Re: [Intel-xe] [PATCH 1/2] drm/xe/uapi: "Perf" layer to support multiple perf counter stream types

[Umesh Nerlige Ramappa <umesh.nerlige.ramappa@intel.com>]

On Wed, Oct 11, 2023 at 10:26:41AM -0700, Ashutosh Dixit wrote:
>In XE, the plan is to support multiple types of perf counter streams (OA is
>only one type of these streams). This requires addition of a PERF layer to
>multiplex these different stream types through a single set of PERF
>ioctl's.
>
>In addition to PERF DRM ioctl's, another set of ioctl's on the PERF fd are
>defined. These are expected to be common to different PERF stream types and
>therefore are defined at the PERF layer itself.
>
>v2: Add param_size to 'struct drm_xe_perf_param' (Umesh)
>v3: Rename 'enum drm_xe_perf_ops' to 'enum drm_xe_perf_ioctls' (Guy Zadicario)
>    Add DRM_ prefix to ioctl names to indicate uapi names
>
>Signed-off-by: Ashutosh Dixit <ashutosh.dixit@intel.com>
>---
> drivers/gpu/drm/xe/Makefile    |  1 +
> drivers/gpu/drm/xe/xe_device.c |  4 +++
> drivers/gpu/drm/xe/xe_perf.c   | 47 ++++++++++++++++++++++++++++++++
> drivers/gpu/drm/xe/xe_perf.h   | 18 +++++++++++++
> include/uapi/drm/xe_drm.h      | 49 ++++++++++++++++++++++++++++++++++
> 5 files changed, 119 insertions(+)
> create mode 100644 drivers/gpu/drm/xe/xe_perf.c
> create mode 100644 drivers/gpu/drm/xe/xe_perf.h
>
>diff --git a/drivers/gpu/drm/xe/Makefile b/drivers/gpu/drm/xe/Makefile
>index 175a357366d96..fb3eacbe3d6cb 100644
>--- a/drivers/gpu/drm/xe/Makefile
>+++ b/drivers/gpu/drm/xe/Makefile
>@@ -88,6 +88,7 @@ xe-y += xe_bb.o \
> 	xe_pat.o \
> 	xe_pci.o \
> 	xe_pcode.o \
>+	xe_perf.o \
> 	xe_pm.o \
> 	xe_preempt_fence.o \
> 	xe_pt.o \
>diff --git a/drivers/gpu/drm/xe/xe_device.c b/drivers/gpu/drm/xe/xe_device.c
>index ef42c33e30558..3c0c28c6f9fb8 100644
>--- a/drivers/gpu/drm/xe/xe_device.c
>+++ b/drivers/gpu/drm/xe/xe_device.c
>@@ -28,6 +28,7 @@
> #include "xe_module.h"
> #include "xe_pat.h"
> #include "xe_pcode.h"
>+#include "xe_perf.h"
> #include "xe_pm.h"
> #include "xe_query.h"
> #include "xe_tile.h"
>@@ -128,6 +129,9 @@ static const struct drm_ioctl_desc xe_ioctls[] = {
> 	DRM_IOCTL_DEF_DRV(XE_WAIT_USER_FENCE, xe_wait_user_fence_ioctl,
> 			  DRM_RENDER_ALLOW),
> 	DRM_IOCTL_DEF_DRV(XE_VM_MADVISE, xe_vm_madvise_ioctl, DRM_RENDER_ALLOW),
>+	DRM_IOCTL_DEF_DRV(XE_PERF_OPEN, xe_perf_open_ioctl, DRM_RENDER_ALLOW),
>+	DRM_IOCTL_DEF_DRV(XE_PERF_ADD_CONFIG, xe_perf_add_config_ioctl, DRM_RENDER_ALLOW),
>+	DRM_IOCTL_DEF_DRV(XE_PERF_REMOVE_CONFIG, xe_perf_remove_config_ioctl, DRM_RENDER_ALLOW),
> };
>
> static const struct file_operations xe_driver_fops = {
>diff --git a/drivers/gpu/drm/xe/xe_perf.c b/drivers/gpu/drm/xe/xe_perf.c
>new file mode 100644
>index 0000000000000..de430065e0d27
>--- /dev/null
>+++ b/drivers/gpu/drm/xe/xe_perf.c
>@@ -0,0 +1,47 @@
>+// SPDX-License-Identifier: MIT
>+/*
>+ * Copyright © 2023 Intel Corporation
>+ */
>+
>+#include <linux/errno.h>
>+
>+#include "xe_perf.h"
>+
>+int xe_perf_open_ioctl(struct drm_device *dev, void *data, struct drm_file *file)
>+{
>+	struct drm_xe_perf_param *arg = data;
>+
>+	if (arg->extensions)
>+		return -EINVAL;
>+
>+	switch (arg->perf_type) {
>+	default:
>+		return -EINVAL;
>+	}
>+}
>+
>+int xe_perf_add_config_ioctl(struct drm_device *dev, void *data, struct drm_file *file)
>+{
>+	struct drm_xe_perf_param *arg = data;
>+
>+	if (arg->extensions)
>+		return -EINVAL;
>+
>+	switch (arg->perf_type) {
>+	default:
>+		return -EINVAL;
>+	}
>+}
>+
>+int xe_perf_remove_config_ioctl(struct drm_device *dev, void *data, struct drm_file *file)
>+{
>+	struct drm_xe_perf_param *arg = data;
>+
>+	if (arg->extensions)
>+		return -EINVAL;
>+
>+	switch (arg->perf_type) {
>+	default:
>+		return -EINVAL;
>+	}
>+}

