From d771f8323f5f8964145e149502d6dc8d8cac8745 Mon Sep 17 00:00:00 2001 From: David Goulet Date: Fri, 28 Jun 2013 16:13:53 -0400 Subject: [PATCH] Fix: kernel snapshot metadata handling and error paths Signed-off-by: David Goulet --- src/common/kernel-consumer/kernel-consumer.c | 73 +++++++++++--------- 1 file changed, 40 insertions(+), 33 deletions(-) diff --git a/src/common/kernel-consumer/kernel-consumer.c b/src/common/kernel-consumer/kernel-consumer.c index ada5594b7..02198bd1b 100644 --- a/src/common/kernel-consumer/kernel-consumer.c +++ b/src/common/kernel-consumer/kernel-consumer.c @@ -363,9 +363,12 @@ end: int lttng_kconsumer_snapshot_metadata(uint64_t key, char *path, uint64_t relayd_id, struct lttng_consumer_local_data *ctx) { + int ret, use_relayd = 0; + ssize_t ret_read; struct lttng_consumer_channel *metadata_channel; struct lttng_consumer_stream *metadata_stream; - int ret; + + assert(ctx); DBG("Kernel consumer snapshot metadata with key %" PRIu64 " at path %s", key, path); @@ -374,58 +377,66 @@ int lttng_kconsumer_snapshot_metadata(uint64_t key, char *path, metadata_channel = consumer_find_channel(key); if (!metadata_channel) { - ERR("Snapshot kernel metadata channel not found for key %lu", key); + ERR("Kernel snapshot metadata not found for key %" PRIu64, key); ret = -1; - goto end; + goto error; } metadata_stream = metadata_channel->metadata_stream; assert(metadata_stream); + /* Flag once that we have a valid relayd for the stream. */ if (relayd_id != (uint64_t) -1ULL) { + use_relayd = 1; + } + + if (use_relayd) { ret = send_relayd_stream(metadata_stream, path); if (ret < 0) { - ERR("sending stream to relayd"); + goto error; } - DBG("Stream %s sent to the relayd", metadata_stream->name); } else { ret = utils_create_stream_file(path, metadata_stream->name, metadata_stream->chan->tracefile_size, metadata_stream->tracefile_count_current, metadata_stream->uid, metadata_stream->gid); if (ret < 0) { - goto end; + goto error; } metadata_stream->out_fd = ret; } - ret = 0; - while (ret >= 0) { - ret = lttng_kconsumer_read_subbuffer(metadata_stream, ctx); - if (ret < 0) { - if (ret != -EPERM) { - ERR("Kernel snapshot reading subbuffer"); - goto end; + do { + ret_read = lttng_kconsumer_read_subbuffer(metadata_stream, ctx); + if (ret_read < 0) { + if (ret_read != -EPERM) { + ERR("Kernel snapshot reading metadata subbuffer (ret: %ld)", + ret_read); + goto error; } - /* "ret" is negative at this point so we will exit the loop. */ + /* ret_read is negative at this point so we will exit the loop. */ continue; } - } + } while (ret_read >= 0); - if (relayd_id == (uint64_t) -1ULL) { + if (use_relayd) { + close_relayd_stream(metadata_stream); + metadata_stream->net_seq_idx = (uint64_t) -1ULL; + } else { ret = close(metadata_stream->out_fd); if (ret < 0) { - PERROR("Kernel consumer snapshot close out_fd"); - goto end; + PERROR("Kernel consumer snapshot metadata close out_fd"); + /* + * Don't go on error here since the snapshot was successful at this + * point but somehow the close failed. + */ } metadata_stream->out_fd = -1; - } else { - close_relayd_stream(metadata_stream); - metadata_stream->net_seq_idx = (uint64_t) -1ULL; } ret = 0; -end: + +error: rcu_read_unlock(); return ret; } @@ -568,20 +579,15 @@ int lttng_kconsumer_recv_cmd(struct lttng_consumer_local_data *ctx, /* First send a status message before receiving the fds. */ ret = consumer_send_status_msg(sock, ret_code); if (ret < 0) { - /* - * Somehow, the session daemon is not responding - * anymore. - */ + /* Somehow, the session daemon is not responding anymore. */ goto error_fatal; } if (ret_code != LTTNG_OK) { - /* - * Channel was not found. - */ + /* Channel was not found. */ goto end_nosignal; } - /* block */ + /* Blocking call */ if (lttng_consumer_poll_socket(consumer_sockpoll) < 0) { rcu_read_unlock(); return -EINTR; @@ -627,6 +633,7 @@ int lttng_kconsumer_recv_cmd(struct lttng_consumer_local_data *ctx, } goto end_nosignal; } + new_stream->chan = channel; new_stream->wait_fd = fd; switch (channel->output) { @@ -664,7 +671,7 @@ int lttng_kconsumer_recv_cmd(struct lttng_consumer_local_data *ctx, if (ctx->on_recv_stream) { ret = ctx->on_recv_stream(new_stream); if (ret < 0) { - consumer_del_stream(new_stream, NULL); + consumer_stream_free(new_stream); goto end_nosignal; } } @@ -685,7 +692,7 @@ int lttng_kconsumer_recv_cmd(struct lttng_consumer_local_data *ctx, ret = send_relayd_stream(new_stream, NULL); if (ret < 0) { - consumer_del_stream(new_stream, NULL); + consumer_stream_free(new_stream); goto end_nosignal; } @@ -701,7 +708,7 @@ int lttng_kconsumer_recv_cmd(struct lttng_consumer_local_data *ctx, ERR("Consumer write %s stream to pipe %d", new_stream->metadata_flag ? "metadata" : "data", lttng_pipe_get_writefd(stream_pipe)); - consumer_del_stream(new_stream, NULL); + consumer_stream_free(new_stream); goto end_nosignal; } -- 2.34.1