[dpdk-dev] [PATCH v2] eal: initialize alarms early

[Darek Stojaczyk <dariusz.stojaczyk@intel.com>]

On linux, we currently initialize rte_alarms after
starting to listen for IPC hotplug requests, which gives
us a data race window. Upon receiving such hotplug
request we always try to set an alarm and this obviously
doesn't work if the alarms weren't initialized yet.

To fix it, we initialize alarms before starting to
listen for IPC hotplug messages. Specifically, we move
rte_eal_alarm_init() right after rte_eal_intr_init() as
it makes some sense to keep those two close to each other.

We update the bsd code as well to keep the initialization
order the same in both eal implementations.

Fixes: 244d5130719c ("eal: enable hotplug on multi-process")
Cc: Qi Zhang <qi.z.zhang@intel.com>
Cc: Anatoly Burakov <anatoly.burakov@intel.com>
Cc: stable@dpdk.org

Signed-off-by: Darek Stojaczyk <dariusz.stojaczyk@intel.com>
---
v2:
 - updated the bsd code as well (Thomas)


 lib/librte_eal/freebsd/eal/eal.c | 12 ++++++------
 lib/librte_eal/linux/eal/eal.c   | 12 ++++++------
 2 files changed, 12 insertions(+), 12 deletions(-)

diff --git a/lib/librte_eal/freebsd/eal/eal.c b/lib/librte_eal/freebsd/eal/eal.c
index 4e86b10b1..790c6afa7 100644
--- a/lib/librte_eal/freebsd/eal/eal.c
+++ b/lib/librte_eal/freebsd/eal/eal.c
@@ -662,6 +662,12 @@ rte_eal_init(int argc, char **argv)
 		return -1;
 	}
 
+	if (rte_eal_alarm_init() < 0) {
+		rte_eal_init_alert("Cannot init interrupt-handling thread");
+		/* rte_eal_alarm_init sets rte_errno on failure. */
+		return -1;
+	}
+
 	/* Put mp channel init before bus scan so that we can init the vdev
 	 * bus through mp channel in the secondary process before the bus scan.
 	 */
@@ -751,12 +757,6 @@ rte_eal_init(int argc, char **argv)
 		return -1;
 	}
 
-	if (rte_eal_alarm_init() < 0) {
-		rte_eal_init_alert("Cannot init interrupt-handling thread");
-		/* rte_eal_alarm_init sets rte_errno on failure. */
-		return -1;
-	}
-
 	if (rte_eal_timer_init() < 0) {
 		rte_eal_init_alert("Cannot init HPET or TSC timers");
 		rte_errno = ENOTSUP;
diff --git a/lib/librte_eal/linux/eal/eal.c b/lib/librte_eal/linux/eal/eal.c
index 13f401684..75ed0cf10 100644
--- a/lib/librte_eal/linux/eal/eal.c
+++ b/lib/librte_eal/linux/eal/eal.c
@@ -1005,6 +1005,12 @@ rte_eal_init(int argc, char **argv)
 		return -1;
 	}
 
+	if (rte_eal_alarm_init() < 0) {
+		rte_eal_init_alert("Cannot init interrupt-handling thread");
+		/* rte_eal_alarm_init sets rte_errno on failure. */
+		return -1;
+	}
+
 	/* Put mp channel init before bus scan so that we can init the vdev
 	 * bus through mp channel in the secondary process before the bus scan.
 	 */
@@ -1125,12 +1131,6 @@ rte_eal_init(int argc, char **argv)
 		return -1;
 	}
 
-	if (rte_eal_alarm_init() < 0) {
-		rte_eal_init_alert("Cannot init interrupt-handling thread");
-		/* rte_eal_alarm_init sets rte_errno on failure. */
-		return -1;
-	}
-
 	if (rte_eal_timer_init() < 0) {
 		rte_eal_init_alert("Cannot init HPET or TSC timers");
 		rte_errno = ENOTSUP;
-- 
2.17.1