On 2026-09-22 11:09, Timur Kristóf wrote:
On Monday, September 21, 2026 10:03:02 PM Central European Summer Time James
Zhu wrote:
Add the DRM_AMDGPU_PROFILER ioctl number and its argument structures, the
UAPI for GPU performance monitoring features such as SPM (Stream
Performance Monitor).
struct drm_amdgpu_profiler_args carries an operation selector and a union
of per-operation parameters, currently AMDGPU_PROFILER_OP_GET_VER and
AMDGPU_PROFILER_OP_SPM. The SPM operations and the layout of the
destination buffer are described by struct drm_amdgpu_spm_args and
struct drm_amdgpu_spm_buffer_header.
The ioctl number and struct layout are frozen here. The implementation
lands in the rest of this series and the ioctl is not registered in
amdgpu_ioctls_kms[] until then, so this header change alone does not make
the interface reachable.
Signed-off-by: James Zhu<[email protected]>
Reviewed-by: Bing Ma<[email protected]>
Hi,
Can you guys please clarify why this is necessary and what the use case is?
Are we sure we want a uAPI for this? RADV has been using SPM from userspace
for many years now.
[JZ] current RADV SPM is for graphic engine. These patches are for
compute engine SPM.
Thanks!
James
Thanks & best regards,
Timur
---
include/uapi/drm/amdgpu_drm.h | 124 ++++++++++++++++++++++++++++++++++
1 file changed, 124 insertions(+)
diff --git a/include/uapi/drm/amdgpu_drm.h b/include/uapi/drm/amdgpu_drm.h
index 9e5fa6f53e59..285949d63eb6 100644
--- a/include/uapi/drm/amdgpu_drm.h
+++ b/include/uapi/drm/amdgpu_drm.h
@@ -60,6 +60,7 @@ extern "C" {
#define DRM_AMDGPU_GEM_LIST_HANDLES 0x19
#define DRM_AMDGPU_PROC_OPTIONS 0x1A
#define DRM_AMDGPU_TRAP 0x1B
+#define DRM_AMDGPU_PROFILER 0x1C
#define DRM_IOCTL_AMDGPU_GEM_CREATE DRM_IOWR(DRM_COMMAND_BASE +
DRM_AMDGPU_GEM_CREATE, union drm_amdgpu_gem_create) #define
DRM_IOCTL_AMDGPU_GEM_MMAP DRM_IOWR(DRM_COMMAND_BASE + DRM_AMDGPU_GEM_MMAP,
union drm_amdgpu_gem_mmap) @@ -83,6 +84,7 @@ extern "C" {
#define DRM_IOCTL_AMDGPU_GEM_LIST_HANDLES DRM_IOWR(DRM_COMMAND_BASE +
DRM_AMDGPU_GEM_LIST_HANDLES, struct drm_amdgpu_gem_list_handles) #define
DRM_IOCTL_AMDGPU_PROC_OPTIONS DRM_IOWR(DRM_COMMAND_BASE +
DRM_AMDGPU_PROC_OPTIONS, struct drm_amdgpu_proc_options) #define
DRM_IOCTL_AMDGPU_TRAP DRM_IOWR(DRM_COMMAND_BASE + DRM_AMDGPU_TRAP,
union
drm_amdgpu_trap) +#define
DRM_IOCTL_AMDGPU_PROFILER DRM_IOWR(DRM_COMMAND_BASE +
DRM_AMDGPU_PROFILER,
struct drm_amdgpu_profiler_args)
/**
* DOC: memory domains
@@ -1821,6 +1823,128 @@ struct drm_amdgpu_proc_options {
} kfd_sigbus_delay;
};
+/*
+ * Supported SPM (Stream Performance Monitor) Operations
+ */
+/**
+ * drm_amdgpu_spm_op - SPM ioctl operations
+ */
+enum drm_amdgpu_spm_op {
+ AMDGPU_SPM_OP_ACQUIRE = 1,
+ AMDGPU_SPM_OP_RELEASE,
+ AMDGPU_SPM_OP_SET_DEST_BUF
+};
+
+/**
+ * drm_amdgpu_spm_args - Arguments for SPM ioctl
+ *
+ * @dest_buf: [in] used for the address of the destination buffer
+ * in @AMDGPU_SPM_OP_SET_DEST_BUF
+ * @buf_size: [in] size of the destination buffer
+ * @op: [in] specifies the operation to perform
+ * @timeout: [in/out] timeout in milliseconds (in), amount of time left
+ * in the timeout window (out)
+ * @bytes_copied: [out] total amount of data that was copied to the
previous dest_buf + * @has_data_loss: [out] non-zero if data was lost (e.g.
due to ring buffer overflow), + * zero otherwise
+ * @reserved: must be zero for forward compatibility
+ *
+ * This ioctl performs different functions depending on the @op parameter.
