[PATCH v3 0/4] Panthor BO tagging and GEMS debug display

[PATCH v3 0/4] Panthor BO tagging and GEMS debug display

[Adrián Larumbe]

This patch series is aimed at providing UM with detailed memory profiling
information in debug builds. It is achieved through a device-wide list of
DRM GEM objects, and also implementing the ability to label BO's from UM
through a new IOCTL.

The new debugfs file shows a list of driver DRM GEM objects in tabular mode.
To visualise it, cat sudo cat /sys/kernel/debug/dri/*.gpu/gems.
To test this functionality from UM, please refer to this Mesa patch series:

https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/34224

Changelog:
 v3:
  - Replaced kfree() with kfree_const() when freeing a bo label
  - Rearranged functions for delaing with GEMs list adding and deleting
  - Changed Kernel BO labelling format not to include quotes
  - Return error in labelling ioctl when string length is too long


Adrián Larumbe (4):
  drm/panthor: Introduce BO labeling
  drm/panthor: Add driver IOCTL for setting BO labels
  drm/panthor: show device-wide list of DRM GEM objects over DebugFS
  drm/panthor: Display heap chunk entries in DebugFS GEMS file

 drivers/gpu/drm/panthor/panthor_device.c |   5 +
 drivers/gpu/drm/panthor/panthor_device.h |  11 ++
 drivers/gpu/drm/panthor/panthor_drv.c    |  66 ++++++++++
 drivers/gpu/drm/panthor/panthor_gem.c    | 158 +++++++++++++++++++++++
 drivers/gpu/drm/panthor/panthor_gem.h    |  60 +++++++++
 drivers/gpu/drm/panthor/panthor_heap.c   |   3 +
 include/uapi/drm/panthor_drm.h           |  19 +++
 7 files changed, 322 insertions(+)

--
2.48.1

[PATCH v3 1/4] drm/panthor: Introduce BO labeling

[Adrián Larumbe]

Add a new character string Panthor BO field, and a function that allows
setting it from within the driver.

Driver takes care of freeing the string when it's replaced or no longer
needed at object destruction time, but allocating it is the responsibility
of callers.

Signed-off-by: Adrián Larumbe <adrian.larumbe@collabora.com>
---
 drivers/gpu/drm/panthor/panthor_gem.c | 38 +++++++++++++++++++++++++++
 drivers/gpu/drm/panthor/panthor_gem.h | 17 ++++++++++++
 2 files changed, 55 insertions(+)

diff --git a/drivers/gpu/drm/panthor/panthor_gem.c b/drivers/gpu/drm/panthor/panthor_gem.c
index 8244a4e6c2a2..7d017f9d1d52 100644
--- a/drivers/gpu/drm/panthor/panthor_gem.c
+++ b/drivers/gpu/drm/panthor/panthor_gem.c
@@ -18,6 +18,14 @@ static void panthor_gem_free_object(struct drm_gem_object *obj)
 	struct panthor_gem_object *bo = to_panthor_bo(obj);
 	struct drm_gem_object *vm_root_gem = bo->exclusive_vm_root_gem;
 
+	/*
+	 * Label might have been allocated with kstrdup_const(),
+	 * we need to take that into account when freeing the memory
+	 */
+	kfree_const(bo->label.str);
+
+	mutex_destroy(&bo->label.lock);
+
 	drm_gem_free_mmap_offset(&bo->base.base);
 	mutex_destroy(&bo->gpuva_list_lock);
 	drm_gem_shmem_free(&bo->base);
@@ -196,6 +204,7 @@ struct drm_gem_object *panthor_gem_create_object(struct drm_device *ddev, size_t
 	obj->base.map_wc = !ptdev->coherent;
 	mutex_init(&obj->gpuva_list_lock);
 	drm_gem_gpuva_set_lock(&obj->base.base, &obj->gpuva_list_lock);
+	mutex_init(&obj->label.lock);
 
 	return &obj->base.base;
 }
@@ -247,3 +256,32 @@ panthor_gem_create_with_handle(struct drm_file *file,
 
 	return ret;
 }
+
+void
+panthor_gem_bo_set_label(struct drm_gem_object *obj, const char *label)
+{
+	struct panthor_gem_object *bo = to_panthor_bo(obj);
+	const char *old_label;
+
+	mutex_lock(&bo->label.lock);
+	old_label = bo->label.str;
+	bo->label.str = label;
+	mutex_unlock(&bo->label.lock);
+
+	kfree(old_label);
+}
+
+void
+panthor_gem_kernel_bo_set_label(struct panthor_kernel_bo *bo, const char *label)
+{
+	const char *str;
+
+	str = kstrdup_const(label, GFP_KERNEL);
+	if (!str) {
+		/* Failing to allocate memory for a label isn't a fatal condition */
+		drm_warn(bo->obj->dev, "Not enough memory to allocate BO label");
+		return;
+	}
+
+	panthor_gem_bo_set_label(bo->obj, kstrdup_const(str, GFP_KERNEL));
+}
diff --git a/drivers/gpu/drm/panthor/panthor_gem.h b/drivers/gpu/drm/panthor/panthor_gem.h
index 5749ef2ebe03..0582826b341a 100644
--- a/drivers/gpu/drm/panthor/panthor_gem.h
+++ b/drivers/gpu/drm/panthor/panthor_gem.h
@@ -46,6 +46,20 @@ struct panthor_gem_object {
 
 	/** @flags: Combination of drm_panthor_bo_flags flags. */
 	u32 flags;
+
+	/**
+	 * @label: BO tagging fields. The label can be assigned within the
+	 * driver itself or through a specific IOCTL.
+	 */
+	struct {
+		/**
+		 * @label.str: Pointer to NULL-terminated string,
+		 */
+		const char *str;
+
+		/** @lock.str: Protects access to the @label.str field. */
+		struct mutex lock;
+	} label;
 };
 
 /**
@@ -91,6 +105,9 @@ panthor_gem_create_with_handle(struct drm_file *file,
 			       struct panthor_vm *exclusive_vm,
 			       u64 *size, u32 flags, uint32_t *handle);
 
+void panthor_gem_bo_set_label(struct drm_gem_object *obj, const char *label);
+void panthor_gem_kernel_bo_set_label(struct panthor_kernel_bo *bo, const char *label);
+
 static inline u64
 panthor_kernel_bo_gpuva(struct panthor_kernel_bo *bo)
 {
-- 
2.48.1

[PATCH v3 2/4] drm/panthor: Add driver IOCTL for setting BO labels

[Adrián Larumbe]

Allow UM to label a BO for which it possesses a DRM handle.

