From: Mark Stapp <mstapp@nvidia.com>
Date: Tue, 6 Sep 2022 12:34:10 +0000 (-0700)
Subject: bgpd: release rcu lock in bgp keepalive pthread
X-Git-Tag: frr-8.3.2~1^2
X-Git-Url: https://git.puffer.fish/?a=commitdiff_plain;h=74d699cb8b794da51d48cbaf29769f068d89ccbc;p=matthieu%2Ffrr.git

bgpd: release rcu lock in bgp keepalive pthread

Don't hold the rcu lock in the bgp keepalive pthread: it
blocks the rcu pthread and prevents log-file deletion.

Signed-off-by: Mark Stapp <mstapp@nvidia.com>
(cherry picked from commit 85ba04f3897d3c9def83d8b291b6c6a276e96c54)
---

diff --git a/bgpd/bgp_keepalives.c b/bgpd/bgp_keepalives.c
index 86202a0e3d..d0eb249d38 100644
--- a/bgpd/bgp_keepalives.c
+++ b/bgpd/bgp_keepalives.c
@@ -175,6 +175,15 @@ void *bgp_keepalives_start(void *arg)
 	struct timeval next_update = {0, 0};
 	struct timespec next_update_ts = {0, 0};
 
+	/*
+	 * The RCU mechanism for each pthread is initialized in a "locked"
+	 * state. That's ok for pthreads using the frr_pthread,
+	 * thread_fetch event loop, because that event loop unlocks regularly.
+	 * For foreign pthreads, the lock needs to be unlocked so that the
+	 * background rcu pthread can run.
+	 */
+	rcu_read_unlock();
+
 	peerhash_mtx = XCALLOC(MTYPE_TMP, sizeof(pthread_mutex_t));
 	peerhash_cond = XCALLOC(MTYPE_TMP, sizeof(pthread_cond_t));