2014-04-18 13:10:17

by Jianyu Zhan

[permalink] [raw]
Subject: [PATCH] mm/swap: cleanup *lru_cache_add* functions

In mm/swap.c, __lru_cache_add() is exported, but actually there are
no users outside this file. However, lru_cache_add() is supposed to
be used by vfs, or whatever others, but it is not exported.

This patch exports lru_cache_add(), and makes __lru_cache_add()
static. It also exports lru_cache_add_file() and
lru_cache_add_anon(), which both delegate to __lru_cache_add().

Signed-off-by: Jianyu Zhan <[email protected]>
---
include/linux/swap.h | 19 ++-----------------
mm/swap.c | 33 +++++++++++++++++++++++++--------
2 files changed, 27 insertions(+), 25 deletions(-)

diff --git a/include/linux/swap.h b/include/linux/swap.h
index 3507115..5a14b92 100644
--- a/include/linux/swap.h
+++ b/include/linux/swap.h
@@ -308,8 +308,9 @@ extern unsigned long nr_free_pagecache_pages(void);


/* linux/mm/swap.c */
-extern void __lru_cache_add(struct page *);
extern void lru_cache_add(struct page *);
+extern void lru_cache_add_anon(struct page *page);
+extern void lru_cache_add_file(struct page *page);
extern void lru_add_page_tail(struct page *page, struct page *page_tail,
struct lruvec *lruvec, struct list_head *head);
extern void activate_page(struct page *);
@@ -323,22 +324,6 @@ extern void swap_setup(void);

extern void add_page_to_unevictable_list(struct page *page);

-/**
- * lru_cache_add: add a page to the page lists
- * @page: the page to add
- */
-static inline void lru_cache_add_anon(struct page *page)
-{
- ClearPageActive(page);
- __lru_cache_add(page);
-}
-
-static inline void lru_cache_add_file(struct page *page)
-{
- ClearPageActive(page);
- __lru_cache_add(page);
-}
-
/* linux/mm/vmscan.c */
extern unsigned long try_to_free_pages(struct zonelist *zonelist, int order,
gfp_t gfp_mask, nodemask_t *mask);
diff --git a/mm/swap.c b/mm/swap.c
index 9ce43ba..0c79363 100644
--- a/mm/swap.c
+++ b/mm/swap.c
@@ -582,13 +582,7 @@ void mark_page_accessed(struct page *page)
}
EXPORT_SYMBOL(mark_page_accessed);

-/*
- * Queue the page for addition to the LRU via pagevec. The decision on whether
- * to add the page to the [in]active [file|anon] list is deferred until the
- * pagevec is drained. This gives a chance for the caller of __lru_cache_add()
- * have the page added to the active list using mark_page_accessed().
- */
-void __lru_cache_add(struct page *page)
+static void __lru_cache_add(struct page *page)
{
struct pagevec *pvec = &get_cpu_var(lru_add_pvec);

@@ -598,11 +592,33 @@ void __lru_cache_add(struct page *page)
pagevec_add(pvec, page);
put_cpu_var(lru_add_pvec);
}
-EXPORT_SYMBOL(__lru_cache_add);
+
+/**
+ * lru_cache_add: add a page to the page lists
+ * @page: the page to add
+ */
+void lru_cache_add_anon(struct page *page)
+{
+ ClearPageActive(page);
+ __lru_cache_add(page);
+}
+EXPORT_SYMBOL(lru_cache_add_anon);
+
+void lru_cache_add_file(struct page *page)
+{
+ ClearPageActive(page);
+ __lru_cache_add(page);
+}
+EXPORT_SYMBOL(lru_cache_add_file);

/**
* lru_cache_add - add a page to a page list
* @page: the page to be added to the LRU.
+ *
+ * Queue the page for addition to the LRU via pagevec. The decision on whether
+ * to add the page to the [in]active [file|anon] list is deferred until the
+ * pagevec is drained. This gives a chance for the caller of lru_cache_add()
+ * have the page added to the active list using mark_page_accessed().
*/
void lru_cache_add(struct page *page)
{
@@ -610,6 +626,7 @@ void lru_cache_add(struct page *page)
VM_BUG_ON_PAGE(PageLRU(page), page);
__lru_cache_add(page);
}
+EXPORT_SYMBOL(lru_cache_add);

/**
* add_page_to_unevictable_list - add a page to the unevictable list
--
1.9.0.GIT


2014-04-18 13:51:28

by Christoph Hellwig

[permalink] [raw]
Subject: Re: [PATCH] mm/swap: cleanup *lru_cache_add* functions

On Fri, Apr 18, 2014 at 09:09:51PM +0800, Jianyu Zhan wrote:
> In mm/swap.c, __lru_cache_add() is exported, but actually there are
> no users outside this file. However, lru_cache_add() is supposed to
> be used by vfs, or whatever others, but it is not exported.

