event/rpc: Add framework_get_reactors RPC

Add an new RPC `framework_get_reactors` to retrieve list of all
reactors.  Running threads on each reactor are included
in the output.  Update jsonrpc.md and CHANGELOG accordingly.

Signed-off-by: Shuhei Matsumoto <shuhei.matsumoto.xt@hitachi.com>
Change-Id: I985d087dd41afe3033b7678af141ec8e5a2a822e
Reviewed-on: https://review.gerrithub.io/c/spdk/spdk/+/478027
Tested-by: SPDK CI Jenkins <sys_sgci@intel.com>
Community-CI: SPDK CI Jenkins <sys_sgci@intel.com>
Reviewed-by: Jim Harris <james.r.harris@intel.com>
Reviewed-by: Tomasz Zawadzki <tomasz.zawadzki@intel.com>
Reviewed-by: Alexey Marchuk <alexeymar@mellanox.com>

CHANGELOG.md

@@ -45,6 +45,8 @@ processing function. Batching is controlled by 'delay_cmd_submit' qpair option.
 
 Added optional 'delay_cmd_submit' parameter to 'bdev_nvme_set_options' RPC method.
 
+An new RPC `framework_get_reactors` has been added to retrieve list of all reactors.
+
 ### dpdk
 
 Updated DPDK submodule to DPDK 19.11.

