On 2024/11/8 15:11, Zhu Yanjun wrote:
> 在 2024/11/7 7:11, Junxian Huang 写道:
>> From: Feng Fang <fangfeng4@xxxxxxxxxx>
>>
>> DIP algorithm requires a one-to-one mapping between dgid and dip_idx.
>> Currently a queue 'spare_idx' is used to store QPN of QPs that use
>> DIP algorithm. For a new dgid, use a QPN from spare_idx as dip_idx.
>> This method lacks a mechanism for deduplicating QPN, which may result
>> in different dgids sharing the same dip_idx and break the one-to-one
>> mapping requirement.
>>
>> This patch replaces spare_idx with xarray and introduces a refcnt of
>> a dip_idx to indicate the number of QPs that using this dip_idx.
>>
>> The state machine for dip_idx management is implemented as:
>>
>> * The entry at an index in xarray is empty -- This indicates that the
>> corresponding dip_idx hasn't been created.
>>
>> * The entry at an index in xarray is not empty but with 0 refcnt --
>> This indicates that the corresponding dip_idx has been created but
>> not used as dip_idx yet.
>>
>> * The entry at an index in xarray is not empty and with non-0 refcnt --
>> This indicates that the corresponding dip_idx is being used by refcnt
>> number of DIP QPs.
>>
>> Fixes: eb653eda1e91 ("RDMA/hns: Bugfix for incorrect association between dip_idx and dgid")
>> Fixes: f91696f2f053 ("RDMA/hns: Support congestion control type selection according to the FW")
>> Signed-off-by: Feng Fang <fangfeng4@xxxxxxxxxx>
>> Signed-off-by: Junxian Huang <huangjunxian6@xxxxxxxxxxxxx>
>> ---
>> v1 -> v2:
>> * Use xarray instead of bitmaps as Leon suggested.
>> * v1: https://lore.kernel.org/all/20240906093444.3571619-10-huangjunxian6@xxxxxxxxxxxxx/
>> ---
>> drivers/infiniband/hw/hns/hns_roce_device.h | 11 +--
>> drivers/infiniband/hw/hns/hns_roce_hw_v2.c | 96 +++++++++++++++------
>> drivers/infiniband/hw/hns/hns_roce_hw_v2.h | 2 +-
>> drivers/infiniband/hw/hns/hns_roce_main.c | 2 -
>> drivers/infiniband/hw/hns/hns_roce_qp.c | 7 +-
>> 5 files changed, 74 insertions(+), 44 deletions(-)
>>
>> diff --git a/drivers/infiniband/hw/hns/hns_roce_device.h b/drivers/infiniband/hw/hns/hns_roce_device.h
>> index 9b51d5a1533f..560a1d9de408 100644
>> --- a/drivers/infiniband/hw/hns/hns_roce_device.h
>> +++ b/drivers/infiniband/hw/hns/hns_roce_device.h
>> @@ -489,12 +489,6 @@ struct hns_roce_bank {
>> u32 next; /* Next ID to allocate. */
>> };
>>
>> -struct hns_roce_idx_table {
>> - u32 *spare_idx;
>> - u32 head;
>> - u32 tail;
>> -};
>> -
>> struct hns_roce_qp_table {
>> struct hns_roce_hem_table qp_table;
>> struct hns_roce_hem_table irrl_table;
>> @@ -503,7 +497,7 @@ struct hns_roce_qp_table {
>> struct mutex scc_mutex;
>> struct hns_roce_bank bank[HNS_ROCE_QP_BANK_NUM];
>> struct mutex bank_mutex;
>> - struct hns_roce_idx_table idx_table;
>> + struct xarray dip_xa;
