On Tue, 20 May 2025 18:44:01 +0100
Adrián Larumbe <adrian.laru...@collabora.com> wrote:
> This change is essentially a Panfrost port of commit a3707f53eb3f
> ("drm/panthor: show device-wide list of DRM GEM objects over DebugFS").
>
> The DebugFS file is almost the same as in Panthor, minus the GEM object
> usage flags, since Panfrost has no kernel-only BO's.
>
> Two additional GEM state flags which are displayed but aren't relevant
> to Panthor are 'Purged' and 'Purgeable', since Panfrost implements an
> explicit shrinker and a madvise ioctl to flag objects as reclaimable.
>
> Signed-off-by: Adrián Larumbe <adrian.laru...@collabora.com>
Reviewed-by: Boris Brezillon <boris.brezil...@collabora.com>
> ---
> drivers/gpu/drm/panfrost/panfrost_device.c | 5 +
> drivers/gpu/drm/panfrost/panfrost_device.h | 15 +++
> drivers/gpu/drm/panfrost/panfrost_drv.c | 35 ++++++
> drivers/gpu/drm/panfrost/panfrost_gem.c | 134 +++++++++++++++++++++
> drivers/gpu/drm/panfrost/panfrost_gem.h | 47 ++++++++
> 5 files changed, 236 insertions(+)
>
> diff --git a/drivers/gpu/drm/panfrost/panfrost_device.c
> b/drivers/gpu/drm/panfrost/panfrost_device.c
> index 5d35076b2e6d..04bec27449cb 100644
> --- a/drivers/gpu/drm/panfrost/panfrost_device.c
> +++ b/drivers/gpu/drm/panfrost/panfrost_device.c
> @@ -209,6 +209,11 @@ int panfrost_device_init(struct panfrost_device *pfdev)
>
> spin_lock_init(&pfdev->cycle_counter.lock);
>
> +#ifdef CONFIG_DEBUG_FS
> + mutex_init(&pfdev->debugfs.gems_lock);
> + INIT_LIST_HEAD(&pfdev->debugfs.gems_list);
> +#endif
> +
> err = panfrost_pm_domain_init(pfdev);
> if (err)
> return err;
> diff --git a/drivers/gpu/drm/panfrost/panfrost_device.h
> b/drivers/gpu/drm/panfrost/panfrost_device.h
> index dcff70f905cd..077525a3ad68 100644
> --- a/drivers/gpu/drm/panfrost/panfrost_device.h
> +++ b/drivers/gpu/drm/panfrost/panfrost_device.h
> @@ -111,6 +111,17 @@ struct panfrost_compatible {
> u8 gpu_quirks;
> };
>
> +/**
> + * struct panfrost_device_debugfs - Device-wide DebugFS tracking structures
> + */
> +struct panfrost_device_debugfs {
> + /** @gems_list: Device-wide list of GEM objects owned by at least one
> file. */
> + struct list_head gems_list;
> +
> + /** @gems_lock: Serializes access to the device-wide list of GEM
> objects. */
> + struct mutex gems_lock;
> +};
> +
> struct panfrost_device {
> struct device *dev;
> struct drm_device *ddev;
> @@ -164,6 +175,10 @@ struct panfrost_device {
> atomic_t use_count;
> spinlock_t lock;
> } cycle_counter;
> +
> +#ifdef CONFIG_DEBUG_FS
> + struct panfrost_device_debugfs debugfs;
> +#endif
> };
>
> struct panfrost_mmu {
> diff --git a/drivers/gpu/drm/panfrost/panfrost_drv.c
> b/drivers/gpu/drm/panfrost/panfrost_drv.c
> index 179fbaa1cd0c..f576cb215898 100644
> --- a/drivers/gpu/drm/panfrost/panfrost_drv.c
> +++ b/drivers/gpu/drm/panfrost/panfrost_drv.c
> @@ -13,6 +13,7 @@
> #include <linux/platform_device.h>
> #include <linux/pm_runtime.h>
> #include <drm/panfrost_drm.h>
> +#include <drm/drm_debugfs.h>
> #include <drm/drm_drv.h>
> #include <drm/drm_ioctl.h>
> #include <drm/drm_syncobj.h>
> @@ -659,6 +660,37 @@ static const struct file_operations
> panfrost_drm_driver_fops = {
> .show_fdinfo = drm_show_fdinfo,
> };
>
> +#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 panfrost_device *pfdev = dev->dev_private;
> +
> + panfrost_gem_debugfs_print_bos(pfdev, 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 panfrost_debugfs_init(struct drm_minor *minor)
> +{
> + panthor_gems_debugfs_init(minor);
> +}
> +#endif
> +
> /*
> * Panfrost driver version:
> * - 1.0 - initial interface
