subject:"\[PATCH 8\/8\] f2fs\: fix to avoid deadlock between checkpoint and writepages"

RE: [PATCH 8/8] f2fs: fix to avoid deadlock between checkpoint and writepages

2015-12-15 Thread Chao Yu

Hi Jaegeuk,

> -Original Message-
> From: Jaegeuk Kim [mailto:jaeg...@kernel.org]
> Sent: Wednesday, December 16, 2015 6:01 AM
> To: Chao Yu
> Cc: linux-f2fs-de...@lists.sourceforge.net; linux-kernel@vger.kernel.org
> Subject: Re: [PATCH 8/8] f2fs: fix to avoid deadlock between checkpoint and 
> writepages
> 
> Hi Chao,
> 
> On Tue, Dec 15, 2015 at 01:36:08PM +0800, Chao Yu wrote:
> > This patch fixes to move f2fs_balance_fs out of sbi->writepages'
> > coverage to avoid potential ABBA deadlock which was found by lockdep:
> >
> >   Possible unsafe locking scenario:
> >
> > CPU0CPU1
> > 
> >lock(>writepages);
> > lock(>cp_mutex);
> > lock(>writepages);
> >lock(>cp_mutex);
> >
> >   *** DEADLOCK ***
> 
> I expect it will be fine if syncing is done by f2fs_balance_fs_bg().

Yes, I will drop this patch.

Thanks,

> 
> Thanks,
> 
> >
> > stack of CPU0:
> > [] __lock_acquire+0x1321/0x1770
> > [] lock_acquire+0xb7/0x130
> > [] mutex_lock_nested+0x52/0x380
> > [] f2fs_balance_fs+0x8b/0xa0 [f2fs]
> > [] f2fs_write_data_page+0x33b/0x460 [f2fs]
> > [] __f2fs_writepage+0x1a/0x50 [f2fs]
> > [] T.1541+0x293/0x560 [f2fs]
> > [] f2fs_write_data_pages+0x12c/0x230 [f2fs]
> > [] do_writepages+0x23/0x40
> > [] __filemap_fdatawrite_range+0xb5/0xf0
> > [] filemap_write_and_wait_range+0xa3/0xd0
> > [] f2fs_symlink+0x180/0x300 [f2fs]
> > [] vfs_symlink+0xb7/0xe0
> > [] SyS_symlinkat+0xc5/0x100
> > [] SyS_symlink+0x16/0x20
> > [] entry_SYSCALL_64_fastpath+0x12/0x6f
> >
> > stack of CPU1
> > [] lock_acquire+0xb7/0x130
> > [] mutex_lock_nested+0x52/0x380
> > [] f2fs_write_data_pages+0x11e/0x230 [f2fs]
> > [] do_writepages+0x23/0x40
