[PATCH V1] accel/amdxdna: Expose per-client BO memory usage via fdinfo

[Lizhi Hou <lizhi.hou@amd.com>]

Implement amdxdna_show_fdinfo() to report per-client memory usage,
including below driver-specific memory stat:
  - heap allocation (amdxdna-heap-alloc)
  - internal BO allocation (amdxdna-internal-alloc)
  - external BO allocation (amdxdna-external-alloc)

Hook the implementation into the DRM fdinfo infrastructure via
drm_driver.show_fdinfo, while continuing to expose standard DRM
memory stat through drm_show_memory_stats().

This improves observability of per-process memory usage and aligns
with existing fdinfo reporting mechanisms used by other drivers.

Signed-off-by: Max Zhen <max.zhen@amd.com>
Signed-off-by: Lizhi Hou <lizhi.hou@amd.com>
---
 Documentation/accel/amdxdna/amdnpu.rst  | 25 +++++++++++++++++++
 Documentation/gpu/drm-usage-stats.rst   |  1 +
 drivers/accel/amdxdna/amdxdna_pci_drv.c | 32 ++++++++++++++++++++++++-
 3 files changed, 57 insertions(+), 1 deletion(-)

diff --git a/Documentation/accel/amdxdna/amdnpu.rst b/Documentation/accel/amdxdna/amdnpu.rst
index 42e54904f9a8..064973bf4893 100644
--- a/Documentation/accel/amdxdna/amdnpu.rst
+++ b/Documentation/accel/amdxdna/amdnpu.rst
@@ -270,6 +270,31 @@ MERT can report various kinds of telemetry information like the following:
 * Deep Sleep counter
 * etc.
 
+.. _amdxdna-usage-stats:
+
+Amdxdna DRM client usage stats implementation
+=============================================
+
+The amdxdna driver implements the DRM client usage stats specification as
+documented in :ref:`drm-client-usage-stats`.
+
+Example of the output showing the implemented key value pairs:
+
+::
+
+        pos:	0
+        flags:	0100002
+        mnt_id:	29
+        ino:	939
+        drm-driver:	amdxdna_accel_driver
+        drm-client-id:	3219
+        drm-pdev:	0000:c5:00.1
+        amdxdna_accel_driver-heap-alloc:	60 KiB
+        amdxdna_accel_driver-internal-alloc:	67588 KiB
+        amdxdna_accel_driver-external-alloc:	0
+        drm-total-memory:	67632 KiB
+        drm-shared-memory:	0
+
 
 References
 ==========
diff --git a/Documentation/gpu/drm-usage-stats.rst b/Documentation/gpu/drm-usage-stats.rst
index 63d6b2abe5ad..24d3012ca7a6 100644
--- a/Documentation/gpu/drm-usage-stats.rst
+++ b/Documentation/gpu/drm-usage-stats.rst
@@ -215,3 +215,4 @@ Driver specific implementations
 * :ref:`panfrost-usage-stats`
 * :ref:`panthor-usage-stats`
 * :ref:`xe-usage-stats`
+* :ref:`amdxdna-usage-stats`
diff --git a/drivers/accel/amdxdna/amdxdna_pci_drv.c b/drivers/accel/amdxdna/amdxdna_pci_drv.c
index 09d7d88bb6f1..21eddfc538d0 100644
--- a/drivers/accel/amdxdna/amdxdna_pci_drv.c
+++ b/drivers/accel/amdxdna/amdxdna_pci_drv.c
@@ -226,6 +226,35 @@ static const struct drm_ioctl_desc amdxdna_drm_ioctls[] = {
 	DRM_IOCTL_DEF_DRV(AMDXDNA_SET_STATE, amdxdna_drm_set_state_ioctl, DRM_ROOT_ONLY),
 };
 
+static void amdxdna_show_fdinfo(struct drm_printer *p, struct drm_file *filp)
+{
+	struct amdxdna_client *client = filp->driver_priv;
+	size_t heap_usage, external_usage, internal_usage;
+	char *drv_name = filp->minor->dev->driver->name;
+
+	mutex_lock(&client->mm_lock);
+
+	heap_usage = client->heap_usage;
+	internal_usage = client->total_int_bo_usage;
+	external_usage = client->total_bo_usage - internal_usage;
+
+	mutex_unlock(&client->mm_lock);
+
+	/*
+	 * Note for driver specific BO memory usage stat.
+	 * Total memory alloc = amdxdna-internal-alloc + amdxdna-external-alloc
+	 */
+	drm_fdinfo_print_size(p, drv_name, "heap", "alloc", heap_usage);
+	drm_fdinfo_print_size(p, drv_name, "internal", "alloc", internal_usage);
+	drm_fdinfo_print_size(p, drv_name, "external", "alloc", external_usage);
+	/*
+	 * Note for DRM standard BO memory stat.
+	 * drm-total-memory counts both DEV BO and HEAP BO
+	 * drm-shared-memory counts BO imported
+	 */
+	drm_show_memory_stats(p, filp);
+}
+
 static const struct file_operations amdxdna_fops = {
 	.owner		= THIS_MODULE,
 	.open		= accel_open,
@@ -236,6 +265,7 @@ static const struct file_operations amdxdna_fops = {
 	.read		= drm_read,
 	.llseek		= noop_llseek,
 	.mmap		= drm_gem_mmap,
+	.show_fdinfo	= drm_show_fdinfo,
 	.fop_flags	= FOP_UNSIGNED_OFFSET,
 };
 
@@ -251,7 +281,7 @@ const struct drm_driver amdxdna_drm_drv = {
 	.postclose = amdxdna_drm_close,
 	.ioctls = amdxdna_drm_ioctls,
 	.num_ioctls = ARRAY_SIZE(amdxdna_drm_ioctls),
-
+	.show_fdinfo = amdxdna_show_fdinfo,
 	.gem_create_object = amdxdna_gem_create_shmem_object_cb,
 	.gem_prime_import = amdxdna_gem_prime_import,
 };
-- 
2.34.1