eal: add option register infrastructure

This commit adds infrastructure to EAL that allows an application to
register it's init function with EAL. This allows libraries to be
initialized at the end of EAL init.

This infrastructure allows libraries that depend on EAL to be initialized
as part of EAL init, removing circular dependency issues.

Signed-off-by: Kevin Laatz <kevin.laatz@intel.com>
Acked-by: Harry van Haaren <harry.van.haaren@intel.com>
Acked-by: Gaetan Rivet <gaetan.rivet@6wind.com>

diff --git a/lib/librte_eal/bsdapp/eal/Makefile b/lib/librte_eal/bsdapp/eal/Makefile
index d19f53c1e3aa6601077c8c08a37e33cbf4221d6b..bfeddaadcf676dfee2d5274268f9b8748262b9f2 100644 (file)
--- a/lib/librte_eal/bsdapp/eal/Makefile
+++ b/lib/librte_eal/bsdapp/eal/Makefile
@@ -67,6 +67,7 @@ SRCS-$(CONFIG_RTE_EXEC_ENV_BSDAPP) += malloc_elem.c
 SRCS-$(CONFIG_RTE_EXEC_ENV_BSDAPP) += malloc_heap.c
 SRCS-$(CONFIG_RTE_EXEC_ENV_BSDAPP) += malloc_mp.c
 SRCS-$(CONFIG_RTE_EXEC_ENV_BSDAPP) += rte_keepalive.c
+SRCS-$(CONFIG_RTE_EXEC_ENV_BSDAPP) += rte_option.c
 SRCS-$(CONFIG_RTE_EXEC_ENV_BSDAPP) += rte_service.c
 SRCS-$(CONFIG_RTE_EXEC_ENV_BSDAPP) += rte_reciprocal.c
 

diff --git a/lib/librte_eal/bsdapp/eal/eal.c b/lib/librte_eal/bsdapp/eal/eal.c
index f94c5c5f4c589f969d605215104bc3e33c1ca8fb..11cbda964559dc77a02aa708b0b3743f510e8cea 100644 (file)
--- a/lib/librte_eal/bsdapp/eal/eal.c
+++ b/lib/librte_eal/bsdapp/eal/eal.c
@@ -42,6 +42,7 @@
 #include <rte_devargs.h>
 #include <rte_version.h>
 #include <rte_vfio.h>
+#include <rte_option.h>
 #include <rte_atomic.h>
 #include <malloc_heap.h>
 
@@ -414,12 +415,20 @@ eal_parse_args(int argc, char **argv)
        argvopt = argv;
        optind = 1;
        optreset = 1;
+       opterr = 0;
 
        while ((opt = getopt_long(argc, argvopt, eal_short_options,
                                  eal_long_options, &option_index)) != EOF) {
 
-               /* getopt is not happy, stop right now */
+               /*
+                * getopt didn't recognise the option, lets parse the
+                * registered options to see if the flag is valid
+                */
                if (opt == '?') {
+                       ret = rte_option_parse(argv[optind-1]);
+                       if (ret == 0)
+                               continue;
+
                        eal_usage(prgname);
                        ret = -1;
                        goto out;
@@ -791,6 +800,9 @@ rte_eal_init(int argc, char **argv)
 
        rte_eal_mcfg_complete();
 
+       /* Call each registered callback, if enabled */
+       rte_option_init();
+
        return fctret;
 }
 

diff --git a/lib/librte_eal/common/Makefile b/lib/librte_eal/common/Makefile
index cca68826f6ef86418bcaaa51cdf4dd4a408208c2..87d8c455dd48950869dd45eea06365710d45a52d 100644 (file)
--- a/lib/librte_eal/common/Makefile
+++ b/lib/librte_eal/common/Makefile
@@ -12,6 +12,7 @@ INC += rte_tailq.h rte_interrupts.h rte_alarm.h
 INC += rte_string_fns.h rte_version.h
 INC += rte_eal_memconfig.h rte_malloc_heap.h
 INC += rte_hexdump.h rte_devargs.h rte_bus.h rte_dev.h rte_class.h
+INC += rte_option.h
 INC += rte_pci_dev_feature_defs.h rte_pci_dev_features.h
 INC += rte_malloc.h rte_keepalive.h rte_time.h
 INC += rte_service.h rte_service_component.h

diff --git a/lib/librte_eal/common/eal_private.h b/lib/librte_eal/common/eal_private.h
index b189d675dc128dedc0098d38c000b54bf75de84c..442c6dc487896427113f1f80269712795af56131 100644 (file)
--- a/lib/librte_eal/common/eal_private.h
+++ b/lib/librte_eal/common/eal_private.h
@@ -349,4 +349,25 @@ dev_sigbus_handler_register(void);
 int
 dev_sigbus_handler_unregister(void);
 
