public inbox for linux-rdma@vger.kernel.org
 help / color / mirror / Atom feed
* [PATCH for-next 0/4] Introduce Completion Counters
@ 2026-04-07 11:54 Michael Margolin
  2026-04-07 11:54 ` [PATCH for-next 1/4] RDMA/core: Add Completion Counters support Michael Margolin
                   ` (3 more replies)
  0 siblings, 4 replies; 14+ messages in thread
From: Michael Margolin @ 2026-04-07 11:54 UTC (permalink / raw)
  To: jgg, leon, linux-rdma; +Cc: sleybo, matua, gal.pressman

Add core infrastructure for Completion Counters, a light-weight
alternative to polling CQ for tracking operation completions. The
related rdma-core interface proposal is linked in [1].

Define the UVERBS_OBJECT_COMP_CNTR ioctl object with create, destroy,
set, inc and read methods for both success and error counters. Add a
QP attach method on the QP object to associate a completion counter
with a queue pair.

Completion Counters can be backed by user-provided VA or dmabuf or by
internal device/driver memory. Common command infrastructure allows any
of the implementations to support the various device capabilities.

Add EFA Completion Counters support as first implementer.

[1] https://github.com/linux-rdma/rdma-core/pull/1701

Michael Margolin (4):
  RDMA/core: Add Completion Counters support
  RDMA/core: Add Completion Counters to resource tracking
  RDMA/efa: Update device interface
  RDMA/efa: Add Completion Counters support

 drivers/infiniband/core/Makefile              |   1 +
 drivers/infiniband/core/device.c              |  10 +
 drivers/infiniband/core/nldev.c               |   1 +
 drivers/infiniband/core/rdma_core.h           |   1 +
 drivers/infiniband/core/restrack.c            |   2 +
 drivers/infiniband/core/uverbs_cmd.c          |   1 +
 .../core/uverbs_std_types_comp_cntr.c         | 379 ++++++++++++++++++
 drivers/infiniband/core/uverbs_std_types_qp.c |  45 ++-
 drivers/infiniband/core/uverbs_uapi.c         |   1 +
 drivers/infiniband/hw/efa/efa.h               |  15 +
 .../infiniband/hw/efa/efa_admin_cmds_defs.h   | 185 ++++++++-
 drivers/infiniband/hw/efa/efa_com_cmd.c       | 106 +++++
 drivers/infiniband/hw/efa/efa_com_cmd.h       |  36 ++
 drivers/infiniband/hw/efa/efa_io_defs.h       |  62 ++-
 drivers/infiniband/hw/efa/efa_main.c          |   8 +
 drivers/infiniband/hw/efa/efa_verbs.c         | 177 ++++++++
 include/rdma/ib_verbs.h                       |  27 ++
 include/rdma/restrack.h                       |   4 +
 include/uapi/rdma/efa-abi.h                   |   1 +
 include/uapi/rdma/ib_user_ioctl_cmds.h        |  65 +++
 include/uapi/rdma/ib_user_ioctl_verbs.h       |   9 +
 include/uapi/rdma/ib_user_verbs.h             |   2 +-
 22 files changed, 1131 insertions(+), 7 deletions(-)
 create mode 100644 drivers/infiniband/core/uverbs_std_types_comp_cntr.c

-- 
2.47.3


^ permalink raw reply	[flat|nested] 14+ messages in thread

* [PATCH for-next 1/4] RDMA/core: Add Completion Counters support
  2026-04-07 11:54 [PATCH for-next 0/4] Introduce Completion Counters Michael Margolin
@ 2026-04-07 11:54 ` Michael Margolin
  2026-04-07 14:17   ` Jason Gunthorpe
  2026-04-07 11:54 ` [PATCH for-next 2/4] RDMA/core: Add Completion Counters to resource tracking Michael Margolin
                   ` (2 subsequent siblings)
  3 siblings, 1 reply; 14+ messages in thread
From: Michael Margolin @ 2026-04-07 11:54 UTC (permalink / raw)
  To: jgg, leon, linux-rdma; +Cc: sleybo, matua, gal.pressman, Yonatan Nachum

Add core infrastructure for Completion Counters, a light-weight
alternative to polling CQ for tracking operation completions.

Define the UVERBS_OBJECT_COMP_CNTR ioctl object with create, destroy,
set, inc and read methods for both success and error counters. Add a
QP attach method on the QP object to associate a completion counter
with a queue pair.

The create handler constructs umem from user-provided VA or dmabuf for
each counter, following the CQ buffer pattern. Set, inc and read
handlers pass through to driver callbacks. The QP attach handler
validates the operation mask flags and delegates to the driver.

Add ib_comp_cntr struct, ib_comp_cntr_attach_attr, device ops, and
DECLARE_RDMA_OBJ_SIZE for driver object allocation.

Only userspace Completion Counters are supported at this stage.

Reviewed-by: Yonatan Nachum <ynachum@amazon.com>
Signed-off-by: Michael Margolin <mrgolin@amazon.com>
---
 drivers/infiniband/core/Makefile              |   1 +
 drivers/infiniband/core/device.c              |  10 +
 drivers/infiniband/core/rdma_core.h           |   1 +
 drivers/infiniband/core/uverbs_cmd.c          |   1 +
 .../core/uverbs_std_types_comp_cntr.c         | 373 ++++++++++++++++++
 drivers/infiniband/core/uverbs_std_types_qp.c |  45 ++-
 drivers/infiniband/core/uverbs_uapi.c         |   1 +
 include/rdma/ib_verbs.h                       |  26 ++
 include/uapi/rdma/ib_user_ioctl_cmds.h        |  65 +++
 include/uapi/rdma/ib_user_ioctl_verbs.h       |   9 +
 include/uapi/rdma/ib_user_verbs.h             |   2 +-
 11 files changed, 532 insertions(+), 2 deletions(-)
 create mode 100644 drivers/infiniband/core/uverbs_std_types_comp_cntr.c

diff --git a/drivers/infiniband/core/Makefile b/drivers/infiniband/core/Makefile
index dce798d8cfe6..4767339608a1 100644
--- a/drivers/infiniband/core/Makefile
+++ b/drivers/infiniband/core/Makefile
@@ -35,6 +35,7 @@ ib_umad-y :=			user_mad.o
 ib_uverbs-y :=			uverbs_main.o uverbs_cmd.o uverbs_marshall.o \
 				rdma_core.o uverbs_std_types.o uverbs_ioctl.o \
 				uverbs_std_types_cq.o \
+				uverbs_std_types_comp_cntr.o \
 				uverbs_std_types_dmabuf.o \
 				uverbs_std_types_dmah.o \
 				uverbs_std_types_flow_action.o uverbs_std_types_dm.o \
diff --git a/drivers/infiniband/core/device.c b/drivers/infiniband/core/device.c
index 4c174f7f1070..c9b4a85d1a35 100644
--- a/drivers/infiniband/core/device.c
+++ b/drivers/infiniband/core/device.c
@@ -2733,6 +2733,7 @@ void ib_set_device_ops(struct ib_device *dev, const struct ib_device_ops *ops)
 	SET_DEVICE_OP(dev_ops, create_ah);
 	SET_DEVICE_OP(dev_ops, create_counters);
 	SET_DEVICE_OP(dev_ops, create_cq);
+	SET_DEVICE_OP(dev_ops, create_comp_cntr);
 	SET_DEVICE_OP(dev_ops, create_user_cq);
 	SET_DEVICE_OP(dev_ops, create_flow);
 	SET_DEVICE_OP(dev_ops, create_qp);
@@ -2753,6 +2754,7 @@ void ib_set_device_ops(struct ib_device *dev, const struct ib_device_ops *ops)
 	SET_DEVICE_OP(dev_ops, destroy_ah);
 	SET_DEVICE_OP(dev_ops, destroy_counters);
 	SET_DEVICE_OP(dev_ops, destroy_cq);
+	SET_DEVICE_OP(dev_ops, destroy_comp_cntr);
 	SET_DEVICE_OP(dev_ops, destroy_flow);
 	SET_DEVICE_OP(dev_ops, destroy_flow_action);
 	SET_DEVICE_OP(dev_ops, destroy_qp);
@@ -2804,6 +2806,9 @@ void ib_set_device_ops(struct ib_device *dev, const struct ib_device_ops *ops)
 	SET_DEVICE_OP(dev_ops, modify_hw_stat);
 	SET_DEVICE_OP(dev_ops, modify_port);
 	SET_DEVICE_OP(dev_ops, modify_qp);
+	SET_DEVICE_OP(dev_ops, inc_comp_cntr);
+	SET_DEVICE_OP(dev_ops, inc_err_comp_cntr);
+	SET_DEVICE_OP(dev_ops, qp_attach_comp_cntr);
 	SET_DEVICE_OP(dev_ops, modify_srq);
 	SET_DEVICE_OP(dev_ops, modify_wq);
 	SET_DEVICE_OP(dev_ops, peek_cq);
@@ -2827,12 +2832,16 @@ void ib_set_device_ops(struct ib_device *dev, const struct ib_device_ops *ops)
 	SET_DEVICE_OP(dev_ops, query_ucontext);
 	SET_DEVICE_OP(dev_ops, rdma_netdev_get_params);
 	SET_DEVICE_OP(dev_ops, read_counters);
+	SET_DEVICE_OP(dev_ops, read_comp_cntr);
+	SET_DEVICE_OP(dev_ops, read_err_comp_cntr);
 	SET_DEVICE_OP(dev_ops, reg_dm_mr);
 	SET_DEVICE_OP(dev_ops, reg_user_mr);
 	SET_DEVICE_OP(dev_ops, reg_user_mr_dmabuf);
 	SET_DEVICE_OP(dev_ops, req_notify_cq);
 	SET_DEVICE_OP(dev_ops, rereg_user_mr);
 	SET_DEVICE_OP(dev_ops, resize_user_cq);
+	SET_DEVICE_OP(dev_ops, set_comp_cntr);
+	SET_DEVICE_OP(dev_ops, set_err_comp_cntr);
 	SET_DEVICE_OP(dev_ops, set_vf_guid);
 	SET_DEVICE_OP(dev_ops, set_vf_link_state);
 	SET_DEVICE_OP(dev_ops, ufile_hw_cleanup);
@@ -2841,6 +2850,7 @@ void ib_set_device_ops(struct ib_device *dev, const struct ib_device_ops *ops)
 	SET_OBJ_SIZE(dev_ops, ib_ah);
 	SET_OBJ_SIZE(dev_ops, ib_counters);
 	SET_OBJ_SIZE(dev_ops, ib_cq);
+	SET_OBJ_SIZE(dev_ops, ib_comp_cntr);
 	SET_OBJ_SIZE(dev_ops, ib_dmah);
 	SET_OBJ_SIZE(dev_ops, ib_mw);
 	SET_OBJ_SIZE(dev_ops, ib_pd);
diff --git a/drivers/infiniband/core/rdma_core.h b/drivers/infiniband/core/rdma_core.h
index 269b393799ab..2569550e4c6d 100644
--- a/drivers/infiniband/core/rdma_core.h
+++ b/drivers/infiniband/core/rdma_core.h
@@ -156,6 +156,7 @@ uverbs_api_ioctl_handler_fn uverbs_get_handler_fn(struct ib_udata *udata);
 
 extern const struct uapi_definition uverbs_def_obj_async_fd[];
 extern const struct uapi_definition uverbs_def_obj_counters[];
+extern const struct uapi_definition uverbs_def_obj_comp_cntr[];
 extern const struct uapi_definition uverbs_def_obj_cq[];
 extern const struct uapi_definition uverbs_def_obj_device[];
 extern const struct uapi_definition uverbs_def_obj_dm[];
diff --git a/drivers/infiniband/core/uverbs_cmd.c b/drivers/infiniband/core/uverbs_cmd.c
index a768436ba468..4bc493b3b624 100644
--- a/drivers/infiniband/core/uverbs_cmd.c
+++ b/drivers/infiniband/core/uverbs_cmd.c
@@ -3673,6 +3673,7 @@ static int ib_uverbs_ex_query_device(struct uverbs_attr_bundle *attrs)
 	resp.cq_moderation_caps.max_cq_moderation_period =
 		attr.cq_caps.max_cq_moderation_period;
 	resp.max_dm_size = attr.max_dm_size;
+	resp.max_comp_cntr = attr.max_comp_cntr;
 	resp.response_length = uverbs_response_length(attrs, sizeof(resp));
 
