Convert XRC to use xarray

PATCH Superseded Leon Romanovsky 5 participants 13 messages Jun 23, 2020 – Jul 3, 2020

Subsystems (2)

InfiniBand Mellanox MLX5 IB driver

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lore

Leon Romanovsky

author

2020-06-23 11:15 UTC #0 lore raw

cover Convert XRC to use xarray

From: Leon Romanovsky <[email protected]>

Changelog:
v1: Changed ib_dealloc_xrcd_user() do not iterate over tgt list, because it is expected to be empty.
v0: https://lore.kernel.org/lkml/[email protected]
Two small patches to simplify and improve XRC logic.

Thanks

Maor Gottlieb (2):
RDMA: Clean ib_alloc_xrcd() and reuse it to allocate XRC domain RDMA/core: Optimize XRC target lookup

 drivers/infiniband/core/uverbs_cmd.c | 12 ++---
 drivers/infiniband/core/verbs.c      | 76 +++++++++++++---------------
 drivers/infiniband/hw/mlx5/main.c    | 24 +++------
 include/rdma/ib_verbs.h              | 27 +++++-----
 4 files changed, 59 insertions(+), 80 deletions(-)

--
2.26.2

Leon Romanovsky

author

2020-06-23 11:15 UTC #1 lore raw

PATCH 1/2 RDMA: Clean ib_alloc_xrcd() and reuse it to allocate XRC domain

From: Maor Gottlieb <[email protected]>

ib_alloc_xrcd already does the required initialization, so move the mlx5 driver and uverbs to call it and save some code duplication, while cleaning the function argument lists of that function.

Signed-off-by Maor Gottlieb <[email protected]>

Signed-off-by Leon Romanovsky <[email protected]>

---
 drivers/infiniband/core/uverbs_cmd.c | 12 +++---------
 drivers/infiniband/core/verbs.c      | 19 +++++++++++++------
 drivers/infiniband/hw/mlx5/main.c    | 24 ++++++++----------------
 include/rdma/ib_verbs.h              | 22 ++++++++++++----------
 4 files changed, 36 insertions(+), 41 deletions(-)

drivers/infiniband/core/uverbs_cmd.c +3 -9

index 557644dcc923..68c9a0210220 100644
@@ -614,17 +614,11 @@ static int ib_uverbs_open_xrcd(struct uverbs_attr_bundle *attrs)
 	}
 
 	if (!xrcd) {
-		xrcd = ib_dev->ops.alloc_xrcd(ib_dev, &attrs->driver_udata);
+		xrcd = ib_alloc_xrcd_user(ib_dev, inode, &attrs->driver_udata);
 		if (IS_ERR(xrcd)) {
 			ret = PTR_ERR(xrcd);
 			goto err;
 		}
-
-		xrcd->inode   = inode;
-		xrcd->device  = ib_dev;
-		atomic_set(&xrcd->usecnt, 0);
-		mutex_init(&xrcd->tgt_qp_mutex);
-		INIT_LIST_HEAD(&xrcd->tgt_qp_list);
 		new_xrcd = 1;
 	}

@@ -663,7 +657,7 @@ static int ib_uverbs_open_xrcd(struct uverbs_attr_bundle *attrs)
 	}
 
 err_dealloc_xrcd:
-	ib_dealloc_xrcd(xrcd, uverbs_get_cleared_udata(attrs));
+	ib_dealloc_xrcd_user(xrcd, uverbs_get_cleared_udata(attrs));
 
 err:
 	uobj_alloc_abort(&obj->uobject, attrs);

@@ -701,7 +695,7 @@ int ib_uverbs_dealloc_xrcd(struct ib_uobject *uobject, struct ib_xrcd *xrcd,
 	if (inode && !atomic_dec_and_test(&xrcd->usecnt))
 		return 0;
 
-	ret = ib_dealloc_xrcd(xrcd, &attrs->driver_udata);
+	ret = ib_dealloc_xrcd_user(xrcd, &attrs->driver_udata);
 
 	if (ib_is_destroy_retryable(ret, why, uobject)) {
 		atomic_inc(&xrcd->usecnt);

drivers/infiniband/core/verbs.c +13 -6

index d70771caf534..d66a0ad62077 100644
@@ -2289,17 +2289,24 @@ int ib_detach_mcast(struct ib_qp *qp, union ib_gid *gid, u16 lid)
 }
 EXPORT_SYMBOL(ib_detach_mcast);
 
-struct ib_xrcd *__ib_alloc_xrcd(struct ib_device *device, const char *caller)
+/**
+ * ib_alloc_xrcd_user - Allocates an XRC domain.
+ * @device: The device on which to allocate the XRC domain.
+ * @inode: inode to connect XRCD
+ * @udata: Valid user data or NULL for kernel object
+ */
+struct ib_xrcd *ib_alloc_xrcd_user(struct ib_device *device,
+				   struct inode *inode, struct ib_udata *udata)
 {
 	struct ib_xrcd *xrcd;
 
 	if (!device->ops.alloc_xrcd)
 		return ERR_PTR(-EOPNOTSUPP);
 
-	xrcd = device->ops.alloc_xrcd(device, NULL);
+	xrcd = device->ops.alloc_xrcd(device, udata);
 	if (!IS_ERR(xrcd)) {
 		xrcd->device = device;
-		xrcd->inode = NULL;
+		xrcd->inode = inode;
 		atomic_set(&xrcd->usecnt, 0);
 		mutex_init(&xrcd->tgt_qp_mutex);
 		INIT_LIST_HEAD(&xrcd->tgt_qp_list);

@@ -2307,9 +2314,9 @@ struct ib_xrcd *__ib_alloc_xrcd(struct ib_device *device, const char *caller)
 
 	return xrcd;
 }
-EXPORT_SYMBOL(__ib_alloc_xrcd);
+EXPORT_SYMBOL(ib_alloc_xrcd_user);
 
-int ib_dealloc_xrcd(struct ib_xrcd *xrcd, struct ib_udata *udata)
+int ib_dealloc_xrcd_user(struct ib_xrcd *xrcd, struct ib_udata *udata)
 {
 	struct ib_qp *qp;
 	int ret;

@@ -2327,7 +2334,7 @@ int ib_dealloc_xrcd(struct ib_xrcd *xrcd, struct ib_udata *udata)
 
 	return xrcd->device->ops.dealloc_xrcd(xrcd, udata);
 }
-EXPORT_SYMBOL(ib_dealloc_xrcd);
+EXPORT_SYMBOL(ib_dealloc_xrcd_user);
 
 /**
  * ib_create_wq - Creates a WQ associated with the specified protection

drivers/infiniband/hw/mlx5/main.c +8 ~~-16~~

index 47a0c091eea5..46c596a855e7 100644
@@ -5043,27 +5043,17 @@ static int create_dev_resources(struct mlx5_ib_resources *devr)
 	if (ret)
 		goto err_create_cq;
 
-	devr->x0 = mlx5_ib_alloc_xrcd(&dev->ib_dev, NULL);
+	devr->x0 = ib_alloc_xrcd(&dev->ib_dev);
 	if (IS_ERR(devr->x0)) {
 		ret = PTR_ERR(devr->x0);
 		goto error2;
 	}
-	devr->x0->device = &dev->ib_dev;
-	devr->x0->inode = NULL;
-	atomic_set(&devr->x0->usecnt, 0);
-	mutex_init(&devr->x0->tgt_qp_mutex);
-	INIT_LIST_HEAD(&devr->x0->tgt_qp_list);
 
-	devr->x1 = mlx5_ib_alloc_xrcd(&dev->ib_dev, NULL);
+	devr->x1 = ib_alloc_xrcd(&dev->ib_dev);
 	if (IS_ERR(devr->x1)) {
 		ret = PTR_ERR(devr->x1);
 		goto error3;
 	}
-	devr->x1->device = &dev->ib_dev;
-	devr->x1->inode = NULL;
-	atomic_set(&devr->x1->usecnt, 0);
-	mutex_init(&devr->x1->tgt_qp_mutex);
-	INIT_LIST_HEAD(&devr->x1->tgt_qp_list);
 
 	memset(&attr, 0, sizeof(attr));
 	attr.attr.max_sge = 1;

