2013-04-22 08:25:03

by Joonsoo Kim

Subject: [PATCH] mm, highmem: remove useless virtual variable in page_address_map

We can get virtual address without virtual field.
So remove it.

Signed-off-by: Joonsoo Kim <[email protected]>

diff --git a/mm/highmem.c b/mm/highmem.c
index b32b70c..8f4c250 100644
--- a/mm/highmem.c
+++ b/mm/highmem.c
@@ -320,7 +320,6 @@ EXPORT_SYMBOL(kunmap_high);
*/
struct page_address_map {
struct page *page;
- void *virtual;
struct list_head list;
};

@@ -362,7 +361,10 @@ void *page_address(const struct page *page)

list_for_each_entry(pam, &pas->lh, list) {
if (pam->page == page) {
- ret = pam->virtual;
+ int nr;
+
+ nr = pam - page_address_map;
+ ret = PKMAP_ADDR(nr);
goto done;
}
}
@@ -391,7 +393,6 @@ void set_page_address(struct page *page, void *virtual)
if (virtual) { /* Add */
pam = &page_address_maps[PKMAP_NR((unsigned long)virtual)];
pam->page = page;
- pam->virtual = virtual;

spin_lock_irqsave(&pas->lock, flags);
list_add_tail(&pam->list, &pas->lh);
--
1.7.9.5

2013-04-25 22:01:00

by Andrew Morton

Subject: Re: [PATCH] mm, highmem: remove useless virtual variable in page_address_map

On Mon, 22 Apr 2013 17:26:28 +0900 Joonsoo Kim <[email protected]> wrote:

> We can get virtual address without virtual field.
> So remove it.
>
> ...
>
> --- a/mm/highmem.c
> +++ b/mm/highmem.c
> @@ -320,7 +320,6 @@ EXPORT_SYMBOL(kunmap_high);
> */
> struct page_address_map {
> struct page *page;
> - void *virtual;
> struct list_head list;
> };
>
> @@ -362,7 +361,10 @@ void *page_address(const struct page *page)
>
> list_for_each_entry(pam, &pas->lh, list) {
> if (pam->page == page) {
> - ret = pam->virtual;
> + int nr;
> +
> + nr = pam - page_address_map;

Doesn't compile. Presumably you meant page_address_maps.

I'll drop this - please resend if/when it has been runtime tested.

2013-04-26 00:21:10

by Joonsoo Kim

Subject: Re: [PATCH] mm, highmem: remove useless virtual variable in page_address_map

On Thu, Apr 25, 2013 at 03:00:57PM -0700, Andrew Morton wrote:
> On Mon, 22 Apr 2013 17:26:28 +0900 Joonsoo Kim <[email protected]> wrote:
>
> > We can get virtual address without virtual field.
> > So remove it.
> >
> > ...
> >
> > --- a/mm/highmem.c
> > +++ b/mm/highmem.c
> > @@ -320,7 +320,6 @@ EXPORT_SYMBOL(kunmap_high);
> > */
> > struct page_address_map {
> > struct page *page;
> > - void *virtual;
> > struct list_head list;
> > };
> >
> > @@ -362,7 +361,10 @@ void *page_address(const struct page *page)
> >
> > list_for_each_entry(pam, &pas->lh, list) {
> > if (pam->page == page) {
> > - ret = pam->virtual;
> > + int nr;
> > +
> > + nr = pam - page_address_map;
>
> Doesn't compile. Presumably you meant page_address_maps.
>
> I'll drop this - please resend if/when it has been runtime tested.

Sorry for that.
I'll resend when it has been runtime tested.

Thanks.

>
>
> --
> To unsubscribe, send a message with 'unsubscribe linux-mm' in
> the body to [email protected]. For more info on Linux MM,
> see: http://www.linux-mm.org/ .
> Don't email: <a href=mailto:"[email protected]"> [email protected] </a>