fix: writeback: Fix sync livelock due to b_dirty_time processing (v5.9)

[lttng-modules.git] / lttng-events.c

diff --git a/lttng-events.c b/lttng-events.c
index b7c183e91f97ca4033506890a4dc9ec47e0191c1..d7192947719e3ee51fb78e630371344f03204b71 100644 (file)
--- a/lttng-events.c
+++ b/lttng-events.c
@@ -210,8 +210,10 @@ void lttng_session_destroy(struct lttng_session *session)
                BUG_ON(chan->channel_type == METADATA_CHANNEL);
                _lttng_channel_destroy(chan);
        }
+       mutex_lock(&session->metadata_cache->lock);
        list_for_each_entry(metadata_stream, &session->metadata_cache->metadata_stream, list)
                _lttng_metadata_channel_hangup(metadata_stream);
+       mutex_unlock(&session->metadata_cache->lock);
        lttng_id_tracker_destroy(&session->pid_tracker, false);
        lttng_id_tracker_destroy(&session->vpid_tracker, false);
        lttng_id_tracker_destroy(&session->uid_tracker, false);
@@ -1696,9 +1698,9 @@ void lttng_metadata_end(struct lttng_session *session)
        if (atomic_dec_return(&session->metadata_cache->producing) == 0) {
                struct lttng_metadata_stream *stream;
 
-               mutex_unlock(&session->metadata_cache->lock);
                list_for_each_entry(stream, &session->metadata_cache->metadata_stream, list)
                        wake_up_interruptible(&stream->read_wait);
+               mutex_unlock(&session->metadata_cache->lock);
        }
 }
 
@@ -1717,7 +1719,7 @@ int lttng_metadata_printf(struct lttng_session *session,
        size_t len;
        va_list ap;
 
-       WARN_ON_ONCE(!READ_ONCE(session->active));
+       WARN_ON_ONCE(!LTTNG_READ_ONCE(session->active));
 
        va_start(ap, fmt);
        str = kvasprintf(GFP_KERNEL, fmt, ap);
@@ -2303,7 +2305,7 @@ int _lttng_event_metadata_statedump(struct lttng_session *session,
 {
        int ret = 0;
 
-       if (event->metadata_dumped || !READ_ONCE(session->active))
+       if (event->metadata_dumped || !LTTNG_READ_ONCE(session->active))
                return 0;
        if (chan->channel_type == METADATA_CHANNEL)
                return 0;
@@ -2375,7 +2377,7 @@ int _lttng_channel_metadata_statedump(struct lttng_session *session,
 {
        int ret = 0;
 
-       if (chan->metadata_dumped || !READ_ONCE(session->active))
+       if (chan->metadata_dumped || !LTTNG_READ_ONCE(session->active))
                return 0;
 
        if (chan->channel_type == METADATA_CHANNEL)
@@ -2602,7 +2604,7 @@ int _lttng_session_metadata_statedump(struct lttng_session *session)
        struct lttng_event *event;
        int ret = 0;
 
-       if (!READ_ONCE(session->active))
+       if (!LTTNG_READ_ONCE(session->active))
                return 0;
 
        lttng_metadata_begin(session);