Fix: x86 kvm mmutrace instrumentation for kernel < 3.6

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

diff --git a/lttng-abi.c b/lttng-abi.c
index 5823a1db042d6fa8aa5e88bef4a35235bf5eea4e..bdc6c7660601761bc42b999a3e99b5515916e6e2 100644 (file)
--- a/lttng-abi.c
+++ b/lttng-abi.c
@@ -565,9 +565,11 @@ unsigned int lttng_metadata_ring_buffer_poll(struct file *filp,
                if (finalized)
                        mask |= POLLHUP;
 
+               mutex_lock(&stream->metadata_cache->lock);
                if (stream->metadata_cache->metadata_written >
                                stream->metadata_out)
                        mask |= POLLIN;
+               mutex_unlock(&stream->metadata_cache->lock);
        }
 
        return mask;
@@ -865,7 +867,6 @@ int lttng_abi_open_metadata_stream(struct file *channel_file)
        metadata_stream->priv = buf;
        stream_priv = metadata_stream;
        metadata_stream->transport = channel->transport;
-       mutex_init(&metadata_stream->lock);
 
        /*
         * Since life-time of metadata cache differs from that of
@@ -1233,8 +1234,8 @@ int lttng_metadata_channel_release(struct inode *inode, struct file *file)
        struct lttng_channel *channel = file->private_data;
 
        if (channel) {
-               lttng_metadata_channel_destroy(channel);
                fput(channel->session->file);
+               lttng_metadata_channel_destroy(channel);
        }
 
        return 0;