On Tue, Mar 17, 2020 at 03:40:26PM +0200, Max Gurtovoy wrote:
> ULP's can use this API to create/destroy SRQ's with the same
> characteristics for implementing a logic that aimed to save resources
> without significant performance penalty (e.g. create SRQ per completion
> vector and use shared receive buffers for multiple controllers of the
> ULP).
>
> Signed-off-by: Max Gurtovoy <maxg@xxxxxxxxxxxx>
> ---
> drivers/infiniband/core/Makefile | 2 +-
> drivers/infiniband/core/srq_set.c | 78 +++++++++++++++++++++++++++++++++++++++
> drivers/infiniband/core/verbs.c | 4 ++
> include/rdma/ib_verbs.h | 5 +++
> include/rdma/srq_set.h | 18 +++++++++
> 5 files changed, 106 insertions(+), 1 deletion(-)
> create mode 100644 drivers/infiniband/core/srq_set.c
> create mode 100644 include/rdma/srq_set.h
>
> diff --git a/drivers/infiniband/core/Makefile b/drivers/infiniband/core/Makefile
> index d1b14887..1d3eaec 100644
> --- a/drivers/infiniband/core/Makefile
> +++ b/drivers/infiniband/core/Makefile
> @@ -12,7 +12,7 @@ ib_core-y := packer.o ud_header.o verbs.o cq.o rw.o sysfs.o \
> roce_gid_mgmt.o mr_pool.o addr.o sa_query.o \
> multicast.o mad.o smi.o agent.o mad_rmpp.o \
> nldev.o restrack.o counters.o ib_core_uverbs.o \
> - trace.o
> + trace.o srq_set.o
Why did you call it "srq_set.c" and not "srq.c"?
>
> ib_core-$(CONFIG_SECURITY_INFINIBAND) += security.o
> ib_core-$(CONFIG_CGROUP_RDMA) += cgroup.o
> diff --git a/drivers/infiniband/core/srq_set.c b/drivers/infiniband/core/srq_set.c
> new file mode 100644
> index 0000000..d143561
> --- /dev/null
> +++ b/drivers/infiniband/core/srq_set.c
> @@ -0,0 +1,78 @@
> +// SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB
> +/*
> + * Copyright (c) 2020 Mellanox Technologies. All rights reserved.
> + */
> +
> +#include <rdma/srq_set.h>
> +
> +struct ib_srq *rdma_srq_get(struct ib_pd *pd)
> +{
> + struct ib_srq *srq;
> + unsigned long flags;
> +
> + spin_lock_irqsave(&pd->srq_lock, flags);
> + srq = list_first_entry_or_null(&pd->srqs, struct ib_srq, pd_entry);
> + if (srq) {
> + list_del(&srq->pd_entry);
> + pd->srqs_used++;
I don't see any real usage of srqs_used.
> + }
> + spin_unlock_irqrestore(&pd->srq_lock, flags);
> +
> + return srq;
> +}
> +EXPORT_SYMBOL(rdma_srq_get);
> +
> +void rdma_srq_put(struct ib_pd *pd, struct ib_srq *srq)
> +{
> + unsigned long flags;
> +
> + spin_lock_irqsave(&pd->srq_lock, flags);
> + list_add(&srq->pd_entry, &pd->srqs);
> + pd->srqs_used--;
> + spin_unlock_irqrestore(&pd->srq_lock, flags);
> +}
> +EXPORT_SYMBOL(rdma_srq_put);
> +
> +int rdma_srq_set_init(struct ib_pd *pd, int nr,
> + struct ib_srq_init_attr *srq_attr)
> +{
> + struct ib_srq *srq;
> + unsigned long flags;
> + int ret, i;
> +
> + for (i = 0; i < nr; i++) {
> + srq = ib_create_srq(pd, srq_attr);
> + if (IS_ERR(srq)) {
> + ret = PTR_ERR(srq);
> + goto out;
> + }
> +
> + spin_lock_irqsave(&pd->srq_lock, flags);
> + list_add_tail(&srq->pd_entry, &pd->srqs);
