Re: [PATCH 1/2] f2fs: fix to commit bio cache after flushing node pages
On Thu, Sep 29, 2016 at 06:45:03PM +0800, Chao Yu wrote:
> On 2016/9/29 4:19, Jaegeuk Kim wrote:
> > On Tue, Sep 27, 2016 at 10:09:03AM +0800, Chao Yu wrote:
> >> On 2016/9/27 9:39, Jaegeuk Kim wrote:
> >>> On Tue, Sep 27, 2016 at 08:57:41AM +0800, Chao Yu wrote:
> Hi Jaegeuk,
>
> On 2016/9/27 2:33, Jaegeuk Kim wrote:
> > Hi Chao,
> >
> > On Tue, Sep 27, 2016 at 12:09:52AM +0800, Chao Yu wrote:
> >> From: Chao Yu
> >>
> >> In sync_node_pages, we won't check and commit last merged pages in
> >> private
> >> bio cache of f2fs, as these pages were taged as writeback, someone who
> >> is
> >> waiting for writebacking of the page will be blocked until the cache
> >> was
> >> committed by someone else.
> >>
> >> We need to commit node type bio cache to avoid potential deadlock or
> >> long
> >> delay of waiting writeback.
> >>
> >> Signed-off-by: Chao Yu
> >> ---
> >> fs/f2fs/node.c | 11 +--
> >> 1 file changed, 9 insertions(+), 2 deletions(-)
> >>
> >> diff --git a/fs/f2fs/node.c b/fs/f2fs/node.c
> >> index 9faddcd..f73f774 100644
> >> --- a/fs/f2fs/node.c
> >> +++ b/fs/f2fs/node.c
> >> @@ -1416,6 +1416,7 @@ int sync_node_pages(struct f2fs_sb_info *sbi,
> >> struct writeback_control *wbc)
> >>struct pagevec pvec;
> >>int step = 0;
> >>int nwritten = 0;
> >> + int ret = 0;
> >>
> >>pagevec_init(&pvec, 0);
> >>
> >> @@ -1436,7 +1437,8 @@ next_step:
> >>
> >>if (unlikely(f2fs_cp_error(sbi))) {
> >>pagevec_release(&pvec);
> >> - return -EIO;
> >> + ret = -EIO;
> >> + goto out;
> >>}
> >>
> >>/*
> >> @@ -1487,6 +1489,8 @@ continue_unlock:
> >>
> >>if (NODE_MAPPING(sbi)->a_ops->writepage(page,
> >> wbc))
> >>unlock_page(page);
> >> + else
> >> + nwritten++;
> >>
> >>if (--wbc->nr_to_write == 0)
> >>break;
> >> @@ -1504,7 +1508,10 @@ continue_unlock:
> >>step++;
> >>goto next_step;
> >>}
> >> - return nwritten;
> >> +out:
> >> + if (nwritten)
> >> + f2fs_submit_merged_bio(sbi, NODE, WRITE);
> >
> > IIRC, we don't need to flush this, since f2fs_submit_merged_bio_cond()
> > would
> > handle this in f2fs_wait_on_page_writeback().
>
> Yes, it covers all the cases in f2fs private codes, but there are still
> some
> codes in mm or fs directory, and they didn't use
> f2fs_wait_on_page_writeback
> when waiting page writeback. Such as do_writepages && filemap_fdatawait
> in
> __writeback_single_inode...
> >>>
> >>> The do_writepages() is okay, which will call f2fs_write_node_pages().
> >>> The __writeback_single_inode() won't do filemap_fdatawait() with
> >>> WB_SYNC_ALL.
> >>> We don't need to take care of truncation as well.
> >>>
> >>> Any missing one?
