* TODO: use HOT temp only for meta pages now. */
@@ -338,12 +338,12 @@ static void __f2fs_submit_merged_write(struct f2fs_sb_info *sbi,
}

static void __submit_merged_write_cond(struct f2fs_sb_info *sbi,
- struct inode *inode, nid_t ino, pgoff_t idx,
- enum page_type type, bool force)
+ struct inode *inode, struct page *page,
+ nid_t ino, enum page_type type, bool force)
{
enum temp_type temp;

- if (!force && !has_merged_page(sbi, inode, ino, idx, type))
+ if (!force && !has_merged_page(sbi, inode, page, ino, type))
return;

for (temp = HOT; temp < NR_TEMP_TYPE; temp++) {
@@ -362,10 +362,10 @@ void f2fs_submit_merged_write(struct f2fs_sb_info *sbi, enum page_type type)
}

void f2fs_submit_merged_write_cond(struct f2fs_sb_info *sbi,
- struct inode *inode, nid_t ino, pgoff_t idx,
- enum page_type type)
+ struct inode *inode, struct page *page,
+ nid_t ino, enum page_type type)
{
- __submit_merged_write_cond(sbi, inode, ino, idx, type, false);
+ __submit_merged_write_cond(sbi, inode, page, ino, type, false);
}

void f2fs_flush_merged_writes(struct f2fs_sb_info *sbi)
@@ -1885,7 +1885,7 @@ static int __write_data_page(struct page *page, bool *submitted,
ClearPageUptodate(page);

if (wbc->for_reclaim) {
- f2fs_submit_merged_write_cond(sbi, inode, 0, page->index, DATA);
+ f2fs_submit_merged_write_cond(sbi, inode, page->index, 0, DATA);
clear_inode_flag(inode, FI_HOT_DATA);
f2fs_remove_dirty_inode(inode);
submitted = NULL;
@@ -1943,10 +1943,10 @@ static int f2fs_write_cache_pages(struct address_space *mapping,
pgoff_t index;
pgoff_t end; /* Inclusive */
pgoff_t done_index;
- pgoff_t last_idx = ULONG_MAX;
int cycled;
int range_whole = 0;
int tag;
+ int nwritten = 0;

pagevec_init(&pvec, 0);

@@ -2047,7 +2047,7 @@ static int f2fs_write_cache_pages(struct address_space *mapping,
done = 1;
break;
} else if (submitted) {
- last_idx = page->index;
+ nwritten++;
}

if (--wbc->nr_to_write <= 0 &&
@@ -2069,9 +2069,9 @@ static int f2fs_write_cache_pages(struct address_space *mapping,
if (wbc->range_cyclic || (range_whole && wbc->nr_to_write > 0))
mapping->writeback_index = done_index;

- if (last_idx != ULONG_MAX)
+ if (nwritten)
f2fs_submit_merged_write_cond(F2FS_M_SB(mapping), mapping->host,
- 0, last_idx, DATA);
+ NULL, 0, DATA);

return ret;
}
diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index de1577d67dc3..04fc662bb108 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -3066,8 +3066,8 @@ void f2fs_destroy_checkpoint_caches(void);
*/
void f2fs_submit_merged_write(struct f2fs_sb_info *sbi, enum page_type type);
void f2fs_submit_merged_write_cond(struct f2fs_sb_info *sbi,
- struct inode *inode, nid_t ino, pgoff_t idx,
- enum page_type type);
+ struct inode *inode, struct page *page,
+ nid_t ino, enum page_type type);
void f2fs_flush_merged_writes(struct f2fs_sb_info *sbi);
int f2fs_submit_page_bio(struct f2fs_io_info *fio);
void f2fs_submit_page_write(struct f2fs_io_info *fio);
diff --git a/fs/f2fs/node.c b/fs/f2fs/node.c
index 313636b894b1..dafcd96514f0 100644
--- a/fs/f2fs/node.c
+++ b/fs/f2fs/node.c
@@ -1565,8 +1565,8 @@ static int __write_node_page(struct page *page, bool atomic, bool *submitted,
up_read(&sbi->node_write);

if (wbc->for_reclaim) {
- f2fs_submit_merged_write_cond(sbi, page->mapping->host, 0,
- page->index, NODE);
+ f2fs_submit_merged_write_cond(sbi, page->mapping->host,
+ page->index, 0, NODE);
submitted = NULL;
}

@@ -1638,12 +1638,13 @@ int f2fs_fsync_node_pages(struct f2fs_sb_info *sbi, struct inode *inode,
unsigned int *seq_id)
{
pgoff_t index, end;
- pgoff_t last_idx = ULONG_MAX;
struct pagevec pvec;
int ret = 0;
struct page *last_page = NULL;
bool marked = false;
nid_t ino = inode->i_ino;
+ int nr_pages;
+ int nwritten = 0;

if (atomic) {
last_page = last_fsync_dnode(sbi, ino);
@@ -1726,7 +1727,7 @@ int f2fs_fsync_node_pages(struct f2fs_sb_info *sbi, struct inode *inode,
f2fs_put_page(last_page, 0);
break;
} else if (submitted) {
- last_idx = page->index;
+ nwritten++;
}

if (page == last_page) {
@@ -1752,8 +1753,8 @@ int f2fs_fsync_node_pages(struct f2fs_sb_info *sbi, struct inode *inode,
goto retry;
}
out:
- if (last_idx != ULONG_MAX)
- f2fs_submit_merged_write_cond(sbi, NULL, ino, last_idx, NODE);
+ if (nwritten)
+ f2fs_submit_merged_write_cond(sbi, NULL, NULL, ino, NODE);
return ret ? -EIO: 0;
}

diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c
index 1bba85de54ff..3feef9965438 100644
--- a/fs/f2fs/segment.c
+++ b/fs/f2fs/segment.c
@@ -371,7 +371,7 @@ static int __f2fs_commit_inmem_pages(struct inode *inode)
.io_type = FS_DATA_IO,
};
struct list_head revoke_list;
- pgoff_t last_idx = ULONG_MAX;
+ bool submit_bio = false;
int err = 0;

INIT_LIST_HEAD(&revoke_list);
@@ -406,14 +406,14 @@ static int __f2fs_commit_inmem_pages(struct inode *inode)
}
/* record old blkaddr for revoking */
cur->old_addr = fio.old_blkaddr;
- last_idx = page->index;
+ submit_bio = true;
}
unlock_page(page);
list_move_tail(&cur->list, &revoke_list);
}

- if (last_idx != ULONG_MAX)
- f2fs_submit_merged_write_cond(sbi, inode, 0, last_idx, DATA);
+ if (submit_bio)
+ f2fs_submit_merged_write_cond(sbi, inode, NULL, 0, DATA);

if (err) {
/*
@@ -3218,8 +3218,7 @@ void f2fs_wait_on_page_writeback(struct page *page,
if (PageWriteback(page)) {
struct f2fs_sb_info *sbi = F2FS_P_SB(page);

- f2fs_submit_merged_write_cond(sbi, page->mapping->host,
- 0, page->index, type);
+ f2fs_submit_merged_write_cond(sbi, NULL, page, 0, type);
if (ordered)
wait_on_page_writeback(page);
else
--
2.18.0.rc1