Merge pull request ofiwg#5916 from rwespetal/efa-reuse-pd

prov/efa: reuse protection domain in same process address space

prov/efa/src/efa.h

@@ -194,13 +194,19 @@ struct efa_cq {
 
 struct efa_context {
 	struct ibv_context	*ibv_ctx;
+	int			dev_idx;
 	uint64_t		max_mr_size;
 	uint16_t		inline_buf_size;
 	uint16_t		max_wr_rdma_sge;
 	uint32_t		max_rdma_size;
 	uint32_t		device_caps;
 };
 
+struct efa_pd {
+	struct ibv_pd	   *ibv_pd;
+	int		   use_cnt;
+};
+
 struct efa_qp {
 	struct ibv_qp	*ibv_qp;
 	struct ibv_qp_ex *ibv_qp_ex;
@@ -334,6 +340,10 @@ extern struct fi_ops_cm efa_ep_cm_ops;
 extern struct fi_ops_msg efa_ep_msg_ops;
 extern struct fi_ops_rma efa_ep_rma_ops;
 
+extern fastlock_t pd_list_lock;
+// This list has the same indicies as ctx_list.
+extern struct efa_pd *pd_list;
+
 int efa_device_init(void);
 void efa_device_free(void);
 

prov/efa/src/efa_device.c

@@ -87,6 +87,8 @@ int efa_device_init(void)
 	int ctx_idx;
 	int ret;
 
+	fastlock_init(&pd_list_lock);
+
 	device_list = ibv_get_device_list(&dev_cnt);
 	if (dev_cnt <= 0)
 		return -ENODEV;
@@ -97,12 +99,19 @@ int efa_device_init(void)
 		goto err_free_dev_list;
 	}
 
+	pd_list = calloc(dev_cnt, sizeof(*pd_list));
+	if (!pd_list) {
+		ret = -ENOMEM;
+		goto err_free_ctx_list;
+	}
+
 	for (ctx_idx = 0; ctx_idx < dev_cnt; ctx_idx++) {
 		ctx_list[ctx_idx] = efa_device_open(device_list[ctx_idx]);
 		if (!ctx_list[ctx_idx]) {
 			ret = -ENODEV;
 			goto err_close_devs;
 		}
+		ctx_list[ctx_idx]->dev_idx = ctx_idx;
 	}
 
 	ibv_free_device_list(device_list);
@@ -112,6 +121,8 @@ int efa_device_init(void)
 err_close_devs:
 	for (ctx_idx--; ctx_idx >= 0; ctx_idx--)
 		efa_device_close(ctx_list[ctx_idx]);
+	free(pd_list);
+err_free_ctx_list:
 	free(ctx_list);
 err_free_dev_list:
 	ibv_free_device_list(device_list);
@@ -123,11 +134,15 @@ void efa_device_free(void)
 {
 	int i;
 
-	for (i = 0; i < dev_cnt; i++)
+	for (i = 0; i < dev_cnt; i++) {
+		assert(pd_list[i].use_cnt == 0);
 		efa_device_close(ctx_list[i]);
+	}
 
+	free(pd_list);
 	free(ctx_list);
 	dev_cnt = 0;
+	fastlock_destroy(&pd_list_lock);
 }
 
 struct efa_context **efa_device_get_context_list(int *num_ctx)

prov/efa/src/efa_domain.c

@@ -37,9 +37,13 @@
 #include "efa.h"
 #include "rxr_cntr.h"
 
+fastlock_t pd_list_lock;
+struct efa_pd *pd_list = NULL;
+
 static int efa_domain_close(fid_t fid)
 {
 	struct efa_domain *domain;
+	struct efa_pd *efa_pd;
 	int ret;
 
 	domain = container_of(fid, struct efa_domain,
@@ -49,12 +53,21 @@ static int efa_domain_close(fid_t fid)
 		ofi_mr_cache_cleanup(&domain->cache);
 
 	if (domain->ibv_pd) {
-		ret = -ibv_dealloc_pd(domain->ibv_pd);
-		if (ret) {
-			EFA_INFO_ERRNO(FI_LOG_DOMAIN, "ibv_dealloc_pd", ret);
-			return ret;
+		fastlock_acquire(&pd_list_lock);
+		efa_pd = &pd_list[domain->ctx->dev_idx];
+		if (efa_pd->use_cnt == 1) {
+			ret = -ibv_dealloc_pd(domain->ibv_pd);
+			if (ret) {
+				fastlock_release(&pd_list_lock);
+				EFA_INFO_ERRNO(FI_LOG_DOMAIN, "ibv_dealloc_pd",
+				               ret);
+				return ret;
+			}
+			efa_pd->ibv_pd = NULL;
 		}
+		efa_pd->use_cnt--;
 		domain->ibv_pd = NULL;
+		fastlock_release(&pd_list_lock);
 	}
 
 	ret = ofi_domain_close(&domain->util_domain);
@@ -94,6 +107,25 @@ static int efa_open_device_by_name(struct efa_domain *domain, const char *name)
 		}
 	}
 
+	/*
+	 * Check if a PD has already been allocated for this device and reuse
+	 * it if this is the case.
+	 */
+	fastlock_acquire(&pd_list_lock);
+	if (pd_list[i].ibv_pd) {
+		domain->ibv_pd = pd_list[i].ibv_pd;
+		pd_list[i].use_cnt++;
+	} else {
+		domain->ibv_pd = ibv_alloc_pd(domain->ctx->ibv_ctx);
+		if (!domain->ibv_pd) {
+			ret = -errno;
+		} else {
+			pd_list[i].ibv_pd = domain->ibv_pd;
+			pd_list[i].use_cnt++;
+		}
+	}
+	fastlock_release(&pd_list_lock);
+
 	efa_device_free_context_list(ctx_list);
 	return ret;
 }
@@ -172,12 +204,6 @@ int efa_domain_open(struct fid_fabric *fabric_fid, struct fi_info *info,
 	if (ret)
 		goto err_free_info;
 
-	domain->ibv_pd = ibv_alloc_pd(domain->ctx->ibv_ctx);
-	if (!domain->ibv_pd) {
-		ret = -errno;
-		goto err_free_info;
-	}
-
 	domain->util_domain.domain_fid.fid.ops = &efa_fid_ops;
 	domain->util_domain.domain_fid.ops = &efa_domain_ops;
 	/* RMA mr_modes are being removed, since EFA layer