Signed-off-by: Adrián Larumbe <adrian.larumbe@collabora.com>
---
 drivers/gpu/drm/panthor/panthor_drv.c | 40 +++++++++++++++++++++++++++
 include/uapi/drm/panthor_drm.h        | 19 +++++++++++++
 2 files changed, 59 insertions(+)

diff --git a/drivers/gpu/drm/panthor/panthor_drv.c b/drivers/gpu/drm/panthor/panthor_drv.c
index 310bb44abe1a..488d17466494 100644
--- a/drivers/gpu/drm/panthor/panthor_drv.c
+++ b/drivers/gpu/drm/panthor/panthor_drv.c
@@ -1330,6 +1330,44 @@ static int panthor_ioctl_vm_get_state(struct drm_device *ddev, void *data,
 	return 0;
 }
 
+static int panthor_ioctl_bo_set_label(struct drm_device *ddev, void *data,
+				  struct drm_file *file)
+{
+	struct drm_panthor_bo_set_label *args = data;
+	struct drm_gem_object *obj;
+	const char *label;
+	int ret = 0;
+
+	obj = drm_gem_object_lookup(file, args->handle);
+	if (!obj)
+		return -ENOENT;
+
+	if (args->size && args->label) {
+		if (args->size > PAGE_SIZE) {
+			ret = -E2BIG;
+			goto err_label;
+		}
+
+		label = strndup_user(u64_to_user_ptr(args->label), args->size);
+		if (IS_ERR(label)) {
+			ret = PTR_ERR(label);
+			goto err_label;
+		}
+	} else if (args->size && !args->label) {
+		ret = -EINVAL;
+		goto err_label;
+	} else {
+		label = NULL;
+	}
+
+	panthor_gem_bo_set_label(obj, label);
+
+err_label:
+	drm_gem_object_put(obj);
+
+	return ret;
+}
+
 static int
 panthor_open(struct drm_device *ddev, struct drm_file *file)
 {
@@ -1399,6 +1437,7 @@ static const struct drm_ioctl_desc panthor_drm_driver_ioctls[] = {
 	PANTHOR_IOCTL(TILER_HEAP_CREATE, tiler_heap_create, DRM_RENDER_ALLOW),
 	PANTHOR_IOCTL(TILER_HEAP_DESTROY, tiler_heap_destroy, DRM_RENDER_ALLOW),
 	PANTHOR_IOCTL(GROUP_SUBMIT, group_submit, DRM_RENDER_ALLOW),
+	PANTHOR_IOCTL(BO_SET_LABEL, bo_set_label, DRM_RENDER_ALLOW),
 };
 
 static int panthor_mmap(struct file *filp, struct vm_area_struct *vma)
@@ -1508,6 +1547,7 @@ static void panthor_debugfs_init(struct drm_minor *minor)
  * - 1.2 - adds DEV_QUERY_GROUP_PRIORITIES_INFO query
  *       - adds PANTHOR_GROUP_PRIORITY_REALTIME priority
  * - 1.3 - adds DRM_PANTHOR_GROUP_STATE_INNOCENT flag
+ * - 1.4 - adds DRM_IOCTL_PANTHOR_BO_SET_LABEL ioctl
  */
 static const struct drm_driver panthor_drm_driver = {
 	.driver_features = DRIVER_RENDER | DRIVER_GEM | DRIVER_SYNCOBJ |
diff --git a/include/uapi/drm/panthor_drm.h b/include/uapi/drm/panthor_drm.h
index 97e2c4510e69..26b52f147360 100644
--- a/include/uapi/drm/panthor_drm.h
+++ b/include/uapi/drm/panthor_drm.h
@@ -127,6 +127,9 @@ enum drm_panthor_ioctl_id {
 
 	/** @DRM_PANTHOR_TILER_HEAP_DESTROY: Destroy a tiler heap. */
 	DRM_PANTHOR_TILER_HEAP_DESTROY,
+
+	/** @DRM_PANTHOR_BO_SET_LABEL: Label a BO. */
+	DRM_PANTHOR_BO_SET_LABEL,
 };
 
 /**
@@ -977,6 +980,20 @@ struct drm_panthor_tiler_heap_destroy {
 	__u32 pad;
 };
 
+/**
+ * struct drm_panthor_bo_set_label - Arguments passed to DRM_IOCTL_PANTHOR_BO_SET_LABEL
+ */
+struct drm_panthor_bo_set_label {
+	/** @handle: Handle of the buffer object to label. */
+	__u32 handle;
+
+	/** @size: Length of the label, including the NULL terminator. */
+	__u32 size;
+
+	/** @label: User pointer to a NULL-terminated string */
+	__u64 label;
+};
+
 /**
  * DRM_IOCTL_PANTHOR() - Build a Panthor IOCTL number
  * @__access: Access type. Must be R, W or RW.
@@ -1019,6 +1036,8 @@ enum {
 		DRM_IOCTL_PANTHOR(WR, TILER_HEAP_CREATE, tiler_heap_create),
 	DRM_IOCTL_PANTHOR_TILER_HEAP_DESTROY =
 		DRM_IOCTL_PANTHOR(WR, TILER_HEAP_DESTROY, tiler_heap_destroy),
+	DRM_IOCTL_PANTHOR_BO_SET_LABEL =
+		DRM_IOCTL_PANTHOR(WR, BO_SET_LABEL, bo_set_label),
 };
 
 #if defined(__cplusplus)
-- 
2.48.1

[PATCH v3 3/4] drm/panthor: show device-wide list of DRM GEM objects over DebugFS

[Adrián Larumbe]

Add a device DebugFS file that displays a complete list of all the DRM GEM
objects that are exposed to UM through a DRM handle.

Since leaking object identifiers that might belong to a different NS is
inadmissible, this functionality is only made available in debug builds
with DEBUGFS support enabled.

File format is that of a table, with each entry displaying a variety of
fields with information about each GEM object.

Each GEM object entry in the file displays the following information
fields: Client PID, BO's global name, reference count, BO virtual size, BO
resize size, VM address in its DRM-managed range, BO label and a flag
bitmask.

Signed-off-by: Adrián Larumbe <adrian.larumbe@collabora.com>
---
 drivers/gpu/drm/panthor/panthor_device.c |   5 +
 drivers/gpu/drm/panthor/panthor_device.h |  11 ++
 drivers/gpu/drm/panthor/panthor_drv.c    |  26 +++++
 drivers/gpu/drm/panthor/panthor_gem.c    | 130 +++++++++++++++++++++++
 drivers/gpu/drm/panthor/panthor_gem.h    |  29 +++++
 5 files changed, 201 insertions(+)

diff --git a/drivers/gpu/drm/panthor/panthor_device.c b/drivers/gpu/drm/panthor/panthor_device.c
index a9da1d1eeb70..bae1a74d7111 100644
--- a/drivers/gpu/drm/panthor/panthor_device.c
+++ b/drivers/gpu/drm/panthor/panthor_device.c
@@ -263,6 +263,11 @@ int panthor_device_init(struct panthor_device *ptdev)
 	pm_runtime_set_autosuspend_delay(ptdev->base.dev, 50);
 	pm_runtime_use_autosuspend(ptdev->base.dev);
 
+#ifdef CONFIG_DEBUG_FS
+	drmm_mutex_init(&ptdev->base, &ptdev->gems.lock);
+	INIT_LIST_HEAD(&ptdev->gems.node);
+#endif
+
 	ret = drm_dev_register(&ptdev->base, 0);
 	if (ret)
 		goto err_disable_autosuspend;
diff --git a/drivers/gpu/drm/panthor/panthor_device.h b/drivers/gpu/drm/panthor/panthor_device.h
index da6574021664..86206a961b38 100644
--- a/drivers/gpu/drm/panthor/panthor_device.h
+++ b/drivers/gpu/drm/panthor/panthor_device.h
@@ -205,6 +205,17 @@ struct panthor_device {
 
 	/** @fast_rate: Maximum device clock frequency. Set by DVFS */
 	unsigned long fast_rate;
+
+#ifdef CONFIG_DEBUG_FS
+	/** @gems: Device-wide list of GEM objects owned by at least one file. */
+	struct {
+		/** @gems.lock: Protects the device-wide list of GEM objects. */
+		struct mutex lock;
+
+		/** @node: Used to keep track of all the device's DRM objects */
+		struct list_head node;
+	} gems;
+#endif
 };
 
 struct panthor_gpu_usage {
diff --git a/drivers/gpu/drm/panthor/panthor_drv.c b/drivers/gpu/drm/panthor/panthor_drv.c
index 488d17466494..0ba68a51b4ef 100644
--- a/drivers/gpu/drm/panthor/panthor_drv.c
+++ b/drivers/gpu/drm/panthor/panthor_drv.c
@@ -1534,9 +1534,35 @@ static const struct file_operations panthor_drm_driver_fops = {
 };
 
