On 07/29, Chao Yu wrote:
> On 2019/7/29 13:57, Jaegeuk Kim wrote:
> > On 07/23, Chao Yu wrote:
> >> On 2019/7/23 10:36, Jaegeuk Kim wrote:
> >>> On 07/19, Chao Yu wrote:
> >>>> Pinning a file is heavy, because skipping pinned files make GC
> >>>> running with heavy load or no effect.
> >>>
> >>> Pinned file is a part of NOCOW files, so I don't think we can simply drop
> >>> it
> >>> for backward compatibility.
> >>
> >> Yes,
> >>
> >> But what I concerned is that pin file is too heavy, so in order to satisfy
> >> below
> >> demand, how about introducing pin_file_2 flag to triggering IPU only during
> >> flush/writeback.
> >
> > That can be done by cold files?
>
> Then it may inherit property of cold type file, e.g. a) goes into cold area;
> b)
> update with very low frequency.
>
> Actually pin_file_2 could be used by db-wal/log file, which are updated
> frequently, and should go to hot/warm area, it does not match above two
> property.
How about considering another name like "IPU-only mode"?
fallocate write Flag GC
Pin_file: preallocate IPU FS_NOCOW_FL Not allowed
IPU_file: Not preallocate IPU N/A Default by temperature
Cold_file: Not preallocate IPU N/A Move in cold area
Hot_file: Not preallocate IPU/OPU N/A Move in hot area
>
> Thank,
>
> >
> >>
> >>>
> >>>>
> >>>> So that this patch propose to separate nocow and pinfile semantics:
> >>>> - NOCoW flag can only be set on regular file.
> >>>> - NOCoW file will only trigger IPU at common writeback/flush.
> >>>> - NOCow file will do OPU during GC.
> >>>>
> >>>> For the demand of 1) avoid fragment of file's physical block and
> >>>> 2) userspace don't care about file's specific physical address,
> >>>> tagging file as NOCoW will be cheaper than pinned one.
> >>
> >> ^^^
> >>
> >> Thanks,
> >>
> >>>>
> >>>> Signed-off-by: Chao Yu <yuch...@huawei.com>
> >>>> ---
> >>>> v2:
> >>>> - rebase code to fix compile error.
> >>>> fs/f2fs/data.c | 3 ++-
> >>>> fs/f2fs/f2fs.h | 1 +
> >>>> fs/f2fs/file.c | 22 +++++++++++++++++++---
> >>>> 3 files changed, 22 insertions(+), 4 deletions(-)
> >>>>
> >>>> diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
> >>>> index a2a28bb269bf..15fb8954c363 100644
> >>>> --- a/fs/f2fs/data.c
> >>>> +++ b/fs/f2fs/data.c
> >>>> @@ -1884,7 +1884,8 @@ static inline bool
> >>>> check_inplace_update_policy(struct inode *inode,
> >>>>
> >>>> bool f2fs_should_update_inplace(struct inode *inode, struct
> >>>> f2fs_io_info *fio)
> >>>> {
> >>>> - if (f2fs_is_pinned_file(inode))
> >>>> + if (f2fs_is_pinned_file(inode) ||
> >>>> + F2FS_I(inode)->i_flags & F2FS_NOCOW_FL)
> >>>> return true;
> >>>>
> >>>> /* if this is cold file, we should overwrite to avoid
> >>>> fragmentation */
> >>>> diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
> >>>> index 596ab3e1dd7b..f6c5a3d2e659 100644
> >>>> --- a/fs/f2fs/f2fs.h
> >>>> +++ b/fs/f2fs/f2fs.h
> >>>> @@ -2374,6 +2374,7 @@ static inline void f2fs_change_bit(unsigned int
> >>>> nr, char *addr)
> >>>> #define F2FS_NOATIME_FL 0x00000080 /* do not update
> >>>> atime */
> >>>> #define F2FS_INDEX_FL 0x00001000 /* hash-indexed
> >>>> directory */
> >>>> #define F2FS_DIRSYNC_FL 0x00010000 /* dirsync behaviour
> >>>> (directories only) */
> >>>> +#define F2FS_NOCOW_FL 0x00800000 /* Do not cow file */
> >>>> #define F2FS_PROJINHERIT_FL 0x20000000 /* Create with
> >>>> parents projid */
> >>>>
> >>>> /* Flags that should be inherited by new inodes from their parent. */
> >>>> diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
> >>>> index 7ca545874060..ae0fec54cac6 100644
> >>>> --- a/fs/f2fs/file.c
> >>>> +++ b/fs/f2fs/file.c
> >>>> @@ -1692,6 +1692,7 @@ static const struct {
> >>>> { F2FS_NOATIME_FL, FS_NOATIME_FL },
> >>>> { F2FS_INDEX_FL, FS_INDEX_FL },
> >>>> { F2FS_DIRSYNC_FL, FS_DIRSYNC_FL },
> >>>> + { F2FS_NOCOW_FL, FS_NOCOW_FL },
> >>>> { F2FS_PROJINHERIT_FL, FS_PROJINHERIT_FL },
> >>>> };
> >>>>
> >>>> @@ -1715,7 +1716,8 @@ static const struct {
> >>>> FS_NODUMP_FL | \
> >>>> FS_NOATIME_FL | \
> >>>> FS_DIRSYNC_FL | \
> >>>> - FS_PROJINHERIT_FL)
> >>>> + FS_PROJINHERIT_FL | \
> >>>> + FS_NOCOW_FL)
> >>>>
> >>>> /* Convert f2fs on-disk i_flags to FS_IOC_{GET,SET}FLAGS flags */
> >>>> static inline u32 f2fs_iflags_to_fsflags(u32 iflags)
> >>>> @@ -1753,8 +1755,6 @@ static int f2fs_ioc_getflags(struct file *filp,
> >>>> unsigned long arg)
> >>>> fsflags |= FS_ENCRYPT_FL;
> >>>> if (f2fs_has_inline_data(inode) ||
> >>>> f2fs_has_inline_dentry(inode))
> >>>> fsflags |= FS_INLINE_DATA_FL;
> >>>> - if (is_inode_flag_set(inode, FI_PIN_FILE))
> >>>> - fsflags |= FS_NOCOW_FL;
> >>>>
> >>>> fsflags &= F2FS_GETTABLE_FS_FL;
> >>>>
> >>>> @@ -1794,6 +1794,22 @@ static int f2fs_ioc_setflags(struct file *filp,
> >>>> unsigned long arg)
> >>>> if (ret)
> >>>> goto out;
> >>>>
> >>>> + if ((fsflags ^ old_fsflags) & FS_NOCOW_FL) {
> >>>> + if (!S_ISREG(inode->i_mode)) {
> >>>> + ret = -EINVAL;
> >>>> + goto out;
> >>>> + }
> >>>> +
> >>>> + if (f2fs_should_update_outplace(inode, NULL)) {
> >>>> + ret = -EINVAL;
> >>>> + goto out;
> >>>> + }
> >>>> +
> >>>> + ret = f2fs_convert_inline_inode(inode);
> >>>> + if (ret)
> >>>> + goto out;
> >>>> + }
> >>>> +
> >>>> ret = f2fs_setflags_common(inode, iflags,
> >>>> f2fs_fsflags_to_iflags(F2FS_SETTABLE_FS_FL));
> >>>> out:
> >>>> --
> >>>> 2.18.0.rc1
> >>> .
> >>>
> > .
> >
