From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from bali.collaboradmins.com (bali.collaboradmins.com [148.251.105.195]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 27530238D5A; Wed, 2 Apr 2025 12:58:10 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=148.251.105.195 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1743598693; cv=none; b=JEhyBUZe/P0YOo1AO+QQMggoVhUoWtvVX581BUnvtMSmgzI14AqVctjYFR6XLD1X/n+jj839JM8+iwmWdBSSRNkBwst/IkbWXF804OIX59DKO6TfYoX3+9uCrHncP0kydZoulDugOMlAbpz+keN4JPKpOJ3z8eskGbosvBtWKw0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1743598693; c=relaxed/simple; bh=UK42PdnMtf0Qa5rMpsbgRc0+I+IawzFM3jt4sOSw3C0=; h=Date:From:To:Cc:Subject:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=uW65lmbSkdp8zQZoA3hibTqzjihsq8upm5ZcTRpCFChGYjFiHpcpdjrb6G2uXn9NDRyzsLpUBZ7/AYMok+MrdUsoydVF9iXRIxKQX9eao3/QqNWXQPfLl/j6yxtnPlbbroXXULli5fj6Rn9tQJgwrA/6PHeWipuxZL3dW2GFeYI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=collabora.com; spf=pass smtp.mailfrom=collabora.com; dkim=pass (2048-bit key) header.d=collabora.com header.i=@collabora.com header.b=AX5LkIwZ; arc=none smtp.client-ip=148.251.105.195 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=collabora.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=collabora.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=collabora.com header.i=@collabora.com header.b="AX5LkIwZ" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=collabora.com; s=mail; t=1743598689; bh=UK42PdnMtf0Qa5rMpsbgRc0+I+IawzFM3jt4sOSw3C0=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=AX5LkIwZQUhw0VHtm8dOT70p9dlZA5aMbbBsDM+5v3iZLrd3aZ2ltQ7TEh2hpR4Yf Y1Yh4ptpTjc3V/wtZ2QVPOT82RjojLEnIrLMZ6soHNhCZEBJaiLBRpi2FJ6uHhDHt+ 6db3vc7I1j1SvVy0JJQR/vRcpgkkw6P/uA1MN4nvl/xVwdK3Tpae6hpRfYSXV/Z1o3 W+3r85QRruiwHy+IMUDq/QnbswjxuDKdooP3+eEr2un9XnmXIlfKUpBpCYh21aO1vE 9GlKwFKxMvvRZEJtcKmCCAHRHPy9LBSZagmoWESnUX8vGx6Xn9aM7S6w3QXdX/vHWf nO6skZ274TGHA== Received: from localhost (unknown [IPv6:2a01:e0a:2c:6930:5cf4:84a1:2763:fe0d]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) (Authenticated sender: bbrezillon) by bali.collaboradmins.com (Postfix) with ESMTPSA id 9DEDE17E0865; Wed, 2 Apr 2025 14:58:08 +0200 (CEST) Date: Wed, 2 Apr 2025 14:58:04 +0200 From: Boris Brezillon To: =?UTF-8?B?QWRyacOhbg==?= Larumbe Cc: Steven Price , Liviu Dudau , Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , David Airlie , Simona Vetter , Sumit Semwal , Christian =?UTF-8?B?S8O2bmln?= , kernel@collabora.com, dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, linux-media@vger.kernel.org, linaro-mm-sig@lists.linaro.org Subject: Re: [PATCH v4 4/4] drm/panthor: show device-wide list of DRM GEM objects over DebugFS Message-ID: <20250402145804.5cf07f5e@collabora.com> In-Reply-To: <20250402115432.1469703-5-adrian.larumbe@collabora.com> References: <20250402115432.1469703-1-adrian.larumbe@collabora.com> <20250402115432.1469703-5-adrian.larumbe@collabora.com> Organization: Collabora X-Mailer: Claws Mail 4.3.0 (GTK 3.24.43; x86_64-redhat-linux-gnu) Precedence: bulk X-Mailing-List: linux-media@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable On Wed, 2 Apr 2025 12:54:29 +0100 Adri=C3=A1n Larumbe 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. >=20 > 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. >=20 > File format is that of a table, with each entry displaying a variety of > fields with information about each GEM object. >=20 > 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. >=20 > There's also a kflags field for the type of BO. Bit 0 tells us whether > it's a kernel BO, and bit 1 means the BO is mapped onto the FW's address > space. >=20 > Signed-off-by: Adri=C3=A1n Larumbe > --- > 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 | 149 +++++++++++++++++++++++ > drivers/gpu/drm/panthor/panthor_gem.h | 35 ++++++ > 5 files changed, 226 insertions(+) >=20 > diff --git a/drivers/gpu/drm/panthor/panthor_device.c b/drivers/gpu/drm/p= anthor/panthor_device.c > index a9da1d1eeb70..b776e1a2e4f3 100644 > --- a/drivers/gpu/drm/panthor/panthor_device.c > +++ b/drivers/gpu/drm/panthor/panthor_device.c > @@ -184,6 +184,11 @@ int panthor_device_init(struct panthor_device *ptdev) > if (ret) > return ret; > =20 > +#ifdef CONFIG_DEBUG_FS > + drmm_mutex_init(&ptdev->base, &ptdev->gems.lock); > + INIT_LIST_HEAD(&ptdev->gems.node); > +#endif > + > atomic_set(&ptdev->pm.state, PANTHOR_DEVICE_PM_STATE_SUSPENDED); > p =3D alloc_page(GFP_KERNEL | __GFP_ZERO); > if (!p) > diff --git a/drivers/gpu/drm/panthor/panthor_device.h b/drivers/gpu/drm/p= anthor/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 { > =20 > /** @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 > }; > =20 > struct panthor_gpu_usage { > diff --git a/drivers/gpu/drm/panthor/panthor_drv.c b/drivers/gpu/drm/pant= hor/panthor_drv.c > index d5277284fe27..3e870ed2ad90 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_dr= iver_fops =3D { > }; > =20 > #ifdef CONFIG_DEBUG_FS > +static int panthor_gems_show(struct seq_file *m, void *data) > +{ > + struct drm_info_node *node =3D m->private; > + struct drm_device *dev =3D node->minor->dev; > + struct panthor_device *ptdev =3D container_of(dev, struct panthor_devic= e, base); > + > + panthor_gem_debugfs_print_bos(ptdev, m); > + > + return 0; > +} > + > + > +static struct drm_info_list panthor_debugfs_list[] =3D { > + {"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 > =20 > diff --git a/drivers/gpu/drm/panthor/panthor_gem.c b/drivers/gpu/drm/pant= hor/panthor_gem.c > index 44d027e6d664..2fc87be9b700 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 */ > /* Copyright 2023 Collabora ltd. */ > =20 > +#include > #include > #include > #include > @@ -10,14 +11,65 @@ > #include > =20 > #include "panthor_device.h" > +#include "panthor_fw.h" > #include "panthor_gem.h" > #include "panthor_mmu.h" > =20 > +#ifdef CONFIG_DEBUG_FS > +static void panthor_gem_debugfs_bo_init(struct panthor_gem_object *bo, u= 32 type_mask) > +{ > + INIT_LIST_HEAD(&bo->debugfs.node); This should be called when the GEM object is created, otherwise the list_empty() test done in panthor_gem_debugfs_bo_rm() will only work if panthor_gem_debugfs_bo_add() is called, and depending on when this happens, or whether it happens at all, the error path will do a NULL deref. > + > + if (!(type_mask & PANTHOR_BO_FW_MAPPED)) { > + bo->debugfs.creator.tgid =3D current->group_leader->pid; > + get_task_comm(bo->debugfs.creator.process_name, current->group_leader); I don't think that's good to assume that FW-mapped BOs have been created by the kernel without userspace directly or indirectly asking for the allocation. For instance, per-group memory allocated for the USER_CS interfaces are indirectly triggered by a GROUP_CREATE ioctl(), and should IMO be flagged as being created by the process that created the group. Don't we have another way to check if we're called from a kernel thread? > + } else { > + bo->debugfs.creator.tgid =3D 0; > + snprintf(bo->debugfs.creator.process_name, > + sizeof(bo->debugfs.creator.process_name), > + "kernel"); > + } > + > + bo->debugfs.bo_mask =3D type_mask; Why not do that directly in panthor_gem_debugfs_bo_add()? The only bits that might be useful to do early is the INIT_LIST_HEAD(), and I think it can be inlined in panthor_gem_create_object(). > +} > + > +static void panthor_gem_debugfs_bo_add(struct panthor_gem_object *bo, u3= 2 type_mask) > +{ > + struct panthor_device *ptdev =3D container_of(bo->base.base.dev, > + struct panthor_device, base); > + > + panthor_gem_debugfs_bo_init(bo, type_mask); > + > + mutex_lock(&ptdev->gems.lock); > + list_add_tail(&bo->debugfs.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 =3D container_of(bo->base.base.dev, > + struct panthor_device, base); > + > + if (list_empty(&bo->debugfs.node)) > + return; > + > + mutex_lock(&ptdev->gems.lock); > + list_del_init(&bo->debugfs.node); > + mutex_unlock(&ptdev->gems.lock); > +} > + > +#else > +static void panthor_gem_debugfs_bo_add(struct panthor_gem_object *bo, u3= 2 type_mask) {} > +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 =3D to_panthor_bo(obj); > struct drm_gem_object *vm_root_gem =3D bo->exclusive_vm_root_gem; > =20 > + 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 > @@ -86,6 +138,7 @@ panthor_kernel_bo_create(struct panthor_device *ptdev,= struct panthor_vm *vm, > struct drm_gem_shmem_object *obj; > struct panthor_kernel_bo *kbo; > struct panthor_gem_object *bo; > + u32 