 #ifdef CONFIG_DEBUG_FS
+static int panthor_gems_show(struct seq_file *m, void *data)
+{
+	struct drm_info_node *node = m->private;
+	struct drm_device *dev = node->minor->dev;
+	struct panthor_device *ptdev = container_of(dev, struct panthor_device, base);
+
+	panthor_gem_debugfs_print_bos(ptdev, m);
+
+	return 0;
+}
+
+
+static struct drm_info_list panthor_debugfs_list[] = {
+	{"gems", panthor_gems_show, 0, NULL},
+};
+
+static int panthor_gems_debugfs_init(struct drm_minor *minor)
+{
+	drm_debugfs_create_files(panthor_debugfs_list,
+				 ARRAY_SIZE(panthor_debugfs_list),
+				 minor->debugfs_root, minor);
+
+	return 0;
+}
+
 static void panthor_debugfs_init(struct drm_minor *minor)
 {
 	panthor_mmu_debugfs_init(minor);
+	panthor_gems_debugfs_init(minor);
 }
 #endif
 
diff --git a/drivers/gpu/drm/panthor/panthor_gem.c b/drivers/gpu/drm/panthor/panthor_gem.c
index 7d017f9d1d52..fbf560920194 100644
--- a/drivers/gpu/drm/panthor/panthor_gem.c
+++ b/drivers/gpu/drm/panthor/panthor_gem.c
@@ -2,6 +2,7 @@
 /* Copyright 2019 Linaro, Ltd, Rob Herring <robh@kernel.org> */
 /* Copyright 2023 Collabora ltd. */
 
+#include <linux/cleanup.h>
 #include <linux/dma-buf.h>
 #include <linux/dma-mapping.h>
 #include <linux/err.h>
@@ -13,11 +14,49 @@
 #include "panthor_gem.h"
 #include "panthor_mmu.h"
 
+#ifdef CONFIG_DEBUG_FS
+static void panthor_gem_debugfs_bo_init(struct panthor_gem_object *bo)
+{
+	INIT_LIST_HEAD(&bo->gems.node);
+	bo->gems.creator.tgid = current->group_leader->pid;
+	get_task_comm(bo->gems.creator.process_name, current->group_leader);
+}
+
+static void panthor_gem_debugfs_bo_add(struct panthor_gem_object *bo)
+{
+	struct panthor_device *ptdev =  container_of(bo->base.base.dev,
+						     struct panthor_device, base);
+
+	mutex_lock(&ptdev->gems.lock);
+	list_add_tail(&bo->gems.node, &ptdev->gems.node);
+	mutex_unlock(&ptdev->gems.lock);
+}
+
+static void panthor_gem_debugfs_bo_rm(struct panthor_gem_object *bo)
+{
+	struct panthor_device *ptdev = container_of(bo->base.base.dev,
+						    struct panthor_device, base);
+
+	if (list_empty(&bo->gems.node))
+		return;
+
+	mutex_lock(&ptdev->gems.lock);
+	list_del_init(&bo->gems.node);
+	mutex_unlock(&ptdev->gems.lock);
+}
+#else
+static void panthor_gem_debugfs_bo_init(struct panthor_gem_object *bo) {}
+static void panthor_gem_debugfs_bo_add(struct panthor_gem_object *bo) {}
+static void panthor_gem_debugfs_bo_rm(struct panthor_gem_object *bo) {}
+#endif
+
 static void panthor_gem_free_object(struct drm_gem_object *obj)
 {
 	struct panthor_gem_object *bo = to_panthor_bo(obj);
 	struct drm_gem_object *vm_root_gem = bo->exclusive_vm_root_gem;
 
+	panthor_gem_debugfs_bo_rm(bo);
+
 	/*
 	 * Label might have been allocated with kstrdup_const(),
 	 * we need to take that into account when freeing the memory
@@ -206,6 +245,8 @@ struct drm_gem_object *panthor_gem_create_object(struct drm_device *ddev, size_t
 	drm_gem_gpuva_set_lock(&obj->base.base, &obj->gpuva_list_lock);
 	mutex_init(&obj->label.lock);
 
+	panthor_gem_debugfs_bo_init(obj);
+
 	return &obj->base.base;
 }
 
@@ -254,6 +295,8 @@ panthor_gem_create_with_handle(struct drm_file *file,
 	/* drop reference from allocate - handle holds it now. */
 	drm_gem_object_put(&shmem->base);
 
+	panthor_gem_debugfs_bo_add(bo);
+
 	return ret;
 }
 
@@ -285,3 +328,90 @@ panthor_gem_kernel_bo_set_label(struct panthor_kernel_bo *bo, const char *label)
 
 	panthor_gem_bo_set_label(bo->obj, kstrdup_const(str, GFP_KERNEL));
 }
+
+#ifdef CONFIG_DEBUG_FS
+static bool panfrost_gem_print_flag(const char *name,
+				    bool is_set,
+				    bool other_flags_printed,
+				    struct seq_file *m)
+{
+	if (is_set)
+		seq_printf(m, "%s%s", other_flags_printed ? "," : "", name);
+
+	return is_set | other_flags_printed;
+}
+
+struct gem_size_totals {
+	size_t size;
+	size_t resident;
+	size_t reclaimable;
+};
+
+static void panthor_gem_debugfs_bo_print(struct panthor_gem_object *bo,
+					 struct seq_file *m,
+					 struct gem_size_totals *totals)
+{
+	unsigned int refcount = kref_read(&bo->base.base.refcount);
+	char creator_info[32] = {};
+	bool has_flags = false;
+	size_t resident_size;
+
+	/* Skip BOs being destroyed. */
+	if (!refcount)
+		return;
+
+	resident_size = bo->base.pages != NULL ? bo->base.base.size : 0;
+
+	snprintf(creator_info, sizeof(creator_info),
+		 "%s/%d", bo->gems.creator.process_name, bo->gems.creator.tgid);
+	seq_printf(m, "%-32s%-16d%-16d%-16zd%-16zd%-16lx",
+		   creator_info,
+		   bo->base.base.name,
+		   refcount,
+		   bo->base.base.size,
+		   resident_size,
+		   drm_vma_node_start(&bo->base.base.vma_node));
+
+	seq_puts(m, "(");
+	has_flags = panfrost_gem_print_flag("imported", bo->base.base.import_attach != NULL,
+					    has_flags, m);
+	has_flags = panfrost_gem_print_flag("exported", bo->base.base.dma_buf != NULL,
+					    has_flags, m);
+	if (bo->base.madv < 0)
+		has_flags = panfrost_gem_print_flag("purged", true, has_flags, m);
+	else if (bo->base.madv > 0)
+		has_flags = panfrost_gem_print_flag("purgeable", true, has_flags, m);
+	if (!has_flags)
+		seq_puts(m, "none");
+	seq_puts(m, ")");
+
+	mutex_lock(&bo->label.lock);
+	seq_printf(m, "%-16s%-60s", "", bo->label.str ? : NULL);
+	mutex_unlock(&bo->label.lock);
+	seq_puts(m, "\n");
+
+	totals->size += bo->base.base.size;
+	totals->resident += resident_size;
+	if (bo->base.madv > 0)
+		totals->reclaimable += resident_size;
+}
+
+void panthor_gem_debugfs_print_bos(struct panthor_device *ptdev,
+				   struct seq_file *m)
+{
+	struct gem_size_totals totals = {0};
+	struct panthor_gem_object *bo;
+
+	seq_puts(m, "created-by                      global-name     refcount        size            resident-size   file-offset     flags           label\n");
+	seq_puts(m, "------------------------------------------------------------------------------------------------------------------------------------------------\n");
+
+	scoped_guard(mutex, &ptdev->gems.lock) {
+		list_for_each_entry(bo, &ptdev->gems.node, gems.node)
+			panthor_gem_debugfs_bo_print(bo, m, &totals);
+	}
+
+	seq_puts(m, "================================================================================================================================================\n");
+	seq_printf(m, "Total size: %zd, Total resident: %zd, Total reclaimable: %zd\n",
+		   totals.size, totals.resident, totals.reclaimable);
+}
+#endif
diff --git a/drivers/gpu/drm/panthor/panthor_gem.h b/drivers/gpu/drm/panthor/panthor_gem.h
index 0582826b341a..7c896ec35801 100644
--- a/drivers/gpu/drm/panthor/panthor_gem.h
+++ b/drivers/gpu/drm/panthor/panthor_gem.h
@@ -13,6 +13,26 @@
 
 struct panthor_vm;
 
