From 6c8af3ef7adf8d79983ece0a54d4b9f5fae32e9b Mon Sep 17 00:00:00 2001
From: Liu Xiaodong <xiaodong.liu@intel.com>
Date: Thu, 29 Nov 2018 21:37:53 -0500
Subject: [PATCH] lib/trace: group registration check

Ensure that no trace point group IDs are ever duplicated.
Arrange trace registration in order on tgroup_id.

Change-Id: Id72600257780b1ab95b25c85daaa78c392a9479f
Signed-off-by: Liu Xiaodong <xiaodong.liu@intel.com>
Reviewed-on: https://review.gerrithub.io/435571
Tested-by: SPDK CI Jenkins <sys_sgci@intel.com>
Chandler-Test-Pool: SPDK Automated Test System <sys_sgsw@intel.com>
Reviewed-by: Shuhei Matsumoto <shuhei.matsumoto.xt@hitachi.com>
Reviewed-by: Jim Harris <james.r.harris@intel.com>
Reviewed-by: Ben Walker <benjamin.walker@intel.com>
Reviewed-by: Darek Stojaczyk <dariusz.stojaczyk@intel.com>
---
 lib/trace/trace_flags.c | 39 +++++++++++++++++++++++++++++++++++++--
 1 file changed, 37 insertions(+), 2 deletions(-)

diff --git a/lib/trace/trace_flags.c b/lib/trace/trace_flags.c
index 5176465d0..54a40a3b2 100644
--- a/lib/trace/trace_flags.c
+++ b/lib/trace/trace_flags.c
@@ -178,8 +178,43 @@ spdk_trace_register_description(const char *name, const char *short_name,
 void
 spdk_trace_add_register_fn(struct spdk_trace_register_fn *reg_fn)
 {
-	reg_fn->next = g_reg_fn_head;
-	g_reg_fn_head = reg_fn;
+	struct spdk_trace_register_fn *_reg_fn;
+
+	if (reg_fn->name == NULL) {
+		SPDK_ERRLOG("missing name for registering spdk trace tpoint group\n");
+		assert(false);
+		return;
+	}
+
+	/* Ensure that no trace point group IDs and names are ever duplicated */
+	for (_reg_fn = g_reg_fn_head; _reg_fn; _reg_fn = _reg_fn->next) {
+		if (reg_fn->tgroup_id == _reg_fn->tgroup_id) {
+			SPDK_ERRLOG("duplicate tgroup_id (%d) with %s\n", _reg_fn->tgroup_id, _reg_fn->name);
+			assert(false);
+			return;
+		}
+
+		if (strcmp(reg_fn->name, _reg_fn->name) == 0) {
+			SPDK_ERRLOG("duplicate name with %s\n", _reg_fn->name);
+			assert(false);
+			return;
+		}
+	}
+
+	/* Arrange trace registration in order on tgroup_id */
+	if (g_reg_fn_head == NULL || reg_fn->tgroup_id < g_reg_fn_head->tgroup_id) {
+		reg_fn->next = g_reg_fn_head;
+		g_reg_fn_head = reg_fn;
+		return;
+	}
+
+	for (_reg_fn = g_reg_fn_head; _reg_fn; _reg_fn = _reg_fn->next) {
+		if (_reg_fn->next == NULL || reg_fn->tgroup_id < _reg_fn->next->tgroup_id) {
+			reg_fn->next = _reg_fn->next;
+			_reg_fn->next = reg_fn;
+			return;
+		}
+	}
 }
 
 void