+/**
+ * Check if the option is registered.
+ *
+ * @param option
+ *  The option to be parsed.
+ *
+ * @return
+ *  0 on success
+ * @return
+ *  -1 on fail
+ */
+int
+rte_option_parse(const char *opt);
+
+/**
+ * Iterate through the registered options and execute the associated
+ * callback if enabled.
+ */
+void
+rte_option_init(void);
+
 #endif /* _EAL_PRIVATE_H_ */

diff --git a/lib/librte_eal/common/include/rte_option.h b/lib/librte_eal/common/include/rte_option.h
new file mode 100644 (file)
index 0000000..8957b97
--- /dev/null
+++ b/lib/librte_eal/common/include/rte_option.h
@@ -0,0 +1,63 @@
+/* SPDX-License-Identifier: BSD-3-Clause
+ * Copyright(c) 2018 Intel Corporation.
+ */
+
+#ifndef __INCLUDE_RTE_OPTION_H__
+#define __INCLUDE_RTE_OPTION_H__
+
+/**
+ * @file
+ *
+ * This API offers the ability to register options to the EAL command line and
+ * map those options to functions that will be executed at the end of EAL
+ * initialization. These options will be available as part of the EAL command
+ * line of applications and are dynamically managed.
+ *
+ * This is used primarily by DPDK libraries offering command line options.
+ * Currently, this API is limited to registering options without argument.
+ *
+ * The register API can be used to resolve circular dependency issues
+ * between EAL and the library. The library uses EAL, but is also initialized
+ * by EAL. Hence, EAL depends on the init function of the library. The API
+ * introduced in rte_option allows us to register the library init with EAL
+ * (passing a function pointer) and avoid the circular dependency.
+ */
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+typedef int (*rte_option_cb)(void);
+
+/*
+ * Structure describing the EAL command line option being registered.
+ */
+struct rte_option {
+       TAILQ_ENTRY(rte_option) next; /**< Next entry in the list. */
+       char *opt_str;             /**< The option name. */
+       rte_option_cb cb;          /**< Function called when option is used. */
+       int enabled;               /**< Set when the option is used. */
+};
+
+/**
+ * @warning
+ * @b EXPERIMENTAL: this API may change without prior notice
+ *
+ * Register an option to the EAL command line.
+ * When recognized, the associated function will be executed at the end of EAL
+ * initialization.
+ *
+ * The associated structure must be available the whole time this option is
+ * registered (i.e. not stack memory).
+ *
+ * @param opt
+ *  Structure describing the option to parse.
+ */
+void __rte_experimental
+rte_option_register(struct rte_option *opt);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif

diff --git a/lib/librte_eal/common/meson.build b/lib/librte_eal/common/meson.build
index 04c414356507926a6202f8fc6f74c1d3a367139f..2a10d57d885e91aa0686f9ae025ca6c83555a9ce 100644 (file)
--- a/lib/librte_eal/common/meson.build
+++ b/lib/librte_eal/common/meson.build
@@ -34,6 +34,7 @@ common_sources = files(
        'malloc_mp.c',
        'rte_keepalive.c',
        'rte_malloc.c',
+       'rte_option.c',
        'rte_reciprocal.c',
        'rte_service.c'
 )
@@ -71,6 +72,7 @@ common_headers = files(
        'include/rte_malloc_heap.h',
        'include/rte_memory.h',
        'include/rte_memzone.h',
+       'include/rte_option.h',
        'include/rte_pci_dev_feature_defs.h',
        'include/rte_pci_dev_features.h',
        'include/rte_per_lcore.h',

