X-Git-Url: https://git.lttng.org/?a=blobdiff_plain;f=src%2Fcommon%2Fkernel-consumer%2Fkernel-consumer.c;h=d2fda27b5d4dcbff1bc46217bc003144f50c33e6;hb=c0c85e4f64e24c5cf6709cf5b8b54c6c0aa13d66;hp=9fa92f6b80d190ff1d3202e03e8d9d8e110ff4ae;hpb=b2d8a465c1a12737e0ed4ec30f3bd59a5c39ca36;p=lttng-tools.git

diff --git a/src/common/kernel-consumer/kernel-consumer.c b/src/common/kernel-consumer/kernel-consumer.c
index 9fa92f6b8..d2fda27b5 100644
--- a/src/common/kernel-consumer/kernel-consumer.c
+++ b/src/common/kernel-consumer/kernel-consumer.c
@@ -17,6 +17,8 @@
  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  */
 
+#include "common/buffer-view.h"
+#include <stdint.h>
 #define _LGPL_SOURCE
 #include <assert.h>
 #include <poll.h>
@@ -123,6 +125,25 @@ int lttng_kconsumer_get_consumed_snapshot(struct lttng_consumer_stream *stream,
 	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 = stream->mmap_base;
+
+	ret = kernctl_get_mmap_read_offset(stream->wait_fd, &mmap_offset);
+	if (ret < 0) {
+		PERROR("Failed to get mmap read offset");
+		goto error;
+	}
+
+	*addr = mmap_base + mmap_offset;
+error:
+	return ret;
+}
+
 /*
  * Take a snapshot of all the stream of a channel
  * RCU read-side lock must be held across this function to ensure existence of
@@ -238,9 +259,10 @@ static int lttng_kconsumer_snapshot_channel(
 		while ((long) (consumed_pos - produced_pos) < 0) {
 			ssize_t read_len;
 			unsigned long len, padded_len;
+			const char *subbuf_addr;
+			struct lttng_buffer_view subbuf_view;
 
 			health_code_update();
-
 			DBG("Kernel consumer taking snapshot at pos %lu", consumed_pos);
 
 			ret = kernctl_get_subbuf(stream->wait_fd, &consumed_pos);
@@ -267,7 +289,15 @@ static int lttng_kconsumer_snapshot_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;
+			}
+
+			subbuf_view = lttng_buffer_view_init(
+					subbuf_addr, 0, padded_len);
+			read_len = lttng_consumer_on_read_subbuffer_mmap(ctx,
+					stream, &subbuf_view,
 					padded_len - len, NULL);
 			/*
 			 * We write the padded len in local tracefiles but the data len
@@ -634,7 +664,9 @@ int lttng_kconsumer_recv_cmd(struct lttng_consumer_local_data *ctx,
 		health_code_update();
 
 		pthread_mutex_lock(&channel->lock);
-		new_stream = consumer_allocate_stream(channel->key,
+		new_stream = consumer_allocate_stream(
+				channel,
+				channel->key,
 				fd,
 				channel->name,
 				channel->relayd_id,
@@ -656,7 +688,6 @@ int lttng_kconsumer_recv_cmd(struct lttng_consumer_local_data *ctx,
 			goto error_add_stream_nosignal;
 		}
 
-		new_stream->chan = channel;
 		new_stream->wait_fd = fd;
 		ret = kernctl_get_max_subbuf_size(new_stream->wait_fd,
 				&new_stream->max_sb_size);
@@ -1454,6 +1485,7 @@ int update_stream_stats(struct lttng_consumer_stream *stream)
 		if (ret == -ENOTTY) {
 			/* Command not implemented by lttng-modules. */
 			seq = -1ULL;
+			stream->sequence_number_unavailable = true;
 		} else {
 			PERROR("kernctl_get_sequence_number");
 			goto end;
@@ -1683,6 +1715,10 @@ ssize_t lttng_kconsumer_read_subbuffer(struct lttng_consumer_stream *stream,
 		}
 		break;
 	case CONSUMER_CHANNEL_MMAP:
+	{
+		const char *subbuf_addr;
+		struct lttng_buffer_view subbuf_view;
+
 		/* Get subbuffer size without padding */
 		err = kernctl_get_subbuf_size(infd, &subbuf_size);
 		if (err != 0) {
@@ -1702,18 +1738,25 @@ ssize_t lttng_kconsumer_read_subbuffer(struct lttng_consumer_stream *stream,
 			goto error;
 		}
 
+		ret = get_current_subbuf_addr(stream, &subbuf_addr);
+		if (ret) {
+			goto error_put_subbuf;
+		}
+
 		/* Make sure the tracer is not gone mad on us! */
 		assert(len >= subbuf_size);
 
 		padding = len - subbuf_size;
 
+		subbuf_view = lttng_buffer_view_init(subbuf_addr, 0, len);
+
 		/* 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_view, 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)) {
@@ -1728,11 +1771,12 @@ ssize_t lttng_kconsumer_read_subbuffer(struct lttng_consumer_stream *stream,
 			write_index = 0;
 		}
 		break;
+	}
 	default:
 		ERR("Unknown output method");
 		ret = -EPERM;
 	}
-
+error_put_subbuf:
 	err = kernctl_put_next_subbuf(infd);
 	if (err != 0) {
 		if (err == -EFAULT) {