| Message ID | 20200818063056.9094-1-nborisov@suse.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | btrfs: Merge inode_can_compress in inode_need_compress | expand |
On 2020/8/18 下午2:30, Nikolay Borisov wrote: > The latter is the only caller of the former. Just open code can_compress > into need_compress and also remove the warning since it's made redundant > by this change. > > Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: Qu Wenruo <wqu@suse.com> Thanks, Qu > --- > fs/btrfs/inode.c | 21 +++------------------ > 1 file changed, 3 insertions(+), 18 deletions(-) > > diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c > index 15dc8b6871ac..19e1918bad5c 100644 > --- a/fs/btrfs/inode.c > +++ b/fs/btrfs/inode.c > @@ -410,17 +410,6 @@ static noinline int add_async_extent(struct async_chunk *cow, > return 0; > } > > -/* > - * Check if the inode has flags compatible with compression > - */ > -static inline bool inode_can_compress(struct btrfs_inode *inode) > -{ > - if (inode->flags & BTRFS_INODE_NODATACOW || > - inode->flags & BTRFS_INODE_NODATASUM) > - return false; > - return true; > -} > - > /* > * Check if the inode needs to be submitted to compression, based on mount > * options, defragmentation, properties or heuristics. > @@ -430,12 +419,9 @@ static inline int inode_need_compress(struct btrfs_inode *inode, u64 start, > { > struct btrfs_fs_info *fs_info = inode->root->fs_info; > > - if (!inode_can_compress(inode)) { > - WARN(IS_ENABLED(CONFIG_BTRFS_DEBUG), > - KERN_ERR "BTRFS: unexpected compression for ino %llu\n", > - btrfs_ino(inode)); > + if (inode->flags & BTRFS_INODE_NODATACOW || > + inode->flags & BTRFS_INODE_NODATASUM) > return 0; > - } > /* force compress */ > if (btrfs_test_opt(fs_info, FORCE_COMPRESS)) > return 1; > @@ -1833,8 +1819,7 @@ int btrfs_run_delalloc_range(struct btrfs_inode *inode, struct page *locked_page > } else if (inode->flags & BTRFS_INODE_PREALLOC && !force_cow) { > ret = run_delalloc_nocow(inode, locked_page, start, end, > page_started, 0, nr_written); > - } else if (!inode_can_compress(inode) || > - !inode_need_compress(inode, start, end)) { > + } else if (!inode_need_compress(inode, start, end)) { > ret = cow_file_range(inode, locked_page, start, end, > page_started, nr_written, 1); > } else { >
On Tue, Aug 18, 2020 at 09:30:56AM +0300, Nikolay Borisov wrote: > The latter is the only caller of the former. Just open code can_compress > into need_compress and also remove the warning since it's made redundant > by this change. We had discussions and some disagreements in the past regarding the need/can compression helpers (v1) https://lore.kernel.org/linux-btrfs/20180515073622.18732-1-wqu@suse.com/ (v2) https://lore.kernel.org/linux-btrfs/20190701051225.17957-1-wqu@suse.com/ The fix got merged as there was a pending user report and bug to fix, but I remember there's more to do. While this patch cleans up some of the code, I don't think it's going the right way, we have 2 semantics for the compression decision and the helpers codify that. I haven't read the discussions yet again and will have to do that before merging this patch.
On Tue, Aug 18, 2020 at 09:30:56AM +0300, Nikolay Borisov wrote: > The latter is the only caller of the former. Just open code can_compress > into need_compress and also remove the warning since it's made redundant > by this change. > > Signed-off-by: Nikolay Borisov <nborisov@suse.com> > --- > fs/btrfs/inode.c | 21 +++------------------ > 1 file changed, 3 insertions(+), 18 deletions(-) > > diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c > index 15dc8b6871ac..19e1918bad5c 100644 > --- a/fs/btrfs/inode.c > +++ b/fs/btrfs/inode.c > @@ -410,17 +410,6 @@ static noinline int add_async_extent(struct async_chunk *cow, > return 0; > } > > -/* > - * Check if the inode has flags compatible with compression > - */ > -static inline bool inode_can_compress(struct btrfs_inode *inode) > -{ > - if (inode->flags & BTRFS_INODE_NODATACOW || > - inode->flags & BTRFS_INODE_NODATASUM) > - return false; > - return true; > -} > - > /* > * Check if the inode needs to be submitted to compression, based on mount > * options, defragmentation, properties or heuristics. > @@ -430,12 +419,9 @@ static inline int inode_need_compress(struct btrfs_inode *inode, u64 start, > { > struct btrfs_fs_info *fs_info = inode->root->fs_info; > > - if (!inode_can_compress(inode)) { > - WARN(IS_ENABLED(CONFIG_BTRFS_DEBUG), > - KERN_ERR "BTRFS: unexpected compression for ino %llu\n", > - btrfs_ino(inode)); > + if (inode->flags & BTRFS_INODE_NODATACOW || > + inode->flags & BTRFS_INODE_NODATASUM) > return 0; This serves as a runtime friendly assert, when inode_need_compress is called from compress_file_range. First call in btrfs_run_delalloc_range duplicates the nodatacow/nodatasum which would be cleaned up by this patch but we'd lose the warning in case compress_file_range detects the unexpected flags.