diff --git a/lib/librte_eal/common/rte_option.c b/lib/librte_eal/common/rte_option.c
new file mode 100644 (file)
index 0000000..02d59a8
--- /dev/null
+++ b/lib/librte_eal/common/rte_option.c
@@ -0,0 +1,54 @@
+/* SPDX-License-Identifier: BSD-3-Clause
+ * Copyright(c) 2018 Intel Corporation.
+ */
+
+#include <unistd.h>
+#include <string.h>
+
+#include <rte_eal.h>
+#include <rte_option.h>
+
+#include "eal_private.h"
+
+TAILQ_HEAD(rte_option_list, rte_option);
+
+struct rte_option_list rte_option_list =
+       TAILQ_HEAD_INITIALIZER(rte_option_list);
+
+static struct rte_option *option;
+
+int
+rte_option_parse(const char *opt)
+{
+       /* Check if the option is registered */
+       TAILQ_FOREACH(option, &rte_option_list, next) {
+               if (strcmp(opt, option->opt_str) == 0) {
+                       option->enabled = 1;
+                       return 0;
+               }
+       }
+
+       return -1;
+}
+
+void __rte_experimental
+rte_option_register(struct rte_option *opt)
+{
+       TAILQ_FOREACH(option, &rte_option_list, next) {
+               if (strcmp(opt->opt_str, option->opt_str) == 0)
+                       RTE_LOG(INFO, EAL, "Option %s has already been registered.",
+                                       opt->opt_str);
+                       return;
+       }
+
+       TAILQ_INSERT_HEAD(&rte_option_list, opt, next);
+}
+
+void
+rte_option_init(void)
+{
+       TAILQ_FOREACH(option, &rte_option_list, next) {
+               if (option->enabled)
+                       option->cb();
+       }
+}

diff --git a/lib/librte_eal/linuxapp/eal/Makefile b/lib/librte_eal/linuxapp/eal/Makefile
index 72808859469858e1fc31ad2cd63f24dd99ce7307..51deb579746bb72d050469da7c19f7a84f923ba7 100644 (file)
--- a/lib/librte_eal/linuxapp/eal/Makefile
+++ b/lib/librte_eal/linuxapp/eal/Makefile
@@ -75,6 +75,7 @@ SRCS-$(CONFIG_RTE_EXEC_ENV_LINUXAPP) += malloc_elem.c
 SRCS-$(CONFIG_RTE_EXEC_ENV_LINUXAPP) += malloc_heap.c
 SRCS-$(CONFIG_RTE_EXEC_ENV_LINUXAPP) += malloc_mp.c
 SRCS-$(CONFIG_RTE_EXEC_ENV_LINUXAPP) += rte_keepalive.c
+SRCS-$(CONFIG_RTE_EXEC_ENV_LINUXAPP) += rte_option.c
 SRCS-$(CONFIG_RTE_EXEC_ENV_LINUXAPP) += rte_service.c
 SRCS-$(CONFIG_RTE_EXEC_ENV_LINUXAPP) += rte_reciprocal.c
 

diff --git a/lib/librte_eal/linuxapp/eal/eal.c b/lib/librte_eal/linuxapp/eal/eal.c
index 76536bae296dfd2309e6eead1fc6bd44f1c52caf..930070e437e88c11fe8f0c629288efca018db95a 100644 (file)
--- a/lib/librte_eal/linuxapp/eal/eal.c
+++ b/lib/librte_eal/linuxapp/eal/eal.c
@@ -48,6 +48,7 @@
 #include <rte_atomic.h>
 #include <malloc_heap.h>
 #include <rte_vfio.h>
+#include <rte_option.h>
 
 #include "eal_private.h"
 #include "eal_thread.h"
@@ -600,12 +601,20 @@ eal_parse_args(int argc, char **argv)
 
        argvopt = argv;
        optind = 1;
+       opterr = 0;
 
        while ((opt = getopt_long(argc, argvopt, eal_short_options,
                                  eal_long_options, &option_index)) != EOF) {
 
-               /* getopt is not happy, stop right now */
+               /*
+                * getopt didn't recognise the option, lets parse the
+                * registered options to see if the flag is valid
+                */
                if (opt == '?') {
+                       ret = rte_option_parse(argv[optind-1]);
+                       if (ret == 0)
+                               continue;
+
                        eal_usage(prgname);
                        ret = -1;
                        goto out;
@@ -1080,6 +1089,9 @@ rte_eal_init(int argc, char **argv)
 
        rte_eal_mcfg_complete();
 
+       /* Call each registered callback, if enabled */
+       rte_option_init();
+
        return fctret;
 }
 

diff --git a/lib/librte_eal/rte_eal_version.map b/lib/librte_eal/rte_eal_version.map
index f4a2b38fdb55c6ea1411c09a7fcff664c9c52626..5b6d91ffd4ebec87e0b82971e45fed8b5c84e64d 100644 (file)
--- a/lib/librte_eal/rte_eal_version.map
+++ b/lib/librte_eal/rte_eal_version.map
@@ -350,6 +350,7 @@ EXPERIMENTAL {
        rte_mp_request_sync;
        rte_mp_request_async;
        rte_mp_sendmsg;
+       rte_option_register;
        rte_service_lcore_attr_get;
        rte_service_lcore_attr_reset_all;
        rte_service_may_be_active;