>> };
>>
>> struct hns_roce_cq_table {
>> @@ -658,6 +652,7 @@ struct hns_roce_qp {
>> u8 tc_mode;
>> u8 priority;
>> spinlock_t flush_lock;
>> + struct hns_roce_dip *dip;
>> };
>>
>> struct hns_roce_ib_iboe {
>> @@ -984,8 +979,6 @@ struct hns_roce_dev {
>> enum hns_roce_device_state state;
>> struct list_head qp_list; /* list of all qps on this dev */
>> spinlock_t qp_list_lock; /* protect qp_list */
>> - struct list_head dip_list; /* list of all dest ips on this dev */
>> - spinlock_t dip_list_lock; /* protect dip_list */
>>
>> struct list_head pgdir_list;
>> struct mutex pgdir_mutex;
>> diff --git a/drivers/infiniband/hw/hns/hns_roce_hw_v2.c b/drivers/infiniband/hw/hns/hns_roce_hw_v2.c
>> index d1c075fb0ad8..36e7cedfd106 100644
>> --- a/drivers/infiniband/hw/hns/hns_roce_hw_v2.c
>> +++ b/drivers/infiniband/hw/hns/hns_roce_hw_v2.c
>> @@ -2553,20 +2553,19 @@ static void hns_roce_free_link_table(struct hns_roce_dev *hr_dev)
>> free_link_table_buf(hr_dev, &priv->ext_llm);
>> }
>>
>> -static void free_dip_list(struct hns_roce_dev *hr_dev)
>> +static void free_dip_entry(struct hns_roce_dev *hr_dev)
>> {
>> struct hns_roce_dip *hr_dip;
>> - struct hns_roce_dip *tmp;
>> - unsigned long flags;
>> + unsigned long idx;
>>
>> - spin_lock_irqsave(&hr_dev->dip_list_lock, flags);
>> + xa_lock(&hr_dev->qp_table.dip_xa);
>
> In the original source code, spin_lock_irqsave is used, it means that irq is also taken into account. But in the new code, xa_lock is used. It means that irq is not taken into account. Not sure if this will introduce risks or not.
>
> Perhaps xa_lock_irqsave/xa_unlock_irqrestore is better?
>
The original spin_lock_irqsave() is kind of over-designed. Actually this code
doesn't involve racing with interrupts.
Junxian
> Zhu Yanjun
>
>>
>> - list_for_each_entry_safe(hr_dip, tmp, &hr_dev->dip_list, node) {
>> - list_del(&hr_dip->node);
>> + xa_for_each(&hr_dev->qp_table.dip_xa, idx, hr_dip) {
>> + __xa_erase(&hr_dev->qp_table.dip_xa, hr_dip->dip_idx);
>> kfree(hr_dip);
>> }
>>
>> - spin_unlock_irqrestore(&hr_dev->dip_list_lock, flags);
>> + xa_unlock(&hr_dev->qp_table.dip_xa);
>> }
>>
>> static struct ib_pd *free_mr_init_pd(struct hns_roce_dev *hr_dev)
>> @@ -2974,7 +2973,7 @@ static void hns_roce_v2_exit(struct hns_roce_dev *hr_dev)
>> hns_roce_free_link_table(hr_dev);
>>
>> if (hr_dev->pci_dev->revision == PCI_REVISION_ID_HIP09)
>> - free_dip_list(hr_dev);
>> + free_dip_entry(hr_dev);
>> }
>>
>> static int hns_roce_mbox_post(struct hns_roce_dev *hr_dev,
>> @@ -4694,26 +4693,49 @@ static int modify_qp_rtr_to_rts(struct ib_qp *ibqp, int attr_mask,
>> return 0;
>> }
>>
>> +static int alloc_dip_entry(struct xarray *dip_xa, u32 qpn)
>> +{
>> + struct hns_roce_dip *hr_dip;
>> + int ret;
>> +
>> + hr_dip = xa_load(dip_xa, qpn);
