Commit 46c3a0ac authored by SeongJae Park's avatar SeongJae Park Committed by Linus Torvalds
Browse files

mm/damon/vaddr: separate commonly usable functions 

This moves functions in the default virtual address spaces monitoring
primitives that commonly usable from other address spaces like physical
address space into a header file.  Those will be reused by the physical
address space monitoring primitives which will be implemented by the
following commit.

[sj@kernel.org: include 'highmem.h' to fix a build failure]
  Link: https://lkml.kernel.org/r/20211014110848.5204-1-sj@kernel.org

Link: https://lkml.kernel.org/r/20211012205711.29216-5-sj@kernel.org


Signed-off-by: default avatarSeongJae Park <sj@kernel.org>
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 Rienjes <rientjes@google.com>
Cc: David Woodhouse <dwmw@amazon.com>
Cc: Greg Thelen <gthelen@google.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: Shakeel Butt <shakeelb@google.com>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent c2fe4987

mm/damon/Makefile

+1 −1
Original line number Diff line number Diff line 
# SPDX-License-Identifier: GPL-2.0



obj-$(CONFIG_DAMON)		:= core.o

obj-$(CONFIG_DAMON_VADDR)	+= vaddr.o

obj-$(CONFIG_DAMON_VADDR)	+= prmtv-common.o vaddr.o

obj-$(CONFIG_DAMON_DBGFS)	+= dbgfs.o

mm/damon/prmtv-common.c

0 → 100644
+87 −0
Original line number Diff line number Diff line 
// SPDX-License-Identifier: GPL-2.0

/*

 * Common Primitives for Data Access Monitoring

 *

 * Author: SeongJae Park <sj@kernel.org>

 */



#include <linux/mmu_notifier.h>

#include <linux/page_idle.h>

#include <linux/pagemap.h>

#include <linux/rmap.h>



#include "prmtv-common.h"



/*

 * Get an online page for a pfn if it's in the LRU list.  Otherwise, returns

 * NULL.

 *

 * The body of this function is stolen from the 'page_idle_get_page()'.  We

 * steal rather than reuse it because the code is quite simple.

 */

struct page *damon_get_page(unsigned long pfn)

{

	struct page *page = pfn_to_online_page(pfn);



	if (!page || !PageLRU(page) || !get_page_unless_zero(page))

		return NULL;



	if (unlikely(!PageLRU(page))) {

		put_page(page);

		page = NULL;

	}

	return page;

}



void damon_ptep_mkold(pte_t *pte, struct mm_struct *mm, unsigned long addr)

{

	bool referenced = false;

	struct page *page = damon_get_page(pte_pfn(*pte));



	if (!page)

		return;



	if (pte_young(*pte)) {

		referenced = true;

		*pte = pte_mkold(*pte);

	}



#ifdef CONFIG_MMU_NOTIFIER

	if (mmu_notifier_clear_young(mm, addr, addr + PAGE_SIZE))

		referenced = true;

#endif /* CONFIG_MMU_NOTIFIER */



	if (referenced)

		set_page_young(page);



	set_page_idle(page);

	put_page(page);

}



void damon_pmdp_mkold(pmd_t *pmd, struct mm_struct *mm, unsigned long addr)

{

#ifdef CONFIG_TRANSPARENT_HUGEPAGE

	bool referenced = false;

	struct page *page = damon_get_page(pmd_pfn(*pmd));



	if (!page)

		return;



	if (pmd_young(*pmd)) {

		referenced = true;

		*pmd = pmd_mkold(*pmd);

	}



#ifdef CONFIG_MMU_NOTIFIER

	if (mmu_notifier_clear_young(mm, addr,

				addr + ((1UL) << HPAGE_PMD_SHIFT)))

		referenced = true;

#endif /* CONFIG_MMU_NOTIFIER */



	if (referenced)

		set_page_young(page);



	set_page_idle(page);

	put_page(page);

#endif /* CONFIG_TRANSPARENT_HUGEPAGE */

}

mm/damon/prmtv-common.h

0 → 100644
+17 −0
Original line number Diff line number Diff line 
/* SPDX-License-Identifier: GPL-2.0 */

