【代码】Mellanox驱动中rdma_cm建链被拒绝的原因有哪些？

宏定义

include/rdma/ib_cm.h

enum ib_cm_rej_reason {
	IB_CM_REJ_NO_QP				= 1,
	IB_CM_REJ_NO_EEC			= 2,
	IB_CM_REJ_NO_RESOURCES			= 3,
	IB_CM_REJ_TIMEOUT			= 4,
	IB_CM_REJ_UNSUPPORTED			= 5,
	IB_CM_REJ_INVALID_COMM_ID		= 6,
	IB_CM_REJ_INVALID_COMM_INSTANCE		= 7,
	IB_CM_REJ_INVALID_SERVICE_ID		= 8,
	IB_CM_REJ_INVALID_TRANSPORT_TYPE	= 9,
	IB_CM_REJ_STALE_CONN			= 10,
	IB_CM_REJ_RDC_NOT_EXIST			= 11,
	IB_CM_REJ_INVALID_GID			= 12,
	IB_CM_REJ_INVALID_LID			= 13,
	IB_CM_REJ_INVALID_SL			= 14,
	IB_CM_REJ_INVALID_TRAFFIC_CLASS		= 15,
	IB_CM_REJ_INVALID_HOP_LIMIT		= 16,
	IB_CM_REJ_INVALID_PACKET_RATE		= 17,
	IB_CM_REJ_INVALID_ALT_GID		= 18,
	IB_CM_REJ_INVALID_ALT_LID		= 19,
	IB_CM_REJ_INVALID_ALT_SL		= 20,
	IB_CM_REJ_INVALID_ALT_TRAFFIC_CLASS	= 21,
	IB_CM_REJ_INVALID_ALT_HOP_LIMIT		= 22,
	IB_CM_REJ_INVALID_ALT_PACKET_RATE	= 23,
	IB_CM_REJ_PORT_CM_REDIRECT		= 24,
	IB_CM_REJ_PORT_REDIRECT			= 25,
	IB_CM_REJ_INVALID_MTU			= 26,
	IB_CM_REJ_INSUFFICIENT_RESP_RESOURCES	= 27,
	IB_CM_REJ_CONSUMER_DEFINED		= 28,
	IB_CM_REJ_INVALID_RNR_RETRY		= 29,
	IB_CM_REJ_DUPLICATE_LOCAL_COMM_ID	= 30,
	IB_CM_REJ_INVALID_CLASS_VERSION		= 31,
	IB_CM_REJ_INVALID_FLOW_LABEL		= 32,
	IB_CM_REJ_INVALID_ALT_FLOW_LABEL	= 33,
	IB_CM_REJ_VENDOR_OPTION_NOT_SUPPORTED	= 35,
};

string

drivers/infiniband/core/cm.c

static const char * const ibcm_rej_reason_strs[] = {
	[IB_CM_REJ_NO_QP]			= "no QP",
	[IB_CM_REJ_NO_EEC]			= "no EEC",
	[IB_CM_REJ_NO_RESOURCES]		= "no resources",
	[IB_CM_REJ_TIMEOUT]			= "timeout",
	[IB_CM_REJ_UNSUPPORTED]			= "unsupported",
	[IB_CM_REJ_INVALID_COMM_ID]		= "invalid comm ID",
	[IB_CM_REJ_INVALID_COMM_INSTANCE]	= "invalid comm instance",
	[IB_CM_REJ_INVALID_SERVICE_ID]		= "invalid service ID",
	[IB_CM_REJ_INVALID_TRANSPORT_TYPE]	= "invalid transport type",
	[IB_CM_REJ_STALE_CONN]			= "stale conn",
	[IB_CM_REJ_RDC_NOT_EXIST]		= "RDC not exist",
	[IB_CM_REJ_INVALID_GID]			= "invalid GID",
	[IB_CM_REJ_INVALID_LID]			= "invalid LID",
	[IB_CM_REJ_INVALID_SL]			= "invalid SL",
	[IB_CM_REJ_INVALID_TRAFFIC_CLASS]	= "invalid traffic class",
	[IB_CM_REJ_INVALID_HOP_LIMIT]		= "invalid hop limit",
	[IB_CM_REJ_INVALID_PACKET_RATE]		= "invalid packet rate",
	[IB_CM_REJ_INVALID_ALT_GID]		= "invalid alt GID",
	[IB_CM_REJ_INVALID_ALT_LID]		= "invalid alt LID",
	[IB_CM_REJ_INVALID_ALT_SL]		= "invalid alt SL",
	[IB_CM_REJ_INVALID_ALT_TRAFFIC_CLASS]	= "invalid alt traffic class",
	[IB_CM_REJ_INVALID_ALT_HOP_LIMIT]	= "invalid alt hop limit",
	[IB_CM_REJ_INVALID_ALT_PACKET_RATE]	= "invalid alt packet rate",
	[IB_CM_REJ_PORT_CM_REDIRECT]		= "port CM redirect",
	[IB_CM_REJ_PORT_REDIRECT]		= "port redirect",
	[IB_CM_REJ_INVALID_MTU]			= "invalid MTU",
	[IB_CM_REJ_INSUFFICIENT_RESP_RESOURCES]	= "insufficient resp resources",
	[IB_CM_REJ_CONSUMER_DEFINED]		= "consumer defined",
	[IB_CM_REJ_INVALID_RNR_RETRY]		= "invalid RNR retry",
	[IB_CM_REJ_DUPLICATE_LOCAL_COMM_ID]	= "duplicate local comm ID",
	[IB_CM_REJ_INVALID_CLASS_VERSION]	= "invalid class version",
	[IB_CM_REJ_INVALID_FLOW_LABEL]		= "invalid flow label",
	[IB_CM_REJ_INVALID_ALT_FLOW_LABEL]	= "invalid alt flow label",
	[IB_CM_REJ_VENDOR_OPTION_NOT_SUPPORTED] = "vendor option is not supported",
};

获取string方式

可以看到是OFED通用的转string方法，用边长数组+宏定义结构化初始化。然后用

const char *__attribute_const__ ibcm_reject_msg(int reason)
{
	size_t index = reason;

	if (index < ARRAY_SIZE(ibcm_rej_reason_strs) &&
	    ibcm_rej_reason_strs[index])
		return ibcm_rej_reason_strs[index];
	else
		return "unrecognized reason";
}
EXPORT_SYMBOL(ibcm_reject_msg);

//#define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))


const char *__attribute_const__ rdma_reject_msg(struct rdma_cm_id *id,
						int reason)
{
	if (rdma_ib_or_roce(id->device, id->port_num))
		return ibcm_reject_msg(reason);

	if (rdma_protocol_iwarp(id->device, id->port_num))
		return iwcm_reject_msg(reason);

	WARN_ON_ONCE(1);
	return "unrecognized transport";
}
EXPORT_SYMBOL(rdma_reject_msg);

static int cma_ib_handler(struct ib_cm_id *cm_id, ...)
{
	switch (ib_event->event) {
		case IB_CM_REJ_RECEIVED:
			pr_debug_ratelimited("RDMA CM: REJECTED: %s\n", rdma_reject_msg(&id_priv->id, ib_event->param.rej_rcvd.reason));
}