> >>
> >> Another is: while testing with first version of checkpoint error
> >> injection, I
> >> encounter below dump stack:
> >>
> >> "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
> >> mount D 8801c1bf7960 0 97685 97397 0x0008
> >> 8801c1bf7960 8801c1bf7930 88017590 8801c1bf7980
> >> 8801c1bf8000 7fff 88021f7be340
> >> 817c8880 8801c1bf7978 817c80a5 880214f58fc0
> >> Call Trace:
> >> [] ? bit_wait+0x50/0x50
> >> [] schedule+0x35/0x80
> >> [] schedule_timeout+0x292/0x3d0
> >> [] ? xen_clocksource_get_cycles+0x15/0x20
> >> [] ? ktime_get+0x3c/0xb0
> >> [] ? bit_wait+0x50/0x50
> >> [] io_schedule_timeout+0xa6/0x110
> >> [] bit_wait_io+0x1b/0x60
> >> [] __wait_on_bit+0x64/0x90
> >> [] wait_on_page_bit+0xc4/0xd0
> >> [] ? autoremove_wake_function+0x40/0x40
> >> [] truncate_inode_pages_range+0x409/0x840
> >> [] ? pcpu_free_area+0x13d/0x1a0
> >> [] ? wake_up_bit+0x25/0x30
> >> [] truncate_inode_pages_final+0x4c/0x60
> >> [] f2fs_evict_inode+0x48/0x390 [f2fs]
> >> [] evict+0xc7/0x1a0
> >> [] iput+0x197/0x200
> >> [] f2fs_fill_super+0xab2/0x1130 [f2fs]
> >> [] mount_bdev+0x184/0x1c0
> >> [] ? f2fs_commit_super+0x100/0x100 [f2fs]
> >> [] f2fs_mount+0x15/0x20 [f2fs]
> >> [] mount_fs+0x39/0x160
> >> [] vfs_kern_mount+0x67/0x110
> >> [] do_mount+0x1bb/0xc80
> >> [] SyS_mount+0x83/0xd0
> >> [] do_syscall_64+0x6e/0x170
> >> [] entry_SYSCALL64_slow_path+0x25/0x25
> >>
> >> Any thoughts?
> >
> > I think this should not happen normall
[PATCH 1/2] f2fs: fix to commit bio cache after flushing node pages
In sync_node_pages, we won't check and commit last merged pages in private
bio cache of f2fs, as these pages were taged as writeback, someone who is
waiting for writebacking of the page will be blocked until the cache was
committed by someone else.
We need to commit node type bio cache to avoid potential deadlock or long
delay of waiting writeback.
Signed-off-by: Chao Yu
---
fs/f2fs/node.c | 18 --
1 file changed, 16 insertions(+), 2 deletions(-)
diff --git a/fs/f2fs/node.c b/fs/f2fs/node.c
index 9faddcd..8831035 100644
--- a/fs/f2fs/node.c
+++ b/fs/f2fs/node.c
@@ -1312,6 +1312,7 @@ int fsync_node_pages(struct f2fs_sb_info *sbi, struct
inode *inode,
struct page *last_page = NULL;
bool marked = false;
nid_t ino = inode->i_ino;
+ int nwritten = 0;
if (atomic) {
last_page = last_fsync_dnode(sbi, ino);
@@ -1385,7 +1386,10 @@ continue_unlock:
unlock_page(page);
f2fs_put_page(last_page, 0);
break;
+ } else {
+ nwritten++;
}
+
if (page == last_page) {
f2fs_put_page(page, 0);
marked = true;
@@ -1407,6 +1411,9 @@ continue_unlock:
unlock_page(last_page);
goto retry;
}
+
+ if (nwritten)
+ f2fs_submit_merged_bio_cond(sbi, NULL, NULL, ino, NODE, WRITE);
return ret ? -EIO: 0;
}
@@ -1416,6 +1423,7 @@ int sync_node_pages(struct f2fs_sb_info *sbi, struct
writeback_control *wbc)
struct pagevec pvec;
int step = 0;
int nwritten = 0;
+ int ret = 0;
pagevec_init(&pvec, 0);
@@ -1436,7 +1444,8 @@ next_step:
if (unlikely(f2fs_cp_error(sbi))) {
pagevec_release(&pvec);
- return -EIO;
+ ret = -EIO;
+ goto out;
}
/*
@@ -1487,6 +1496,8 @@ continue_unlock:
if (NODE_MAPPING(sbi)->a_ops->writepage(page, wbc))
unlock_page(page);
+ else
+ nwritten++;
if (--wbc->nr_to_write == 0)
break;
@@ -1504,7 +1515,10 @@ continue_unlock:
step++;
goto next_step;
}
- return nwritten;
+out:
+ if (nwritten)
+ f2fs_submit_merged_bio(sbi, NODE, WRITE);
+ return ret;
}
int wait_on_node_pages_writeback(struct f2fs_sb_info *sbi, nid_t ino)
--
2.8.2.311.gee88674
Re: [PATCH 1/2] f2fs: fix to commit bio cache after flushing node pages
On 2016/9/29 4:19, Jaegeuk Kim wrote:
> On Tue, Sep 27, 2016 at 10:09:03AM +0800, Chao Yu wrote:
>> On 2016/9/27 9:39, Jaegeuk Kim wrote:
>>> On Tue, Sep 27, 2016 at 08:57:41AM +0800, Chao Yu wrote:
Hi Jaegeuk,
On 2016/9/27 2:33, Jaegeuk Kim wrote:
> Hi Chao,
>
> On Tue, Sep 27, 2016 at 12:09:52AM +0800, Chao Yu wrote:
>> From: Chao Yu
>>
>> In sync_node_pages, we won't check and commit last merged pages in
>> private
>> bio cache of f2fs, as these pages were taged as writeback, someone who is
>> waiting for writebacking of the page will be blocked until the cache was
>> committed by someone else.
