mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-09-12 13:55:32 +00:00
![SeongJae Park](/assets/img/avatar_default.png)
PG_idle and PG_young allow the two PTE Accessed bit users, Idle Page Tracking and the reclaim logic concurrently work while not interfering with each other. That is, when they need to clear the Accessed bit, they set PG_young to represent the previous state of the bit, respectively. And when they need to read the bit, if the bit is cleared, they further read the PG_young to know whether the other has cleared the bit meanwhile or not. For yet another user of the PTE Accessed bit, we could add another page flag, or extend the mechanism to use the flags. For the DAMON usecase, however, we don't need to do that just yet. IDLE_PAGE_TRACKING and DAMON are mutually exclusive, so there's only ever going to be one user of the current set of flags. In this commit, we split out the CONFIG options to allow for the use of PG_young and PG_idle outside of idle page tracking. In the next commit, DAMON's reference implementation of the virtual memory address space monitoring primitives will use it. [sjpark@amazon.de: set PAGE_EXTENSION for non-64BIT] Link: https://lkml.kernel.org/r/20210806095153.6444-1-sj38.park@gmail.com [akpm@linux-foundation.org: tweak Kconfig text] [sjpark@amazon.de: hide PAGE_IDLE_FLAG from users] Link: https://lkml.kernel.org/r/20210813081238.34705-1-sj38.park@gmail.com Link: https://lkml.kernel.org/r/20210716081449.22187-5-sj38.park@gmail.com Signed-off-by: SeongJae Park <sjpark@amazon.de> Reviewed-by: Shakeel Butt <shakeelb@google.com> Reviewed-by: Fernand Sieber <sieberf@amazon.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Amit Shah <amit@kernel.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Brendan Higgins <brendanhiggins@google.com> Cc: David Hildenbrand <david@redhat.com> Cc: David Rientjes <rientjes@google.com> Cc: David Woodhouse <dwmw@amazon.com> Cc: Fan Du <fan.du@intel.com> Cc: Greg Kroah-Hartman <greg@kroah.com> Cc: Greg Thelen <gthelen@google.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Joe Perches <joe@perches.com> Cc: Jonathan Cameron <Jonathan.Cameron@huawei.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Leonard Foerster <foersleo@amazon.de> Cc: Marco Elver <elver@google.com> Cc: Markus Boehme <markubo@amazon.de> Cc: Maximilian Heyne <mheyne@amazon.de> Cc: Mel Gorman <mgorman@suse.de> Cc: Minchan Kim <minchan@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@surriel.com> Cc: Shuah Khan <shuah@kernel.org> Cc: Steven Rostedt (VMware) <rostedt@goodmis.org> Cc: Vladimir Davydov <vdavydov.dev@gmail.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
140 lines
2.6 KiB
C
140 lines
2.6 KiB
C
/* SPDX-License-Identifier: GPL-2.0 */
|
|
#ifndef _LINUX_MM_PAGE_IDLE_H
|
|
#define _LINUX_MM_PAGE_IDLE_H
|
|
|
|
#include <linux/bitops.h>
|
|
#include <linux/page-flags.h>
|
|
#include <linux/page_ext.h>
|
|
|
|
#ifdef CONFIG_PAGE_IDLE_FLAG
|
|
|
|
#ifdef CONFIG_64BIT
|
|
static inline bool page_is_young(struct page *page)
|
|
{
|
|
return PageYoung(page);
|
|
}
|
|
|
|
static inline void set_page_young(struct page *page)
|
|
{
|
|
SetPageYoung(page);
|
|
}
|
|
|
|
static inline bool test_and_clear_page_young(struct page *page)
|
|
{
|
|
return TestClearPageYoung(page);
|
|
}
|
|
|
|
static inline bool page_is_idle(struct page *page)
|
|
{
|
|
return PageIdle(page);
|
|
}
|
|
|
|
static inline void set_page_idle(struct page *page)
|
|
{
|
|
SetPageIdle(page);
|
|
}
|
|
|
|
static inline void clear_page_idle(struct page *page)
|
|
{
|
|
ClearPageIdle(page);
|
|
}
|
|
#else /* !CONFIG_64BIT */
|
|
/*
|
|
* If there is not enough space to store Idle and Young bits in page flags, use
|
|
* page ext flags instead.
|
|
*/
|
|
extern struct page_ext_operations page_idle_ops;
|
|
|
|
static inline bool page_is_young(struct page *page)
|
|
{
|
|
struct page_ext *page_ext = lookup_page_ext(page);
|
|
|
|
if (unlikely(!page_ext))
|
|
return false;
|
|
|
|
return test_bit(PAGE_EXT_YOUNG, &page_ext->flags);
|
|
}
|
|
|
|
static inline void set_page_young(struct page *page)
|
|
{
|
|
struct page_ext *page_ext = lookup_page_ext(page);
|
|
|
|
if (unlikely(!page_ext))
|
|
return;
|
|
|
|
set_bit(PAGE_EXT_YOUNG, &page_ext->flags);
|
|
}
|
|
|
|
static inline bool test_and_clear_page_young(struct page *page)
|
|
{
|
|
struct page_ext *page_ext = lookup_page_ext(page);
|
|
|
|
if (unlikely(!page_ext))
|
|
return false;
|
|
|
|
return test_and_clear_bit(PAGE_EXT_YOUNG, &page_ext->flags);
|
|
}
|
|
|
|
static inline bool page_is_idle(struct page *page)
|
|
{
|
|
struct page_ext *page_ext = lookup_page_ext(page);
|
|
|
|
if (unlikely(!page_ext))
|
|
return false;
|
|
|
|
return test_bit(PAGE_EXT_IDLE, &page_ext->flags);
|
|
}
|
|
|
|
static inline void set_page_idle(struct page *page)
|
|
{
|
|
struct page_ext *page_ext = lookup_page_ext(page);
|
|
|
|
if (unlikely(!page_ext))
|
|
return;
|
|
|
|
set_bit(PAGE_EXT_IDLE, &page_ext->flags);
|
|
}
|
|
|
|
static inline void clear_page_idle(struct page *page)
|
|
{
|
|
struct page_ext *page_ext = lookup_page_ext(page);
|
|
|
|
if (unlikely(!page_ext))
|
|
return;
|
|
|
|
clear_bit(PAGE_EXT_IDLE, &page_ext->flags);
|
|
}
|
|
#endif /* CONFIG_64BIT */
|
|
|
|
#else /* !CONFIG_PAGE_IDLE_FLAG */
|
|
|
|
static inline bool page_is_young(struct page *page)
|
|
{
|
|
return false;
|
|
}
|
|
|
|
static inline void set_page_young(struct page *page)
|
|
{
|
|
}
|
|
|
|
static inline bool test_and_clear_page_young(struct page *page)
|
|
{
|
|
return false;
|
|
}
|
|
|
|
static inline bool page_is_idle(struct page *page)
|
|
{
|
|
return false;
|
|
}
|
|
|
|
static inline void set_page_idle(struct page *page)
|
|
{
|
|
}
|
|
|
|
static inline void clear_page_idle(struct page *page)
|
|
{
|
|
}
|
|
|
|
#endif /* CONFIG_PAGE_IDLE_FLAG */
|
|
|
|
#endif /* _LINUX_MM_PAGE_IDLE_H */
|