diff --git a/drivers/gpu/drm/panthor/panthor_device.h b/drivers/gpu/drm/panthor/panthor_device.h
index 818c4d96d448..3fa0882fe81b 100644
--- a/drivers/gpu/drm/panthor/panthor_device.h
+++ b/drivers/gpu/drm/panthor/panthor_device.h
@@ -225,6 +225,9 @@ struct panthor_file {
 	/** @ptdev: Device attached to this file. */
 	struct panthor_device *ptdev;
 
+	/** @drm_file: Corresponding drm_file */
+	struct drm_file *drm_file;
+
 	/** @vms: VM pool attached to this file. */
 	struct panthor_vm_pool *vms;
 
diff --git a/drivers/gpu/drm/panthor/panthor_drv.c b/drivers/gpu/drm/panthor/panthor_drv.c
index 9d2b716cca45..4c1381320859 100644
--- a/drivers/gpu/drm/panthor/panthor_drv.c
+++ b/drivers/gpu/drm/panthor/panthor_drv.c
@@ -1356,6 +1356,7 @@ panthor_open(struct drm_device *ddev, struct drm_file *file)
 	}
 
 	pfile->ptdev = ptdev;
+	pfile->drm_file = file;
 
 	ret = panthor_vm_pool_create(pfile);
 	if (ret)
diff --git a/drivers/gpu/drm/panthor/panthor_perf.c b/drivers/gpu/drm/panthor/panthor_perf.c
index 7c59c8642b7c..62c27be4ca8b 100644
--- a/drivers/gpu/drm/panthor/panthor_perf.c
+++ b/drivers/gpu/drm/panthor/panthor_perf.c
@@ -2,13 +2,177 @@
 /* Copyright 2023 Collabora Ltd */
 /* Copyright 2025 Arm ltd. */
 
-#include <linux/bitops.h>
+#include <drm/drm_gem.h>
 #include <drm/panthor_drm.h>
+#include <linux/bitops.h>
+#include <linux/circ_buf.h>
 
 #include "panthor_device.h"
 #include "panthor_fw.h"
 #include "panthor_perf.h"
 
