consumerd: tag metadata channel as being part of a live session

[lttng-tools.git] / src / common / kernel-consumer / kernel-consumer.c

diff --git a/src/common/kernel-consumer/kernel-consumer.c b/src/common/kernel-consumer/kernel-consumer.c
index c5c87cc9e12ff191337c2e40283ca7a860193a26..7032a7f7ffcc9bea224db0c6059f1928de72aa47 100644 (file)
--- a/src/common/kernel-consumer/kernel-consumer.c
+++ b/src/common/kernel-consumer/kernel-consumer.c
@@ -1,22 +1,14 @@
 /*
- * Copyright (C) 2011 - Julien Desfossez <julien.desfossez@polymtl.ca>
- *                      Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
- * Copyright (C) 2017 - Jérémie Galarneau <jeremie.galarneau@efficios.com>
+ * Copyright (C) 2011 Julien Desfossez <julien.desfossez@polymtl.ca>
+ * Copyright (C) 2011 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
+ * Copyright (C) 2017 Jérémie Galarneau <jeremie.galarneau@efficios.com>
  *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License, version 2 only,
- * as published by the Free Software Foundation.
+ * SPDX-License-Identifier: GPL-2.0-only
  *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License along
- * with this program; if not, write to the Free Software Foundation, Inc.,
- * 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 +115,25 @@ 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 +249,10 @@ 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 +279,15 @@ 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
@@ -493,6 +513,7 @@ int lttng_kconsumer_recv_cmd(struct lttng_consumer_local_data *ctx,
                                msg.u.channel.tracefile_count, 0,
                                msg.u.channel.monitor,
                                msg.u.channel.live_timer_interval,
+                               msg.u.channel.is_live,
                                NULL, NULL);
                if (new_channel == NULL) {
                        lttng_consumer_send_error(ctx, LTTCOMM_CONSUMERD_OUTFD_ERROR);
@@ -634,7 +655,9 @@ 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 +679,6 @@ 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);
@@ -1701,6 +1723,10 @@ 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) {
@@ -1720,18 +1746,25 @@ 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)) {
@@ -1746,11 +1779,12 @@ 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) {