> @@ -683,6 +715,9 @@ static const struct drm_driver panfrost_drm_driver = {
>
> .gem_create_object = panfrost_gem_create_object,
> .gem_prime_import_sg_table = panfrost_gem_prime_import_sg_table,
> +#ifdef CONFIG_DEBUG_FS
> + .debugfs_init = panfrost_debugfs_init,
> +#endif
> };
>
> static int panfrost_probe(struct platform_device *pdev)
> diff --git a/drivers/gpu/drm/panfrost/panfrost_gem.c
> b/drivers/gpu/drm/panfrost/panfrost_gem.c
> index 04483d5fb45d..bb73f2a68a12 100644
> --- a/drivers/gpu/drm/panfrost/panfrost_gem.c
> +++ b/drivers/gpu/drm/panfrost/panfrost_gem.c
> @@ -12,6 +12,36 @@
> #include "panfrost_gem.h"
> #include "panfrost_mmu.h"
>
> +#ifdef CONFIG_DEBUG_FS
> +static void panfrost_gem_debugfs_bo_add(struct panfrost_device *pfdev,
> + struct panfrost_gem_object *bo)
> +{
> + bo->debugfs.creator.tgid = current->group_leader->pid;
> + get_task_comm(bo->debugfs.creator.process_name, current->group_leader);
> +
> + mutex_lock(&pfdev->debugfs.gems_lock);
> + list_add_tail(&bo->debugfs.node, &pfdev->debugfs.gems_list);
> + mutex_unlock(&pfdev->debugfs.gems_lock);
> +}
> +
> +static void panfrost_gem_debugfs_bo_rm(struct panfrost_gem_object *bo)
> +{
> + struct panfrost_device *pfdev = bo->base.base.dev->dev_private;
> +
> + if (list_empty(&bo->debugfs.node))
> + return;
> +
> + mutex_lock(&pfdev->debugfs.gems_lock);
> + list_del_init(&bo->debugfs.node);
> + mutex_unlock(&pfdev->debugfs.gems_lock);
> +}
> +#else
> +static void panfrost_gem_debugfs_bo_add(struct panfrost_device *pfdev,
> + struct panfrost_gem_object *bo)
> +{}
> +static void panfrost_gem_debugfs_bo_rm(struct panfrost_gem_object *bo) {}
> +#endif
> +
> /* Called DRM core on the last userspace/kernel unreference of the
> * BO.
> */
> @@ -37,6 +67,7 @@ static void panfrost_gem_free_object(struct drm_gem_object
> *obj)
> WARN_ON_ONCE(!list_empty(&bo->mappings.list));
>
> kfree_const(bo->label.str);
> + panfrost_gem_debugfs_bo_rm(bo);
> mutex_destroy(&bo->label.lock);
>
> if (bo->sgts) {
> @@ -266,6 +297,8 @@ struct drm_gem_object *panfrost_gem_create_object(struct
> drm_device *dev, size_t
> obj->base.map_wc = !pfdev->coherent;
> mutex_init(&obj->label.lock);
>
> + panfrost_gem_debugfs_bo_add(pfdev, obj);
> +
> return &obj->base.base;
> }
>
> @@ -354,3 +387,104 @@ panfrost_gem_internal_set_label(struct drm_gem_object
> *obj, const char *label)
>
> panfrost_gem_set_label(obj, str);
> }
> +
> +#ifdef CONFIG_DEBUG_FS
> +struct gem_size_totals {
> + size_t size;
> + size_t resident;
> + size_t reclaimable;
> +};
> +
> +struct flag_def {
> + u32 flag;
> + const char *name;
> +};
> +
> +static void panfrost_gem_debugfs_print_flag_names(struct seq_file *m)
> +{
> + int len;
> + int i;
> +
> + static const struct flag_def gem_state_flags_names[] = {
> + {PANFROST_DEBUGFS_GEM_STATE_FLAG_IMPORTED, "imported"},
> + {PANFROST_DEBUGFS_GEM_STATE_FLAG_EXPORTED, "exported"},
> + {PANFROST_DEBUGFS_GEM_STATE_FLAG_PURGED, "purged"},
> + {PANFROST_DEBUGFS_GEM_STATE_FLAG_PURGEABLE, "purgeable"},
> + };
> +
> + seq_puts(m, "GEM state flags: ");
> + for (i = 0, len = ARRAY_SIZE(gem_state_flags_names); i < len; i++) {
> + seq_printf(m, "%s (0x%x)%s", gem_state_flags_names[i].name,
> + gem_state_flags_names[i].flag, (i < len - 1) ? ", "
> : "\n\n");
> + }
> +}
> +
> +static void panfrost_gem_debugfs_bo_print(struct panfrost_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] = {};
> + size_t resident_size;
> + u32 gem_state_flags = 0;
> +
> + /* Skip BOs being destroyed. */
> + if (!refcount)
> + return;
> +
> + resident_size = bo->base.pages ? bo->base.base.size : 0;
> +
> + snprintf(creator_info, sizeof(creator_info),
