Re: [PATCH v1 03/11] drm/ras: Introduce set-error-threshold

Tauro, Riana
2026-04-22T06:12:39Z

On 4/18/2026 2:46 AM, Raag Jadav wrote:
> Add set-error-threshold command support which allows setting threshold
> value of the error. Threshold in RAS context means the number of errors
> the hardware is expected to accumulate before it raises them to software.
> This is to have a fine grained control over error notifications that are
> raised by the hardware.
>
> Signed-off-by: Raag Jadav <raag.jadav@intel.com>
> ---
> Documentation/gpu/drm-ras.rst | 9 +++++
> Documentation/netlink/specs/drm_ras.yaml | 12 ++++++
> drivers/gpu/drm/drm_ras.c | 48 ++++++++++++++++++++++++
> drivers/gpu/drm/drm_ras_nl.c | 14 +++++++
> drivers/gpu/drm/drm_ras_nl.h | 2 +
> include/drm/drm_ras.h | 13 +++++++
> include/uapi/drm/drm_ras.h | 1 +
> 7 files changed, 99 insertions(+)
>
> diff --git a/Documentation/gpu/drm-ras.rst b/Documentation/gpu/drm-ras.rst
> index 6443dfd1677f..a819aa150604 100644
> --- a/Documentation/gpu/drm-ras.rst
> +++ b/Documentation/gpu/drm-ras.rst
> @@ -54,6 +54,8 @@ User space tools can:
> ``node-id`` and ``error-id`` as parameters.
> * Query specific error threshold value with the ``get-error-threshold`` command, using both
> ``node-id`` and ``error-id`` as parameters.
> +* Set specific error threshold value with the ``set-error-threshold`` command, using
> + ``node-id``, ``error-id`` and ``error-threshold`` as parameters.
>
> YAML-based Interface
> --------------------
> @@ -109,3 +111,10 @@ Example: Query threshold value of a given error
>
> sudo ynl --family drm_ras --do get-error-threshold --json '{"node-id":0, "error-id":1}'
> {'error-id': 1, 'error-name': 'error_name1', 'error-threshold': 0}
> +
> +Example: Set threshold value of a given error
> +
> +.. code-block:: bash
> +
> + sudo ynl --family drm_ras --do set-error-threshold --json '{"node-id":0, "error-id":1, "error-threshold":8}'
> + None
> diff --git a/Documentation/netlink/specs/drm_ras.yaml b/Documentation/netlink/specs/drm_ras.yaml
> index 95a939fb987d..09824309cdff 100644
> --- a/Documentation/netlink/specs/drm_ras.yaml
> +++ b/Documentation/netlink/specs/drm_ras.yaml
> @@ -150,3 +150,15 @@ operations:
> - error-id
> - error-name
> - error-threshold
> + -
> + name: set-error-threshold
> + doc: >-
> + Set threshold value of the error.
> + attribute-set: error-threshold-attrs
> + flags: [admin-perm]
> + do:
> + request:
> + attributes:
> + - node-id
> + - error-id
> + - error-threshold
> diff --git a/drivers/gpu/drm/drm_ras.c b/drivers/gpu/drm/drm_ras.c
> index d2d853d5d69c..e4ff6d87f824 100644
> --- a/drivers/gpu/drm/drm_ras.c
> +++ b/drivers/gpu/drm/drm_ras.c
> @@ -41,6 +41,9 @@
> * Userspace must provide Node ID and Error ID.
> * Returns the threshold value of a specific error.
> *
> + * 4. SET_ERROR_THRESHOLD: Set threshold value of the error.
> + * Userspace must provide Node ID, Error ID and Threshold value to be set.
> + *
> * Node registration:
> *
> * - drm_ras_node_register(): Registers a new node and assigns
> @@ -72,6 +75,8 @@
> * operation, fetching a counter value from a specific node.
> * - drm_ras_nl_get_error_threshold_doit(): Implements the GET_ERROR_THRESHOLD doit
> * operation, fetching the threshold value of a specific error.
> + * - drm_ras_nl_set_error_threshold_doit(): Implements the SET_ERROR_THRESHOLD doit
> + * operation, setting the threshold value of a specific error.
> */
>
> static DEFINE_XARRAY_ALLOC(drm_ras_xa);
> @@ -184,6 +189,21 @@ static int get_node_error_threshold(u32 node_id, u32 error_id,
> return node->query_error_threshold(node, error_id, name, value);
> }
>
> +static int set_node_error_threshold(u32 node_id, u32 error_id, u32 value)
> +{
> + struct drm_ras_node *node;
> +
> + node = xa_load(&drm_ras_xa, node_id);
> + if (!node || !node->set_error_threshold)
> + return -ENOENT;