There are no modular users of lru_cache_add, so please don't needlessly
export it.

2014-04-18 15:39:42

by Jianyu Zhan

[permalink] [raw]
Subject: Re: [PATCH] mm/swap: cleanup *lru_cache_add* functions

Hi, Christoph Hellwig,

>There are no modular users of lru_cache_add, so please don't needlessly
>export it.

yep, I re-checked and found there is no module user of neither
lru_cache_add() nor lru_cache_add_anon(), so don't export it.

Here is the renewed patch:
---

In mm/swap.c, __lru_cache_add() is exported, but actually there are
no users outside this file. However, lru_cache_add() is supposed to
be used by vfs, or whatever others, but it is not exported.

This patch unexports __lru_cache_add(), and makes it static.
It also exports lru_cache_add_file(), as it is use by cifs, which
be loaded as module.

Signed-off-by: Jianyu Zhan <[email protected]>
---
include/linux/swap.h | 19 ++-----------------
mm/swap.c | 31 +++++++++++++++++++++++--------
2 files changed, 25 insertions(+), 25 deletions(-)

diff --git a/include/linux/swap.h b/include/linux/swap.h
index 3507115..5a14b92 100644
--- a/include/linux/swap.h
+++ b/include/linux/swap.h
@@ -308,8 +308,9 @@ extern unsigned long nr_free_pagecache_pages(void);


/* linux/mm/swap.c */
-extern void __lru_cache_add(struct page *);
extern void lru_cache_add(struct page *);
+extern void lru_cache_add_anon(struct page *page);
+extern void lru_cache_add_file(struct page *page);
extern void lru_add_page_tail(struct page *page, struct page *page_tail,
struct lruvec *lruvec, struct list_head *head);
extern void activate_page(struct page *);
@@ -323,22 +324,6 @@ extern void swap_setup(void);

extern void add_page_to_unevictable_list(struct page *page);

-/**
- * lru_cache_add: add a page to the page lists
- * @page: the page to add
- */
-static inline void lru_cache_add_anon(struct page *page)
-{
- ClearPageActive(page);
- __lru_cache_add(page);
-}
-
-static inline void lru_cache_add_file(struct page *page)
-{
- ClearPageActive(page);
- __lru_cache_add(page);
-}
-
/* linux/mm/vmscan.c */
extern unsigned long try_to_free_pages(struct zonelist *zonelist, int order,
gfp_t gfp_mask, nodemask_t *mask);
diff --git a/mm/swap.c b/mm/swap.c
index ab3f508..c0cd7d0 100644
--- a/mm/swap.c
+++ b/mm/swap.c
@@ -582,13 +582,7 @@ void mark_page_accessed(struct page *page)
}
EXPORT_SYMBOL(mark_page_accessed);

-/*
- * Queue the page for addition to the LRU via pagevec. The decision on whether
- * to add the page to the [in]active [file|anon] list is deferred until the
- * pagevec is drained. This gives a chance for the caller of __lru_cache_add()
- * have the page added to the active list using mark_page_accessed().
- */
-void __lru_cache_add(struct page *page)
+static void __lru_cache_add(struct page *page)
{
struct pagevec *pvec = &get_cpu_var(lru_add_pvec);

@@ -598,11 +592,32 @@ void __lru_cache_add(struct page *page)
pagevec_add(pvec, page);
put_cpu_var(lru_add_pvec);
}
-EXPORT_SYMBOL(__lru_cache_add);
+
+/**
+ * lru_cache_add: add a page to the page lists
+ * @page: the page to add
+ */
+void lru_cache_add_anon(struct page *page)
+{
+ ClearPageActive(page);
+ __lru_cache_add(page);
+}
+
+void lru_cache_add_file(struct page *page)
+{
+ ClearPageActive(page);
+ __lru_cache_add(page);
+}
+EXPORT_SYMBOL(lru_cache_add_file);

