[dpdk-dev] [PATCH v4 03/25] common/mlx5: share the mlx5 glue reference

[Matan Azrad <matan@mellanox.com>]

A new Mellanox vdpa PMD will be added to support vdpa operations by
Mellanox adapters.

Both, the mlx5 PMD and the vdpa mlx5 PMD should initialize the glue.

The glue initialization should be only one per process, so all the mlx5
PMDs using the glue should share the same glue object.

Move the glue initialization to be in common/mlx5 library to be
initialized by its constructor only once.

Signed-off-by: Matan Azrad <matan@mellanox.com>
Acked-by: Viacheslav Ovsiienko <viacheslavo@mellanox.com>
---
 drivers/common/mlx5/mlx5_common.c | 173 +++++++++++++++++++++++++++++++++++++-
 drivers/net/mlx5/Makefile         |   9 --
 drivers/net/mlx5/meson.build      |   4 -
 drivers/net/mlx5/mlx5.c           | 172 +------------------------------------
 4 files changed, 173 insertions(+), 185 deletions(-)

diff --git a/drivers/common/mlx5/mlx5_common.c b/drivers/common/mlx5/mlx5_common.c
index 14ebd30..9c88a63 100644
--- a/drivers/common/mlx5/mlx5_common.c
+++ b/drivers/common/mlx5/mlx5_common.c
@@ -2,16 +2,185 @@
  * Copyright 2019 Mellanox Technologies, Ltd
  */
 
+#include <dlfcn.h>
+#include <unistd.h>
+#include <string.h>
+
+#include <rte_errno.h>
+
 #include "mlx5_common.h"
+#include "mlx5_common_utils.h"
+#include "mlx5_glue.h"
 
 
 int mlx5_common_logtype;
 