>> + if (hr_dip)
>> + return 0;
>> +
>> + hr_dip = kzalloc(sizeof(*hr_dip), GFP_KERNEL);
>> + if (!hr_dip)
>> + return -ENOMEM;
>> +
>> + ret = xa_err(xa_store(dip_xa, qpn, hr_dip, GFP_KERNEL));
>> + if (ret)
>> + kfree(hr_dip);
>> +
>> + return ret;
>> +}
>> +
>> static int get_dip_ctx_idx(struct ib_qp *ibqp, const struct ib_qp_attr *attr,
>> u32 *dip_idx)
>> {
>> const struct ib_global_route *grh = rdma_ah_read_grh(&attr->ah_attr);
>> struct hns_roce_dev *hr_dev = to_hr_dev(ibqp->device);
>> - u32 *spare_idx = hr_dev->qp_table.idx_table.spare_idx;
>> - u32 *head = &hr_dev->qp_table.idx_table.head;
>> - u32 *tail = &hr_dev->qp_table.idx_table.tail;
>> + struct xarray *dip_xa = &hr_dev->qp_table.dip_xa;
>> + struct hns_roce_qp *hr_qp = to_hr_qp(ibqp);
>> struct hns_roce_dip *hr_dip;
>> - unsigned long flags;
>> + unsigned long idx;
>> int ret = 0;
>>
>> - spin_lock_irqsave(&hr_dev->dip_list_lock, flags);
>> + ret = alloc_dip_entry(dip_xa, ibqp->qp_num);
>> + if (ret)
>> + return ret;
>>
>> - spare_idx[*tail] = ibqp->qp_num;
>> - *tail = (*tail == hr_dev->caps.num_qps - 1) ? 0 : (*tail + 1);
>> + xa_lock(dip_xa);
>>
>> - list_for_each_entry(hr_dip, &hr_dev->dip_list, node) {
>> - if (!memcmp(grh->dgid.raw, hr_dip->dgid, GID_LEN_V2)) {
>> + xa_for_each(dip_xa, idx, hr_dip) {
>> + if (hr_dip->qp_cnt &&
>> + !memcmp(grh->dgid.raw, hr_dip->dgid, GID_LEN_V2)) {
>> *dip_idx = hr_dip->dip_idx;
>> + hr_dip->qp_cnt++;
>> + hr_qp->dip = hr_dip;
>> goto out;
>> }
>> }
>> @@ -4721,19 +4743,24 @@ static int get_dip_ctx_idx(struct ib_qp *ibqp, const struct ib_qp_attr *attr,
>> /* If no dgid is found, a new dip and a mapping between dgid and
>> * dip_idx will be created.
>> */
>> - hr_dip = kzalloc(sizeof(*hr_dip), GFP_ATOMIC);
>> - if (!hr_dip) {
>> - ret = -ENOMEM;
>> - goto out;
>> + xa_for_each(dip_xa, idx, hr_dip) {
>> + if (hr_dip->qp_cnt)
>> + continue;
>> +
>> + *dip_idx = idx;
>> + memcpy(hr_dip->dgid, grh->dgid.raw, sizeof(grh->dgid.raw));
>> + hr_dip->dip_idx = idx;
>> + hr_dip->qp_cnt++;
>> + hr_qp->dip = hr_dip;
>> + break;
>> }
>>
>> - memcpy(hr_dip->dgid, grh->dgid.raw, sizeof(grh->dgid.raw));
>> - hr_dip->dip_idx = *dip_idx = spare_idx[*head];
>> - *head = (*head == hr_dev->caps.num_qps - 1) ? 0 : (*head + 1);
>> - list_add_tail(&hr_dip->node, &hr_dev->dip_list);
>> + /* This should never happen. */
>> + if (WARN_ON_ONCE(!hr_qp->dip))
>> + ret = -ENOSPC;
>>
>> out:
>> - spin_unlock_irqrestore(&hr_dev->dip_list_lock, flags);
>> + xa_unlock(dip_xa);
>> return ret;
>> }
>>
>> @@ -5587,6 +5614,20 @@ static int hns_roce_v2_destroy_qp_common(struct hns_roce_dev *hr_dev,
>> return ret;
>> }
>>
>> +static void put_dip_ctx_idx(struct hns_roce_dev *hr_dev,
>> + struct hns_roce_qp *hr_qp)
>> +{
>> + struct hns_roce_dip *hr_dip = hr_qp->dip;
>> +