/*

 * Common Primitives for Data Access Monitoring

 *

 * Author: SeongJae Park <sj@kernel.org>

 */



#include <linux/damon.h>

#include <linux/random.h>



/* Get a random number in [l, r) */

#define damon_rand(l, r) (l + prandom_u32_max(r - l))



struct page *damon_get_page(unsigned long pfn);



void damon_ptep_mkold(pte_t *pte, struct mm_struct *mm, unsigned long addr);

void damon_pmdp_mkold(pmd_t *pmd, struct mm_struct *mm, unsigned long addr);

mm/damon/vaddr.c

+3 −85
Original line number Diff line number Diff line
@@ -8,25 +8,19 @@ 
#define pr_fmt(fmt) "damon-va: " fmt



#include <asm-generic/mman-common.h>

#include <linux/damon.h>

#include <linux/highmem.h>

#include <linux/hugetlb.h>

#include <linux/mm.h>

#include <linux/mmu_notifier.h>

#include <linux/highmem.h>

#include <linux/page_idle.h>

#include <linux/pagewalk.h>

#include <linux/random.h>

#include <linux/sched/mm.h>

#include <linux/slab.h>



#include "prmtv-common.h"



#ifdef CONFIG_DAMON_VADDR_KUNIT_TEST

#undef DAMON_MIN_REGION

#define DAMON_MIN_REGION 1

#endif



/* Get a random number in [l, r) */

#define damon_rand(l, r) (l + prandom_u32_max(r - l))



/*

 * 't->id' should be the pointer to the relevant 'struct pid' having reference

 * count.  Caller must put the returned task, unless it is NULL.
@@ -373,82 +367,6 @@ void damon_va_update(struct damon_ctx *ctx) 
	}

}



/*

 * Get an online page for a pfn if it's in the LRU list.  Otherwise, returns

 * NULL.

 *

 * The body of this function is stolen from the 'page_idle_get_page()'.  We

 * steal rather than reuse it because the code is quite simple.

 */

static struct page *damon_get_page(unsigned long pfn)

{

	struct page *page = pfn_to_online_page(pfn);



	if (!page || !PageLRU(page) || !get_page_unless_zero(page))

		return NULL;



	if (unlikely(!PageLRU(page))) {

		put_page(page);

		page = NULL;

	}

	return page;

}



static void damon_ptep_mkold(pte_t *pte, struct mm_struct *mm,

			     unsigned long addr)

{

	bool referenced = false;

	struct page *page = damon_get_page(pte_pfn(*pte));



	if (!page)

		return;



	if (pte_young(*pte)) {

		referenced = true;

		*pte = pte_mkold(*pte);

	}



#ifdef CONFIG_MMU_NOTIFIER

	if (mmu_notifier_clear_young(mm, addr, addr + PAGE_SIZE))

		referenced = true;

#endif /* CONFIG_MMU_NOTIFIER */



	if (referenced)

		set_page_young(page);



	set_page_idle(page);

	put_page(page);

}



static void damon_pmdp_mkold(pmd_t *pmd, struct mm_struct *mm,

			     unsigned long addr)

{

#ifdef CONFIG_TRANSPARENT_HUGEPAGE

	bool referenced = false;

	struct page *page = damon_get_page(pmd_pfn(*pmd));



	if (!page)

		return;



	if (pmd_young(*pmd)) {

		referenced = true;

		*pmd = pmd_mkold(*pmd);

	}



#ifdef CONFIG_MMU_NOTIFIER

	if (mmu_notifier_clear_young(mm, addr,

				addr + ((1UL) << HPAGE_PMD_SHIFT)))

		referenced = true;

#endif /* CONFIG_MMU_NOTIFIER */



	if (referenced)

		set_page_young(page);



	set_page_idle(page);

	put_page(page);

#endif /* CONFIG_TRANSPARENT_HUGEPAGE */

}



static int damon_mkold_pmd_entry(pmd_t *pmd, unsigned long addr,

		unsigned long next, struct mm_walk *walk)

{