2020-09-04 08:03:33

by Hao Li

[permalink] [raw]
Subject: [PATCH v2] fs: Handle I_DONTCACHE in iput_final() instead of generic_drop_inode()

If generic_drop_inode() returns true, it means iput_final() can evict
this inode regardless of whether it is dirty or not. If we check
I_DONTCACHE in generic_drop_inode(), any inode with this bit set will be
evicted unconditionally. This is not the desired behavior because
I_DONTCACHE only means the inode shouldn't be cached on the LRU list.
As for whether we need to evict this inode, this is what
generic_drop_inode() should do. This patch corrects the usage of
I_DONTCACHE.

This patch was proposed in [1].

[1]: https://lore.kernel.org/linux-fsdevel/[email protected]/

Fixes: dae2f8ed7992 ("fs: Lift XFS_IDONTCACHE to the VFS layer")
Signed-off-by: Hao Li <[email protected]>
---
Changes in v2:
- Adjust code format
- Add Fixes tag in commit message

fs/inode.c | 4 +++-
include/linux/fs.h | 3 +--
2 files changed, 4 insertions(+), 3 deletions(-)

diff --git a/fs/inode.c b/fs/inode.c
index 72c4c347afb7..19ad823f781c 100644
--- a/fs/inode.c
+++ b/fs/inode.c
@@ -1625,7 +1625,9 @@ static void iput_final(struct inode *inode)
else
drop = generic_drop_inode(inode);

- if (!drop && (sb->s_flags & SB_ACTIVE)) {
+ if (!drop &&
+ !(inode->i_state & I_DONTCACHE) &&
+ (sb->s_flags & SB_ACTIVE)) {
inode_add_lru(inode);
spin_unlock(&inode->i_lock);
return;
diff --git a/include/linux/fs.h b/include/linux/fs.h
index e019ea2f1347..93caee80ce47 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -2922,8 +2922,7 @@ extern int inode_needs_sync(struct inode *inode);
extern int generic_delete_inode(struct inode *inode);
static inline int generic_drop_inode(struct inode *inode)
{
- return !inode->i_nlink || inode_unhashed(inode) ||
- (inode->i_state & I_DONTCACHE);
+ return !inode->i_nlink || inode_unhashed(inode);
}
extern void d_mark_dontcache(struct inode *inode);

--
2.28.0




2020-09-06 21:41:11

by Dave Chinner

[permalink] [raw]
Subject: Re: [PATCH v2] fs: Handle I_DONTCACHE in iput_final() instead of generic_drop_inode()

On Fri, Sep 04, 2020 at 03:59:39PM +0800, Hao Li wrote:
> If generic_drop_inode() returns true, it means iput_final() can evict
> this inode regardless of whether it is dirty or not. If we check
> I_DONTCACHE in generic_drop_inode(), any inode with this bit set will be
> evicted unconditionally. This is not the desired behavior because
> I_DONTCACHE only means the inode shouldn't be cached on the LRU list.
> As for whether we need to evict this inode, this is what
> generic_drop_inode() should do. This patch corrects the usage of
> I_DONTCACHE.
>
> This patch was proposed in [1].
>
> [1]: https://lore.kernel.org/linux-fsdevel/[email protected]/
>
> Fixes: dae2f8ed7992 ("fs: Lift XFS_IDONTCACHE to the VFS layer")
> Signed-off-by: Hao Li <[email protected]>
> ---
> Changes in v2:
> - Adjust code format
> - Add Fixes tag in commit message
>
> fs/inode.c | 4 +++-
> include/linux/fs.h | 3 +--
> 2 files changed, 4 insertions(+), 3 deletions(-)

Looks good.

Reviewed-by: Dave Chinner <[email protected]>

--
Dave Chinner
[email protected]

2020-09-08 23:06:40

by Ira Weiny

[permalink] [raw]
Subject: Re: [PATCH v2] fs: Handle I_DONTCACHE in iput_final() instead of generic_drop_inode()

On Fri, Sep 04, 2020 at 03:59:39PM +0800, Hao Li wrote:
> If generic_drop_inode() returns true, it means iput_final() can evict
> this inode regardless of whether it is dirty or not. If we check
> I_DONTCACHE in generic_drop_inode(), any inode with this bit set will be
> evicted unconditionally. This is not the desired behavior because
> I_DONTCACHE only means the inode shouldn't be cached on the LRU list.
> As for whether we need to evict this inode, this is what
> generic_drop_inode() should do. This patch corrects the usage of
> I_DONTCACHE.
>
> This patch was proposed in [1].
>
> [1]: https://lore.kernel.org/linux-fsdevel/[email protected]/
>
> Fixes: dae2f8ed7992 ("fs: Lift XFS_IDONTCACHE to the VFS layer")
> Signed-off-by: Hao Li <[email protected]>