 	return uverbs_response(attrs, &resp, sizeof(resp));
diff --git a/drivers/infiniband/core/uverbs_std_types_comp_cntr.c b/drivers/infiniband/core/uverbs_std_types_comp_cntr.c
new file mode 100644
index 000000000000..a62c20d4e5a4
--- /dev/null
+++ b/drivers/infiniband/core/uverbs_std_types_comp_cntr.c
@@ -0,0 +1,373 @@
+// SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB
+/*
+ * Copyright Amazon.com, Inc. or its affiliates. All rights reserved.
+ */
+
+#include <rdma/uverbs_std_types.h>
+#include <rdma/ib_umem.h>
+#include <rdma/ib_umem_dmabuf.h>
+#include "rdma_core.h"
+#include "uverbs.h"
+
+static int uverbs_free_comp_cntr(struct ib_uobject *uobject,
+				 enum rdma_remove_reason why,
+				 struct uverbs_attr_bundle *attrs)
+{
+	struct ib_comp_cntr *cc = uobject->object;
+	int ret;
+
+	ret = cc->device->ops.destroy_comp_cntr(cc);
+	if (ret)
+		return ret;
+
+	ib_umem_release(cc->comp_umem);
+	ib_umem_release(cc->err_umem);
+	kfree(cc);
+	return 0;
+}
+
+static int comp_cntr_get_umem(struct ib_device *ib_dev,
+			      struct uverbs_attr_bundle *attrs,
+			      int va_attr, int fd_attr, int offset_attr,
+			      struct ib_umem **umem_out)
+{
+	struct ib_umem_dmabuf *umem_dmabuf;
+	u64 buffer_offset;
+	u64 buffer_va;
+	int buffer_fd;
+	int ret;
+
+	*umem_out = NULL;
+
+	if (uverbs_attr_is_valid(attrs, va_attr)) {
+		if (uverbs_attr_is_valid(attrs, fd_attr) ||
+		    uverbs_attr_is_valid(attrs, offset_attr))
+			return -EINVAL;
+
+		ret = uverbs_copy_from(&buffer_va, attrs, va_attr);
+		if (ret)
+			return ret;
+
+		*umem_out = ib_umem_get(ib_dev, buffer_va, sizeof(u64),
+					IB_ACCESS_LOCAL_WRITE);
+		if (IS_ERR(*umem_out)) {
+			ret = PTR_ERR(*umem_out);
+			*umem_out = NULL;
+			return ret;
+		}
+	} else if (uverbs_attr_is_valid(attrs, fd_attr)) {
+		if (uverbs_attr_is_valid(attrs, va_attr))
+			return -EINVAL;
+
+		ret = uverbs_get_raw_fd(&buffer_fd, attrs, fd_attr);
+		if (ret)
+			return ret;
+
+		ret = uverbs_copy_from(&buffer_offset, attrs, offset_attr);
+		if (ret)
+			return ret;
+
+		umem_dmabuf = ib_umem_dmabuf_get_pinned(ib_dev, buffer_offset,
+							sizeof(u64), buffer_fd,
+							IB_ACCESS_LOCAL_WRITE);
+		if (IS_ERR(umem_dmabuf))
+			return PTR_ERR(umem_dmabuf);
+
+		*umem_out = &umem_dmabuf->umem;
+	}
+
+	return 0;
+}
+
+static int UVERBS_HANDLER(UVERBS_METHOD_COMP_CNTR_CREATE)(
+	struct uverbs_attr_bundle *attrs)
+{
+	struct ib_uobject *uobj = uverbs_attr_get_uobject(
+		attrs, UVERBS_ATTR_CREATE_COMP_CNTR_HANDLE);
+	struct ib_device *ib_dev = attrs->context->device;
+	struct ib_comp_cntr *cc;
+	int ret;
+
+	if (!ib_dev->ops.create_comp_cntr ||
+	    !ib_dev->ops.destroy_comp_cntr ||
+	    !ib_dev->ops.qp_attach_comp_cntr)
+		return -EOPNOTSUPP;
+
+	cc = rdma_zalloc_drv_obj(ib_dev, ib_comp_cntr);
+	if (!cc)
+		return -ENOMEM;
+
+	cc->device = ib_dev;
+	cc->uobject = uobj;
+
+	ret = comp_cntr_get_umem(ib_dev, attrs,
+				 UVERBS_ATTR_CREATE_COMP_CNTR_BUFFER_VA,
+				 UVERBS_ATTR_CREATE_COMP_CNTR_BUFFER_FD,
+				 UVERBS_ATTR_CREATE_COMP_CNTR_BUFFER_OFFSET,
+				 &cc->comp_umem);
+	if (ret)
+		goto err_free;
+
+	ret = comp_cntr_get_umem(ib_dev, attrs,
+				 UVERBS_ATTR_CREATE_COMP_CNTR_ERR_BUFFER_VA,
+				 UVERBS_ATTR_CREATE_COMP_CNTR_ERR_BUFFER_FD,
+				 UVERBS_ATTR_CREATE_COMP_CNTR_ERR_BUFFER_OFFSET,
+				 &cc->err_umem);
+	if (ret)
+		goto err_comp_umem;
+
+	ret = ib_dev->ops.create_comp_cntr(cc, attrs);
+	if (ret)
+		goto err_err_umem;
+
+	uobj->object = cc;
+	uverbs_finalize_uobj_create(attrs, UVERBS_ATTR_CREATE_COMP_CNTR_HANDLE);
+
+	ret = uverbs_copy_to(attrs,
+			     UVERBS_ATTR_CREATE_COMP_CNTR_RESP_COUNT_MAX_VALUE,
+			     &cc->comp_count_max_value,
+			     sizeof(cc->comp_count_max_value));
+	if (ret)
+		return ret;
+
+	ret = uverbs_copy_to(attrs,
+			     UVERBS_ATTR_CREATE_COMP_CNTR_RESP_ERR_COUNT_MAX_VALUE,
+			     &cc->err_count_max_value,
+			     sizeof(cc->err_count_max_value));
+	return ret;
+
+err_err_umem:
+	ib_umem_release(cc->err_umem);
+err_comp_umem:
+	ib_umem_release(cc->comp_umem);
+err_free:
+	kfree(cc);
+	return ret;
+}
+
+static int UVERBS_HANDLER(UVERBS_METHOD_COMP_CNTR_SET)(
+	struct uverbs_attr_bundle *attrs)
+{
+	struct ib_comp_cntr *cc = uverbs_attr_get_obj(
+		attrs, UVERBS_ATTR_SET_COMP_CNTR_HANDLE);
+	u64 value;
+	int ret;
+
+	if (!cc->device->ops.set_comp_cntr)
+		return -EOPNOTSUPP;
+
+	ret = uverbs_copy_from(&value, attrs, UVERBS_ATTR_SET_COMP_CNTR_VALUE);
+	if (ret)
+		return ret;
+
+	return cc->device->ops.set_comp_cntr(cc, value);
+}
+
+static int UVERBS_HANDLER(UVERBS_METHOD_COMP_CNTR_SET_ERR)(
+	struct uverbs_attr_bundle *attrs)
+{
+	struct ib_comp_cntr *cc = uverbs_attr_get_obj(
+		attrs, UVERBS_ATTR_SET_ERR_COMP_CNTR_HANDLE);
+	u64 value;
+	int ret;
+
+	if (!cc->device->ops.set_err_comp_cntr)
+		return -EOPNOTSUPP;
+
+	ret = uverbs_copy_from(&value, attrs,
+			       UVERBS_ATTR_SET_ERR_COMP_CNTR_VALUE);
+	if (ret)
+		return ret;
+
+	return cc->device->ops.set_err_comp_cntr(cc, value);
+}
+
+static int UVERBS_HANDLER(UVERBS_METHOD_COMP_CNTR_INC)(
+	struct uverbs_attr_bundle *attrs)
+{
+	struct ib_comp_cntr *cc = uverbs_attr_get_obj(
+		attrs, UVERBS_ATTR_INC_COMP_CNTR_HANDLE);
+	u64 amount;
+	int ret;
+
+	if (!cc->device->ops.inc_comp_cntr)
+		return -EOPNOTSUPP;
+
+	ret = uverbs_copy_from(&amount, attrs, UVERBS_ATTR_INC_COMP_CNTR_VALUE);
+	if (ret)
+		return ret;
+
+	return cc->device->ops.inc_comp_cntr(cc, amount);
+}
+
+static int UVERBS_HANDLER(UVERBS_METHOD_COMP_CNTR_INC_ERR)(
+	struct uverbs_attr_bundle *attrs)
+{
+	struct ib_comp_cntr *cc = uverbs_attr_get_obj(
+		attrs, UVERBS_ATTR_INC_ERR_COMP_CNTR_HANDLE);
+	u64 amount;
+	int ret;
+
+	if (!cc->device->ops.inc_err_comp_cntr)
+		return -EOPNOTSUPP;
+
+	ret = uverbs_copy_from(&amount, attrs,
+			       UVERBS_ATTR_INC_ERR_COMP_CNTR_VALUE);
+	if (ret)
+		return ret;
+
+	return cc->device->ops.inc_err_comp_cntr(cc, amount);
+}
+
+static int UVERBS_HANDLER(UVERBS_METHOD_COMP_CNTR_READ)(
+	struct uverbs_attr_bundle *attrs)
+{
+	struct ib_comp_cntr *cc = uverbs_attr_get_obj(
+		attrs, UVERBS_ATTR_READ_COMP_CNTR_HANDLE);
+	u64 value;
+	int ret;
+
+	if (!cc->device->ops.read_comp_cntr)
+		return -EOPNOTSUPP;
+
+	ret = cc->device->ops.read_comp_cntr(cc, &value);
+	if (ret)
+		return ret;
+
+	return uverbs_copy_to(attrs, UVERBS_ATTR_READ_COMP_CNTR_RESP_VALUE,
+			      &value, sizeof(value));
+}
+
+static int UVERBS_HANDLER(UVERBS_METHOD_COMP_CNTR_READ_ERR)(
+	struct uverbs_attr_bundle *attrs)
+{
+	struct ib_comp_cntr *cc = uverbs_attr_get_obj(
+		attrs, UVERBS_ATTR_READ_ERR_COMP_CNTR_HANDLE);
+	u64 value;
+	int ret;
+
+	if (!cc->device->ops.read_err_comp_cntr)
+		return -EOPNOTSUPP;
+
+	ret = cc->device->ops.read_err_comp_cntr(cc, &value);
+	if (ret)
+		return ret;
+
+	return uverbs_copy_to(attrs, UVERBS_ATTR_READ_ERR_COMP_CNTR_RESP_VALUE,
+			      &value, sizeof(value));
+}
+
+DECLARE_UVERBS_NAMED_METHOD(
+	UVERBS_METHOD_COMP_CNTR_CREATE,
+	UVERBS_ATTR_IDR(UVERBS_ATTR_CREATE_COMP_CNTR_HANDLE,
+			UVERBS_OBJECT_COMP_CNTR,
+			UVERBS_ACCESS_NEW,
+			UA_MANDATORY),
+	UVERBS_ATTR_PTR_IN(UVERBS_ATTR_CREATE_COMP_CNTR_BUFFER_VA,
+			   UVERBS_ATTR_TYPE(u64),
+			   UA_OPTIONAL),
+	UVERBS_ATTR_RAW_FD(UVERBS_ATTR_CREATE_COMP_CNTR_BUFFER_FD,
+			   UA_OPTIONAL),
+	UVERBS_ATTR_PTR_IN(UVERBS_ATTR_CREATE_COMP_CNTR_BUFFER_OFFSET,
+			   UVERBS_ATTR_TYPE(u64),
+			   UA_OPTIONAL),
+	UVERBS_ATTR_PTR_IN(UVERBS_ATTR_CREATE_COMP_CNTR_ERR_BUFFER_VA,
+			   UVERBS_ATTR_TYPE(u64),
+			   UA_OPTIONAL),
+	UVERBS_ATTR_RAW_FD(UVERBS_ATTR_CREATE_COMP_CNTR_ERR_BUFFER_FD,
+			   UA_OPTIONAL),
+	UVERBS_ATTR_PTR_IN(UVERBS_ATTR_CREATE_COMP_CNTR_ERR_BUFFER_OFFSET,
+			   UVERBS_ATTR_TYPE(u64),
+			   UA_OPTIONAL),
+	UVERBS_ATTR_PTR_OUT(UVERBS_ATTR_CREATE_COMP_CNTR_RESP_COUNT_MAX_VALUE,
+			    UVERBS_ATTR_TYPE(u64),
+			    UA_MANDATORY),
+	UVERBS_ATTR_PTR_OUT(UVERBS_ATTR_CREATE_COMP_CNTR_RESP_ERR_COUNT_MAX_VALUE,
+			    UVERBS_ATTR_TYPE(u64),
+			    UA_MANDATORY),
+	UVERBS_ATTR_UHW());
+
+DECLARE_UVERBS_NAMED_METHOD_DESTROY(
+	UVERBS_METHOD_COMP_CNTR_DESTROY,
+	UVERBS_ATTR_IDR(UVERBS_ATTR_DESTROY_COMP_CNTR_HANDLE,
+			UVERBS_OBJECT_COMP_CNTR,
+			UVERBS_ACCESS_DESTROY,
+			UA_MANDATORY));
+
+DECLARE_UVERBS_NAMED_METHOD(
+	UVERBS_METHOD_COMP_CNTR_SET,
+	UVERBS_ATTR_IDR(UVERBS_ATTR_SET_COMP_CNTR_HANDLE,
+			UVERBS_OBJECT_COMP_CNTR,
+			UVERBS_ACCESS_WRITE,
+			UA_MANDATORY),
+	UVERBS_ATTR_PTR_IN(UVERBS_ATTR_SET_COMP_CNTR_VALUE,
+			   UVERBS_ATTR_TYPE(u64),
+			   UA_MANDATORY));
+
+DECLARE_UVERBS_NAMED_METHOD(
+	UVERBS_METHOD_COMP_CNTR_SET_ERR,
+	UVERBS_ATTR_IDR(UVERBS_ATTR_SET_ERR_COMP_CNTR_HANDLE,
+			UVERBS_OBJECT_COMP_CNTR,
+			UVERBS_ACCESS_WRITE,
+			UA_MANDATORY),
+	UVERBS_ATTR_PTR_IN(UVERBS_ATTR_SET_ERR_COMP_CNTR_VALUE,
+			   UVERBS_ATTR_TYPE(u64),
+			   UA_MANDATORY));
+
+DECLARE_UVERBS_NAMED_METHOD(
+	UVERBS_METHOD_COMP_CNTR_INC,
+	UVERBS_ATTR_IDR(UVERBS_ATTR_INC_COMP_CNTR_HANDLE,
+			UVERBS_OBJECT_COMP_CNTR,
+			UVERBS_ACCESS_WRITE,
+			UA_MANDATORY),
+	UVERBS_ATTR_PTR_IN(UVERBS_ATTR_INC_COMP_CNTR_VALUE,
+			   UVERBS_ATTR_TYPE(u64),
+			   UA_MANDATORY));
+
+DECLARE_UVERBS_NAMED_METHOD(
+	UVERBS_METHOD_COMP_CNTR_INC_ERR,
+	UVERBS_ATTR_IDR(UVERBS_ATTR_INC_ERR_COMP_CNTR_HANDLE,
+			UVERBS_OBJECT_COMP_CNTR,
+			UVERBS_ACCESS_WRITE,
+			UA_MANDATORY),
+	UVERBS_ATTR_PTR_IN(UVERBS_ATTR_INC_ERR_COMP_CNTR_VALUE,
+			   UVERBS_ATTR_TYPE(u64),
+			   UA_MANDATORY));
+
+DECLARE_UVERBS_NAMED_METHOD(
+	UVERBS_METHOD_COMP_CNTR_READ,
+	UVERBS_ATTR_IDR(UVERBS_ATTR_READ_COMP_CNTR_HANDLE,
+			UVERBS_OBJECT_COMP_CNTR,
+			UVERBS_ACCESS_READ,
+			UA_MANDATORY),
+	UVERBS_ATTR_PTR_OUT(UVERBS_ATTR_READ_COMP_CNTR_RESP_VALUE,
+			    UVERBS_ATTR_TYPE(u64),
+			    UA_MANDATORY));
+
+DECLARE_UVERBS_NAMED_METHOD(
+	UVERBS_METHOD_COMP_CNTR_READ_ERR,
+	UVERBS_ATTR_IDR(UVERBS_ATTR_READ_ERR_COMP_CNTR_HANDLE,
+			UVERBS_OBJECT_COMP_CNTR,
+			UVERBS_ACCESS_READ,
+			UA_MANDATORY),
+	UVERBS_ATTR_PTR_OUT(UVERBS_ATTR_READ_ERR_COMP_CNTR_RESP_VALUE,
+			    UVERBS_ATTR_TYPE(u64),
+			    UA_MANDATORY));
+
+DECLARE_UVERBS_NAMED_OBJECT(
+	UVERBS_OBJECT_COMP_CNTR,
+	UVERBS_TYPE_ALLOC_IDR(uverbs_free_comp_cntr),
+	&UVERBS_METHOD(UVERBS_METHOD_COMP_CNTR_CREATE),
+	&UVERBS_METHOD(UVERBS_METHOD_COMP_CNTR_DESTROY),
+	&UVERBS_METHOD(UVERBS_METHOD_COMP_CNTR_SET),
+	&UVERBS_METHOD(UVERBS_METHOD_COMP_CNTR_SET_ERR),
+	&UVERBS_METHOD(UVERBS_METHOD_COMP_CNTR_INC),
+	&UVERBS_METHOD(UVERBS_METHOD_COMP_CNTR_INC_ERR),
+	&UVERBS_METHOD(UVERBS_METHOD_COMP_CNTR_READ),
+	&UVERBS_METHOD(UVERBS_METHOD_COMP_CNTR_READ_ERR));
+
+const struct uapi_definition uverbs_def_obj_comp_cntr[] = {
+	UAPI_DEF_CHAIN_OBJ_TREE_NAMED(UVERBS_OBJECT_COMP_CNTR,
+				      UAPI_DEF_OBJ_NEEDS_FN(destroy_comp_cntr)),
+	{}
+};
diff --git a/drivers/infiniband/core/uverbs_std_types_qp.c b/drivers/infiniband/core/uverbs_std_types_qp.c
index be0730e8509e..2c607b02d9d5 100644
--- a/drivers/infiniband/core/uverbs_std_types_qp.c
+++ b/drivers/infiniband/core/uverbs_std_types_qp.c
@@ -367,11 +367,54 @@ DECLARE_UVERBS_NAMED_METHOD(
 			    UVERBS_ATTR_TYPE(struct ib_uverbs_destroy_qp_resp),
 			    UA_MANDATORY));
 