doc/jsonrpc.md

@@ -485,6 +485,50 @@ Example response:
 }
 ~~~
 
+## framework_get_reactors {#rpc_framework_get_reactors}
+
+Retrieve an array of all reactors.
+
+### Parameters
+
+This method has no parameters.
+
+### Response
+
+The response is an array of all reactors.
+
+### Example
+
+Example request:
+~~~
+{
+  "jsonrpc": "2.0",
+  "method": "framework_get_reactors",
+  "id": 1
+}
+~~~
+
+Example response:
+~~~
+{
+  "jsonrpc": "2.0",
+  "id": 1,
+  "result": {
+    "reactors": [
+      {
+        "lcore": 0,
+        "lw_threads": [
+          {
+            "name": "app_thread",
+            "cpumask": "1"
+          }
+        ]
+      }
+    ]
+  }
+}
+~~~
+
 ## thread_get_stats {#rpc_thread_get_stats}
 
 Retrieve current statistics of all the threads.

module/event/rpc/app_rpc.c

@@ -41,6 +41,7 @@
 #include "spdk/thread.h"
 
 #include "spdk_internal/log.h"
+#include "spdk_internal/event.h"
 
 struct rpc_spdk_kill_instance {
 	char *sig_name;
@@ -152,7 +153,7 @@ SPDK_RPC_REGISTER("framework_monitor_context_switch", spdk_rpc_framework_monitor
 		  SPDK_RPC_RUNTIME)
 SPDK_RPC_REGISTER_ALIAS_DEPRECATED(framework_monitor_context_switch, context_switch_monitor)
 
-struct rpc_thread_get_stats_ctx {
+struct rpc_get_stats_ctx {
 	struct spdk_jsonrpc_request *request;
 	struct spdk_json_write_ctx *w;
 };
@@ -160,7 +161,7 @@ struct rpc_thread_get_stats_ctx {
 static void
 rpc_thread_get_stats_done(void *arg)
 {
-	struct rpc_thread_get_stats_ctx *ctx = arg;
+	struct rpc_get_stats_ctx *ctx = arg;
 
 	spdk_json_write_array_end(ctx->w);
 	spdk_json_write_object_end(ctx->w);
@@ -172,7 +173,7 @@ rpc_thread_get_stats_done(void *arg)
 static void
 rpc_thread_get_stats(void *arg)
 {
-	struct rpc_thread_get_stats_ctx *ctx = arg;
+	struct rpc_get_stats_ctx *ctx = arg;
 	struct spdk_thread *thread = spdk_get_thread();
 	struct spdk_thread_stats stats;
 
@@ -191,7 +192,7 @@ static void
 spdk_rpc_thread_get_stats(struct spdk_jsonrpc_request *request,
 			  const struct spdk_json_val *params)
 {
-	struct rpc_thread_get_stats_ctx *ctx;
+	struct rpc_get_stats_ctx *ctx;
 
 	if (params) {
 		spdk_jsonrpc_send_error_response(request, SPDK_JSONRPC_ERROR_INVALID_PARAMS,
@@ -216,3 +217,76 @@ spdk_rpc_thread_get_stats(struct spdk_jsonrpc_request *request,
 }
 
 SPDK_RPC_REGISTER("thread_get_stats", spdk_rpc_thread_get_stats, SPDK_RPC_RUNTIME)
+
+static void
+rpc_framework_get_reactors_done(void *arg1, void *arg2)
+{
+	struct rpc_get_stats_ctx *ctx = arg1;
+
+	spdk_json_write_array_end(ctx->w);
+	spdk_json_write_object_end(ctx->w);
+	spdk_jsonrpc_end_result(ctx->request, ctx->w);
+
+	free(ctx);
+}
+
+static void
+rpc_framework_get_reactors(void *arg1, void *arg2)
+{
+	struct rpc_get_stats_ctx *ctx = arg1;
+	uint32_t current_core;
+	struct spdk_reactor *reactor;
+	struct spdk_lw_thread *lw_thread;
+	struct spdk_thread *thread;
+
+	current_core = spdk_env_get_current_core();
+	reactor = spdk_reactor_get(current_core);
+
+	spdk_json_write_object_begin(ctx->w);
+	spdk_json_write_named_uint32(ctx->w, "lcore", current_core);
+
+	spdk_json_write_named_array_begin(ctx->w, "lw_threads");
+	TAILQ_FOREACH(lw_thread, &reactor->threads, link) {
+		thread = spdk_thread_get_from_ctx(lw_thread);
+
+		spdk_json_write_object_begin(ctx->w);
+		spdk_json_write_named_string(ctx->w, "name", spdk_thread_get_name(thread));
+		spdk_json_write_named_string(ctx->w, "cpumask",
+					     spdk_cpuset_fmt(spdk_thread_get_cpumask(thread)));
+		spdk_json_write_object_end(ctx->w);
+	}
+	spdk_json_write_array_end(ctx->w);
+
+	spdk_json_write_object_end(ctx->w);
+}
+
+static void
+spdk_rpc_framework_get_reactors(struct spdk_jsonrpc_request *request,
+				const struct spdk_json_val *params)
+{
+	struct rpc_get_stats_ctx *ctx;
+
+	if (params) {
+		spdk_jsonrpc_send_error_response(request, SPDK_JSONRPC_ERROR_INVALID_PARAMS,
+						 "`framework_get_reactors` requires no arguments");
+		return;
+	}
+
+	ctx = calloc(1, sizeof(*ctx));
+	if (!ctx) {
+		spdk_jsonrpc_send_error_response(request, SPDK_JSONRPC_ERROR_INTERNAL_ERROR,
+						 "Memory allocation error");
+		return;
+	}
+
+	ctx->request = request;
+	ctx->w = spdk_jsonrpc_begin_result(ctx->request);
+
+	spdk_json_write_object_begin(ctx->w);
+	spdk_json_write_named_array_begin(ctx->w, "reactors");
+
+	spdk_for_each_reactor(rpc_framework_get_reactors, ctx, NULL,
+			      rpc_framework_get_reactors_done);
+}
+
+SPDK_RPC_REGISTER("framework_get_reactors", spdk_rpc_framework_get_reactors, SPDK_RPC_RUNTIME)

scripts/rpc.py

@@ -135,6 +135,13 @@ if __name__ == "__main__":
     p.add_argument('-d', '--disable', action='store_true', help='Disable context switch monitoring')
     p.set_defaults(func=framework_monitor_context_switch)
 
+    def framework_get_reactors(args):
+        print_dict(rpc.app.framework_get_reactors(args.client))
+
+    p = subparsers.add_parser(
+        'framework_get_reactors', help='Display list of all reactors')
+    p.set_defaults(func=framework_get_reactors)
+
     # bdev
     def bdev_set_options(args):
         rpc.bdev.bdev_set_options(args.client,

scripts/rpc/app.py

@@ -28,6 +28,15 @@ def framework_monitor_context_switch(client, enabled=None):
     return client.call('framework_monitor_context_switch', params)
 
 
+def framework_get_reactors(client):
+    """Query list of all reactors.
+
+    Returns:
+        List of all reactors.
+    """
+    return client.call('framework_get_reactors')
+
+
 def thread_get_stats(client):
     """Query threads statistics.