From 428de77a3148b53f46d62c62da781f972c767ab7 Mon Sep 17 00:00:00 2001 From: Mathieu Desnoyers Date: Mon, 11 Nov 2013 10:28:05 -0500 Subject: [PATCH] Cleanup: sessiond jul.c comments and error path Signed-off-by: Mathieu Desnoyers --- src/bin/lttng-sessiond/jul.c | 31 ++++++++++++++++++------------- 1 file changed, 18 insertions(+), 13 deletions(-) diff --git a/src/bin/lttng-sessiond/jul.c b/src/bin/lttng-sessiond/jul.c index 8b57b8d70..c4d81217a 100644 --- a/src/bin/lttng-sessiond/jul.c +++ b/src/bin/lttng-sessiond/jul.c @@ -27,7 +27,7 @@ #include "utils.h" /* - * URCU intermediate call to complete destroy a JUL event. + * URCU delayed JUL event reclaim. */ static void destroy_event_jul_rcu(struct rcu_head *head) { @@ -40,7 +40,7 @@ static void destroy_event_jul_rcu(struct rcu_head *head) } /* - * URCU intermediate call to complete destroy a JUL event. + * URCU delayed JUL app reclaim. */ static void destroy_app_jul_rcu(struct rcu_head *head) { @@ -53,8 +53,8 @@ static void destroy_app_jul_rcu(struct rcu_head *head) } /* - * Communication with Java agent call. Send the message header to the given - * socket all in big endian. + * Communication with Java agent. Send the message header to the given + * socket in big endian. * * Return 0 on success or else a negative errno message of sendmsg() op. */ @@ -135,9 +135,11 @@ error: /* - * Internal call to list events on a given app. Populate events. + * Internal event listing for a given app. Populate events. * * Return number of element in the list or else a negative LTTNG_ERR* code. + * On success, the caller is responsible for freeing the memory + * allocated for "events". */ static ssize_t list_events(struct jul_app *app, struct lttng_event **events) { @@ -220,7 +222,7 @@ error: } /* - * Internal enable JUL event call on a JUL application. This function + * Internal enable JUL event on a JUL application. This function * communicates with the Java agent to enable a given event (Logger name). * * Return LTTNG_OK on success or else a LTTNG_ERR* code. @@ -436,8 +438,7 @@ int jul_list_events(struct lttng_event **events) nb_ev = list_events(app, &jul_events); if (nb_ev < 0) { ret = nb_ev; - rcu_read_unlock(); - goto error; + goto error_unlock; } if (count >= nbmem) { @@ -451,9 +452,8 @@ int jul_list_events(struct lttng_event **events) if (!ptr) { PERROR("realloc JUL events"); ret = -ENOMEM; - rcu_read_unlock(); free(jul_events); - goto error; + goto error_unlock; } tmp_events = ptr; } @@ -468,6 +468,8 @@ int jul_list_events(struct lttng_event **events) *events = tmp_events; return ret; +error_unlock: + rcu_read_unlock(); error: free(tmp_events); return ret; @@ -618,7 +620,8 @@ void jul_delete_app(struct jul_app *app) /* * Destroy a JUL application object by detaching it from its corresponding UST - * app if one, closing the socket and freeing the memory. + * app if one is connected by closing the socket. Finally, perform a + * delayed memory reclaim. */ void jul_destroy_app(struct jul_app *app) { @@ -751,7 +754,9 @@ void jul_delete_event(struct jul_event *event, struct jul_domain *dom) } /* - * Free given JUl event. After this call, the pointer is not usable anymore. + * Free given JUL event. This event must not be globally visible at this + * point (only expected to be used on failure just after event + * creation). After this call, the pointer is not usable anymore. */ void jul_destroy_event(struct jul_event *event) { @@ -762,7 +767,7 @@ void jul_destroy_event(struct jul_event *event) /* * Destroy a JUL domain completely. Note that the given pointer is NOT freed - * thus a reference can be passed to this function. + * thus a reference to static or stack data can be passed to this function. */ void jul_destroy_domain(struct jul_domain *dom) { -- 2.34.1