Use -EOPNOTSUPP for absence of function

> +
> + if (error_id < node->error_counter_range.first ||
> + error_id > node->error_counter_range.last)
> + return -EINVAL;
> +
> + return node->set_error_threshold(node, error_id, value);
> +}
> +
> static int msg_reply_counter_value(struct sk_buff *msg, u32 error_id,
> const char *error_name, u32 value)
> {
> @@ -417,6 +437,34 @@ int drm_ras_nl_get_error_threshold_doit(struct sk_buff *skb,
> return doit_reply_threshold_value(info, node_id, error_id);
> }
>
> +/**
> + * drm_ras_nl_set_error_threshold_doit() - Set threshold value of the error
> + * @skb: Netlink message buffer
> + * @info: Generic Netlink info containing attributes of the request
> + *
> + * Extracts the node ID, error ID and threshold value from the netlink attributes
> + * and sets the threshold of the corresponding error.
> + *
> + * Return: 0 on success, or negative errno on failure.
> + */
> +int drm_ras_nl_set_error_threshold_doit(struct sk_buff *skb,
> + struct genl_info *info)
> +{
> + u32 node_id, error_id, value;
> +
> + if (!info->attrs ||
> + GENL_REQ_ATTR_CHECK(info, DRM_RAS_A_ERROR_THRESHOLD_ATTRS_NODE_ID) ||
> + GENL_REQ_ATTR_CHECK(info, DRM_RAS_A_ERROR_THRESHOLD_ATTRS_ERROR_ID) ||
> + GENL_REQ_ATTR_CHECK(info, DRM_RAS_A_ERROR_THRESHOLD_ATTRS_ERROR_THRESHOLD))
> + return -EINVAL;
> +
> + node_id = nla_get_u32(info->attrs[DRM_RAS_A_ERROR_THRESHOLD_ATTRS_NODE_ID]);
> + error_id = nla_get_u32(info->attrs[DRM_RAS_A_ERROR_THRESHOLD_ATTRS_ERROR_ID]);
> + value = nla_get_u32(info->attrs[DRM_RAS_A_ERROR_THRESHOLD_ATTRS_ERROR_THRESHOLD]);

do we need a check for max threshold here? Probably configured by drivers?
Or is it upto the driver to check? If its upto the driver, please add it
in the document