+static int UVERBS_HANDLER(UVERBS_METHOD_QP_ATTACH_COMP_CNTR)(
+	struct uverbs_attr_bundle *attrs)
+{
+	struct ib_uobject *qp_uobj = uverbs_attr_get_uobject(
+		attrs, UVERBS_ATTR_QP_ATTACH_COMP_CNTR_QP_HANDLE);
+	struct ib_comp_cntr *cc = uverbs_attr_get_obj(
+		attrs, UVERBS_ATTR_QP_ATTACH_COMP_CNTR_HANDLE);
+	struct ib_comp_cntr_attach_attr attr = {};
+	struct ib_qp *qp = qp_uobj->object;
+	int ret;
+
+	if (!cc->device->ops.qp_attach_comp_cntr)
+		return -EOPNOTSUPP;
+
+	ret = uverbs_get_flags32(&attr.op_mask, attrs,
+				 UVERBS_ATTR_QP_ATTACH_COMP_CNTR_OP_MASK,
+				 IB_UVERBS_COMP_CNTR_ATTACH_OP_SEND |
+				 IB_UVERBS_COMP_CNTR_ATTACH_OP_RECV |
+				 IB_UVERBS_COMP_CNTR_ATTACH_OP_RDMA_READ |
+				 IB_UVERBS_COMP_CNTR_ATTACH_OP_REMOTE_RDMA_READ |
+				 IB_UVERBS_COMP_CNTR_ATTACH_OP_RDMA_WRITE |
+				 IB_UVERBS_COMP_CNTR_ATTACH_OP_REMOTE_RDMA_WRITE);
+	if (ret)
+		return ret;
+
+	return qp->device->ops.qp_attach_comp_cntr(qp, cc, &attr);
+}
+
+DECLARE_UVERBS_NAMED_METHOD(
+	UVERBS_METHOD_QP_ATTACH_COMP_CNTR,
+	UVERBS_ATTR_IDR(UVERBS_ATTR_QP_ATTACH_COMP_CNTR_QP_HANDLE,
+			UVERBS_OBJECT_QP,
+			UVERBS_ACCESS_WRITE,
+			UA_MANDATORY),
+	UVERBS_ATTR_IDR(UVERBS_ATTR_QP_ATTACH_COMP_CNTR_HANDLE,
+			UVERBS_OBJECT_COMP_CNTR,
+			UVERBS_ACCESS_READ,
+			UA_MANDATORY),
+	UVERBS_ATTR_FLAGS_IN(UVERBS_ATTR_QP_ATTACH_COMP_CNTR_OP_MASK,
+			     enum ib_uverbs_comp_cntr_attach_op,
+			     UA_OPTIONAL));
+
 DECLARE_UVERBS_NAMED_OBJECT(
 	UVERBS_OBJECT_QP,
 	UVERBS_TYPE_ALLOC_IDR_SZ(sizeof(struct ib_uqp_object), uverbs_free_qp),
 	&UVERBS_METHOD(UVERBS_METHOD_QP_CREATE),
-	&UVERBS_METHOD(UVERBS_METHOD_QP_DESTROY));
+	&UVERBS_METHOD(UVERBS_METHOD_QP_DESTROY),
+	&UVERBS_METHOD(UVERBS_METHOD_QP_ATTACH_COMP_CNTR));
 
 const struct uapi_definition uverbs_def_obj_qp[] = {
 	UAPI_DEF_CHAIN_OBJ_TREE_NAMED(UVERBS_OBJECT_QP,
diff --git a/drivers/infiniband/core/uverbs_uapi.c b/drivers/infiniband/core/uverbs_uapi.c
index 31b248295854..a3f42a50a14f 100644
--- a/drivers/infiniband/core/uverbs_uapi.c
+++ b/drivers/infiniband/core/uverbs_uapi.c
@@ -628,6 +628,7 @@ void uverbs_destroy_api(struct uverbs_api *uapi)
 static const struct uapi_definition uverbs_core_api[] = {
 	UAPI_DEF_CHAIN(uverbs_def_obj_async_fd),
 	UAPI_DEF_CHAIN(uverbs_def_obj_counters),
+	UAPI_DEF_CHAIN(uverbs_def_obj_comp_cntr),
 	UAPI_DEF_CHAIN(uverbs_def_obj_cq),
 	UAPI_DEF_CHAIN(uverbs_def_obj_device),
 	UAPI_DEF_CHAIN(uverbs_def_obj_dm),
diff --git a/include/rdma/ib_verbs.h b/include/rdma/ib_verbs.h
index 9dd76f489a0b..76fa705389a4 100644
--- a/include/rdma/ib_verbs.h
+++ b/include/rdma/ib_verbs.h
@@ -453,6 +453,7 @@ struct ib_device_attr {
 	u64			max_dm_size;
 	/* Max entries for sgl for optimized performance per READ */
 	u32			max_sgl_rd;
+	u32			max_comp_cntr;
 };
 
 enum ib_mtu {
@@ -1746,6 +1747,19 @@ struct ib_cq {
 	struct rdma_restrack_entry res;
 };
 
+struct ib_comp_cntr {
+	struct ib_device	*device;
+	struct ib_uobject	*uobject;
+	struct ib_umem		*comp_umem;
+	struct ib_umem		*err_umem;
+	u64			comp_count_max_value;
+	u64			err_count_max_value;
+};
+
+struct ib_comp_cntr_attach_attr {
+	u32 op_mask;
+};
+
 struct ib_srq {
 	struct ib_device       *device;
 	struct ib_pd	       *pd;
@@ -2624,6 +2638,8 @@ struct ib_device_ops {
 			 struct ib_udata *udata);
 	int (*modify_qp)(struct ib_qp *qp, struct ib_qp_attr *qp_attr,
 			 int qp_attr_mask, struct ib_udata *udata);
+	int (*qp_attach_comp_cntr)(struct ib_qp *qp, struct ib_comp_cntr *cc,
+				   struct ib_comp_cntr_attach_attr *attr);
 	int (*query_qp)(struct ib_qp *qp, struct ib_qp_attr *qp_attr,
 			int qp_attr_mask, struct ib_qp_init_attr *qp_init_attr);
 	int (*destroy_qp)(struct ib_qp *qp, struct ib_udata *udata);
@@ -2645,6 +2661,15 @@ struct ib_device_ops {
 	 * post_destroy_cq - Free all kernel resources
 	 */
 	void (*post_destroy_cq)(struct ib_cq *cq);
+	int (*create_comp_cntr)(struct ib_comp_cntr *cc,
+				struct uverbs_attr_bundle *attrs);
+	int (*destroy_comp_cntr)(struct ib_comp_cntr *cc);
+	int (*set_comp_cntr)(struct ib_comp_cntr *cc, u64 value);
+	int (*set_err_comp_cntr)(struct ib_comp_cntr *cc, u64 value);
+	int (*inc_comp_cntr)(struct ib_comp_cntr *cc, u64 amount);
+	int (*inc_err_comp_cntr)(struct ib_comp_cntr *cc, u64 amount);
+	int (*read_comp_cntr)(struct ib_comp_cntr *cc, u64 *value);
+	int (*read_err_comp_cntr)(struct ib_comp_cntr *cc, u64 *value);
 	struct ib_mr *(*get_dma_mr)(struct ib_pd *pd, int mr_access_flags);
 	struct ib_mr *(*reg_user_mr)(struct ib_pd *pd, u64 start, u64 length,
 				     u64 virt_addr, int mr_access_flags,
@@ -2878,6 +2903,7 @@ struct ib_device_ops {
 	DECLARE_RDMA_OBJ_SIZE(ib_ah);
 	DECLARE_RDMA_OBJ_SIZE(ib_counters);
 	DECLARE_RDMA_OBJ_SIZE(ib_cq);
+	DECLARE_RDMA_OBJ_SIZE(ib_comp_cntr);
 	DECLARE_RDMA_OBJ_SIZE(ib_dmah);
 	DECLARE_RDMA_OBJ_SIZE(ib_mw);
 	DECLARE_RDMA_OBJ_SIZE(ib_pd);
diff --git a/include/uapi/rdma/ib_user_ioctl_cmds.h b/include/uapi/rdma/ib_user_ioctl_cmds.h
index 72041c1b0ea5..f66ae6d44df4 100644
--- a/include/uapi/rdma/ib_user_ioctl_cmds.h
+++ b/include/uapi/rdma/ib_user_ioctl_cmds.h
@@ -57,6 +57,7 @@ enum uverbs_default_objects {
 	UVERBS_OBJECT_ASYNC_EVENT,
 	UVERBS_OBJECT_DMAH,
 	UVERBS_OBJECT_DMABUF,
+	UVERBS_OBJECT_COMP_CNTR,
 };
 
 enum {
@@ -168,6 +169,7 @@ enum uverbs_attrs_destroy_qp_cmd_attr_ids {
 enum uverbs_methods_qp {
 	UVERBS_METHOD_QP_CREATE,
 	UVERBS_METHOD_QP_DESTROY,
+	UVERBS_METHOD_QP_ATTACH_COMP_CNTR,
 };
 
 enum uverbs_attrs_create_srq_cmd_attr_ids {
@@ -434,4 +436,67 @@ enum uverbs_attrs_query_gid_entry_cmd_attr_ids {
 	UVERBS_ATTR_QUERY_GID_ENTRY_RESP_ENTRY,
 };
 
+enum uverbs_methods_comp_cntr {
+	UVERBS_METHOD_COMP_CNTR_CREATE,
+	UVERBS_METHOD_COMP_CNTR_DESTROY,
+	UVERBS_METHOD_COMP_CNTR_SET,
+	UVERBS_METHOD_COMP_CNTR_SET_ERR,
+	UVERBS_METHOD_COMP_CNTR_INC,
+	UVERBS_METHOD_COMP_CNTR_INC_ERR,
+	UVERBS_METHOD_COMP_CNTR_READ,
+	UVERBS_METHOD_COMP_CNTR_READ_ERR,
+};
+
+enum uverbs_attrs_create_comp_cntr_cmd_attr_ids {
+	UVERBS_ATTR_CREATE_COMP_CNTR_HANDLE,
+	UVERBS_ATTR_CREATE_COMP_CNTR_BUFFER_VA,
+	UVERBS_ATTR_CREATE_COMP_CNTR_BUFFER_FD,
+	UVERBS_ATTR_CREATE_COMP_CNTR_BUFFER_OFFSET,
+	UVERBS_ATTR_CREATE_COMP_CNTR_ERR_BUFFER_VA,
+	UVERBS_ATTR_CREATE_COMP_CNTR_ERR_BUFFER_FD,
+	UVERBS_ATTR_CREATE_COMP_CNTR_ERR_BUFFER_OFFSET,
+	UVERBS_ATTR_CREATE_COMP_CNTR_RESP_COUNT_MAX_VALUE,
+	UVERBS_ATTR_CREATE_COMP_CNTR_RESP_ERR_COUNT_MAX_VALUE,
+};
+
+enum uverbs_attrs_destroy_comp_cntr_cmd_attr_ids {
+	UVERBS_ATTR_DESTROY_COMP_CNTR_HANDLE,
+};
+
+enum uverbs_attrs_set_comp_cntr_cmd_attr_ids {
+	UVERBS_ATTR_SET_COMP_CNTR_HANDLE,
+	UVERBS_ATTR_SET_COMP_CNTR_VALUE,
+};
+
+enum uverbs_attrs_set_err_comp_cntr_cmd_attr_ids {
+	UVERBS_ATTR_SET_ERR_COMP_CNTR_HANDLE,
+	UVERBS_ATTR_SET_ERR_COMP_CNTR_VALUE,
+};
+
+enum uverbs_attrs_inc_comp_cntr_cmd_attr_ids {
+	UVERBS_ATTR_INC_COMP_CNTR_HANDLE,
+	UVERBS_ATTR_INC_COMP_CNTR_VALUE,
+};
+
+enum uverbs_attrs_inc_err_comp_cntr_cmd_attr_ids {
+	UVERBS_ATTR_INC_ERR_COMP_CNTR_HANDLE,
+	UVERBS_ATTR_INC_ERR_COMP_CNTR_VALUE,
+};
+
+enum uverbs_attrs_read_comp_cntr_cmd_attr_ids {
+	UVERBS_ATTR_READ_COMP_CNTR_HANDLE,
+	UVERBS_ATTR_READ_COMP_CNTR_RESP_VALUE,
+};
+
+enum uverbs_attrs_read_err_comp_cntr_cmd_attr_ids {
+	UVERBS_ATTR_READ_ERR_COMP_CNTR_HANDLE,
+	UVERBS_ATTR_READ_ERR_COMP_CNTR_RESP_VALUE,
+};
+
+enum uverbs_attrs_qp_attach_comp_cntr_cmd_attr_ids {
+	UVERBS_ATTR_QP_ATTACH_COMP_CNTR_QP_HANDLE,
+	UVERBS_ATTR_QP_ATTACH_COMP_CNTR_HANDLE,
+	UVERBS_ATTR_QP_ATTACH_COMP_CNTR_OP_MASK,
+};
+
 #endif
diff --git a/include/uapi/rdma/ib_user_ioctl_verbs.h b/include/uapi/rdma/ib_user_ioctl_verbs.h
index 90c5cd8e7753..45e6f1fccf80 100644
--- a/include/uapi/rdma/ib_user_ioctl_verbs.h
+++ b/include/uapi/rdma/ib_user_ioctl_verbs.h
@@ -273,4 +273,13 @@ struct ib_uverbs_gid_entry {
 	__u32 netdev_ifindex; /* It is 0 if there is no netdev associated with it */
 };
 
