Common consumer functions to read current positions

Introduce lttng_consumer_sample_snapshot_positions and
lttng_consumer_get_consumed_snapshotconsumer_flush_buffer to take a
snapshot of the positions and read the consumed position.

Signed-off-by: Julien Desfossez <jdesfossez@efficios.com>
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

diff --git a/src/common/consumer/consumer.c b/src/common/consumer/consumer.c
index 2fa65f4d4e53666e18b0278cea052b20177a6158..07de6757849f5a01e4c19d4bde771cca11ffe462 100644 (file)
--- a/src/common/consumer/consumer.c
+++ b/src/common/consumer/consumer.c
@@ -1971,6 +1971,25 @@ end:
        return written;
 }
 
+/*
+ * Sample the snapshot positions for a specific fd
+ *
+ * Returns 0 on success, < 0 on error
+ */
+int lttng_consumer_sample_snapshot_positions(struct lttng_consumer_stream *stream)
+{
+       switch (consumer_data.type) {
+       case LTTNG_CONSUMER_KERNEL:
+               return lttng_kconsumer_sample_snapshot_positions(stream);
+       case LTTNG_CONSUMER32_UST:
+       case LTTNG_CONSUMER64_UST:
+               return lttng_ustconsumer_sample_snapshot_positions(stream);
+       default:
+               ERR("Unknown consumer_data type");
+               assert(0);
+               return -ENOSYS;
+       }
+}
 /*
  * Take a snapshot for a specific fd
  *
@@ -2012,6 +2031,27 @@ int lttng_consumer_get_produced_snapshot(struct lttng_consumer_stream *stream,
        }
 }
 
+/*
+ * Get the consumed position (free-running counter position in bytes).
+ *
+ * Returns 0 on success, < 0 on error
+ */
+int lttng_consumer_get_consumed_snapshot(struct lttng_consumer_stream *stream,
+               unsigned long *pos)
+{
+       switch (consumer_data.type) {
+       case LTTNG_CONSUMER_KERNEL:
+               return lttng_kconsumer_get_consumed_snapshot(stream, pos);
+       case LTTNG_CONSUMER32_UST:
+       case LTTNG_CONSUMER64_UST:
+               return lttng_ustconsumer_get_consumed_snapshot(stream, pos);
+       default:
+               ERR("Unknown consumer_data type");
+               assert(0);
+               return -ENOSYS;
+       }
+}
+
 int lttng_consumer_recv_cmd(struct lttng_consumer_local_data *ctx,
                int sock, struct pollfd *consumer_sockpoll)
 {

diff --git a/src/common/consumer/consumer.h b/src/common/consumer/consumer.h
index a7d0ee1a706cc719f6877b168a6819f97f72b0ac..8a780e7f835eb49abd721c027e4c6f1dc6df9a54 100644 (file)
--- a/src/common/consumer/consumer.h
+++ b/src/common/consumer/consumer.h
@@ -744,9 +744,12 @@ ssize_t lttng_consumer_on_read_subbuffer_splice(
                struct lttng_consumer_stream *stream, unsigned long len,
                unsigned long padding,
                struct ctf_packet_index *index);
+int lttng_consumer_sample_snapshot_positions(struct lttng_consumer_stream *stream);
 int lttng_consumer_take_snapshot(struct lttng_consumer_stream *stream);
 int lttng_consumer_get_produced_snapshot(struct lttng_consumer_stream *stream,
                unsigned long *pos);
+int lttng_consumer_get_consumed_snapshot(struct lttng_consumer_stream *stream,
+               unsigned long *pos);
 int lttng_ustconsumer_get_wakeup_fd(struct lttng_consumer_stream *stream);
 int lttng_ustconsumer_close_wakeup_fd(struct lttng_consumer_stream *stream);
 void *consumer_thread_metadata_poll(void *data);