drm/xe/uapi: Rename xe perf layer as xe observation layer

In Xe, the perf layer allows capture of HW counter streams. These HW
counters are generally performance related but don't have to be necessarily
so. Also, the name "perf" is a carryover from i915 and is not preferred.

Here we propose the name "observation" for this common layer which allows
capture of different types of these counter streams.

v2: Rename observability layer to observation layer (Lucas/Rodrigo)
v3: Rename sysctl file to "observation_paranoid" (Jose)

Fixes: 52c2e95 ("drm/xe/perf/uapi: "Perf" layer to support multiple perf counter stream types")
Fixes: fe8929b ("drm/xe/perf/uapi: Add perf_stream_paranoid sysctl")
Acked-by: Lucas De Marchi <[email protected]>
Acked-by: Rodrigo Vivi <[email protected]>
Signed-off-by: Ashutosh Dixit <[email protected]>
Reviewed-by: Umesh Nerlige Ramappa <[email protected]>
Acked-by: José Roberto de Souza <[email protected]>
Link: https://patchwork.freedesktop.org/patch/msgid/[email protected]
(cherry picked from commit 8169b20)
Signed-off-by: Rodrigo Vivi <[email protected]>

Author: ashutoshx

drivers/gpu/drm/xe/Makefile

@@ -96,10 +96,10 @@ xe-y += xe_bb.o \
 	xe_mocs.o \
 	xe_module.o \
 	xe_oa.o \
+	xe_observation.o \
 	xe_pat.o \
 	xe_pci.o \
 	xe_pcode.o \
-	xe_perf.o \
 	xe_pm.o \
 	xe_preempt_fence.o \
 	xe_pt.o \

drivers/gpu/drm/xe/xe_device.c

@@ -42,9 +42,9 @@
 #include "xe_memirq.h"
 #include "xe_mmio.h"
 #include "xe_module.h"
+#include "xe_observation.h"
 #include "xe_pat.h"
 #include "xe_pcode.h"
-#include "xe_perf.h"
 #include "xe_pm.h"
 #include "xe_query.h"
 #include "xe_sriov.h"
@@ -142,7 +142,7 @@ static const struct drm_ioctl_desc xe_ioctls[] = {
 			  DRM_RENDER_ALLOW),
 	DRM_IOCTL_DEF_DRV(XE_WAIT_USER_FENCE, xe_wait_user_fence_ioctl,
 			  DRM_RENDER_ALLOW),
-	DRM_IOCTL_DEF_DRV(XE_PERF, xe_perf_ioctl, DRM_RENDER_ALLOW),
+	DRM_IOCTL_DEF_DRV(XE_OBSERVATION, xe_observation_ioctl, DRM_RENDER_ALLOW),
 };
 
 static long xe_drm_ioctl(struct file *file, unsigned int cmd, unsigned long arg)

drivers/gpu/drm/xe/xe_device_types.h

@@ -463,7 +463,7 @@ struct xe_device {
 	/** @heci_gsc: graphics security controller */
 	struct xe_heci_gsc heci_gsc;
 
-	/** @oa: oa perf counter subsystem */
+	/** @oa: oa observation subsystem */
 	struct xe_oa oa;
 
 	/** @needs_flr_on_fini: requests function-reset on fini */

drivers/gpu/drm/xe/xe_gt_types.h

@@ -389,7 +389,7 @@ struct xe_gt {
 		u8 instances_per_class[XE_ENGINE_CLASS_MAX];
 	} user_engines;
 
-	/** @oa: oa perf counter subsystem per gt info */
+	/** @oa: oa observation subsystem per gt info */
 	struct xe_oa_gt oa;
 };
 

drivers/gpu/drm/xe/xe_module.c

@@ -11,7 +11,7 @@
 #include "xe_drv.h"
 #include "xe_hw_fence.h"
 #include "xe_pci.h"
-#include "xe_perf.h"
+#include "xe_observation.h"
 #include "xe_sched_job.h"
 
 struct xe_modparam xe_modparam = {
@@ -80,8 +80,8 @@ static const struct init_funcs init_funcs[] = {
 		.exit = xe_unregister_pci_driver,
 	},
 	{
-		.init = xe_perf_sysctl_register,
-		.exit = xe_perf_sysctl_unregister,
+		.init = xe_observation_sysctl_register,
+		.exit = xe_observation_sysctl_unregister,
 	},
 };
 