+ *
+ * AMDGPU_SPM_OP_ACQUIRE
+ * ------------------------
+ *
+ * Acquires exclusive access of SPM on the specified XCP for the calling
process. + * This must be called before using AMDGPU_SPM_OP_SET_DEST_BUF.
+ *
+ * AMDGPU_SPM_OP_RELEASE
+ * ------------------------
+ *
+ * Releases exclusive access of SPM on the specified XCP for the calling
process, + * which allows another process to acquire it in the future.
+ *
+ * AMDGPU_SPM_OP_SET_DEST_BUF
+ * -----------------------------
+ *
+ * If @dest_buf is NULL, the destination buffer address is unset and
copying of counters + * is stopped.
+ *
+ * If @dest_buf is not NULL, it specifies the pointer to a new destination
buffer. + * @buf_size specifies the size of the buffer.
+ *
+ * If @timeout is non-0, the call will wait for up to @timeout ms for the
previous + * buffer to be filled. If the previous buffer is filled before
the timeout, @timeout + * is updated with the time remaining. If the
timeout is exceeded, the function + * copies any partial data available
into the previous user buffer and returns success. + * The amount of valid
data in the previous user buffer is indicated by @bytes_copied. + *
+ * If @timeout is 0, the function immediately replaces the previous
destination buffer + * without waiting for the previous buffer to be
filled. That means the previous buffer + * may only be partially filled,
and @bytes_copied will indicate how much data has been + * copied to it.
+ *
+ * If data was lost, e.g. due to a ring buffer overflow, @has_data_loss
will be non-0. + *
+ * Returns negative error code on failure, 0 on success.
+ */
+struct drm_amdgpu_spm_args {
+ __u64 dest_buf;
+ __u32 buf_size;
+ __u32 op;
+ __u32 timeout;
+ __u32 bytes_copied;
+ __u32 has_data_loss;
+ __u32 reserved[9]; /* must be zero; pads this struct to 64
bytes */
+};
+
+/**
+ * drm_amdgpu_spm_buffer_header - SPM Buffer header for
drm_amdgpu_spm_args->dest_buf + *
+ * @version: [out] SPM version (0-23: minor, 24-31: major)
+ * @bytes_copied: [out] Amount of data copied for this sub-block
+ * @has_data_loss: [out] Boolean indicating whether data was lost for this
sub-block + * (e.g. due to a ring-buffer overflow)
+ * @reserved: Reserved for future use, must be zero
+ *
+ * This header precedes the SPM data in the destination buffer. The
reserved + * field maintains 64-byte cache line alignment (32 bytes total).
+ */
+struct drm_amdgpu_spm_buffer_header {
+ __u32 version; /* 0-23: minor, 24-31: major */
+ __u32 bytes_copied;
+ __u32 has_data_loss;
+ __u32 reserved[5]; /* pad to 32 bytes (64-byte cache line / 2) */
+};
+
+/* Supported Profiler Operation */
+#define AMDGPU_PROFILER_OP_GET_VER 1 /* get profiler UAPI
version */
+#define AMDGPU_PROFILER_OP_SPM 2
+
+/*
+ * Profiler IOCTL
+ */
+/**
+ * struct drm_amdgpu_profiler_args - Profiler IOCTL arguments
+ * @op: Operation to perform (AMDGPU_PROFILER_OP_*)
+ * @pad: Must be zero for input validation
+ * @data: Operation-specific parameters (union)
+ *
+ * GET_VER operation:
+ * Returns the profiler UAPI version in @data.version as (MAJOR<<24) |
MINOR. + * Input: @data must be zero (reserved for forward compatibility).
+ *
+ * Design note: GET_VER is intentionally a parameter-free query returning
+ * the global profiler UAPI version.
+ */
+struct drm_amdgpu_profiler_args {
+ __u32 op; /*
AMDGPU_PROFILER_OP_* */
+ __u32 pad; /* must be zero */
+ union {
+ __u32 version; /* GET_VER: out
(MAJOR<<24) | MINOR */
+ struct drm_amdgpu_spm_args spm;
+ } data;
+};
+
#if defined(__cplusplus)
}
#endif