+/**
+ * PANTHOR_PERF_EM_BITS - Number of bits in a user-facing enable mask. This must correspond
+ *                        to the maximum number of counters available for selection on the newest
+ *                        Mali GPUs (128 as of the Mali-Gx15).
+ */
+#define PANTHOR_PERF_EM_BITS (BITS_PER_TYPE(u64) * 2)
+
+enum panthor_perf_session_state {
+	/** @PANTHOR_PERF_SESSION_ACTIVE: The session is active and can be used for sampling. */
+	PANTHOR_PERF_SESSION_ACTIVE = 0,
+
+	/**
+	 * @PANTHOR_PERF_SESSION_OVERFLOW: The session encountered an overflow in one of the
+	 *                                 counters during the last sampling period. This flag
+	 *                                 gets propagated as part of samples emitted for this
+	 *                                 session, to ensure the userspace client can gracefully
+	 *                                 handle this data corruption.
+	 */
+	PANTHOR_PERF_SESSION_OVERFLOW,
+
+	/* Must be last */
+	PANTHOR_PERF_SESSION_MAX,
+};
+
+struct panthor_perf_enable_masks {
+	/**
+	 * @mask: Array of bitmasks indicating the counters userspace requested, where
+	 *        one bit represents a single counter. Used to build the firmware configuration
+	 *        and ensure that userspace clients obtain only the counters they requested.
+	 */
+	unsigned long mask[DRM_PANTHOR_PERF_BLOCK_MAX][BITS_TO_LONGS(PANTHOR_PERF_EM_BITS)];
+};
+
+struct panthor_perf_counter_block {
+	struct drm_panthor_perf_block_header header;
+	u64 counters[];
+};
+
+/**
+ * enum session_sample_type - Enum of the types of samples a session can request.
+ */
+enum session_sample_type {
+	/** @SAMPLE_TYPE_NONE: A sample has not been requested by this session. */
+	SAMPLE_TYPE_NONE,
+
+	/** @SAMPLE_TYPE_INITIAL: An initial sample has been requested by this session. */
+	SAMPLE_TYPE_INITIAL,
+
+	/** @SAMPLE_TYPE_REGULAR: A regular sample has been requested by this session. */
+	SAMPLE_TYPE_REGULAR,
+};
+
+struct panthor_perf_session {
+	DECLARE_BITMAP(state, PANTHOR_PERF_SESSION_MAX);
+
+	/**
+	 * @pending_sample_request: The type of sample request that is currently pending:
+	 *                          - when a sample is not requested, the data should be accumulated
+	 *                            into the next slot of its ring buffer, but the extract index
+	 *                            should not be updated, and the user-space session must
+	 *                            not be signaled.
+	 *                          - when an initial sample is requested, the data must not be
+	 *                            emitted into the target ring buffer and the userspace client
+	 *                            must not be notified.
+	 *                          - when a regular sample is requested, the data must be emitted
+	 *                            into the target ring buffer, and the userspace client must
+	 *                            be signalled.
+	 */
+	enum session_sample_type pending_sample_request;
+
+	/**
+	 * @user_sample_size: The size of a single sample as exposed to userspace. For the sake of
+	 *                    simplicity, the current implementation exposes the same structure
+	 *                    as provided by firmware, after annotating the sample and the blocks,
+	 *                    and zero-extending the counters themselves (to account for in-kernel
+	 *                    accumulation).
+	 *
+	 *                    This may also allow further memory-optimizations of compressing the
+	 *                    sample to provide only requested blocks, if deemed to be worth the
+	 *                    additional complexity.
+	 */
+	size_t user_sample_size;
+
+	/**
+	 * @accum_idx: The last insert index indicates whether the current sample
+	 *                   needs zeroing before accumulation. This is used to disambiguate
+	 *                   between accumulating into an intermediate slot in the user ring buffer
+	 *                   and zero-ing the buffer before copying data over.
+	 */
+	u32 accum_idx;
+
+	/**
+	 * @sample_freq_ns: Period between subsequent sample requests. Zero indicates that
+	 *                  userspace will be responsible for requesting samples.
+	 */
+	u64 sample_freq_ns;
+
+	/** @sample_start_ns: Sample request time, obtained from a monotonic raw clock. */
+	u64 sample_start_ns;
+
+	/**
+	 * @user_data: Opaque handle passed in when starting a session, requesting a sample (for
+	 *             manual sampling sessions only) and when stopping a session. This handle
+	 *             allows the disambiguation of a sample in the ringbuffer.
+	 */
+	u64 user_data;
+
+	/**
+	 * @eventfd: Event file descriptor context used to signal userspace of a new sample
+	 *           being emitted.
+	 */
+	struct eventfd_ctx *eventfd;
+
+	/**
+	 * @enabled_counters: This session's requested counters. Note that these cannot change
+	 *                    for the lifetime of the session.
+	 */
+	struct panthor_perf_enable_masks *enabled_counters;
+
+	/** @ringbuf_slots: Slots in the user-facing ringbuffer. */
+	size_t ringbuf_slots;
+
+	/** @ring_buf: BO for the userspace ringbuffer. */
+	struct drm_gem_object *ring_buf;
+
+	/**
+	 * @control_buf: BO for the insert and extract indices.
+	 */
+	struct drm_gem_object *control_buf;
+
+	/** @control: The mapped insert and extract indices. */
+	struct drm_panthor_perf_ringbuf_control *control;
+
+	/** @samples: The mapping of the @ring_buf into the kernel's VA space. */
+	u8 *samples;
+
+	/**
+	 * @pending: The list node used by the sampler to track the sessions that have not yet
+	 *           received a sample.
+	 */
+	struct list_head pending;
+
+	/**
+	 * @sessions: The list node used by the sampler to track the sessions waiting for a sample.
+	 */
+	struct list_head sessions;
+
+	/**
+	 * @pfile: The panthor file which was used to create a session, used for the postclose
+	 *         handling and to prevent a misconfigured userspace from closing unrelated
+	 *         sessions.
+	 */
+	struct panthor_file *pfile;
+
+	/**
+	 * @ref: Session reference count. The sample delivery to userspace is asynchronous, meaning
+	 *       the lifetime of the session must extend at least until the sample is exposed to
+	 *       userspace.
+	 */
+	struct kref ref;
+};
+
 struct panthor_perf {
 	/** @next_session: The ID of the next session. */
 	u32 next_session;
@@ -51,6 +215,118 @@ static void panthor_perf_info_init(struct panthor_device *ptdev)
 	perf_info->shader_blocks = hweight64(ptdev->gpu_info.shader_present);
 }
 
