From 1d39834fba99c48edd3d4887ccd474da61a1ada7 Mon Sep 17 00:00:00 2001 From: Nikolay Borisov Date: Thu, 22 Mar 2018 11:52:10 -0400 Subject: [PATCH] ext4: remove EXT4_STATE_DIOREAD_LOCK flag Commit 16c54688592c ("ext4: Allow parallel DIO reads") reworked the way locking happens around parallel dio reads. This resulted in obviating the need for EXT4_STATE_DIOREAD_LOCK flag and accompanying logic. Currently this amounts to dead code so let's remove it. No functional changes Signed-off-by: Nikolay Borisov Signed-off-by: Theodore Ts'o Reviewed-by: Jan Kara --- fs/ext4/ext4.h | 17 ----------------- fs/ext4/extents.c | 19 +++++-------------- fs/ext4/inode.c | 8 -------- fs/ext4/ioctl.c | 4 ---- fs/ext4/move_extent.c | 4 ---- fs/ext4/super.c | 12 +++++------- 6 files changed, 10 insertions(+), 54 deletions(-) diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h index 3241475a1733..a42e71203e53 100644 --- a/fs/ext4/ext4.h +++ b/fs/ext4/ext4.h @@ -1522,8 +1522,6 @@ enum { EXT4_STATE_EXT_MIGRATE, /* Inode is migrating */ EXT4_STATE_DIO_UNWRITTEN, /* need convert on dio done*/ EXT4_STATE_NEWENTRY, /* File just added to dir */ - EXT4_STATE_DIOREAD_LOCK, /* Disable support for dio read - nolocking */ EXT4_STATE_MAY_INLINE_DATA, /* may have in-inode data */ EXT4_STATE_EXT_PRECACHED, /* extents have been precached */ EXT4_STATE_LUSTRE_EA_INODE, /* Lustre-style ea_inode */ @@ -3181,21 +3179,6 @@ static inline void set_bitmap_uptodate(struct buffer_head *bh) set_bit(BH_BITMAP_UPTODATE, &(bh)->b_state); } -/* - * Disable DIO read nolock optimization, so new dioreaders will be forced - * to grab i_mutex - */ -static inline void ext4_inode_block_unlocked_dio(struct inode *inode) -{ - ext4_set_inode_state(inode, EXT4_STATE_DIOREAD_LOCK); - smp_mb(); -} -static inline void ext4_inode_resume_unlocked_dio(struct inode *inode) -{ - smp_mb(); - ext4_clear_inode_state(inode, EXT4_STATE_DIOREAD_LOCK); -} - #define in_range(b, first, len) ((b) >= (first) && (b) <= (first) + (len) - 1) /* For ioend & aio unwritten conversion wait queues */ diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c index 054416e9d827..837f0a6357c7 100644 --- a/fs/ext4/extents.c +++ b/fs/ext4/extents.c @@ -4796,7 +4796,6 @@ static long ext4_zero_range(struct file *file, loff_t offset, flags |= EXT4_GET_BLOCKS_KEEP_SIZE; /* Wait all existing dio workers, newcomers will block on i_mutex */ - ext4_inode_block_unlocked_dio(inode); inode_dio_wait(inode); /* Preallocate the range including the unaligned edges */ @@ -4807,7 +4806,7 @@ static long ext4_zero_range(struct file *file, loff_t offset, round_down(offset, 1 << blkbits)) >> blkbits, new_size, flags); if (ret) - goto out_dio; + goto out_mutex; } @@ -4824,7 +4823,7 @@ static long ext4_zero_range(struct file *file, loff_t offset, ret = ext4_update_disksize_before_punch(inode, offset, len); if (ret) { up_write(&EXT4_I(inode)->i_mmap_sem); - goto out_dio; + goto out_mutex; } /* Now release the pages and zero block aligned part of pages */ truncate_pagecache_range(inode, start, end - 1); @@ -4834,10 +4833,10 @@ static long ext4_zero_range(struct file *file, loff_t offset, flags); up_write(&EXT4_I(inode)->i_mmap_sem); if (ret) - goto out_dio; + goto