RDMA/hns: Get message length of ack_req from FW

ACK_REQ_FREQ indicates the number of packets (after MTU fragmentation)
HW sends before setting an ACK request. When MTU is greater than or
equal to 1024, the current ACK_REQ_FREQ value causes HW to request an
ACK for every MTU fragment. The processing of a large number of ACKs
severely impacts HW performance when sending large size payloads.

Get message length of ack_req from FW so that we can adjust this
parameter according to different situations. There are several
constraints for ACK_REQ_FREQ:

1. mtu * (2 ^ ACK_REQ_FREQ) should not be too large, otherwise it may
   cause some unexpected retries when sending large payload.

2. ACK_REQ_FREQ should be larger than or equal to LP_PKTN_INI.

3. ACK_REQ_FREQ must be equal to LP_PKTN_INI when using LDCP
   or HC3 congestion control algorithm.

Fixes: 56518a603fd2 ("RDMA/hns: Modify the value of long message loopback slice")
Signed-off-by: Junxian Huang <huangjunxian6@hisilicon.com>
Link: https://patch.msgid.link/20250703113905.3597124-4-huangjunxian6@hisilicon.com
Signed-off-by: Leon Romanovsky <leon@kernel.org>

diff --git a/drivers/infiniband/hw/hns/hns_roce_device.h b/drivers/infiniband/hw/hns/hns_roce_device.h
index 40dcf77e2d9216932253804733ee1b4e7a92fc93..25f77b1fa7738d10113cdc4e85adc7e3dc1f7e6c 100644 (file)
--- a/drivers/infiniband/hw/hns/hns_roce_device.h
+++ b/drivers/infiniband/hw/hns/hns_roce_device.h
@@ -846,6 +846,7 @@ struct hns_roce_caps {
        u16             default_ceq_arm_st;
        u8              cong_cap;
        enum hns_roce_cong_type default_cong_type;
+       u32             max_ack_req_msg_len;
 };
 
 enum hns_roce_device_state {

diff --git a/drivers/infiniband/hw/hns/hns_roce_hw_v2.c b/drivers/infiniband/hw/hns/hns_roce_hw_v2.c
index 4f2dbc3ffb31f4b9981ae4b5c0e4cb8292e0fede..2e9ef2fb8019a2aa275bedc922d8127c66974176 100644 (file)
--- a/drivers/infiniband/hw/hns/hns_roce_hw_v2.c
+++ b/drivers/infiniband/hw/hns/hns_roce_hw_v2.c
@@ -2196,31 +2196,36 @@ static void apply_func_caps(struct hns_roce_dev *hr_dev)
 
 static int hns_roce_query_caps(struct hns_roce_dev *hr_dev)
 {
-       struct hns_roce_cmq_desc desc[HNS_ROCE_QUERY_PF_CAPS_CMD_NUM];
+       struct hns_roce_cmq_desc desc[HNS_ROCE_QUERY_PF_CAPS_CMD_NUM] = {};
        struct hns_roce_caps *caps = &hr_dev->caps;
        struct hns_roce_query_pf_caps_a *resp_a;
        struct hns_roce_query_pf_caps_b *resp_b;
        struct hns_roce_query_pf_caps_c *resp_c;
        struct hns_roce_query_pf_caps_d *resp_d;
        struct hns_roce_query_pf_caps_e *resp_e;
+       struct hns_roce_query_pf_caps_f *resp_f;
        enum hns_roce_opcode_type cmd;
        int ctx_hop_num;
        int pbl_hop_num;
+       int cmd_num;
        int ret;
        int i;
 
        cmd = hr_dev->is_vf ? HNS_ROCE_OPC_QUERY_VF_CAPS_NUM :
              HNS_ROCE_OPC_QUERY_PF_CAPS_NUM;
+       cmd_num = hr_dev->pci_dev->revision == PCI_REVISION_ID_HIP08 ?
+                 HNS_ROCE_QUERY_PF_CAPS_CMD_NUM_HIP08 :
+                 HNS_ROCE_QUERY_PF_CAPS_CMD_NUM;
 
-       for (i = 0; i < HNS_ROCE_QUERY_PF_CAPS_CMD_NUM; i++) {
+       for (i = 0; i < cmd_num - 1; i++) {
                hns_roce_cmq_setup_basic_desc(&desc[i], cmd, true);
-               if (i < (HNS_ROCE_QUERY_PF_CAPS_CMD_NUM - 1))
-                       desc[i].flag |= cpu_to_le16(HNS_ROCE_CMD_FLAG_NEXT);
-               else
-                       desc[i].flag &= ~cpu_to_le16(HNS_ROCE_CMD_FLAG_NEXT);
+               desc[i].flag |= cpu_to_le16(HNS_ROCE_CMD_FLAG_NEXT);
        }
 
-       ret = hns_roce_cmq_send(hr_dev, desc, HNS_ROCE_QUERY_PF_CAPS_CMD_NUM);
+       hns_roce_cmq_setup_basic_desc(&desc[cmd_num - 1], cmd, true);
+       desc[cmd_num - 1].flag &= ~cpu_to_le16(HNS_ROCE_CMD_FLAG_NEXT);
+
+       ret = hns_roce_cmq_send(hr_dev, desc, cmd_num);
        if (ret)
                return ret;
 
