Commit 41c961b9 authored by Muchun Song's avatar Muchun Song Committed by Linus Torvalds
Browse files

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: default avatarMuchun Song <songmuchun@bytedance.com>
Reviewed-by: default avatarRoman Gushchin <guro@fb.com>
Acked-by: default avatarJohannes Weiner <hannes@cmpxchg.org>
Reviewed-by: default avatarShakeel 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: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent ea0eafea

include/linux/page-flags.h

+3 −1
Original line number Diff line number Diff line
@@ -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)

include/trace/events/page_ref.h

+2 −2
Original line number Diff line number Diff line
@@ -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)

lib/test_printf.c

+1 −1
Original line number Diff line number Diff line
@@ -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);

lib/vsprintf.c

+1 −1
Original line number Diff line number Diff line
@@ -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;