drivers/gpu/drm/xe/xe_oa.c

@@ -32,7 +32,7 @@
 #include "xe_macros.h"
 #include "xe_mmio.h"
 #include "xe_oa.h"
-#include "xe_perf.h"
+#include "xe_observation.h"
 #include "xe_pm.h"
 #include "xe_sched_job.h"
 #include "xe_sriov.h"
@@ -481,7 +481,7 @@ static int __xe_oa_read(struct xe_oa_stream *stream, char __user *buf,
 					  OASTATUS_RELEVANT_BITS, 0);
 	/*
 	 * Signal to userspace that there is non-zero OA status to read via
-	 * @DRM_XE_PERF_IOCTL_STATUS perf fd ioctl
+	 * @DRM_XE_OBSERVATION_IOCTL_STATUS observation stream fd ioctl
 	 */
 	if (stream->oa_status & OASTATUS_RELEVANT_BITS)
 		return -EIO;
@@ -1158,15 +1158,15 @@ static long xe_oa_ioctl_locked(struct xe_oa_stream *stream,
 			       unsigned long arg)
 {
 	switch (cmd) {
-	case DRM_XE_PERF_IOCTL_ENABLE:
+	case DRM_XE_OBSERVATION_IOCTL_ENABLE:
 		return xe_oa_enable_locked(stream);
-	case DRM_XE_PERF_IOCTL_DISABLE:
+	case DRM_XE_OBSERVATION_IOCTL_DISABLE:
 		return xe_oa_disable_locked(stream);
-	case DRM_XE_PERF_IOCTL_CONFIG:
+	case DRM_XE_OBSERVATION_IOCTL_CONFIG:
 		return xe_oa_config_locked(stream, arg);
-	case DRM_XE_PERF_IOCTL_STATUS:
+	case DRM_XE_OBSERVATION_IOCTL_STATUS:
 		return xe_oa_status_locked(stream, arg);
-	case DRM_XE_PERF_IOCTL_INFO:
+	case DRM_XE_OBSERVATION_IOCTL_INFO:
 		return xe_oa_info_locked(stream, arg);
 	}
 
@@ -1209,7 +1209,7 @@ static int xe_oa_release(struct inode *inode, struct file *file)
 	xe_oa_destroy_locked(stream);
 	mutex_unlock(&gt->oa.gt_lock);
 
-	/* Release the reference the perf stream kept on the driver */
+	/* Release the reference the OA stream kept on the driver */
 	drm_dev_put(&gt_to_xe(gt)->drm);
 
 	return 0;
@@ -1222,7 +1222,7 @@ static int xe_oa_mmap(struct file *file, struct vm_area_struct *vma)
 	unsigned long start = vma->vm_start;
 	int i, ret;
 
-	if (xe_perf_stream_paranoid && !perfmon_capable()) {
+	if (xe_observation_paranoid && !perfmon_capable()) {
 		drm_dbg(&stream->oa->xe->drm, "Insufficient privilege to map OA buffer\n");
 		return -EACCES;
 	}
@@ -1789,8 +1789,8 @@ static int xe_oa_user_extensions(struct xe_oa *oa, u64 extension, int ext_number
  * @file: @drm_file
  *
  * The functions opens an OA stream. An OA stream, opened with specified
- * properties, enables perf counter samples to be collected, either
- * periodically (time based sampling), or on request (using perf queries)
+ * properties, enables OA counter samples to be collected, either
+ * periodically (time based sampling), or on request (using OA queries)
  */
 int xe_oa_stream_open_ioctl(struct drm_device *dev, u64 data, struct drm_file *file)
 {
@@ -1836,8 +1836,8 @@ int xe_oa_stream_open_ioctl(struct drm_device *dev, u64 data, struct drm_file *f
 		privileged_op = true;
 	}
 
-	if (privileged_op && xe_perf_stream_paranoid && !perfmon_capable()) {
-		drm_dbg(&oa->xe->drm, "Insufficient privileges to open xe perf stream\n");
+	if (privileged_op && xe_observation_paranoid && !perfmon_capable()) {
+		drm_dbg(&oa->xe->drm, "Insufficient privileges to open xe OA stream\n");
 		ret = -EACCES;
 		goto err_exec_q;
 	}
@@ -2097,7 +2097,7 @@ int xe_oa_add_config_ioctl(struct drm_device *dev, u64 data, struct drm_file *fi
 		return -ENODEV;
 	}
 
-	if (xe_perf_stream_paranoid && !perfmon_capable()) {
+	if (xe_observation_paranoid && !perfmon_capable()) {
 		drm_dbg(&oa->xe->drm, "Insufficient privileges to add xe OA config\n");
 		return -EACCES;
 	}
@@ -2181,7 +2181,7 @@ int xe_oa_add_config_ioctl(struct drm_device *dev, u64 data, struct drm_file *fi
 /**
  * xe_oa_remove_config_ioctl - Removes one OA config
  * @dev: @drm_device
- * @data: pointer to struct @drm_xe_perf_param
+ * @data: pointer to struct @drm_xe_observation_param
  * @file: @drm_file
  */
 int xe_oa_remove_config_ioctl(struct drm_device *dev, u64 data, struct drm_file *file)
@@ -2197,7 +2197,7 @@ int xe_oa_remove_config_ioctl(struct drm_device *dev, u64 data, struct drm_file
 		return -ENODEV;
 	}
 