@@ -5125,13 +5115,14 @@ static int create_dev_resources(struct mlx5_ib_resources *devr)
 error6:
 	kfree(devr->s1);
 error5:
+	atomic_dec(&devr->s0->ext.xrc.xrcd->usecnt);
 	mlx5_ib_destroy_srq(devr->s0, NULL);
 err_create:
 	kfree(devr->s0);
 error4:
-	mlx5_ib_dealloc_xrcd(devr->x1, NULL);
+	ib_dealloc_xrcd(devr->x1);
 error3:
-	mlx5_ib_dealloc_xrcd(devr->x0, NULL);
+	ib_dealloc_xrcd(devr->x0);
 error2:
 	mlx5_ib_destroy_cq(devr->c0, NULL);
 err_create_cq:

@@ -5149,10 +5140,11 @@ static void destroy_dev_resources(struct mlx5_ib_resources *devr)
 
 	mlx5_ib_destroy_srq(devr->s1, NULL);
 	kfree(devr->s1);
+	atomic_dec(&devr->s0->ext.xrc.xrcd->usecnt);
 	mlx5_ib_destroy_srq(devr->s0, NULL);
 	kfree(devr->s0);
-	mlx5_ib_dealloc_xrcd(devr->x0, NULL);
-	mlx5_ib_dealloc_xrcd(devr->x1, NULL);
+	ib_dealloc_xrcd(devr->x0);
+	ib_dealloc_xrcd(devr->x1);
 	mlx5_ib_destroy_cq(devr->c0, NULL);
 	kfree(devr->c0);
 	mlx5_ib_dealloc_pd(devr->p0, NULL);

include/rdma/ib_verbs.h +12 ~~-10~~

index f1e8afe1dd75..f785a4f1e58b 100644
@@ -4331,21 +4331,23 @@ int ib_attach_mcast(struct ib_qp *qp, union ib_gid *gid, u16 lid);
  */
 int ib_detach_mcast(struct ib_qp *qp, union ib_gid *gid, u16 lid);
 
-/**
- * ib_alloc_xrcd - Allocates an XRC domain.
- * @device: The device on which to allocate the XRC domain.
- * @caller: Module name for kernel consumers
- */
-struct ib_xrcd *__ib_alloc_xrcd(struct ib_device *device, const char *caller);
-#define ib_alloc_xrcd(device) \
-	__ib_alloc_xrcd((device), KBUILD_MODNAME)
+struct ib_xrcd *ib_alloc_xrcd_user(struct ib_device *device,
+				   struct inode *inode, struct ib_udata *udata);
+static inline struct ib_xrcd *ib_alloc_xrcd(struct ib_device *device)
+{
+	return ib_alloc_xrcd_user(device, NULL, NULL);
+}
 
 /**
- * ib_dealloc_xrcd - Deallocates an XRC domain.
+ * ib_dealloc_xrcd_user - Deallocates an XRC domain.
  * @xrcd: The XRC domain to deallocate.
  * @udata: Valid user data or NULL for kernel object
  */
-int ib_dealloc_xrcd(struct ib_xrcd *xrcd, struct ib_udata *udata);
+int ib_dealloc_xrcd_user(struct ib_xrcd *xrcd, struct ib_udata *udata);
+static inline int ib_dealloc_xrcd(struct ib_xrcd *xrcd)
+{
+	return ib_dealloc_xrcd_user(xrcd, NULL);
+}
 
 static inline int ib_check_mr_access(int flags)
 {

Signature · 1 line

2.26.2

Jason Gunthorpe

maintainer

2020-07-02 18:27 UTC #2 lore raw

Re: [PATCH rdma-next v1 1/2] RDMA: Clean ib_alloc_xrcd() and reuse it to allocate XRC domain

Quoted 157 lines · Leon Romanovsky

From: Maor Gottlieb <[email protected]>

ib_alloc_xrcd already does the required initialization, so move the mlx5 driver and uverbs to call it and save some code duplication, while cleaning the function argument lists of that function.

Signed-off-by Maor Gottlieb <[email protected]>

Signed-off-by Leon Romanovsky <[email protected]>

 drivers/infiniband/core/uverbs_cmd.c | 12 +++---------
 drivers/infiniband/core/verbs.c      | 19 +++++++++++++------
 drivers/infiniband/hw/mlx5/main.c    | 24 ++++++++----------------
 include/rdma/ib_verbs.h              | 22 ++++++++++++----------
 4 files changed, 36 insertions(+), 41 deletions(-)

drivers/infiniband/core/uverbs_cmd.c +4 -9

index 557644dcc923..68c9a0210220 100644
+++ b/drivers/infiniband/core/uverbs_cmd.c

@@ -614,17 +614,11 @@ static int ib_uverbs_open_xrcd(struct uverbs_attr_bundle *attrs)
 	}
 
 	if (!xrcd) {
-		xrcd = ib_dev->ops.alloc_xrcd(ib_dev, &attrs->driver_udata);
+		xrcd = ib_alloc_xrcd_user(ib_dev, inode, &attrs->driver_udata);
 		if (IS_ERR(xrcd)) {
 			ret = PTR_ERR(xrcd);
 			goto err;
 		}
-
-		xrcd->inode   = inode;
-		xrcd->device  = ib_dev;
-		atomic_set(&xrcd->usecnt, 0);
-		mutex_init(&xrcd->tgt_qp_mutex);
-		INIT_LIST_HEAD(&xrcd->tgt_qp_list);
 		new_xrcd = 1;
 	}

@@ -663,7 +657,7 @@ static int ib_uverbs_open_xrcd(struct uverbs_attr_bundle *attrs)
 	}
 
 err_dealloc_xrcd:
-	ib_dealloc_xrcd(xrcd, uverbs_get_cleared_udata(attrs));
+	ib_dealloc_xrcd_user(xrcd, uverbs_get_cleared_udata(attrs));
 
 err:
 	uobj_alloc_abort(&obj->uobject, attrs);

@@ -701,7 +695,7 @@ int ib_uverbs_dealloc_xrcd(struct ib_uobject *uobject, struct ib_xrcd *xrcd,
 	if (inode && !atomic_dec_and_test(&xrcd->usecnt))
 		return 0;
 
-	ret = ib_dealloc_xrcd(xrcd, &attrs->driver_udata);
+	ret = ib_dealloc_xrcd_user(xrcd, &attrs->driver_udata);
 
 	if (ib_is_destroy_retryable(ret, why, uobject)) {
 		atomic_inc(&xrcd->usecnt);

drivers/infiniband/core/verbs.c +14 -6

index d70771caf534..d66a0ad62077 100644
+++ b/drivers/infiniband/core/verbs.c

@@ -2289,17 +2289,24 @@ int ib_detach_mcast(struct ib_qp *qp, union ib_gid *gid, u16 lid)
 }
 EXPORT_SYMBOL(ib_detach_mcast);
 
-struct ib_xrcd *__ib_alloc_xrcd(struct ib_device *device, const char *caller)
+/**
+ * ib_alloc_xrcd_user - Allocates an XRC domain.
+ * @device: The device on which to allocate the XRC domain.
+ * @inode: inode to connect XRCD
+ * @udata: Valid user data or NULL for kernel object
+ */
+struct ib_xrcd *ib_alloc_xrcd_user(struct ib_device *device,
+				   struct inode *inode, struct ib_udata *udata)
 {
 	struct ib_xrcd *xrcd;
 
 	if (!device->ops.alloc_xrcd)
 		return ERR_PTR(-EOPNOTSUPP);
 
-	xrcd = device->ops.alloc_xrcd(device, NULL);
+	xrcd = device->ops.alloc_xrcd(device, udata);
 	if (!IS_ERR(xrcd)) {
 		xrcd->device = device;
-		xrcd->inode = NULL;
+		xrcd->inode = inode;
 		atomic_set(&xrcd->usecnt, 0);
 		mutex_init(&xrcd->tgt_qp_mutex);
 		INIT_LIST_HEAD(&xrcd->tgt_qp_list);