> > [] __filemap_fdatawrite_range+0xb5/0xf0
> > [] filemap_fdatawrite+0x1f/0x30
> > [] sync_dirty_inodes+0x4d/0xd0 [f2fs]
> > [] block_operations+0x71/0x160 [f2fs]
> > [] write_checkpoint+0xe8/0xbb0 [f2fs]
> > [] f2fs_sync_fs+0x8f/0xf0 [f2fs]
> > [] f2fs_balance_fs_bg+0x6f/0xd0 [f2fs]
> > [] f2fs_write_node_pages+0x57/0x150 [f2fs]
> > [] do_writepages+0x23/0x40
> > [] __writeback_single_inode+0x6d/0x3d0
> > [] writeback_sb_inodes+0x2c7/0x520
> > [] wb_writeback+0x133/0x330
> > [] wb_do_writeback+0xe8/0x270
> > [] wb_workfn+0x80/0x1f0
> > [] process_one_work+0x20c/0x5c0
> > [] worker_thread+0x132/0x5f0
> > [] kthread+0xde/0x100
> > [] ret_from_fork+0x3f/0x70
> >
> > Signed-off-by: Chao Yu 
> > ---
> >  fs/f2fs/data.c | 5 +++--
> >  1 file changed, 3 insertions(+), 2 deletions(-)
> >
> > diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
> > index 2e97057..985671d 100644
> > --- a/fs/f2fs/data.c
> > +++ b/fs/f2fs/data.c
> > @@ -506,7 +506,6 @@ static void __allocate_data_blocks(struct inode *inode, 
> > loff_t offset,
> > u64 end_offset;
> >
> > while (len) {
> > -   f2fs_balance_fs(sbi);
> > f2fs_lock_op(sbi);
> >
> > /* When reading holes, we need its node page */
> > @@ -1186,7 +1185,7 @@ out:
> > if (err)
> > ClearPageUptodate(page);
> > unlock_page(page);
> > -   if (need_balance_fs)
> > +   if (need_balance_fs && !test_opt(sbi, DATA_FLUSH))
> > f2fs_balance_fs(sbi);
> > if (wbc->for_reclaim) {
> > f2fs_submit_merged_bio(sbi, DATA, WRITE);
> > @@ -1617,6 +1616,8 @@ static ssize_t f2fs_direct_IO(struct kiocb *iocb, 
> > struct iov_iter *iter,
> > trace_f2fs_direct_IO_enter(inode, offset, count, rw);
> >
> > if (rw == WRITE) {
> > +   f2fs_balance_fs(sbi);
> > +
> > if (serialized)
> > mutex_lock(>writepages);
> > __allocate_data_blocks(inode, offset, count);
> > --
> > 2.6.3
> >