+/**
+ * struct panthor_gem_debugfs - GEM object's DebugFS list information
+ */
+struct panthor_gem_debugfs {
+	/**
+	 * @node: Node used to insert the object in the device-wide list of
+	 * GEM objects, to display information about it through a DebugFS file.
+	 */
+	struct list_head node;
+
+	/** @creator: Information about the UM process which created the GEM. */
+	struct {
+		/** @creator.process_name: Group leader name in owning thread's process */
+		char process_name[TASK_COMM_LEN];
+
+		/** @creator.tgid: PID of the thread's group leader within its process */
+		pid_t tgid;
+	} creator;
+};
+
 /**
  * struct panthor_gem_object - Driver specific GEM object.
  */
@@ -60,6 +80,10 @@ struct panthor_gem_object {
 		/** @lock.str: Protects access to the @label.str field. */
 		struct mutex lock;
 	} label;
+
+#ifdef CONFIG_DEBUG_FS
+	struct panthor_gem_debugfs gems;
+#endif
 };
 
 /**
@@ -155,4 +179,9 @@ panthor_kernel_bo_create(struct panthor_device *ptdev, struct panthor_vm *vm,
 
 void panthor_kernel_bo_destroy(struct panthor_kernel_bo *bo);
 
+#ifdef CONFIG_DEBUG_FS
+void panthor_gem_debugfs_print_bos(struct panthor_device *pfdev,
+				   struct seq_file *m);
+#endif
+
 #endif /* __PANTHOR_GEM_H__ */
-- 
2.48.1

[PATCH v3 4/4] drm/panthor: Display heap chunk entries in DebugFS GEMS file

[Adrián Larumbe]

Expand the driver's DebugFS GEMS file to display entries for the heap
chunks' GEM objects, both those allocated at heap creation time through an
ioctl(), or in response to a tiler OOM event.

Signed-off-by: Adrián Larumbe <adrian.larumbe@collabora.com>
---
 drivers/gpu/drm/panthor/panthor_gem.c  | 12 +-----------
 drivers/gpu/drm/panthor/panthor_gem.h  | 14 ++++++++++++++
 drivers/gpu/drm/panthor/panthor_heap.c |  3 +++
 3 files changed, 18 insertions(+), 11 deletions(-)

diff --git a/drivers/gpu/drm/panthor/panthor_gem.c b/drivers/gpu/drm/panthor/panthor_gem.c
index fbf560920194..efc14c179680 100644
--- a/drivers/gpu/drm/panthor/panthor_gem.c
+++ b/drivers/gpu/drm/panthor/panthor_gem.c
@@ -22,16 +22,6 @@ static void panthor_gem_debugfs_bo_init(struct panthor_gem_object *bo)
 	get_task_comm(bo->gems.creator.process_name, current->group_leader);
 }
 
-static void panthor_gem_debugfs_bo_add(struct panthor_gem_object *bo)
-{
-	struct panthor_device *ptdev =  container_of(bo->base.base.dev,
-						     struct panthor_device, base);
-
-	mutex_lock(&ptdev->gems.lock);
-	list_add_tail(&bo->gems.node, &ptdev->gems.node);
-	mutex_unlock(&ptdev->gems.lock);
-}
-
 static void panthor_gem_debugfs_bo_rm(struct panthor_gem_object *bo)
 {
 	struct panthor_device *ptdev = container_of(bo->base.base.dev,
@@ -44,9 +34,9 @@ static void panthor_gem_debugfs_bo_rm(struct panthor_gem_object *bo)
 	list_del_init(&bo->gems.node);
 	mutex_unlock(&ptdev->gems.lock);
 }
+
 #else
 static void panthor_gem_debugfs_bo_init(struct panthor_gem_object *bo) {}
-static void panthor_gem_debugfs_bo_add(struct panthor_gem_object *bo) {}
 static void panthor_gem_debugfs_bo_rm(struct panthor_gem_object *bo) {}
 #endif
 
diff --git a/drivers/gpu/drm/panthor/panthor_gem.h b/drivers/gpu/drm/panthor/panthor_gem.h
index 7c896ec35801..95093b98b990 100644
--- a/drivers/gpu/drm/panthor/panthor_gem.h
+++ b/drivers/gpu/drm/panthor/panthor_gem.h
@@ -11,6 +11,8 @@
 #include <linux/iosys-map.h>
 #include <linux/rwsem.h>
 
+#include "panthor_device.h"
+
 struct panthor_vm;
 
 /**
@@ -182,6 +184,18 @@ void panthor_kernel_bo_destroy(struct panthor_kernel_bo *bo);
 #ifdef CONFIG_DEBUG_FS
 void panthor_gem_debugfs_print_bos(struct panthor_device *pfdev,
 				   struct seq_file *m);
+
+static inline void panthor_gem_debugfs_bo_add(struct panthor_gem_object *bo)
+{
+	struct panthor_device *ptdev =  container_of(bo->base.base.dev,
+						     struct panthor_device, base);
+
+	mutex_lock(&ptdev->gems.lock);
+	list_add_tail(&bo->gems.node, &ptdev->gems.node);
+	mutex_unlock(&ptdev->gems.lock);
+}
+#elif
+static inline void panthor_gem_debugfs_bo_add(struct panthor_gem_object *bo) {}
 #endif
 
 #endif /* __PANTHOR_GEM_H__ */
diff --git a/drivers/gpu/drm/panthor/panthor_heap.c b/drivers/gpu/drm/panthor/panthor_heap.c
index db0285ce5812..30136b386869 100644
--- a/drivers/gpu/drm/panthor/panthor_heap.c
+++ b/drivers/gpu/drm/panthor/panthor_heap.c
@@ -180,6 +180,9 @@ static int panthor_alloc_heap_chunk(struct panthor_device *ptdev,
 	heap->chunk_count++;
 	mutex_unlock(&heap->lock);
 
+	panthor_gem_kernel_bo_set_label(chunk->bo, "Tiler heap chunk");
+	panthor_gem_debugfs_bo_add(to_panthor_bo(chunk->bo->obj));
+
 	return 0;
 
 err_destroy_bo:
-- 
2.48.1

Re: [PATCH v3 3/4] drm/panthor: show device-wide list of DRM GEM objects over DebugFS

[Boris Brezillon]

On Thu, 27 Mar 2025 14:08:36 +0000
Adrián Larumbe <adrian.larumbe@collabora.com> wrote:

