mm: introduce PAGEFLAGS_MASK to replace ((1UL << NR_PAGEFLAGS) - 1)

Instead of hard-coding ((1UL << NR_PAGEFLAGS) - 1) everywhere, introducing
PAGEFLAGS_MASK to make the code clear to get the page flags.

Link: https://lkml.kernel.org/r/20210819150712.59948-1-songmuchun@bytedance.com
Signed-off-by: Muchun Song <songmuchun@bytedance.com>
Reviewed-by: Roman Gushchin <guro@fb.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Muchun Song 2021-09-07 19:56:15 -07:00 committed by Linus Torvalds
parent ea0eafead4
commit 41c961b901
4 changed files with 7 additions and 5 deletions

View File

@ -178,6 +178,8 @@ enum pageflags {
PG_reported = PG_uptodate,
};
#define PAGEFLAGS_MASK ((1UL << NR_PAGEFLAGS) - 1)
#ifndef __GENERATING_BOUNDS_H
static inline unsigned long _compound_head(const struct page *page)
@ -859,7 +861,7 @@ static inline void ClearPageSlabPfmemalloc(struct page *page)
* alloc-free cycle to prevent from reusing the page.
*/
#define PAGE_FLAGS_CHECK_AT_PREP \
(((1UL << NR_PAGEFLAGS) - 1) & ~__PG_HWPOISON)
(PAGEFLAGS_MASK & ~__PG_HWPOISON)
#define PAGE_FLAGS_PRIVATE \
(1UL << PG_private | 1UL << PG_private_2)

View File

@ -38,7 +38,7 @@ DECLARE_EVENT_CLASS(page_ref_mod_template,
TP_printk("pfn=0x%lx flags=%s count=%d mapcount=%d mapping=%p mt=%d val=%d",
__entry->pfn,
show_page_flags(__entry->flags & ((1UL << NR_PAGEFLAGS) - 1)),
show_page_flags(__entry->flags & PAGEFLAGS_MASK),
__entry->count,
__entry->mapcount, __entry->mapping, __entry->mt,
__entry->val)
@ -88,7 +88,7 @@ DECLARE_EVENT_CLASS(page_ref_mod_and_test_template,
TP_printk("pfn=0x%lx flags=%s count=%d mapcount=%d mapping=%p mt=%d val=%d ret=%d",
__entry->pfn,
show_page_flags(__entry->flags & ((1UL << NR_PAGEFLAGS) - 1)),
show_page_flags(__entry->flags & PAGEFLAGS_MASK),
__entry->count,
__entry->mapcount, __entry->mapping, __entry->mt,
__entry->val, __entry->ret)

View File

@ -614,7 +614,7 @@ page_flags_test(int section, int node, int zone, int last_cpupid,
bool append = false;
int i;
flags &= BIT(NR_PAGEFLAGS) - 1;
flags &= PAGEFLAGS_MASK;
if (flags) {
page_flags |= flags;
snprintf(cmp_buf + size, BUF_SIZE - size, "%s", name);

View File

@ -2019,7 +2019,7 @@ static const struct page_flags_fields pff[] = {
static
char *format_page_flags(char *buf, char *end, unsigned long flags)
{
unsigned long main_flags = flags & (BIT(NR_PAGEFLAGS) - 1);
unsigned long main_flags = flags & PAGEFLAGS_MASK;
bool append = false;
int i;