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Re: [PATCH 8/8] f2fs: fix to avoid deadlock between checkpoint and writepages

2015-12-15 Thread Jaegeuk Kim

Hi Chao,

On Tue, Dec 15, 2015 at 01:36:08PM +0800, Chao Yu wrote:
> This patch fixes to move f2fs_balance_fs out of sbi->writepages'
> coverage to avoid potential ABBA deadlock which was found by lockdep:
> 
>   Possible unsafe locking scenario:
> 
> CPU0CPU1
> 
>lock(>writepages);
> lock(>cp_mutex);
> lock(>writepages);
>lock(>cp_mutex);
> 
>   *** DEADLOCK ***

I expect it will be fine if syncing is done by f2fs_balance_fs_bg().

Thanks,

> 
> stack of CPU0:
> [] __lock_acquire+0x1321/0x1770
> [] lock_acquire+0xb7/0x130
> [] mutex_lock_nested+0x52/0x380
> [] f2fs_balance_fs+0x8b/0xa0 [f2fs]
> [] f2fs_write_data_page+0x33b/0x460 [f2fs]
> [] __f2fs_writepage+0x1a/0x50 [f2fs]
> [] T.1541+0x293/0x560 [f2fs]
> [] f2fs_write_data_pages+0x12c/0x230 [f2fs]
> [] do_writepages+0x23/0x40
> [] __filemap_fdatawrite_range+0xb5/0xf0
> [] filemap_write_and_wait_range+0xa3/0xd0
> [] f2fs_symlink+0x180/0x300 [f2fs]
> [] vfs_symlink+0xb7/0xe0
> [] SyS_symlinkat+0xc5/0x100
> [] SyS_symlink+0x16/0x20
> [] entry_SYSCALL_64_fastpath+0x12/0x6f
> 
> stack of CPU1
> [] lock_acquire+0xb7/0x130
> [] mutex_lock_nested+0x52/0x380
> [] f2fs_write_data_pages+0x11e/0x230 [f2fs]
> [] do_writepages+0x23/0x40
> [] __filemap_fdatawrite_range+0xb5/0xf0
> [] filemap_fdatawrite+0x1f/0x30
> [] sync_dirty_inodes+0x4d/0xd0 [f2fs]
> [] block_operations+0x71/0x160 [f2fs]
> [] write_checkpoint+0xe8/0xbb0 [f2fs]
> [] f2fs_sync_fs+0x8f/0xf0 [f2fs]
> [] f2fs_balance_fs_bg+0x6f/0xd0 [f2fs]
> [] f2fs_write_node_pages+0x57/0x150 [f2fs]
> [] do_writepages+0x23/0x40
> [] __writeback_single_inode+0x6d/0x3d0
> [] writeback_sb_inodes+0x2c7/0x520
> [] wb_writeback+0x133/0x330
> [] wb_do_writeback+0xe8/0x270
> [] wb_workfn+0x80/0x1f0
> [] process_one_work+0x20c/0x5c0
> [] worker_thread+0x132/0x5f0
> [] kthread+0xde/0x100
> [] ret_from_fork+0x3f/0x70
> 
> Signed-off-by: Chao Yu 
> ---
>  fs/f2fs/data.c | 5 +++--
>  1 file changed, 3 insertions(+), 2 deletions(-)
> 
> diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
> index 2e97057..985671d 100644
> --- a/fs/f2fs/data.c
> +++ b/fs/f2fs/data.c
> @@ -506,7 +506,6 @@ static void __allocate_data_blocks(struct inode *inode, 
> loff_t offset,
>   u64 end_offset;
>  
>   while (len) {
> - f2fs_balance_fs(sbi);
>   f2fs_lock_op(sbi);
>  
>   /* When reading holes, we need its node page */
> @@ -1186,7 +1185,7 @@ out:
>   if (err)
>   ClearPageUptodate(page);
>   unlock_page(page);
> - if (need_balance_fs)
> + if (need_balance_fs && !test_opt(sbi, DATA_FLUSH))
>   f2fs_balance_fs(sbi);
>   if (wbc->for_reclaim) {
>   f2fs_submit_merged_bio(sbi, DATA, WRITE);
> @@ -1617,6 +1616,8 @@ static ssize_t f2fs_direct_IO(struct kiocb *iocb, 
> struct iov_iter *iter,
>   trace_f2fs_direct_IO_enter(inode, offset, count, rw);
>  
>   if (rw == WRITE) {
> + f2fs_balance_fs(sbi);
> +
>   if (serialized)
>   mutex_lock(>writepages);
>   __allocate_data_blocks(inode, offset, count);
> -- 
> 2.6.3
> 
--
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Re: [PATCH 8/8] f2fs: fix to avoid deadlock between checkpoint and writepages

2015-12-15 Thread Jaegeuk Kim

Hi Chao,

On Tue, Dec 15, 2015 at 01:36:08PM +0800, Chao Yu wrote:
> This patch fixes to move f2fs_balance_fs out of sbi->writepages'
> coverage to avoid potential ABBA deadlock which was found by lockdep:
> 
>   Possible unsafe locking scenario:
> 
> CPU0CPU1
> 
>lock(>writepages);
> lock(>cp_mutex);
> lock(>writepages);
>lock(>cp_mutex);
> 
>   *** DEADLOCK ***

I expect it will be fine if syncing is done by f2fs_balance_fs_bg().