>>
>> We need to commit node type bio cache to avoid potential deadlock or long
>> delay of waiting writeback.
>>
>> Signed-off-by: Chao Yu
>> ---
>> fs/f2fs/node.c | 11 +--
>> 1 file changed, 9 insertions(+), 2 deletions(-)
>>
>> diff --git a/fs/f2fs/node.c b/fs/f2fs/node.c
>> index 9faddcd..f73f774 100644
>> --- a/fs/f2fs/node.c
>> +++ b/fs/f2fs/node.c
>> @@ -1416,6 +1416,7 @@ int sync_node_pages(struct f2fs_sb_info *sbi,
>> struct writeback_control *wbc)
>> struct pagevec pvec;
>> int step = 0;
>> int nwritten = 0;
>> +int ret = 0;
>>
>> pagevec_init(&pvec, 0);
>>
>> @@ -1436,7 +1437,8 @@ next_step:
>>
>> if (unlikely(f2fs_cp_error(sbi))) {
>> pagevec_release(&pvec);
>> -return -EIO;
>> +ret = -EIO;
>> +goto out;
>> }
>>
>> /*
>> @@ -1487,6 +1489,8 @@ continue_unlock:
>>
>> if (NODE_MAPPING(sbi)->a_ops->writepage(page,
>> wbc))
>> unlock_page(page);
>> +else
>> +nwritten++;
>>
>> if (--wbc->nr_to_write == 0)
>> break;
>> @@ -1504,7 +1508,10 @@ continue_unlock:
>> step++;
>> goto next_step;
>> }
>> -return nwritten;
>> +out:
>> +if (nwritten)
>> +f2fs_submit_merged_bio(sbi, NODE, WRITE);
>
> IIRC, we don't need to flush this, since f2fs_submit_merged_bio_cond()
> would
> handle this in f2fs_wait_on_page_writeback().
Yes, it covers all the cases in f2fs private codes, but there are still
some
codes in mm or fs directory, and they didn't use
f2fs_wait_on_page_writeback
when waiting page writeback. Such as do_writepages && filemap_fdatawait in
__writeback_single_inode...
>>>
>>> The do_writepages() is okay, which will call f2fs_write_node_pages().
>>> The __writeback_single_inode() won't do filemap_fdatawait() with
>>> WB_SYNC_ALL.
>>> We don't need to take care of truncation as well.
>>>
>>> Any missing one?
>>
>> Another is: while testing with first version of checkpoint error injection, I
>> encounter below dump stack:
>>
>> "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
>> mount D 8801c1bf7960 0 97685 97397 0x0008
>> 8801c1bf7960 8801c1bf7930 88017590 8801c1bf7980
>> 8801c1bf8000 7fff 88021f7be340
>> 817c8880 8801c1bf7978 817c80a5 880214f58fc0
>> Call Trace:
>> [] ? bit_wait+0x50/0x50
>> [] schedule+0x35/0x80
>> [] schedule_timeout+0x292/0x3d0
>> [] ? xen_clocksource_get_cycles+0x15/0x20
>> [] ? ktime_get+0x3c/0xb0
>> [] ? bit_wait+0x50/0x50
>> [] io_schedule_timeout+0xa6/0x110
>> [] bit_wait_io+0x1b/0x60
>> [] __wait_on_bit+0x64/0x90
>> [] wait_on_page_bit+0xc4/0xd0
>> [] ? autoremove_wake_function+0x40/0x40
>> [] truncate_inode_pages_range+0x409/0x840
>> [] ? pcpu_free_area+0x13d/0x1a0
>> [] ? wake_up_bit+0x25/0x30
>> [] truncate_inode_pages_final+0x4c/0x60
>> [] f2fs_evict_inode+0x48/0x390 [f2fs]
>> [] evict+0xc7/0x1a0
>> [] iput+0x197/0x200
>> [] f2fs_fill_super+0xab2/0x1130 [f2fs]
>> [] mount_bdev+0x184/0x1c0
>> [] ? f2fs_commit_super+0x100/0x100 [f2fs]
>> [] f2fs_mount+0x15/0x20 [f2fs]
>> [] mount_fs+0x39/0x160
>> [] vfs_kern_mount+0x67/0x110
>> [] do_mount+0x1bb/0xc80
>> [] SyS_mount+0x83/0xd0
>> [] do_syscall_64+0x6e/0x170
>> [] entry_SYSCALL64_slow_path+0x25/0x25
>>
>> Any thoughts?
