subsystem: add per module configuration dump

Change-Id: I5c4e51cd9cd97b05ab9a95cbe084ff2741f6ef58
Signed-off-by: Pawel Wodkowski <pawelx.wodkowski@intel.com>
Reviewed-on: https://review.gerrithub.io/402323
Reviewed-by: Shuhei Matsumoto <shuhei.matsumoto.xt@hitachi.com>
Tested-by: SPDK Automated Test System <sys_sgsw@intel.com>
Reviewed-by: Jim Harris <james.r.harris@intel.com>

include/spdk_internal/event.h

@@ -37,6 +37,7 @@
 #include "spdk/stdinc.h"
 
 #include "spdk/event.h"
+#include "spdk/json.h"
 
 struct spdk_event {
 	uint32_t		lcore;
@@ -57,12 +58,15 @@ struct spdk_subsystem {
 	void (*init)(void);
 	void (*fini)(void);
 	void (*config)(FILE *fp);
+	int (*write_config_json)(struct spdk_json_write_ctx *w);
 	TAILQ_ENTRY(spdk_subsystem) tailq;
 };
 
 TAILQ_HEAD(spdk_subsystem_list, spdk_subsystem);
 extern struct spdk_subsystem_list g_subsystems;
 
+struct spdk_subsystem *spdk_subsystem_find(struct spdk_subsystem_list *list, const char *name);
+
 struct spdk_subsystem_depend {
 	const char *name;
 	const char *depends_on;
@@ -81,6 +85,15 @@ void spdk_subsystem_init_next(int rc);
 void spdk_subsystem_fini_next(void);
 void spdk_subsystem_config(FILE *fp);
 
+/**
+ * Save pointed subsystem configuration to the JSON write context. In case of
+ * error \c null is written to the JSON context.
+ *
+ * \param w JSON write context
+ * \param subsystem the subsystem to query
+ */
+void spdk_subsystem_config_json(struct spdk_json_write_ctx *w, struct spdk_subsystem *subsystem);
+
 void spdk_rpc_initialize(const char *listen_addr);
 void spdk_rpc_finish(void);
 

lib/event/rpc/subsystem_rpc.c

@@ -33,6 +33,8 @@
 
 #include "spdk_internal/event.h"
 #include "spdk/rpc.h"
+#include "spdk/string.h"
+#include "spdk/util.h"
 
 static void
 spdk_rpc_get_subsystems(struct spdk_jsonrpc_request *request,
@@ -73,3 +75,44 @@ spdk_rpc_get_subsystems(struct spdk_jsonrpc_request *request,
 }
 
 SPDK_RPC_REGISTER("get_subsystems", spdk_rpc_get_subsystems)
+
+struct rpc_get_subsystem_config {
+	char *name;
+};
+
+static const struct spdk_json_object_decoder rpc_get_subsystem_config[] = {
+	{"name", offsetof(struct rpc_get_subsystem_config, name), spdk_json_decode_string},
+};
+
+static void
+spdk_rpc_get_subsystem_config(struct spdk_jsonrpc_request *request,
+			      const struct spdk_json_val *params)
+{
+	struct rpc_get_subsystem_config req = {};
+	struct spdk_json_write_ctx *w;
+	struct spdk_subsystem *subsystem;
+
+	if (spdk_json_decode_object(params, rpc_get_subsystem_config,
+				    SPDK_COUNTOF(rpc_get_subsystem_config), &req)) {
+		spdk_jsonrpc_send_error_response(request, SPDK_JSONRPC_ERROR_INVALID_PARAMS, "Invalid arguments");
+		return;
+	}
+
+	subsystem = spdk_subsystem_find(&g_subsystems, req.name);
+	if (!subsystem) {
+		spdk_jsonrpc_send_error_response_fmt(request, SPDK_JSONRPC_ERROR_INVALID_PARAMS,
+						     "Subsystem '%s' not found", req.name);
+		goto out;
+	}
+
+	w = spdk_jsonrpc_begin_result(request);
+	if (w) {
+		spdk_subsystem_config_json(w, subsystem);
+		spdk_jsonrpc_end_result(request, w);
+	}
+
+out:
+	free(req.name);
+}
+
+SPDK_RPC_REGISTER("get_subsystem_config", spdk_rpc_get_subsystem_config)

lib/event/subsystem.c

@@ -58,7 +58,7 @@ spdk_add_subsystem_depend(struct spdk_subsystem_depend *depend)
 	TAILQ_INSERT_TAIL(&g_subsystems_deps, depend, tailq);
 }
 
-static struct spdk_subsystem *
+struct spdk_subsystem *
 spdk_subsystem_find(struct spdk_subsystem_list *list, const char *name)
 {
 	struct spdk_subsystem *iter;
@@ -242,3 +242,13 @@ spdk_subsystem_config(FILE *fp)
 		}
 	}
 }
+
+void
+spdk_subsystem_config_json(struct spdk_json_write_ctx *w, struct spdk_subsystem *subsystem)
+{
+	if (subsystem && subsystem->write_config_json) {
+		subsystem->write_config_json(w);
+	} else {
+		spdk_json_write_null(w);
+	}
+}

scripts/rpc.py

@@ -437,6 +437,10 @@ if __name__ == "__main__":
     entry contain (unsorted) array of subsystems it depends on.""")
     p.set_defaults(func=rpc.subsystem.get_subsystems)
 