Thanks,

> 
> stack of CPU0:
> [] __lock_acquire+0x1321/0x1770
> [] lock_acquire+0xb7/0x130
> [] mutex_lock_nested+0x52/0x380
> [] f2fs_balance_fs+0x8b/0xa0 [f2fs]
> [] f2fs_write_data_page+0x33b/0x460 [f2fs]
> [] __f2fs_writepage+0x1a/0x50 [f2fs]
> [] T.1541+0x293/0x560 [f2fs]
> [] f2fs_write_data_pages+0x12c/0x230 [f2fs]
> [] do_writepages+0x23/0x40
> [] __filemap_fdatawrite_range+0xb5/0xf0
> [] filemap_write_and_wait_range+0xa3/0xd0
> [] f2fs_symlink+0x180/0x300 [f2fs]
> [] vfs_symlink+0xb7/0xe0
> [] SyS_symlinkat+0xc5/0x100
> [] SyS_symlink+0x16/0x20
> [] entry_SYSCALL_64_fastpath+0x12/0x6f
> 
> stack of CPU1
> [] lock_acquire+0xb7/0x130
> [] mutex_lock_nested+0x52/0x380
> [] f2fs_write_data_pages+0x11e/0x230 [f2fs]
> [] do_writepages+0x23/0x40
> [] __filemap_fdatawrite_range+0xb5/0xf0
> [] filemap_fdatawrite+0x1f/0x30
> [] sync_dirty_inodes+0x4d/0xd0 [f2fs]
> [] block_operations+0x71/0x160 [f2fs]
> [] write_checkpoint+0xe8/0xbb0 [f2fs]
> [] f2fs_sync_fs+0x8f/0xf0 [f2fs]
> [] f2fs_balance_fs_bg+0x6f/0xd0 [f2fs]
> [] f2fs_write_node_pages+0x57/0x150 [f2fs]
> [] do_writepages+0x23/0x40
> [] __writeback_single_inode+0x6d/0x3d0
> [] writeback_sb_inodes+0x2c7/0x520
> [] wb_writeback+0x133/0x330
> [] wb_do_writeback+0xe8/0x270
> [] wb_workfn+0x80/0x1f0
> [] process_one_work+0x20c/0x5c0
> [] worker_thread+0x132/0x5f0
> [] kthread+0xde/0x100
> [] ret_from_fork+0x3f/0x70
> 
> Signed-off-by: Chao Yu 
> ---
>  fs/f2fs/data.c | 5 +++--
>  1 file changed, 3 insertions(+), 2 deletions(-)
> 
> diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
> index 2e97057..985671d 100644
> --- a/fs/f2fs/data.c
> +++ b/fs/f2fs/data.c
> @@ -506,7 +506,6 @@ static void __allocate_data_blocks(struct inode *inode, 
> loff_t offset,
>   u64 end_offset;
>  
>   while (len) {
> - f2fs_balance_fs(sbi);
>   f2fs_lock_op(sbi);
>  
>   /* When reading holes, we need its node page */
> @@ -1186,7 +1185,7 @@ out:
>   if (err)
>   ClearPageUptodate(page);
>   unlock_page(page);
> - if (need_balance_fs)
> + if (need_balance_fs && !test_opt(sbi, DATA_FLUSH))
>   f2fs_balance_fs(sbi);
>   if (wbc->for_reclaim) {
>   f2fs_submit_merged_bio(sbi, DATA, WRITE);
> @@ -1617,6 +1616,8 @@ static ssize_t f2fs_direct_IO(struct kiocb *iocb, 
> struct iov_iter *iter,
>   trace_f2fs_direct_IO_enter(inode, offset, count, rw);
>  
>   if (rw == WRITE) {
> + f2fs_balance_fs(sbi);
> +
>   if (serialized)
>   mutex_lock(>writepages);
>   __allocate_data_blocks(inode, offset, count);
> -- 
> 2.6.3
> 
--
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RE: [PATCH 8/8] f2fs: fix to avoid deadlock between checkpoint and writepages

2015-12-15 Thread Chao Yu

Hi Jaegeuk,

> -Original Message-
> From: Jaegeuk Kim [mailto:jaeg...@kernel.org]
> Sent: Wednesday, December 16, 2015 6:01 AM
> To: Chao Yu
> Cc: linux-f2fs-de...@lists.sourceforge.net; linux-kernel@vger.kernel.org
> Subject: Re: [PATCH 8/8] f2fs: fix to avoid deadlock between checkpoint and 
> writepages
> 
> Hi Chao,
> 
> On Tue, Dec 15, 2015 at 01:36:08PM +0800, Chao Yu wrote:
> > This patch fixes to move f2fs_balance_fs out of sbi->writepages'
> > coverage to avoid potential ABBA deadlock which was found by lockdep:
> >
> >   Possible unsafe locking scenario:
> >
> > CPU0CPU1
> > 
> >lock(>writepages);
> > lock(>cp_mutex);
> > lock(>writepages);
> >lock(>cp_mutex);
> >
> >   *** DEADLOCK ***
> 
> I expect it will be fine if syncing is done by f2fs_balance_fs_bg().

Yes, I will drop this patch.

