[PATCH 1/2] fs: push list presence check into inode_io_list_del()

[PATCH 1/2] fs: push list presence check into inode_io_list_del()

[Mateusz Guzik]

For consistency with sb routines.

Signed-off-by: Mateusz Guzik <mjguzik@gmail.com>
---
 fs/fs-writeback.c | 3 +++
 fs/inode.c        | 4 +---
 2 files changed, 4 insertions(+), 3 deletions(-)

diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c
index f784d8b09b04..5dccbe5fb09d 100644
--- a/fs/fs-writeback.c
+++ b/fs/fs-writeback.c
@@ -1349,6 +1349,9 @@ void inode_io_list_del(struct inode *inode)
 {
 	struct bdi_writeback *wb;
 
+	if (list_empty(&inode->i_io_list))
+		return;
+
 	wb = inode_to_wb_and_lock_list(inode);
 	spin_lock(&inode->i_lock);
 
diff --git a/fs/inode.c b/fs/inode.c
index 3153d725859c..274350095537 100644
--- a/fs/inode.c
+++ b/fs/inode.c
@@ -789,9 +789,7 @@ static void evict(struct inode *inode)
 	BUG_ON(!(inode_state_read_once(inode) & I_FREEING));
 	BUG_ON(!list_empty(&inode->i_lru));
 
-	if (!list_empty(&inode->i_io_list))
-		inode_io_list_del(inode);
-
+	inode_io_list_del(inode);
 	inode_sb_list_del(inode);
 
 	spin_lock(&inode->i_lock);
-- 
2.34.1

[PATCH 2/2] fs: cosmetic fixes to lru handling

[Mateusz Guzik]

1. inode_bit_waitqueue() was somehow placed between __inode_add_lru() and
   inode_add_lru(). move it up
2. assert ->i_lock is held in __inode_add_lru instead of just claiming it is
   needed
3. s/__inode_add_lru/__inode_lru_list_add/ for consistency with itself
   (inode_lru_list_del()) and similar routines for sb and io list
   management
4. push list presence check into inode_lru_list_del(), just like sb and
   io list

Signed-off-by: Mateusz Guzik <mjguzik@gmail.com>
---
 fs/fs-writeback.c  |  2 +-
 fs/inode.c         | 40 +++++++++++++++++++++-------------------
 include/linux/fs.h |  2 +-
 mm/filemap.c       |  4 ++--
 mm/truncate.c      |  6 +++---
 mm/vmscan.c        |  2 +-
 mm/workingset.c    |  2 +-
 7 files changed, 30 insertions(+), 28 deletions(-)

diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c
index 5dccbe5fb09d..c81fffcb3648 100644
--- a/fs/fs-writeback.c
+++ b/fs/fs-writeback.c
@@ -1455,7 +1455,7 @@ static void inode_sync_complete(struct inode *inode)
 
 	inode_state_clear(inode, I_SYNC);
 	/* If inode is clean an unused, put it into LRU now... */
-	inode_add_lru(inode);
+	inode_lru_list_add(inode);
 	/* Called with inode->i_lock which ensures memory ordering. */
 	inode_wake_up_bit(inode, __I_SYNC);
 }
diff --git a/fs/inode.c b/fs/inode.c
index 274350095537..5f18221b5534 100644
--- a/fs/inode.c
+++ b/fs/inode.c
@@ -530,8 +530,21 @@ void ihold(struct inode *inode)
 }
 EXPORT_SYMBOL(ihold);
 
-static void __inode_add_lru(struct inode *inode, bool rotate)
+struct wait_queue_head *inode_bit_waitqueue(struct wait_bit_queue_entry *wqe,
+					    struct inode *inode, u32 bit)
+{
+	void *bit_address;
+
+	bit_address = inode_state_wait_address(inode, bit);
+	init_wait_var_entry(wqe, bit_address, 0);
+	return __var_waitqueue(bit_address);
+}
+EXPORT_SYMBOL(inode_bit_waitqueue);
+
+static void __inode_lru_list_add(struct inode *inode, bool rotate)
 {
+	lockdep_assert_held(&inode->i_lock);
+
 	if (inode_state_read(inode) & (I_DIRTY_ALL | I_SYNC | I_FREEING | I_WILL_FREE))
 		return;
 	if (icount_read(inode))
@@ -547,29 +560,19 @@ static void __inode_add_lru(struct inode *inode, bool rotate)
 		inode_state_set(inode, I_REFERENCED);
 }
 
