On 9/3/21 9:35 AM, Linus Torvalds wrote:
On Thu, Sep 2, 2021 at 2:53 PM Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> wrote:
+ int ret = 1;
..
+ ret = 0;
+ break;
..
+ ret = 0;
+ break;
..
+ return ret;
Hmm. I think "ret" is unnecessary, and this could just have been
return addr == end;
at the end to check that we did it all.
No?
Yes, definitely.
So, to be extra clear even though this is tiny and trivial: this incremental
change, on top of the current patch, looks good to me:
diff --git a/mm/gup.c b/mm/gup.c
index 7a406d79bd2e..74142c621556 100644
--- a/mm/gup.c
+++ b/mm/gup.c
@@ -2241,7 +2241,6 @@ static int __gup_device_huge(unsigned long pfn, unsigned long addr,
{
int nr_start = *nr;
struct dev_pagemap *pgmap = NULL;
- int ret = 1;
do {
struct page *page = pfn_to_page(pfn);
@@ -2249,14 +2248,12 @@ static int __gup_device_huge(unsigned long pfn, unsigned long addr,
pgmap = get_dev_pagemap(pfn, pgmap);
if (unlikely(!pgmap)) {
undo_dev_pagemap(nr, nr_start, flags, pages);
- ret = 0;
break;
}
SetPageReferenced(page);
pages[*nr] = page;
if (unlikely(!try_grab_page(page, flags))) {
undo_dev_pagemap(nr, nr_start, flags, pages);
- ret = 0;
break;
}
(*nr)++;
@@ -2264,7 +2261,7 @@ static int __gup_device_huge(unsigned long pfn, unsigned long addr,
} while (addr += PAGE_SIZE, addr != end);
put_dev_pagemap(pgmap);
- return ret;
+ return addr == end;
}
static int __gup_device_huge_pmd(pmd_t orig, pmd_t *pmdp, unsigned long addr,
thanks,
--
John Hubbard
NVIDIA
