X-Git-Url: http://git.liburcu.org/?a=blobdiff_plain;f=src%2Fcommon%2Fust-consumer%2Fust-consumer.c;h=0e24f8c8c73053f58c85439f788049567938b599;hb=7775df526447e504735983ee359dcb902fa6dd1e;hp=f8706d0ba88528e3dbf1e698de96eec9c4d5073d;hpb=6564a2b67783df036aa7cb389ebfdcc18504c69a;p=lttng-tools.git diff --git a/src/common/ust-consumer/ust-consumer.c b/src/common/ust-consumer/ust-consumer.c index f8706d0ba..0e24f8c8c 100644 --- a/src/common/ust-consumer/ust-consumer.c +++ b/src/common/ust-consumer/ust-consumer.c @@ -17,6 +17,7 @@ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. */ +#include #define _LGPL_SOURCE #include #include @@ -1088,6 +1089,35 @@ error: return ret; } +static +int get_current_subbuf_addr(struct lttng_consumer_stream *stream, + const char **addr) +{ + int ret; + unsigned long mmap_offset; + const char *mmap_base; + + mmap_base = ustctl_get_mmap_base(stream->ustream); + if (!mmap_base) { + ERR("Failed to get mmap base for stream `%s`", + stream->name); + ret = -EPERM; + goto error; + } + + ret = ustctl_get_mmap_read_offset(stream->ustream, &mmap_offset); + if (ret != 0) { + ERR("Failed to get mmap offset for stream `%s`", stream->name); + ret = -EINVAL; + goto error; + } + + *addr = mmap_base + mmap_offset; +error: + return ret; + +} + /* * Take a snapshot of all the stream of a channel. * RCU read-side lock and the channel lock must be held by the caller. @@ -1190,6 +1220,7 @@ static int snapshot_channel(struct lttng_consumer_channel *channel, while ((long) (consumed_pos - produced_pos) < 0) { ssize_t read_len; unsigned long len, padded_len; + const char *subbuf_addr; health_code_update(); @@ -1219,7 +1250,13 @@ static int snapshot_channel(struct lttng_consumer_channel *channel, goto error_put_subbuf; } - read_len = lttng_consumer_on_read_subbuffer_mmap(ctx, stream, len, + ret = get_current_subbuf_addr(stream, &subbuf_addr); + if (ret) { + goto error_put_subbuf; + } + + read_len = lttng_consumer_on_read_subbuffer_mmap(ctx, + stream, subbuf_addr, len, padded_len - len, NULL); if (use_relayd) { if (read_len != len) { @@ -2170,7 +2207,6 @@ end_msg_sessiond: end_channel_error: if (channel) { - pthread_mutex_unlock(&channel->lock); /* * Free channel here since no one has a reference to it. We don't * free after that because a stream can store this pointer. @@ -2197,31 +2233,6 @@ end: return ret; } -/* - * Wrapper over the mmap() read offset from ust-ctl library. Since this can be - * compiled out, we isolate it in this library. - */ -int lttng_ustctl_get_mmap_read_offset(struct lttng_consumer_stream *stream, - unsigned long *off) -{ - assert(stream); - assert(stream->ustream); - - return ustctl_get_mmap_read_offset(stream->ustream, off); -} - -/* - * Wrapper over the mmap() read offset from ust-ctl library. Since this can be - * compiled out, we isolate it in this library. - */ -void *lttng_ustctl_get_mmap_base(struct lttng_consumer_stream *stream) -{ - assert(stream); - assert(stream->ustream); - - return ustctl_get_mmap_base(stream->ustream); -} - void lttng_ustctl_flush_buffer(struct lttng_consumer_stream *stream, int producer_active) { @@ -2583,37 +2594,59 @@ end: * interacting with sessiond, else we cause a deadlock with live * awaiting on metadata to be pushed out. * + * The RCU read side lock must be held by the caller. + * * Return 0 if new metadatda is available, EAGAIN if the metadata stream * is empty or a negative value on error. */ int lttng_ustconsumer_sync_metadata(struct lttng_consumer_local_data *ctx, - struct lttng_consumer_stream *metadata) + struct lttng_consumer_stream *metadata_stream) { int ret; int retry = 0; + struct lttng_consumer_channel *metadata_channel; assert(ctx); - assert(metadata); + assert(metadata_stream); - pthread_mutex_unlock(&metadata->lock); + metadata_channel = metadata_stream->chan; + pthread_mutex_unlock(&metadata_stream->lock); /* * Request metadata from the sessiond, but don't wait for the flush * because we locked the metadata thread. */ - ret = lttng_ustconsumer_request_metadata(ctx, metadata->chan, 0, 0); - pthread_mutex_lock(&metadata->lock); + ret = lttng_ustconsumer_request_metadata(ctx, metadata_channel, 0, 0); + pthread_mutex_lock(&metadata_stream->lock); if (ret < 0) { goto end; } - ret = commit_one_metadata_packet(metadata); + /* + * The metadata stream and channel can be deleted while the + * metadata stream lock was released. The streamed is checked + * for deletion before we use it further. + * + * Note that it is safe to access a logically-deleted stream since its + * existence is still guaranteed by the RCU read side lock. However, + * it should no longer be used. The close/deletion of the metadata + * channel and stream already guarantees that all metadata has been + * consumed. Therefore, there is nothing left to do in this function. + */ + if (consumer_stream_is_deleted(metadata_stream)) { + DBG("Metadata stream %" PRIu64 " was deleted during the metadata synchronization", + metadata_stream->key); + ret = 0; + goto end; + } + + ret = commit_one_metadata_packet(metadata_stream); if (ret <= 0) { goto end; } else if (ret > 0) { retry = 1; } - ret = ustctl_snapshot(metadata->ustream); + ret = ustctl_snapshot(metadata_stream->ustream); if (ret < 0) { if (errno != EAGAIN) { ERR("Sync metadata, taking UST snapshot"); @@ -2757,6 +2790,7 @@ int lttng_ustconsumer_read_subbuffer(struct lttng_consumer_stream *stream, long ret = 0; struct ustctl_consumer_stream *ustream; struct ctf_packet_index index; + const char *subbuf_addr; assert(stream); assert(stream->ustream); @@ -2866,11 +2900,19 @@ retry: padding = len - subbuf_size; + ret = get_current_subbuf_addr(stream, &subbuf_addr); + if (ret) { + write_index = 0; + goto error_put_subbuf; + } + /* write the subbuffer to the tracefile */ - ret = lttng_consumer_on_read_subbuffer_mmap(ctx, stream, subbuf_size, padding, &index); + ret = lttng_consumer_on_read_subbuffer_mmap( + ctx, stream, subbuf_addr, subbuf_size, padding, &index); /* - * The mmap operation should write subbuf_size amount of data when network - * streaming or the full padding (len) size when we are _not_ streaming. + * The mmap operation should write subbuf_size amount of data when + * network streaming or the full padding (len) size when we are _not_ + * streaming. */ if ((ret != subbuf_size && stream->net_seq_idx != (uint64_t) -1ULL) || (ret != len && stream->net_seq_idx == (uint64_t) -1ULL)) { @@ -2887,6 +2929,7 @@ retry: ret, len, subbuf_size); write_index = 0; } +error_put_subbuf: err = ustctl_put_next_subbuf(ustream); assert(err == 0);