-struct wait_queue_head *inode_bit_waitqueue(struct wait_bit_queue_entry *wqe,
-					    struct inode *inode, u32 bit)
-{
-	void *bit_address;
-
-	bit_address = inode_state_wait_address(inode, bit);
-	init_wait_var_entry(wqe, bit_address, 0);
-	return __var_waitqueue(bit_address);
-}
-EXPORT_SYMBOL(inode_bit_waitqueue);
-
 /*
  * Add inode to LRU if needed (inode is unused and clean).
- *
- * Needs inode->i_lock held.
  */
-void inode_add_lru(struct inode *inode)
+void inode_lru_list_add(struct inode *inode)
 {
-	__inode_add_lru(inode, false);
+	__inode_lru_list_add(inode, false);
 }
 
 static void inode_lru_list_del(struct inode *inode)
 {
+	if (list_empty(&inode->i_lru))
+		return;
+
 	if (list_lru_del_obj(&inode->i_sb->s_inode_lru, &inode->i_lru))
 		this_cpu_dec(nr_unused);
 }
@@ -1894,7 +1897,7 @@ static void iput_final(struct inode *inode)
 	if (!drop &&
 	    !(inode_state_read(inode) & I_DONTCACHE) &&
 	    (sb->s_flags & SB_ACTIVE)) {
-		__inode_add_lru(inode, true);
+		__inode_lru_list_add(inode, true);
 		spin_unlock(&inode->i_lock);
 		return;
 	}
@@ -1918,8 +1921,7 @@ static void iput_final(struct inode *inode)
 		inode_state_replace(inode, I_WILL_FREE, I_FREEING);
 	}
 
-	if (!list_empty(&inode->i_lru))
-		inode_lru_list_del(inode);
+	inode_lru_list_del(inode);
 	spin_unlock(&inode->i_lock);
 
 	evict(inode);
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 21c73df3ce75..018287664571 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -3510,7 +3510,7 @@ static inline void remove_inode_hash(struct inode *inode)
 }
 
 extern void inode_sb_list_add(struct inode *inode);
-extern void inode_add_lru(struct inode *inode);
+extern void inode_lru_list_add(struct inode *inode);
 
 extern int sb_set_blocksize(struct super_block *, int);
 extern int sb_min_blocksize(struct super_block *, int);
diff --git a/mm/filemap.c b/mm/filemap.c
index 13f0259d993c..add5228a7d97 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -256,7 +256,7 @@ void filemap_remove_folio(struct folio *folio)
 	__filemap_remove_folio(folio, NULL);
 	xa_unlock_irq(&mapping->i_pages);
 	if (mapping_shrinkable(mapping))
-		inode_add_lru(mapping->host);
+		inode_lru_list_add(mapping->host);
 	spin_unlock(&mapping->host->i_lock);
 
 	filemap_free_folio(mapping, folio);
@@ -335,7 +335,7 @@ void delete_from_page_cache_batch(struct address_space *mapping,
 	page_cache_delete_batch(mapping, fbatch);
 	xa_unlock_irq(&mapping->i_pages);
 	if (mapping_shrinkable(mapping))
-		inode_add_lru(mapping->host);
+		inode_lru_list_add(mapping->host);
 	spin_unlock(&mapping->host->i_lock);
 
 	for (i = 0; i < folio_batch_count(fbatch); i++)
diff --git a/mm/truncate.c b/mm/truncate.c
index 91eb92a5ce4f..ad9c0fa29d94 100644
--- a/mm/truncate.c
+++ b/mm/truncate.c
@@ -46,7 +46,7 @@ static void clear_shadow_entries(struct address_space *mapping,
 
 	xas_unlock_irq(&xas);
 	if (mapping_shrinkable(mapping))
-		inode_add_lru(mapping->host);
+		inode_lru_list_add(mapping->host);
 	spin_unlock(&mapping->host->i_lock);
 }
 