>> + xa_lock(&hr_dev->qp_table.dip_xa);
>> +
>> + hr_dip->qp_cnt--;
>> + if (!hr_dip->qp_cnt)
>> + memset(hr_dip->dgid, 0, GID_LEN_V2);
>> +
>> + xa_unlock(&hr_dev->qp_table.dip_xa);
>> +}
>> +
>> int hns_roce_v2_destroy_qp(struct ib_qp *ibqp, struct ib_udata *udata)
>> {
>> struct hns_roce_dev *hr_dev = to_hr_dev(ibqp->device);
>> @@ -5600,6 +5641,9 @@ int hns_roce_v2_destroy_qp(struct ib_qp *ibqp, struct ib_udata *udata)
>> spin_unlock_irqrestore(&hr_qp->flush_lock, flags);
>> flush_work(&hr_qp->flush_work.work);
>>
>> + if (hr_qp->cong_type == CONG_TYPE_DIP)
>> + put_dip_ctx_idx(hr_dev, hr_qp);
>> +
>> ret = hns_roce_v2_destroy_qp_common(hr_dev, hr_qp, udata);
>> if (ret)
>> ibdev_err_ratelimited(&hr_dev->ib_dev,
>> diff --git a/drivers/infiniband/hw/hns/hns_roce_hw_v2.h b/drivers/infiniband/hw/hns/hns_roce_hw_v2.h
>> index 3b3c6259ace0..1c593fcf1143 100644
>> --- a/drivers/infiniband/hw/hns/hns_roce_hw_v2.h
>> +++ b/drivers/infiniband/hw/hns/hns_roce_hw_v2.h
>> @@ -1347,7 +1347,7 @@ struct hns_roce_v2_priv {
>> struct hns_roce_dip {
>> u8 dgid[GID_LEN_V2];
>> u32 dip_idx;
>> - struct list_head node; /* all dips are on a list */
>> + u32 qp_cnt;
>> };
>>
>> struct fmea_ram_ecc {
>> diff --git a/drivers/infiniband/hw/hns/hns_roce_main.c b/drivers/infiniband/hw/hns/hns_roce_main.c
>> index 49315f39361d..ae24c81c9812 100644
>> --- a/drivers/infiniband/hw/hns/hns_roce_main.c
>> +++ b/drivers/infiniband/hw/hns/hns_roce_main.c
>> @@ -1135,8 +1135,6 @@ int hns_roce_init(struct hns_roce_dev *hr_dev)
>>
>> INIT_LIST_HEAD(&hr_dev->qp_list);
>> spin_lock_init(&hr_dev->qp_list_lock);
>> - INIT_LIST_HEAD(&hr_dev->dip_list);
>> - spin_lock_init(&hr_dev->dip_list_lock);
>>
>> ret = hns_roce_register_device(hr_dev);
>> if (ret)
>> diff --git a/drivers/infiniband/hw/hns/hns_roce_qp.c b/drivers/infiniband/hw/hns/hns_roce_qp.c
>> index 2ad03ecdbf8e..7d67cefe549c 100644
>> --- a/drivers/infiniband/hw/hns/hns_roce_qp.c
>> +++ b/drivers/infiniband/hw/hns/hns_roce_qp.c
>> @@ -1573,14 +1573,10 @@ int hns_roce_init_qp_table(struct hns_roce_dev *hr_dev)
>> unsigned int reserved_from_bot;
>> unsigned int i;
>>
>> - qp_table->idx_table.spare_idx = kcalloc(hr_dev->caps.num_qps,
>> - sizeof(u32), GFP_KERNEL);
>> - if (!qp_table->idx_table.spare_idx)
>> - return -ENOMEM;
>> -
>> mutex_init(&qp_table->scc_mutex);
>> mutex_init(&qp_table->bank_mutex);
>> xa_init(&hr_dev->qp_table_xa);
>> + xa_init(&qp_table->dip_xa);
>>
>> reserved_from_bot = hr_dev->caps.reserved_qps;
>>
>> @@ -1607,5 +1603,4 @@ void hns_roce_cleanup_qp_table(struct hns_roce_dev *hr_dev)
>> ida_destroy(&hr_dev->qp_table.bank[i].ida);
>> mutex_destroy(&hr_dev->qp_table.bank_mutex);
>> mutex_destroy(&hr_dev->qp_table.scc_mutex);
>> - kfree(hr_dev->qp_table.idx_table.spare_idx);
>> }
>> --
>> 2.33.0
>>
>
