This is a note to let you know that I've just added the patch titled
RDMA/hns: Bugfix for checking whether the srq is full when post wr
to the 5.11-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
rdma-hns-bugfix-for-checking-whether-the-srq-is-full.patch
and it can be found in the queue-5.11 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit b1bac9e97160949f03e616692bb04d1bfc2ca330
Author: Wenpeng Liang <liangwenpeng@xxxxxxxxxx>
Date: Sat Jan 30 16:58:00 2021 +0800
RDMA/hns: Bugfix for checking whether the srq is full when post wr
[ Upstream commit 1620f09b96ec14c1ff1ff64ee0aeabc027c653d5 ]
If a user posts WR by wr_list, the head pointer of idx_queue won't be
updated until all wqes are filled, so the judgment of whether head equals
to tail will get a wrong result. Fix above issue and move the head and
tail pointer from the srq structure into the idx_queue structure. After
idx_queue is filled with wqe idx, the head pointer of it will increase.
Fixes: c7bcb13442e1 ("RDMA/hns: Add SRQ support for hip08 kernel mode")
Link: https://lore.kernel.org/r/1611997090-48820-3-git-send-email-liweihang@xxxxxxxxxx
Signed-off-by: Wenpeng Liang <liangwenpeng@xxxxxxxxxx>
Signed-off-by: Weihang Li <liweihang@xxxxxxxxxx>
Signed-off-by: Jason Gunthorpe <jgg@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/infiniband/hw/hns/hns_roce_device.h b/drivers/infiniband/hw/hns/hns_roce_device.h
index dd3e3886ab96d..2e42e25957938 100644
--- a/drivers/infiniband/hw/hns/hns_roce_device.h
+++ b/drivers/infiniband/hw/hns/hns_roce_device.h
@@ -492,6 +492,8 @@ struct hns_roce_idx_que {
struct hns_roce_mtr mtr;
int entry_shift;
unsigned long *bitmap;
+ u32 head;
+ u32 tail;
};
struct hns_roce_srq {
@@ -511,8 +513,6 @@ struct hns_roce_srq {
u64 *wrid;
struct hns_roce_idx_que idx_que;
spinlock_t lock;
- u16 head;
- u16 tail;
struct mutex mutex;
void (*event)(struct hns_roce_srq *srq, enum hns_roce_event event);
};
diff --git a/drivers/infiniband/hw/hns/hns_roce_hw_v2.c b/drivers/infiniband/hw/hns/hns_roce_hw_v2.c
index 4d1e4bddf8327..c05e418b6e538 100644
--- a/drivers/infiniband/hw/hns/hns_roce_hw_v2.c
+++ b/drivers/infiniband/hw/hns/hns_roce_hw_v2.c
@@ -849,11 +849,20 @@ static void hns_roce_free_srq_wqe(struct hns_roce_srq *srq, int wqe_index)
spin_lock(&srq->lock);
bitmap_clear(srq->idx_que.bitmap, wqe_index, 1);
- srq->tail++;
+ srq->idx_que.tail++;
spin_unlock(&srq->lock);
}
+int hns_roce_srqwq_overflow(struct hns_roce_srq *srq, int nreq)
+{
+ struct hns_roce_idx_que *idx_que = &srq->idx_que;
+ unsigned int cur;
+
+ cur = idx_que->head - idx_que->tail;
+ return cur + nreq >= srq->wqe_cnt - 1;
+}
+
static int find_empty_entry(struct hns_roce_idx_que *idx_que,
unsigned long size)
{
@@ -889,7 +898,7 @@ static int hns_roce_v2_post_srq_recv(struct ib_srq *ibsrq,
spin_lock_irqsave(&srq->lock, flags);
- 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) {
@@ -902,7 +911,7 @@ static int hns_roce_v2_post_srq_recv(struct ib_srq *ibsrq,
break;
}
- if (unlikely(srq->head == srq->tail)) {
+ if (unlikely(hns_roce_srqwq_overflow(srq, nreq))) {
ret = -ENOMEM;
*bad_wr = wr;
break;
@@ -938,7 +947,7 @@ static int hns_roce_v2_post_srq_recv(struct ib_srq *ibsrq,
}
if (likely(nreq)) {
- srq->head += nreq;
+ srq->idx_que.head += nreq;
/*
* Make sure that descriptors are written before
@@ -950,7 +959,7 @@ static int hns_roce_v2_post_srq_recv(struct ib_srq *ibsrq,
cpu_to_le32(HNS_ROCE_V2_SRQ_DB << V2_DB_BYTE_4_CMD_S |
(srq->srqn & V2_DB_BYTE_4_TAG_M));
srq_db.parameter =
- cpu_to_le32(srq->head & V2_DB_PARAMETER_IDX_M);
+ cpu_to_le32(srq->idx_que.head & V2_DB_PARAMETER_IDX_M);
hns_roce_write64(hr_dev, (__le32 *)&srq_db, srq->db_reg_l);
}
diff --git a/drivers/infiniband/hw/hns/hns_roce_srq.c b/drivers/infiniband/hw/hns/hns_roce_srq.c
index 8e20085b8920a..9f60a0a745e11 100644
--- a/drivers/infiniband/hw/hns/hns_roce_srq.c
+++ b/drivers/infiniband/hw/hns/hns_roce_srq.c
@@ -247,6 +247,9 @@ static int alloc_srq_idx(struct hns_roce_dev *hr_dev, struct hns_roce_srq *srq,
}
}
+ idx_que->head = 0;
+ idx_que->tail = 0;
+
return 0;
err_idx_mtr:
hns_roce_mtr_destroy(hr_dev, &idx_que->mtr);
@@ -265,8 +268,6 @@ static void free_srq_idx(struct hns_roce_dev *hr_dev, struct hns_roce_srq *srq)
static int alloc_srq_wrid(struct hns_roce_dev *hr_dev, struct hns_roce_srq *srq)
{
- srq->head = 0;
- srq->tail = srq->wqe_cnt - 1;
srq->wrid = kvmalloc_array(srq->wqe_cnt, sizeof(u64), GFP_KERNEL);
if (!srq->wrid)
return -ENOMEM;