type_mask =3D PANTHOR_BO_KERNEL; > int ret; > =20 > if (drm_WARN_ON(&ptdev->base, !vm)) > @@ -105,7 +158,12 @@ panthor_kernel_bo_create(struct panthor_device *ptde= v, struct panthor_vm *vm, > kbo->obj =3D &obj->base; > bo->flags =3D bo_flags; > =20 > + if (vm =3D=3D panthor_fw_vm(ptdev)) > + type_mask |=3D PANTHOR_BO_FW_MAPPED; > + > panthor_gem_kernel_bo_set_label(kbo, name); > + panthor_gem_debugfs_bo_add(to_panthor_bo(kbo->obj), type_mask); > + > /* The system and GPU MMU page size might differ, which becomes a > * problem for FW sections that need to be mapped at explicit address > * since our PAGE_SIZE alignment might cover a VA range that's > @@ -255,6 +313,8 @@ panthor_gem_create_with_handle(struct drm_file *file, > /* drop reference from allocate - handle holds it now. */ > drm_gem_object_put(&shmem->base); > =20 > + panthor_gem_debugfs_bo_add(bo, 0); > + > return ret; > } > =20 > @@ -286,3 +346,92 @@ panthor_gem_kernel_bo_set_label(struct panthor_kerne= l_bo *bo, const char *label) > =20 > 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 =3D kref_read(&bo->base.base.refcount); > + char creator_info[32] =3D {}; > + bool has_flags =3D false; > + size_t resident_size; > + > + /* Skip BOs being destroyed. */ > + if (!refcount) > + return; > + > + resident_size =3D bo->base.pages !=3D NULL ? 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%-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 =3D panfrost_gem_print_flag("imported", bo->base.base.import_= attach !=3D NULL, > + has_flags, m); > + has_flags =3D panfrost_gem_print_flag("exported", bo->base.base.dma_buf= !=3D NULL, > + has_flags, m); > + if (bo->base.madv < 0) > + has_flags =3D panfrost_gem_print_flag("purged", true, has_flags, m); > + else if (bo->base.madv > 0) > + has_flags =3D panfrost_gem_print_flag("purgeable", true, has_flags, m); > + if (!has_flags) > + seq_puts(m, "none"); > + seq_puts(m, ")"); > + > + seq_printf(m, "%-6s0x%-2x", "", bo->debugfs.bo_mask); > + > + mutex_lock(&bo->label.lock); > + seq_printf(m, "%-6s%-60s", "", bo->label.str ? : NULL); > + mutex_unlock(&bo->label.lock); > + seq_puts(m, "\n"); > + > + totals->size +=3D bo->base.base.size; > + totals->resident +=3D resident_size; > + if (bo->base.madv > 0) > + totals->reclaimable +=3D resident_size; > +} > + > +void panthor_gem_debugfs_print_bos(struct panthor_device *ptdev, > + struct seq_file *m) > +{ > + struct gem_size_totals totals =3D {0}; > + struct panthor_gem_object *bo; > + > + seq_puts(m, "created-by global-name refcount = size resident-size file-offset flags kflags = label\n"); > + seq_puts(m, "----------------------------------------------------------= ---------------------------------------------------------------------------= -----------\n"); > + > + scoped_guard(mutex, &ptdev->gems.lock) { > + list_for_each_entry(bo, &ptdev->gems.node, debugfs.node) > + panthor_gem_debugfs_bo_print(bo, m, &totals); > + } > + > + seq_puts(m, "=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D\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/pant= hor/panthor_gem.h > index 49daa5088a0d..22ecc0d39d5e 100644 > --- a/drivers/gpu/drm/panthor/panthor_gem.h > +++ b/drivers/gpu/drm/panthor/panthor_gem.h > @@ -15,6 +15,32 @@ struct panthor_vm; > =20 > #define PANTHOR_BO_LABEL_MAXLEN PAGE_SIZE > =20 > +#define PANTHOR_BO_KERNEL BIT(0) > +#define PANTHOR_BO_FW_MAPPED BIT(1) > + > +/** > + * 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 proces= s */ > + char process_name[TASK_COMM_LEN]; > + > + /** @creator.tgid: PID of the thread's group leader within its process= */ > + pid_t tgid; > + } creator; > + > + /** @bo_mask: Bitmask encoding BO type as {USER, KERNEL} x {GPU, FW} */ > + u32 bo_mask; > +}; > + > /** > * struct panthor_gem_object - Driver specific GEM object. > */ > @@ -62,6 +88,10 @@ 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 debugfs; > +#endif > }; > =20 > /** > @@ -157,4 +187,9 @@ panthor_kernel_bo_create(struct panthor_device *ptdev= , struct panthor_vm *vm, > =20 > void panthor_kernel_bo_destroy(struct panthor_kernel_bo *bo); > =20 > +#ifdef CONFIG_DEBUG_FS > +void panthor_gem_debugfs_print_bos(struct panthor_device *pfdev, > + struct seq_file *m); > +#endif > + > #endif /* __PANTHOR_GEM_H__ */