Thanks,

> 
> Thanks,
> 
> >
> > stack of CPU0:
> > [] __lock_acquire+0x1321/0x1770
> > [] lock_acquire+0xb7/0x130
> > [] mutex_lock_nested+0x52/0x380
> > [] f2fs_balance_fs+0x8b/0xa0 [f2fs]
> > [] f2fs_write_data_page+0x33b/0x460 [f2fs]
> > [] __f2fs_writepage+0x1a/0x50 [f2fs]
> > [] T.1541+0x293/0x560 [f2fs]
> > [] f2fs_write_data_pages+0x12c/0x230 [f2fs]
> > [] do_writepages+0x23/0x40
> > [] __filemap_fdatawrite_range+0xb5/0xf0
> > [] filemap_write_and_wait_range+0xa3/0xd0
> > [] f2fs_symlink+0x180/0x300 [f2fs]
> > [] vfs_symlink+0xb7/0xe0
> > [] SyS_symlinkat+0xc5/0x100
> > [] SyS_symlink+0x16/0x20
> > [] entry_SYSCALL_64_fastpath+0x12/0x6f
> >
> > stack of CPU1
> > [] lock_acquire+0xb7/0x130
> > [] mutex_lock_nested+0x52/0x380
> > [] f2fs_write_data_pages+0x11e/0x230 [f2fs]
> > [] do_writepages+0x23/0x40
> > [] __filemap_fdatawrite_range+0xb5/0xf0
> > [] filemap_fdatawrite+0x1f/0x30
> > [] sync_dirty_inodes+0x4d/0xd0 [f2fs]
> > [] block_operations+0x71/0x160 [f2fs]
> > [] write_checkpoint+0xe8/0xbb0 [f2fs]
> > [] f2fs_sync_fs+0x8f/0xf0 [f2fs]
> > [] f2fs_balance_fs_bg+0x6f/0xd0 [f2fs]
> > [] f2fs_write_node_pages+0x57/0x150 [f2fs]
> > [] do_writepages+0x23/0x40
> > [] __writeback_single_inode+0x6d/0x3d0
> > [] writeback_sb_inodes+0x2c7/0x520
> > [] wb_writeback+0x133/0x330
> > [] wb_do_writeback+0xe8/0x270
> > [] wb_workfn+0x80/0x1f0
> > [] process_one_work+0x20c/0x5c0
> > [] worker_thread+0x132/0x5f0
> > [] kthread+0xde/0x100
> > [] ret_from_fork+0x3f/0x70
> >
> > Signed-off-by: Chao Yu <chao2...@samsung.com>
> > ---
> >  fs/f2fs/data.c | 5 +++--
> >  1 file changed, 3 insertions(+), 2 deletions(-)
> >
> > diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
> > index 2e97057..985671d 100644
> > --- a/fs/f2fs/data.c
> > +++ b/fs/f2fs/data.c
> > @@ -506,7 +506,6 @@ static void __allocate_data_blocks(struct inode *inode, 
> > loff_t offset,
> > u64 end_offset;
> >
> > while (len) {
> > -   f2fs_balance_fs(sbi);
> > f2fs_lock_op(sbi);
> >
> > /* When reading holes, we need its node page */
> > @@ -1186,7 +1185,7 @@ out:
> > if (err)
> > ClearPageUptodate(page);
> > unlock_page(page);
> > -   if (need_balance_fs)
> > +   if (need_balance_fs && !test_opt(sbi, DATA_FLUSH))
> > f2fs_balance_fs(sbi);
> > if (wbc->for_reclaim) {
> > f2fs_submit_merged_bio(sbi, DATA, WRITE);
> > @@ -1617,6 +1616,8 @@ static ssize_t f2fs_direct_IO(struct kiocb *iocb, 
> > struct iov_iter *iter,
> > trace_f2fs_direct_IO_enter(inode, offset, count, rw);
> >
> > if (rw == WRITE) {
> > +   f2fs_balance_fs(sbi);
> > +
> > if (serialized)
> > mutex_lock(>writepages);
> > __allocate_data_blocks(inode, offset, count);
> > --
> > 2.6.3
> >

--
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[PATCH 8/8] f2fs: fix to avoid deadlock between checkpoint and writepages

2015-12-14 Thread Chao Yu

This patch fixes to move f2fs_balance_fs out of sbi->writepages'
coverage to avoid potential ABBA deadlock which was found by lockdep:

  Possible unsafe locking scenario:

CPU0CPU1

   lock(>writepages);
lock(>cp_mutex);
lock(>writepages);
   lock(>cp_mutex);