@@ -2307,9 +2314,9 @@ struct ib_xrcd *__ib_alloc_xrcd(struct ib_device *device, const char *caller)
 
 	return xrcd;
 }
-EXPORT_SYMBOL(__ib_alloc_xrcd);
+EXPORT_SYMBOL(ib_alloc_xrcd_user);
 
-int ib_dealloc_xrcd(struct ib_xrcd *xrcd, struct ib_udata *udata)
+int ib_dealloc_xrcd_user(struct ib_xrcd *xrcd, struct ib_udata *udata)
 {
 	struct ib_qp *qp;
 	int ret;

@@ -2327,7 +2334,7 @@ int ib_dealloc_xrcd(struct ib_xrcd *xrcd, struct ib_udata *udata)
 
 	return xrcd->device->ops.dealloc_xrcd(xrcd, udata);
 }
-EXPORT_SYMBOL(ib_dealloc_xrcd);
+EXPORT_SYMBOL(ib_dealloc_xrcd_user);
 
 /**
  * ib_create_wq - Creates a WQ associated with the specified protection

drivers/infiniband/hw/mlx5/main.c +6 ~~-14~~

index 47a0c091eea5..46c596a855e7 100644
+++ b/drivers/infiniband/hw/mlx5/main.c

@@ -5043,27 +5043,17 @@ static int create_dev_resources(struct mlx5_ib_resources *devr)
 	if (ret)
 		goto err_create_cq;
 
-	devr->x0 = mlx5_ib_alloc_xrcd(&dev->ib_dev, NULL);
+	devr->x0 = ib_alloc_xrcd(&dev->ib_dev);
 	if (IS_ERR(devr->x0)) {
 		ret = PTR_ERR(devr->x0);
 		goto error2;
 	}
-	devr->x0->device = &dev->ib_dev;
-	devr->x0->inode = NULL;
-	atomic_set(&devr->x0->usecnt, 0);
-	mutex_init(&devr->x0->tgt_qp_mutex);
-	INIT_LIST_HEAD(&devr->x0->tgt_qp_list);
 
-	devr->x1 = mlx5_ib_alloc_xrcd(&dev->ib_dev, NULL);
+	devr->x1 = ib_alloc_xrcd(&dev->ib_dev);
 	if (IS_ERR(devr->x1)) {
 		ret = PTR_ERR(devr->x1);
 		goto error3;
 	}
-	devr->x1->device = &dev->ib_dev;
-	devr->x1->inode = NULL;
-	atomic_set(&devr->x1->usecnt, 0);
-	mutex_init(&devr->x1->tgt_qp_mutex);
-	INIT_LIST_HEAD(&devr->x1->tgt_qp_list);
 
 	memset(&attr, 0, sizeof(attr));
 	attr.attr.max_sge = 1;

@@ -5125,13 +5115,14 @@ static int create_dev_resources(struct mlx5_ib_resources *devr)
 error6:
 	kfree(devr->s1);
 error5:
+	atomic_dec(&devr->s0->ext.xrc.xrcd->usecnt);
 	mlx5_ib_destroy_srq(devr->s0, NULL);
 err_create:
 	kfree(devr->s0);
 error4:
-	mlx5_ib_dealloc_xrcd(devr->x1, NULL);
+	ib_dealloc_xrcd(devr->x1);
 error3:
-	mlx5_ib_dealloc_xrcd(devr->x0, NULL);
+	ib_dealloc_xrcd(devr->x0);
 error2:
 	mlx5_ib_destroy_cq(devr->c0, NULL);
 err_create_cq:

drivers/infiniband/hw/mlx5/main.c static void destroy_dev_resources(struct mlx5_ib_resources *devr) · line 5147

Quoted 10 lines

drivers/infiniband/hw/mlx5/main.c +3 -2

@@ -5149,10 +5140,11 @@ static void destroy_dev_resources(struct mlx5_ib_resources *devr)
 
 	mlx5_ib_destroy_srq(devr->s1, NULL);
 	kfree(devr->s1);
+	atomic_dec(&devr->s0->ext.xrc.xrcd->usecnt);
 	mlx5_ib_destroy_srq(devr->s0, NULL);
 	kfree(devr->s0);
-	mlx5_ib_dealloc_xrcd(devr->x0, NULL);
-	mlx5_ib_dealloc_xrcd(devr->x1, NULL);
+	ib_dealloc_xrcd(devr->x0);
+	ib_dealloc_xrcd(devr->x1);

Why is this an improvement? Whatever this internal driver thing is, it is not a visible XRCD..

In fact why use an ib_xrcd here at all when this only needs the xrcdn? Just call the mlx_cmd_xrcd_* directly.

drivers/infiniband/hw/mlx5/main.c static void destroy_dev_resources(struct mlx5_ib_resources *devr)

Quoted 6 lines

drivers/infiniband/hw/mlx5/main.c +6 -0

+struct ib_xrcd *ib_alloc_xrcd_user(struct ib_device *device,
+				   struct inode *inode, struct ib_udata *udata);
+static inline struct ib_xrcd *ib_alloc_xrcd(struct ib_device *device)
+{
+	return ib_alloc_xrcd_user(device, NULL, NULL);
+}

Because other than the above there is no in-kernel user of XRCD and this can all be deleted, the uverbs_cmd can directly create the xrcd and call the driver like for other non-kernel objects.

Jason

Leon Romanovsky

author

2020-07-03 06:25 UTC #3 lore raw

Re: [PATCH rdma-next v1 1/2] RDMA: Clean ib_alloc_xrcd() and reuse it to allocate XRC domain

Quoted 172 lines · Jason Gunthorpe

Quoted 157 lines · Leon Romanovsky

From: Maor Gottlieb <[email protected]>

ib_alloc_xrcd already does the required initialization, so move the mlx5 driver and uverbs to call it and save some code duplication, while cleaning the function argument lists of that function.

Signed-off-by Maor Gottlieb <[email protected]>

Signed-off-by Leon Romanovsky <[email protected]>

 drivers/infiniband/core/uverbs_cmd.c | 12 +++---------
 drivers/infiniband/core/verbs.c      | 19 +++++++++++++------
 drivers/infiniband/hw/mlx5/main.c    | 24 ++++++++----------------
 include/rdma/ib_verbs.h              | 22 ++++++++++++----------
 4 files changed, 36 insertions(+), 41 deletions(-)

drivers/infiniband/core/uverbs_cmd.c +4 -9

index 557644dcc923..68c9a0210220 100644
+++ b/drivers/infiniband/core/uverbs_cmd.c

@@ -614,17 +614,11 @@ static int ib_uverbs_open_xrcd(struct uverbs_attr_bundle *attrs)
 	}
 
 	if (!xrcd) {
-		xrcd = ib_dev->ops.alloc_xrcd(ib_dev, &attrs->driver_udata);
+		xrcd = ib_alloc_xrcd_user(ib_dev, inode, &attrs->driver_udata);
 		if (IS_ERR(xrcd)) {
 			ret = PTR_ERR(xrcd);
 			goto err;
 		}
-
-		xrcd->inode   = inode;
-		xrcd->device  = ib_dev;
-		atomic_set(&xrcd->usecnt, 0);
-		mutex_init(&xrcd->tgt_qp_mutex);
-		INIT_LIST_HEAD(&xrcd->tgt_qp_list);
 		new_xrcd = 1;
 	}

@@ -663,7 +657,7 @@ static int ib_uverbs_open_xrcd(struct uverbs_attr_bundle *attrs)
 	}
 
 err_dealloc_xrcd:
-	ib_dealloc_xrcd(xrcd, uverbs_get_cleared_udata(attrs));
+	ib_dealloc_xrcd_user(xrcd, uverbs_get_cleared_udata(attrs));
 
 err:
 	uobj_alloc_abort(&obj->uobject, attrs);

@@ -701,7 +695,7 @@ int ib_uverbs_dealloc_xrcd(struct ib_uobject *uobject, struct ib_xrcd *xrcd,
 	if (inode && !atomic_dec_and_test(&xrcd->usecnt))
 		return 0;
 