+static struct panthor_perf_enable_masks *panthor_perf_create_em(struct drm_panthor_perf_cmd_setup
+		*setup_args)
+{
+	struct panthor_perf_enable_masks *em = kmalloc(sizeof(*em), GFP_KERNEL);
+	if (IS_ERR_OR_NULL(em))
+		return em;
+
+	bitmap_from_arr64(em->mask[DRM_PANTHOR_PERF_BLOCK_FW],
+			setup_args->fw_enable_mask, PANTHOR_PERF_EM_BITS);
+	bitmap_from_arr64(em->mask[DRM_PANTHOR_PERF_BLOCK_CSHW],
+			setup_args->cshw_enable_mask, PANTHOR_PERF_EM_BITS);
+	bitmap_from_arr64(em->mask[DRM_PANTHOR_PERF_BLOCK_TILER],
+			setup_args->tiler_enable_mask, PANTHOR_PERF_EM_BITS);
+	bitmap_from_arr64(em->mask[DRM_PANTHOR_PERF_BLOCK_MEMSYS],
+			setup_args->memsys_enable_mask, PANTHOR_PERF_EM_BITS);
+	bitmap_from_arr64(em->mask[DRM_PANTHOR_PERF_BLOCK_SHADER],
+			setup_args->shader_enable_mask, PANTHOR_PERF_EM_BITS);
+
+	return em;
+}
+
+static size_t get_annotated_block_size(size_t counters_per_block)
+{
+	return struct_size_t(struct panthor_perf_counter_block, counters, counters_per_block);
+}
+
+static u64 session_read_extract_idx(struct panthor_perf_session *session)
+{
+	/* Userspace will update their own extract index to indicate that a sample is consumed
+	 * from the ringbuffer, and we must ensure we read the latest value.
+	 */
+	return smp_load_acquire(&session->control->extract_idx);
+}
+
+static u64 session_read_insert_idx(struct panthor_perf_session *session)
+{
+	return session->control->insert_idx;
+}
+
+static void session_get(struct panthor_perf_session *session)
+{
+	kref_get(&session->ref);
+}
+
+static void session_free(struct kref *ref)
+{
+	struct panthor_perf_session *session = container_of(ref, typeof(*session), ref);
+
+	if (session->samples && session->ring_buf) {
+		struct iosys_map map = IOSYS_MAP_INIT_VADDR(session->samples);
+
+		drm_gem_vunmap_unlocked(session->ring_buf, &map);
+		drm_gem_object_put(session->ring_buf);
+	}
+
+	if (session->control && session->control_buf) {
+		struct iosys_map map = IOSYS_MAP_INIT_VADDR(session->control);
+
+		drm_gem_vunmap_unlocked(session->control_buf, &map);
+		drm_gem_object_put(session->control_buf);
+	}
+
+	eventfd_ctx_put(session->eventfd);
+
+	kfree(session);
+}
+
+static void session_put(struct panthor_perf_session *session)
+{
+	kref_put(&session->ref, session_free);
+}
+
+/**
+ * session_find - Find a session associated with the given session ID and
+ *                panthor_file.
+ * @pfile: Panthor file.
+ * @perf: Panthor perf.
+ * @sid: Session ID.
+ *
+ * The reference count of a valid session is increased to ensure it does not disappear
+ * in the window between the XA lock being dropped and the internal session functions
+ * being called.
+ *
+ * Return: valid session pointer or an ERR_PTR.
+ */
+static struct panthor_perf_session *session_find(struct panthor_file *pfile,
+		struct panthor_perf *perf, u32 sid)
+{
+	struct panthor_perf_session *session;
+
+	if (!perf)
+		return ERR_PTR(-EINVAL);
+
+	xa_lock(&perf->sessions);
+	session = xa_load(&perf->sessions, sid);
+
+	if (!session || xa_is_err(session)) {
+		xa_unlock(&perf->sessions);
+		return ERR_PTR(-EBADF);
+	}
+
+	if (session->pfile != pfile) {
+		xa_unlock(&perf->sessions);
+		return ERR_PTR(-EINVAL);
+	}
+
+	session_get(session);
+	xa_unlock(&perf->sessions);
+
+	return session;
+}
+
 /**
  * panthor_perf_init - Initialize the performance counter subsystem.
  * @ptdev: Panthor device
@@ -88,6 +364,421 @@ int panthor_perf_init(struct panthor_device *ptdev)
 	return ret;
 }
 
