X-Git-Url: http://git.lttng.org./?a=blobdiff_plain;f=ltt-ring-buffer-client.h;h=904c42eb466b68e8745f1108ad50922460ba4980;hb=fcf745787bc83653284a78ff9846f2d75ca35a65;hp=6389c98d5fc18f30307b216ae300edfeacbfd59c;hpb=5fe87d9b7e8ad3b11a1841c630865afdd1cd1946;p=lttng-modules.git

diff --git a/ltt-ring-buffer-client.h b/ltt-ring-buffer-client.h
index 6389c98d..904c42eb 100644
--- a/ltt-ring-buffer-client.h
+++ b/ltt-ring-buffer-client.h
@@ -22,6 +22,14 @@
  * you ever add/remove a field from this header. Packed attribute is not used
  * because gcc generates poor code on at least powerpc and mips. Don't ever
  * let gcc add padding between the structure elements.
+ *
+ * The guarantee we have with timestamps is that all the events in a
+ * packet are included (inclusive) within the begin/end timestamps of
+ * the packet. Another guarantee we have is that the "timestamp begin",
+ * as well as the event timestamps, are monotonically increasing (never
+ * decrease) when moving forward in a stream (physically). But this
+ * guarantee does not apply to "timestamp end", because it is sampled at
+ * commit time, which is not ordered with respect to space reservation.
  */
 
 struct packet_header {
@@ -137,6 +145,7 @@ unsigned char record_header_size(const struct lib_ring_buffer_config *config,
 		}
 		break;
 	default:
+		padding = 0;
 		WARN_ON_ONCE(1);
 	}
 	offset += ctx_get_size(offset, event->ctx);
@@ -148,7 +157,7 @@ unsigned char record_header_size(const struct lib_ring_buffer_config *config,
 
 #include "wrapper/ringbuffer/api.h"
 
-extern
+static
 void ltt_write_event_header_slow(const struct lib_ring_buffer_config *config,
 				 struct lib_ring_buffer_ctx *ctx,
 				 uint32_t event_id);
@@ -197,8 +206,8 @@ void ltt_write_event_header(const struct lib_ring_buffer_config *config,
 		WARN_ON_ONCE(1);
 	}
 
-	ctx_record(ctx, ltt_chan, event->ctx);
 	ctx_record(ctx, ltt_chan, ltt_chan->ctx);
+	ctx_record(ctx, ltt_chan, event->ctx);
 
 	return;
 
@@ -206,6 +215,7 @@ slow_path:
 	ltt_write_event_header_slow(config, ctx, event_id);
 }
 
+static
 void ltt_write_event_header_slow(const struct lib_ring_buffer_config *config,
 				 struct lib_ring_buffer_ctx *ctx,
 				 uint32_t event_id)
@@ -259,8 +269,8 @@ void ltt_write_event_header_slow(const struct lib_ring_buffer_config *config,
 	default:
 		WARN_ON_ONCE(1);
 	}
-	ctx_record(ctx, ltt_chan, event->ctx);
 	ctx_record(ctx, ltt_chan, ltt_chan->ctx);
+	ctx_record(ctx, ltt_chan, event->ctx);
 }
 
 static const struct lib_ring_buffer_config client_config;
@@ -361,7 +371,7 @@ static const struct lib_ring_buffer_config client_config = {
 	.sync = RING_BUFFER_SYNC_PER_CPU,
 	.mode = RING_BUFFER_MODE_TEMPLATE,
 	.backend = RING_BUFFER_PAGE,
-	.output = RING_BUFFER_SPLICE,
+	.output = RING_BUFFER_OUTPUT_TEMPLATE,
 	.oops = RING_BUFFER_OOPS_CONSISTENCY,
 	.ipi = RING_BUFFER_IPI_BARRIER,
 	.wakeup = RING_BUFFER_WAKEUP_BY_TIMER,
@@ -399,6 +409,20 @@ struct lib_ring_buffer *ltt_buffer_read_open(struct channel *chan)
 	return NULL;
 }
 
+static
+int ltt_buffer_has_read_closed_stream(struct channel *chan)
+{
+	struct lib_ring_buffer *buf;
+	int cpu;
+
+	for_each_channel_cpu(cpu, chan) {
+		buf = channel_get_ring_buffer(&client_config, chan, cpu);
+		if (!atomic_long_read(&buf->active_readers))
+			return 1;
+	}
+	return 0;
+}
+
 static
 void ltt_buffer_read_close(struct lib_ring_buffer *buf)
 {
@@ -485,6 +509,8 @@ static struct ltt_transport ltt_relay_transport = {
 		.channel_create = _channel_create,
 		.channel_destroy = ltt_channel_destroy,
 		.buffer_read_open = ltt_buffer_read_open,
+		.buffer_has_read_closed_stream =
+			ltt_buffer_has_read_closed_stream,
 		.buffer_read_close = ltt_buffer_read_close,
 		.event_reserve = ltt_event_reserve,
 		.event_commit = ltt_event_commit,