+enum ib_uverbs_comp_cntr_attach_op {
+	IB_UVERBS_COMP_CNTR_ATTACH_OP_SEND = 1 << 0,
+	IB_UVERBS_COMP_CNTR_ATTACH_OP_RECV = 1 << 1,
+	IB_UVERBS_COMP_CNTR_ATTACH_OP_RDMA_READ = 1 << 2,
+	IB_UVERBS_COMP_CNTR_ATTACH_OP_REMOTE_RDMA_READ = 1 << 3,
+	IB_UVERBS_COMP_CNTR_ATTACH_OP_RDMA_WRITE = 1 << 4,
+	IB_UVERBS_COMP_CNTR_ATTACH_OP_REMOTE_RDMA_WRITE = 1 << 5,
+};
+
 #endif
diff --git a/include/uapi/rdma/ib_user_verbs.h b/include/uapi/rdma/ib_user_verbs.h
index 3b7bd99813e9..45d142f4a7f8 100644
--- a/include/uapi/rdma/ib_user_verbs.h
+++ b/include/uapi/rdma/ib_user_verbs.h
@@ -299,7 +299,7 @@ struct ib_uverbs_ex_query_device_resp {
 	struct ib_uverbs_cq_moderation_caps cq_moderation_caps;
 	__aligned_u64 max_dm_size;
 	__u32 xrc_odp_caps;
-	__u32 reserved;
+	__u32 max_comp_cntr;
 };
 
 struct ib_uverbs_query_port {
-- 
2.47.3


^ permalink raw reply related	[flat|nested] 14+ messages in thread

* [PATCH for-next 2/4] RDMA/core: Add Completion Counters to resource tracking
  2026-04-07 11:54 [PATCH for-next 0/4] Introduce Completion Counters Michael Margolin
  2026-04-07 11:54 ` [PATCH for-next 1/4] RDMA/core: Add Completion Counters support Michael Margolin
@ 2026-04-07 11:54 ` Michael Margolin
  2026-04-07 11:54 ` [PATCH for-next 3/4] RDMA/efa: Update device interface Michael Margolin
  2026-04-07 11:54 ` [PATCH for-next 4/4] RDMA/efa: Add Completion Counters support Michael Margolin
  3 siblings, 0 replies; 14+ messages in thread
From: Michael Margolin @ 2026-04-07 11:54 UTC (permalink / raw)
  To: jgg, leon, linux-rdma; +Cc: sleybo, matua, gal.pressman, Yonatan Nachum

Track completion counter objects in the resource tracking database so
they are visible through the rdma netlink interface. The rdma tool
displays the comp_cntr count in the resource summary.

Add RDMA_RESTRACK_COMP_CNTR type, embed rdma_restrack_entry in
ib_comp_cntr, and add the res_to_dev mapping. Register the resource
on create and remove it on destroy.

Reviewed-by: Yonatan Nachum <ynachum@amazon.com>
Signed-off-by: Michael Margolin <mrgolin@amazon.com>
---
 drivers/infiniband/core/nldev.c                      | 1 +
 drivers/infiniband/core/restrack.c                   | 2 ++
 drivers/infiniband/core/uverbs_std_types_comp_cntr.c | 6 ++++++
 include/rdma/ib_verbs.h                              | 1 +
 include/rdma/restrack.h                              | 4 ++++
 5 files changed, 14 insertions(+)

diff --git a/drivers/infiniband/core/nldev.c b/drivers/infiniband/core/nldev.c
index 96c745d5bac4..155954fef3e2 100644
--- a/drivers/infiniband/core/nldev.c
+++ b/drivers/infiniband/core/nldev.c
@@ -446,6 +446,7 @@ static int fill_res_info(struct sk_buff *msg, struct ib_device *device,
 		[RDMA_RESTRACK_MR] = "mr",
 		[RDMA_RESTRACK_CTX] = "ctx",
 		[RDMA_RESTRACK_SRQ] = "srq",
+		[RDMA_RESTRACK_COMP_CNTR] = "comp_cntr",
 	};
 
 	struct nlattr *table_attr;
diff --git a/drivers/infiniband/core/restrack.c b/drivers/infiniband/core/restrack.c
index ac3688952cab..d152cc5f042b 100644
--- a/drivers/infiniband/core/restrack.c
+++ b/drivers/infiniband/core/restrack.c
@@ -102,6 +102,8 @@ static struct ib_device *res_to_dev(struct rdma_restrack_entry *res)
 		return container_of(res, struct ib_srq, res)->device;
 	case RDMA_RESTRACK_DMAH:
 		return container_of(res, struct ib_dmah, res)->device;
+	case RDMA_RESTRACK_COMP_CNTR:
+		return container_of(res, struct ib_comp_cntr, res)->device;
 	default:
 		WARN_ONCE(true, "Wrong resource tracking type %u\n", res->type);
 		return NULL;
diff --git a/drivers/infiniband/core/uverbs_std_types_comp_cntr.c b/drivers/infiniband/core/uverbs_std_types_comp_cntr.c
index a62c20d4e5a4..708cac838d43 100644
--- a/drivers/infiniband/core/uverbs_std_types_comp_cntr.c
+++ b/drivers/infiniband/core/uverbs_std_types_comp_cntr.c
@@ -8,6 +8,7 @@
 #include <rdma/ib_umem_dmabuf.h>
 #include "rdma_core.h"
 #include "uverbs.h"
+#include "restrack.h"
 
 static int uverbs_free_comp_cntr(struct ib_uobject *uobject,
 				 enum rdma_remove_reason why,
@@ -20,6 +21,7 @@ static int uverbs_free_comp_cntr(struct ib_uobject *uobject,
 	if (ret)
 		return ret;
 
+	rdma_restrack_del(&cc->res);
 	ib_umem_release(cc->comp_umem);
 	ib_umem_release(cc->err_umem);
 	kfree(cc);
@@ -120,7 +122,11 @@ static int UVERBS_HANDLER(UVERBS_METHOD_COMP_CNTR_CREATE)(
 	if (ret)
 		goto err_err_umem;
 
+	rdma_restrack_new(&cc->res, RDMA_RESTRACK_COMP_CNTR);
+	rdma_restrack_set_name(&cc->res, NULL);
+
 	uobj->object = cc;
+	rdma_restrack_add(&cc->res);
 	uverbs_finalize_uobj_create(attrs, UVERBS_ATTR_CREATE_COMP_CNTR_HANDLE);
 
 	ret = uverbs_copy_to(attrs,
diff --git a/include/rdma/ib_verbs.h b/include/rdma/ib_verbs.h
index 76fa705389a4..2193e9d678cb 100644
--- a/include/rdma/ib_verbs.h
+++ b/include/rdma/ib_verbs.h
@@ -1754,6 +1754,7 @@ struct ib_comp_cntr {
 	struct ib_umem		*err_umem;
 	u64			comp_count_max_value;
 	u64			err_count_max_value;
+	struct rdma_restrack_entry res;
 };
 
 struct ib_comp_cntr_attach_attr {
diff --git a/include/rdma/restrack.h b/include/rdma/restrack.h
index 451f99e3717d..4ab72bc6d8c7 100644
--- a/include/rdma/restrack.h
+++ b/include/rdma/restrack.h
@@ -60,6 +60,10 @@ enum rdma_restrack_type {
 	 * @RDMA_RESTRACK_DMAH: DMA handle
 	 */
 	RDMA_RESTRACK_DMAH,
+	/**
+	 * @RDMA_RESTRACK_COMP_CNTR: Completion Counter
+	 */
+	RDMA_RESTRACK_COMP_CNTR,
 	/**
 	 * @RDMA_RESTRACK_MAX: Last entry, used for array dclarations
 	 */
-- 
2.47.3


^ permalink raw reply related	[flat|nested] 14+ messages in thread

* [PATCH for-next 3/4] RDMA/efa: Update device interface
  2026-04-07 11:54 [PATCH for-next 0/4] Introduce Completion Counters Michael Margolin
  2026-04-07 11:54 ` [PATCH for-next 1/4] RDMA/core: Add Completion Counters support Michael Margolin
  2026-04-07 11:54 ` [PATCH for-next 2/4] RDMA/core: Add Completion Counters to resource tracking Michael Margolin
@ 2026-04-07 11:54 ` Michael Margolin
  2026-04-07 11:54 ` [PATCH for-next 4/4] RDMA/efa: Add Completion Counters support Michael Margolin
  3 siblings, 0 replies; 14+ messages in thread
From: Michael Margolin @ 2026-04-07 11:54 UTC (permalink / raw)
  To: jgg, leon, linux-rdma
  Cc: sleybo, matua, gal.pressman, Daniel Kinsbursky, Yonatan Nachum

Align device interface definitions.

Reviewed-by: Daniel Kinsbursky <dkinsb@amazon.com>
Reviewed-by: Yonatan Nachum <ynachum@amazon.com>
Signed-off-by: Michael Margolin <mrgolin@amazon.com>
---
 .../infiniband/hw/efa/efa_admin_cmds_defs.h   | 185 +++++++++++++++++-
 drivers/infiniband/hw/efa/efa_io_defs.h       |  62 +++++-
 2 files changed, 242 insertions(+), 5 deletions(-)

diff --git a/drivers/infiniband/hw/efa/efa_admin_cmds_defs.h b/drivers/infiniband/hw/efa/efa_admin_cmds_defs.h
index ad34ea5da6b0..2d75edabeefa 100644
--- a/drivers/infiniband/hw/efa/efa_admin_cmds_defs.h
+++ b/drivers/infiniband/hw/efa/efa_admin_cmds_defs.h
@@ -31,7 +31,12 @@ enum efa_admin_aq_opcode {
 	EFA_ADMIN_CREATE_EQ                         = 18,
 	EFA_ADMIN_DESTROY_EQ                        = 19,
 	EFA_ADMIN_ALLOC_MR                          = 20,
-	EFA_ADMIN_MAX_OPCODE                        = 20,
+	EFA_ADMIN_SERVICE                           = 21,
+	EFA_ADMIN_CREATE_COUNTER                    = 25,
+	EFA_ADMIN_DESTROY_COUNTER                   = 26,
+	EFA_ADMIN_ATTACH_COUNTER                    = 27,
+	EFA_ADMIN_MODIFY_COUNTER                    = 28,
+	EFA_ADMIN_MAX_OPCODE                        = 28,
 };
 
 enum efa_admin_aq_feature_id {
@@ -725,7 +730,9 @@ struct efa_admin_feature_device_attr_desc {
 	 *    on TX queues
 	 * 4 : unsolicited_write_recv - If set, unsolicited
 	 *    write with imm. receive is supported
-	 * 31:5 : reserved - MBZ
+	 * 5 : event_counters - If set, event counters are
+	 *    supported
+	 * 31:6 : reserved - MBZ
 	 */
 	u32 device_caps;
 
@@ -814,6 +821,34 @@ struct efa_admin_feature_queue_attr_desc_1 {
 struct efa_admin_feature_queue_attr_desc_2 {
 	/* Maximum size of data that can be sent inline in a Send WQE */
 	u16 inline_buf_size_ex;
+
+	/* MBZ */
+	u8 reserved[6];
+
+	/*
+	 * Supported counter QP events
+	 * 0 : send_comp
+	 * 1 : send_comp_err
+	 * 2 : recv_comp
+	 * 3 : recv_comp_err
+	 * 4 : read_comp
+	 * 5 : read_comp_err
+	 * 6 : write_comp
+	 * 7 : write_comp_err
+	 * 8 : remote_read_comp
+	 * 9 : remote_write_comp
+	 * 31:10 : reserved - MBZ
+	 */
+	u32 supported_counter_qp_events;
+
+	/* Maximum number of counters */
+	u32 max_event_counters;
+
+	/*
+	 * Maximum counter value, counter wraps around to 0 after reaching
+	 * this value
+	 */
+	u64 event_counter_max_val;
 };
 
 struct efa_admin_event_queue_attr_desc {
@@ -1092,6 +1127,127 @@ struct efa_admin_host_info {
 	u32 flags;
 };
 
