From ef76436c683424e5308b25e1ea1ab50c219e0c84 Mon Sep 17 00:00:00 2001
From: Cunming Liang <cunming.liang@intel.com>
Date: Tue, 17 Feb 2015 10:08:06 +0800
Subject: [PATCH] eal: get unique thread id

The rte_gettid() wraps the linux and freebsd syscall gettid().
It provides a persistent unique thread id for the calling thread.
It will save the unique id in TLS on the first time.

Signed-off-by: Cunming Liang <cunming.liang@intel.com>
Acked-by: Olivier Matz <olivier.matz@6wind.com>
Acked-by: Konstantin Ananyev <konstantin.ananyev@intel.com>
---
 lib/librte_eal/bsdapp/eal/eal_thread.c   |  9 ++++++++
 lib/librte_eal/common/include/rte_eal.h  | 27 ++++++++++++++++++++++++
 lib/librte_eal/linuxapp/eal/eal_thread.c |  7 ++++++
 3 files changed, 43 insertions(+)

diff --git a/lib/librte_eal/bsdapp/eal/eal_thread.c b/lib/librte_eal/bsdapp/eal/eal_thread.c
index ab05368df0..990c0175fc 100644
--- a/lib/librte_eal/bsdapp/eal/eal_thread.c
+++ b/lib/librte_eal/bsdapp/eal/eal_thread.c
@@ -39,6 +39,7 @@
 #include <sched.h>
 #include <pthread_np.h>
 #include <sys/queue.h>
+#include <sys/thr.h>
 
 #include <rte_debug.h>
 #include <rte_atomic.h>
@@ -231,3 +232,11 @@ eal_thread_loop(__attribute__((unused)) void *arg)
 	/* pthread_exit(NULL); */
 	/* return NULL; */
 }
+
+/* require calling thread tid by gettid() */
+int rte_sys_gettid(void)
+{
+	long lwpid;
+	thr_self(&lwpid);
+	return (int)lwpid;
+}
diff --git a/lib/librte_eal/common/include/rte_eal.h b/lib/librte_eal/common/include/rte_eal.h
index f4ecd2e0bb..b72606b8fe 100644
--- a/lib/librte_eal/common/include/rte_eal.h
+++ b/lib/librte_eal/common/include/rte_eal.h
@@ -41,6 +41,9 @@
  */
 
 #include <stdint.h>
+#include <sched.h>
+
+#include <rte_per_lcore.h>
 
 #ifdef __cplusplus
 extern "C" {
@@ -262,6 +265,30 @@ rte_set_application_usage_hook( rte_usage_hook_t usage_func );
  */
 int rte_eal_has_hugepages(void);
 
+/**
+ * A wrap API for syscall gettid.
+ *
+ * @return
+ *   On success, returns the thread ID of calling process.
+ *   It is always successful.
+ */
+int rte_sys_gettid(void);
+
+/**
+ * Get system unique thread id.
+ *
+ * @return
+ *   On success, returns the thread ID of calling process.
+ *   It is always successful.
+ */
+static inline int rte_gettid(void)
+{
+	static RTE_DEFINE_PER_LCORE(int, _thread_id) = -1;
+	if (RTE_PER_LCORE(_thread_id) == -1)
+		RTE_PER_LCORE(_thread_id) = rte_sys_gettid();
+	return RTE_PER_LCORE(_thread_id);
+}
+
 #ifdef __cplusplus
 }
 #endif
diff --git a/lib/librte_eal/linuxapp/eal/eal_thread.c b/lib/librte_eal/linuxapp/eal/eal_thread.c
index 80a985f2f2..0288b22e58 100644
--- a/lib/librte_eal/linuxapp/eal/eal_thread.c
+++ b/lib/librte_eal/linuxapp/eal/eal_thread.c
@@ -39,6 +39,7 @@
 #include <pthread.h>
 #include <sched.h>
 #include <sys/queue.h>
+#include <sys/syscall.h>
 
 #include <rte_debug.h>
 #include <rte_atomic.h>
@@ -231,3 +232,9 @@ eal_thread_loop(__attribute__((unused)) void *arg)
 	/* pthread_exit(NULL); */
 	/* return NULL; */
 }
+
+/* require calling thread tid by gettid() */
+int rte_sys_gettid(void)
+{
+	return (int)syscall(SYS_gettid);
+}
-- 
2.20.1