-	ret = ib_dealloc_xrcd(xrcd, &attrs->driver_udata);
+	ret = ib_dealloc_xrcd_user(xrcd, &attrs->driver_udata);
 
 	if (ib_is_destroy_retryable(ret, why, uobject)) {
 		atomic_inc(&xrcd->usecnt);

drivers/infiniband/core/verbs.c +14 -6

index d70771caf534..d66a0ad62077 100644
+++ b/drivers/infiniband/core/verbs.c

@@ -2289,17 +2289,24 @@ int ib_detach_mcast(struct ib_qp *qp, union ib_gid *gid, u16 lid)
 }
 EXPORT_SYMBOL(ib_detach_mcast);
 
-struct ib_xrcd *__ib_alloc_xrcd(struct ib_device *device, const char *caller)
+/**
+ * ib_alloc_xrcd_user - Allocates an XRC domain.
+ * @device: The device on which to allocate the XRC domain.
+ * @inode: inode to connect XRCD
+ * @udata: Valid user data or NULL for kernel object
+ */
+struct ib_xrcd *ib_alloc_xrcd_user(struct ib_device *device,
+				   struct inode *inode, struct ib_udata *udata)
 {
 	struct ib_xrcd *xrcd;
 
 	if (!device->ops.alloc_xrcd)
 		return ERR_PTR(-EOPNOTSUPP);
 
-	xrcd = device->ops.alloc_xrcd(device, NULL);
+	xrcd = device->ops.alloc_xrcd(device, udata);
 	if (!IS_ERR(xrcd)) {
 		xrcd->device = device;
-		xrcd->inode = NULL;
+		xrcd->inode = inode;
 		atomic_set(&xrcd->usecnt, 0);
 		mutex_init(&xrcd->tgt_qp_mutex);
 		INIT_LIST_HEAD(&xrcd->tgt_qp_list);

@@ -2307,9 +2314,9 @@ struct ib_xrcd *__ib_alloc_xrcd(struct ib_device *device, const char *caller)
 
 	return xrcd;
 }
-EXPORT_SYMBOL(__ib_alloc_xrcd);
+EXPORT_SYMBOL(ib_alloc_xrcd_user);
 
-int ib_dealloc_xrcd(struct ib_xrcd *xrcd, struct ib_udata *udata)
+int ib_dealloc_xrcd_user(struct ib_xrcd *xrcd, struct ib_udata *udata)
 {
 	struct ib_qp *qp;
 	int ret;

@@ -2327,7 +2334,7 @@ int ib_dealloc_xrcd(struct ib_xrcd *xrcd, struct ib_udata *udata)
 
 	return xrcd->device->ops.dealloc_xrcd(xrcd, udata);
 }
-EXPORT_SYMBOL(ib_dealloc_xrcd);
+EXPORT_SYMBOL(ib_dealloc_xrcd_user);
 
 /**
  * ib_create_wq - Creates a WQ associated with the specified protection

drivers/infiniband/hw/mlx5/main.c +6 ~~-14~~

index 47a0c091eea5..46c596a855e7 100644
+++ b/drivers/infiniband/hw/mlx5/main.c

@@ -5043,27 +5043,17 @@ static int create_dev_resources(struct mlx5_ib_resources *devr)
 	if (ret)
 		goto err_create_cq;
 
-	devr->x0 = mlx5_ib_alloc_xrcd(&dev->ib_dev, NULL);
+	devr->x0 = ib_alloc_xrcd(&dev->ib_dev);
 	if (IS_ERR(devr->x0)) {
 		ret = PTR_ERR(devr->x0);
 		goto error2;
 	}
-	devr->x0->device = &dev->ib_dev;
-	devr->x0->inode = NULL;
-	atomic_set(&devr->x0->usecnt, 0);
-	mutex_init(&devr->x0->tgt_qp_mutex);
-	INIT_LIST_HEAD(&devr->x0->tgt_qp_list);
 
-	devr->x1 = mlx5_ib_alloc_xrcd(&dev->ib_dev, NULL);
+	devr->x1 = ib_alloc_xrcd(&dev->ib_dev);
 	if (IS_ERR(devr->x1)) {
 		ret = PTR_ERR(devr->x1);
 		goto error3;
 	}
-	devr->x1->device = &dev->ib_dev;
-	devr->x1->inode = NULL;
-	atomic_set(&devr->x1->usecnt, 0);
-	mutex_init(&devr->x1->tgt_qp_mutex);
-	INIT_LIST_HEAD(&devr->x1->tgt_qp_list);
 
 	memset(&attr, 0, sizeof(attr));
 	attr.attr.max_sge = 1;

@@ -5125,13 +5115,14 @@ static int create_dev_resources(struct mlx5_ib_resources *devr)
 error6:
 	kfree(devr->s1);
 error5:
+	atomic_dec(&devr->s0->ext.xrc.xrcd->usecnt);
 	mlx5_ib_destroy_srq(devr->s0, NULL);
 err_create:
 	kfree(devr->s0);
 error4:
-	mlx5_ib_dealloc_xrcd(devr->x1, NULL);
+	ib_dealloc_xrcd(devr->x1);
 error3:
-	mlx5_ib_dealloc_xrcd(devr->x0, NULL);
+	ib_dealloc_xrcd(devr->x0);
 error2:
 	mlx5_ib_destroy_cq(devr->c0, NULL);
 err_create_cq:

drivers/infiniband/hw/mlx5/main.c static void destroy_dev_resources(struct mlx5_ib_resources *devr) · line 5147

Quoted 10 lines

drivers/infiniband/hw/mlx5/main.c +3 -2

@@ -5149,10 +5140,11 @@ static void destroy_dev_resources(struct mlx5_ib_resources *devr)
 
 	mlx5_ib_destroy_srq(devr->s1, NULL);
 	kfree(devr->s1);
+	atomic_dec(&devr->s0->ext.xrc.xrcd->usecnt);
 	mlx5_ib_destroy_srq(devr->s0, NULL);
 	kfree(devr->s0);
-	mlx5_ib_dealloc_xrcd(devr->x0, NULL);
-	mlx5_ib_dealloc_xrcd(devr->x1, NULL);
+	ib_dealloc_xrcd(devr->x0);
+	ib_dealloc_xrcd(devr->x1);

Why is this an improvement? Whatever this internal driver thing is, it is not a visible XRCD..

Quoted 2 lines

In fact why use an ib_xrcd here at all when this only needs the xrcdn? Just call the mlx_cmd_xrcd_* directly.

This is proper IB object and IMHO it should be created with standard primitives, so we will be able account them properly and see full HW objects picture without need to go and combine pieces from driver and ib_core.

The code properly hardcoded same thing as ib_core does for XRCD, which is right way to do instead of making half of work like you are proposing.

At some point of time, XRCD will be visible in rdmatool too and we will be able to RAW query even internal driver objects, because they are standard ones.

Maybe, one day, we will be able to move mlx5_ib_handle_internal_error() to general code.

Quoted 11 lines

drivers/infiniband/hw/mlx5/main.c static void destroy_dev_resources(struct mlx5_ib_resources *devr)
Quoted 7 lines
drivers/infiniband/hw/mlx5/main.c +6 -0
+struct ib_xrcd *ib_alloc_xrcd_user(struct ib_device *device,
+				   struct inode *inode, struct ib_udata *udata);
+static inline struct ib_xrcd *ib_alloc_xrcd(struct ib_device *device)
+{
+	return ib_alloc_xrcd_user(device, NULL, NULL);
+}
Because other than the above there is no in-kernel user of XRCD and this can all be deleted, the uverbs_cmd can directly create the xrcd and call the driver like for other non-kernel objects.

I can call directly to ib_alloc_xrcd_user() from mlx5, but I still prefer to use ib_core primitives as much as possible.

