Re: [PATCH v4 03/23] mm/gup: move try_get_compound_head() to top, fix minor issues

2019-11-13 Thread Ira Weiny 
On Tue, Nov 12, 2019 at 08:26:50PM -0800, John Hubbard wrote:
> An upcoming patch uses try_get_compound_head() more widely,
> so move it to the top of gup.c.
> 
> Also fix a tiny spelling error and a checkpatch.pl warning.
> 
> Signed-off-by: John Hubbard 

Simple enough...

Reviewed-by: Ira Weiny 

> ---
>  mm/gup.c | 29 +++--
>  1 file changed, 15 insertions(+), 14 deletions(-)
> 
> diff --git a/mm/gup.c b/mm/gup.c
> index 199da99e8ffc..933524de6249 100644
> --- a/mm/gup.c
> +++ b/mm/gup.c
> @@ -29,6 +29,21 @@ struct follow_page_context {
>   unsigned int page_mask;
>  };
>  
> +/*
> + * Return the compound head page with ref appropriately incremented,
> + * or NULL if that failed.
> + */
> +static inline struct page *try_get_compound_head(struct page *page, int refs)
> +{
> + struct page *head = compound_head(page);
> +
> + if (WARN_ON_ONCE(page_ref_count(head) < 0))
> + return NULL;
> + if (unlikely(!page_cache_add_speculative(head, refs)))
> + return NULL;
> + return head;
> +}
> +
>  /**
>   * put_user_pages_dirty_lock() - release and optionally dirty gup-pinned 
> pages
>   * @pages:  array of pages to be maybe marked dirty, and definitely released.
> @@ -1793,20 +1808,6 @@ static void __maybe_unused undo_dev_pagemap(int *nr, 
> int nr_start,
>   }
>  }
>  
> -/*
> - * Return the compund head page with ref appropriately incremented,
> - * or NULL if that failed.
> - */
> -static inline struct page *try_get_compound_head(struct page *page, int refs)
> -{
> - struct page *head = compound_head(page);
> - if (WARN_ON_ONCE(page_ref_count(head) < 0))
> - return NULL;
> - if (unlikely(!page_cache_add_speculative(head, refs)))
> - return NULL;
> - return head;
> -}
> -
>  #ifdef CONFIG_ARCH_HAS_PTE_SPECIAL
>  static int gup_pte_range(pmd_t pmd, unsigned long addr, unsigned long end,
>unsigned int flags, struct page **pages, int *nr)
> -- 
> 2.24.0
>

Re: [PATCH v4 03/23] mm/gup: move try_get_compound_head() to top, fix minor issues

2019-11-13 Thread Jan Kara 
On Tue 12-11-19 20:26:50, John Hubbard wrote:
> An upcoming patch uses try_get_compound_head() more widely,
> so move it to the top of gup.c.
> 
> Also fix a tiny spelling error and a checkpatch.pl warning.
> 
> Signed-off-by: John Hubbard 

Looks good. You can add:

Reviewed-by: Jan Kara 

Honza

> ---
>  mm/gup.c | 29 +++--
>  1 file changed, 15 insertions(+), 14 deletions(-)
> 
> diff --git a/mm/gup.c b/mm/gup.c
> index 199da99e8ffc..933524de6249 100644
> --- a/mm/gup.c
> +++ b/mm/gup.c
> @@ -29,6 +29,21 @@ struct follow_page_context {
>   unsigned int page_mask;
>  };
>  
> +/*
> + * Return the compound head page with ref appropriately incremented,
> + * or NULL if that failed.
> + */
> +static inline struct page *try_get_compound_head(struct page *page, int refs)
> +{
> + struct page *head = compound_head(page);
> +
> + if (WARN_ON_ONCE(page_ref_count(head) < 0))
> + return NULL;
> + if (unlikely(!page_cache_add_speculative(head, refs)))
> + return NULL;
> + return head;
> +}
> +
>  /**
>   * put_user_pages_dirty_lock() - release and optionally dirty gup-pinned 
> pages
>   * @pages:  array of pages to be maybe marked dirty, and definitely released.
> @@ -1793,20 +1808,6 @@ static void __maybe_unused undo_dev_pagemap(int *nr, 
> int nr_start,
>   }
>  }
>  
> -/*
> - * Return the compund head page with ref appropriately incremented,
> - * or NULL if that failed.
> - */
> -static inline struct page *try_get_compound_head(struct page *page, int refs)
> -{
> - struct page *head = compound_head(page);
> - if (WARN_ON_ONCE(page_ref_count(head) < 0))
> - return NULL;
> - if (unlikely(!page_cache_add_speculative(head, refs)))
> - return NULL;
> - return head;
> -}
> -
>  #ifdef CONFIG_ARCH_HAS_PTE_SPECIAL
>  static int gup_pte_range(pmd_t pmd, unsigned long addr, unsigned long end,
>unsigned int flags, struct page **pages, int *nr)
> -- 
> 2.24.0
> 
-- 
Jan Kara 
SUSE Labs, CR

[PATCH v4 03/23] mm/gup: move try_get_compound_head() to top, fix minor issues

2019-11-12 Thread John Hubbard 
An upcoming patch uses try_get_compound_head() more widely,
so move it to the top of gup.c.

Also fix a tiny spelling error and a checkpatch.pl warning.

Signed-off-by: John Hubbard 
---
 mm/gup.c | 29 +++--
 1 file changed, 15 insertions(+), 14 deletions(-)

diff --git a/mm/gup.c b/mm/gup.c
index 199da99e8ffc..933524de6249 100644
--- a/mm/gup.c
+++ b/mm/gup.c
@@ -29,6 +29,21 @@ struct follow_page_context {
unsigned int page_mask;
 };
 
+/*
+ * Return the compound head page with ref appropriately incremented,
+ * or NULL if that failed.
+ */
+static inline struct page *try_get_compound_head(struct page *page, int refs)
+{
+   struct page *head = compound_head(page);
+
+   if (WARN_ON_ONCE(page_ref_count(head) < 0))
+   return NULL;
+   if (unlikely(!page_cache_add_speculative(head, refs)))
+   return NULL;
+   return head;
+}
+
 /**
  * put_user_pages_dirty_lock() - release and optionally dirty gup-pinned pages
  * @pages:  array of pages to be maybe marked dirty, and definitely released.
@@ -1793,20 +1808,6 @@ static void __maybe_unused undo_dev_pagemap(int *nr, int 
nr_start,
}
 }
 
-/*
- * Return the compund head page with ref appropriately incremented,
- * or NULL if that failed.
- */
-static inline struct page *try_get_compound_head(struct page *page, int refs)
-{
-   struct page *head = compound_head(page);
-   if (WARN_ON_ONCE(page_ref_count(head) < 0))
-   return NULL;
-   if (unlikely(!page_cache_add_speculative(head, refs)))
-   return NULL;
-   return head;
-}
-
 #ifdef CONFIG_ARCH_HAS_PTE_SPECIAL
 static int gup_pte_range(pmd_t pmd, unsigned long addr, unsigned long end,
 unsigned int flags, struct page **pages, int *nr)
-- 
2.24.0