+struct efa_admin_service_cmd {
+	struct efa_admin_aq_common_desc aq_common_descriptor;
+
+	u8 buffer[60];
+};
+
+struct efa_admin_service_resp {
+	struct efa_admin_acq_common_desc acq_common_desc;
+
+	u8 buffer[56];
+};
+
+/* Create Counter command */
+struct efa_admin_create_counter_cmd {
+	struct efa_admin_aq_common_desc aq_common_descriptor;
+
+	/* UAR number */
+	u16 uar;
+
+	/* MBZ */
+	u16 reserved;
+
+	/* Counter physical address */
+	u64 paddr;
+};
+
+struct efa_admin_create_counter_resp {
+	struct efa_admin_acq_common_desc acq_common_desc;
+
+	/* Counter handle */
+	u32 cntr_handle;
+
+	/* MBZ */
+	u32 reserved;
+};
+
+struct efa_admin_destroy_counter_cmd {
+	struct efa_admin_aq_common_desc aq_common_descriptor;
+
+	/* Counter handle */
+	u32 cntr_handle;
+};
+
+struct efa_admin_destroy_counter_resp {
+	struct efa_admin_acq_common_desc acq_common_desc;
+};
+
+enum efa_admin_counter_attach_type {
+	EFA_ADMIN_COUNTER_ATTACH_QP_EVENTS          = 0,
+};
+
+struct efa_admin_counter_attach_qp_events {
+	/* QP handle */
+	u32 qp_handle;
+
+	/*
+	 * Bitmask of counter QP events
+	 * 0 : send_comp
+	 * 1 : send_comp_err
+	 * 2 : recv_comp
+	 * 3 : recv_comp_err
+	 * 4 : read_comp
+	 * 5 : read_comp_err
+	 * 6 : write_comp
+	 * 7 : write_comp_err
+	 * 8 : remote_read_comp
+	 * 9 : remote_write_comp
+	 * 31:10 : reserved - MBZ
+	 */
+	u32 events;
+};
+
+struct efa_admin_attach_counter_cmd {
+	struct efa_admin_aq_common_desc aq_common_descriptor;
+
+	/* Counter handle */
+	u32 cntr_handle;
+
+	/* efa_admin_counter_attach_type */
+	u8 attach_type;
+
+	/* MBZ */
+	u8 reserved[3];
+
+	union {
+		struct efa_admin_counter_attach_qp_events qp_events;
+	} u;
+};
+
+struct efa_admin_attach_counter_resp {
+	struct efa_admin_acq_common_desc acq_common_desc;
+};
+
+/* Counter modify operations */
+enum efa_admin_counter_modify_ops {
+	/* Set counter value */
+	EFA_ADMIN_COUNTER_MODIFY_SET                = 0,
+	/* Add to counter value */
+	EFA_ADMIN_COUNTER_MODIFY_ADD                = 1,
+};
+
+struct efa_admin_modify_counter_cmd {
+	struct efa_admin_aq_common_desc aq_common_descriptor;
+
+	/* Counter handle */
+	u32 cntr_handle;
+
+	/* Counter operation type (efa_admin_counter_modify_ops) */
+	u8 operation;
+
+	/* MBZ */
+	u8 reserved[7];
+
+	/* Value for SET or ADD */
+	u64 value;
+};
+
+struct efa_admin_modify_counter_resp {
+	struct efa_admin_acq_common_desc acq_common_desc;
+};
+
 /* create_qp_cmd */
 #define EFA_ADMIN_CREATE_QP_CMD_SQ_VIRT_MASK                BIT(0)
 #define EFA_ADMIN_CREATE_QP_CMD_RQ_VIRT_MASK                BIT(1)
@@ -1132,6 +1288,19 @@ struct efa_admin_host_info {
 #define EFA_ADMIN_FEATURE_DEVICE_ATTR_DESC_DATA_POLLING_128_MASK BIT(2)
 #define EFA_ADMIN_FEATURE_DEVICE_ATTR_DESC_RDMA_WRITE_MASK  BIT(3)
 #define EFA_ADMIN_FEATURE_DEVICE_ATTR_DESC_UNSOLICITED_WRITE_RECV_MASK BIT(4)
+#define EFA_ADMIN_FEATURE_DEVICE_ATTR_DESC_EVENT_COUNTERS_MASK BIT(5)
+
+/* feature_queue_attr_desc_2 */
+#define EFA_ADMIN_FEATURE_QUEUE_ATTR_DESC_2_SEND_COMP_MASK  BIT(0)
+#define EFA_ADMIN_FEATURE_QUEUE_ATTR_DESC_2_SEND_COMP_ERR_MASK BIT(1)
+#define EFA_ADMIN_FEATURE_QUEUE_ATTR_DESC_2_RECV_COMP_MASK  BIT(2)
+#define EFA_ADMIN_FEATURE_QUEUE_ATTR_DESC_2_RECV_COMP_ERR_MASK BIT(3)
+#define EFA_ADMIN_FEATURE_QUEUE_ATTR_DESC_2_READ_COMP_MASK  BIT(4)
+#define EFA_ADMIN_FEATURE_QUEUE_ATTR_DESC_2_READ_COMP_ERR_MASK BIT(5)
+#define EFA_ADMIN_FEATURE_QUEUE_ATTR_DESC_2_WRITE_COMP_MASK BIT(6)
+#define EFA_ADMIN_FEATURE_QUEUE_ATTR_DESC_2_WRITE_COMP_ERR_MASK BIT(7)
+#define EFA_ADMIN_FEATURE_QUEUE_ATTR_DESC_2_REMOTE_READ_COMP_MASK BIT(8)
+#define EFA_ADMIN_FEATURE_QUEUE_ATTR_DESC_2_REMOTE_WRITE_COMP_MASK BIT(9)
 
 /* create_eq_cmd */
 #define EFA_ADMIN_CREATE_EQ_CMD_ENTRY_SIZE_WORDS_MASK       GENMASK(4, 0)
@@ -1150,4 +1319,16 @@ struct efa_admin_host_info {
 #define EFA_ADMIN_HOST_INFO_INTREE_MASK                     BIT(0)
 #define EFA_ADMIN_HOST_INFO_GDR_MASK                        BIT(1)
 
+/* counter_attach_qp_events */
+#define EFA_ADMIN_COUNTER_ATTACH_QP_EVENTS_SEND_COMP_MASK   BIT(0)
+#define EFA_ADMIN_COUNTER_ATTACH_QP_EVENTS_SEND_COMP_ERR_MASK BIT(1)
+#define EFA_ADMIN_COUNTER_ATTACH_QP_EVENTS_RECV_COMP_MASK   BIT(2)
+#define EFA_ADMIN_COUNTER_ATTACH_QP_EVENTS_RECV_COMP_ERR_MASK BIT(3)
+#define EFA_ADMIN_COUNTER_ATTACH_QP_EVENTS_READ_COMP_MASK   BIT(4)
+#define EFA_ADMIN_COUNTER_ATTACH_QP_EVENTS_READ_COMP_ERR_MASK BIT(5)
+#define EFA_ADMIN_COUNTER_ATTACH_QP_EVENTS_WRITE_COMP_MASK  BIT(6)
+#define EFA_ADMIN_COUNTER_ATTACH_QP_EVENTS_WRITE_COMP_ERR_MASK BIT(7)
+#define EFA_ADMIN_COUNTER_ATTACH_QP_EVENTS_REMOTE_READ_COMP_MASK BIT(8)
+#define EFA_ADMIN_COUNTER_ATTACH_QP_EVENTS_REMOTE_WRITE_COMP_MASK BIT(9)
+
 #endif /* _EFA_ADMIN_CMDS_H_ */
diff --git a/drivers/infiniband/hw/efa/efa_io_defs.h b/drivers/infiniband/hw/efa/efa_io_defs.h
index a4c9fd33da38..874698e19647 100644
--- a/drivers/infiniband/hw/efa/efa_io_defs.h
+++ b/drivers/infiniband/hw/efa/efa_io_defs.h
@@ -9,6 +9,7 @@
 #define EFA_IO_TX_DESC_NUM_BUFS              2
 #define EFA_IO_TX_DESC_NUM_RDMA_BUFS         1
 #define EFA_IO_TX_DESC_INLINE_MAX_SIZE       32
+#define EFA_IO_TX_DESC_INLINE_MAX_SIZE_128   80
 #define EFA_IO_TX_DESC_IMM_DATA_SIZE         4
 #define EFA_IO_TX_DESC_INLINE_PBL_SIZE       1
 
@@ -65,6 +66,8 @@ enum efa_io_comp_status {
 	EFA_IO_COMP_STATUS_REMOTE_ERROR_UNKNOWN_PEER = 14,
 	/* Unreachable remote - never received a response */
 	EFA_IO_COMP_STATUS_LOCAL_ERROR_UNREACH_REMOTE = 15,
+	/* Remote feature mismatch */
+	EFA_IO_COMP_STATUS_REMOTE_ERROR_FEATURE_MISMATCH = 18,
 };
 
 enum efa_io_frwr_pbl_mode {
@@ -72,6 +75,13 @@ enum efa_io_frwr_pbl_mode {
 	EFA_IO_FRWR_DIRECT_PBL                      = 1,
 };
 
+enum efa_io_processing_hint {
+	/* Default value */
+	EFA_IO_PROCESSING_HINT_NONE                 = 0,
+	/* Optimize for throughput */
+	EFA_IO_PROCESSING_HINT_BURST_PPS_SENSITIVE  = 1,
+};
+
 struct efa_io_tx_meta_desc {
 	/* Verbs-generated Request ID */
 	u16 req_id;
@@ -121,7 +131,14 @@ struct efa_io_tx_meta_desc {
 
 	u16 ah;
 
-	u16 reserved;
+	/*
+	 * control flags
+	 * 1:0 : processing_hint - enum efa_io_processing_hint
+	 * 7:2 : reserved - MBZ
+	 */
+	u8 ctrl3;
+
+	u8 reserved;
 
 	/* Queue key */
 	u32 qkey;
@@ -172,6 +189,19 @@ struct efa_io_rdma_req {
 	struct efa_io_tx_buf_desc local_mem[1];
 };
 
+struct efa_io_rdma_req_128 {
+	/* Remote memory address */
+	struct efa_io_remote_mem_addr remote_mem;
+
+	union {
+		/* Local memory address */
+		struct efa_io_tx_buf_desc local_mem[1];
+
+		/* inline data for RDMA */
+		u8 inline_data[80];
+	};
+};
+
 struct efa_io_fast_mr_reg_req {
 	/* Updated local key of the MR after lkey/rkey increment */
 	u32 lkey;
@@ -230,8 +260,8 @@ struct efa_io_fast_mr_inv_req {
 };
 
 /*
- * Tx WQE, composed of tx meta descriptors followed by either tx buffer
- * descriptors or inline data
+ * 64-byte Tx WQE, composed of tx meta descriptors followed by either tx
+ * buffer descriptors or inline data
  */
 struct efa_io_tx_wqe {
 	/* TX meta */
@@ -254,6 +284,31 @@ struct efa_io_tx_wqe {
 	} data;
 };
 
+/*
+ * 128-byte Tx WQE, composed of tx meta descriptors followed by either tx
+ * buffer descriptors or inline data
+ */
+struct efa_io_tx_wqe_128 {
+	/* TX meta */
+	struct efa_io_tx_meta_desc meta;
+
+	union {
+		/* Send buffer descriptors */
+		struct efa_io_tx_buf_desc sgl[2];
+
+		u8 inline_data[80];
+
+		/* RDMA local and remote memory addresses */
+		struct efa_io_rdma_req_128 rdma_req;
+
+		/* Fast registration */
+		struct efa_io_fast_mr_reg_req reg_mr_req;
+
+		/* Fast invalidation */
+		struct efa_io_fast_mr_inv_req inv_mr_req;
+	} data;
+};
+
 /*
  * Rx buffer descriptor; RX WQE is composed of one or more RX buffer
  * descriptors.
@@ -365,6 +420,7 @@ struct efa_io_rx_cdesc_ex {
 #define EFA_IO_TX_META_DESC_FIRST_MASK                      BIT(2)
 #define EFA_IO_TX_META_DESC_LAST_MASK                       BIT(3)
 #define EFA_IO_TX_META_DESC_COMP_REQ_MASK                   BIT(4)
+#define EFA_IO_TX_META_DESC_PROCESSING_HINT_MASK            GENMASK(1, 0)
 
 /* tx_buf_desc */
 #define EFA_IO_TX_BUF_DESC_LKEY_MASK                        GENMASK(23, 0)
-- 
2.47.3


^ permalink raw reply related	[flat|nested] 14+ messages in thread

* [PATCH for-next 4/4] RDMA/efa: Add Completion Counters support
  2026-04-07 11:54 [PATCH for-next 0/4] Introduce Completion Counters Michael Margolin
                   ` (2 preceding siblings ...)
  2026-04-07 11:54 ` [PATCH for-next 3/4] RDMA/efa: Update device interface Michael Margolin
@ 2026-04-07 11:54 ` Michael Margolin
  3 siblings, 0 replies; 14+ messages in thread
From: Michael Margolin @ 2026-04-07 11:54 UTC (permalink / raw)
  To: jgg, leon, linux-rdma; +Cc: sleybo, matua, gal.pressman

Implement completion counters for the EFA device. Each completion
counter is backed by two EFA event counters, one for success
completions and one for error completions.

Set and inc operations are forwarded to the device via the modify
counter admin command. Read operations return EOPNOTSUPP as the
counter values are accessed directly from userspace through the
mapped memory.