On 31.08.20 г. 23:40 ч., David Sterba wrote: > On Tue, Aug 18, 2020 at 09:30:56AM +0300, Nikolay Borisov wrote: >> The latter is the only caller of the former. Just open code can_compress >> into need_compress and also remove the warning since it's made redundant >> by this change. >> >> Signed-off-by: Nikolay Borisov <nborisov@suse.com> >> --- >> fs/btrfs/inode.c | 21 +++------------------ >> 1 file changed, 3 insertions(+), 18 deletions(-) >> >> diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c >> index 15dc8b6871ac..19e1918bad5c 100644 >> --- a/fs/btrfs/inode.c >> +++ b/fs/btrfs/inode.c >> @@ -410,17 +410,6 @@ static noinline int add_async_extent(struct async_chunk *cow, >> return 0; >> } >> >> -/* >> - * Check if the inode has flags compatible with compression >> - */ >> -static inline bool inode_can_compress(struct btrfs_inode *inode) >> -{ >> - if (inode->flags & BTRFS_INODE_NODATACOW || >> - inode->flags & BTRFS_INODE_NODATASUM) >> - return false; >> - return true; >> -} >> - >> /* >> * Check if the inode needs to be submitted to compression, based on mount >> * options, defragmentation, properties or heuristics. >> @@ -430,12 +419,9 @@ static inline int inode_need_compress(struct btrfs_inode *inode, u64 start, >> { >> struct btrfs_fs_info *fs_info = inode->root->fs_info; >> >> - if (!inode_can_compress(inode)) { >> - WARN(IS_ENABLED(CONFIG_BTRFS_DEBUG), >> - KERN_ERR "BTRFS: unexpected compression for ino %llu\n", >> - btrfs_ino(inode)); >> + if (inode->flags & BTRFS_INODE_NODATACOW || >> + inode->flags & BTRFS_INODE_NODATASUM) >> return 0; > > This serves as a runtime friendly assert, when inode_need_compress is > called from compress_file_range. > > First call in btrfs_run_delalloc_range duplicates the > nodatacow/nodatasum which would be cleaned up by this patch but we'd > lose the warning in case compress_file_range detects the unexpected > flags. > I think we should simply come to an agreement at which stage of a write shall we check for the presence of flags. IMO the less places we have the better. This will obviate the need for a run-time assert... Frankly I think we should be checking only at the time of btrfs_run_delalloc_range
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index 15dc8b6871ac..19e1918bad5c 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -410,17 +410,6 @@ static noinline int add_async_extent(struct async_chunk *cow, return 0; } -/* - * Check if the inode has flags compatible with compression - */ -static inline bool inode_can_compress(struct btrfs_inode *inode) -{ - if (inode->flags & BTRFS_INODE_NODATACOW || - inode->flags & BTRFS_INODE_NODATASUM) - return false; - return true; -} - /* * Check if the inode needs to be submitted to compression, based on mount * options, defragmentation, properties or heuristics. @@ -430,12 +419,9 @@ static inline int inode_need_compress(struct btrfs_inode *inode, u64 start, { struct btrfs_fs_info *fs_info = inode->root->fs_info; - if (!inode_can_compress(inode)) { - WARN(IS_ENABLED(CONFIG_BTRFS_DEBUG), - KERN_ERR "BTRFS: unexpected compression for ino %llu\n", - btrfs_ino(inode)); + if (inode->flags & BTRFS_INODE_NODATACOW || + inode->flags & BTRFS_INODE_NODATASUM) return 0; - } /* force compress */ if (btrfs_test_opt(fs_info, FORCE_COMPRESS)) return 1; @@ -1833,8 +1819,7 @@ int btrfs_run_delalloc_range(struct btrfs_inode *inode, struct page *locked_page } else if (inode->flags & BTRFS_INODE_PREALLOC && !force_cow) { ret = run_delalloc_nocow(inode, locked_page, start, end, page_started, 0, nr_written); - } else if (!inode_can_compress(inode) || - !inode_need_compress(inode, start, end)) { + } else if (!inode_need_compress(inode, start, end)) { ret = cow_file_range(inode, locked_page, start, end, page_started, nr_written, 1); } else {
The latter is the only caller of the former. Just open code can_compress into need_compress and also remove the warning since it's made redundant by this change. Signed-off-by: Nikolay Borisov <nborisov@suse.com> --- fs/btrfs/inode.c | 21 +++------------------ 1 file changed, 3 insertions(+), 18 deletions(-)