  *** DEADLOCK ***

stack of CPU0:
[] __lock_acquire+0x1321/0x1770
[] lock_acquire+0xb7/0x130
[] mutex_lock_nested+0x52/0x380
[] f2fs_balance_fs+0x8b/0xa0 [f2fs]
[] f2fs_write_data_page+0x33b/0x460 [f2fs]
[] __f2fs_writepage+0x1a/0x50 [f2fs]
[] T.1541+0x293/0x560 [f2fs]
[] f2fs_write_data_pages+0x12c/0x230 [f2fs]
[] do_writepages+0x23/0x40
[] __filemap_fdatawrite_range+0xb5/0xf0
[] filemap_write_and_wait_range+0xa3/0xd0
[] f2fs_symlink+0x180/0x300 [f2fs]
[] vfs_symlink+0xb7/0xe0
[] SyS_symlinkat+0xc5/0x100
[] SyS_symlink+0x16/0x20
[] entry_SYSCALL_64_fastpath+0x12/0x6f

stack of CPU1
[] lock_acquire+0xb7/0x130
[] mutex_lock_nested+0x52/0x380
[] f2fs_write_data_pages+0x11e/0x230 [f2fs]
[] do_writepages+0x23/0x40
[] __filemap_fdatawrite_range+0xb5/0xf0
[] filemap_fdatawrite+0x1f/0x30
[] sync_dirty_inodes+0x4d/0xd0 [f2fs]
[] block_operations+0x71/0x160 [f2fs]
[] write_checkpoint+0xe8/0xbb0 [f2fs]
[] f2fs_sync_fs+0x8f/0xf0 [f2fs]
[] f2fs_balance_fs_bg+0x6f/0xd0 [f2fs]
[] f2fs_write_node_pages+0x57/0x150 [f2fs]
[] do_writepages+0x23/0x40
[] __writeback_single_inode+0x6d/0x3d0
[] writeback_sb_inodes+0x2c7/0x520
[] wb_writeback+0x133/0x330
[] wb_do_writeback+0xe8/0x270
[] wb_workfn+0x80/0x1f0
[] process_one_work+0x20c/0x5c0
[] worker_thread+0x132/0x5f0
[] kthread+0xde/0x100
[] ret_from_fork+0x3f/0x70

Signed-off-by: Chao Yu 
---
 fs/f2fs/data.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
index 2e97057..985671d 100644
--- a/fs/f2fs/data.c
+++ b/fs/f2fs/data.c
@@ -506,7 +506,6 @@ static void __allocate_data_blocks(struct inode *inode, 
loff_t offset,
u64 end_offset;
 
while (len) {
-   f2fs_balance_fs(sbi);
f2fs_lock_op(sbi);
 
/* When reading holes, we need its node page */
@@ -1186,7 +1185,7 @@ out:
if (err)
ClearPageUptodate(page);
unlock_page(page);
-   if (need_balance_fs)
+   if (need_balance_fs && !test_opt(sbi, DATA_FLUSH))
f2fs_balance_fs(sbi);
if (wbc->for_reclaim) {
f2fs_submit_merged_bio(sbi, DATA, WRITE);
@@ -1617,6 +1616,8 @@ static ssize_t f2fs_direct_IO(struct kiocb *iocb, struct 
iov_iter *iter,
trace_f2fs_direct_IO_enter(inode, offset, count, rw);
 
if (rw == WRITE) {
+   f2fs_balance_fs(sbi);
+
if (serialized)
mutex_lock(>writepages);
__allocate_data_blocks(inode, offset, count);
-- 
2.6.3


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[PATCH 8/8] f2fs: fix to avoid deadlock between checkpoint and writepages

2015-12-14 Thread Chao Yu

This patch fixes to move f2fs_balance_fs out of sbi->writepages'
coverage to avoid potential ABBA deadlock which was found by lockdep:

  Possible unsafe locking scenario:

CPU0CPU1

   lock(>writepages);
lock(>cp_mutex);
lock(>writepages);
   lock(>cp_mutex);