@@ -111,7 +111,7 @@ static void truncate_folio_batch_exceptionals(struct address_space *mapping,
 
 	xas_unlock_irq(&xas);
 	if (mapping_shrinkable(mapping))
-		inode_add_lru(mapping->host);
+		inode_lru_list_add(mapping->host);
 	spin_unlock(&mapping->host->i_lock);
 out:
 	folio_batch_remove_exceptionals(fbatch);
@@ -622,7 +622,7 @@ int folio_unmap_invalidate(struct address_space *mapping, struct folio *folio,
 	__filemap_remove_folio(folio, NULL);
 	xa_unlock_irq(&mapping->i_pages);
 	if (mapping_shrinkable(mapping))
-		inode_add_lru(mapping->host);
+		inode_lru_list_add(mapping->host);
 	spin_unlock(&mapping->host->i_lock);
 
 	filemap_free_folio(mapping, folio);
diff --git a/mm/vmscan.c b/mm/vmscan.c
index b2fc8b626d3d..bb4a96c7b682 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -811,7 +811,7 @@ static int __remove_mapping(struct address_space *mapping, struct folio *folio,
 		__filemap_remove_folio(folio, shadow);
 		xa_unlock_irq(&mapping->i_pages);
 		if (mapping_shrinkable(mapping))
-			inode_add_lru(mapping->host);
+			inode_lru_list_add(mapping->host);
 		spin_unlock(&mapping->host->i_lock);
 
 		if (free_folio)
diff --git a/mm/workingset.c b/mm/workingset.c
index 68a76a91111f..d32dc2e02a61 100644
--- a/mm/workingset.c
+++ b/mm/workingset.c
@@ -755,7 +755,7 @@ static enum lru_status shadow_lru_isolate(struct list_head *item,
 	xa_unlock_irq(&mapping->i_pages);
 	if (mapping->host != NULL) {
 		if (mapping_shrinkable(mapping))
-			inode_add_lru(mapping->host);
+			inode_lru_list_add(mapping->host);
 		spin_unlock(&mapping->host->i_lock);
 	}
 	ret = LRU_REMOVED_RETRY;
-- 
2.34.1

Re: [PATCH 1/2] fs: push list presence check into inode_io_list_del()

[Christian Brauner]

On Wed, Oct 22, 2025 at 04:31:11PM +0200, Mateusz Guzik wrote:
> For consistency with sb routines.
> 
> Signed-off-by: Mateusz Guzik <mjguzik@gmail.com>
> ---

Hm, what is this based on? It doesn't apply to vfs-6.19.inode at all.
Could you please resend?

>  fs/fs-writeback.c | 3 +++
>  fs/inode.c        | 4 +---
>  2 files changed, 4 insertions(+), 3 deletions(-)
> 
> diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c
> index f784d8b09b04..5dccbe5fb09d 100644
> --- a/fs/fs-writeback.c
> +++ b/fs/fs-writeback.c
> @@ -1349,6 +1349,9 @@ void inode_io_list_del(struct inode *inode)
>  {
>  	struct bdi_writeback *wb;
>  
> +	if (list_empty(&inode->i_io_list))
> +		return;
> +
>  	wb = inode_to_wb_and_lock_list(inode);
>  	spin_lock(&inode->i_lock);
>  
> diff --git a/fs/inode.c b/fs/inode.c
> index 3153d725859c..274350095537 100644
> --- a/fs/inode.c
> +++ b/fs/inode.c
> @@ -789,9 +789,7 @@ static void evict(struct inode *inode)
>  	BUG_ON(!(inode_state_read_once(inode) & I_FREEING));
>  	BUG_ON(!list_empty(&inode->i_lru));
>  
> -	if (!list_empty(&inode->i_io_list))
> -		inode_io_list_del(inode);
> -
> +	inode_io_list_del(inode);
>  	inode_sb_list_del(inode);
>  
>  	spin_lock(&inode->i_lock);
> -- 
> 2.34.1
>