[dpdk-dev] [PATCH v3] eal: add function to return number of detected sockets

[Anatoly Burakov]

During lcore scan, find maximum socket ID and store it.

Signed-off-by: Anatoly Burakov <anatoly.burakov at intel.com>
---

Notes:
    v3:
    - Added ABI backwards compatibility
    
    v2:
    - checkpatch changes
    - check socket before deciding if the core is not to be used

 lib/librte_eal/common/eal_common_lcore.c  | 37 +++++++++++++++++++++----------
 lib/librte_eal/common/include/rte_eal.h   | 25 +++++++++++++++++++++
 lib/librte_eal/common/include/rte_lcore.h |  8 +++++++
 lib/librte_eal/linuxapp/eal/eal.c         | 27 +++++++++++++++++++++-
 lib/librte_eal/rte_eal_version.map        |  9 +++++++-
 5 files changed, 92 insertions(+), 14 deletions(-)

diff --git a/lib/librte_eal/common/eal_common_lcore.c b/lib/librte_eal/common/eal_common_lcore.c
index 7724fa4..827ddeb 100644
--- a/lib/librte_eal/common/eal_common_lcore.c
+++ b/lib/librte_eal/common/eal_common_lcore.c
@@ -28,6 +28,7 @@ rte_eal_cpu_init(void)
 	struct rte_config *config = rte_eal_get_configuration();
 	unsigned lcore_id;
 	unsigned count = 0;
+	unsigned int socket_id, max_socket_id = 0;
 
 	/*
 	 * Parse the maximum set of logical cores, detect the subset of running
@@ -39,6 +40,19 @@ rte_eal_cpu_init(void)
 		/* init cpuset for per lcore config */
 		CPU_ZERO(&lcore_config[lcore_id].cpuset);
 
+		/* find socket first */
+		socket_id = eal_cpu_socket_id(lcore_id);
+		if (socket_id >= RTE_MAX_NUMA_NODES) {
+#ifdef RTE_EAL_ALLOW_INV_SOCKET_ID
+			socket_id = 0;
+#else
+			RTE_LOG(ERR, EAL, "Socket ID (%u) is greater than RTE_MAX_NUMA_NODES (%d)\n",
+					socket_id, RTE_MAX_NUMA_NODES);
+			return -1;
+#endif
+		}
+		max_socket_id = RTE_MAX(max_socket_id, socket_id);
+
 		/* in 1:1 mapping, record related cpu detected state */
 		lcore_config[lcore_id].detected = eal_cpu_detected(lcore_id);
 		if (lcore_config[lcore_id].detected == 0) {
@@ -54,18 +68,7 @@ rte_eal_cpu_init(void)
 		config->lcore_role[lcore_id] = ROLE_RTE;
 		lcore_config[lcore_id].core_role = ROLE_RTE;
 		lcore_config[lcore_id].core_id = eal_cpu_core_id(lcore_id);
-		lcore_config[lcore_id].socket_id = eal_cpu_socket_id(lcore_id);
-		if (lcore_config[lcore_id].socket_id >= RTE_MAX_NUMA_NODES) {
-#ifdef RTE_EAL_ALLOW_INV_SOCKET_ID
-			lcore_config[lcore_id].socket_id = 0;
-#else
-			RTE_LOG(ERR, EAL, "Socket ID (%u) is greater than "
-				"RTE_MAX_NUMA_NODES (%d)\n",
-				lcore_config[lcore_id].socket_id,
-				RTE_MAX_NUMA_NODES);
-			return -1;
-#endif
-		}
+		lcore_config[lcore_id].socket_id = socket_id;
 		RTE_LOG(DEBUG, EAL, "Detected lcore %u as "
 				"core %u on socket %u\n",
 				lcore_id, lcore_config[lcore_id].core_id,
@@ -79,5 +82,15 @@ rte_eal_cpu_init(void)
 		RTE_MAX_LCORE);
 	RTE_LOG(INFO, EAL, "Detected %u lcore(s)\n", config->lcore_count);
 
+	config->numa_node_count = max_socket_id + 1;
+	RTE_LOG(INFO, EAL, "Detected %u NUMA nodes\n", config->numa_node_count);
+
 	return 0;
 }
+
+unsigned int
+rte_num_sockets(void)
+{
+	const struct rte_config *config = rte_eal_get_configuration();
+	return config->numa_node_count;
+}
diff --git a/lib/librte_eal/common/include/rte_eal.h b/lib/librte_eal/common/include/rte_eal.h
index 08c6637..bbf54e2 100644
--- a/lib/librte_eal/common/include/rte_eal.h
+++ b/lib/librte_eal/common/include/rte_eal.h
@@ -57,6 +57,29 @@ enum rte_proc_type_t {
 struct rte_config {
 	uint32_t master_lcore;       /**< Id of the master lcore */
 	uint32_t lcore_count;        /**< Number of available logical cores. */
+	uint32_t numa_node_count;    /**< Number of detected NUMA nodes. */
+	uint32_t service_lcore_count;/**< Number of available service cores. */
+	enum rte_lcore_role_t lcore_role[RTE_MAX_LCORE]; /**< State of cores. */
+
+	/** Primary or secondary configuration */
+	enum rte_proc_type_t process_type;
+
+	/** PA or VA mapping mode */
+	enum rte_iova_mode iova_mode;
+
+	/**
+	 * Pointer to memory configuration, which may be shared across multiple
+	 * DPDK instances
+	 */
+	struct rte_mem_config *mem_config;
+} __attribute__((__packed__));
+
+/**
+ * The global RTE configuration structure - 18.02 ABI version.
+ */
+struct rte_config_v1802 {
+	uint32_t master_lcore;       /**< Id of the master lcore */
+	uint32_t lcore_count;        /**< Number of available logical cores. */
 	uint32_t service_lcore_count;/**< Number of available service cores. */
 	enum rte_lcore_role_t lcore_role[RTE_MAX_LCORE]; /**< State of cores. */
 
