This is a note to let you know that I've just added the patch titled RDMA/hns: Use mutex instead of spinlock for ida allocation to the 5.10-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-use-mutex-instead-of-spinlock-for-ida-alloc.patch and it can be found in the queue-5.10 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit e4a7a24051aa8509723f98d1f2c016d36f376963 Author: Yangyang Li <liyangyang20@xxxxxxxxxx> Date: Tue Jan 19 17:28:33 2021 +0800 RDMA/hns: Use mutex instead of spinlock for ida allocation [ Upstream commit 9293d3fcb70583f2c786f04ca788af026b7c4c5c ] GFP_KERNEL may cause ida_alloc_range() to sleep, but the spinlock covering this function is not allowed to sleep, so the spinlock needs to be changed to mutex. As there is a certain chance of memory allocation failure, GFP_ATOMIC is not suitable for QP allocation scenarios. Fixes: 71586dd20010 ("RDMA/hns: Create QP with selected QPN for bank load balance") Link: https://lore.kernel.org/r/1611048513-28663-1-git-send-email-liweihang@xxxxxxxxxx Signed-off-by: Yangyang Li <liyangyang20@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 db78bc2d44c21..385f26ef57e12 100644 --- a/drivers/infiniband/hw/hns/hns_roce_device.h +++ b/drivers/infiniband/hw/hns/hns_roce_device.h @@ -537,7 +537,7 @@ struct hns_roce_qp_table { struct hns_roce_hem_table sccc_table; struct mutex scc_mutex; struct hns_roce_bank bank[HNS_ROCE_QP_BANK_NUM]; - spinlock_t bank_lock; + struct mutex bank_mutex; }; struct hns_roce_cq_table { diff --git a/drivers/infiniband/hw/hns/hns_roce_qp.c b/drivers/infiniband/hw/hns/hns_roce_qp.c index 3ed43a5c7596b..5af36bb326b98 100644 --- a/drivers/infiniband/hw/hns/hns_roce_qp.c +++ b/drivers/infiniband/hw/hns/hns_roce_qp.c @@ -210,7 +210,7 @@ static int alloc_qpn(struct hns_roce_dev *hr_dev, struct hns_roce_qp *hr_qp) hr_qp->doorbell_qpn = 1; } else { - spin_lock(&qp_table->bank_lock); + mutex_lock(&qp_table->bank_mutex); bankid = get_least_load_bankid_for_qp(qp_table->bank); ret = alloc_qpn_with_bankid(&qp_table->bank[bankid], bankid, @@ -218,12 +218,12 @@ static int alloc_qpn(struct hns_roce_dev *hr_dev, struct hns_roce_qp *hr_qp) if (ret) { ibdev_err(&hr_dev->ib_dev, "failed to alloc QPN, ret = %d\n", ret); - spin_unlock(&qp_table->bank_lock); + mutex_unlock(&qp_table->bank_mutex); return ret; } qp_table->bank[bankid].inuse++; - spin_unlock(&qp_table->bank_lock); + mutex_unlock(&qp_table->bank_mutex); hr_qp->doorbell_qpn = (u32)num; } @@ -409,9 +409,9 @@ static void free_qpn(struct hns_roce_dev *hr_dev, struct hns_roce_qp *hr_qp) ida_free(&hr_dev->qp_table.bank[bankid].ida, hr_qp->qpn >> 3); - spin_lock(&hr_dev->qp_table.bank_lock); + mutex_lock(&hr_dev->qp_table.bank_mutex); hr_dev->qp_table.bank[bankid].inuse--; - spin_unlock(&hr_dev->qp_table.bank_lock); + mutex_unlock(&hr_dev->qp_table.bank_mutex); } static int set_rq_size(struct hns_roce_dev *hr_dev, struct ib_qp_cap *cap, @@ -1358,6 +1358,7 @@ int hns_roce_init_qp_table(struct hns_roce_dev *hr_dev) unsigned int i; mutex_init(&qp_table->scc_mutex); + mutex_init(&qp_table->bank_mutex); xa_init(&hr_dev->qp_table_xa); reserved_from_bot = hr_dev->caps.reserved_qps;