-	if (xe_perf_stream_paranoid && !perfmon_capable()) {
+	if (xe_observation_paranoid && !perfmon_capable()) {
 		drm_dbg(&oa->xe->drm, "Insufficient privileges to remove xe OA config\n");
 		return -EACCES;
 	}
@@ -2381,7 +2381,7 @@ static int xe_oa_init_gt(struct xe_gt *gt)
 
 	/*
 	 * Fused off engines can result in oa_unit's with num_engines == 0. These units
-	 * will appear in OA unit query, but no perf streams can be opened on them.
+	 * will appear in OA unit query, but no OA streams can be opened on them.
 	 */
 	gt->oa.num_oa_units = num_oa_units;
 	gt->oa.oa_unit = u;

drivers/gpu/drm/xe/xe_observation.c

@@ -0,0 +1,93 @@
+// SPDX-License-Identifier: MIT
+/*
+ * Copyright © 2023-2024 Intel Corporation
+ */
+
+#include <linux/errno.h>
+#include <linux/sysctl.h>
+
+#include <drm/xe_drm.h>
+
+#include "xe_oa.h"
+#include "xe_observation.h"
+
+u32 xe_observation_paranoid = true;
+static struct ctl_table_header *sysctl_header;
+
+static int xe_oa_ioctl(struct drm_device *dev, struct drm_xe_observation_param *arg,
+		       struct drm_file *file)
+{
+	switch (arg->observation_op) {
+	case DRM_XE_OBSERVATION_OP_STREAM_OPEN:
+		return xe_oa_stream_open_ioctl(dev, arg->param, file);
+	case DRM_XE_OBSERVATION_OP_ADD_CONFIG:
+		return xe_oa_add_config_ioctl(dev, arg->param, file);
+	case DRM_XE_OBSERVATION_OP_REMOVE_CONFIG:
+		return xe_oa_remove_config_ioctl(dev, arg->param, file);
+	default:
+		return -EINVAL;
+	}
+}
+
+/**
+ * xe_observation_ioctl - The top level observation layer ioctl
+ * @dev: @drm_device
+ * @data: pointer to struct @drm_xe_observation_param
+ * @file: @drm_file
+ *
+ * The function is called for different observation streams types and
+ * allows execution of different operations supported by those stream
+ * types.
+ *
+ * Return: 0 on success or a negative error code on failure.
+ */
+int xe_observation_ioctl(struct drm_device *dev, void *data, struct drm_file *file)
+{
+	struct drm_xe_observation_param *arg = data;
+
+	if (arg->extensions)
+		return -EINVAL;
+
+	switch (arg->observation_type) {
+	case DRM_XE_OBSERVATION_TYPE_OA:
+		return xe_oa_ioctl(dev, arg, file);
+	default:
+		return -EINVAL;
+	}
+}
+
+static struct ctl_table observation_ctl_table[] = {
+	{
+	 .procname = "observation_paranoid",
+	 .data = &xe_observation_paranoid,
+	 .maxlen = sizeof(xe_observation_paranoid),
+	 .mode = 0644,
+	 .proc_handler = proc_dointvec_minmax,
+	 .extra1 = SYSCTL_ZERO,
+	 .extra2 = SYSCTL_ONE,
+	 },
+	{}
+};
+
+/**
+ * xe_observation_sysctl_register - Register xe_observation_paranoid sysctl
+ *
+ * Normally only superuser/root can access observation stream
+ * data. However, superuser can set xe_observation_paranoid sysctl to 0 to
+ * allow non-privileged users to also access observation data.
+ *
+ * Return: always returns 0
+ */
+int xe_observation_sysctl_register(void)
+{
+	sysctl_header = register_sysctl("dev/xe", observation_ctl_table);
+	return 0;
+}
+
+/**
+ * xe_observation_sysctl_unregister - Unregister xe_observation_paranoid sysctl
+ */
+void xe_observation_sysctl_unregister(void)
+{
+	unregister_sysctl_table(sysctl_header);
+}

drivers/gpu/drm/xe/xe_observation.h

@@ -0,0 +1,20 @@
+/* SPDX-License-Identifier: MIT */
+/*
+ * Copyright © 2023-2024 Intel Corporation
+ */
+
+#ifndef _XE_OBSERVATION_H_
+#define _XE_OBSERVATION_H_
+
+#include <linux/types.h>
+
+struct drm_device;
+struct drm_file;
+
+extern u32 xe_observation_paranoid;
+
+int xe_observation_ioctl(struct drm_device *dev, void *data, struct drm_file *file);
+int xe_observation_sysctl_register(void);
+void xe_observation_sysctl_unregister(void);
+
+#endif