Reviewed-by: Ira Weiny <[email protected]>

> ---
> Changes in v2:
> - Adjust code format
> - Add Fixes tag in commit message
>
> fs/inode.c | 4 +++-
> include/linux/fs.h | 3 +--
> 2 files changed, 4 insertions(+), 3 deletions(-)
>
> diff --git a/fs/inode.c b/fs/inode.c
> index 72c4c347afb7..19ad823f781c 100644
> --- a/fs/inode.c
> +++ b/fs/inode.c
> @@ -1625,7 +1625,9 @@ static void iput_final(struct inode *inode)
> else
> drop = generic_drop_inode(inode);
>
> - if (!drop && (sb->s_flags & SB_ACTIVE)) {
> + if (!drop &&
> + !(inode->i_state & I_DONTCACHE) &&
> + (sb->s_flags & SB_ACTIVE)) {
> inode_add_lru(inode);
> spin_unlock(&inode->i_lock);
> return;
> diff --git a/include/linux/fs.h b/include/linux/fs.h
> index e019ea2f1347..93caee80ce47 100644
> --- a/include/linux/fs.h
> +++ b/include/linux/fs.h
> @@ -2922,8 +2922,7 @@ extern int inode_needs_sync(struct inode *inode);
> extern int generic_delete_inode(struct inode *inode);
> static inline int generic_drop_inode(struct inode *inode)
> {
> - return !inode->i_nlink || inode_unhashed(inode) ||
> - (inode->i_state & I_DONTCACHE);
> + return !inode->i_nlink || inode_unhashed(inode);
> }
> extern void d_mark_dontcache(struct inode *inode);
>
> --
> 2.28.0
>
>
>

2020-09-22 03:10:09

by Hao Li

[permalink] [raw]
Subject: Re: [PATCH v2] fs: Handle I_DONTCACHE in iput_final() instead of generic_drop_inode()

On Mon, Sep 07, 2020 at 07:40:02AM +1000, Dave Chinner wrote:
> On Fri, Sep 04, 2020 at 03:59:39PM +0800, Hao Li wrote:
> > If generic_drop_inode() returns true, it means iput_final() can evict
> > this inode regardless of whether it is dirty or not. If we check
> > I_DONTCACHE in generic_drop_inode(), any inode with this bit set will be
> > evicted unconditionally. This is not the desired behavior because
> > I_DONTCACHE only means the inode shouldn't be cached on the LRU list.
> > As for whether we need to evict this inode, this is what
> > generic_drop_inode() should do. This patch corrects the usage of
> > I_DONTCACHE.
> >
> > This patch was proposed in [1].
> >
> > [1]: https://lore.kernel.org/linux-fsdevel/[email protected]/
> >
> > Fixes: dae2f8ed7992 ("fs: Lift XFS_IDONTCACHE to the VFS layer")
> > Signed-off-by: Hao Li <[email protected]>
> > ---
> > Changes in v2:
> > - Adjust code format
> > - Add Fixes tag in commit message
> >
> > fs/inode.c | 4 +++-
> > include/linux/fs.h | 3 +--
> > 2 files changed, 4 insertions(+), 3 deletions(-)
>
> Looks good.
>
> Reviewed-by: Dave Chinner <[email protected]>
>

Hi,

As discussed in [1], this patch is the basis of another one. Could I
submit the second patch now to change the DCACHE_DONTCACHE behavior or I
have to wait for this patch to be merged.

[1]: https://lkml.org/lkml/2020/8/30/360

Thanks,
Hao Li

> --
> Dave Chinner
> [email protected]
>
>


2020-10-23 14:50:33

by Hao Li

[permalink] [raw]
Subject: Re: [PATCH v2] fs: Handle I_DONTCACHE in iput_final() instead of generic_drop_inode()

Hello,

Ping.

This patch need to be merged... Thanks.