Signed-off-by: Michael Margolin <mrgolin@amazon.com>
---
 drivers/infiniband/hw/efa/efa.h         |  15 ++
 drivers/infiniband/hw/efa/efa_com_cmd.c | 106 ++++++++++++++
 drivers/infiniband/hw/efa/efa_com_cmd.h |  36 +++++
 drivers/infiniband/hw/efa/efa_main.c    |   8 ++
 drivers/infiniband/hw/efa/efa_verbs.c   | 177 ++++++++++++++++++++++++
 include/uapi/rdma/efa-abi.h             |   1 +
 6 files changed, 343 insertions(+)

diff --git a/drivers/infiniband/hw/efa/efa.h b/drivers/infiniband/hw/efa/efa.h
index 00b19f2ba3da..d0c2c355f031 100644
--- a/drivers/infiniband/hw/efa/efa.h
+++ b/drivers/infiniband/hw/efa/efa.h
@@ -110,6 +110,12 @@ struct efa_cq {
 	struct ib_umem *umem;
 };
 
+struct efa_comp_cntr {
+	struct ib_comp_cntr ibcc;
+	u32 comp_handle;
+	u32 err_handle;
+};
+
 struct efa_qp {
 	struct ib_qp ibqp;
 	dma_addr_t rq_dma_addr;
@@ -163,6 +169,15 @@ int efa_create_qp(struct ib_qp *ibqp, struct ib_qp_init_attr *init_attr,
 int efa_destroy_cq(struct ib_cq *ibcq, struct ib_udata *udata);
 int efa_create_user_cq(struct ib_cq *ibcq, const struct ib_cq_init_attr *attr,
 		       struct uverbs_attr_bundle *attrs);
+int efa_create_comp_cntr(struct ib_comp_cntr *ibcc,
+			 struct uverbs_attr_bundle *attrs);
+int efa_destroy_comp_cntr(struct ib_comp_cntr *ibcc);
+int efa_set_comp_cntr(struct ib_comp_cntr *ibcc, u64 value);
+int efa_set_err_comp_cntr(struct ib_comp_cntr *ibcc, u64 value);
+int efa_inc_comp_cntr(struct ib_comp_cntr *ibcc, u64 amount);
+int efa_inc_err_comp_cntr(struct ib_comp_cntr *ibcc, u64 amount);
+int efa_qp_attach_comp_cntr(struct ib_qp *ibqp, struct ib_comp_cntr *ibcc,
+			    struct ib_comp_cntr_attach_attr *attr);
 struct ib_mr *efa_reg_mr(struct ib_pd *ibpd, u64 start, u64 length,
 			 u64 virt_addr, int access_flags,
 			 struct ib_dmah *dmah,
diff --git a/drivers/infiniband/hw/efa/efa_com_cmd.c b/drivers/infiniband/hw/efa/efa_com_cmd.c
index 63c7f07806a8..e91c405e57d2 100644
--- a/drivers/infiniband/hw/efa/efa_com_cmd.c
+++ b/drivers/infiniband/hw/efa/efa_com_cmd.c
@@ -516,6 +516,8 @@ int efa_com_get_device_attr(struct efa_com_dev *edev,
 		}
 
 		result->inline_buf_size_ex = resp.u.queue_attr_2.inline_buf_size_ex;
+		result->max_event_counters = resp.u.queue_attr_2.max_event_counters;
+		result->event_counter_max_val = resp.u.queue_attr_2.event_counter_max_val;
 	} else {
 		result->inline_buf_size_ex = result->inline_buf_size;
 	}
@@ -851,3 +853,107 @@ int efa_com_get_stats(struct efa_com_dev *edev,
 
 	return 0;
 }
+
+int efa_com_create_counter(struct efa_com_dev *edev,
+			   struct efa_com_create_counter_params *params,
+			   struct efa_com_create_counter_result *result)
+{
+	struct efa_admin_create_counter_cmd cmd = {};
+	struct efa_com_admin_queue *aq = &edev->aq;
+	struct efa_admin_create_counter_resp resp;
+	int err;
+
+	cmd.aq_common_descriptor.opcode = EFA_ADMIN_CREATE_COUNTER;
+	cmd.uar = params->uarn;
+	cmd.paddr = params->dma_addr;
+
+	err = efa_com_cmd_exec(aq, (struct efa_admin_aq_entry *)&cmd,
+			       sizeof(cmd),
+			       (struct efa_admin_acq_entry *)&resp,
+			       sizeof(resp));
+	if (err) {
+		ibdev_err_ratelimited(edev->efa_dev,
+				      "Failed to create counter [%d]\n", err);
+		return err;
+	}
+
+	result->cntr_handle = resp.cntr_handle;
+	return 0;
+}
+
+int efa_com_destroy_counter(struct efa_com_dev *edev,
+			    struct efa_com_destroy_counter_params *params)
+{
+	struct efa_admin_destroy_counter_cmd cmd = {};
+	struct efa_admin_destroy_counter_resp resp;
+	struct efa_com_admin_queue *aq = &edev->aq;
+	int err;
+
+	cmd.aq_common_descriptor.opcode = EFA_ADMIN_DESTROY_COUNTER;
+	cmd.cntr_handle = params->cntr_handle;
+
+	err = efa_com_cmd_exec(aq, (struct efa_admin_aq_entry *)&cmd,
+			       sizeof(cmd),
+			       (struct efa_admin_acq_entry *)&resp,
+			       sizeof(resp));
+	if (err) {
+		ibdev_err_ratelimited(edev->efa_dev,
+				      "Failed to destroy counter [%d]\n", err);
+		return err;
+	}
+
+	return 0;
+}
+
+int efa_com_attach_counter(struct efa_com_dev *edev,
+			   struct efa_com_attach_counter_params *params)
+{
+	struct efa_admin_attach_counter_cmd cmd = {};
+	struct efa_com_admin_queue *aq = &edev->aq;
+	struct efa_admin_attach_counter_resp resp;
+	int err;
+
+	cmd.aq_common_descriptor.opcode = EFA_ADMIN_ATTACH_COUNTER;
+	cmd.cntr_handle = params->cntr_handle;
+	cmd.attach_type = EFA_ADMIN_COUNTER_ATTACH_QP_EVENTS;
+	cmd.u.qp_events.qp_handle = params->qp_handle;
+	cmd.u.qp_events.events = params->events;
+
+	err = efa_com_cmd_exec(aq, (struct efa_admin_aq_entry *)&cmd,
+			       sizeof(cmd),
+			       (struct efa_admin_acq_entry *)&resp,
+			       sizeof(resp));
+	if (err) {
+		ibdev_err_ratelimited(edev->efa_dev,
+				      "Failed to attach counter [%d]\n", err);
+		return err;
+	}
+
+	return 0;
+}
+
+int efa_com_modify_counter(struct efa_com_dev *edev,
+			   struct efa_com_modify_counter_params *params)
+{
+	struct efa_admin_modify_counter_cmd cmd = {};
+	struct efa_com_admin_queue *aq = &edev->aq;
+	struct efa_admin_modify_counter_resp resp;
+	int err;
+
+	cmd.aq_common_descriptor.opcode = EFA_ADMIN_MODIFY_COUNTER;
+	cmd.cntr_handle = params->cntr_handle;
+	cmd.operation = params->operation;
+	cmd.value = params->value;
+
+	err = efa_com_cmd_exec(aq, (struct efa_admin_aq_entry *)&cmd,
+			       sizeof(cmd),
+			       (struct efa_admin_acq_entry *)&resp,
+			       sizeof(resp));
+	if (err) {
+		ibdev_err_ratelimited(edev->efa_dev,
+				      "Failed to modify counter [%d]\n", err);
+		return err;
+	}
+
+	return 0;
+}
diff --git a/drivers/infiniband/hw/efa/efa_com_cmd.h b/drivers/infiniband/hw/efa/efa_com_cmd.h
index ef15b3c38429..9bce27d585d5 100644
--- a/drivers/infiniband/hw/efa/efa_com_cmd.h
+++ b/drivers/infiniband/hw/efa/efa_com_cmd.h
@@ -145,6 +145,8 @@ struct efa_com_get_device_attr_result {
 	u16 min_sq_depth;
 	u16 max_link_speed_gbps;
 	u8 db_bar;
+	u32 max_event_counters;
+	u64 event_counter_max_val;
 };
 
 struct efa_com_get_hw_hints_result {
@@ -300,6 +302,31 @@ union efa_com_get_stats_result {
 	struct efa_com_network_stats network_stats;
 };
 
+struct efa_com_create_counter_params {
+	dma_addr_t dma_addr;
+	u16 uarn;
+};
+
+struct efa_com_create_counter_result {
+	u32 cntr_handle;
+};
+
+struct efa_com_destroy_counter_params {
+	u32 cntr_handle;
+};
+
+struct efa_com_attach_counter_params {
+	u32 cntr_handle;
+	u32 qp_handle;
+	u32 events;
+};
+
+struct efa_com_modify_counter_params {
+	u32 cntr_handle;
+	u8 operation;
+	u64 value;
+};
+
 int efa_com_create_qp(struct efa_com_dev *edev,
 		      struct efa_com_create_qp_params *params,
 		      struct efa_com_create_qp_result *res);
@@ -350,5 +377,14 @@ int efa_com_dealloc_uar(struct efa_com_dev *edev,
 int efa_com_get_stats(struct efa_com_dev *edev,
 		      struct efa_com_get_stats_params *params,
 		      union efa_com_get_stats_result *result);
+int efa_com_create_counter(struct efa_com_dev *edev,
+			   struct efa_com_create_counter_params *params,
+			   struct efa_com_create_counter_result *result);
+int efa_com_destroy_counter(struct efa_com_dev *edev,
+			    struct efa_com_destroy_counter_params *params);
+int efa_com_attach_counter(struct efa_com_dev *edev,
+			   struct efa_com_attach_counter_params *params);
+int efa_com_modify_counter(struct efa_com_dev *edev,
+			   struct efa_com_modify_counter_params *params);
 
 #endif /* _EFA_COM_CMD_H_ */
diff --git a/drivers/infiniband/hw/efa/efa_main.c b/drivers/infiniband/hw/efa/efa_main.c
index 03c237c8c81e..e125120fe4ad 100644
--- a/drivers/infiniband/hw/efa/efa_main.c
+++ b/drivers/infiniband/hw/efa/efa_main.c
@@ -372,20 +372,25 @@ static const struct ib_device_ops efa_dev_ops = {
 	.alloc_pd = efa_alloc_pd,
 	.alloc_ucontext = efa_alloc_ucontext,
 	.create_user_cq = efa_create_user_cq,
+	.create_comp_cntr = efa_create_comp_cntr,
 	.create_qp = efa_create_qp,
 	.create_user_ah = efa_create_ah,
 	.dealloc_pd = efa_dealloc_pd,
 	.dealloc_ucontext = efa_dealloc_ucontext,
 	.dereg_mr = efa_dereg_mr,
 	.destroy_ah = efa_destroy_ah,
+	.destroy_comp_cntr = efa_destroy_comp_cntr,
 	.destroy_cq = efa_destroy_cq,
 	.destroy_qp = efa_destroy_qp,
 	.get_hw_stats = efa_get_hw_stats,
 	.get_link_layer = efa_port_link_layer,
 	.get_port_immutable = efa_get_port_immutable,
+	.inc_comp_cntr = efa_inc_comp_cntr,
+	.inc_err_comp_cntr = efa_inc_err_comp_cntr,
 	.mmap = efa_mmap,
 	.mmap_free = efa_mmap_free,
 	.modify_qp = efa_modify_qp,
+	.qp_attach_comp_cntr = efa_qp_attach_comp_cntr,
 	.query_device = efa_query_device,
 	.query_gid = efa_query_gid,
 	.query_pkey = efa_query_pkey,
@@ -393,9 +398,12 @@ static const struct ib_device_ops efa_dev_ops = {
 	.query_qp = efa_query_qp,
 	.reg_user_mr = efa_reg_mr,
 	.reg_user_mr_dmabuf = efa_reg_user_mr_dmabuf,
+	.set_comp_cntr = efa_set_comp_cntr,
+	.set_err_comp_cntr = efa_set_err_comp_cntr,
 
 	INIT_RDMA_OBJ_SIZE(ib_ah, efa_ah, ibah),
 	INIT_RDMA_OBJ_SIZE(ib_cq, efa_cq, ibcq),
+	INIT_RDMA_OBJ_SIZE(ib_comp_cntr, efa_comp_cntr, ibcc),
 	INIT_RDMA_OBJ_SIZE(ib_pd, efa_pd, ibpd),
 	INIT_RDMA_OBJ_SIZE(ib_qp, efa_qp, ibqp),
 	INIT_RDMA_OBJ_SIZE(ib_ucontext, efa_ucontext, ibucontext),
diff --git a/drivers/infiniband/hw/efa/efa_verbs.c b/drivers/infiniband/hw/efa/efa_verbs.c
index 283c62d9cb3d..e9dbb08f3e02 100644
--- a/drivers/infiniband/hw/efa/efa_verbs.c
+++ b/drivers/infiniband/hw/efa/efa_verbs.c
@@ -169,6 +169,11 @@ static inline struct efa_ah *to_eah(struct ib_ah *ibah)
 	return container_of(ibah, struct efa_ah, ibah);
 }
 
+static inline struct efa_comp_cntr *to_ecc(struct ib_comp_cntr *ibcc)
+{
+	return container_of(ibcc, struct efa_comp_cntr, ibcc);
+}
+
 static inline struct efa_user_mmap_entry *
 to_emmap(struct rdma_user_mmap_entry *rdma_entry)
 {
@@ -245,6 +250,7 @@ int efa_query_device(struct ib_device *ibdev,
 	props->max_recv_sge = dev_attr->max_rq_sge;
 	props->max_sge_rd = dev_attr->max_wr_rdma_sge;
 	props->max_pkeys = 1;
+	props->max_comp_cntr = dev_attr->max_event_counters / 2;
 
 	if (udata && udata->outlen) {
 		resp.max_sq_sge = dev_attr->max_sq_sge;
@@ -270,6 +276,9 @@ int efa_query_device(struct ib_device *ibdev,
 		if (EFA_DEV_CAP(dev, UNSOLICITED_WRITE_RECV))
 			resp.device_caps |= EFA_QUERY_DEVICE_CAPS_UNSOLICITED_WRITE_RECV;
 
+		if (EFA_DEV_CAP(dev, EVENT_COUNTERS))
+			resp.device_caps |= EFA_QUERY_DEVICE_CAPS_COMP_CNTR;
+
 		if (dev->neqs)
 			resp.device_caps |= EFA_QUERY_DEVICE_CAPS_CQ_NOTIFICATIONS;
 
@@ -2307,6 +2316,174 @@ enum rdma_link_layer efa_port_link_layer(struct ib_device *ibdev,
 	return IB_LINK_LAYER_UNSPECIFIED;
 }
 
