| Message ID | 20250410014945.2140781-7-mcgrof@kernel.org (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | mm: enhance migration work around on noref buffer-heads | expand |
On Wed 09-04-25 18:49:43, Luis Chamberlain wrote: > From: Davidlohr Bueso <dave@stgolabs.net> > > Trivially introduce the wrapper and enable ext4_free_blocks() to use > it, which has a cond_resched to begin with. Convert to the new nonatomic > flavor to benefit from potential performance benefits and adapt in the > future vs migration such that semantics are kept. > > Suggested-by: Jan Kara <jack@suse.cz> > Signed-off-by: Davidlohr Bueso <dave@stgolabs.net> > Signed-off-by: Luis Chamberlain <mcgrof@kernel.org> > --- > fs/ext4/inode.c | 2 ++ > fs/ext4/mballoc.c | 3 ++- > include/linux/buffer_head.h | 6 ++++++ > 3 files changed, 10 insertions(+), 1 deletion(-) > > diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c > index 1dc09ed5d403..b7acb5d3adcb 100644 > --- a/fs/ext4/inode.c > +++ b/fs/ext4/inode.c > @@ -860,6 +860,8 @@ struct buffer_head *ext4_getblk(handle_t *handle, struct inode *inode, > return sb_find_get_block(inode->i_sb, map.m_pblk); > > /* > + * Potential TODO: use sb_find_get_block_nonatomic() instead. > + * Yes, please. Since we are behind nowait check, we are fine with blocking... Honza > * Since bh could introduce extra ref count such as referred by > * journal_head etc. Try to avoid using __GFP_MOVABLE here > * as it may fail the migration when journal_head remains. > diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c > index 0d523e9fb3d5..6f4265b21e19 100644 > --- a/fs/ext4/mballoc.c > +++ b/fs/ext4/mballoc.c > @@ -6644,7 +6644,8 @@ void ext4_free_blocks(handle_t *handle, struct inode *inode, > for (i = 0; i < count; i++) { > cond_resched(); > if (is_metadata) > - bh = sb_find_get_block(inode->i_sb, block + i); > + bh = sb_find_get_block_nonatomic(inode->i_sb, > + block + i); > ext4_forget(handle, is_metadata, inode, bh, block + i); > } > } > diff --git a/include/linux/buffer_head.h b/include/linux/buffer_head.h > index 2b5458517def..8db10ca288fc 100644 > --- a/include/linux/buffer_head.h > +++ b/include/linux/buffer_head.h > @@ -399,6 +399,12 @@ sb_find_get_block(struct super_block *sb, sector_t block) > return __find_get_block(sb->s_bdev, block, sb->s_blocksize); > } > > +static inline struct buffer_head * > +sb_find_get_block_nonatomic(struct super_block *sb, sector_t block) > +{ > + return __find_get_block_nonatomic(sb->s_bdev, block, sb->s_blocksize); > +} > + This hunk probably belongs to some introductory patch implementing nonatomic helpers. Honza
On Thu, 10 Apr 2025, Jan Kara wrote: >> @@ -860,6 +860,8 @@ struct buffer_head *ext4_getblk(handle_t *handle, struct inode *inode, >> return sb_find_get_block(inode->i_sb, map.m_pblk); >> >> /* >> + * Potential TODO: use sb_find_get_block_nonatomic() instead. >> + * > >Yes, please. Since we are behind nowait check, we are fine with blocking... Yes, I will send a follow up that replaces that getblk_unmovable() with sb_find_get_block_nonatomic().
diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c index 1dc09ed5d403..b7acb5d3adcb 100644 --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -860,6 +860,8 @@ struct buffer_head *ext4_getblk(handle_t *handle, struct inode *inode, return sb_find_get_block(inode->i_sb, map.m_pblk); /* + * Potential TODO: use sb_find_get_block_nonatomic() instead. + * * Since bh could introduce extra ref count such as referred by * journal_head etc. Try to avoid using __GFP_MOVABLE here * as it may fail the migration when journal_head remains. diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c index 0d523e9fb3d5..6f4265b21e19 100644 --- a/fs/ext4/mballoc.c +++ b/fs/ext4/mballoc.c @@ -6644,7 +6644,8 @@ void ext4_free_blocks(handle_t *handle, struct inode *inode, for (i = 0; i < count; i++) { cond_resched(); if (is_metadata) - bh = sb_find_get_block(inode->i_sb, block + i); + bh = sb_find_get_block_nonatomic(inode->i_sb, + block + i); ext4_forget(handle, is_metadata, inode, bh, block + i); } } diff --git a/include/linux/buffer_head.h b/include/linux/buffer_head.h index 2b5458517def..8db10ca288fc 100644 --- a/include/linux/buffer_head.h +++ b/include/linux/buffer_head.h @@ -399,6 +399,12 @@ sb_find_get_block(struct super_block *sb, sector_t block) return __find_get_block(sb->s_bdev, block, sb->s_blocksize); } +static inline struct buffer_head * +sb_find_get_block_nonatomic(struct super_block *sb, sector_t block) +{ + return __find_get_block_nonatomic(sb->s_bdev, block, sb->s_blocksize); +} + static inline void map_bh(struct buffer_head *bh, struct super_block *sb, sector_t block) {