Thanks

Quoted 2 lines

Jason

Jason Gunthorpe

maintainer

2020-07-03 12:00 UTC #4 lore raw

Re: [PATCH rdma-next v1 1/2] RDMA: Clean ib_alloc_xrcd() and reuse it to allocate XRC domain

Quoted 9 lines · Leon Romanovsky

Quoted 5 lines
Why is this an improvement? Whatever this internal driver thing is, it is not a visible XRCD..
In fact why use an ib_xrcd here at all when this only needs the xrcdn? Just call the mlx_cmd_xrcd_* directly.
This is proper IB object and IMHO it should be created with standard primitives, so we will be able account them properly and see full HW objects picture without need to go and combine pieces from driver and ib_core.

I'm not sure it is a proper IB object, it is some weird driver internal thing, and I couldn't guess what it is being used for. Why are user QPs being associated with a driver internal XRCD?

The key thing here is that it is never actaully used with any other core API expecting an xrcd, only the driver specific xrcdn is extracted and used in a few places.

Further it doesn't even act like an core xrcd, QPs being attached to it are not recorded in the lists, the refcounts are not incrd, etc.

So even if you did expose it over rdmatool the whole thing would be an inconsistent mess that doesn't reflect the expected configuration of a real xrcd.

Jason

Leon Romanovsky

author

2020-06-23 11:15 UTC #5 lore raw

PATCH 2/2 RDMA/core: Optimize XRC target lookup

In reply to Leon Romanovsky

From: Maor Gottlieb <[email protected]>

Replace the mutex with read write semaphore and use xarray instead of linked list for XRC target QPs. This will give faster XRC target lookup. In addition, when QP is closed, don't insert it back to the xarray if the destroy command failed.

Signed-off-by Maor Gottlieb <[email protected]>

Signed-off-by Leon Romanovsky <[email protected]>

---
 drivers/infiniband/core/verbs.c | 57 ++++++++++++---------------------
 include/rdma/ib_verbs.h         |  5 ++-
 2 files changed, 23 insertions(+), 39 deletions(-)

drivers/infiniband/core/verbs.c +21 ~~-36~~

index d66a0ad62077..1ccbe43e33cd 100644
@@ -1090,13 +1090,6 @@ static void __ib_shared_qp_event_handler(struct ib_event *event, void *context)
 	spin_unlock_irqrestore(&qp->device->qp_open_list_lock, flags);
 }
 
-static void __ib_insert_xrcd_qp(struct ib_xrcd *xrcd, struct ib_qp *qp)
-{
-	mutex_lock(&xrcd->tgt_qp_mutex);
-	list_add(&qp->xrcd_list, &xrcd->tgt_qp_list);
-	mutex_unlock(&xrcd->tgt_qp_mutex);
-}
-
 static struct ib_qp *__ib_open_qp(struct ib_qp *real_qp,
 				  void (*event_handler)(struct ib_event *, void *),
 				  void *qp_context)

@@ -1139,16 +1132,15 @@ struct ib_qp *ib_open_qp(struct ib_xrcd *xrcd,
 	if (qp_open_attr->qp_type != IB_QPT_XRC_TGT)
 		return ERR_PTR(-EINVAL);
 
-	qp = ERR_PTR(-EINVAL);
-	mutex_lock(&xrcd->tgt_qp_mutex);
-	list_for_each_entry(real_qp, &xrcd->tgt_qp_list, xrcd_list) {
-		if (real_qp->qp_num == qp_open_attr->qp_num) {
-			qp = __ib_open_qp(real_qp, qp_open_attr->event_handler,
-					  qp_open_attr->qp_context);
-			break;
-		}
+	down_read(&xrcd->tgt_qps_rwsem);
+	real_qp = xa_load(&xrcd->tgt_qps, qp_open_attr->qp_num);
+	if (!real_qp) {
+		up_read(&xrcd->tgt_qps_rwsem);
+		return ERR_PTR(-EINVAL);
 	}
-	mutex_unlock(&xrcd->tgt_qp_mutex);
+	qp = __ib_open_qp(real_qp, qp_open_attr->event_handler,
+			  qp_open_attr->qp_context);
+	up_read(&xrcd->tgt_qps_rwsem);
 	return qp;
 }
 EXPORT_SYMBOL(ib_open_qp);

@@ -1157,6 +1149,7 @@ static struct ib_qp *create_xrc_qp_user(struct ib_qp *qp,
 					struct ib_qp_init_attr *qp_init_attr)
 {
 	struct ib_qp *real_qp = qp;
+	int err;
 
 	qp->event_handler = __ib_shared_qp_event_handler;
 	qp->qp_context = qp;

@@ -1172,7 +1165,12 @@ static struct ib_qp *create_xrc_qp_user(struct ib_qp *qp,
 	if (IS_ERR(qp))
 		return qp;
 
-	__ib_insert_xrcd_qp(qp_init_attr->xrcd, real_qp);
+	err = xa_err(xa_store(&qp_init_attr->xrcd->tgt_qps, real_qp->qp_num,
+			      real_qp, GFP_KERNEL));
+	if (err) {
+		ib_close_qp(qp);
+		return ERR_PTR(err);
+	}
 	return qp;
 }

@@ -1888,21 +1886,18 @@ static int __ib_destroy_shared_qp(struct ib_qp *qp)
 
 	real_qp = qp->real_qp;
 	xrcd = real_qp->xrcd;
-
-	mutex_lock(&xrcd->tgt_qp_mutex);
+	down_write(&xrcd->tgt_qps_rwsem);
 	ib_close_qp(qp);
 	if (atomic_read(&real_qp->usecnt) == 0)
-		list_del(&real_qp->xrcd_list);
+		xa_erase(&xrcd->tgt_qps, real_qp->qp_num);
 	else
 		real_qp = NULL;
-	mutex_unlock(&xrcd->tgt_qp_mutex);
+	up_write(&xrcd->tgt_qps_rwsem);
 
 	if (real_qp) {
 		ret = ib_destroy_qp(real_qp);
 		if (!ret)
 			atomic_dec(&xrcd->usecnt);
-		else
-			__ib_insert_xrcd_qp(xrcd, real_qp);
 	}
 
 	return 0;

@@ -2308,8 +2303,8 @@ struct ib_xrcd *ib_alloc_xrcd_user(struct ib_device *device,
 		xrcd->device = device;
 		xrcd->inode = inode;
 		atomic_set(&xrcd->usecnt, 0);
-		mutex_init(&xrcd->tgt_qp_mutex);
-		INIT_LIST_HEAD(&xrcd->tgt_qp_list);
+		init_rwsem(&xrcd->tgt_qps_rwsem);
+		xa_init(&xrcd->tgt_qps);
 	}
 
 	return xrcd;

@@ -2318,20 +2313,10 @@ EXPORT_SYMBOL(ib_alloc_xrcd_user);
 
 int ib_dealloc_xrcd_user(struct ib_xrcd *xrcd, struct ib_udata *udata)
 {
-	struct ib_qp *qp;
-	int ret;
-
 	if (atomic_read(&xrcd->usecnt))
 		return -EBUSY;
 
-	while (!list_empty(&xrcd->tgt_qp_list)) {
-		qp = list_entry(xrcd->tgt_qp_list.next, struct ib_qp, xrcd_list);
-		ret = ib_destroy_qp(qp);
-		if (ret)
-			return ret;
-	}
-	mutex_destroy(&xrcd->tgt_qp_mutex);
-
+	WARN_ON(!xa_empty(&xrcd->tgt_qps));
 	return xrcd->device->ops.dealloc_xrcd(xrcd, udata);
 }
 EXPORT_SYMBOL(ib_dealloc_xrcd_user);

include/rdma/ib_verbs.h +2 -3

index f785a4f1e58b..9b973b3b6f4c 100644
@@ -1568,9 +1568,8 @@ struct ib_xrcd {
 	struct ib_device       *device;
 	atomic_t		usecnt; /* count all exposed resources */
 	struct inode	       *inode;
-
-	struct mutex		tgt_qp_mutex;
-	struct list_head	tgt_qp_list;
+	struct rw_semaphore	tgt_qps_rwsem;
+	struct xarray		tgt_qps;
 };
 
 struct ib_ah {

Signature · 1 line

2.26.2

Jason Gunthorpe

maintainer

2020-06-23 17:52 UTC #6 lore raw

Re: [PATCH rdma-next v1 2/2] RDMA/core: Optimize XRC target lookup

Quoted 35 lines · Leon Romanovsky

From: Maor Gottlieb <[email protected]>

Signed-off-by Maor Gottlieb <[email protected]>

Signed-off-by Leon Romanovsky <[email protected]>

 drivers/infiniband/core/verbs.c | 57 ++++++++++++---------------------
 include/rdma/ib_verbs.h         |  5 ++-
 2 files changed, 23 insertions(+), 39 deletions(-)

drivers/infiniband/core/verbs.c +1 -8

index d66a0ad62077..1ccbe43e33cd 100644
+++ b/drivers/infiniband/core/verbs.c

@@ -1090,13 +1090,6 @@ static void __ib_shared_qp_event_handler(struct ib_event *event, void *context)
 	spin_unlock_irqrestore(&qp->device->qp_open_list_lock, flags);
 }
 
-static void __ib_insert_xrcd_qp(struct ib_xrcd *xrcd, struct ib_qp *qp)
-{
-	mutex_lock(&xrcd->tgt_qp_mutex);
-	list_add(&qp->xrcd_list, &xrcd->tgt_qp_list);
-	mutex_unlock(&xrcd->tgt_qp_mutex);
-}
-
 static struct ib_qp *__ib_open_qp(struct ib_qp *real_qp,
 				  void (*event_handler)(struct ib_event *, void *),
 				  void *qp_context)

@@ -1139,16 +1132,15 @@ struct ib_qp *ib_open_qp(struct ib_xrcd *xrcd,
 	if (qp_open_attr->qp_type != IB_QPT_XRC_TGT)
 		return ERR_PTR(-EINVAL);
 
-	qp = ERR_PTR(-EINVAL);

drivers/infiniband/core/verbs.c struct ib_qp *ib_open_qp(struct ib_xrcd *xrcd, · line 1137

Quoted 10 lines

drivers/infiniband/core/verbs.c +3 -7

-	mutex_lock(&xrcd->tgt_qp_mutex);
-	list_for_each_entry(real_qp, &xrcd->tgt_qp_list, xrcd_list) {
-		if (real_qp->qp_num == qp_open_attr->qp_num) {
-			qp = __ib_open_qp(real_qp, qp_open_attr->event_handler,
-					  qp_open_attr->qp_context);
-			break;
-		}
+	down_read(&xrcd->tgt_qps_rwsem);
+	real_qp = xa_load(&xrcd->tgt_qps, qp_open_attr->qp_num);
+	if (!real_qp) {

Don't we already have a xarray indexed against qp_num in res_track? Can we use it somehow?

Jason

Leon Romanovsky

author

2020-06-23 18:15 UTC #7 lore raw

Re: [PATCH rdma-next v1 2/2] RDMA/core: Optimize XRC target lookup

Quoted 35 lines · Jason Gunthorpe

Quoted 34 lines · Leon Romanovsky

From: Maor Gottlieb <[email protected]>

Signed-off-by Maor Gottlieb <[email protected]>

Signed-off-by Leon Romanovsky <[email protected]>

 drivers/infiniband/core/verbs.c | 57 ++++++++++++---------------------
 include/rdma/ib_verbs.h         |  5 ++-
 2 files changed, 23 insertions(+), 39 deletions(-)

drivers/infiniband/core/verbs.c +1 -7

index d66a0ad62077..1ccbe43e33cd 100644
+++ b/drivers/infiniband/core/verbs.c

@@ -1090,13 +1090,6 @@ static void __ib_shared_qp_event_handler(struct ib_event *event, void *context)
 	spin_unlock_irqrestore(&qp->device->qp_open_list_lock, flags);
 }
 
-static void __ib_insert_xrcd_qp(struct ib_xrcd *xrcd, struct ib_qp *qp)
-{
-	mutex_lock(&xrcd->tgt_qp_mutex);
-	list_add(&qp->xrcd_list, &xrcd->tgt_qp_list);
-	mutex_unlock(&xrcd->tgt_qp_mutex);
-}
-
 static struct ib_qp *__ib_open_qp(struct ib_qp *real_qp,
 				  void (*event_handler)(struct ib_event *, void *),
 				  void *qp_context)

@@ -1139,16 +1132,15 @@ struct ib_qp *ib_open_qp(struct ib_xrcd *xrcd,
 	if (qp_open_attr->qp_type != IB_QPT_XRC_TGT)
 		return ERR_PTR(-EINVAL);

Quoted 14 lines

drivers/infiniband/core/verbs.c struct ib_qp *ib_open_qp(struct ib_xrcd *xrcd, · line 1137
Quoted 11 lines
drivers/infiniband/core/verbs.c +3 -8
-	qp = ERR_PTR(-EINVAL);
-	mutex_lock(&xrcd->tgt_qp_mutex);
-	list_for_each_entry(real_qp, &xrcd->tgt_qp_list, xrcd_list) {
-		if (real_qp->qp_num == qp_open_attr->qp_num) {
-			qp = __ib_open_qp(real_qp, qp_open_attr->event_handler,
-					  qp_open_attr->qp_context);
-			break;
-		}
+	down_read(&xrcd->tgt_qps_rwsem);
+	real_qp = xa_load(&xrcd->tgt_qps, qp_open_attr->qp_num);
+	if (!real_qp) {
Don't we already have a xarray indexed against qp_num in res_track? Can we use it somehow?

We don't have restrack for XRC, we will need somehow manage QP-to-XRC connection there.

Thanks

Quoted 2 lines

Jason

Jason Gunthorpe

2020-06-23 18:49 UTC #8 lore raw

Re: [PATCH rdma-next v1 2/2] RDMA/core: Optimize XRC target lookup

Quoted 51 lines · Leon Romanovsky

Quoted 35 lines · Jason Gunthorpe
Quoted 34 lines · Leon Romanovsky
From: Maor Gottlieb <[email protected]>
Replace the mutex with read write semaphore and use xarray instead of linked list for XRC target QPs. This will give faster XRC target lookup. In addition, when QP is closed, don't insert it back to the xarray if the destroy command failed.
Signed-off-by Maor Gottlieb <[email protected]>
Signed-off-by Leon Romanovsky <[email protected]>
 drivers/infiniband/core/verbs.c | 57 ++++++++++++---------------------
 include/rdma/ib_verbs.h         |  5 ++-
 2 files changed, 23 insertions(+), 39 deletions(-)
drivers/infiniband/core/verbs.c +1 -7
index d66a0ad62077..1ccbe43e33cd 100644
+++ b/drivers/infiniband/core/verbs.c
@@ -1090,13 +1090,6 @@ static void __ib_shared_qp_event_handler(struct ib_event *event, void *context)
 	spin_unlock_irqrestore(&qp->device->qp_open_list_lock, flags);
 }
 
-static void __ib_insert_xrcd_qp(struct ib_xrcd *xrcd, struct ib_qp *qp)
-{
-	mutex_lock(&xrcd->tgt_qp_mutex);
-	list_add(&qp->xrcd_list, &xrcd->tgt_qp_list);
-	mutex_unlock(&xrcd->tgt_qp_mutex);
-}
-
 static struct ib_qp *__ib_open_qp(struct ib_qp *real_qp,
 				  void (*event_handler)(struct ib_event *, void *),
 				  void *qp_context)
@@ -1139,16 +1132,15 @@ struct ib_qp *ib_open_qp(struct ib_xrcd *xrcd,
 	if (qp_open_attr->qp_type != IB_QPT_XRC_TGT)
 		return ERR_PTR(-EINVAL);
 
Quoted 14 lines
drivers/infiniband/core/verbs.c struct ib_qp *ib_open_qp(struct ib_xrcd *xrcd, · line 1137
Quoted 11 lines
drivers/infiniband/core/verbs.c +3 -8
-	qp = ERR_PTR(-EINVAL);
-	mutex_lock(&xrcd->tgt_qp_mutex);
-	list_for_each_entry(real_qp, &xrcd->tgt_qp_list, xrcd_list) {
-		if (real_qp->qp_num == qp_open_attr->qp_num) {
-			qp = __ib_open_qp(real_qp, qp_open_attr->event_handler,
-					  qp_open_attr->qp_context);
-			break;
-		}
+	down_read(&xrcd->tgt_qps_rwsem);
+	real_qp = xa_load(&xrcd->tgt_qps, qp_open_attr->qp_num);
+	if (!real_qp) {
Don't we already have a xarray indexed against qp_num in res_track? Can we use it somehow?