+static size_t session_get_user_sample_size(const struct drm_panthor_perf_info *const info)
+{
+	const size_t block_size = get_annotated_block_size(info->counters_per_block);
+	const size_t block_nr = info->cshw_blocks + info->fw_blocks +
+		info->tiler_blocks + info->memsys_blocks + info->shader_blocks;
+
+	return sizeof(struct drm_panthor_perf_sample_header) + (block_size * block_nr);
+}
+
+static int session_validate_set(u8 set)
+{
+	if (set > DRM_PANTHOR_PERF_SET_TERTIARY)
+		return -EINVAL;
+
+	if (set == DRM_PANTHOR_PERF_SET_PRIMARY)
+		return 0;
+
+	if (set > DRM_PANTHOR_PERF_SET_PRIMARY)
+		return capable(CAP_PERFMON) ? 0 : -EACCES;
+
+	return -EINVAL;
+}
+
+/**
+ * panthor_perf_session_setup - Create a user-visible session.
+ *
+ * @ptdev: Handle to the panthor device.
+ * @perf: Handle to the perf control structure.
+ * @setup_args: Setup arguments passed in via ioctl.
+ * @pfile: Panthor file associated with the request.
+ *
+ * Creates a new session associated with the session ID returned. When initialized, the
+ * session must explicitly request sampling to start with a successive call to PERF_CONTROL.START.
+ *
+ * Return: non-negative session identifier on success or negative error code on failure.
+ */
+int panthor_perf_session_setup(struct panthor_device *ptdev, struct panthor_perf *perf,
+		struct drm_panthor_perf_cmd_setup *setup_args,
+		struct panthor_file *pfile)
+{
+	struct panthor_perf_session *session;
+	struct drm_gem_object *ringbuffer;
+	struct drm_gem_object *control;
+	const size_t slots = setup_args->sample_slots;
+	struct panthor_perf_enable_masks *em;
+	struct iosys_map rb_map, ctrl_map;
+	size_t user_sample_size;
+	int session_id;
+	int ret;
+
+	ret = session_validate_set(setup_args->block_set);
+	if (ret) {
+		drm_err(&ptdev->base, "Did not meet requirements for set %d\n",
+				setup_args->block_set);
+		return ret;
+	}
+
+	session = kzalloc(sizeof(*session), GFP_KERNEL);
+	if (ZERO_OR_NULL_PTR(session))
+		return -ENOMEM;
+
+	ringbuffer = drm_gem_object_lookup(pfile->drm_file, setup_args->ringbuf_handle);
+	if (!ringbuffer) {
+		drm_err(&ptdev->base, "Could not find handle %d!\n", setup_args->ringbuf_handle);
+		ret = -EINVAL;
+		goto cleanup_session;
+	}
+
+	control = drm_gem_object_lookup(pfile->drm_file, setup_args->control_handle);
+	if (!control) {
+		drm_err(&ptdev->base, "Could not find handle %d!\n", setup_args->control_handle);
+		ret = -EINVAL;
+		goto cleanup_ringbuf;
+	}
+
+	user_sample_size = session_get_user_sample_size(&ptdev->perf_info) * slots;
+
+	if (ringbuffer->size != PFN_ALIGN(user_sample_size)) {
+		drm_err(&ptdev->base, "Incorrect ringbuffer size from userspace: user %zu vs kernel %lu\n",
+				ringbuffer->size, PFN_ALIGN(user_sample_size));
+		ret = -ENOMEM;
+		goto cleanup_control;
+	}
+
+	ret = drm_gem_vmap_unlocked(ringbuffer, &rb_map);
+	if (ret)
+		goto cleanup_control;
+
+	ret = drm_gem_vmap_unlocked(control, &ctrl_map);
+	if (ret)
+		goto cleanup_ring_map;
+
+	session->eventfd = eventfd_ctx_fdget(setup_args->fd);
+	if (IS_ERR(session->eventfd)) {
+		drm_err(&ptdev->base, "Invalid eventfd %d!\n", setup_args->fd);
+		ret = PTR_ERR_OR_ZERO(session->eventfd) ?: -EINVAL;
+		goto cleanup_control_map;
+	}
+
+	em = panthor_perf_create_em(setup_args);
+	if (IS_ERR_OR_NULL(em)) {
+		ret = -ENOMEM;
+		goto cleanup_eventfd;
+	}
+
+	INIT_LIST_HEAD(&session->sessions);
+	INIT_LIST_HEAD(&session->pending);
+
+	session->control = ctrl_map.vaddr;
+	*session->control = (struct drm_panthor_perf_ringbuf_control) { 0 };
+
+	session->samples = rb_map.vaddr;
+
+	/* TODO This will need validation when we support periodic sampling sessions */
+	if (setup_args->sample_freq_ns) {
+		ret = -EOPNOTSUPP;
+		goto cleanup_em;
+	}
+
+	ret = xa_alloc_cyclic(&perf->sessions, &session_id, session, perf->session_range,
+			&perf->next_session, GFP_KERNEL);
+	if (ret < 0) {
+		drm_err(&ptdev->base, "System session limit exceeded.\n");
+		ret = -EBUSY;
+		goto cleanup_em;
+	}
+
+	kref_init(&session->ref);
+	session->enabled_counters = em;
+
+	session->sample_freq_ns = setup_args->sample_freq_ns;
+	session->user_sample_size = user_sample_size;
+	session->ring_buf = ringbuffer;
+	session->ringbuf_slots = slots;