+static int efa_create_event_counter(struct efa_dev *dev, struct ib_umem *umem,
+				    u16 uarn, u32 *handle)
+{
+	struct efa_com_create_counter_params params = {};
+	struct efa_com_create_counter_result result;
+	int err;
+
+	params.uarn = uarn;
+	params.dma_addr = ib_umem_start_dma_addr(umem);
+
+	err = efa_com_create_counter(&dev->edev, &params, &result);
+	if (err)
+		return err;
+
+	*handle = result.cntr_handle;
+	return 0;
+}
+
+static int efa_destroy_event_counter(struct efa_dev *dev, u32 handle)
+{
+	struct efa_com_destroy_counter_params params = {
+		.cntr_handle = handle,
+	};
+
+	return efa_com_destroy_counter(&dev->edev, &params);
+}
+
+int efa_create_comp_cntr(struct ib_comp_cntr *ibcc, struct uverbs_attr_bundle *attrs)
+{
+	struct efa_dev *dev = to_edev(ibcc->device);
+	struct efa_comp_cntr *cc = to_ecc(ibcc);
+	struct efa_ucontext *ucontext;
+	int err;
+
+	if (!ibcc->comp_umem || !ibcc->err_umem) {
+		ibdev_dbg(&dev->ibdev, "Completion Counter without umem isn't supported\n");
+		return -EOPNOTSUPP;
+	}
+
+	ucontext = rdma_udata_to_drv_context(&attrs->driver_udata, struct efa_ucontext,
+					     ibucontext);
+
+	err = efa_create_event_counter(dev, ibcc->comp_umem, ucontext->uarn, &cc->comp_handle);
+	if (err) {
+		ibdev_dbg(&dev->ibdev, "Failed to create comp event counter [%d]\n", err);
+		return err;
+	}
+
+	err = efa_create_event_counter(dev, ibcc->err_umem, ucontext->uarn, &cc->err_handle);
+	if (err) {
+		ibdev_dbg(&dev->ibdev, "Failed to create err event counter [%d]\n", err);
+		efa_destroy_event_counter(dev, cc->comp_handle);
+		return err;
+	}
+
+	ibcc->comp_count_max_value = dev->dev_attr.event_counter_max_val;
+	ibcc->err_count_max_value = dev->dev_attr.event_counter_max_val;
+
+	return 0;
+}
+
+int efa_destroy_comp_cntr(struct ib_comp_cntr *ibcc)
+{
+	struct efa_dev *dev = to_edev(ibcc->device);
+	struct efa_comp_cntr *cc = to_ecc(ibcc);
+	int err;
+
+	err = efa_destroy_event_counter(dev, cc->comp_handle);
+	if (err)
+		return err;
+
+	return efa_destroy_event_counter(dev, cc->err_handle);
+}
+
+static int efa_modify_event_counter(struct efa_dev *dev, u32 handle, u8 operation, u64 value)
+{
+	struct efa_com_modify_counter_params params = {
+		.cntr_handle = handle,
+		.operation = operation,
+		.value = value,
+	};
+
+	return efa_com_modify_counter(&dev->edev, &params);
+}
+
+int efa_set_comp_cntr(struct ib_comp_cntr *ibcc, u64 value)
+{
+	return efa_modify_event_counter(to_edev(ibcc->device), to_ecc(ibcc)->comp_handle,
+					EFA_ADMIN_COUNTER_MODIFY_SET, value);
+}
+
+int efa_set_err_comp_cntr(struct ib_comp_cntr *ibcc, u64 value)
+{
+	return efa_modify_event_counter(to_edev(ibcc->device), to_ecc(ibcc)->err_handle,
+					EFA_ADMIN_COUNTER_MODIFY_SET, value);
+}
+
+int efa_inc_comp_cntr(struct ib_comp_cntr *ibcc, u64 amount)
+{
+	return efa_modify_event_counter(to_edev(ibcc->device), to_ecc(ibcc)->comp_handle,
+					EFA_ADMIN_COUNTER_MODIFY_ADD, amount);
+}
+
+int efa_inc_err_comp_cntr(struct ib_comp_cntr *ibcc, u64 amount)
+{
+	return efa_modify_event_counter(to_edev(ibcc->device), to_ecc(ibcc)->err_handle,
+					EFA_ADMIN_COUNTER_MODIFY_ADD, amount);
+}
+
+static u32 efa_comp_cntr_op_to_comp_events(u32 op_mask)
+{
+	u32 events = 0;
+
+	if (op_mask & IB_UVERBS_COMP_CNTR_ATTACH_OP_SEND)
+		EFA_SET(&events, EFA_ADMIN_COUNTER_ATTACH_QP_EVENTS_SEND_COMP, 1);
+	if (op_mask & IB_UVERBS_COMP_CNTR_ATTACH_OP_RECV)
+		EFA_SET(&events, EFA_ADMIN_COUNTER_ATTACH_QP_EVENTS_RECV_COMP, 1);
+	if (op_mask & IB_UVERBS_COMP_CNTR_ATTACH_OP_RDMA_READ)
+		EFA_SET(&events, EFA_ADMIN_COUNTER_ATTACH_QP_EVENTS_READ_COMP, 1);
+	if (op_mask & IB_UVERBS_COMP_CNTR_ATTACH_OP_REMOTE_RDMA_READ)
+		EFA_SET(&events, EFA_ADMIN_COUNTER_ATTACH_QP_EVENTS_REMOTE_READ_COMP, 1);
+	if (op_mask & IB_UVERBS_COMP_CNTR_ATTACH_OP_RDMA_WRITE)
+		EFA_SET(&events, EFA_ADMIN_COUNTER_ATTACH_QP_EVENTS_WRITE_COMP, 1);
+	if (op_mask & IB_UVERBS_COMP_CNTR_ATTACH_OP_REMOTE_RDMA_WRITE)
+		EFA_SET(&events, EFA_ADMIN_COUNTER_ATTACH_QP_EVENTS_REMOTE_WRITE_COMP, 1);
+
+	return events;
+}
+
+static u32 efa_comp_cntr_op_to_err_events(u32 op_mask)
+{
+	u32 events = 0;
+
+	if (op_mask & IB_UVERBS_COMP_CNTR_ATTACH_OP_SEND)
+		EFA_SET(&events, EFA_ADMIN_COUNTER_ATTACH_QP_EVENTS_SEND_COMP_ERR, 1);
+	if (op_mask & IB_UVERBS_COMP_CNTR_ATTACH_OP_RECV)
+		EFA_SET(&events, EFA_ADMIN_COUNTER_ATTACH_QP_EVENTS_RECV_COMP_ERR, 1);
+	if (op_mask & IB_UVERBS_COMP_CNTR_ATTACH_OP_RDMA_READ)
+		EFA_SET(&events, EFA_ADMIN_COUNTER_ATTACH_QP_EVENTS_READ_COMP_ERR, 1);
+	if (op_mask & IB_UVERBS_COMP_CNTR_ATTACH_OP_RDMA_WRITE)
+		EFA_SET(&events, EFA_ADMIN_COUNTER_ATTACH_QP_EVENTS_WRITE_COMP_ERR, 1);
+
+	return events;
+}
+
+int efa_qp_attach_comp_cntr(struct ib_qp *ibqp, struct ib_comp_cntr *ibcc,
+			    struct ib_comp_cntr_attach_attr *attr)
+{
+	struct efa_com_attach_counter_params params;
+	struct efa_dev *dev = to_edev(ibqp->device);
+	struct efa_comp_cntr *cc = to_ecc(ibcc);
+	struct efa_qp *qp = to_eqp(ibqp);
+	int err;
+
+	params.cntr_handle = cc->comp_handle;
+	params.qp_handle = qp->qp_handle;
+	params.events = efa_comp_cntr_op_to_comp_events(attr->op_mask);
+
+	err = efa_com_attach_counter(&dev->edev, &params);
+	if (err)
+		return err;
+
+	params.cntr_handle = cc->err_handle;
+	params.events = efa_comp_cntr_op_to_err_events(attr->op_mask);
+
+	return efa_com_attach_counter(&dev->edev, &params);
+}
+
 DECLARE_UVERBS_NAMED_METHOD(EFA_IB_METHOD_MR_QUERY,
 			    UVERBS_ATTR_IDR(EFA_IB_ATTR_QUERY_MR_HANDLE,
 					    UVERBS_OBJECT_MR,
diff --git a/include/uapi/rdma/efa-abi.h b/include/uapi/rdma/efa-abi.h
index d5c18f8de182..492b2fa93467 100644
--- a/include/uapi/rdma/efa-abi.h
+++ b/include/uapi/rdma/efa-abi.h
@@ -133,6 +133,7 @@ enum {
 	EFA_QUERY_DEVICE_CAPS_RDMA_WRITE = 1 << 5,
 	EFA_QUERY_DEVICE_CAPS_UNSOLICITED_WRITE_RECV = 1 << 6,
 	EFA_QUERY_DEVICE_CAPS_CQ_WITH_EXT_MEM = 1 << 7,
+	EFA_QUERY_DEVICE_CAPS_COMP_CNTR = 1 << 8,
 };
 
 struct efa_ibv_ex_query_device_resp {
-- 
2.47.3


^ permalink raw reply related	[flat|nested] 14+ messages in thread

* Re: [PATCH for-next 1/4] RDMA/core: Add Completion Counters support
  2026-04-07 11:54 ` [PATCH for-next 1/4] RDMA/core: Add Completion Counters support Michael Margolin
@ 2026-04-07 14:17   ` Jason Gunthorpe
  2026-04-09 16:00     ` Michael Margolin
  0 siblings, 1 reply; 14+ messages in thread
From: Jason Gunthorpe @ 2026-04-07 14:17 UTC (permalink / raw)
  To: Michael Margolin
  Cc: leon, linux-rdma, sleybo, matua, gal.pressman, Yonatan Nachum

On Tue, Apr 07, 2026 at 11:54:21AM +0000, Michael Margolin wrote:
> +static int UVERBS_HANDLER(UVERBS_METHOD_COMP_CNTR_CREATE)(
> +	struct uverbs_attr_bundle *attrs)
> +{
> +	struct ib_uobject *uobj = uverbs_attr_get_uobject(
> +		attrs, UVERBS_ATTR_CREATE_COMP_CNTR_HANDLE);
> +	struct ib_device *ib_dev = attrs->context->device;
> +	struct ib_comp_cntr *cc;
> +	int ret;
> +
> +	if (!ib_dev->ops.create_comp_cntr ||
> +	    !ib_dev->ops.destroy_comp_cntr ||
> +	    !ib_dev->ops.qp_attach_comp_cntr)
> +		return -EOPNOTSUPP;
> +
> +	cc = rdma_zalloc_drv_obj(ib_dev, ib_comp_cntr);
> +	if (!cc)
> +		return -ENOMEM;
> +
> +	cc->device = ib_dev;
> +	cc->uobject = uobj;
> +
> +	ret = comp_cntr_get_umem(ib_dev, attrs,
> +				 UVERBS_ATTR_CREATE_COMP_CNTR_BUFFER_VA,
> +				 UVERBS_ATTR_CREATE_COMP_CNTR_BUFFER_FD,
> +				 UVERBS_ATTR_CREATE_COMP_CNTR_BUFFER_OFFSET,
> +				 &cc->comp_umem);
> +	if (ret)
> +		goto err_free;
> +
> +	ret = comp_cntr_get_umem(ib_dev, attrs,
> +				 UVERBS_ATTR_CREATE_COMP_CNTR_ERR_BUFFER_VA,
> +				 UVERBS_ATTR_CREATE_COMP_CNTR_ERR_BUFFER_FD,
> +				 UVERBS_ATTR_CREATE_COMP_CNTR_ERR_BUFFER_OFFSET,
> +				 &cc->err_umem);
> +	if (ret)
> +		goto err_comp_umem;

Seems a bit weird to have two things inside the object? Why not have
the counter support all events and if userspace wants two it can just
create two? There is alot of code to support this err/not err split..

Did any spec define the API this way?

Jason

^ permalink raw reply	[flat|nested] 14+ messages in thread

* Re: [PATCH for-next 1/4] RDMA/core: Add Completion Counters support
  2026-04-07 14:17   ` Jason Gunthorpe
@ 2026-04-09 16:00     ` Michael Margolin
  2026-04-09 16:13       ` Jason Gunthorpe
  0 siblings, 1 reply; 14+ messages in thread
From: Michael Margolin @ 2026-04-09 16:00 UTC (permalink / raw)
  To: Jason Gunthorpe
  Cc: leon, linux-rdma, sleybo, matua, gal.pressman, Yonatan Nachum

On Tue, Apr 07, 2026 at 11:17:31AM -0300, Jason Gunthorpe wrote:
> On Tue, Apr 07, 2026 at 11:54:21AM +0000, Michael Margolin wrote:
> > +static int UVERBS_HANDLER(UVERBS_METHOD_COMP_CNTR_CREATE)(
> > +	struct uverbs_attr_bundle *attrs)
> > +{
> > +	struct ib_uobject *uobj = uverbs_attr_get_uobject(
> > +		attrs, UVERBS_ATTR_CREATE_COMP_CNTR_HANDLE);
> > +	struct ib_device *ib_dev = attrs->context->device;
> > +	struct ib_comp_cntr *cc;
> > +	int ret;
> > +
> > +	if (!ib_dev->ops.create_comp_cntr ||
> > +	    !ib_dev->ops.destroy_comp_cntr ||
> > +	    !ib_dev->ops.qp_attach_comp_cntr)
> > +		return -EOPNOTSUPP;
> > +
> > +	cc = rdma_zalloc_drv_obj(ib_dev, ib_comp_cntr);
> > +	if (!cc)
> > +		return -ENOMEM;
> > +
> > +	cc->device = ib_dev;
> > +	cc->uobject = uobj;
> > +
> > +	ret = comp_cntr_get_umem(ib_dev, attrs,
> > +				 UVERBS_ATTR_CREATE_COMP_CNTR_BUFFER_VA,
> > +				 UVERBS_ATTR_CREATE_COMP_CNTR_BUFFER_FD,
> > +				 UVERBS_ATTR_CREATE_COMP_CNTR_BUFFER_OFFSET,
> > +				 &cc->comp_umem);
> > +	if (ret)
> > +		goto err_free;
> > +
> > +	ret = comp_cntr_get_umem(ib_dev, attrs,
> > +				 UVERBS_ATTR_CREATE_COMP_CNTR_ERR_BUFFER_VA,
> > +				 UVERBS_ATTR_CREATE_COMP_CNTR_ERR_BUFFER_FD,
> > +				 UVERBS_ATTR_CREATE_COMP_CNTR_ERR_BUFFER_OFFSET,
> > +				 &cc->err_umem);
> > +	if (ret)
> > +		goto err_comp_umem;
> 
> Seems a bit weird to have two things inside the object? Why not have
> the counter support all events and if userspace wants two it can just
> create two? There is alot of code to support this err/not err split..
> 
> Did any spec define the API this way?
> 
> Jason

EFA actually has a single counter object type that can count all events
as you suggest here, but I chose to define a single container for
success and error completion counts in core for three main reasons:

1. Consistency with userspace - we usually have a 1:1 mapping between
   rdma-core and kernel objects.

2. Although the UE spec does not define HW interfaces, it does couple
   success and error counting.

3. A single object for success and error completions gives more freedom
   to device implementations. For instance, it allows optimizing device
   HW resources by implementing the error counter in a less performant
   way.