>
> I think this should not happen normally, since f2fs_stop_checkpoint() calls
> f2fs_flush_merged_bios().
In write_end_io, f2fs_stop_checkpoint will not call f2fs_flush_merged_bios.
One other problem here is it can cause latency during waiting writeback:
In fsync()
1. fsync_node_pages a/b/c pages is submitted, and d/e/f pages is still in bio
Re: [PATCH 1/2] f2fs: fix to commit bio cache after flushing node pages
On Tue, Sep 27, 2016 at 10:09:03AM +0800, Chao Yu wrote:
> On 2016/9/27 9:39, Jaegeuk Kim wrote:
> > On Tue, Sep 27, 2016 at 08:57:41AM +0800, Chao Yu wrote:
> >> Hi Jaegeuk,
> >>
> >> On 2016/9/27 2:33, Jaegeuk Kim wrote:
> >>> Hi Chao,
> >>>
> >>> On Tue, Sep 27, 2016 at 12:09:52AM +0800, Chao Yu wrote:
> From: Chao Yu
>
> In sync_node_pages, we won't check and commit last merged pages in
> private
> bio cache of f2fs, as these pages were taged as writeback, someone who is
> waiting for writebacking of the page will be blocked until the cache was
> committed by someone else.
>
> We need to commit node type bio cache to avoid potential deadlock or long
> delay of waiting writeback.
>
> Signed-off-by: Chao Yu
> ---
> fs/f2fs/node.c | 11 +--
> 1 file changed, 9 insertions(+), 2 deletions(-)
>
> diff --git a/fs/f2fs/node.c b/fs/f2fs/node.c
> index 9faddcd..f73f774 100644
> --- a/fs/f2fs/node.c
> +++ b/fs/f2fs/node.c
> @@ -1416,6 +1416,7 @@ int sync_node_pages(struct f2fs_sb_info *sbi,
> struct writeback_control *wbc)
> struct pagevec pvec;
> int step = 0;
> int nwritten = 0;
> +int ret = 0;
>
> pagevec_init(&pvec, 0);
>
> @@ -1436,7 +1437,8 @@ next_step:
>
> if (unlikely(f2fs_cp_error(sbi))) {
> pagevec_release(&pvec);
> -return -EIO;
> +ret = -EIO;
> +goto out;
> }
>
> /*
> @@ -1487,6 +1489,8 @@ continue_unlock:
>
> if (NODE_MAPPING(sbi)->a_ops->writepage(page,
> wbc))
> unlock_page(page);
> +else
> +nwritten++;
>
> if (--wbc->nr_to_write == 0)
> break;
> @@ -1504,7 +1508,10 @@ continue_unlock:
> step++;
> goto next_step;
> }
> -return nwritten;
> +out:
> +if (nwritten)
> +f2fs_submit_merged_bio(sbi, NODE, WRITE);
> >>>
> >>> IIRC, we don't need to flush this, since f2fs_submit_merged_bio_cond()
> >>> would
> >>> handle this in f2fs_wait_on_page_writeback().
> >>
> >> Yes, it covers all the cases in f2fs private codes, but there are still
> >> some
> >> codes in mm or fs directory, and they didn't use
> >> f2fs_wait_on_page_writeback
> >> when waiting page writeback. Such as do_writepages && filemap_fdatawait in
> >> __writeback_single_inode...
> >
> > The do_writepages() is okay, which will call f2fs_write_node_pages().
> > The __writeback_single_inode() won't do filemap_fdatawait() with
> > WB_SYNC_ALL.
> > We don't need to take care of truncation as well.
> >
> > Any missing one?
>
> Another is: while testing with first version of checkpoint error injection, I
> encounter below dump stack:
>
> "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
> mount D 8801c1bf7960 0 97685 97397 0x0008
> 8801c1bf7960 8801c1bf7930 88017590 8801c1bf7980
> 8801c1bf8000 7fff 88021f7be340
> 817c8880 8801c1bf7978 817c80a5 880214f58fc0
> Call Trace:
> [] ? bit_wait+0x50/0x50
> [] schedule+0x35/0x80
> [] schedule_timeout+0x292/0x3d0
> [] ? xen_clocksource_get_cycles+0x15/0x20
> [] ? ktime_get+0x3c/0xb0
> [] ? bit_wait+0x50/0x50
> [] io_schedule_timeout+0xa6/0x110
> [] bit_wait_io+0x1b/0x60
> [] __wait_on_bit+0x64/0x90
> [] wait_on_page_bit+0xc4/0xd0
> [] ? autoremove_wake_function+0x40/0x40
> [] truncate_inode_pages_range+0x409/0x840
> [] ? pcpu_free_area+0x13d/0x1a0
> [] ? wake_up_bit+0x25/0x30
> [] truncate_inode_pages_final+0x4c/0x60
> [] f2fs_evict_inode+0x48/0x390 [f2fs]
> [] evict+0xc7/0x1a0
> [] iput+0x197/0x200
> [] f2fs_fill_super+0xab2/0x1130 [f2fs]
> [] mount_bdev+0x184/0x1c0
> [] ? f2fs_commit_super+0x100/0x100 [f2fs]
> [] f2fs_mount+0x15/0x20 [f2fs]
> [] mount_fs+0x39/0x160
> [] vfs_kern_mount+0x67/0x110
> [] do_mount+0x1bb/0xc80
> [] SyS_mount+0x83/0xd0
> [] do_syscall_64+0x6e/0x170
> [] entry_SYSCALL64_slow_path+0x25/0x25
>
> Any thoughts?
I think this should not happen normally, since f2fs_stop_checkpoint() calls
f2fs_flush_merged_bios().
Thanks,
>
> >
> >>
> >> Thanks,
> >>
> >>>
> >>> Thanks,
> >>>
> +return ret;
> }
>
> int wait_on_node_pages_writeback(struct f2fs_sb_info *sbi, nid_t ino)
> --
> 2.7.2
> >>>
> >>> .
> >>>
> >
> > .
> >
Re: [PATCH 1/2] f2fs: fix to commit bio cache after flushing node pages
On 2016/9/27 9:39, Jaegeuk Kim wrote:
> On Tue, Sep 27, 2016 at 08:57:41AM +0800, Chao Yu wrote:
>> Hi Jaegeuk,
>>
>> On 2016/9/27 2:33, Jaegeuk Kim wrote:
>>> Hi Chao,
>>>
>>> On Tue, Sep 27, 2016 at 12:09:52AM +0800, Chao Yu wrote:
From: Chao Yu
In sync_node_pages, we won't check and commit last merged pages in private
bio cache of f2fs, as these pages were taged as writeback, someone who is
waiting for writebacking of the page will be blocked until the cache was
committed by someone else.
We need to commit node type bio cache to avoid potential deadlock or long
delay of waiting writeback.
Signed-off-by: Chao Yu
---
fs/f2fs/node.c | 11 +--
1 file changed, 9 insertions(+), 2 deletions(-)
diff --git a/fs/f2fs/node.c b/fs/f2fs/node.c
index 9faddcd..f73f774 100644
--- a/fs/f2fs/node.c
+++ b/fs/f2fs/node.c
@@ -1416,6 +1416,7 @@ int sync_node_pages(struct f2fs_sb_info *sbi, struct
writeback_control *wbc)
struct pagevec pvec;
int step = 0;
int nwritten = 0;
+ int ret = 0;
pagevec_init(&pvec, 0);
@@ -1436,7 +1437,8 @@ next_step:
if (unlikely(f2fs_cp_error(sbi))) {
pagevec_release(&pvec);
- return -EIO;
+ ret = -EIO;
+ goto out;
}
/*
@@ -1487,6 +1489,8 @@ continue_unlock:
if (NODE_MAPPING(sbi)->a_ops->writepage(page, wbc))
unlock_page(page);
+ else
+ nwritten++;
if (--wbc->nr_to_write == 0)
break;
@@ -1504,7 +1508,10 @@ continue_unlock:
step++;
goto next_step;
}
- return nwritten;
+out:
+ if (nwritten)
+ f2fs_submit_merged_bio(sbi, NODE, WRITE);
>>>
>>> IIRC, we don't need to flush this, since f2fs_submit_merged_bio_cond() would
>>> handle this in f2fs_wait_on_page_writeback().
>>
>> Yes, it covers all the cases in f2fs private codes, but there are still some
>> codes in mm or fs directory, and they didn't use f2fs_wait_on_page_writeback
>> when waiting page writeback. Such as do_writepages && filemap_fdatawait in
>> __writeback_single_inode...
>
> The do_writepages() is okay, which will call f2fs_write_node_pages().
> The __writeback_single_inode() won't do filemap_fdatawait() with WB_SYNC_ALL.
> We don't need to take care of truncation as well.
>
> Any missing one?
Another is: while testing with first version of checkpoint error injection, I
encounter below dump stack:
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
mount D 8801c1bf7960 0 97685 97397 0x0008
8801c1bf7960 8801c1bf7930 88017590 8801c1bf7980
8801c1bf8000 7fff 88021f7be340
817c8880 8801c1bf7978 817c80a5 880214f58fc0
Call Trace:
[] ? bit_wait+0x50/0x50
[] schedule+0x35/0x80
[] schedule_timeout+0x292/0x3d0
[] ? xen_clocksource_get_cycles+0x15/0x20
[] ? ktime_get+0x3c/0xb0
[] ? bit_wait+0x50/0x50
[] io_schedule_timeout+0xa6/0x110
[] bit_wait_io+0x1b/0x60
[] __wait_on_bit+0x64/0x90
[] wait_on_page_bit+0xc4/0xd0
[] ? autoremove_wake_function+0x40/0x40
[] truncate_inode_pages_range+0x409/0x840
[] ? pcpu_free_area+0x13d/0x1a0
[] ? wake_up_bit+0x25/0x30
[] truncate_inode_pages_final+0x4c/0x60
[] f2fs_evict_inode+0x48/0x390 [f2fs]
[] evict+0xc7/0x1a0
[] iput+0x197/0x200
[] f2fs_fill_super+0xab2/0x1130 [f2fs]
[] mount_bdev+0x184/0x1c0
[] ? f2fs_commit_super+0x100/0x100 [f2fs]
[] f2fs_mount+0x15/0x20 [f2fs]
[] mount_fs+0x39/0x160
[] vfs_kern_mount+0x67/0x110
[] do_mount+0x1bb/0xc80
[] SyS_mount+0x83/0xd0
[] do_syscall_64+0x6e/0x170
[] entry_SYSCALL64_slow_path+0x25/0x25
Any thoughts?
>
>>
>> Thanks,
>>
>>>
>>> Thanks,
>>>
+ return ret;
}
int wait_on_node_pages_writeback(struct f2fs_sb_info *sbi, nid_t ino)
--
2.7.2
>>>
>>> .
>>>
>
> .
>
Re: [PATCH 1/2] f2fs: fix to commit bio cache after flushing node pages
On Tue, Sep 27, 2016 at 08:57:41AM +0800, Chao Yu wrote:
> Hi Jaegeuk,
>
> On 2016/9/27 2:33, Jaegeuk Kim wrote:
> > Hi Chao,
> >
> > On Tue, Sep 27, 2016 at 12:09:52AM +0800, Chao Yu wrote:
> >> From: Chao Yu
> >>
> >> In sync_node_pages, we won't check and commit last merged pages in private
> >> bio cache of f2fs, as these pages were taged as writeback, someone who is
> >> waiting for writebacking of the page will be blocked until the cache was
> >> committed by someone else.
> >>
> >> We need to commit node type bio cache to avoid potential deadlock or long
> >> delay of waiting writeback.