out_mutex; } if (!partial_begin && !partial_end) - goto out_dio; + goto out_mutex; /* * In worst case we have to writeout two nonadjacent unwritten @@ -4850,7 +4849,7 @@ static long ext4_zero_range(struct file *file, loff_t offset, if (IS_ERR(handle)) { ret = PTR_ERR(handle); ext4_std_error(inode->i_sb, ret); - goto out_dio; + goto out_mutex; } inode->i_mtime = inode->i_ctime = current_time(inode); @@ -4875,8 +4874,6 @@ static long ext4_zero_range(struct file *file, loff_t offset, ext4_handle_sync(handle); ext4_journal_stop(handle); -out_dio: - ext4_inode_resume_unlocked_dio(inode); out_mutex: inode_unlock(inode); return ret; @@ -4964,11 +4961,9 @@ long ext4_fallocate(struct file *file, int mode, loff_t offset, loff_t len) } /* Wait all existing dio workers, newcomers will block on i_mutex */ - ext4_inode_block_unlocked_dio(inode); inode_dio_wait(inode); ret = ext4_alloc_file_blocks(file, lblk, max_blocks, new_size, flags); - ext4_inode_resume_unlocked_dio(inode); if (ret) goto out; @@ -5485,7 +5480,6 @@ int ext4_collapse_range(struct inode *inode, loff_t offset, loff_t len) } /* Wait for existing dio to complete */ - ext4_inode_block_unlocked_dio(inode); inode_dio_wait(inode); /* @@ -5562,7 +5556,6 @@ int ext4_collapse_range(struct inode *inode, loff_t offset, loff_t len) ext4_journal_stop(handle); out_mmap: up_write(&EXT4_I(inode)->i_mmap_sem); - ext4_inode_resume_unlocked_dio(inode); out_mutex: inode_unlock(inode); return ret; @@ -5635,7 +5628,6 @@ int ext4_insert_range(struct inode *inode, loff_t offset, loff_t len) } /* Wait for existing dio to complete */ - ext4_inode_block_unlocked_dio(inode); inode_dio_wait(inode); /* @@ -5737,7 +5729,6 @@ int ext4_insert_range(struct inode *inode, loff_t offset, loff_t len) ext4_journal_stop(handle); out_mmap: up_write(&EXT4_I(inode)->i_mmap_sem); - ext4_inode_resume_unlocked_dio(inode); out_mutex: inode_unlock(inode); return ret; diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c index d8a692f04156..951a3d69ed17 100644 --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -4252,7 +4252,6 @@ int ext4_punch_hole(struct inode *inode, loff_t offset, loff_t length) } /* Wait all existing dio workers, newcomers will block on i_mutex */ - ext4_inode_block_unlocked_dio(inode); inode_dio_wait(inode); /* @@ -4325,7 +4324,6 @@ int ext4_punch_hole(struct inode *inode, loff_t offset, loff_t length) ext4_journal_stop(handle); out_dio: up_write(&EXT4_I(inode)->i_mmap_sem); - ext4_inode_resume_unlocked_dio(inode); out_mutex: inode_unlock(inode); return ret; @@ -5507,9 +5505,7 @@ int ext4_setattr(struct dentry *dentry, struct iattr *attr) */ if (orphan) { if (!ext4_should_journal_data(inode)) { - ext4_inode_block_unlocked_dio(inode); inode_dio_wait(inode); - ext4_inode_resume_unlocked_dio(inode); } else ext4_wait_for_tail_page_commit(inode); } @@ -6000,7 +5996,6 @@ int ext4_change_inode_journal_flag(struct inode *inode, int val) return -EROFS; /* Wait for all existing dio workers */ - ext4_inode_block_unlocked_dio(inode); inode_dio_wait(inode); /* @@ -6016,7 +6011,6 @@ int ext4_change_inode_journal_flag(struct inode *inode, int val) err = filemap_write_and_wait(inode->i_mapping); if (err < 