libwd/0139-drv-qm-modify-the-lock-for-send-and-receive-BD.patch

From 2004801f44c0b6259b051e5a55bde5c54306fd63 Mon Sep 17 00:00:00 2001
From: Weili Qian <qianweili@huawei.com>
Date: Mon, 18 Jul 2022 10:17:06 +0800
Subject: [PATCH 154/183] drv/qm: modify the lock for send and receive BD

If the same lock is used for BD receiving and BD sending,
the BD receiving and BD sending threads compete for lock in
asynchronous scenarios, affecting tasks performance.

Signed-off-by: Weili Qian <qianweili@huawei.com>
---
 drv/hisi_qm_udrv.c     | 38 +++++++++++++++++++++++++-------------
 include/hisi_qm_udrv.h |  3 ++-
 2 files changed, 27 insertions(+), 14 deletions(-)

diff --git a/drv/hisi_qm_udrv.c b/drv/hisi_qm_udrv.c
index f1468a4..da756c4 100644
--- a/drv/hisi_qm_udrv.c
+++ b/drv/hisi_qm_udrv.c
@@ -322,14 +322,22 @@ static int hisi_qm_setup_info(struct hisi_qp *qp, struct hisi_qm_priv *config)
 		q_info->region_size[UACCE_QFRT_DUS] - sizeof(uint32_t);
 	q_info->ds_rx_base = q_info->ds_tx_base - sizeof(uint32_t);
 
-	ret = pthread_spin_init(&q_info->lock, PTHREAD_PROCESS_SHARED);
+	ret = pthread_spin_init(&q_info->rv_lock, PTHREAD_PROCESS_SHARED);
 	if (ret) {
-		WD_DEV_ERR(qp->h_ctx, "failed to init qinfo lock!\n");
+		WD_DEV_ERR(qp->h_ctx, "failed to init qinfo rv_lock!\n");
 		goto err_out;
 	}
 
+	ret = pthread_spin_init(&q_info->sd_lock, PTHREAD_PROCESS_SHARED);
+	if (ret) {
+		WD_DEV_ERR(qp->h_ctx, "failed to init qinfo sd_lock!\n");
+		goto err_destory_lock;
+	}
+
 	return 0;
 
+err_destory_lock:
+	pthread_spin_destroy(&q_info->rv_lock);
 err_out:
 	hisi_qm_unset_region(qp->h_ctx, q_info);
 	return ret;
@@ -339,14 +347,16 @@ static void hisi_qm_clear_info(struct hisi_qp *qp)
 {
 	struct hisi_qm_queue_info *q_info = &qp->q_info;
 
-	pthread_spin_destroy(&q_info->lock);
+	pthread_spin_destroy(&q_info->sd_lock);
+	pthread_spin_destroy(&q_info->rv_lock);
 	hisi_qm_unset_region(qp->h_ctx, q_info);
 }
 
 static int get_free_num(struct hisi_qm_queue_info *q_info)
 {
 	/* The device should reserve one buffer. */
-	return (QM_Q_DEPTH - 1) - q_info->used_num;
+	return (QM_Q_DEPTH - 1) -
+		__atomic_load_n(&q_info->used_num, __ATOMIC_RELAXED);
 }
 
 int hisi_qm_get_free_sqe_num(handle_t h_qp)
@@ -441,10 +451,10 @@ int hisi_qm_send(handle_t h_qp, const void *req, __u16 expect, __u16 *count)
 		return -WD_HW_EACCESS;
 	}
 
-	pthread_spin_lock(&q_info->lock);
+	pthread_spin_lock(&q_info->sd_lock);
 	free_num = get_free_num(q_info);
 	if (!free_num) {
-		pthread_spin_unlock(&q_info->lock);
+		pthread_spin_unlock(&q_info->sd_lock);
 		return -WD_EBUSY;
 	}
 
@@ -455,10 +465,12 @@ int hisi_qm_send(handle_t h_qp, const void *req, __u16 expect, __u16 *count)
 	tail = (tail + send_num) % QM_Q_DEPTH;
 	q_info->db(q_info, QM_DBELL_CMD_SQ, tail, 0);
 	q_info->sq_tail_index = tail;
-	q_info->used_num += send_num;
+
+	/* Make sure used_num is changed before the next thread gets free sqe. */
+	__atomic_add_fetch(&q_info->used_num, send_num, __ATOMIC_RELAXED);
 	*count = send_num;
 
-	pthread_spin_unlock(&q_info->lock);
+	pthread_spin_unlock(&q_info->sd_lock);
 
 	return 0;
 }
@@ -469,21 +481,21 @@ static int hisi_qm_recv_single(struct hisi_qm_queue_info *q_info, void *resp)
 	struct cqe *cqe;
 	__u16 i, j;
 
-	pthread_spin_lock(&q_info->lock);
+	pthread_spin_lock(&q_info->rv_lock);
 	i = q_info->cq_head_index;
 	cqe = q_info->cq_base + i * sizeof(struct cqe);
 
 	if (q_info->cqc_phase == CQE_PHASE(cqe)) {
 		j = CQE_SQ_HEAD_INDEX(cqe);
 		if (j >= QM_Q_DEPTH) {
-			pthread_spin_unlock(&q_info->lock);
+			pthread_spin_unlock(&q_info->rv_lock);
 			WD_DEV_ERR(qp->h_ctx, "CQE_SQ_HEAD_INDEX(%u) error!\n", j);
 			return -WD_EIO;
 		}
 		memcpy(resp, (void *)((uintptr_t)q_info->sq_base +
 			j * q_info->sqe_size), q_info->sqe_size);
 	} else {
-		pthread_spin_unlock(&q_info->lock);
+		pthread_spin_unlock(&q_info->rv_lock);
 		return -WD_EAGAIN;
 	}
 
@@ -500,8 +512,8 @@ static int hisi_qm_recv_single(struct hisi_qm_queue_info *q_info, void *resp)
 	q_info->cq_head_index = i;
 	q_info->sq_head_index = i;
 
-	q_info->used_num--;
-	pthread_spin_unlock(&q_info->lock);
+	__atomic_sub_fetch(&q_info->used_num, 1, __ATOMIC_RELAXED);
+	pthread_spin_unlock(&q_info->rv_lock);
 
 	return 0;
 }
diff --git a/include/hisi_qm_udrv.h b/include/hisi_qm_udrv.h
index 88758ac..92333ed 100644
--- a/include/hisi_qm_udrv.h
+++ b/include/hisi_qm_udrv.h
@@ -75,7 +75,8 @@ struct hisi_qm_queue_info {
 	__u16 hw_type;
 	__u32 idx;
 	bool cqc_phase;
-	pthread_spinlock_t lock;
+	pthread_spinlock_t sd_lock;
+	pthread_spinlock_t rv_lock;
 	unsigned long region_size[UACCE_QFRT_MAX];
 	bool epoll_en;
 };
-- 
2.27.0