> + "%s/%d", bo->debugfs.creator.process_name,
> bo->debugfs.creator.tgid);
> + seq_printf(m, "%-32s%-16d%-16d%-16zd%-16zd0x%-16lx",
> + creator_info,
> + bo->base.base.name,
> + refcount,
> + bo->base.base.size,
> + resident_size,
> + drm_vma_node_start(&bo->base.base.vma_node));
> +
> + if (bo->base.base.import_attach)
> + gem_state_flags |= PANFROST_DEBUGFS_GEM_STATE_FLAG_IMPORTED;
> + if (bo->base.base.dma_buf)
> + gem_state_flags |= PANFROST_DEBUGFS_GEM_STATE_FLAG_EXPORTED;
> +
> + if (bo->base.madv < 0)
> + gem_state_flags |= PANFROST_DEBUGFS_GEM_STATE_FLAG_PURGED;
> + else if (bo->base.madv > 0)
> + gem_state_flags |= PANFROST_DEBUGFS_GEM_STATE_FLAG_PURGEABLE;
> +
> + seq_printf(m, "0x%-10x", gem_state_flags);
> +
> + scoped_guard(mutex, &bo->label.lock) {
> + seq_printf(m, "%s\n", bo->label.str ? : "");
> + }
> +
> + totals->size += bo->base.base.size;
> + totals->resident += resident_size;
> + if (bo->base.madv > 0)
> + totals->reclaimable += resident_size;
> +}
> +
> +void panfrost_gem_debugfs_print_bos(struct panfrost_device *pfdev,
> + struct seq_file *m)
> +{
> + struct gem_size_totals totals = {0};
> + struct panfrost_gem_object *bo;
> +
> + panfrost_gem_debugfs_print_flag_names(m);
> +
> + seq_puts(m, "created-by global-name refcount
> size resident-size file-offset state label\n");
> + seq_puts(m,
> "-----------------------------------------------------------------------------------------------------------------------------------\n");
> +
> + scoped_guard(mutex, &pfdev->debugfs.gems_lock) {
> + list_for_each_entry(bo, &pfdev->debugfs.gems_list,
> debugfs.node) {
> + panfrost_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/panfrost/panfrost_gem.h
> b/drivers/gpu/drm/panfrost/panfrost_gem.h
> index 3d87c41ad09d..8de3e76f2717 100644
> --- a/drivers/gpu/drm/panfrost/panfrost_gem.h
> +++ b/drivers/gpu/drm/panfrost/panfrost_gem.h
> @@ -8,9 +8,47 @@
> #include <drm/drm_mm.h>
>
> struct panfrost_mmu;
> +struct panfrost_device;
>
> #define PANFROST_BO_LABEL_MAXLEN 4096
>
> +enum panfrost_debugfs_gem_state_flags {
> + /** @PANFROST_DEBUGFS_GEM_STATE_FLAG_IMPORTED: GEM BO is PRIME
> imported. */
> + PANFROST_DEBUGFS_GEM_STATE_FLAG_IMPORTED = BIT(0),
> +
> + /** @PANFROST_DEBUGFS_GEM_STATE_FLAG_EXPORTED: GEM BO is PRIME
> exported. */
> + PANFROST_DEBUGFS_GEM_STATE_FLAG_EXPORTED = BIT(1),
> +
> + /** @PANFROST_DEBUGFS_GEM_STATE_FLAG_PURGED: GEM BO was reclaimed by
> the shrinker. */
> + PANFROST_DEBUGFS_GEM_STATE_FLAG_PURGED = BIT(2),
> +
> + /**
> + * @PANFROST_DEBUGFS_GEM_STATE_FLAG_PURGEABLE: GEM BO pages were marked
> as no longer
> + * needed by UM and can be reclaimed by the shrinker.
> + */
> + PANFROST_DEBUGFS_GEM_STATE_FLAG_PURGEABLE = BIT(3),
> +};
> +
> +/**
> + * struct panfrost_gem_debugfs - GEM object's DebugFS list information
> + */
> +struct panfrost_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 panfrost_gem_object {
> struct drm_gem_shmem_object base;
> struct sg_table *sgts;
> @@ -59,6 +97,10 @@ struct panfrost_gem_object {
>
> bool noexec :1;
> bool is_heap :1;
> +
> +#ifdef CONFIG_DEBUG_FS
> + struct panfrost_gem_debugfs debugfs;
> +#endif
> };
>
> struct panfrost_gem_mapping {
> @@ -108,4 +150,9 @@ void panfrost_gem_shrinker_cleanup(struct drm_device
> *dev);
> void panfrost_gem_set_label(struct drm_gem_object *obj, const char *label);
> void panfrost_gem_internal_set_label(struct drm_gem_object *obj, const char
> *label);
>
> +#ifdef CONFIG_DEBUG_FS
> +void panfrost_gem_debugfs_print_bos(struct panfrost_device *pfdev,
> + struct seq_file *m);
> +#endif
> +
> #endif /* __PANFROST_GEM_H__ */
