rdma-core/0002-libhns-Fix-the-ownership-of-the-head-tail-pointer-of.patch

From 08ec3c43bf9710fdf3ca664f7cd63436e67339d7 Mon Sep 17 00:00:00 2001
From: Wenpeng Liang <liangwenpeng@huawei.com>
Date: Tue, 11 May 2021 19:06:34 +0800
Subject: [PATCH 2/8] libhns: Fix the ownership of the head/tail pointer of SRQ
 WQE

The CQE of SRQ is not generated in the order of wqe, so the wqe_idx
corresponding to the idle WQE should be placed in a FIFO, then the hardware
will be instructed to obtain the corresponding WQE. Therefore, the WQ
of SRQ has no concept of head pointer and tail pointer, but the queue of
wqe_idx does.

Signed-off-by: Wenpeng Liang <liangwenpeng@huawei.com>
Signed-off-by: Weihang Li <liweihang@huawei.com>
---
 providers/hns/hns_roce_u.h       |  4 ++--
 providers/hns/hns_roce_u_hw_v2.c | 12 ++++++------
 providers/hns/hns_roce_u_verbs.c |  6 +++---
 3 files changed, 11 insertions(+), 11 deletions(-)

diff --git a/providers/hns/hns_roce_u.h b/providers/hns/hns_roce_u.h
index 8f805dd1..b3f48113 100644
--- a/providers/hns/hns_roce_u.h
+++ b/providers/hns/hns_roce_u.h
@@ -205,6 +205,8 @@ struct hns_roce_idx_que {
 	int				entry_shift;
 	unsigned long			*bitmap;
 	int				bitmap_cnt;
+	unsigned int			head;
+	unsigned int			tail;
 };

 struct hns_roce_srq {
@@ -217,8 +219,6 @@ struct hns_roce_srq {
 	unsigned int			max_gs;
 	unsigned int			rsv_sge;
 	unsigned int			wqe_shift;
-	int				head;
-	int				tail;
 	unsigned int			*db;
 	unsigned short			counter;
 	struct hns_roce_idx_que		idx_que;
diff --git a/providers/hns/hns_roce_u_hw_v2.c b/providers/hns/hns_roce_u_hw_v2.c
index 4988943a..f947dbd7 100644
--- a/providers/hns/hns_roce_u_hw_v2.c
+++ b/providers/hns/hns_roce_u_hw_v2.c
@@ -262,7 +262,7 @@ static void hns_roce_free_srq_wqe(struct hns_roce_srq *srq, uint16_t ind)
 	bitmap_num = ind / BIT_CNT_PER_LONG;
 	bit_num = ind % BIT_CNT_PER_LONG;
 	srq->idx_que.bitmap[bitmap_num] |= (1ULL << bit_num);
-	srq->tail++;
+	srq->idx_que.tail++;

 	pthread_spin_unlock(&srq->lock);
 }
@@ -1564,7 +1564,7 @@ static int hns_roce_u_v2_post_srq_recv(struct ibv_srq *ib_srq,
 	pthread_spin_lock(&srq->lock);

 	/* current idx of srqwq */
-	ind = srq->head & (srq->wqe_cnt - 1);
+	ind = srq->idx_que.head & (srq->wqe_cnt - 1);

 	max_sge = srq->max_gs - srq->rsv_sge;
 	for (nreq = 0; wr; ++nreq, wr = wr->next) {
@@ -1574,7 +1574,7 @@ static int hns_roce_u_v2_post_srq_recv(struct ibv_srq *ib_srq,
 			break;
 		}

-		if (srq->head == srq->tail) {
+		if (srq->idx_que.head == srq->idx_que.tail) {
 			ret = -ENOMEM;
 			*bad_wr = wr;
 			break;
@@ -1607,7 +1607,7 @@ static int hns_roce_u_v2_post_srq_recv(struct ibv_srq *ib_srq,
 	}

 	if (nreq) {
-		srq->head += nreq;
+		srq->idx_que.head += nreq;

 		/*
 		 * Make sure that descriptors are written before
@@ -1617,8 +1617,8 @@ static int hns_roce_u_v2_post_srq_recv(struct ibv_srq *ib_srq,

 		srq_db.byte_4 = htole32(HNS_ROCE_V2_SRQ_DB << DB_BYTE_4_CMD_S |
 					srq->srqn);
-		srq_db.parameter =
-			htole32(srq->head & DB_PARAM_SRQ_PRODUCER_COUNTER_M);
+		srq_db.parameter = htole32(srq->idx_que.head &
+					   DB_PARAM_SRQ_PRODUCER_COUNTER_M);

 		hns_roce_write64((uint32_t *)&srq_db, ctx,
 				 ROCEE_VF_DB_CFG0_OFFSET);
diff --git a/providers/hns/hns_roce_u_verbs.c b/providers/hns/hns_roce_u_verbs.c
index 30ab072a..9b4934b9 100644
--- a/providers/hns/hns_roce_u_verbs.c
+++ b/providers/hns/hns_roce_u_verbs.c
@@ -491,6 +491,9 @@ static int hns_roce_create_idx_que(struct hns_roce_srq *srq)
 	for (i = 0; i < idx_que->bitmap_cnt; ++i)
 		idx_que->bitmap[i] = ~(0UL);

+	idx_que->head = 0;
+	idx_que->tail = srq->wqe_cnt - 1;
+
 	return 0;
 }

@@ -512,9 +515,6 @@ static int hns_roce_alloc_srq_buf(struct hns_roce_srq *srq)
 		return ENOMEM;
 	}

-	srq->head = 0;
-	srq->tail = srq->wqe_cnt - 1;
-
 	return 0;
 }

--
2.33.0