  *** DEADLOCK ***

stack of CPU0:
[] __lock_acquire+0x1321/0x1770
[] lock_acquire+0xb7/0x130
[] mutex_lock_nested+0x52/0x380
[] f2fs_balance_fs+0x8b/0xa0 [f2fs]
[] f2fs_write_data_page+0x33b/0x460 [f2fs]
[] __f2fs_writepage+0x1a/0x50 [f2fs]
[] T.1541+0x293/0x560 [f2fs]
[] f2fs_write_data_pages+0x12c/0x230 [f2fs]
[] do_writepages+0x23/0x40
[] __filemap_fdatawrite_range+0xb5/0xf0
[] filemap_write_and_wait_range+0xa3/0xd0
[] f2fs_symlink+0x180/0x300 [f2fs]
[] vfs_symlink+0xb7/0xe0
[] SyS_symlinkat+0xc5/0x100
[] SyS_symlink+0x16/0x20
[] entry_SYSCALL_64_fastpath+0x12/0x6f

stack of CPU1
[] lock_acquire+0xb7/0x130
[] mutex_lock_nested+0x52/0x380
[] f2fs_write_data_pages+0x11e/0x230 [f2fs]
[] do_writepages+0x23/0x40
[] __filemap_fdatawrite_range+0xb5/0xf0
[] filemap_fdatawrite+0x1f/0x30
[] sync_dirty_inodes+0x4d/0xd0 [f2fs]
[] block_operations+0x71/0x160 [f2fs]
[] write_checkpoint+0xe8/0xbb0 [f2fs]
[] f2fs_sync_fs+0x8f/0xf0 [f2fs]
[] f2fs_balance_fs_bg+0x6f/0xd0 [f2fs]
[] f2fs_write_node_pages+0x57/0x150 [f2fs]
[] do_writepages+0x23/0x40
[] __writeback_single_inode+0x6d/0x3d0
[] writeback_sb_inodes+0x2c7/0x520
[] wb_writeback+0x133/0x330
[] wb_do_writeback+0xe8/0x270
[] wb_workfn+0x80/0x1f0
[] process_one_work+0x20c/0x5c0
[] worker_thread+0x132/0x5f0
[] kthread+0xde/0x100
[] ret_from_fork+0x3f/0x70

Signed-off-by: Chao Yu 
---
 fs/f2fs/data.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
index 2e97057..985671d 100644
--- a/fs/f2fs/data.c
+++ b/fs/f2fs/data.c
@@ -506,7 +506,6 @@ static void __allocate_data_blocks(struct inode *inode, 
loff_t offset,
u64 end_offset;
 
while (len) {
-   f2fs_balance_fs(sbi);
f2fs_lock_op(sbi);
 
/* When reading holes, we need its node page */
@@ -1186,7 +1185,7 @@ out:
if (err)
ClearPageUptodate(page);
unlock_page(page);
-   if (need_balance_fs)
+   if (need_balance_fs && !test_opt(sbi, DATA_FLUSH))
f2fs_balance_fs(sbi);
if (wbc->for_reclaim) {
f2fs_submit_merged_bio(sbi, DATA, WRITE);
@@ -1617,6 +1616,8 @@ static ssize_t f2fs_direct_IO(struct kiocb *iocb, struct 
iov_iter *iter,
trace_f2fs_direct_IO_enter(inode, offset, count, rw);
 
if (rw == WRITE) {
+   f2fs_balance_fs(sbi);
+
if (serialized)
mutex_lock(>writepages);
__allocate_data_blocks(inode, offset, count);
-- 
2.6.3


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RE: [PATCH 8/8] f2fs: fix to avoid deadlock between checkpoint and writepages

Re: [PATCH 8/8] f2fs: fix to avoid deadlock between checkpoint and writepages

Re: [PATCH 8/8] f2fs: fix to avoid deadlock between checkpoint and writepages

RE: [PATCH 8/8] f2fs: fix to avoid deadlock between checkpoint and writepages

[PATCH 8/8] f2fs: fix to avoid deadlock between checkpoint and writepages

[PATCH 8/8] f2fs: fix to avoid deadlock between checkpoint and writepages

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