/**
* lru_cache_add - add a page to a page list
* @page: the page to be added to the LRU.
+ *
+ * Queue the page for addition to the LRU via pagevec. The decision on whether
+ * to add the page to the [in]active [file|anon] list is deferred until the
+ * pagevec is drained. This gives a chance for the caller of lru_cache_add()
+ * have the page added to the active list using mark_page_accessed().
*/
void lru_cache_add(struct page *page)
{
--
1.9.0.GIT

2014-04-18 21:14:42

by Rik van Riel

[permalink] [raw]
Subject: Re: [PATCH] mm/swap: cleanup *lru_cache_add* functions

On 04/18/2014 11:39 AM, Jianyu Zhan wrote:
> Hi, Christoph Hellwig,
>
>> There are no modular users of lru_cache_add, so please don't needlessly
>> export it.
>
> yep, I re-checked and found there is no module user of neither
> lru_cache_add() nor lru_cache_add_anon(), so don't export it.
>
> Here is the renewed patch:
> ---
>
> In mm/swap.c, __lru_cache_add() is exported, but actually there are
> no users outside this file. However, lru_cache_add() is supposed to
> be used by vfs, or whatever others, but it is not exported.
>
> This patch unexports __lru_cache_add(), and makes it static.
> It also exports lru_cache_add_file(), as it is use by cifs, which
> be loaded as module.
>
> Signed-off-by: Jianyu Zhan <[email protected]>

Acked-by: Rik van Riel <[email protected]>


--
All rights reversed

2014-04-21 01:01:55

by Zhang Yanfei

[permalink] [raw]
Subject: Re: [PATCH] mm/swap: cleanup *lru_cache_add* functions

Hi Jianyu

On 04/18/2014 11:39 PM, Jianyu Zhan wrote:
> Hi, Christoph Hellwig,
>
>> There are no modular users of lru_cache_add, so please don't needlessly
>> export it.
>
> yep, I re-checked and found there is no module user of neither
> lru_cache_add() nor lru_cache_add_anon(), so don't export it.
>
> Here is the renewed patch:
> ---
>
> In mm/swap.c, __lru_cache_add() is exported, but actually there are
> no users outside this file. However, lru_cache_add() is supposed to
> be used by vfs, or whatever others, but it is not exported.
>
> This patch unexports __lru_cache_add(), and makes it static.
> It also exports lru_cache_add_file(), as it is use by cifs, which
> be loaded as module.

What should be exported?

lru_cache_add()
lru_cache_add_anon()
lru_cache_add_file()

It seems you only export lru_cache_add_file() in the patch.