> Add a device DebugFS file that displays a complete list of all the DRM GEM
> objects that are exposed to UM through a DRM handle.
> 
> Since leaking object identifiers that might belong to a different NS is
> inadmissible, this functionality is only made available in debug builds
> with DEBUGFS support enabled.
> 
> File format is that of a table, with each entry displaying a variety of
> fields with information about each GEM object.
> 
> Each GEM object entry in the file displays the following information
> fields: Client PID, BO's global name, reference count, BO virtual size, BO
> resize size, VM address in its DRM-managed range, BO label and a flag
> bitmask.
> 
> Signed-off-by: Adrián Larumbe <adrian.larumbe@collabora.com>
> ---
>  drivers/gpu/drm/panthor/panthor_device.c |   5 +
>  drivers/gpu/drm/panthor/panthor_device.h |  11 ++
>  drivers/gpu/drm/panthor/panthor_drv.c    |  26 +++++
>  drivers/gpu/drm/panthor/panthor_gem.c    | 130 +++++++++++++++++++++++
>  drivers/gpu/drm/panthor/panthor_gem.h    |  29 +++++
>  5 files changed, 201 insertions(+)
> 
> diff --git a/drivers/gpu/drm/panthor/panthor_device.c b/drivers/gpu/drm/panthor/panthor_device.c
> index a9da1d1eeb70..bae1a74d7111 100644
> --- a/drivers/gpu/drm/panthor/panthor_device.c
> +++ b/drivers/gpu/drm/panthor/panthor_device.c
> @@ -263,6 +263,11 @@ int panthor_device_init(struct panthor_device *ptdev)
>  	pm_runtime_set_autosuspend_delay(ptdev->base.dev, 50);
>  	pm_runtime_use_autosuspend(ptdev->base.dev);
>  
> +#ifdef CONFIG_DEBUG_FS
> +	drmm_mutex_init(&ptdev->base, &ptdev->gems.lock);
> +	INIT_LIST_HEAD(&ptdev->gems.node);
> +#endif
> +
>  	ret = drm_dev_register(&ptdev->base, 0);
>  	if (ret)
>  		goto err_disable_autosuspend;
> diff --git a/drivers/gpu/drm/panthor/panthor_device.h b/drivers/gpu/drm/panthor/panthor_device.h
> index da6574021664..86206a961b38 100644
> --- a/drivers/gpu/drm/panthor/panthor_device.h
> +++ b/drivers/gpu/drm/panthor/panthor_device.h
> @@ -205,6 +205,17 @@ struct panthor_device {
>  
>  	/** @fast_rate: Maximum device clock frequency. Set by DVFS */
>  	unsigned long fast_rate;
> +
> +#ifdef CONFIG_DEBUG_FS
> +	/** @gems: Device-wide list of GEM objects owned by at least one file. */
> +	struct {
> +		/** @gems.lock: Protects the device-wide list of GEM objects. */
> +		struct mutex lock;
> +
> +		/** @node: Used to keep track of all the device's DRM objects */
> +		struct list_head node;
> +	} gems;
> +#endif
>  };
>  
>  struct panthor_gpu_usage {
> diff --git a/drivers/gpu/drm/panthor/panthor_drv.c b/drivers/gpu/drm/panthor/panthor_drv.c
> index 488d17466494..0ba68a51b4ef 100644
> --- a/drivers/gpu/drm/panthor/panthor_drv.c
> +++ b/drivers/gpu/drm/panthor/panthor_drv.c
> @@ -1534,9 +1534,35 @@ static const struct file_operations panthor_drm_driver_fops = {
>  };
>  
>  #ifdef CONFIG_DEBUG_FS
> +static int panthor_gems_show(struct seq_file *m, void *data)
> +{
> +	struct drm_info_node *node = m->private;
> +	struct drm_device *dev = node->minor->dev;
> +	struct panthor_device *ptdev = container_of(dev, struct panthor_device, base);
> +
> +	panthor_gem_debugfs_print_bos(ptdev, m);
> +
> +	return 0;
> +}
> +
> +
> +static struct drm_info_list panthor_debugfs_list[] = {
> +	{"gems", panthor_gems_show, 0, NULL},
> +};
> +
> +static int panthor_gems_debugfs_init(struct drm_minor *minor)
> +{
> +	drm_debugfs_create_files(panthor_debugfs_list,
> +				 ARRAY_SIZE(panthor_debugfs_list),
> +				 minor->debugfs_root, minor);
> +
> +	return 0;
> +}
> +
>  static void panthor_debugfs_init(struct drm_minor *minor)
>  {
>  	panthor_mmu_debugfs_init(minor);
> +	panthor_gems_debugfs_init(minor);
>  }
>  #endif
>  
> diff --git a/drivers/gpu/drm/panthor/panthor_gem.c b/drivers/gpu/drm/panthor/panthor_gem.c
> index 7d017f9d1d52..fbf560920194 100644
> --- a/drivers/gpu/drm/panthor/panthor_gem.c
> +++ b/drivers/gpu/drm/panthor/panthor_gem.c
> @@ -2,6 +2,7 @@
>  /* Copyright 2019 Linaro, Ltd, Rob Herring <robh@kernel.org> */
>  /* Copyright 2023 Collabora ltd. */
>  
> +#include <linux/cleanup.h>
>  #include <linux/dma-buf.h>
>  #include <linux/dma-mapping.h>
>  #include <linux/err.h>
> @@ -13,11 +14,49 @@
>  #include "panthor_gem.h"
>  #include "panthor_mmu.h"
>  
> +#ifdef CONFIG_DEBUG_FS
> +static void panthor_gem_debugfs_bo_init(struct panthor_gem_object *bo)
> +{
> +	INIT_LIST_HEAD(&bo->gems.node);
> +	bo->gems.creator.tgid = current->group_leader->pid;
> +	get_task_comm(bo->gems.creator.process_name, current->group_leader);
> +}
> +
> +static void panthor_gem_debugfs_bo_add(struct panthor_gem_object *bo)
> +{
> +	struct panthor_device *ptdev =  container_of(bo->base.base.dev,
> +						     struct panthor_device, base);
> +
> +	mutex_lock(&ptdev->gems.lock);
> +	list_add_tail(&bo->gems.node, &ptdev->gems.node);
> +	mutex_unlock(&ptdev->gems.lock);
> +}
> +
> +static void panthor_gem_debugfs_bo_rm(struct panthor_gem_object *bo)
> +{
> +	struct panthor_device *ptdev = container_of(bo->base.base.dev,
> +						    struct panthor_device, base);
> +
> +	if (list_empty(&bo->gems.node))
> +		return;
> +
> +	mutex_lock(&ptdev->gems.lock);
> +	list_del_init(&bo->gems.node);
> +	mutex_unlock(&ptdev->gems.lock);
> +}
> +#else
> +static void panthor_gem_debugfs_bo_init(struct panthor_gem_object *bo) {}
> +static void panthor_gem_debugfs_bo_add(struct panthor_gem_object *bo) {}
> +static void panthor_gem_debugfs_bo_rm(struct panthor_gem_object *bo) {}
> +#endif
> +
>  static void panthor_gem_free_object(struct drm_gem_object *obj)
>  {
>  	struct panthor_gem_object *bo = to_panthor_bo(obj);
>  	struct drm_gem_object *vm_root_gem = bo->exclusive_vm_root_gem;
>  
> +	panthor_gem_debugfs_bo_rm(bo);
> +
>  	/*
>  	 * Label might have been allocated with kstrdup_const(),
>  	 * we need to take that into account when freeing the memory
> @@ -206,6 +245,8 @@ struct drm_gem_object *panthor_gem_create_object(struct drm_device *ddev, size_t
>  	drm_gem_gpuva_set_lock(&obj->base.base, &obj->gpuva_list_lock);
>  	mutex_init(&obj->label.lock);
>  
> +	panthor_gem_debugfs_bo_init(obj);
> +
>  	return &obj->base.base;
>  }
>  
> @@ -254,6 +295,8 @@ panthor_gem_create_with_handle(struct drm_file *file,
>  	/* drop reference from allocate - handle holds it now. */
>  	drm_gem_object_put(&shmem->base);
>  
> +	panthor_gem_debugfs_bo_add(bo);

As mentioned in the other thread, I'd be tempted to:

- merge panthor_gem_debugfs_bo_init() into panthor_gem_debugfs_bo_add()
- call panthor_gem_debugfs_bo_add() from panthor_gem_create_object()
- have a way to differentiates kernel and user BOs.