 
-RTE_INIT(rte_mlx5_common_pmd_init)
+#ifdef RTE_IBVERBS_LINK_DLOPEN
+
+/**
+ * Suffix RTE_EAL_PMD_PATH with "-glue".
+ *
+ * This function performs a sanity check on RTE_EAL_PMD_PATH before
+ * suffixing its last component.
+ *
+ * @param buf[out]
+ *   Output buffer, should be large enough otherwise NULL is returned.
+ * @param size
+ *   Size of @p out.
+ *
+ * @return
+ *   Pointer to @p buf or @p NULL in case suffix cannot be appended.
+ */
+static char *
+mlx5_glue_path(char *buf, size_t size)
+{
+	static const char *const bad[] = { "/", ".", "..", NULL };
+	const char *path = RTE_EAL_PMD_PATH;
+	size_t len = strlen(path);
+	size_t off;
+	int i;
+
+	while (len && path[len - 1] == '/')
+		--len;
+	for (off = len; off && path[off - 1] != '/'; --off)
+		;
+	for (i = 0; bad[i]; ++i)
+		if (!strncmp(path + off, bad[i], (int)(len - off)))
+			goto error;
+	i = snprintf(buf, size, "%.*s-glue", (int)len, path);
+	if (i == -1 || (size_t)i >= size)
+		goto error;
+	return buf;
+error:
+	RTE_LOG(ERR, PMD, "unable to append \"-glue\" to last component of"
+		" RTE_EAL_PMD_PATH (\"" RTE_EAL_PMD_PATH "\"), please"
+		" re-configure DPDK");
+	return NULL;
+}
+#endif
+
+/**
+ * Initialization routine for run-time dependency on rdma-core.
+ */
+RTE_INIT_PRIO(mlx5_glue_init, CLASS)
 {
-	/* Initialize driver log type. */
+	void *handle = NULL;
+
+	/* Initialize common log type. */
 	mlx5_common_logtype = rte_log_register("pmd.common.mlx5");
 	if (mlx5_common_logtype >= 0)
 		rte_log_set_level(mlx5_common_logtype, RTE_LOG_NOTICE);
+	/*
+	 * RDMAV_HUGEPAGES_SAFE tells ibv_fork_init() we intend to use
+	 * huge pages. Calling ibv_fork_init() during init allows
+	 * applications to use fork() safely for purposes other than
+	 * using this PMD, which is not supported in forked processes.
+	 */
+	setenv("RDMAV_HUGEPAGES_SAFE", "1", 1);
+	/* Match the size of Rx completion entry to the size of a cacheline. */
+	if (RTE_CACHE_LINE_SIZE == 128)
+		setenv("MLX5_CQE_SIZE", "128", 0);
+	/*
+	 * MLX5_DEVICE_FATAL_CLEANUP tells ibv_destroy functions to
+	 * cleanup all the Verbs resources even when the device was removed.
+	 */
+	setenv("MLX5_DEVICE_FATAL_CLEANUP", "1", 1);
+	/* The glue initialization was done earlier by mlx5 common library. */
+#ifdef RTE_IBVERBS_LINK_DLOPEN
+	char glue_path[sizeof(RTE_EAL_PMD_PATH) - 1 + sizeof("-glue")];
+	const char *path[] = {
+		/*
+		 * A basic security check is necessary before trusting
+		 * MLX5_GLUE_PATH, which may override RTE_EAL_PMD_PATH.
+		 */
+		(geteuid() == getuid() && getegid() == getgid() ?
+		 getenv("MLX5_GLUE_PATH") : NULL),
+		/*
+		 * When RTE_EAL_PMD_PATH is set, use its glue-suffixed
+		 * variant, otherwise let dlopen() look up libraries on its
+		 * own.
+		 */
+		(*RTE_EAL_PMD_PATH ?
+		 mlx5_glue_path(glue_path, sizeof(glue_path)) : ""),
+	};
+	unsigned int i = 0;
+	void **sym;
+	const char *dlmsg;
+
+	while (!handle && i != RTE_DIM(path)) {
+		const char *end;
+		size_t len;
+		int ret;
+
+		if (!path[i]) {
+			++i;
+			continue;
+		}
+		end = strpbrk(path[i], ":;");
+		if (!end)
+			end = path[i] + strlen(path[i]);
+		len = end - path[i];
+		ret = 0;
+		do {
+			char name[ret + 1];
+
+			ret = snprintf(name, sizeof(name), "%.*s%s" MLX5_GLUE,
+				       (int)len, path[i],
+				       (!len || *(end - 1) == '/') ? "" : "/");
+			if (ret == -1)
+				break;
+			if (sizeof(name) != (size_t)ret + 1)
+				continue;
+			DRV_LOG(DEBUG, "Looking for rdma-core glue as "
+				"\"%s\"", name);
+			handle = dlopen(name, RTLD_LAZY);
+			break;
+		} while (1);
+		path[i] = end + 1;
+		if (!*end)
+			++i;
+	}
+	if (!handle) {
+		rte_errno = EINVAL;
+		dlmsg = dlerror();
+		if (dlmsg)
+			DRV_LOG(WARNING, "Cannot load glue library: %s", dlmsg);
+		goto glue_error;
+	}
+	sym = dlsym(handle, "mlx5_glue");
+	if (!sym || !*sym) {
+		rte_errno = EINVAL;
+		dlmsg = dlerror();
+		if (dlmsg)
+			DRV_LOG(ERR, "Cannot resolve glue symbol: %s", dlmsg);
+		goto glue_error;
+	}
+	mlx5_glue = *sym;
+#endif /* RTE_IBVERBS_LINK_DLOPEN */
+#ifndef NDEBUG
+	/* Glue structure must not contain any NULL pointers. */
+	{
+		unsigned int i;
+
+		for (i = 0; i != sizeof(*mlx5_glue) / sizeof(void *); ++i)
+			assert(((const void *const *)mlx5_glue)[i]);
+	}
+#endif
+	if (strcmp(mlx5_glue->version, MLX5_GLUE_VERSION)) {
+		rte_errno = EINVAL;
+		DRV_LOG(ERR, "rdma-core glue \"%s\" mismatch: \"%s\" is "
+			"required", mlx5_glue->version, MLX5_GLUE_VERSION);
+		goto glue_error;
+	}
+	mlx5_glue->fork_init();
+	return;
+glue_error:
+	if (handle)
+		dlclose(handle);
+	DRV_LOG(WARNING, "Cannot initialize MLX5 common due to missing"
+		" run-time dependency on rdma-core libraries (libibverbs,"
+		" libmlx5)");
+	mlx5_glue = NULL;
+	return;
 }
diff --git a/drivers/net/mlx5/Makefile b/drivers/net/mlx5/Makefile
index a9558ca..dc6b3c8 100644
--- a/drivers/net/mlx5/Makefile
+++ b/drivers/net/mlx5/Makefile
@@ -6,15 +6,6 @@ include $(RTE_SDK)/mk/rte.vars.mk
 