> + spin_unlock_irqrestore(&pd->srq_lock, flags);
> + }
> +
> + return 0;
> +out:
> + rdma_srq_set_destroy(pd);
> + return ret;
> +}
> +EXPORT_SYMBOL(rdma_srq_set_init);
> +
> +void rdma_srq_set_destroy(struct ib_pd *pd)
> +{
> + struct ib_srq *srq;
> + unsigned long flags;
> +
> + spin_lock_irqsave(&pd->srq_lock, flags);
> + while (!list_empty(&pd->srqs)) {
> + srq = list_first_entry(&pd->srqs, struct ib_srq, pd_entry);
> + list_del(&srq->pd_entry);
> +
> + spin_unlock_irqrestore(&pd->srq_lock, flags);
> + ib_destroy_srq(srq);
> + spin_lock_irqsave(&pd->srq_lock, flags);
> + }
> + spin_unlock_irqrestore(&pd->srq_lock, flags);
> +}
> +EXPORT_SYMBOL(rdma_srq_set_destroy);
> diff --git a/drivers/infiniband/core/verbs.c b/drivers/infiniband/core/verbs.c
> index e62c9df..6950abf 100644
> --- a/drivers/infiniband/core/verbs.c
> +++ b/drivers/infiniband/core/verbs.c
> @@ -272,6 +272,9 @@ struct ib_pd *__ib_alloc_pd(struct ib_device *device, unsigned int flags,
> pd->__internal_mr = NULL;
> atomic_set(&pd->usecnt, 0);
> pd->flags = flags;
> + pd->srqs_used = 0;
> + spin_lock_init(&pd->srq_lock);
> + INIT_LIST_HEAD(&pd->srqs);
>
> pd->res.type = RDMA_RESTRACK_PD;
> rdma_restrack_set_task(&pd->res, caller);
> @@ -340,6 +343,7 @@ void ib_dealloc_pd_user(struct ib_pd *pd, struct ib_udata *udata)
> pd->__internal_mr = NULL;
> }
>
> + WARN_ON_ONCE(pd->srqs_used > 0);
It can be achieved by WARN_ON_ONCE(!list_empty(&pd->srqs))
> /* uverbs manipulates usecnt with proper locking, while the kabi
> requires the caller to guarantee we can't race here. */
> WARN_ON(atomic_read(&pd->usecnt));
> diff --git a/include/rdma/ib_verbs.h b/include/rdma/ib_verbs.h
> index 1f779fa..fc8207d 100644
> --- a/include/rdma/ib_verbs.h
> +++ b/include/rdma/ib_verbs.h
> @@ -1517,6 +1517,10 @@ struct ib_pd {
>
> u32 unsafe_global_rkey;
>
> + spinlock_t srq_lock;
> + int srqs_used;
> + struct list_head srqs;
> +
> /*
> * Implementation details of the RDMA core, don't use in drivers:
> */
> @@ -1585,6 +1589,7 @@ struct ib_srq {
> void *srq_context;
> enum ib_srq_type srq_type;
> atomic_t usecnt;
> + struct list_head pd_entry; /* srq set entry */
>
> struct {
> struct ib_cq *cq;
> diff --git a/include/rdma/srq_set.h b/include/rdma/srq_set.h
> new file mode 100644
> index 0000000..834c4c6
> --- /dev/null
> +++ b/include/rdma/srq_set.h
> @@ -0,0 +1,18 @@
> +/* SPDX-License-Identifier: (GPL-2.0 OR Linux-OpenIB) */
> +/*
> + * Copyright (c) 2020 Mellanox Technologies. All rights reserved.
> + */
> +
> +#ifndef _RDMA_SRQ_SET_H
> +#define _RDMA_SRQ_SET_H 1
"1" is not needed.
> +
> +#include <rdma/ib_verbs.h>
> +
> +struct ib_srq *rdma_srq_get(struct ib_pd *pd);
> +void rdma_srq_put(struct ib_pd *pd, struct ib_srq *srq);
At the end, it is not get/put semantics but more add/remove.
Thanks
> +
> +int rdma_srq_set_init(struct ib_pd *pd, int nr,
> + struct ib_srq_init_attr *srq_attr);
> +void rdma_srq_set_destroy(struct ib_pd *pd);
> +
> +#endif /* _RDMA_SRQ_SET_H */
> --
> 1.8.3.1
>
