[RFC v10 06/13] mm/damon/vaddr: Separate commonly usable functions

[SeongJae Park <sjpark@amazon.com>]

From: SeongJae Park <sjpark@amazon.de>

This commit 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 in the following
commit.

Signed-off-by: SeongJae Park <sjpark@amazon.de>
---
 mm/damon/Makefile       |   2 +-
 mm/damon/prmtv-common.c | 104 ++++++++++++++++++++++++++++++++++++++
 mm/damon/prmtv-common.h |  21 ++++++++
 mm/damon/vaddr.c        | 108 +---------------------------------------
 4 files changed, 128 insertions(+), 107 deletions(-)
 create mode 100644 mm/damon/prmtv-common.c
 create mode 100644 mm/damon/prmtv-common.h

diff --git a/mm/damon/Makefile b/mm/damon/Makefile
index fed4be3bace3..99b1bfe01ff5 100644
--- a/mm/damon/Makefile
+++ b/mm/damon/Makefile
@@ -1,5 +1,5 @@
 # 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
diff --git a/mm/damon/prmtv-common.c b/mm/damon/prmtv-common.c
new file mode 100644
index 000000000000..6cdb96cbc9ef
--- /dev/null
+++ b/mm/damon/prmtv-common.c
@@ -0,0 +1,104 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Common Primitives for Data Access Monitoring
+ *
+ * Author: SeongJae Park <sjpark@amazon.de>
+ */
+
+#include "prmtv-common.h"
+
+static void damon_ptep_mkold(pte_t *pte, struct mm_struct *mm,
+			     unsigned long addr)
+{
+	bool referenced = false;
+	struct page *page = pte_page(*pte);
+
+	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);
+}
+
+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 = pmd_page(*pmd);
+
+	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);
+#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
+}
+
+void damon_va_mkold(struct mm_struct *mm, unsigned long addr)
+{
+	pte_t *pte = NULL;
+	pmd_t *pmd = NULL;
+	spinlock_t *ptl;
+
+	if (follow_pte_pmd(mm, addr, NULL, &pte, &pmd, &ptl))
+		return;
+
+	if (pte) {
+		damon_ptep_mkold(pte, mm, addr);
+		pte_unmap_unlock(pte, ptl);
+	} else {
+		damon_pmdp_mkold(pmd, mm, addr);
+		spin_unlock(ptl);
+	}
+}
+
+bool damon_va_young(struct mm_struct *mm, unsigned long addr,
+			unsigned long *page_sz)
+{
+	pte_t *pte = NULL;
+	pmd_t *pmd = NULL;
+	spinlock_t *ptl;
+	bool young = false;
+
+	if (follow_pte_pmd(mm, addr, NULL, &pte, &pmd, &ptl))
+		return false;
+
+	*page_sz = PAGE_SIZE;
+	if (pte) {
+		young = pte_young(*pte);
+		if (!young)
+			young = !page_is_idle(pte_page(*pte));
+		pte_unmap_unlock(pte, ptl);
+		return young;
+	}
+
+#ifdef CONFIG_TRANSPARENT_HUGEPAGE
+	young = pmd_young(*pmd);
+	if (!young)
+		young = !page_is_idle(pmd_page(*pmd));
+	spin_unlock(ptl);
+	*page_sz = ((1UL) << HPAGE_PMD_SHIFT);
+#endif	/* CONFIG_TRANSPARENT_HUGEPAGE */
+
+	return young;
+}
diff --git a/mm/damon/prmtv-common.h b/mm/damon/prmtv-common.h
new file mode 100644
index 000000000000..a66a6139b4fc
--- /dev/null
+++ b/mm/damon/prmtv-common.h
@@ -0,0 +1,21 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Common Primitives for Data Access Monitoring
+ *
+ * Author: SeongJae Park <sjpark@amazon.de>
+ */
+
+#include <linux/damon.h>
+#include <linux/mm.h>
+#include <linux/mmu_notifier.h>
+#include <linux/page_idle.h>
+#include <linux/random.h>
+#include <linux/sched/mm.h>
+#include <linux/slab.h>
+
+/* Get a random number in [l, r) */
+#define damon_rand(l, r) (l + prandom_u32_max(r - l))
+
+void damon_va_mkold(struct mm_struct *mm, unsigned long addr);
+bool damon_va_young(struct mm_struct *mm, unsigned long addr,
+			unsigned long *page_sz);
diff --git a/mm/damon/vaddr.c b/mm/damon/vaddr.c
index 2075f07f728b..915b12329c6e 100644
--- a/mm/damon/vaddr.c
+++ b/mm/damon/vaddr.c
@@ -8,22 +8,14 @@
 #define pr_fmt(fmt) "damon-va: " fmt
 
 #include <asm-generic/mman-common.h>
-#include <linux/damon.h>
-#include <linux/mm.h>
-#include <linux/mmu_notifier.h>
-#include <linux/page_idle.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.
@@ -370,71 +362,6 @@ void damon_va_update_regions(struct damon_ctx *ctx)
 	}
 }
 
-static void damon_ptep_mkold(pte_t *pte, struct mm_struct *mm,
-			     unsigned long addr)
-{
-	bool referenced = false;
-	struct page *page = pte_page(*pte);
-
-	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);
-}
-
-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 = pmd_page(*pmd);
-
-	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);
-#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
-}
-
-static void damon_va_mkold(struct mm_struct *mm, unsigned long addr)
-{
-	pte_t *pte = NULL;
-	pmd_t *pmd = NULL;
-	spinlock_t *ptl;
-
-	if (follow_pte_pmd(mm, addr, NULL, &pte, &pmd, &ptl))
-		return;
-
-	if (pte) {
-		damon_ptep_mkold(pte, mm, addr);
-		pte_unmap_unlock(pte, ptl);
-	} else {
-		damon_pmdp_mkold(pmd, mm, addr);
-		spin_unlock(ptl);
-	}
-}
-
 /*
  * Functions for the access checking of the regions
  */
@@ -463,37 +390,6 @@ void damon_va_prepare_access_checks(struct damon_ctx *ctx)
 	}
 }
 
-static bool damon_va_young(struct mm_struct *mm, unsigned long addr,
-			unsigned long *page_sz)
-{
-	pte_t *pte = NULL;
-	pmd_t *pmd = NULL;
-	spinlock_t *ptl;
-	bool young = false;
-
-	if (follow_pte_pmd(mm, addr, NULL, &pte, &pmd, &ptl))
-		return false;
-
-	*page_sz = PAGE_SIZE;
-	if (pte) {
-		young = pte_young(*pte);
-		if (!young)
-			young = !page_is_idle(pte_page(*pte));
-		pte_unmap_unlock(pte, ptl);
-		return young;
-	}
-
-#ifdef CONFIG_TRANSPARENT_HUGEPAGE
-	young = pmd_young(*pmd);
-	if (!young)
-		young = !page_is_idle(pmd_page(*pmd));
-	spin_unlock(ptl);
-	*page_sz = ((1UL) << HPAGE_PMD_SHIFT);
-#endif	/* CONFIG_TRANSPARENT_HUGEPAGE */
-
-	return young;
-}
-
 /*
  * Check whether the region was accessed after the last preparation
  *
-- 
2.17.1