 # Library name.
 LIB = librte_pmd_mlx5.a
-LIB_GLUE = $(LIB_GLUE_BASE).$(LIB_GLUE_VERSION)
-LIB_GLUE_BASE = librte_pmd_mlx5_glue.so
-LIB_GLUE_VERSION = 20.02.0
-
-ifeq ($(CONFIG_RTE_IBVERBS_LINK_DLOPEN),y)
-CFLAGS += -DMLX5_GLUE='"$(LIB_GLUE)"'
-CFLAGS += -DMLX5_GLUE_VERSION='"$(LIB_GLUE_VERSION)"'
-LDLIBS += -ldl
-endif
 
 # Sources.
 SRCS-$(CONFIG_RTE_LIBRTE_MLX5_PMD) += mlx5.c
diff --git a/drivers/net/mlx5/meson.build b/drivers/net/mlx5/meson.build
index f6d0db9..e10ef3a 100644
--- a/drivers/net/mlx5/meson.build
+++ b/drivers/net/mlx5/meson.build
@@ -8,10 +8,6 @@ if not is_linux
 	subdir_done()
 endif
 
-LIB_GLUE_BASE = 'librte_pmd_mlx5_glue.so'
-LIB_GLUE_VERSION = '20.02.0'
-LIB_GLUE = LIB_GLUE_BASE + '.' + LIB_GLUE_VERSION
-
 allow_experimental_apis = true
 deps += ['hash', 'common_mlx5']
 sources = files(
diff --git a/drivers/net/mlx5/mlx5.c b/drivers/net/mlx5/mlx5.c
index 7cf357d..8fbe826 100644
--- a/drivers/net/mlx5/mlx5.c
+++ b/drivers/net/mlx5/mlx5.c
@@ -7,7 +7,6 @@
 #include <unistd.h>
 #include <string.h>
 #include <assert.h>
-#include <dlfcn.h>
 #include <stdint.h>
 #include <stdlib.h>
 #include <errno.h>
@@ -3505,138 +3504,6 @@ struct mlx5_flow_id_pool *
 		     RTE_PCI_DRV_PROBE_AGAIN,
 };
 