> +
>  	return ret;
>  }
>  
> @@ -285,3 +328,90 @@ panthor_gem_kernel_bo_set_label(struct panthor_kernel_bo *bo, const char *label)
>  
>  	panthor_gem_bo_set_label(bo->obj, kstrdup_const(str, GFP_KERNEL));
>  }
> +
> +#ifdef CONFIG_DEBUG_FS
> +static bool panfrost_gem_print_flag(const char *name,
> +				    bool is_set,
> +				    bool other_flags_printed,
> +				    struct seq_file *m)
> +{
> +	if (is_set)
> +		seq_printf(m, "%s%s", other_flags_printed ? "," : "", name);
> +
> +	return is_set | other_flags_printed;
> +}
> +
> +struct gem_size_totals {
> +	size_t size;
> +	size_t resident;
> +	size_t reclaimable;
> +};
> +
> +static void panthor_gem_debugfs_bo_print(struct panthor_gem_object *bo,
> +					 struct seq_file *m,
> +					 struct gem_size_totals *totals)
> +{
> +	unsigned int refcount = kref_read(&bo->base.base.refcount);
> +	char creator_info[32] = {};
> +	bool has_flags = false;
> +	size_t resident_size;
> +
> +	/* Skip BOs being destroyed. */
> +	if (!refcount)
> +		return;
> +
> +	resident_size = bo->base.pages != NULL ? bo->base.base.size : 0;
> +
> +	snprintf(creator_info, sizeof(creator_info),
> +		 "%s/%d", bo->gems.creator.process_name, bo->gems.creator.tgid);
> +	seq_printf(m, "%-32s%-16d%-16d%-16zd%-16zd%-16lx",
> +		   creator_info,
> +		   bo->base.base.name,
> +		   refcount,
> +		   bo->base.base.size,
> +		   resident_size,
> +		   drm_vma_node_start(&bo->base.base.vma_node));
> +
> +	seq_puts(m, "(");
> +	has_flags = panfrost_gem_print_flag("imported", bo->base.base.import_attach != NULL,
> +					    has_flags, m);
> +	has_flags = panfrost_gem_print_flag("exported", bo->base.base.dma_buf != NULL,
> +					    has_flags, m);
> +	if (bo->base.madv < 0)
> +		has_flags = panfrost_gem_print_flag("purged", true, has_flags, m);
> +	else if (bo->base.madv > 0)
> +		has_flags = panfrost_gem_print_flag("purgeable", true, has_flags, m);
> +	if (!has_flags)
> +		seq_puts(m, "none");
> +	seq_puts(m, ")");
> +
> +	mutex_lock(&bo->label.lock);
> +	seq_printf(m, "%-16s%-60s", "", bo->label.str ? : NULL);
> +	mutex_unlock(&bo->label.lock);
> +	seq_puts(m, "\n");
> +
> +	totals->size += bo->base.base.size;
> +	totals->resident += resident_size;
> +	if (bo->base.madv > 0)
> +		totals->reclaimable += resident_size;
> +}
> +
> +void panthor_gem_debugfs_print_bos(struct panthor_device *ptdev,
> +				   struct seq_file *m)
> +{
> +	struct gem_size_totals totals = {0};
> +	struct panthor_gem_object *bo;
> +
> +	seq_puts(m, "created-by                      global-name     refcount        size            resident-size   file-offset     flags           label\n");
> +	seq_puts(m, "------------------------------------------------------------------------------------------------------------------------------------------------\n");
> +
> +	scoped_guard(mutex, &ptdev->gems.lock) {
> +		list_for_each_entry(bo, &ptdev->gems.node, gems.node)
> +			panthor_gem_debugfs_bo_print(bo, m, &totals);
> +	}
> +
> +	seq_puts(m, "================================================================================================================================================\n");
> +	seq_printf(m, "Total size: %zd, Total resident: %zd, Total reclaimable: %zd\n",
> +		   totals.size, totals.resident, totals.reclaimable);
> +}
> +#endif
> diff --git a/drivers/gpu/drm/panthor/panthor_gem.h b/drivers/gpu/drm/panthor/panthor_gem.h
> index 0582826b341a..7c896ec35801 100644
> --- a/drivers/gpu/drm/panthor/panthor_gem.h
> +++ b/drivers/gpu/drm/panthor/panthor_gem.h
> @@ -13,6 +13,26 @@
>  
>  struct panthor_vm;
>  
> +/**
> + * struct panthor_gem_debugfs - GEM object's DebugFS list information
> + */
> +struct panthor_gem_debugfs {
> +	/**
> +	 * @node: Node used to insert the object in the device-wide list of
> +	 * GEM objects, to display information about it through a DebugFS file.
> +	 */
> +	struct list_head node;
> +
> +	/** @creator: Information about the UM process which created the GEM. */
> +	struct {
> +		/** @creator.process_name: Group leader name in owning thread's process */
> +		char process_name[TASK_COMM_LEN];
> +
> +		/** @creator.tgid: PID of the thread's group leader within its process */
> +		pid_t tgid;
> +	} creator;

Add a

	bool kernel_only;

to reflect the fact the BO can't be accessed by the UMD.

> +};
> +
>  /**
>   * struct panthor_gem_object - Driver specific GEM object.
>   */
> @@ -60,6 +80,10 @@ struct panthor_gem_object {
>  		/** @lock.str: Protects access to the @label.str field. */
>  		struct mutex lock;
>  	} label;
> +
> +#ifdef CONFIG_DEBUG_FS
> +	struct panthor_gem_debugfs gems;

s/gems/debugfs/

> +#endif
>  };
>  
>  /**
> @@ -155,4 +179,9 @@ panthor_kernel_bo_create(struct panthor_device *ptdev, struct panthor_vm *vm,
>  
>  void panthor_kernel_bo_destroy(struct panthor_kernel_bo *bo);
>  
> +#ifdef CONFIG_DEBUG_FS
> +void panthor_gem_debugfs_print_bos(struct panthor_device *pfdev,
> +				   struct seq_file *m);
> +#endif
> +
>  #endif /* __PANTHOR_GEM_H__ */

Re: [PATCH v3 3/4] drm/panthor: show device-wide list of DRM GEM objects over DebugFS

[Adrián Larumbe]

