From b01421cf2672b659313e77f26e1b885a3d8c28f4 Mon Sep 17 00:00:00 2001 From: =?utf8?q?J=C3=A9r=C3=A9mie=20Galarneau?= Date: Tue, 18 Nov 2014 14:09:36 -0500 Subject: [PATCH] Fix: Missing rcu_read_lock in save_domains() MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit Signed-off-by: Jérémie Galarneau --- src/bin/lttng-sessiond/save.c | 45 +++++++++++++++++++++-------------- 1 file changed, 27 insertions(+), 18 deletions(-) diff --git a/src/bin/lttng-sessiond/save.c b/src/bin/lttng-sessiond/save.c index 908e5f8fd..d231fb24f 100644 --- a/src/bin/lttng-sessiond/save.c +++ b/src/bin/lttng-sessiond/save.c @@ -1223,6 +1223,8 @@ int save_domains(struct config_writer *writer, struct ltt_session *session) } if (session->ust_session) { + unsigned long agent_count; + ret = config_writer_open_element(writer, config_element_domain); if (ret) { @@ -1241,30 +1243,37 @@ int save_domains(struct config_writer *writer, struct ltt_session *session) ret = LTTNG_ERR_SAVE_IO_FAIL; goto end; } - } - if (session->ust_session && - lttng_ht_get_count(session->ust_session->agents) > 0) { - ret = config_writer_open_element(writer, - config_element_domain); - if (ret) { - ret = LTTNG_ERR_SAVE_IO_FAIL; - goto end; - } + rcu_read_lock(); + agent_count = + lttng_ht_get_count(session->ust_session->agents); + rcu_read_unlock(); - ret = save_ust_session(writer, session, 1); - if (ret) { - goto end; - } + if (agent_count > 0) { + ret = config_writer_open_element(writer, + config_element_domain); + if (ret) { + ret = LTTNG_ERR_SAVE_IO_FAIL; + goto end; + } - /* /domain */ - ret = config_writer_close_element(writer); - if (ret) { - ret = LTTNG_ERR_SAVE_IO_FAIL; - goto end; + ret = save_ust_session(writer, session, 1); + if (ret) { + goto end; + } + + /* /domain */ + ret = config_writer_close_element(writer); + if (ret) { + ret = LTTNG_ERR_SAVE_IO_FAIL; + goto end; + } } } + if (session->ust_session) { + } + /* /domains */ ret = config_writer_close_element(writer); if (ret) { -- 2.34.1