-#ifdef RTE_IBVERBS_LINK_DLOPEN
-
-/**
- * Suffix RTE_EAL_PMD_PATH with "-glue".
- *
- * This function performs a sanity check on RTE_EAL_PMD_PATH before
- * suffixing its last component.
- *
- * @param buf[out]
- *   Output buffer, should be large enough otherwise NULL is returned.
- * @param size
- *   Size of @p out.
- *
- * @return
- *   Pointer to @p buf or @p NULL in case suffix cannot be appended.
- */
-static char *
-mlx5_glue_path(char *buf, size_t size)
-{
-	static const char *const bad[] = { "/", ".", "..", NULL };
-	const char *path = RTE_EAL_PMD_PATH;
-	size_t len = strlen(path);
-	size_t off;
-	int i;
-
-	while (len && path[len - 1] == '/')
-		--len;
-	for (off = len; off && path[off - 1] != '/'; --off)
-		;
-	for (i = 0; bad[i]; ++i)
-		if (!strncmp(path + off, bad[i], (int)(len - off)))
-			goto error;
-	i = snprintf(buf, size, "%.*s-glue", (int)len, path);
-	if (i == -1 || (size_t)i >= size)
-		goto error;
-	return buf;
-error:
-	DRV_LOG(ERR,
-		"unable to append \"-glue\" to last component of"
-		" RTE_EAL_PMD_PATH (\"" RTE_EAL_PMD_PATH "\"),"
-		" please re-configure DPDK");
-	return NULL;
-}
-
-/**
- * Initialization routine for run-time dependency on rdma-core.
- */
-static int
-mlx5_glue_init(void)
-{
-	char glue_path[sizeof(RTE_EAL_PMD_PATH) - 1 + sizeof("-glue")];
-	const char *path[] = {
-		/*
-		 * A basic security check is necessary before trusting
-		 * MLX5_GLUE_PATH, which may override RTE_EAL_PMD_PATH.
-		 */
-		(geteuid() == getuid() && getegid() == getgid() ?
-		 getenv("MLX5_GLUE_PATH") : NULL),
-		/*
-		 * When RTE_EAL_PMD_PATH is set, use its glue-suffixed
-		 * variant, otherwise let dlopen() look up libraries on its
-		 * own.
-		 */
-		(*RTE_EAL_PMD_PATH ?
-		 mlx5_glue_path(glue_path, sizeof(glue_path)) : ""),
-	};
-	unsigned int i = 0;
-	void *handle = NULL;
-	void **sym;
-	const char *dlmsg;
-
-	while (!handle && i != RTE_DIM(path)) {
-		const char *end;
-		size_t len;
-		int ret;
-
-		if (!path[i]) {
-			++i;
-			continue;
-		}
-		end = strpbrk(path[i], ":;");
-		if (!end)
-			end = path[i] + strlen(path[i]);
-		len = end - path[i];
-		ret = 0;
-		do {
-			char name[ret + 1];
-
-			ret = snprintf(name, sizeof(name), "%.*s%s" MLX5_GLUE,
-				       (int)len, path[i],
-				       (!len || *(end - 1) == '/') ? "" : "/");
-			if (ret == -1)
-				break;
-			if (sizeof(name) != (size_t)ret + 1)
-				continue;
-			DRV_LOG(DEBUG, "looking for rdma-core glue as \"%s\"",
-				name);
-			handle = dlopen(name, RTLD_LAZY);
-			break;
-		} while (1);
-		path[i] = end + 1;
-		if (!*end)
-			++i;
-	}
-	if (!handle) {
-		rte_errno = EINVAL;
-		dlmsg = dlerror();
-		if (dlmsg)
-			DRV_LOG(WARNING, "cannot load glue library: %s", dlmsg);
-		goto glue_error;
-	}
-	sym = dlsym(handle, "mlx5_glue");
-	if (!sym || !*sym) {
-		rte_errno = EINVAL;
-		dlmsg = dlerror();
-		if (dlmsg)
-			DRV_LOG(ERR, "cannot resolve glue symbol: %s", dlmsg);
-		goto glue_error;
-	}
-	mlx5_glue = *sym;
-	return 0;
-glue_error:
-	if (handle)
-		dlclose(handle);
-	DRV_LOG(WARNING,
-		"cannot initialize PMD due to missing run-time dependency on"
-		" rdma-core libraries (libibverbs, libmlx5)");
-	return -rte_errno;
-}
-
-#endif
-
 /**
  * Driver initialization routine.
  */
@@ -3651,43 +3518,8 @@ struct mlx5_flow_id_pool *
 	mlx5_set_ptype_table();
 	mlx5_set_cksum_table();
 	mlx5_set_swp_types_table();
-	/*
-	 * RDMAV_HUGEPAGES_SAFE tells ibv_fork_init() we intend to use
-	 * huge pages. Calling ibv_fork_init() during init allows
-	 * applications to use fork() safely for purposes other than
-	 * using this PMD, which is not supported in forked processes.
-	 */
-	setenv("RDMAV_HUGEPAGES_SAFE", "1", 1);
-	/* Match the size of Rx completion entry to the size of a cacheline. */
-	if (RTE_CACHE_LINE_SIZE == 128)
-		setenv("MLX5_CQE_SIZE", "128", 0);
-	/*
-	 * MLX5_DEVICE_FATAL_CLEANUP tells ibv_destroy functions to
-	 * cleanup all the Verbs resources even when the device was removed.
-	 */
-	setenv("MLX5_DEVICE_FATAL_CLEANUP", "1", 1);
-#ifdef RTE_IBVERBS_LINK_DLOPEN
-	if (mlx5_glue_init())
-		return;
-	assert(mlx5_glue);
-#endif
-#ifndef NDEBUG
-	/* Glue structure must not contain any NULL pointers. */
-	{
-		unsigned int i;
-
-		for (i = 0; i != sizeof(*mlx5_glue) / sizeof(void *); ++i)
-			assert(((const void *const *)mlx5_glue)[i]);
-	}
-#endif
-	if (strcmp(mlx5_glue->version, MLX5_GLUE_VERSION)) {
-		DRV_LOG(ERR,
-			"rdma-core glue \"%s\" mismatch: \"%s\" is required",
-			mlx5_glue->version, MLX5_GLUE_VERSION);
-		return;
-	}
-	mlx5_glue->fork_init();
-	rte_pci_register(&mlx5_driver);
+	if (mlx5_glue)
+		rte_pci_register(&mlx5_driver);
 }
 
 RTE_PMD_EXPORT_NAME(net_mlx5, __COUNTER__);
-- 
1.8.3.1