0) { up_write(&EXT4_I(inode)->i_mmap_sem); - ext4_inode_resume_unlocked_dio(inode); return err; } } @@ -6039,7 +6033,6 @@ int ext4_change_inode_journal_flag(struct inode *inode, int val) if (err < 0) { jbd2_journal_unlock_updates(journal); percpu_up_write(&sbi->s_journal_flag_rwsem); - ext4_inode_resume_unlocked_dio(inode); return err; } ext4_clear_inode_flag(inode, EXT4_INODE_JOURNAL_DATA); @@ -6051,7 +6044,6 @@ int ext4_change_inode_journal_flag(struct inode *inode, int val) if (val) up_write(&EXT4_I(inode)->i_mmap_sem); - ext4_inode_resume_unlocked_dio(inode); /* Finally we can mark the inode as dirty. */ diff --git a/fs/ext4/ioctl.c b/fs/ext4/ioctl.c index 9ac33a7cbd32..a7074115d6f6 100644 --- a/fs/ext4/ioctl.c +++ b/fs/ext4/ioctl.c @@ -124,8 +124,6 @@ static long swap_inode_boot_loader(struct super_block *sb, truncate_inode_pages(&inode_bl->i_data, 0); /* Wait for all existing dio workers */ - ext4_inode_block_unlocked_dio(inode); - ext4_inode_block_unlocked_dio(inode_bl); inode_dio_wait(inode); inode_dio_wait(inode_bl); @@ -186,8 +184,6 @@ static long swap_inode_boot_loader(struct super_block *sb, ext4_double_up_write_data_sem(inode, inode_bl); journal_err_out: - ext4_inode_resume_unlocked_dio(inode); - ext4_inode_resume_unlocked_dio(inode_bl); unlock_two_nondirectories(inode, inode_bl); iput(inode_bl); return err; diff --git a/fs/ext4/move_extent.c b/fs/ext4/move_extent.c index b96e4bd3b3ec..8e17efdcbf11 100644 --- a/fs/ext4/move_extent.c +++ b/fs/ext4/move_extent.c @@ -601,8 +601,6 @@ ext4_move_extents(struct file *o_filp, struct file *d_filp, __u64 orig_blk, lock_two_nondirectories(orig_inode, donor_inode); /* Wait for all existing dio workers */ - ext4_inode_block_unlocked_dio(orig_inode); - ext4_inode_block_unlocked_dio(donor_inode); inode_dio_wait(orig_inode); inode_dio_wait(donor_inode); @@ -693,8 +691,6 @@ ext4_move_extents(struct file *o_filp, struct file *d_filp, __u64 orig_blk, ext4_ext_drop_refs(path); kfree(path); ext4_double_up_write_data_sem(orig_inode, donor_inode); - ext4_inode_resume_unlocked_dio(orig_inode); - ext4_inode_resume_unlocked_dio(donor_inode); unlock_two_nondirectories(orig_inode, donor_inode); return ret; diff --git a/fs/ext4/super.c b/fs/ext4/super.c index 756f515b762d..3a13b7b24616 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -101,15 +101,13 @@ static struct inode *ext4_get_journal_inode(struct super_block *sb, * i_data_sem (rw) * * truncate: - * sb_start_write -> i_mutex -> EXT4_STATE_DIOREAD_LOCK (w) -> i_mmap_sem (w) -> - * i_mmap_rwsem (w) -> page lock - * sb_start_write -> i_mutex -> EXT4_STATE_DIOREAD_LOCK (w) -> i_mmap_sem (w) -> - * transaction start -> i_data_sem (rw) + * sb_start_write -> i_mutex -> i_mmap_sem (w) -> i_mmap_rwsem (w) -> page lock + * sb_start_write -> i_mutex -> i_mmap_sem (w) -> transaction start -> + * i_data_sem (rw) * * direct IO: - * sb_start_write -> i_mutex -> EXT4_STATE_DIOREAD_LOCK (r) -> mmap_sem - * sb_start_write -> i_mutex -> EXT4_STATE_DIOREAD_LOCK (r) -> - * transaction start -> i_data_sem (rw) + * sb_start_write -> i_mutex -> mmap_sem + * sb_start_write -> i_mutex -> transaction start -> i_data_sem (rw) * * writepages: * transaction start -> page lock(s) -> i_data_sem (rw) -- GitLab