+	session->control_buf = control;
+	session->pfile = pfile;
+	session->accum_idx = U32_MAX;
+
+	return session_id;
+
+cleanup_em:
+	kfree(em);
+
+cleanup_eventfd:
+	eventfd_ctx_put(session->eventfd);
+
+cleanup_control_map:
+	drm_gem_vunmap_unlocked(control, &ctrl_map);
+
+cleanup_ring_map:
+	drm_gem_vunmap_unlocked(ringbuffer, &rb_map);
+
+cleanup_control:
+	drm_gem_object_put(control);
+
+cleanup_ringbuf:
+	drm_gem_object_put(ringbuffer);
+
+cleanup_session:
+	kfree(session);
+
+	return ret;
+}
+
+static int session_stop(struct panthor_perf *perf, struct panthor_perf_session *session,
+		u64 user_data)
+{
+	if (!test_bit(PANTHOR_PERF_SESSION_ACTIVE, session->state))
+		return 0;
+
+	const u32 extract_idx = session_read_extract_idx(session);
+	const u32 insert_idx = session_read_insert_idx(session);
+
+	/* Must have at least one slot remaining in the ringbuffer to sample. */
+	if (WARN_ON_ONCE(!CIRC_SPACE_TO_END(insert_idx, extract_idx, session->ringbuf_slots)))
+		return -EBUSY;
+
+	session->user_data = user_data;
+
+	clear_bit(PANTHOR_PERF_SESSION_ACTIVE, session->state);
+
+	/* TODO Calls to the FW interface will go here in later patches. */
+	return 0;
+}
+
+static int session_start(struct panthor_perf *perf, struct panthor_perf_session *session,
+		u64 user_data)
+{
+	if (test_bit(PANTHOR_PERF_SESSION_ACTIVE, session->state))
+		return 0;
+
+	set_bit(PANTHOR_PERF_SESSION_ACTIVE, session->state);
+
+	/*
+	 * For manual sampling sessions, a start command does not correspond to a sample,
+	 * and so the user data gets discarded.
+	 */
+	if (session->sample_freq_ns)
+		session->user_data = user_data;
+
+	/* TODO Calls to the FW interface will go here in later patches. */
+	return 0;
+}
+
+static int session_sample(struct panthor_perf *perf, struct panthor_perf_session *session,
+		u64 user_data)
+{
+	if (!test_bit(PANTHOR_PERF_SESSION_ACTIVE, session->state))
+		return 0;
+
+	const u32 extract_idx = session_read_extract_idx(session);
+	const u32 insert_idx = session_read_insert_idx(session);
+
+	/* Manual sampling for periodic sessions is forbidden. */
+	if (session->sample_freq_ns)
+		return -EINVAL;
+
+	/*
+	 * Must have at least two slots remaining in the ringbuffer to sample: one for
+	 * the current sample, and one for a stop sample, since a stop command should
+	 * always be acknowledged by taking a final sample and stopping the session.
+	 */
+	if (CIRC_SPACE_TO_END(insert_idx, extract_idx, session->ringbuf_slots) < 2)
+		return -EBUSY;
+
+	session->sample_start_ns = ktime_get_raw_ns();
+	session->user_data = user_data;
+
+	return 0;
+}
+
+static int session_destroy(struct panthor_perf *perf, struct panthor_perf_session *session)
+{
+	session_put(session);
+
+	return 0;
+}
+
+static int session_teardown(struct panthor_perf *perf, struct panthor_perf_session *session)
+{
+	if (test_bit(PANTHOR_PERF_SESSION_ACTIVE, session->state))
+		return -EINVAL;
+
+	if (READ_ONCE(session->pending_sample_request) == SAMPLE_TYPE_NONE)
+		return -EBUSY;
+
+	return session_destroy(perf, session);
+}
+
+/**
+ * panthor_perf_session_teardown - Teardown the session associated with the @sid.
+ * @pfile: Open panthor file.
+ * @perf: Handle to the perf control structure.
+ * @sid: Session identifier.
+ *
+ * Destroys a stopped session where the last sample has been explicitly consumed
+ * or discarded. Active sessions will be ignored.
+ *
+ * Return: 0 on success, negative error code on failure.
+ */
+int panthor_perf_session_teardown(struct panthor_file *pfile, struct panthor_perf *perf, u32 sid)
+{
+	int err;
+	struct panthor_perf_session *session;
+
+	xa_lock(&perf->sessions);
+	session = __xa_store(&perf->sessions, sid, NULL, GFP_KERNEL);
+
+	if (xa_is_err(session)) {
+		err = xa_err(session);
+		goto restore;
+	}
+
+	if (session->pfile != pfile) {
+		err = -EINVAL;
+		goto restore;
+	}
+
+	session_get(session);
+	xa_unlock(&perf->sessions);
+
+	err = session_teardown(perf, session);
+
+	session_put(session);
+
+	return err;
+
+restore:
+	__xa_store(&perf->sessions, sid, session, GFP_KERNEL);
+	xa_unlock(&perf->sessions);
+
+	return err;
+}
+
+/**
+ * panthor_perf_session_start - Start sampling on a stopped session.
+ * @pfile: Open panthor file.
