From 5f47bdeb07b884cc8be2cc98557fe44b4b73c955 Mon Sep 17 00:00:00 2001
From: Sooyong Suk <s.suk@samsung.corp-partner.google.com>
Date: Tue, 8 Jul 2025 17:47:33 +0900
Subject: [PATCH] ANDROID: mm: add allocated and total pages for GCMA areas

For statistical support, let's add allocated and total size of GCMA
areas into gcma stats.

Bug: 410432482
Change-Id: Ifcae950fb96d11af560a95c85376fcf5156cd35c
Signed-off-by: Sooyong Suk <s.suk@samsung.corp-partner.google.com>
---
 include/linux/gcma.h |  2 ++
 mm/gcma.c            |  3 +++
 mm/gcma_sysfs.c      | 21 +++++++++++++++++++++
 mm/gcma_sysfs.h      |  3 +++
 4 files changed, 29 insertions(+)

diff --git a/include/linux/gcma.h b/include/linux/gcma.h
index 831180cd1483..a8aaf158f382 100644
--- a/include/linux/gcma.h
+++ b/include/linux/gcma.h
@@ -6,11 +6,13 @@
 
 #ifdef CONFIG_GCMA
 enum gcma_stat_type {
+	ALLOCATED_PAGE,
 	STORED_PAGE,
 	LOADED_PAGE,
 	EVICTED_PAGE,
 	CACHED_PAGE,
 	DISCARDED_PAGE,
+	TOTAL_PAGE,
 	NUM_OF_GCMA_STAT,
 };
 
diff --git a/mm/gcma.c b/mm/gcma.c
index 6fc98f3e9c2d..6a2eef774f80 100644
--- a/mm/gcma.c
+++ b/mm/gcma.c
@@ -307,6 +307,7 @@ int register_gcma_area(const char *name, phys_addr_t base, phys_addr_t size)
 	INIT_LIST_HEAD(&area->free_pages);
 	spin_lock_init(&area->free_pages_lock);
 
+	gcma_stat_add(TOTAL_PAGE, page_count);
 	for (i = 0; i < page_count; i++) {
 		page = pfn_to_page(pfn + i);
 		set_area_id(page, area_id);
@@ -621,6 +622,7 @@ void gcma_alloc_range(unsigned long start_pfn, unsigned long end_pfn)
 
 		__gcma_discard_range(area, s_pfn, e_pfn);
 	}
+	gcma_stat_add(ALLOCATED_PAGE, end_pfn - start_pfn + 1);
 }
 EXPORT_SYMBOL_GPL(gcma_alloc_range);
 
@@ -659,6 +661,7 @@ void gcma_free_range(unsigned long start_pfn, unsigned long end_pfn)
 	}
 
 	local_irq_enable();
+	gcma_stat_sub(ALLOCATED_PAGE, end_pfn - start_pfn + 1);
 }
 EXPORT_SYMBOL_GPL(gcma_free_range);
 
diff --git a/mm/gcma_sysfs.c b/mm/gcma_sysfs.c
index c1eaabbb6fdb..981cfa9b84aa 100644
--- a/mm/gcma_sysfs.c
+++ b/mm/gcma_sysfs.c
@@ -23,6 +23,11 @@ void gcma_stat_add(enum gcma_stat_type type, unsigned long delta)
 	atomic64_add(delta, &gcma_stats[type]);
 }
 
+void gcma_stat_sub(enum gcma_stat_type type, unsigned long delta)
+{
+	atomic64_sub(delta, &gcma_stats[type]);
+}
+
 u64 gcma_stat_get(enum gcma_stat_type type)
 {
 	return (u64)atomic64_read(&gcma_stats[type]);
@@ -36,6 +41,13 @@ EXPORT_SYMBOL_GPL(gcma_stat_get);
 #define GCMA_ATTR_RO(_name) \
 	static struct kobj_attribute _name##_attr = __ATTR_RO(_name)
 
+static ssize_t allocated_show(struct kobject *kobj,
+		struct kobj_attribute *attr, char *buf)
+{
+	return sysfs_emit(buf, "%llu\n", (u64)atomic64_read(&gcma_stats[ALLOCATED_PAGE]));
+}
+GCMA_ATTR_RO(allocated);
+
 static ssize_t stored_show(struct kobject *kobj,
 		struct kobj_attribute *attr, char *buf)
 {
@@ -71,12 +83,21 @@ static ssize_t discarded_show(struct kobject *kobj,
 }
 GCMA_ATTR_RO(discarded);
 
+static ssize_t total_show(struct kobject *kobj,
+		struct kobj_attribute *attr, char *buf)
+{
+	return sysfs_emit(buf, "%llu\n", (u64)atomic64_read(&gcma_stats[TOTAL_PAGE]));
+}
+GCMA_ATTR_RO(total);
+
 static struct attribute *gcma_attrs[] = {
+	&allocated_attr.attr,
 	&stored_attr.attr,
 	&loaded_attr.attr,
 	&evicted_attr.attr,
 	&cached_attr.attr,
 	&discarded_attr.attr,
+	&total_attr.attr,
 	NULL,
 };
 ATTRIBUTE_GROUPS(gcma);
diff --git a/mm/gcma_sysfs.h b/mm/gcma_sysfs.h
index cf93302b7e4f..b1dedf5804d8 100644
--- a/mm/gcma_sysfs.h
+++ b/mm/gcma_sysfs.h
@@ -6,11 +6,14 @@
 void gcma_stat_inc(enum gcma_stat_type type);
 void gcma_stat_dec(enum gcma_stat_type type);
 void gcma_stat_add(enum gcma_stat_type type, unsigned long delta);
+void gcma_stat_sub(enum gcma_stat_type type, unsigned long delta);
 #else /* CONFIG_GCMA_SYSFS */
 static inline void gcma_stat_inc(enum gcma_stat_type type) {}
 static inline void gcma_stat_dec(enum gcma_stat_type type) {}
 static inline void gcma_stat_add(enum gcma_stat_type type,
 				 unsigned long delta) {}
+static inline void gcma_stat_sub(enum gcma_stat_type type,
+				 unsigned long delta) {}
 #endif /* CONFIG_GCMA_SYSFS */
 
 #endif