> >>
> >> Signed-off-by: Chao Yu
> >> ---
> >> fs/f2fs/node.c | 11 +--
> >> 1 file changed, 9 insertions(+), 2 deletions(-)
> >>
> >> diff --git a/fs/f2fs/node.c b/fs/f2fs/node.c
> >> index 9faddcd..f73f774 100644
> >> --- a/fs/f2fs/node.c
> >> +++ b/fs/f2fs/node.c
> >> @@ -1416,6 +1416,7 @@ int sync_node_pages(struct f2fs_sb_info *sbi, struct
> >> writeback_control *wbc)
> >>struct pagevec pvec;
> >>int step = 0;
> >>int nwritten = 0;
> >> + int ret = 0;
> >>
> >>pagevec_init(&pvec, 0);
> >>
> >> @@ -1436,7 +1437,8 @@ next_step:
> >>
> >>if (unlikely(f2fs_cp_error(sbi))) {
> >>pagevec_release(&pvec);
> >> - return -EIO;
> >> + ret = -EIO;
> >> + goto out;
> >>}
> >>
> >>/*
> >> @@ -1487,6 +1489,8 @@ continue_unlock:
> >>
> >>if (NODE_MAPPING(sbi)->a_ops->writepage(page, wbc))
> >>unlock_page(page);
> >> + else
> >> + nwritten++;
> >>
> >>if (--wbc->nr_to_write == 0)
> >>break;
> >> @@ -1504,7 +1508,10 @@ continue_unlock:
> >>step++;
> >>goto next_step;
> >>}
> >> - return nwritten;
> >> +out:
> >> + if (nwritten)
> >> + f2fs_submit_merged_bio(sbi, NODE, WRITE);
> >
> > IIRC, we don't need to flush this, since f2fs_submit_merged_bio_cond() would
> > handle this in f2fs_wait_on_page_writeback().
>
> Yes, it covers all the cases in f2fs private codes, but there are still some
> codes in mm or fs directory, and they didn't use f2fs_wait_on_page_writeback
> when waiting page writeback. Such as do_writepages && filemap_fdatawait in
> __writeback_single_inode...
The do_writepages() is okay, which will call f2fs_write_node_pages().
The __writeback_single_inode() won't do filemap_fdatawait() with WB_SYNC_ALL.
We don't need to take care of truncation as well.
Any missing one?
>
> Thanks,
>
> >
> > Thanks,
> >
> >> + return ret;
> >> }
> >>
> >> int wait_on_node_pages_writeback(struct f2fs_sb_info *sbi, nid_t ino)
> >> --
> >> 2.7.2
> >
> > .
> >
Re: [PATCH 1/2] f2fs: fix to commit bio cache after flushing node pages
Hi Jaegeuk,
On 2016/9/27 2:33, Jaegeuk Kim wrote:
> Hi Chao,
>
> On Tue, Sep 27, 2016 at 12:09:52AM +0800, Chao Yu wrote:
>> From: Chao Yu
>>
>> In sync_node_pages, we won't check and commit last merged pages in private
>> bio cache of f2fs, as these pages were taged as writeback, someone who is
>> waiting for writebacking of the page will be blocked until the cache was
>> committed by someone else.
>>
>> We need to commit node type bio cache to avoid potential deadlock or long
>> delay of waiting writeback.
>>
>> Signed-off-by: Chao Yu
>> ---
>> fs/f2fs/node.c | 11 +--
>> 1 file changed, 9 insertions(+), 2 deletions(-)
>>
>> diff --git a/fs/f2fs/node.c b/fs/f2fs/node.c
>> index 9faddcd..f73f774 100644
>> --- a/fs/f2fs/node.c
>> +++ b/fs/f2fs/node.c
>> @@ -1416,6 +1416,7 @@ int sync_node_pages(struct f2fs_sb_info *sbi, struct
>> writeback_control *wbc)
>> struct pagevec pvec;
>> int step = 0;
>> int nwritten = 0;
>> +int ret = 0;
>>
>> pagevec_init(&pvec, 0);
>>
>> @@ -1436,7 +1437,8 @@ next_step:
>>
>> if (unlikely(f2fs_cp_error(sbi))) {
>> pagevec_release(&pvec);
>> -return -EIO;
>> +ret = -EIO;
>> +goto out;
>> }
>>
>> /*
>> @@ -1487,6 +1489,8 @@ continue_unlock:
>>
>> if (NODE_MAPPING(sbi)->a_ops->writepage(page, wbc))
>> unlock_page(page);
>> +else
>> +nwritten++;
>>
>> if (--wbc->nr_to_write == 0)
>> break;
>> @@ -1504,7 +1508,10 @@ continue_unlock:
>> step++;
>> goto next_step;
>> }
>> -return nwritten;
>> +out:
>> +if (nwritten)
>> +f2fs_submit_merged_bio(sbi, NODE, WRITE);
>
> IIRC, we don't need to flush this, since f2fs_submit_merged_bio_cond() would
> handle this in f2fs_wait_on_page_writeback().
Yes, it covers all the cases in f2fs private codes, but there are still some
codes in mm or fs directory, and they didn't use f2fs_wait_on_page_writeback
when waiting page writeback. Such as do_writepages && filemap_fdatawait in
__writeback_single_inode...
Thanks,
>
> Thanks,
>
>> +return ret;
>> }
>>
>> int wait_on_node_pages_writeback(struct f2fs_sb_info *sbi, nid_t ino)
>> --
>> 2.7.2
>
> .