+ * @perf: Handle to the panthor perf control structure.
+ * @sid: Session identifier for the desired session.
+ * @user_data: An opaque value passed in from userspace.
+ *
+ * A session counts as stopped when it is created or when it is explicitly stopped after being
+ * started. Starting an active session is treated as a no-op.
+ *
+ * The @user_data parameter will be associated with all subsequent samples for a periodic
+ * sampling session and will be ignored for manual sampling ones in favor of the user data
+ * passed in the PERF_CONTROL.SAMPLE ioctl call.
+ *
+ * Return: 0 on success, negative error code on failure.
+ */
+int panthor_perf_session_start(struct panthor_file *pfile, struct panthor_perf *perf,
+		u32 sid, u64 user_data)
+{
+	struct panthor_perf_session *session = session_find(pfile, perf, sid);
+	int err;
+
+	if (IS_ERR_OR_NULL(session))
+		return IS_ERR(session) ? PTR_ERR(session) : -EINVAL;
+
+	err = session_start(perf, session, user_data);
+
+	session_put(session);
+
+	return err;
+}
+
+/**
+ * panthor_perf_session_stop - Stop sampling on an active session.
+ * @pfile: Open panthor file.
+ * @perf: Handle to the panthor perf control structure.
+ * @sid: Session identifier for the desired session.
+ * @user_data: An opaque value passed in from userspace.
+ *
+ * A session counts as active when it has been explicitly started via the PERF_CONTROL.START
+ * ioctl. Stopping a stopped session is treated as a no-op.
+ *
+ * To ensure data is not lost when sampling is stopping, there must always be at least one slot
+ * available for the final automatic sample, and the stop command will be rejected if there is not.
+ *
+ * The @user_data will always be associated with the final sample.
+ *
+ * Return: 0 on success, negative error code on failure.
+ */
+int panthor_perf_session_stop(struct panthor_file *pfile, struct panthor_perf *perf,
+		u32 sid, u64 user_data)
+{
+	struct panthor_perf_session *session = session_find(pfile, perf, sid);
+	int err;
+
+	if (IS_ERR_OR_NULL(session))
+		return IS_ERR(session) ? PTR_ERR(session) : -EINVAL;
+
+	err = session_stop(perf, session, user_data);
+
+	session_put(session);
+
+	return err;
+}
+
+/**
+ * panthor_perf_session_sample - Request a sample on a manual sampling session.
+ * @pfile: Open panthor file.
+ * @perf: Handle to the panthor perf control structure.
+ * @sid: Session identifier for the desired session.
+ * @user_data: An opaque value passed in from userspace.
+ *
+ * Only an active manual sampler is permitted to request samples directly. Failing to meet either
+ * of these conditions will cause the sampling request to be rejected. Requesting a manual sample
+ * with a full ringbuffer will see the request being rejected.
+ *
+ * The @user_data will always be unambiguously associated one-to-one with the resultant sample.
+ *
+ * Return: 0 on success, negative error code on failure.
+ */
+int panthor_perf_session_sample(struct panthor_file *pfile, struct panthor_perf *perf,
+		u32 sid, u64 user_data)
+{
+	struct panthor_perf_session *session = session_find(pfile, perf, sid);
+	int err;
+
+	if (IS_ERR_OR_NULL(session))
+		return IS_ERR(session) ? PTR_ERR(session) : -EINVAL;
+
+	err = session_sample(perf, session, user_data);
+
+	session_put(session);
+
+	return err;
+}
+
+/**
+ * panthor_perf_session_destroy - Destroy a sampling session associated with the @pfile.
+ * @perf: Handle to the panthor perf control structure.
+ * @pfile: The file being closed.
+ *
+ * Must be called when the corresponding userspace process is destroyed and cannot close its
+ * own sessions. As such, we offer no guarantees about data delivery.
+ */
+void panthor_perf_session_destroy(struct panthor_file *pfile, struct panthor_perf *perf)
+{
+	unsigned long sid;
+	struct panthor_perf_session *session;
+
+	if (!pfile || !perf)
+		return;
+
+	xa_for_each(&perf->sessions, sid, session)
+	{
+		if (session->pfile == pfile) {
+			session_destroy(perf, session);
+			xa_erase(&perf->sessions, sid);
+		}
+	}
+}
+
 /**
  * panthor_perf_unplug - Terminate the performance counter subsystem.
  * @ptdev: Panthor device.
@@ -103,8 +794,14 @@ void panthor_perf_unplug(struct panthor_device *ptdev)
 		return;
 
