From ee8134099afdbcb21aa13433e91837ae15b59afe Mon Sep 17 00:00:00 2001
From: Shuhei Matsumoto <shuhei.matsumoto.xt@hitachi.com>
Date: Wed, 19 Feb 2020 21:10:04 -0500
Subject: [PATCH] lib/thread: Add spdk_thread_get_by_id() API to get thread
 whose ID matches

Add an new API spdk_thread_get_by_id(). This will be used in the
subsequent patches to set the cpumask of the running thread to the
specified value.

Signed-off-by: Shuhei Matsumoto <shuhei.matsumoto.xt@hitachi.com>
Change-Id: Ib5d02b9d7b499477c43e6527cf8f603d8323e063
Reviewed-on: https://review.spdk.io/gerrit/c/spdk/spdk/+/966
Tested-by: SPDK CI Jenkins <sys_sgci@intel.com>
Reviewed-by: Darek Stojaczyk <dariusz.stojaczyk@intel.com>
Reviewed-by: Ben Walker <benjamin.walker@intel.com>
Reviewed-by: Aleksey Marchuk <alexeymar@mellanox.com>
Reviewed-by: Jim Harris <james.r.harris@intel.com>
---
 include/spdk/thread.h |  8 ++++++++
 lib/thread/thread.c   | 18 ++++++++++++++++++
 2 files changed, 26 insertions(+)

diff --git a/include/spdk/thread.h b/include/spdk/thread.h
index 90c96c31b..3f1e73006 100644
--- a/include/spdk/thread.h
+++ b/include/spdk/thread.h
@@ -372,6 +372,14 @@ const char *spdk_thread_get_name(const struct spdk_thread *thread);
  */
 uint64_t spdk_thread_get_id(const struct spdk_thread *thread);
 
+/**
+ * Get the thread by the ID.
+ *
+ * \param id ID of the thread.
+ * \return Thread whose ID matches or NULL otherwise.
+ */
+struct spdk_thread *spdk_thread_get_by_id(uint64_t id);
+
 struct spdk_thread_stats {
 	uint64_t busy_tsc;
 	uint64_t idle_tsc;
diff --git a/lib/thread/thread.c b/lib/thread/thread.c
index 5db66b708..600ef75d9 100644
--- a/lib/thread/thread.c
+++ b/lib/thread/thread.c
@@ -735,6 +735,24 @@ spdk_thread_get_id(const struct spdk_thread *thread)
 	return thread->id;
 }
 
+struct spdk_thread *
+spdk_thread_get_by_id(uint64_t id)
+{
+	struct spdk_thread *thread;
+
+	pthread_mutex_lock(&g_devlist_mutex);
+	TAILQ_FOREACH(thread, &g_threads, tailq) {
+		if (thread->id == id) {
+			pthread_mutex_unlock(&g_devlist_mutex);
+
+			return thread;
+		}
+	}
+	pthread_mutex_unlock(&g_devlist_mutex);
+
+	return NULL;
+}
+
 int
 spdk_thread_get_stats(struct spdk_thread_stats *stats)
 {