>
Re: [PATCH 1/2] f2fs: fix to commit bio cache after flushing node pages
Hi Chao,
On Tue, Sep 27, 2016 at 12:09:52AM +0800, Chao Yu wrote:
> From: Chao Yu
>
> In sync_node_pages, we won't check and commit last merged pages in private
> bio cache of f2fs, as these pages were taged as writeback, someone who is
> waiting for writebacking of the page will be blocked until the cache was
> committed by someone else.
>
> We need to commit node type bio cache to avoid potential deadlock or long
> delay of waiting writeback.
>
> Signed-off-by: Chao Yu
> ---
> fs/f2fs/node.c | 11 +--
> 1 file changed, 9 insertions(+), 2 deletions(-)
>
> diff --git a/fs/f2fs/node.c b/fs/f2fs/node.c
> index 9faddcd..f73f774 100644
> --- a/fs/f2fs/node.c
> +++ b/fs/f2fs/node.c
> @@ -1416,6 +1416,7 @@ int sync_node_pages(struct f2fs_sb_info *sbi, struct
> writeback_control *wbc)
> struct pagevec pvec;
> int step = 0;
> int nwritten = 0;
> + int ret = 0;
>
> pagevec_init(&pvec, 0);
>
> @@ -1436,7 +1437,8 @@ next_step:
>
> if (unlikely(f2fs_cp_error(sbi))) {
> pagevec_release(&pvec);
> - return -EIO;
> + ret = -EIO;
> + goto out;
> }
>
> /*
> @@ -1487,6 +1489,8 @@ continue_unlock:
>
> if (NODE_MAPPING(sbi)->a_ops->writepage(page, wbc))
> unlock_page(page);
> + else
> + nwritten++;
>
> if (--wbc->nr_to_write == 0)
> break;
> @@ -1504,7 +1508,10 @@ continue_unlock:
> step++;
> goto next_step;
> }
> - return nwritten;
> +out:
> + if (nwritten)
> + f2fs_submit_merged_bio(sbi, NODE, WRITE);
IIRC, we don't need to flush this, since f2fs_submit_merged_bio_cond() would
handle this in f2fs_wait_on_page_writeback().
Thanks,
> + return ret;
> }
>
> int wait_on_node_pages_writeback(struct f2fs_sb_info *sbi, nid_t ino)
> --
> 2.7.2
[PATCH 1/2] f2fs: fix to commit bio cache after flushing node pages
From: Chao Yu
In sync_node_pages, we won't check and commit last merged pages in private
bio cache of f2fs, as these pages were taged as writeback, someone who is
waiting for writebacking of the page will be blocked until the cache was
committed by someone else.
We need to commit node type bio cache to avoid potential deadlock or long
delay of waiting writeback.
Signed-off-by: Chao Yu
---
fs/f2fs/node.c | 11 +--
1 file changed, 9 insertions(+), 2 deletions(-)
diff --git a/fs/f2fs/node.c b/fs/f2fs/node.c
index 9faddcd..f73f774 100644
--- a/fs/f2fs/node.c
+++ b/fs/f2fs/node.c
@@ -1416,6 +1416,7 @@ int sync_node_pages(struct f2fs_sb_info *sbi, struct
writeback_control *wbc)
struct pagevec pvec;
int step = 0;
int nwritten = 0;
+ int ret = 0;
pagevec_init(&pvec, 0);
@@ -1436,7 +1437,8 @@ next_step:
if (unlikely(f2fs_cp_error(sbi))) {
pagevec_release(&pvec);
- return -EIO;
+ ret = -EIO;
+ goto out;
}
/*
@@ -1487,6 +1489,8 @@ continue_unlock:
if (NODE_MAPPING(sbi)->a_ops->writepage(page, wbc))
unlock_page(page);
+ else
+ nwritten++;
if (--wbc->nr_to_write == 0)
break;
@@ -1504,7 +1508,10 @@ continue_unlock:
step++;
goto next_step;
}
- return nwritten;
+out:
+ if (nwritten)
+ f2fs_submit_merged_bio(sbi, NODE, WRITE);
+ return ret;
}
int wait_on_node_pages_writeback(struct f2fs_sb_info *sbi, nid_t ino)
--
2.7.2