Hi Boris,

On 28.03.2025 15:30, Boris Brezillon wrote:
> On Thu, 27 Mar 2025 14:08:36 +0000
> Adrián Larumbe <adrian.larumbe@collabora.com> wrote:
>
> > Add a device DebugFS file that displays a complete list of all the DRM GEM
> > objects that are exposed to UM through a DRM handle.
> >
> > Since leaking object identifiers that might belong to a different NS is
> > inadmissible, this functionality is only made available in debug builds
> > with DEBUGFS support enabled.
> >
> > File format is that of a table, with each entry displaying a variety of
> > fields with information about each GEM object.
> >
> > Each GEM object entry in the file displays the following information
> > fields: Client PID, BO's global name, reference count, BO virtual size, BO
> > resize size, VM address in its DRM-managed range, BO label and a flag
> > bitmask.
> >
> > Signed-off-by: Adrián Larumbe <adrian.larumbe@collabora.com>
> > ---
> >  drivers/gpu/drm/panthor/panthor_device.c |   5 +
> >  drivers/gpu/drm/panthor/panthor_device.h |  11 ++
> >  drivers/gpu/drm/panthor/panthor_drv.c    |  26 +++++
> >  drivers/gpu/drm/panthor/panthor_gem.c    | 130 +++++++++++++++++++++++
> >  drivers/gpu/drm/panthor/panthor_gem.h    |  29 +++++
> >  5 files changed, 201 insertions(+)
> >
> > diff --git a/drivers/gpu/drm/panthor/panthor_device.c b/drivers/gpu/drm/panthor/panthor_device.c
> > index a9da1d1eeb70..bae1a74d7111 100644
> > --- a/drivers/gpu/drm/panthor/panthor_device.c
> > +++ b/drivers/gpu/drm/panthor/panthor_device.c
> > @@ -263,6 +263,11 @@ int panthor_device_init(struct panthor_device *ptdev)
> >  	pm_runtime_set_autosuspend_delay(ptdev->base.dev, 50);
> >  	pm_runtime_use_autosuspend(ptdev->base.dev);
> >
> > +#ifdef CONFIG_DEBUG_FS
> > +	drmm_mutex_init(&ptdev->base, &ptdev->gems.lock);
> > +	INIT_LIST_HEAD(&ptdev->gems.node);
> > +#endif
> > +
> >  	ret = drm_dev_register(&ptdev->base, 0);
> >  	if (ret)
> >  		goto err_disable_autosuspend;
> > diff --git a/drivers/gpu/drm/panthor/panthor_device.h b/drivers/gpu/drm/panthor/panthor_device.h
> > index da6574021664..86206a961b38 100644
> > --- a/drivers/gpu/drm/panthor/panthor_device.h
> > +++ b/drivers/gpu/drm/panthor/panthor_device.h
> > @@ -205,6 +205,17 @@ struct panthor_device {
> >
> >  	/** @fast_rate: Maximum device clock frequency. Set by DVFS */
> >  	unsigned long fast_rate;
> > +
> > +#ifdef CONFIG_DEBUG_FS
> > +	/** @gems: Device-wide list of GEM objects owned by at least one file. */
> > +	struct {
> > +		/** @gems.lock: Protects the device-wide list of GEM objects. */
> > +		struct mutex lock;
> > +
> > +		/** @node: Used to keep track of all the device's DRM objects */
> > +		struct list_head node;
> > +	} gems;
> > +#endif
> >  };
> >
> >  struct panthor_gpu_usage {
> > diff --git a/drivers/gpu/drm/panthor/panthor_drv.c b/drivers/gpu/drm/panthor/panthor_drv.c
> > index 488d17466494..0ba68a51b4ef 100644
> > --- a/drivers/gpu/drm/panthor/panthor_drv.c
> > +++ b/drivers/gpu/drm/panthor/panthor_drv.c
> > @@ -1534,9 +1534,35 @@ static const struct file_operations panthor_drm_driver_fops = {
> >  };
> >
> >  #ifdef CONFIG_DEBUG_FS
> > +static int panthor_gems_show(struct seq_file *m, void *data)
> > +{
> > +	struct drm_info_node *node = m->private;
> > +	struct drm_device *dev = node->minor->dev;
> > +	struct panthor_device *ptdev = container_of(dev, struct panthor_device, base);
> > +
> > +	panthor_gem_debugfs_print_bos(ptdev, m);
> > +
> > +	return 0;
> > +}
> > +
> > +
> > +static struct drm_info_list panthor_debugfs_list[] = {
> > +	{"gems", panthor_gems_show, 0, NULL},
> > +};
> > +
> > +static int panthor_gems_debugfs_init(struct drm_minor *minor)
> > +{
> > +	drm_debugfs_create_files(panthor_debugfs_list,
> > +				 ARRAY_SIZE(panthor_debugfs_list),
> > +				 minor->debugfs_root, minor);
> > +
> > +	return 0;
> > +}
> > +
> >  static void panthor_debugfs_init(struct drm_minor *minor)
> >  {
> >  	panthor_mmu_debugfs_init(minor);
> > +	panthor_gems_debugfs_init(minor);
> >  }
> >  #endif
> >
> > diff --git a/drivers/gpu/drm/panthor/panthor_gem.c b/drivers/gpu/drm/panthor/panthor_gem.c
> > index 7d017f9d1d52..fbf560920194 100644
> > --- a/drivers/gpu/drm/panthor/panthor_gem.c
> > +++ b/drivers/gpu/drm/panthor/panthor_gem.c
> > @@ -2,6 +2,7 @@
> >  /* Copyright 2019 Linaro, Ltd, Rob Herring <robh@kernel.org> */
> >  /* Copyright 2023 Collabora ltd. */
> >
> > +#include <linux/cleanup.h>
> >  #include <linux/dma-buf.h>
> >  #include <linux/dma-mapping.h>
> >  #include <linux/err.h>
> > @@ -13,11 +14,49 @@
> >  #include "panthor_gem.h"
> >  #include "panthor_mmu.h"
> >
> > +#ifdef CONFIG_DEBUG_FS
> > +static void panthor_gem_debugfs_bo_init(struct panthor_gem_object *bo)
> > +{
> > +	INIT_LIST_HEAD(&bo->gems.node);
> > +	bo->gems.creator.tgid = current->group_leader->pid;
> > +	get_task_comm(bo->gems.creator.process_name, current->group_leader);
> > +}
> > +
> > +static void panthor_gem_debugfs_bo_add(struct panthor_gem_object *bo)
> > +{
> > +	struct panthor_device *ptdev =  container_of(bo->base.base.dev,
> > +						     struct panthor_device, base);
> > +
> > +	mutex_lock(&ptdev->gems.lock);
> > +	list_add_tail(&bo->gems.node, &ptdev->gems.node);
> > +	mutex_unlock(&ptdev->gems.lock);
> > +}
> > +
> > +static void panthor_gem_debugfs_bo_rm(struct panthor_gem_object *bo)
> > +{
> > +	struct panthor_device *ptdev = container_of(bo->base.base.dev,
> > +						    struct panthor_device, base);
> > +
> > +	if (list_empty(&bo->gems.node))
> > +		return;
> > +
> > +	mutex_lock(&ptdev->gems.lock);
> > +	list_del_init(&bo->gems.node);
> > +	mutex_unlock(&ptdev->gems.lock);
> > +}
> > +#else
> > +static void panthor_gem_debugfs_bo_init(struct panthor_gem_object *bo) {}
> > +static void panthor_gem_debugfs_bo_add(struct panthor_gem_object *bo) {}
> > +static void panthor_gem_debugfs_bo_rm(struct panthor_gem_object *bo) {}
> > +#endif
> > +
> >  static void panthor_gem_free_object(struct drm_gem_object *obj)
> >  {
> >  	struct panthor_gem_object *bo = to_panthor_bo(obj);
> >  	struct drm_gem_object *vm_root_gem = bo->exclusive_vm_root_gem;
> >
> > +	panthor_gem_debugfs_bo_rm(bo);
> > +
> >  	/*
> >  	 * Label might have been allocated with kstrdup_const(),
> >  	 * we need to take that into account when freeing the memory
> > @@ -206,6 +245,8 @@ struct drm_gem_object *panthor_gem_create_object(struct drm_device *ddev, size_t
> >  	drm_gem_gpuva_set_lock(&obj->base.base, &obj->gpuva_list_lock);
> >  	mutex_init(&obj->label.lock);
> >
> > +	panthor_gem_debugfs_bo_init(obj);
> > +
> >  	return &obj->base.base;
> >  }
> >
> > @@ -254,6 +295,8 @@ panthor_gem_create_with_handle(struct drm_file *file,
> >  	/* drop reference from allocate - handle holds it now. */
> >  	drm_gem_object_put(&shmem->base);
> >
> > +	panthor_gem_debugfs_bo_add(bo);
>
> As mentioned in the other thread, I'd be tempted to:
>
> - merge panthor_gem_debugfs_bo_init() into panthor_gem_debugfs_bo_add()
 - call panthor_gem_debugfs_bo_add() from panthor_gem_create_object()

I did this at first, but then realised it would make it harder to pass a
bo_type mask to the add function to be able to tell kernel or FW-bound
BO's apart from UM or GPU ones, because this would be decided by the
code path in which they're created.