On 2020/9/9 7:03, Ira Weiny wrote:
> On Fri, Sep 04, 2020 at 03:59:39PM +0800, Hao Li wrote:
>> If generic_drop_inode() returns true, it means iput_final() can evict
>> this inode regardless of whether it is dirty or not. If we check
>> I_DONTCACHE in generic_drop_inode(), any inode with this bit set will be
>> evicted unconditionally. This is not the desired behavior because
>> I_DONTCACHE only means the inode shouldn't be cached on the LRU list.
>> As for whether we need to evict this inode, this is what
>> generic_drop_inode() should do. This patch corrects the usage of
>> I_DONTCACHE.
>>
>> This patch was proposed in [1].
>>
>> [1]: https://lore.kernel.org/linux-fsdevel/[email protected]/
>>
>> Fixes: dae2f8ed7992 ("fs: Lift XFS_IDONTCACHE to the VFS layer")
>> Signed-off-by: Hao Li <[email protected]>
> Reviewed-by: Ira Weiny <[email protected]>
>
>> ---
>> Changes in v2:
>> - Adjust code format
>> - Add Fixes tag in commit message
>>
>> fs/inode.c | 4 +++-
>> include/linux/fs.h | 3 +--
>> 2 files changed, 4 insertions(+), 3 deletions(-)
>>
>> diff --git a/fs/inode.c b/fs/inode.c
>> index 72c4c347afb7..19ad823f781c 100644
>> --- a/fs/inode.c
>> +++ b/fs/inode.c
>> @@ -1625,7 +1625,9 @@ static void iput_final(struct inode *inode)
>> else
>> drop = generic_drop_inode(inode);
>>
>> - if (!drop && (sb->s_flags & SB_ACTIVE)) {
>> + if (!drop &&
>> + !(inode->i_state & I_DONTCACHE) &&
>> + (sb->s_flags & SB_ACTIVE)) {
>> inode_add_lru(inode);
>> spin_unlock(&inode->i_lock);
>> return;
>> diff --git a/include/linux/fs.h b/include/linux/fs.h
>> index e019ea2f1347..93caee80ce47 100644
>> --- a/include/linux/fs.h
>> +++ b/include/linux/fs.h
>> @@ -2922,8 +2922,7 @@ extern int inode_needs_sync(struct inode *inode);
>> extern int generic_delete_inode(struct inode *inode);
>> static inline int generic_drop_inode(struct inode *inode)
>> {
>> - return !inode->i_nlink || inode_unhashed(inode) ||
>> - (inode->i_state & I_DONTCACHE);
>> + return !inode->i_nlink || inode_unhashed(inode);
>> }
>> extern void d_mark_dontcache(struct inode *inode);
>>
>> --
>> 2.28.0
>>
>>
>>
>


2020-11-05 10:58:57

by Hao Li

[permalink] [raw]
Subject: Re: [PATCH v2] fs: Handle I_DONTCACHE in iput_final() instead of generic_drop_inode()

Ping :)


On 2020/10/23 15:49, Li, Hao wrote:
> Hello,
>
> Ping.
>
> This patch need to be merged... Thanks.
>
> On 2020/9/9 7:03, Ira Weiny wrote:
>> On Fri, Sep 04, 2020 at 03:59:39PM +0800, Hao Li wrote:
>>> If generic_drop_inode() returns true, it means iput_final() can evict
>>> this inode regardless of whether it is dirty or not. If we check
>>> I_DONTCACHE in generic_drop_inode(), any inode with this bit set will be
>>> evicted unconditionally. This is not the desired behavior because
>>> I_DONTCACHE only means the inode shouldn't be cached on the LRU list.
>>> As for whether we need to evict this inode, this is what
>>> generic_drop_inode() should do. This patch corrects the usage of
>>> I_DONTCACHE.
>>>
>>> This patch was proposed in [1].
>>>
>>> [1]: https://lore.kernel.org/linux-fsdevel/[email protected]/
>>>
>>> Fixes: dae2f8ed7992 ("fs: Lift XFS_IDONTCACHE to the VFS layer")
>>> Signed-off-by: Hao Li <[email protected]>
>> Reviewed-by: Ira Weiny <[email protected]>
>>
>>> ---
>>> Changes in v2:
>>> - Adjust code format
>>> - Add Fixes tag in commit message
>>>
>>> fs/inode.c | 4 +++-
>>> include/linux/fs.h | 3 +--
>>> 2 files changed, 4 insertions(+), 3 deletions(-)
>>>
>>> diff --git a/fs/inode.c b/fs/inode.c
>>> index 72c4c347afb7..19ad823f781c 100644
>>> --- a/fs/inode.c
>>> +++ b/fs/inode.c
>>> @@ -1625,7 +1625,9 @@ static void iput_final(struct inode *inode)
>>> else
>>> drop = generic_drop_inode(inode);
>>>
>>> - if (!drop && (sb->s_flags & SB_ACTIVE)) {
>>> + if (!drop &&
>>> + !(inode->i_state & I_DONTCACHE) &&
>>> + (sb->s_flags & SB_ACTIVE)) {
>>> inode_add_lru(inode);
>>> spin_unlock(&inode->i_lock);
>>> return;
>>> diff --git a/include/linux/fs.h b/include/linux/fs.h
>>> index e019ea2f1347..93caee80ce47 100644
>>> --- a/include/linux/fs.h
>>> +++ b/include/linux/fs.h
>>> @@ -2922,8 +2922,7 @@ extern int inode_needs_sync(struct inode *inode);
>>> extern int generic_delete_inode(struct inode *inode);
>>> static inline int generic_drop_inode(struct inode *inode)
>>> {
>>> - return !inode->i_nlink || inode_unhashed(inode) ||
>>> - (inode->i_state & I_DONTCACHE);
>>> + return !inode->i_nlink || inode_unhashed(inode);
>>> }
>>> extern void d_mark_dontcache(struct inode *inode);
>>>
>>> --
>>> 2.28.0
>>>
>>>
>>>
>