mm/page_poison.c: replace bool variable with static key

Variable 'want_page_poisoning' is a switch deciding if page poisoning
should be enabled.  This patch changes it to be static key.

Signed-off-by: Mateusz Nosek <mateusznosek0@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Oscar Salvador <OSalvador@suse.com>
Link: https://lkml.kernel.org/r/20200921152931.938-1-mateusznosek0@gmail.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Mateusz Nosek 2020-10-15 20:07:33 -07:00 committed by Linus Torvalds
parent b94e02822d
commit 11c9c7edae
1 changed files with 15 additions and 5 deletions

View File

@ -8,13 +8,23 @@
#include <linux/ratelimit.h>
#include <linux/kasan.h>
static bool want_page_poisoning __read_mostly;
static DEFINE_STATIC_KEY_FALSE_RO(want_page_poisoning);
static int __init early_page_poison_param(char *buf)
{
if (!buf)
return -EINVAL;
return strtobool(buf, &want_page_poisoning);
int ret;
bool tmp;
ret = strtobool(buf, &tmp);
if (ret)
return ret;
if (tmp)
static_branch_enable(&want_page_poisoning);
else
static_branch_disable(&want_page_poisoning);
return 0;
}
early_param("page_poison", early_page_poison_param);
@ -31,7 +41,7 @@ bool page_poisoning_enabled(void)
* Page poisoning is debug page alloc for some arches. If
* either of those options are enabled, enable poisoning.
*/
return (want_page_poisoning ||
return (static_branch_unlikely(&want_page_poisoning) ||
(!IS_ENABLED(CONFIG_ARCH_SUPPORTS_DEBUG_PAGEALLOC) &&
debug_pagealloc_enabled()));
}