> - have a way to differentiates kernel and user BOs.
>
> > +
> >  	return ret;
> >  }
> >
> > @@ -285,3 +328,90 @@ panthor_gem_kernel_bo_set_label(struct panthor_kernel_bo *bo, const char *label)
> >
> >  	panthor_gem_bo_set_label(bo->obj, kstrdup_const(str, GFP_KERNEL));
> >  }
> > +
> > +#ifdef CONFIG_DEBUG_FS
> > +static bool panfrost_gem_print_flag(const char *name,
> > +				    bool is_set,
> > +				    bool other_flags_printed,
> > +				    struct seq_file *m)
> > +{
> > +	if (is_set)
> > +		seq_printf(m, "%s%s", other_flags_printed ? "," : "", name);
> > +
> > +	return is_set | other_flags_printed;
> > +}
> > +
> > +struct gem_size_totals {
> > +	size_t size;
> > +	size_t resident;
> > +	size_t reclaimable;
> > +};
> > +
> > +static void panthor_gem_debugfs_bo_print(struct panthor_gem_object *bo,
> > +					 struct seq_file *m,
> > +					 struct gem_size_totals *totals)
> > +{
> > +	unsigned int refcount = kref_read(&bo->base.base.refcount);
> > +	char creator_info[32] = {};
> > +	bool has_flags = false;
> > +	size_t resident_size;
> > +
> > +	/* Skip BOs being destroyed. */
> > +	if (!refcount)
> > +		return;
> > +
> > +	resident_size = bo->base.pages != NULL ? bo->base.base.size : 0;
> > +
> > +	snprintf(creator_info, sizeof(creator_info),
> > +		 "%s/%d", bo->gems.creator.process_name, bo->gems.creator.tgid);
> > +	seq_printf(m, "%-32s%-16d%-16d%-16zd%-16zd%-16lx",
> > +		   creator_info,
> > +		   bo->base.base.name,
> > +		   refcount,
> > +		   bo->base.base.size,
> > +		   resident_size,
> > +		   drm_vma_node_start(&bo->base.base.vma_node));
> > +
> > +	seq_puts(m, "(");
> > +	has_flags = panfrost_gem_print_flag("imported", bo->base.base.import_attach != NULL,
> > +					    has_flags, m);
> > +	has_flags = panfrost_gem_print_flag("exported", bo->base.base.dma_buf != NULL,
> > +					    has_flags, m);
> > +	if (bo->base.madv < 0)
> > +		has_flags = panfrost_gem_print_flag("purged", true, has_flags, m);
> > +	else if (bo->base.madv > 0)
> > +		has_flags = panfrost_gem_print_flag("purgeable", true, has_flags, m);
> > +	if (!has_flags)
> > +		seq_puts(m, "none");
> > +	seq_puts(m, ")");
> > +
> > +	mutex_lock(&bo->label.lock);
> > +	seq_printf(m, "%-16s%-60s", "", bo->label.str ? : NULL);
> > +	mutex_unlock(&bo->label.lock);
> > +	seq_puts(m, "\n");
> > +
> > +	totals->size += bo->base.base.size;
> > +	totals->resident += resident_size;
> > +	if (bo->base.madv > 0)
> > +		totals->reclaimable += resident_size;
> > +}
> > +
> > +void panthor_gem_debugfs_print_bos(struct panthor_device *ptdev,
> > +				   struct seq_file *m)
> > +{
> > +	struct gem_size_totals totals = {0};
> > +	struct panthor_gem_object *bo;
> > +
> > +	seq_puts(m, "created-by                      global-name     refcount        size            resident-size   file-offset     flags           label\n");
> > +	seq_puts(m, "------------------------------------------------------------------------------------------------------------------------------------------------\n");
> > +
> > +	scoped_guard(mutex, &ptdev->gems.lock) {
> > +		list_for_each_entry(bo, &ptdev->gems.node, gems.node)
> > +			panthor_gem_debugfs_bo_print(bo, m, &totals);
> > +	}
> > +
> > +	seq_puts(m, "================================================================================================================================================\n");
> > +	seq_printf(m, "Total size: %zd, Total resident: %zd, Total reclaimable: %zd\n",
> > +		   totals.size, totals.resident, totals.reclaimable);
> > +}
> > +#endif
> > diff --git a/drivers/gpu/drm/panthor/panthor_gem.h b/drivers/gpu/drm/panthor/panthor_gem.h
> > index 0582826b341a..7c896ec35801 100644
> > --- a/drivers/gpu/drm/panthor/panthor_gem.h
> > +++ b/drivers/gpu/drm/panthor/panthor_gem.h
> > @@ -13,6 +13,26 @@
> >
> >  struct panthor_vm;
> >
> > +/**
> > + * struct panthor_gem_debugfs - GEM object's DebugFS list information
> > + */
> > +struct panthor_gem_debugfs {
> > +	/**
> > +	 * @node: Node used to insert the object in the device-wide list of
> > +	 * GEM objects, to display information about it through a DebugFS file.
> > +	 */
> > +	struct list_head node;
> > +
> > +	/** @creator: Information about the UM process which created the GEM. */
> > +	struct {
> > +		/** @creator.process_name: Group leader name in owning thread's process */
> > +		char process_name[TASK_COMM_LEN];
> > +
> > +		/** @creator.tgid: PID of the thread's group leader within its process */
> > +		pid_t tgid;
> > +	} creator;
>
> Add a
>
> 	bool kernel_only;
>
> to reflect the fact the BO can't be accessed by the UMD.
>
> > +};
> > +
> >  /**
> >   * struct panthor_gem_object - Driver specific GEM object.
> >   */
> > @@ -60,6 +80,10 @@ struct panthor_gem_object {
> >  		/** @lock.str: Protects access to the @label.str field. */
> >  		struct mutex lock;
> >  	} label;
> > +
> > +#ifdef CONFIG_DEBUG_FS
> > +	struct panthor_gem_debugfs gems;
>
> s/gems/debugfs/
>
> > +#endif
> >  };
> >
> >  /**
> > @@ -155,4 +179,9 @@ panthor_kernel_bo_create(struct panthor_device *ptdev, struct panthor_vm *vm,
> >
> >  void panthor_kernel_bo_destroy(struct panthor_kernel_bo *bo);
> >
> > +#ifdef CONFIG_DEBUG_FS
> > +void panthor_gem_debugfs_print_bos(struct panthor_device *pfdev,
> > +				   struct seq_file *m);
> > +#endif
> > +
> >  #endif /* __PANTHOR_GEM_H__ */

Adrian Larumbe