mgm: sysfs node to manually retain SLC partitionandroid-15-beta-1_r0.6android-15-beta-1_r0.4android-15-beta-1_r0.2android-15-beta-1_r0.1android-gs-tangorpro-5.10-android15-dpandroid-gs-tangorpro-5.10-android15-betaandroid-gs-pantah-5.10-android15-dpandroid-gs-pantah-5.10-android15-betaandroid-gs-felix-5.10-android15-dpandroid-gs-felix-5.10-android15-betaandroid-gs-bluejay-5.10-android15-dpandroid-gs-bluejay-5.10-android15-beta

Add sysfs node to manually pin the SLC partition in the enabled
state, which is useful when profiling SLC performance.

Bug: 313458962
Test: echo 1 > /sys/kernel/pixel_stat/gpu/mem/slc_pin_partition
Signed-off-by: Jack Diver <diverj@google.com>
(cherry picked from https://partner-android-review.googlesource.com/q/commit:4f276f684312fa600b038553e1ad2b357034dd91)
Merged-In: I5d316d9277c7f514039581f95188f14f86bd87c2
Change-Id: I5d316d9277c7f514039581f95188f14f86bd87c2

4 files changed, 54 insertions, 1 deletions

diff --git a/mali_pixel/Documentation/ABI/testing/sysfs-kernel-pixel_stat-gpu b/mali_pixel/Documentation/ABI/testing/sysfs-kernel-pixel_stat-gpu
new file mode 100644
index 0000000..1d3bc11
--- /dev/null
+++ b/mali_pixel/Documentation/ABI/testing/sysfs-kernel-pixel_stat-gpu
@@ -0,0 +1,7 @@
+What:		/sys/kernel/pixel_stat/gpu/mem/slc_pin_partition
+Date:		Feb 2024
+Contact:	"Jack Diver" <diverj@google.com>
+Description:
+		Write-only node to manually pin the SLC partition in the enabled
+		state. This useful when profiling SLC performance.
+
diff --git a/mali_pixel/memory_group_manager.c b/mali_pixel/memory_group_manager.c
index 81abfb4..9076a65 100644
--- a/mali_pixel/memory_group_manager.c
+++ b/mali_pixel/memory_group_manager.c
@@ -254,6 +254,8 @@ extern struct kobject *pixel_stat_gpu_kobj;
 
 #define MGM_ATTR_RO(_name) \
 	static struct kobj_attribute _name##_attr = __ATTR_RO(_name)
+#define MGM_ATTR_WO(_name) \
+	static struct kobj_attribute _name##_attr = __ATTR_WO(_name)
 
 static ssize_t total_page_count_show(struct kobject *kobj,
 				struct kobj_attribute *attr, char *buf)
@@ -296,10 +298,31 @@ static ssize_t large_page_count_show(struct kobject *kobj,
 }
 MGM_ATTR_RO(large_page_count);
 
+static ssize_t slc_pin_partition_store(struct kobject* kobj,
+                                       struct kobj_attribute* attr,
+                                       const char* buf,
+                                       size_t count)
+{
+	struct mgm_groups *data = container_of(kobj, struct mgm_groups, kobj);
+	bool pin;
+
+	if (!data)
+		return -ENODEV;
+
+	if (kstrtobool(buf, &pin))
+		return -EINVAL;
+
+	slc_pin(&data->slc_data, pin);
+
+	return count;
+}
+MGM_ATTR_WO(slc_pin_partition);
+
 static struct attribute *mgm_attrs[] = {
 	&total_page_count_attr.attr,
 	&small_page_count_attr.attr,
 	&large_page_count_attr.attr,
+	&slc_pin_partition_attr.attr,
 	NULL,
 };
 ATTRIBUTE_GROUPS(mgm);
diff --git a/mali_pixel/pixel_slc.c b/mali_pixel/pixel_slc.c
index f06d495..45506ab 100644
--- a/mali_pixel/pixel_slc.c
+++ b/mali_pixel/pixel_slc.c
@@ -56,7 +56,8 @@ static bool partition_required(struct slc_partition *pt)
 {
 	lockdep_assert_held(&pt->lock);
 
-	return atomic_read(&pt->refcount) && (pt->signal >= PARTITION_ENABLE_THRESHOLD);
+	return (atomic_read(&pt->refcount) && (pt->signal >= PARTITION_ENABLE_THRESHOLD)) ||
+	       pt->pinned;
 }
 
 /**
@@ -251,6 +252,22 @@ void slc_update_signal(struct slc_data *data, u64 signal)
 	spin_unlock_irqrestore(&pt->lock, flags);
 }
 
+void slc_pin(struct slc_data *data, bool pin)
+{
+	struct slc_partition *pt = &data->partition;
+	unsigned long flags;
+
+	spin_lock_irqsave(&pt->lock, flags);
+
+	pt->pinned = pin;
+	if (pin)
+		enable_partition(data, pt);
+	else if (!partition_required(pt))
+		queue_disable_worker(data);
+
+	spin_unlock_irqrestore(&pt->lock, flags);
+}
+
 /**
  * init_partition - Register and initialize a partition with the SLC driver.
  *
@@ -291,6 +308,7 @@ static int init_partition(struct slc_data *data, struct slc_partition *pt, u32 i
 		.enabled = false,
 		.refcount = ATOMIC_INIT(0),
 		.signal = 0,
+		.pinned = false,
 	};
 	spin_lock_init(&pt->lock);
 
diff --git a/mali_pixel/pixel_slc.h b/mali_pixel/pixel_slc.h
index 1ac3da4..cb8e90d 100644
--- a/mali_pixel/pixel_slc.h
+++ b/mali_pixel/pixel_slc.h
@@ -54,6 +54,9 @@ struct slc_partition {
 
 	/** @signal: Partition enable/disable signal from SLC governor */
 	u64 signal;
+
+	/** @pinned: Is the partition pinned to the enabled state */
+	bool pinned;
 };
 
 /**
@@ -88,6 +91,8 @@ void slc_inc_refcount(struct slc_data *data);
 
 void slc_dec_refcount(struct slc_data *data);
 
+void slc_pin(struct slc_data *data, bool pin);
+
 void slc_update_signal(struct slc_data *data, u64 signal);
 
 #endif /* _PIXEL_SLC_H_ */