From 885bc995964b5cc7b3b3e923b1ead6a3b968cd96 Mon Sep 17 00:00:00 2001
From: JinYu <jin.yu@intel.com>
Date: Thu, 10 Jan 2019 21:10:42 +0800
Subject: [PATCH] nvme/hotplug: add ctrlr a timeout callback in hotplug example

The example would endlessly loop in unregister_dev()->spdk_nvme_
ctrlr_free_io_qpair(), if the device has been removed after leave
hotplug monitoring. Add the timeout callback to handle this corner
case. The case will not be friendly to newcomers, if we use the event
framework to update it, because the hotplug has been hidden in frame
work.

Change-Id: I33a81efd356fdf1e7921f5721e9d95936470e8b0
Signed-off-by: JinYu <jin.yu@intel.com>
Reviewed-on: https://review.gerrithub.io/c/439822
Tested-by: SPDK CI Jenkins <sys_sgci@intel.com>
Reviewed-by: Changpeng Liu <changpeng.liu@intel.com>
Reviewed-by: Jim Harris <james.r.harris@intel.com>
---
 examples/nvme/hotplug/hotplug.c | 20 +++++++++++++++++++-
 1 file changed, 19 insertions(+), 1 deletion(-)

diff --git a/examples/nvme/hotplug/hotplug.c b/examples/nvme/hotplug/hotplug.c
index 456a5194f..104accc08 100644
--- a/examples/nvme/hotplug/hotplug.c
+++ b/examples/nvme/hotplug/hotplug.c
@@ -36,6 +36,7 @@
 #include "spdk/nvme.h"
 #include "spdk/queue.h"
 #include "spdk/string.h"
+#include "spdk/util.h"
 
 struct dev_ctx {
 	TAILQ_ENTRY(dev_ctx)	tailq;
@@ -71,10 +72,21 @@ static int g_expected_removal_times = -1;
 static int g_insert_times;
 static int g_removal_times;
 static int g_shm_id = -1;
+static uint64_t g_timeout_in_us = SPDK_SEC_TO_USEC;
 
 static void
 task_complete(struct perf_task *task);
 
+static void
+timeout_cb(void *cb_arg, struct spdk_nvme_ctrlr *ctrlr,
+	   struct spdk_nvme_qpair *qpair, uint16_t cid)
+{
+	/* leave hotplug monitor loop, use the timeout_cb to monitor the hotplug */
+	if (spdk_nvme_probe(NULL, NULL, NULL, NULL, NULL) != 0) {
+		fprintf(stderr, "spdk_nvme_probe() failed\n");
+	}
+}
+
 static void
 register_dev(struct spdk_nvme_ctrlr *ctrlr)
 {
@@ -94,6 +106,8 @@ register_dev(struct spdk_nvme_ctrlr *ctrlr)
 	dev->is_removed = false;
 	dev->is_draining = false;
 
+	spdk_nvme_ctrlr_register_timeout_callback(ctrlr, g_timeout_in_us, timeout_cb, NULL);
+
 	dev->ns = spdk_nvme_ctrlr_get_ns(ctrlr, 1);
 
 	if (!dev->ns || !spdk_nvme_ns_is_active(dev->ns)) {
@@ -388,6 +402,7 @@ static void usage(char *program_name)
 {
 	printf("%s options", program_name);
 	printf("\n");
+	printf("\t[-c timeout for each command in second(default:1s)]\n");
 	printf("\t[-i shm id (optional)]\n");
 	printf("\t[-n expected hot insert times]\n");
 	printf("\t[-r expected hot removal times]\n");
@@ -403,7 +418,7 @@ parse_args(int argc, char **argv)
 	/* default value */
 	g_time_in_sec = 0;
 
-	while ((op = getopt(argc, argv, "i:n:r:t:")) != -1) {
+	while ((op = getopt(argc, argv, "c:i:n:r:t:")) != -1) {
 		if (op == '?') {
 			usage(argv[0]);
 			return 1;
@@ -415,6 +430,9 @@ parse_args(int argc, char **argv)
 			return val;
 		}
 		switch (op) {
+		case 'c':
+			g_timeout_in_us = val * SPDK_SEC_TO_USEC;
+			break;
 		case 'i':
 			g_shm_id = val;
 			break;