Thanks
Riana

> +
> + return set_node_error_threshold(node_id, error_id, value);
> +}
> +
> /**
> * drm_ras_node_register() - Register a new RAS node
> * @node: Node structure to register
> diff --git a/drivers/gpu/drm/drm_ras_nl.c b/drivers/gpu/drm/drm_ras_nl.c
> index 48e231734f4d..8b202d773dac 100644
> --- a/drivers/gpu/drm/drm_ras_nl.c
> +++ b/drivers/gpu/drm/drm_ras_nl.c
> @@ -28,6 +28,13 @@ static const struct nla_policy drm_ras_get_error_threshold_nl_policy[DRM_RAS_A_E
> [DRM_RAS_A_ERROR_THRESHOLD_ATTRS_ERROR_ID] = { .type = NLA_U32, },
> };
>
> +/* DRM_RAS_CMD_SET_ERROR_THRESHOLD - do */
> +static const struct nla_policy drm_ras_set_error_threshold_nl_policy[DRM_RAS_A_ERROR_THRESHOLD_ATTRS_ERROR_THRESHOLD + 1] = {
> + [DRM_RAS_A_ERROR_THRESHOLD_ATTRS_NODE_ID] = { .type = NLA_U32, },
> + [DRM_RAS_A_ERROR_THRESHOLD_ATTRS_ERROR_ID] = { .type = NLA_U32, },
> + [DRM_RAS_A_ERROR_THRESHOLD_ATTRS_ERROR_THRESHOLD] = { .type = NLA_U32, },
> +};
> +
> /* Ops table for drm_ras */
> static const struct genl_split_ops drm_ras_nl_ops[] = {
> {
> @@ -56,6 +63,13 @@ static const struct genl_split_ops drm_ras_nl_ops[] = {
> .maxattr = DRM_RAS_A_ERROR_THRESHOLD_ATTRS_ERROR_ID,
> .flags = GENL_ADMIN_PERM | GENL_CMD_CAP_DO,
> },
> + {
> + .cmd = DRM_RAS_CMD_SET_ERROR_THRESHOLD,
> + .doit = drm_ras_nl_set_error_threshold_doit,
> + .policy = drm_ras_set_error_threshold_nl_policy,
> + .maxattr = DRM_RAS_A_ERROR_THRESHOLD_ATTRS_ERROR_THRESHOLD,
> + .flags = GENL_ADMIN_PERM | GENL_CMD_CAP_DO,
> + },
> };
>
> struct genl_family drm_ras_nl_family __ro_after_init = {
> diff --git a/drivers/gpu/drm/drm_ras_nl.h b/drivers/gpu/drm/drm_ras_nl.h
> index 540fe22e2312..9db7f5d00201 100644
> --- a/drivers/gpu/drm/drm_ras_nl.h
> +++ b/drivers/gpu/drm/drm_ras_nl.h
> @@ -20,6 +20,8 @@ int drm_ras_nl_get_error_counter_dumpit(struct sk_buff *skb,
> struct netlink_callback *cb);
> int drm_ras_nl_get_error_threshold_doit(struct sk_buff *skb,
> struct genl_info *info);
> +int drm_ras_nl_set_error_threshold_doit(struct sk_buff *skb,
> + struct genl_info *info);
>
> extern struct genl_family drm_ras_nl_family;
>
> diff --git a/include/drm/drm_ras.h b/include/drm/drm_ras.h
> index 50cee70bd065..7a69821b8b78 100644
> --- a/include/drm/drm_ras.h
> +++ b/include/drm/drm_ras.h
> @@ -71,6 +71,19 @@ struct drm_ras_node {
> */
> int (*query_error_threshold)(struct drm_ras_node *node, u32 error_id,
> const char **name, u32 *val);
> + /**
> + * @set_error_threshold:
> + *
> + * This callback is used by drm-ras to set threshold value of a specific
> + * error.
> + *
> + * Driver should expect set_error_threshold() to be called with error_id
> + * from `error_counter_range.first` to `error_counter_range.last`.
> + *
> + * Returns: 0 on success, negative error code on failure.
> + */
> + int (*set_error_threshold)(struct drm_ras_node *node, u32 error_id,
> + u32 val);
>
> /** @priv: Driver private data */
> void *priv;
> diff --git a/include/uapi/drm/drm_ras.h b/include/uapi/drm/drm_ras.h
> index 49c5ca497d73..8ff0311d0d63 100644
> --- a/include/uapi/drm/drm_ras.h
> +++ b/include/uapi/drm/drm_ras.h
> @@ -52,6 +52,7 @@ enum {
> DRM_RAS_CMD_LIST_NODES = 1,
> DRM_RAS_CMD_GET_ERROR_COUNTER,
> DRM_RAS_CMD_GET_ERROR_THRESHOLD,
> + DRM_RAS_CMD_SET_ERROR_THRESHOLD,
>
> __DRM_RAS_CMD_MAX,
> DRM_RAS_CMD_MAX = (__DRM_RAS_CMD_MAX - 1)