 	if (!xa_empty(&perf->sessions)) {
+		unsigned long sid;
+		struct panthor_perf_session *session;
+
 		drm_err(&ptdev->base,
 			"Performance counter sessions active when unplugging the driver!");
+
+		xa_for_each(&perf->sessions, sid, session)
+			session_destroy(perf, session);
 	}
 
 	xa_destroy(&perf->sessions);
diff --git a/drivers/gpu/drm/panthor/panthor_perf.h b/drivers/gpu/drm/panthor/panthor_perf.h
index e4805727b9e7..89d61cd1f017 100644
--- a/drivers/gpu/drm/panthor/panthor_perf.h
+++ b/drivers/gpu/drm/panthor/panthor_perf.h
@@ -7,10 +7,26 @@
 
 #include <linux/types.h>
 
+struct drm_panthor_perf_cmd_setup;
 struct panthor_device;
+struct panthor_file;
+struct panthor_perf;
 
 int panthor_perf_init(struct panthor_device *ptdev);
 void panthor_perf_unplug(struct panthor_device *ptdev);
 
+int panthor_perf_session_setup(struct panthor_device *ptdev, struct panthor_perf *perf,
+		struct drm_panthor_perf_cmd_setup *setup_args,
+		struct panthor_file *pfile);
+int panthor_perf_session_teardown(struct panthor_file *pfile, struct panthor_perf *perf,
+		u32 sid);
+int panthor_perf_session_start(struct panthor_file *pfile, struct panthor_perf *perf,
+		u32 sid, u64 user_data);
+int panthor_perf_session_stop(struct panthor_file *pfile, struct panthor_perf *perf,
+		u32 sid, u64 user_data);
+int panthor_perf_session_sample(struct panthor_file *pfile, struct panthor_perf *perf,
+		u32 sid, u64 user_data);
+void panthor_perf_session_destroy(struct panthor_file *pfile, struct panthor_perf *perf);
+
 #endif /* __PANTHOR_PERF_H__ */
 