I would just squash the 2 patches here since this is a new interface and 
we don't care much about what existed earlier.

>diff --git a/drivers/gpu/drm/xe/xe_perf.h b/drivers/gpu/drm/xe/xe_perf.h
>new file mode 100644
>index 0000000000000..7ee90491132a0
>--- /dev/null
>+++ b/drivers/gpu/drm/xe/xe_perf.h
>@@ -0,0 +1,18 @@
>+/* SPDX-License-Identifier: MIT */
>+/*
>+ * Copyright © 2023 Intel Corporation
>+ */
>+
>+#ifndef _XE_PERF_H_
>+#define _XE_PERF_H_
>+
>+#include <drm/xe_drm.h>
>+
>+struct drm_device;
>+struct drm_file;
>+
>+int xe_perf_open_ioctl(struct drm_device *dev, void *data, struct drm_file *file);
>+int xe_perf_add_config_ioctl(struct drm_device *dev, void *data, struct drm_file *file);
>+int xe_perf_remove_config_ioctl(struct drm_device *dev, void *data, struct drm_file *file);
>+
>+#endif
>diff --git a/include/uapi/drm/xe_drm.h b/include/uapi/drm/xe_drm.h
>index d48d8e3c898ce..d734d2ee385b1 100644
>--- a/include/uapi/drm/xe_drm.h
>+++ b/include/uapi/drm/xe_drm.h
>@@ -111,6 +111,9 @@ struct xe_user_extension {
> #define DRM_XE_WAIT_USER_FENCE		0x0b
> #define DRM_XE_VM_MADVISE		0x0c
> #define DRM_XE_EXEC_QUEUE_GET_PROPERTY	0x0d
>+#define DRM_XE_PERF_OPEN		0x0e
>+#define DRM_XE_PERF_ADD_CONFIG		0x0f
>+#define DRM_XE_PERF_REMOVE_CONFIG	0x10
>
> /* Must be kept compact -- no holes */
> #define DRM_IOCTL_XE_DEVICE_QUERY		DRM_IOWR(DRM_COMMAND_BASE + DRM_XE_DEVICE_QUERY, struct drm_xe_device_query)
>@@ -127,6 +130,9 @@ struct xe_user_extension {
> #define DRM_IOCTL_XE_EXEC_QUEUE_SET_PROPERTY	 DRM_IOW(DRM_COMMAND_BASE + DRM_XE_EXEC_QUEUE_SET_PROPERTY, struct drm_xe_exec_queue_set_property)
> #define DRM_IOCTL_XE_WAIT_USER_FENCE		DRM_IOWR(DRM_COMMAND_BASE + DRM_XE_WAIT_USER_FENCE, struct drm_xe_wait_user_fence)
> #define DRM_IOCTL_XE_VM_MADVISE			 DRM_IOW(DRM_COMMAND_BASE + DRM_XE_VM_MADVISE, struct drm_xe_vm_madvise)
>+#define DRM_IOCTL_XE_PERF_OPEN			DRM_IOW(DRM_COMMAND_BASE + DRM_XE_PERF_OPEN, struct drm_xe_perf_param)
>+#define DRM_IOCTL_XE_PERF_ADD_CONFIG		DRM_IOW(DRM_COMMAND_BASE + DRM_XE_PERF_ADD_CONFIG, struct drm_xe_perf_param)