+    p = subparsers.add_parser('get_subsystem_config', help=""""Print subsystem configuration""")
+    p.add_argument('name', help='Name of subsystem to query')
+    p.set_defaults(func=rpc.subsystem.get_subsystem_config)
+
     # vhost
     p = subparsers.add_parser('set_vhost_controller_coalescing', help='Set vhost controller coalescing')
     p.add_argument('ctrlr', help='controller name')

scripts/rpc/subsystem.py

@@ -3,3 +3,8 @@ from client import print_dict, print_array, int_arg
 
 def get_subsystems(args):
     print_dict(args.client.call('get_subsystems'))
+
+
+def get_subsystem_config(args):
+    params = {'name': args.name}
+    print_dict(args.client.call('get_subsystem_config', params))

test/unit/lib/event/subsystem.c/subsystem_ut.c

@@ -35,6 +35,7 @@
 
 #include "spdk_cunit.h"
 
+#include "unit/lib/json_mock.c"
 #include "event/subsystem.c"
 
 static struct spdk_subsystem g_ut_subsystems[8];

test/unit/lib/json_mock.c

@@ -0,0 +1,81 @@
+/*-
+ *   BSD LICENSE
+ *
+ *   Copyright (c) Intel Corporation.
+ *   All rights reserved.
+ *
+ *   Redistribution and use in source and binary forms, with or without
+ *   modification, are permitted provided that the following conditions
+ *   are met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ *       notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above copyright
+ *       notice, this list of conditions and the following disclaimer in
+ *       the documentation and/or other materials provided with the
+ *       distribution.
+ *     * Neither the name of Intel Corporation nor the names of its
+ *       contributors may be used to endorse or promote products derived
+ *       from this software without specific prior written permission.
+ *
+ *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "spdk/json.h"
+#include "spdk_internal/mock.h"
+
+DEFINE_STUB(spdk_json_write_begin, struct spdk_json_write_ctx *, (spdk_json_write_cb write_cb,
+		void *cb_ctx, uint32_t flags), NULL);
+
+DEFINE_STUB(spdk_json_write_end, int, (struct spdk_json_write_ctx *w), 0);
+DEFINE_STUB(spdk_json_write_null, int, (struct spdk_json_write_ctx *w), 0);
+DEFINE_STUB(spdk_json_write_bool, int, (struct spdk_json_write_ctx *w, bool val), 0);
+DEFINE_STUB(spdk_json_write_int32, int, (struct spdk_json_write_ctx *w, int32_t val), 0);
+DEFINE_STUB(spdk_json_write_uint32, int, (struct spdk_json_write_ctx *w, uint32_t val), 0);
+DEFINE_STUB(spdk_json_write_int64, int, (struct spdk_json_write_ctx *w, int64_t val), 0);
+DEFINE_STUB(spdk_json_write_uint64, int, (struct spdk_json_write_ctx *w, uint64_t val), 0);
+DEFINE_STUB(spdk_json_write_string, int, (struct spdk_json_write_ctx *w, const char *val), 0);
+DEFINE_STUB(spdk_json_write_string_raw, int, (struct spdk_json_write_ctx *w, const char *val,
+		size_t len), 0);
+
+DEFINE_STUB(spdk_json_write_array_begin, int, (struct spdk_json_write_ctx *w), 0);
+DEFINE_STUB(spdk_json_write_array_end, int, (struct spdk_json_write_ctx *w), 0);
+DEFINE_STUB(spdk_json_write_object_begin, int, (struct spdk_json_write_ctx *w), 0);
+DEFINE_STUB(spdk_json_write_object_end, int, (struct spdk_json_write_ctx *w), 0);
+DEFINE_STUB(spdk_json_write_name, int, (struct spdk_json_write_ctx *w, const char *name), 0);
+DEFINE_STUB(spdk_json_write_name_raw, int, (struct spdk_json_write_ctx *w, const char *name,
+		size_t len), 0);
+
+/* Utility functions */
+DEFINE_STUB(spdk_json_write_named_null, int, (struct spdk_json_write_ctx *w, const char *name), 0);
+DEFINE_STUB(spdk_json_write_named_bool, int, (struct spdk_json_write_ctx *w, const char *name,
+		bool val), 0);
+DEFINE_STUB(spdk_json_write_named_int32, int, (struct spdk_json_write_ctx *w, const char *name,
+		int32_t val), 0);
+DEFINE_STUB(spdk_json_write_named_uint32, int, (struct spdk_json_write_ctx *w, const char *name,
+		uint32_t val), 0);
+DEFINE_STUB(spdk_json_write_named_uint64, int, (struct spdk_json_write_ctx *w, const char *name,
+		uint64_t val), 0);
+DEFINE_STUB(spdk_json_write_named_int64, int, (struct spdk_json_write_ctx *w, const char *name,
+		int64_t val), 0);
+DEFINE_STUB(spdk_json_write_named_string, int, (struct spdk_json_write_ctx *w, const char *name,
+		const char *val), 0);
+DEFINE_STUB(spdk_json_write_named_string_fmt, int, (struct spdk_json_write_ctx *w, const char *name,
+		const char *fmt, ...), 0);
+DEFINE_STUB(spdk_json_write_named_string_fmt_v, int, (struct spdk_json_write_ctx *w,
+		const char *name, const char *fmt, va_list args), 0);
+
+DEFINE_STUB(spdk_json_write_named_array_begin, int, (struct spdk_json_write_ctx *w,
+		const char *name), 0);
+DEFINE_STUB(spdk_json_write_named_object_begin, int, (struct spdk_json_write_ctx *w,
+		const char *name), 0);