Thanks

>
> Signed-off-by: Jianyu Zhan <[email protected]>
> ---
> include/linux/swap.h | 19 ++-----------------
> mm/swap.c | 31 +++++++++++++++++++++++--------
> 2 files changed, 25 insertions(+), 25 deletions(-)
>
> diff --git a/include/linux/swap.h b/include/linux/swap.h
> index 3507115..5a14b92 100644
> --- a/include/linux/swap.h
> +++ b/include/linux/swap.h
> @@ -308,8 +308,9 @@ extern unsigned long nr_free_pagecache_pages(void);
>
>
> /* linux/mm/swap.c */
> -extern void __lru_cache_add(struct page *);
> extern void lru_cache_add(struct page *);
> +extern void lru_cache_add_anon(struct page *page);
> +extern void lru_cache_add_file(struct page *page);
> extern void lru_add_page_tail(struct page *page, struct page *page_tail,
> struct lruvec *lruvec, struct list_head *head);
> extern void activate_page(struct page *);
> @@ -323,22 +324,6 @@ extern void swap_setup(void);
>
> extern void add_page_to_unevictable_list(struct page *page);
>
> -/**
> - * lru_cache_add: add a page to the page lists
> - * @page: the page to add
> - */
> -static inline void lru_cache_add_anon(struct page *page)
> -{
> - ClearPageActive(page);
> - __lru_cache_add(page);
> -}
> -
> -static inline void lru_cache_add_file(struct page *page)
> -{
> - ClearPageActive(page);
> - __lru_cache_add(page);
> -}
> -
> /* linux/mm/vmscan.c */
> extern unsigned long try_to_free_pages(struct zonelist *zonelist, int order,
> gfp_t gfp_mask, nodemask_t *mask);
> diff --git a/mm/swap.c b/mm/swap.c
> index ab3f508..c0cd7d0 100644
> --- a/mm/swap.c
> +++ b/mm/swap.c
> @@ -582,13 +582,7 @@ void mark_page_accessed(struct page *page)
> }
> EXPORT_SYMBOL(mark_page_accessed);
>
> -/*
> - * Queue the page for addition to the LRU via pagevec. The decision on whether
> - * to add the page to the [in]active [file|anon] list is deferred until the
> - * pagevec is drained. This gives a chance for the caller of __lru_cache_add()
> - * have the page added to the active list using mark_page_accessed().
> - */
> -void __lru_cache_add(struct page *page)
> +static void __lru_cache_add(struct page *page)
> {
> struct pagevec *pvec = &get_cpu_var(lru_add_pvec);
>
> @@ -598,11 +592,32 @@ void __lru_cache_add(struct page *page)
> pagevec_add(pvec, page);
> put_cpu_var(lru_add_pvec);
> }
> -EXPORT_SYMBOL(__lru_cache_add);
> +
> +/**
> + * lru_cache_add: add a page to the page lists
> + * @page: the page to add
> + */
> +void lru_cache_add_anon(struct page *page)
> +{
> + ClearPageActive(page);
> + __lru_cache_add(page);
> +}
> +
> +void lru_cache_add_file(struct page *page)
> +{
> + ClearPageActive(page);
> + __lru_cache_add(page);
> +}
> +EXPORT_SYMBOL(lru_cache_add_file);
>
> /**
> * lru_cache_add - add a page to a page list
> * @page: the page to be added to the LRU.
> + *
> + * Queue the page for addition to the LRU via pagevec. The decision on whether
> + * to add the page to the [in]active [file|anon] list is deferred until the
> + * pagevec is drained. This gives a chance for the caller of lru_cache_add()
> + * have the page added to the active list using mark_page_accessed().
> */
> void lru_cache_add(struct page *page)
> {
>


--
Thanks.
Zhang Yanfei

2014-04-21 04:03:24

by Jianyu Zhan

[permalink] [raw]
Subject: Re: [PATCH] mm/swap: cleanup *lru_cache_add* functions

Hi, Yanfei,

On Mon, Apr 21, 2014 at 9:00 AM, Zhang Yanfei
<[email protected]> wrote:
> What should be exported?
>
> lru_cache_add()
> lru_cache_add_anon()
> lru_cache_add_file()
>
> It seems you only export lru_cache_add_file() in the patch.

Right, lru_cache_add_anon() is only used by VM code, so it should not
be exported.

lru_cache_add_file() and lru_cache_add() are supposed to be used by
vfs ans fs code.

But now only lru_cache_add_file() is used by CIFS and FUSE, which
both could be
built as module, so it must be exported; and lru_cache_add() has now
no module users,
so as Rik suggests, it is unexported too.


Thanks,
Jianyu Zhan

2014-04-21 06:11:19

by Zhang Yanfei

[permalink] [raw]
Subject: Re: [PATCH] mm/swap: cleanup *lru_cache_add* functions

On 04/21/2014 12:02 PM, Jianyu Zhan wrote:
> Hi, Yanfei,
>
> On Mon, Apr 21, 2014 at 9:00 AM, Zhang Yanfei
> <[email protected]> wrote:
>> What should be exported?
>>
>> lru_cache_add()
>> lru_cache_add_anon()
>> lru_cache_add_file()
>>
>> It seems you only export lru_cache_add_file() in the patch.
>
> Right, lru_cache_add_anon() is only used by VM code, so it should not
> be exported.
>
> lru_cache_add_file() and lru_cache_add() are supposed to be used by
> vfs ans fs code.
>
> But now only lru_cache_add_file() is used by CIFS and FUSE, which
> both could be
> built as module, so it must be exported; and lru_cache_add() has now
> no module users,
> so as Rik suggests, it is unexported too.
>

OK. So The sentence in the patch log confused me:

[ However, lru_cache_add() is supposed to
be used by vfs, or whatever others, but it is not exported.]

otherwise,
Reviewed-by: Zhang Yanfei <[email protected]>

Thanks.

--
Thanks.
Zhang Yanfei