@@ -2229,6 +2234,7 @@ static int hns_roce_query_caps(struct hns_roce_dev *hr_dev)
        resp_c = (struct hns_roce_query_pf_caps_c *)desc[2].data;
        resp_d = (struct hns_roce_query_pf_caps_d *)desc[3].data;
        resp_e = (struct hns_roce_query_pf_caps_e *)desc[4].data;
+       resp_f = (struct hns_roce_query_pf_caps_f *)desc[5].data;
 
        caps->local_ca_ack_delay = resp_a->local_ca_ack_delay;
        caps->max_sq_sg = le16_to_cpu(resp_a->max_sq_sg);
@@ -2293,6 +2299,8 @@ static int hns_roce_query_caps(struct hns_roce_dev *hr_dev)
        caps->reserved_srqs = hr_reg_read(resp_e, PF_CAPS_E_RSV_SRQS);
        caps->reserved_lkey = hr_reg_read(resp_e, PF_CAPS_E_RSV_LKEYS);
 
+       caps->max_ack_req_msg_len = le32_to_cpu(resp_f->max_ack_req_msg_len);
+
        caps->qpc_hop_num = ctx_hop_num;
        caps->sccc_hop_num = ctx_hop_num;
        caps->srqc_hop_num = ctx_hop_num;
@@ -4535,7 +4543,9 @@ static int modify_qp_init_to_rtr(struct ib_qp *ibqp,
        dma_addr_t trrl_ba;
        dma_addr_t irrl_ba;
        enum ib_mtu ib_mtu;
+       u8 ack_req_freq;
        const u8 *smac;
+       int lp_msg_len;
        u8 lp_pktn_ini;
        u64 *mtts;
        u8 *dmac;
@@ -4618,7 +4628,8 @@ static int modify_qp_init_to_rtr(struct ib_qp *ibqp,
                return -EINVAL;
 #define MIN_LP_MSG_LEN 1024
        /* mtu * (2 ^ lp_pktn_ini) should be in the range of 1024 to mtu */
-       lp_pktn_ini = ilog2(max(mtu, MIN_LP_MSG_LEN) / mtu);
+       lp_msg_len = max(mtu, MIN_LP_MSG_LEN);
+       lp_pktn_ini = ilog2(lp_msg_len / mtu);
 
        if (attr_mask & IB_QP_PATH_MTU) {
                hr_reg_write(context, QPC_MTU, ib_mtu);
@@ -4628,8 +4639,22 @@ static int modify_qp_init_to_rtr(struct ib_qp *ibqp,
        hr_reg_write(context, QPC_LP_PKTN_INI, lp_pktn_ini);
        hr_reg_clear(qpc_mask, QPC_LP_PKTN_INI);
 
-       /* ACK_REQ_FREQ should be larger than or equal to LP_PKTN_INI */
-       hr_reg_write(context, QPC_ACK_REQ_FREQ, lp_pktn_ini);
+       /*
+        * There are several constraints for ACK_REQ_FREQ:
+        * 1. mtu * (2 ^ ACK_REQ_FREQ) should not be too large, otherwise
+        *    it may cause some unexpected retries when sending large
+        *    payload.
+        * 2. ACK_REQ_FREQ should be larger than or equal to LP_PKTN_INI.
+        * 3. ACK_REQ_FREQ must be equal to LP_PKTN_INI when using LDCP
+        *    or HC3 congestion control algorithm.
+        */
+       if (hr_qp->cong_type == CONG_TYPE_LDCP ||
+           hr_qp->cong_type == CONG_TYPE_HC3 ||
+           hr_dev->caps.max_ack_req_msg_len < lp_msg_len)
+               ack_req_freq = lp_pktn_ini;
+       else
+               ack_req_freq = ilog2(hr_dev->caps.max_ack_req_msg_len / mtu);
+       hr_reg_write(context, QPC_ACK_REQ_FREQ, ack_req_freq);
        hr_reg_clear(qpc_mask, QPC_ACK_REQ_FREQ);
 
        hr_reg_clear(qpc_mask, QPC_RX_REQ_PSN_ERR);

diff --git a/drivers/infiniband/hw/hns/hns_roce_hw_v2.h b/drivers/infiniband/hw/hns/hns_roce_hw_v2.h
index be8ef8ddd4224048239d3557607b9098fefc8634..e64a04d6f85b7d48a50481f3befa8d45cda3af82 100644 (file)
--- a/drivers/infiniband/hw/hns/hns_roce_hw_v2.h
+++ b/drivers/infiniband/hw/hns/hns_roce_hw_v2.h
@@ -1160,7 +1160,8 @@ struct hns_roce_cfg_gmv_tb_b {
 #define GMV_TB_B_SMAC_H GMV_TB_B_FIELD_LOC(47, 32)
 #define GMV_TB_B_SGID_IDX GMV_TB_B_FIELD_LOC(71, 64)
 
-#define HNS_ROCE_QUERY_PF_CAPS_CMD_NUM 5
+#define HNS_ROCE_QUERY_PF_CAPS_CMD_NUM_HIP08 5
+#define HNS_ROCE_QUERY_PF_CAPS_CMD_NUM 6
 struct hns_roce_query_pf_caps_a {
        u8 number_ports;
        u8 local_ca_ack_delay;
@@ -1272,6 +1273,11 @@ struct hns_roce_query_pf_caps_e {
        __le16 aeq_period;
 };
 
+struct hns_roce_query_pf_caps_f {
+       __le32 max_ack_req_msg_len;
+       __le32 rsv[5];
+};
+
 #define PF_CAPS_E_FIELD_LOC(h, l) \
        FIELD_LOC(struct hns_roce_query_pf_caps_e, h, l)