2022-09-16 03:38:02

by Dan Williams

Subject: [PATCH v2 01/18] fsdax: Wait on @page not @page->_refcount

The __wait_var_event facility calculates a wait queue from a hash of the
address of the variable being passed. Use the @page argument directly as
it is less to type and is the object that is being waited upon.

Cc: Matthew Wilcox <[email protected]>
Cc: Jan Kara <[email protected]>
Cc: "Darrick J. Wong" <[email protected]>
Cc: Jason Gunthorpe <[email protected]>
Cc: Christoph Hellwig <[email protected]>
Cc: John Hubbard <[email protected]>
Signed-off-by: Dan Williams <[email protected]>
---
fs/ext4/inode.c | 8 ++++----
fs/fuse/dax.c | 6 +++---
fs/xfs/xfs_file.c | 6 +++---
mm/memremap.c | 2 +-
4 files changed, 11 insertions(+), 11 deletions(-)

diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index 601214453c3a..b028a4413bea 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -3961,10 +3961,10 @@ int ext4_break_layouts(struct inode *inode)
if (!page)
return 0;

- error = ___wait_var_event(&page->_refcount,
- atomic_read(&page->_refcount) == 1,
- TASK_INTERRUPTIBLE, 0, 0,
- ext4_wait_dax_page(inode));
+ error = ___wait_var_event(page,
+ atomic_read(&page->_refcount) == 1,
+ TASK_INTERRUPTIBLE, 0, 0,
+ ext4_wait_dax_page(inode));
} while (error == 0);

return error;
diff --git a/fs/fuse/dax.c b/fs/fuse/dax.c
index e23e802a8013..4e12108c68af 100644
--- a/fs/fuse/dax.c
+++ b/fs/fuse/dax.c
@@ -676,9 +676,9 @@ static int __fuse_dax_break_layouts(struct inode *inode, bool *retry,
return 0;

*retry = true;
- return ___wait_var_event(&page->_refcount,
- atomic_read(&page->_refcount) == 1, TASK_INTERRUPTIBLE,
- 0, 0, fuse_wait_dax_page(inode));
+ return ___wait_var_event(page, atomic_read(&page->_refcount) == 1,
+ TASK_INTERRUPTIBLE, 0, 0,
+ fuse_wait_dax_page(inode));
}

/* dmap_end == 0 leads to unmapping of whole file */
diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c
index c6c80265c0b2..73e7b7ec0a4c 100644
--- a/fs/xfs/xfs_file.c
+++ b/fs/xfs/xfs_file.c
@@ -827,9 +827,9 @@ xfs_break_dax_layouts(
return 0;

*retry = true;
- return ___wait_var_event(&page->_refcount,
- atomic_read(&page->_refcount) == 1, TASK_INTERRUPTIBLE,
- 0, 0, xfs_wait_dax_page(inode));
+ return ___wait_var_event(page, atomic_read(&page->_refcount) == 1,
+ TASK_INTERRUPTIBLE, 0, 0,
+ xfs_wait_dax_page(inode));
}

int
diff --git a/mm/memremap.c b/mm/memremap.c
index 58b20c3c300b..95f6ffe9cb0f 100644
--- a/mm/memremap.c
+++ b/mm/memremap.c
@@ -520,7 +520,7 @@ bool __put_devmap_managed_page_refs(struct page *page, int refs)
* stable because nobody holds a reference on the page.
*/
if (page_ref_sub_return(page, refs) == 1)
- wake_up_var(&page->_refcount);
+ wake_up_var(page);
return true;
}
EXPORT_SYMBOL(__put_devmap_managed_page_refs);

2022-09-20 14:50:30

by Jason Gunthorpe

Subject: Re: [PATCH v2 01/18] fsdax: Wait on @page not @page->_refcount

On Thu, Sep 15, 2022 at 08:35:15PM -0700, Dan Williams wrote:
> The __wait_var_event facility calculates a wait queue from a hash of the
> address of the variable being passed. Use the @page argument directly as
> it is less to type and is the object that is being waited upon.
>
> Cc: Matthew Wilcox <[email protected]>
> Cc: Jan Kara <[email protected]>
> Cc: "Darrick J. Wong" <[email protected]>
> Cc: Jason Gunthorpe <[email protected]>
> Cc: Christoph Hellwig <[email protected]>
> Cc: John Hubbard <[email protected]>
> Signed-off-by: Dan Williams <[email protected]>
> ---
> fs/ext4/inode.c | 8 ++++----
> fs/fuse/dax.c | 6 +++---
> fs/xfs/xfs_file.c | 6 +++---
> mm/memremap.c | 2 +-
> 4 files changed, 11 insertions(+), 11 deletions(-)

Reviewed-by: Jason Gunthorpe <[email protected]>

Jason