@@ -80,6 +103,8 @@ struct rte_config {
  *   A pointer to the global configuration structure.
  */
 struct rte_config *rte_eal_get_configuration(void);
+struct rte_config_v1802 *rte_eal_get_configuration_v1802(void);
+struct rte_config *rte_eal_get_configuration_v1805(void);
 
 /**
  * Get a lcore's role.
diff --git a/lib/librte_eal/common/include/rte_lcore.h b/lib/librte_eal/common/include/rte_lcore.h
index d84bcff..ddf4c64 100644
--- a/lib/librte_eal/common/include/rte_lcore.h
+++ b/lib/librte_eal/common/include/rte_lcore.h
@@ -120,6 +120,14 @@ rte_lcore_index(int lcore_id)
 unsigned rte_socket_id(void);
 
 /**
+ * Return number of physical sockets on the system.
+ * @return
+ *   the number of physical sockets as recognized by EAL
+ *
+ */
+unsigned int rte_num_sockets(void);
+
+/**
  * Get the ID of the physical socket of the specified lcore
  *
  * @param lcore_id
diff --git a/lib/librte_eal/linuxapp/eal/eal.c b/lib/librte_eal/linuxapp/eal/eal.c
index 451fdaf..757f404 100644
--- a/lib/librte_eal/linuxapp/eal/eal.c
+++ b/lib/librte_eal/linuxapp/eal/eal.c
@@ -67,6 +67,9 @@ static rte_usage_hook_t	rte_application_usage_hook = NULL;
 /* early configuration structure, when memory config is not mmapped */
 static struct rte_mem_config early_mem_config;
 
+/* compatibility structure to return to old ABI calls */
+static struct rte_config_v1802 v1802_config;
+
 /* define fd variable here, because file needs to be kept open for the
  * duration of the program, as we hold a write lock on it in the primary proc */
 static int mem_cfg_fd = -1;
@@ -103,11 +106,33 @@ rte_eal_mbuf_default_mempool_ops(void)
 }
 
 /* Return a pointer to the configuration structure */
+struct rte_config_v1802 *
+rte_eal_get_configuration_v1802(void)
+{
+	/* copy everything to old config so that it's up to date */
+	v1802_config.iova_mode = rte_config.iova_mode;
+	v1802_config.lcore_count = rte_config.lcore_count;
+	memcpy(v1802_config.lcore_role, rte_config.lcore_role,
+			sizeof(rte_config.lcore_role));
+	v1802_config.master_lcore = rte_config.master_lcore;
+	v1802_config.mem_config = rte_config.mem_config;
+	v1802_config.process_type = rte_config.process_type;
+	v1802_config.service_lcore_count = rte_config.service_lcore_count;
+
+	return &v1802_config;
+}
+VERSION_SYMBOL(rte_eal_get_configuration, _v1802, 18.02);
+
+/* Return a pointer to the configuration structure */
 struct rte_config *
-rte_eal_get_configuration(void)
+rte_eal_get_configuration_v1805(void)
 {
 	return &rte_config;
 }
+VERSION_SYMBOL(rte_eal_get_configuration, _v1805, 18.05);
+BIND_DEFAULT_SYMBOL(rte_eal_get_configuration, _v1805, 18.05);
+MAP_STATIC_SYMBOL(struct rte_config *rte_eal_get_configuration(void),
+		rte_eal_get_configuration_v1805);
 
 enum rte_iova_mode
 rte_eal_iova_mode(void)
diff --git a/lib/librte_eal/rte_eal_version.map b/lib/librte_eal/rte_eal_version.map
index 4146907..fc83e74 100644
--- a/lib/librte_eal/rte_eal_version.map
+++ b/lib/librte_eal/rte_eal_version.map
@@ -211,6 +211,13 @@ DPDK_18.02 {
 
 }  DPDK_17.11;
 
+DPDK_18.05 {
+	global:
+
+	rte_num_sockets;
+
+} DPDK_18.02;
+
 EXPERIMENTAL {
 	global:
 
@@ -255,4 +262,4 @@ EXPERIMENTAL {
 	rte_service_set_stats_enable;
 	rte_service_start_with_defaults;
 
-} DPDK_18.02;
+} DPDK_18.05;
-- 
2.7.4