I think the main code overhead is in the duplicate add, inc, and read
flows. We can reduce some of it by using a success/error enum instead,
though I personally prefer explicit functions.

Michael


^ permalink raw reply	[flat|nested] 14+ messages in thread

* Re: [PATCH for-next 1/4] RDMA/core: Add Completion Counters support
  2026-04-09 16:00     ` Michael Margolin
@ 2026-04-09 16:13       ` Jason Gunthorpe
  2026-04-09 17:29         ` Sean Hefty
  2026-04-09 18:36         ` Michael Margolin
  0 siblings, 2 replies; 14+ messages in thread
From: Jason Gunthorpe @ 2026-04-09 16:13 UTC (permalink / raw)
  To: Michael Margolin
  Cc: leon, linux-rdma, sleybo, matua, gal.pressman, Yonatan Nachum

On Thu, Apr 09, 2026 at 04:00:07PM +0000, Michael Margolin wrote:

> EFA actually has a single counter object type that can count all events
> as you suggest here, but I chose to define a single container for
> success and error completion counts in core for three main reasons:
> 
> 1. Consistency with userspace - we usually have a 1:1 mapping between
>    rdma-core and kernel objects.

Well here we would have two kernel objects right?

> 2. Although the UE spec does not define HW interfaces, it does couple
>    success and error counting.

It's just counting, it seem slike the api is you get a counter and
when certain events happen it counts. You get to pick what incrs that
counter.

> 3. A single object for success and error completions gives more freedom
>    to device implementations. For instance, it allows optimizing device
>    HW resources by implementing the error counter in a less performant
>    way.

This can be done anyhow by choosing fast/slow counters based on the
requested bits to count. If userspace requests an error only counter
it can be routed properly.

Jason

^ permalink raw reply	[flat|nested] 14+ messages in thread

* RE: [PATCH for-next 1/4] RDMA/core: Add Completion Counters support
  2026-04-09 16:13       ` Jason Gunthorpe
@ 2026-04-09 17:29         ` Sean Hefty
  2026-04-09 18:55           ` Jason Gunthorpe
  2026-04-09 18:36         ` Michael Margolin
  1 sibling, 1 reply; 14+ messages in thread
From: Sean Hefty @ 2026-04-09 17:29 UTC (permalink / raw)
  To: Jason Gunthorpe, Michael Margolin
  Cc: leon@kernel.org, linux-rdma@vger.kernel.org, sleybo@amazon.com,
	matua@amazon.com, gal.pressman@linux.dev, Yonatan Nachum

> > EFA actually has a single counter object type that can count all
> > events as you suggest here, but I chose to define a single container
> > for success and error completion counts in core for three main reasons:
> >
> > 1. Consistency with userspace - we usually have a 1:1 mapping between
> >    rdma-core and kernel objects.
> 
> Well here we would have two kernel objects right?
> 
> > 2. Although the UE spec does not define HW interfaces, it does couple
> >    success and error counting.
> 
> It's just counting, it seem slike the api is you get a counter and when certain
> events happen it counts. You get to pick what incrs that counter.
> 
> > 3. A single object for success and error completions gives more freedom
> >    to device implementations. For instance, it allows optimizing device
> >    HW resources by implementing the error counter in a less performant
> >    way.
> 
> This can be done anyhow by choosing fast/slow counters based on the requested
> bits to count. If userspace requests an error only counter it can be routed
> properly.

Portals and libfabric define success and error counters as a single entity.

The two counters have the same binding requirements, in that they count the same event (e.g. target of RDMA write).  One is simply incremented in case the operation fails.  I very conceptually think of how a WR will generate an error CQE even if the WR would not write a CQE in the success case.  Errors require special handling, but they aren't written to a separate CQ.

I view this as an implementation option.  One vendor may implement independent counters, which software can then piece together.  However, another implementation may have a tight coupling.  This is the CXI libfabric implementation:

			cmdq = cxi_cntr->domain->trig_cmdq;

			/* Use CQ to set a specific counter value */
			cmd.ct = cxi_cntr->ct->ctn;
			if (err) {
				cmd.set_ct_failure = 1;
				cmd.ct_failure = value;
			} else {
				cmd.set_ct_success = 1;
				cmd.ct_success = value;
			}

			ret = cxi_cq_emit_ct(cmdq->dev_cmdq, C_CMD_CT_SET,
					     &cmd);

It's hard for me to be certain, but it looks like CXI has a single HW object (cxi_cntr->ct->ctn) for both counters.

- Sean

^ permalink raw reply	[flat|nested] 14+ messages in thread

* Re: [PATCH for-next 1/4] RDMA/core: Add Completion Counters support
  2026-04-09 16:13       ` Jason Gunthorpe
  2026-04-09 17:29         ` Sean Hefty
@ 2026-04-09 18:36         ` Michael Margolin
  1 sibling, 0 replies; 14+ messages in thread
From: Michael Margolin @ 2026-04-09 18:36 UTC (permalink / raw)
  To: Jason Gunthorpe
  Cc: leon, linux-rdma, sleybo, matua, gal.pressman, Yonatan Nachum

On Thu, Apr 09, 2026 at 01:13:57PM -0300, Jason Gunthorpe wrote:
> On Thu, Apr 09, 2026 at 04:00:07PM +0000, Michael Margolin wrote:
> 
> > EFA actually has a single counter object type that can count all events
> > as you suggest here, but I chose to define a single container for
> > success and error completion counts in core for three main reasons:
> > 
> > 1. Consistency with userspace - we usually have a 1:1 mapping between
> >    rdma-core and kernel objects.
> 
> Well here we would have two kernel objects right?

In this patch it's a single kernel object that consists of two counters.
If I understand your suggestion right, we will have a single rdma-core
object backed by two kernel/device objects.
> 
> > 2. Although the UE spec does not define HW interfaces, it does couple
> >    success and error counting.
> 
> It's just counting, it seem slike the api is you get a counter and
> when certain events happen it counts. You get to pick what incrs that
> counter.

They are pretty aligned with Libfabric where completion counter is a
pair of success+error.
> 
> > 3. A single object for success and error completions gives more freedom
> >    to device implementations. For instance, it allows optimizing device
> >    HW resources by implementing the error counter in a less performant
> >    way.
> 
> This can be done anyhow by choosing fast/slow counters based on the
> requested bits to count. If userspace requests an error only counter
> it can be routed properly.

Then we might need to specify this early during creation to allow
certain optimizations.

I'm ok with your suggestion and agree it will simplify things on core
side but want to clarify that it might have a bit higher demands on
devices. What do you think?

Michael

^ permalink raw reply	[flat|nested] 14+ messages in thread

* Re: [PATCH for-next 1/4] RDMA/core: Add Completion Counters support
  2026-04-09 17:29         ` Sean Hefty
@ 2026-04-09 18:55           ` Jason Gunthorpe
  2026-04-09 19:15             ` Sean Hefty
  0 siblings, 1 reply; 14+ messages in thread
From: Jason Gunthorpe @ 2026-04-09 18:55 UTC (permalink / raw)
  To: Sean Hefty
  Cc: Michael Margolin, leon@kernel.org, linux-rdma@vger.kernel.org,
	sleybo@amazon.com, matua@amazon.com, gal.pressman@linux.dev,
	Yonatan Nachum

On Thu, Apr 09, 2026 at 05:29:28PM +0000, Sean Hefty wrote:

> I view this as an implementation option.  One vendor may implement
> independent counters, which software can then piece together.
> However, another implementation may have a tight coupling.  

Well, this is a problematic state to end up in when deciding the OS
and library abstraction. If we don't have joined counters then we
can't really support implementations that have tight coupling

But if we never see an implementation like that then we wasted our
efforts making them combined.

It seems like if portals and libfabric defined them as joined together
then we probably better support it that way too as someone probably
made HW like that.

Jason

^ permalink raw reply	[flat|nested] 14+ messages in thread

* RE: [PATCH for-next 1/4] RDMA/core: Add Completion Counters support
  2026-04-09 18:55           ` Jason Gunthorpe
@ 2026-04-09 19:15             ` Sean Hefty
  2026-04-09 19:44               ` Jason Gunthorpe
  0 siblings, 1 reply; 14+ messages in thread
From: Sean Hefty @ 2026-04-09 19:15 UTC (permalink / raw)
  To: Jason Gunthorpe
  Cc: Michael Margolin, leon@kernel.org, linux-rdma@vger.kernel.org,
	sleybo@amazon.com, matua@amazon.com, gal.pressman@linux.dev,
	Yonatan Nachum

> > I view this as an implementation option.  One vendor may implement
> > independent counters, which software can then piece together.
> > However, another implementation may have a tight coupling.
> 
> Well, this is a problematic state to end up in when deciding the OS and library
> abstraction. If we don't have joined counters then we can't really support
> implementations that have tight coupling
> 
> But if we never see an implementation like that then we wasted our efforts
> making them combined.
> 
> It seems like if portals and libfabric defined them as joined together then we
> probably better support it that way too as someone probably made HW like that.

Can we make this some general counter array, with properties applied to the array and no concern with how any specific entry might be used (at least from the view of the kernel)?

^ permalink raw reply	[flat|nested] 14+ messages in thread

* Re: [PATCH for-next 1/4] RDMA/core: Add Completion Counters support
  2026-04-09 19:15             ` Sean Hefty
@ 2026-04-09 19:44               ` Jason Gunthorpe
  2026-04-09 22:23                 ` Sean Hefty
  0 siblings, 1 reply; 14+ messages in thread
From: Jason Gunthorpe @ 2026-04-09 19:44 UTC (permalink / raw)
  To: Sean Hefty
  Cc: Michael Margolin, leon@kernel.org, linux-rdma@vger.kernel.org,
	sleybo@amazon.com, matua@amazon.com, gal.pressman@linux.dev,
	Yonatan Nachum

On Thu, Apr 09, 2026 at 07:15:31PM +0000, Sean Hefty wrote:
> > > I view this as an implementation option.  One vendor may implement
> > > independent counters, which software can then piece together.
> > > However, another implementation may have a tight coupling.
> > 
> > Well, this is a problematic state to end up in when deciding the OS and library
> > abstraction. If we don't have joined counters then we can't really support
> > implementations that have tight coupling
> > 
> > But if we never see an implementation like that then we wasted our efforts
> > making them combined.
> > 
> > It seems like if portals and libfabric defined them as joined together then we
> > probably better support it that way too as someone probably made HW like that.
> 
> Can we make this some general counter array, with properties applied
> to the array and no concern with how any specific entry might be
> used (at least from the view of the kernel)?

How does the API work? Who decides where the counter is stored?

Jason

^ permalink raw reply	[flat|nested] 14+ messages in thread

* RE: [PATCH for-next 1/4] RDMA/core: Add Completion Counters support
  2026-04-09 19:44               ` Jason Gunthorpe
@ 2026-04-09 22:23                 ` Sean Hefty
  0 siblings, 0 replies; 14+ messages in thread
From: Sean Hefty @ 2026-04-09 22:23 UTC (permalink / raw)
  To: Jason Gunthorpe
  Cc: Michael Margolin, leon@kernel.org, linux-rdma@vger.kernel.org,
	sleybo@amazon.com, matua@amazon.com, gal.pressman@linux.dev,
	Yonatan Nachum

> > > > I view this as an implementation option.  One vendor may implement
> > > > independent counters, which software can then piece together.
> > > > However, another implementation may have a tight coupling.
> > >
> > > Well, this is a problematic state to end up in when deciding the OS
> > > and library abstraction. If we don't have joined counters then we
> > > can't really support implementations that have tight coupling
> > >
> > > But if we never see an implementation like that then we wasted our
> > > efforts making them combined.
> > >
> > > It seems like if portals and libfabric defined them as joined
> > > together then we probably better support it that way too as someone
> probably made HW like that.
> >
> > Can we make this some general counter array, with properties applied
> > to the array and no concern with how any specific entry might be used
> > (at least from the view of the kernel)?
> 
> How does the API work? Who decides where the counter is stored?

The counters are treated as a group for the purposes of create/destroy/QP attach.  That is, they can't be individually configured.  However, they can be individually set/read, so instead of:

+       SET_DEVICE_OP(dev_ops, inc_comp_cntr);
+       SET_DEVICE_OP(dev_ops, inc_err_comp_cntr);

There's just one 'inc_comp_cntr' call that takes the group + an index.

- Sean

^ permalink raw reply	[flat|nested] 14+ messages in thread

end of thread, other threads:[~2026-04-09 22:23 UTC | newest]

Thread overview: 14+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2026-04-07 11:54 [PATCH for-next 0/4] Introduce Completion Counters Michael Margolin
2026-04-07 11:54 ` [PATCH for-next 1/4] RDMA/core: Add Completion Counters support Michael Margolin
2026-04-07 14:17   ` Jason Gunthorpe
2026-04-09 16:00     ` Michael Margolin
2026-04-09 16:13       ` Jason Gunthorpe
2026-04-09 17:29         ` Sean Hefty
2026-04-09 18:55           ` Jason Gunthorpe
2026-04-09 19:15             ` Sean Hefty
2026-04-09 19:44               ` Jason Gunthorpe
2026-04-09 22:23                 ` Sean Hefty
2026-04-09 18:36         ` Michael Margolin
2026-04-07 11:54 ` [PATCH for-next 2/4] RDMA/core: Add Completion Counters to resource tracking Michael Margolin
2026-04-07 11:54 ` [PATCH for-next 3/4] RDMA/efa: Update device interface Michael Margolin
2026-04-07 11:54 ` [PATCH for-next 4/4] RDMA/efa: Add Completion Counters support Michael Margolin

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox