Commit a5417864 authored by Chengchang Tang's avatar Chengchang Tang Committed by Juan Zhou
Browse files

RDMA/hns: Add method for shrinking DCA memory pool 

driver inclusion
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/I9CK0O



--------------------------------------------------------------------------

If no QP is using a DCA mem object, the userspace driver can destroy it.
So add a new method 'HNS_IB_METHOD_DCA_MEM_SHRINK' to allow the userspace
dirver to remove an object from DCA memory pool.

If a DCA mem object has been shrunk, the userspace driver can destroy it
by 'HNS_IB_METHOD_DCA_MEM_DEREG' method and free the buffer which is
allocated in userspace.

Signed-off-by: default avatarChengchang Tang <tangchengchang@huawei.com>
parent 2543c70a

drivers/infiniband/hw/hns/hns_roce_dca.c

+145 −1
Original line number Diff line number Diff line
@@ -35,6 +35,16 @@ struct dca_mem_attr { 
	u32 size;

};



static inline bool dca_page_is_free(struct hns_dca_page_state *state)

{

	return state->buf_id == HNS_DCA_INVALID_BUF_ID;

}



static inline bool dca_mem_is_available(struct dca_mem *mem)

{

	return mem->flags == (DCA_MEM_FLAGS_ALLOCED | DCA_MEM_FLAGS_REGISTERED);

}



static void *alloc_dca_pages(struct hns_roce_dev *hr_dev, struct dca_mem *mem,

			     struct dca_mem_attr *attr)

{
@@ -88,6 +98,41 @@ static struct hns_dca_page_state *alloc_dca_states(void *pages, int count) 
	return states;

}



#define DCA_MEM_STOP_ITERATE -1

#define DCA_MEM_NEXT_ITERATE -2

static void travel_dca_pages(struct hns_roce_dca_ctx *ctx, void *param,

			     int (*cb)(struct dca_mem *, int, void *))

{

	struct dca_mem *mem, *tmp;

	unsigned long flags;

	bool avail;

	int ret;

	int i;



	spin_lock_irqsave(&ctx->pool_lock, flags);

	list_for_each_entry_safe(mem, tmp, &ctx->pool, list) {

		spin_unlock_irqrestore(&ctx->pool_lock, flags);



		spin_lock(&mem->lock);

		avail = dca_mem_is_available(mem);

		ret = 0;

		for (i = 0; avail && i < mem->page_count; i++) {

			ret = cb(mem, i, param);

			if (ret == DCA_MEM_STOP_ITERATE ||

			    ret == DCA_MEM_NEXT_ITERATE)

				break;

		}

		spin_unlock(&mem->lock);

		spin_lock_irqsave(&ctx->pool_lock, flags);



		if (ret == DCA_MEM_STOP_ITERATE)

			goto done;

	}



done:

	spin_unlock_irqrestore(&ctx->pool_lock, flags);

}



/* user DCA is managed by ucontext */

static inline struct hns_roce_dca_ctx *

to_hr_dca_ctx(struct hns_roce_ucontext *uctx)
@@ -159,6 +204,63 @@ static int register_dca_mem(struct hns_roce_dev *hr_dev, 
	return 0;

}



struct dca_mem_shrink_attr {

	u64 shrink_key;

	u32 shrink_mems;

};



static int shrink_dca_page_proc(struct dca_mem *mem, int index, void *param)

{

	struct dca_mem_shrink_attr *attr = param;

	struct hns_dca_page_state *state;

	int i, free_pages;



	free_pages = 0;

	for (i = 0; i < mem->page_count; i++) {

		state = &mem->states[i];

		if (dca_page_is_free(state))

			free_pages++;

	}



	/* No pages are in use */

	if (free_pages == mem->page_count) {

		/* unregister first empty DCA mem */

		if (!attr->shrink_mems) {

			mem->flags &= ~DCA_MEM_FLAGS_REGISTERED;

			attr->shrink_key = mem->key;

		}



		attr->shrink_mems++;

	}



	if (attr->shrink_mems > 1)

		return DCA_MEM_STOP_ITERATE;

	else

		return DCA_MEM_NEXT_ITERATE;

}



static int shrink_dca_mem(struct hns_roce_dev *hr_dev,

			  struct hns_roce_ucontext *uctx, u64 reserved_size,

			  struct hns_dca_shrink_resp *resp)

{

	struct hns_roce_dca_ctx *ctx = to_hr_dca_ctx(uctx);

	struct dca_mem_shrink_attr attr = {};

	unsigned long flags;

	bool need_shink;



	spin_lock_irqsave(&ctx->pool_lock, flags);

	need_shink = ctx->free_mems > 0 && ctx->free_size > reserved_size;

	spin_unlock_irqrestore(&ctx->pool_lock, flags);

	if (!need_shink)

		return 0;



	travel_dca_pages(ctx, &attr, shrink_dca_page_proc);

	resp->free_mems = attr.shrink_mems;

	resp->free_key = attr.shrink_key;



	return 0;

}



static void init_dca_context(struct hns_roce_dca_ctx *ctx)

{

	INIT_LIST_HEAD(&ctx->pool);
@@ -339,10 +441,52 @@ DECLARE_UVERBS_NAMED_METHOD_DESTROY( 
	UVERBS_ATTR_IDR(HNS_IB_ATTR_DCA_MEM_DEREG_HANDLE, HNS_IB_OBJECT_DCA_MEM,

			UVERBS_ACCESS_DESTROY, UA_MANDATORY));



static int UVERBS_HANDLER(HNS_IB_METHOD_DCA_MEM_SHRINK)(

	struct uverbs_attr_bundle *attrs)

{

	struct hns_roce_ucontext *uctx = uverbs_attr_to_hr_uctx(attrs);

	struct hns_dca_shrink_resp resp = {};

	u64 reserved_size = 0;

	int ret;



	ret = uverbs_copy_from(&reserved_size, attrs,

			       HNS_IB_ATTR_DCA_MEM_SHRINK_RESERVED_SIZE);

	if (ret)

		return ret;



	ret = shrink_dca_mem(to_hr_dev(uctx->ibucontext.device), uctx,

			     reserved_size, &resp);

	if (ret)

		return ret;



	ret = uverbs_copy_to(attrs, HNS_IB_ATTR_DCA_MEM_SHRINK_OUT_FREE_KEY,

			     &resp.free_key, sizeof(resp.free_key));

	if (!ret)

		ret = uverbs_copy_to(attrs,

				     HNS_IB_ATTR_DCA_MEM_SHRINK_OUT_FREE_MEMS,

				     &resp.free_mems, sizeof(resp.free_mems));

	if (ret)

		return ret;



	return 0;

}



DECLARE_UVERBS_NAMED_METHOD(

	HNS_IB_METHOD_DCA_MEM_SHRINK,

	UVERBS_ATTR_IDR(HNS_IB_ATTR_DCA_MEM_SHRINK_HANDLE,

			HNS_IB_OBJECT_DCA_MEM, UVERBS_ACCESS_WRITE,

			UA_MANDATORY),

	UVERBS_ATTR_PTR_IN(HNS_IB_ATTR_DCA_MEM_SHRINK_RESERVED_SIZE,

			   UVERBS_ATTR_TYPE(u64), UA_MANDATORY),

	UVERBS_ATTR_PTR_OUT(HNS_IB_ATTR_DCA_MEM_SHRINK_OUT_FREE_KEY,

			    UVERBS_ATTR_TYPE(u64), UA_MANDATORY),

	UVERBS_ATTR_PTR_OUT(HNS_IB_ATTR_DCA_MEM_SHRINK_OUT_FREE_MEMS,

			    UVERBS_ATTR_TYPE(u32), UA_MANDATORY));

DECLARE_UVERBS_NAMED_OBJECT(HNS_IB_OBJECT_DCA_MEM,

			    UVERBS_TYPE_ALLOC_IDR(dca_cleanup),

			    &UVERBS_METHOD(HNS_IB_METHOD_DCA_MEM_REG),

			    &UVERBS_METHOD(HNS_IB_METHOD_DCA_MEM_DEREG));

			    &UVERBS_METHOD(HNS_IB_METHOD_DCA_MEM_DEREG),

			    &UVERBS_METHOD(HNS_IB_METHOD_DCA_MEM_SHRINK));



static bool dca_is_supported(struct ib_device *device)

{

drivers/infiniband/hw/hns/hns_roce_dca.h

+7 −0
Original line number Diff line number Diff line
@@ -18,6 +18,13 @@ struct hns_dca_page_state { 


extern const struct uapi_definition hns_roce_dca_uapi_defs[];



struct hns_dca_shrink_resp {

	u64 free_key; /* free buffer's key which registered by the user */

	u32 free_mems; /* free buffer count which no any QP be using */

};



#define HNS_DCA_INVALID_BUF_ID 0UL



void hns_roce_register_udca(struct hns_roce_dev *hr_dev,

			    struct hns_roce_ucontext *uctx);

void hns_roce_unregister_udca(struct hns_roce_dev *hr_dev,

include/uapi/rdma/hns-abi.h

+8 −0
Original line number Diff line number Diff line
@@ -170,6 +170,7 @@ enum hns_ib_objects { 
enum hns_ib_dca_mem_methods {

	HNS_IB_METHOD_DCA_MEM_REG = (1U << UVERBS_ID_NS_SHIFT),

	HNS_IB_METHOD_DCA_MEM_DEREG,

	HNS_IB_METHOD_DCA_MEM_SHRINK,

};



enum hns_ib_dca_mem_reg_attrs {
@@ -183,4 +184,11 @@ enum hns_ib_dca_mem_dereg_attrs { 
	HNS_IB_ATTR_DCA_MEM_DEREG_HANDLE = (1U << UVERBS_ID_NS_SHIFT),

};



enum hns_ib_dca_mem_shrink_attrs {

	HNS_IB_ATTR_DCA_MEM_SHRINK_HANDLE = (1U << UVERBS_ID_NS_SHIFT),

	HNS_IB_ATTR_DCA_MEM_SHRINK_RESERVED_SIZE,

	HNS_IB_ATTR_DCA_MEM_SHRINK_OUT_FREE_KEY,

	HNS_IB_ATTR_DCA_MEM_SHRINK_OUT_FREE_MEMS,

};



#endif /* HNS_ABI_USER_H */