Quoted 2 lines

We don't have restrack for XRC, we will need somehow manage QP-to-XRC connection there.

It is not xrc, this is just looking up a qp and checking if it is part of the xrcd

Jason

Maor Gottlieb

2020-06-24 10:42 UTC #9 lore raw

Re: [PATCH rdma-next v1 2/2] RDMA/core: Optimize XRC target lookup

Quoted 50 lines · Jason Gunthorpe

Quoted 49 lines · Leon Romanovsky
Quoted 48 lines · Jason Gunthorpe
Quoted 35 lines · Leon Romanovsky
From: Maor Gottlieb <[email protected]>
Replace the mutex with read write semaphore and use xarray instead of linked list for XRC target QPs. This will give faster XRC target lookup. In addition, when QP is closed, don't insert it back to the xarray if the destroy command failed.
Signed-off-by Maor Gottlieb <[email protected]>
Signed-off-by Leon Romanovsky <[email protected]>
  drivers/infiniband/core/verbs.c | 57 ++++++++++++---------------------
  include/rdma/ib_verbs.h         |  5 ++-
  2 files changed, 23 insertions(+), 39 deletions(-)
drivers/infiniband/core/verbs.c +1 -8
index d66a0ad62077..1ccbe43e33cd 100644
+++ b/drivers/infiniband/core/verbs.c
@@ -1090,13 +1090,6 @@ static void __ib_shared_qp_event_handler(struct ib_event *event, void *context)
  	spin_unlock_irqrestore(&qp->device->qp_open_list_lock, flags);
  }
 
-static void __ib_insert_xrcd_qp(struct ib_xrcd *xrcd, struct ib_qp *qp)
-{
-	mutex_lock(&xrcd->tgt_qp_mutex);
-	list_add(&qp->xrcd_list, &xrcd->tgt_qp_list);
-	mutex_unlock(&xrcd->tgt_qp_mutex);
-}
-
  static struct ib_qp *__ib_open_qp(struct ib_qp *real_qp,
  				  void (*event_handler)(struct ib_event *, void *),
  				  void *qp_context)
@@ -1139,16 +1132,15 @@ struct ib_qp *ib_open_qp(struct ib_xrcd *xrcd,
  	if (qp_open_attr->qp_type != IB_QPT_XRC_TGT)
  		return ERR_PTR(-EINVAL);
 
-	qp = ERR_PTR(-EINVAL);
drivers/infiniband/core/verbs.c struct ib_qp *ib_open_qp(struct ib_xrcd *xrcd, · line 1137
Quoted 10 lines
drivers/infiniband/core/verbs.c +3 -7
-	mutex_lock(&xrcd->tgt_qp_mutex);
-	list_for_each_entry(real_qp, &xrcd->tgt_qp_list, xrcd_list) {
-		if (real_qp->qp_num == qp_open_attr->qp_num) {
-			qp = __ib_open_qp(real_qp, qp_open_attr->event_handler,
-					  qp_open_attr->qp_context);
-			break;
-		}
+	down_read(&xrcd->tgt_qps_rwsem);
+	real_qp = xa_load(&xrcd->tgt_qps, qp_open_attr->qp_num);
+	if (!real_qp) {
Don't we already have a xarray indexed against qp_num in res_track? Can we use it somehow?

Quoted 6 lines

Quoted 2 lines
We don't have restrack for XRC, we will need somehow manage QP-to-XRC connection there.
It is not xrc, this is just looking up a qp and checking if it is part of the xrcd
Jason

It's the XRC target QP and it is not tracked.

Jason Gunthorpe

2020-06-24 14:00 UTC #10 lore raw

Re: [PATCH rdma-next v1 2/2] RDMA/core: Optimize XRC target lookup

Quoted 52 lines · Maor Gottlieb

Quoted 50 lines · Jason Gunthorpe
Quoted 49 lines · Leon Romanovsky
Quoted 48 lines · Jason Gunthorpe
Quoted 35 lines · Leon Romanovsky
From: Maor Gottlieb <[email protected]>
Replace the mutex with read write semaphore and use xarray instead of linked list for XRC target QPs. This will give faster XRC target lookup. In addition, when QP is closed, don't insert it back to the xarray if the destroy command failed.
Signed-off-by Maor Gottlieb <[email protected]>
Signed-off-by Leon Romanovsky <[email protected]>
  drivers/infiniband/core/verbs.c | 57 ++++++++++++---------------------
  include/rdma/ib_verbs.h         |  5 ++-
  2 files changed, 23 insertions(+), 39 deletions(-)
drivers/infiniband/core/verbs.c +1 -8
index d66a0ad62077..1ccbe43e33cd 100644
+++ b/drivers/infiniband/core/verbs.c
@@ -1090,13 +1090,6 @@ static void __ib_shared_qp_event_handler(struct ib_event *event, void *context)
  	spin_unlock_irqrestore(&qp->device->qp_open_list_lock, flags);
  }
 
-static void __ib_insert_xrcd_qp(struct ib_xrcd *xrcd, struct ib_qp *qp)
-{
-	mutex_lock(&xrcd->tgt_qp_mutex);
-	list_add(&qp->xrcd_list, &xrcd->tgt_qp_list);
-	mutex_unlock(&xrcd->tgt_qp_mutex);
-}
-
  static struct ib_qp *__ib_open_qp(struct ib_qp *real_qp,
  				  void (*event_handler)(struct ib_event *, void *),
  				  void *qp_context)
@@ -1139,16 +1132,15 @@ struct ib_qp *ib_open_qp(struct ib_xrcd *xrcd,
  	if (qp_open_attr->qp_type != IB_QPT_XRC_TGT)
  		return ERR_PTR(-EINVAL);
 
-	qp = ERR_PTR(-EINVAL);
drivers/infiniband/core/verbs.c struct ib_qp *ib_open_qp(struct ib_xrcd *xrcd, · line 1137
Quoted 10 lines
drivers/infiniband/core/verbs.c +3 -7
-	mutex_lock(&xrcd->tgt_qp_mutex);
-	list_for_each_entry(real_qp, &xrcd->tgt_qp_list, xrcd_list) {
-		if (real_qp->qp_num == qp_open_attr->qp_num) {
-			qp = __ib_open_qp(real_qp, qp_open_attr->event_handler,
-					  qp_open_attr->qp_context);
-			break;
-		}
+	down_read(&xrcd->tgt_qps_rwsem);
+	real_qp = xa_load(&xrcd->tgt_qps, qp_open_attr->qp_num);
+	if (!real_qp) {
Don't we already have a xarray indexed against qp_num in res_track? Can we use it somehow?

Quoted 8 lines

Quoted 6 lines
Quoted 2 lines
We don't have restrack for XRC, we will need somehow manage QP-to-XRC connection there.
It is not xrc, this is just looking up a qp and checking if it is part of the xrcd
Jason
It's the XRC target QP and it is not tracked.

Really? Something called 'real_qp' isn't stored in the restrack? Doesn't that sound like a bug already?

Jason

Maor Gottlieb

2020-06-24 14:48 UTC #11 lore raw

Re: [PATCH rdma-next v1 2/2] RDMA/core: Optimize XRC target lookup

Quoted 57 lines · Jason Gunthorpe

Quoted 56 lines · Maor Gottlieb
Quoted 55 lines · Jason Gunthorpe
Quoted 49 lines · Leon Romanovsky
Quoted 35 lines · Jason Gunthorpe
Quoted 34 lines · Leon Romanovsky
From: Maor Gottlieb <[email protected]>
Replace the mutex with read write semaphore and use xarray instead of linked list for XRC target QPs. This will give faster XRC target lookup. In addition, when QP is closed, don't insert it back to the xarray if the destroy command failed.
Signed-off-by Maor Gottlieb <[email protected]>
Signed-off-by Leon Romanovsky <[email protected]>
   drivers/infiniband/core/verbs.c | 57 ++++++++++++---------------------
   include/rdma/ib_verbs.h         |  5 ++-
   2 files changed, 23 insertions(+), 39 deletions(-)
drivers/infiniband/core/verbs.c +1 -7
index d66a0ad62077..1ccbe43e33cd 100644
+++ b/drivers/infiniband/core/verbs.c
@@ -1090,13 +1090,6 @@ static void __ib_shared_qp_event_handler(struct ib_event *event, void *context)
   	spin_unlock_irqrestore(&qp->device->qp_open_list_lock, flags);
   }
 
-static void __ib_insert_xrcd_qp(struct ib_xrcd *xrcd, struct ib_qp *qp)
-{
-	mutex_lock(&xrcd->tgt_qp_mutex);
-	list_add(&qp->xrcd_list, &xrcd->tgt_qp_list);
-	mutex_unlock(&xrcd->tgt_qp_mutex);
-}
-
   static struct ib_qp *__ib_open_qp(struct ib_qp *real_qp,
   				  void (*event_handler)(struct ib_event *, void *),
   				  void *qp_context)
@@ -1139,16 +1132,15 @@ struct ib_qp *ib_open_qp(struct ib_xrcd *xrcd,
   	if (qp_open_attr->qp_type != IB_QPT_XRC_TGT)
   		return ERR_PTR(-EINVAL);
 
Quoted 13 lines
drivers/infiniband/core/verbs.c struct ib_qp *ib_open_qp(struct ib_xrcd *xrcd, · line 1137
Quoted 11 lines
drivers/infiniband/core/verbs.c +3 -8
-	qp = ERR_PTR(-EINVAL);
-	mutex_lock(&xrcd->tgt_qp_mutex);
-	list_for_each_entry(real_qp, &xrcd->tgt_qp_list, xrcd_list) {
-		if (real_qp->qp_num == qp_open_attr->qp_num) {
-			qp = __ib_open_qp(real_qp, qp_open_attr->event_handler,
-					  qp_open_attr->qp_context);
-			break;
-		}
+	down_read(&xrcd->tgt_qps_rwsem);
+	real_qp = xa_load(&xrcd->tgt_qps, qp_open_attr->qp_num);
+	if (!real_qp) {
Don't we already have a xarray indexed against qp_num in res_track? Can we use it somehow?
Quoted 2 lines
We don't have restrack for XRC, we will need somehow manage QP-to-XRC connection there.
It is not xrc, this is just looking up a qp and checking if it is part of the xrcd

Quoted 6 lines

Quoted 2 lines
Quoted 1 line
Jason
It's the XRC target QP and it is not tracked.
Really? Something called 'real_qp' isn't stored in the restrack? Doesn't that sound like a bug already?
Jason

Bug / limitation. see the below comment from core_priv.h:

        /*
         * We don't track XRC QPs for now, because they don't have PD
         * and more importantly they are created internaly by driver,
         * see mlx5 create_dev_resources() as an example. */

Leon, the PD is a real limitation? regarding the second part (mlx5), you just sent patches that change it,right?

Leon Romanovsky

author

2020-06-25 08:26 UTC #12 lore raw

Re: [PATCH rdma-next v1 2/2] RDMA/core: Optimize XRC target lookup

Quoted 68 lines · Maor Gottlieb

Quoted 57 lines · Jason Gunthorpe
Quoted 56 lines · Maor Gottlieb
Quoted 55 lines · Jason Gunthorpe
Quoted 49 lines · Leon Romanovsky
Quoted 35 lines · Jason Gunthorpe
Quoted 34 lines · Leon Romanovsky
From: Maor Gottlieb <[email protected]>
Replace the mutex with read write semaphore and use xarray instead of linked list for XRC target QPs. This will give faster XRC target lookup. In addition, when QP is closed, don't insert it back to the xarray if the destroy command failed.
Signed-off-by Maor Gottlieb <[email protected]>
Signed-off-by Leon Romanovsky <[email protected]>
   drivers/infiniband/core/verbs.c | 57 ++++++++++++---------------------
   include/rdma/ib_verbs.h         |  5 ++-
   2 files changed, 23 insertions(+), 39 deletions(-)
drivers/infiniband/core/verbs.c +1 -7
index d66a0ad62077..1ccbe43e33cd 100644
+++ b/drivers/infiniband/core/verbs.c
@@ -1090,13 +1090,6 @@ static void __ib_shared_qp_event_handler(struct ib_event *event, void *context)
   	spin_unlock_irqrestore(&qp->device->qp_open_list_lock, flags);
   }
 
-static void __ib_insert_xrcd_qp(struct ib_xrcd *xrcd, struct ib_qp *qp)
-{
-	mutex_lock(&xrcd->tgt_qp_mutex);
-	list_add(&qp->xrcd_list, &xrcd->tgt_qp_list);
-	mutex_unlock(&xrcd->tgt_qp_mutex);
-}
-
   static struct ib_qp *__ib_open_qp(struct ib_qp *real_qp,
   				  void (*event_handler)(struct ib_event *, void *),
   				  void *qp_context)
@@ -1139,16 +1132,15 @@ struct ib_qp *ib_open_qp(struct ib_xrcd *xrcd,
   	if (qp_open_attr->qp_type != IB_QPT_XRC_TGT)
   		return ERR_PTR(-EINVAL);
 
Quoted 13 lines
drivers/infiniband/core/verbs.c struct ib_qp *ib_open_qp(struct ib_xrcd *xrcd, · line 1137
Quoted 11 lines
drivers/infiniband/core/verbs.c +3 -8
-	qp = ERR_PTR(-EINVAL);
-	mutex_lock(&xrcd->tgt_qp_mutex);
-	list_for_each_entry(real_qp, &xrcd->tgt_qp_list, xrcd_list) {
-		if (real_qp->qp_num == qp_open_attr->qp_num) {
-			qp = __ib_open_qp(real_qp, qp_open_attr->event_handler,
-					  qp_open_attr->qp_context);
-			break;
-		}
+	down_read(&xrcd->tgt_qps_rwsem);
+	real_qp = xa_load(&xrcd->tgt_qps, qp_open_attr->qp_num);
+	if (!real_qp) {
Don't we already have a xarray indexed against qp_num in res_track? Can we use it somehow?
Quoted 2 lines
We don't have restrack for XRC, we will need somehow manage QP-to-XRC connection there.
It is not xrc, this is just looking up a qp and checking if it is part of the xrcd
Quoted 6 lines
Quoted 2 lines
Quoted 1 line
Jason
It's the XRC target QP and it is not tracked.
Really? Something called 'real_qp' isn't stored in the restrack? Doesn't that sound like a bug already?
Jason
Bug / limitation. see the below comment from core_priv.h:

Quoted 8 lines

        /*
         * We don't track XRC QPs for now, because they don't have PD
         * and more importantly they are created internaly by driver,
         * see mlx5 create_dev_resources() as an example. */
Leon, the PD is a real limitation? regarding the second part (mlx5), you just sent patches that change it,right?

The second part is not relevant now, but the first part is still relevant, due to the check in restrack.c.

  131         case RDMA_RESTRACK_QP:
  132                 pd = container_of(res, struct ib_qp, res)->pd;
  133                 if (!pd) {
  134                         WARN_ONCE(true, "XRC QPs are not supported\n");
  135                         /* Survive, despite the programmer's error */
  136                         res->kern_name = " ";
  137                 }
  138                 break;

The reason to it that "regular" QPs has the name of their "creator" inside PD which doesn't exist for XRC. It is possible to change and make special case for the XRC, but all places that touch "kern_name" need to be audited.

It is in my roadmap after allocation work will be finished and we will introduce proper reference counting for the QPs.

Thanks

Quoted 1 line