>+#define DRM_IOCTL_XE_PERF_REMOVE_CONFIG		DRM_IOW(DRM_COMMAND_BASE + DRM_XE_PERF_REMOVE_CONFIG, struct drm_xe_perf_param)
>
> /**
>  * enum drm_xe_memory_class - Supported memory classes.
>@@ -1093,6 +1099,49 @@ struct drm_xe_vm_madvise {
> #define XE_PMU_MEDIA_GROUP_BUSY(gt)		___XE_PMU_OTHER(gt, 3)
> #define XE_PMU_ANY_ENGINE_GROUP_BUSY(gt)	___XE_PMU_OTHER(gt, 4)
>
>+/**
>+ * enum drm_xe_perf_type - Perf stream types
>+ */
>+enum drm_xe_perf_type {
>+	DRM_XE_PERF_TYPE_MAX,
>+};
>+
>+/**
>+ * struct drm_xe_perf_param - XE perf layer param
>+ *
>+ * The perf layer enables multiplexing perf counter streams of multiple
>+ * types. The actual params for a particular stream operation are supplied
>+ * via the @param pointer (use __copy_from_user to get these params).
>+ */
>+struct drm_xe_perf_param {
>+	/** @extensions: Pointer to the first extension struct, if any */
>+	__u64 extensions;
>+	/** @perf_type: Perf stream type, of enum @drm_xe_perf_type */
>+	__u64 perf_type;
>+	/** @param_size: size of data struct pointed to by @param */
>+	__u64 param_size;

Since this structure is expandable using extensions, maybe we don't need 
to worry about the param_size. We can drop it. The size would matter if 
the only way to extend a structure was to add members to the end.

Thanks,
Umesh
>+	/** @param: Pointer to actual stream params */
>+	__u64 param;
>+};
>+
>+/**
>+ * enum drm_xe_perf_ioctls - Perf fd ioctl's
>+ */
>+enum drm_xe_perf_ioctls {
>+	/**
>+	 * @DRM_XE_PERF_IOCTL_ENABLE: Enable data capture for a stream that
>+	 * was e.g. either opened in a disabled state or was disabled via
>+	 * DRM_XE_PERF_IOCTL_DISABLE
>+	 */
>+	DRM_XE_PERF_IOCTL_ENABLE = _IO('i', 0x0),
>+
>+	/** @DRM_XE_PERF_IOCTL_DISABLE: Disable data capture for a stream */
>+	DRM_XE_PERF_IOCTL_DISABLE = _IO('i', 0x1),
>+
>+	/** @DRM_XE_PERF_IOCTL_CONFIG: Change stream configuration */
>+	DRM_XE_PERF_IOCTL_CONFIG = _IO('i', 0x2),
>+};
>+
> #if defined(__cplusplus)
> }
> #endif
>-- 
>2.41.0
>