[PATCH drm-next v7 03/13] drm: debugfs: provide infrastructure to dump a DRM GPU VA space

From: Danilo Krummrich
Date: Thu Jul 13 2023 - 13:05:51 EST


This commit adds a function to dump a DRM GPU VA space and a macro for
drivers to register the struct drm_info_list 'gpuvas' entry.

Most likely, most drivers might maintain one DRM GPU VA space per struct
drm_file, but there might also be drivers not having a fixed relation
between DRM GPU VA spaces and a DRM core infrastructure, hence we need the
indirection via the driver iterating it's maintained DRM GPU VA spaces.

Reviewed-by: Boris Brezillon <boris.brezillon@xxxxxxxxxxxxx>
Signed-off-by: Danilo Krummrich <dakr@xxxxxxxxxx>
---
drivers/gpu/drm/drm_debugfs.c | 40 +++++++++++++++++++++++++++++++++++
include/drm/drm_debugfs.h | 25 ++++++++++++++++++++++
2 files changed, 65 insertions(+)

diff --git a/drivers/gpu/drm/drm_debugfs.c b/drivers/gpu/drm/drm_debugfs.c
index 4855230ba2c6..c90dbcffa0dc 100644
--- a/drivers/gpu/drm/drm_debugfs.c
+++ b/drivers/gpu/drm/drm_debugfs.c
@@ -39,6 +39,7 @@
#include <drm/drm_file.h>
#include <drm/drm_gem.h>
#include <drm/drm_managed.h>
+#include <drm/drm_gpuva_mgr.h>

#include "drm_crtc_internal.h"
#include "drm_internal.h"
@@ -175,6 +176,45 @@ static const struct file_operations drm_debugfs_fops = {
.release = single_release,
};

+/**
+ * drm_debugfs_gpuva_info - dump the given DRM GPU VA space
+ * @m: pointer to the &seq_file to write
+ * @mgr: the &drm_gpuva_manager representing the GPU VA space
+ *
+ * Dumps the GPU VA mappings of a given DRM GPU VA manager.
+ *
+ * For each DRM GPU VA space drivers should call this function from their
+ * &drm_info_list's show callback.
+ *
+ * Returns: 0 on success, -ENODEV if the &mgr is not initialized
+ */
+int drm_debugfs_gpuva_info(struct seq_file *m,
+ struct drm_gpuva_manager *mgr)
+{
+ struct drm_gpuva *va, *kva = &mgr->kernel_alloc_node;
+
+ if (!mgr->name)
+ return -ENODEV;
+
+ seq_printf(m, "DRM GPU VA space (%s) [0x%016llx;0x%016llx]\n",
+ mgr->name, mgr->mm_start, mgr->mm_start + mgr->mm_range);
+ seq_printf(m, "Kernel reserved node [0x%016llx;0x%016llx]\n",
+ kva->va.addr, kva->va.addr + kva->va.range);
+ seq_puts(m, "\n");
+ seq_puts(m, " VAs | start | range | end | object | object offset\n");
+ seq_puts(m, "-------------------------------------------------------------------------------------------------------------\n");
+ drm_gpuva_for_each_va(va, mgr) {
+ if (unlikely(va == kva))
+ continue;
+
+ seq_printf(m, " | 0x%016llx | 0x%016llx | 0x%016llx | 0x%016llx | 0x%016llx\n",
+ va->va.addr, va->va.range, va->va.addr + va->va.range,
+ (u64)va->gem.obj, va->gem.offset);
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL(drm_debugfs_gpuva_info);

/**
* drm_debugfs_create_files - Initialize a given set of debugfs files for DRM
diff --git a/include/drm/drm_debugfs.h b/include/drm/drm_debugfs.h
index 7616f457ce70..cb2c1956a214 100644
--- a/include/drm/drm_debugfs.h
+++ b/include/drm/drm_debugfs.h
@@ -34,6 +34,22 @@

#include <linux/types.h>
#include <linux/seq_file.h>
+
+#include <drm/drm_gpuva_mgr.h>
+
+/**
+ * DRM_DEBUGFS_GPUVA_INFO - &drm_info_list entry to dump a GPU VA space
+ * @show: the &drm_info_list's show callback
+ * @data: driver private data
+ *
+ * Drivers should use this macro to define a &drm_info_list entry to provide a
+ * debugfs file for dumping the GPU VA space regions and mappings.
+ *
+ * For each DRM GPU VA space drivers should call drm_debugfs_gpuva_info() from
+ * their @show callback.
+ */
+#define DRM_DEBUGFS_GPUVA_INFO(show, data) {"gpuvas", show, DRIVER_GEM_GPUVA, data}
+
/**
* struct drm_info_list - debugfs info list entry
*
@@ -134,6 +150,9 @@ void drm_debugfs_add_file(struct drm_device *dev, const char *name,

void drm_debugfs_add_files(struct drm_device *dev,
const struct drm_debugfs_info *files, int count);
+
+int drm_debugfs_gpuva_info(struct seq_file *m,
+ struct drm_gpuva_manager *mgr);
#else
static inline void drm_debugfs_create_files(const struct drm_info_list *files,
int count, struct dentry *root,
@@ -155,6 +174,12 @@ static inline void drm_debugfs_add_files(struct drm_device *dev,
const struct drm_debugfs_info *files,
int count)
{}
+
+static inline int drm_debugfs_gpuva_info(struct seq_file *m,
+ struct drm_gpuva_manager *mgr)
+{
+ return 0;
+}
#endif

#endif /* _DRM_DEBUGFS_H_ */
--
2.41.0