#include "kernel-consumer.h"
#include "kern-modules.h"
#include "utils.h"
+#include "rotate.h"
+
+/*
+ * Key used to reference a channel between the sessiond and the consumer. This
+ * is only read and updated with the session_list lock held.
+ */
+static uint64_t next_kernel_channel_key;
/*
* Add context on a kernel channel.
end:
cds_list_add_tail(&ctx->list, &chan->ctx_list);
+ ctx->in_list = true;
ctx = NULL;
error:
if (ctx) {
cds_list_add(&lkc->list, &session->channel_list.head);
session->channel_count++;
lkc->session = session;
+ lkc->key = ++next_kernel_channel_key;
- DBG("Kernel channel %s created (fd: %d)", lkc->channel->name, lkc->fd);
+ DBG("Kernel channel %s created (fd: %d, key: %" PRIu64 ")",
+ lkc->channel->name, lkc->fd, lkc->key);
return 0;
}
chan->enabled = 0;
- DBG("Kernel channel %s disabled (fd: %d)", chan->channel->name, chan->fd);
+ DBG("Kernel channel %s disabled (fd: %d, key: %" PRIu64 ")",
+ chan->channel->name, chan->fd, chan->key);
return 0;
}
chan->enabled = 1;
- DBG("Kernel channel %s enabled (fd: %d)", chan->channel->name, chan->fd);
+ DBG("Kernel channel %s enabled (fd: %d, key: %" PRIu64 ")",
+ chan->channel->name, chan->fd, chan->key);
return 0;
}
lkm->fd = ret;
+ lkm->key = ++next_kernel_channel_key;
/* Prevent fd duplication after execlp() */
ret = fcntl(lkm->fd, F_SETFD, FD_CLOEXEC);
if (ret < 0) {
/*
* Get kernel version and validate it.
*/
-int kernel_validate_version(int tracer_fd)
+int kernel_validate_version(int tracer_fd,
+ struct lttng_kernel_tracer_version *version,
+ struct lttng_kernel_tracer_abi_version *abi_version)
{
int ret;
- struct lttng_kernel_tracer_version version;
- struct lttng_kernel_tracer_abi_version abi_version;
- ret = kernctl_tracer_version(tracer_fd, &version);
+ ret = kernctl_tracer_version(tracer_fd, version);
if (ret < 0) {
ERR("Failed to retrieve the lttng-modules version");
goto error;
}
/* Validate version */
- if (version.major != VERSION_MAJOR) {
+ if (version->major != VERSION_MAJOR) {
ERR("Kernel tracer major version (%d) is not compatible with lttng-tools major version (%d)",
- version.major, VERSION_MAJOR);
+ version->major, VERSION_MAJOR);
goto error_version;
}
- ret = kernctl_tracer_abi_version(tracer_fd, &abi_version);
+ ret = kernctl_tracer_abi_version(tracer_fd, abi_version);
if (ret < 0) {
ERR("Failed to retrieve lttng-modules ABI version");
goto error;
}
- if (abi_version.major != LTTNG_MODULES_ABI_MAJOR_VERSION) {
+ if (abi_version->major != LTTNG_MODULES_ABI_MAJOR_VERSION) {
ERR("Kernel tracer ABI version (%d.%d) does not match the expected ABI major version (%d.*)",
- abi_version.major, abi_version.minor,
+ abi_version->major, abi_version->minor,
LTTNG_MODULES_ABI_MAJOR_VERSION);
goto error;
}
DBG2("Kernel tracer version validated (%d.%d, ABI %d.%d)",
- version.major, version.minor,
- abi_version.major, abi_version.minor);
+ version->major, version->minor,
+ abi_version->major, abi_version->minor);
return 0;
error_version:
/* For each channel, ask the consumer to snapshot it. */
cds_list_for_each_entry(chan, &ksess->channel_list.head, list) {
- pthread_mutex_lock(socket->lock);
- ret = consumer_snapshot_channel(socket, chan->fd, output, 0,
+ ret = consumer_snapshot_channel(socket, chan->key, output, 0,
ksess->uid, ksess->gid,
DEFAULT_KERNEL_TRACE_DIR, wait,
nb_packets_per_stream);
- pthread_mutex_unlock(socket->lock);
if (ret < 0) {
ret = LTTNG_ERR_KERN_CONSUMER_FAIL;
(void) kernel_consumer_destroy_metadata(socket,
}
/* Snapshot metadata, */
- pthread_mutex_lock(socket->lock);
- ret = consumer_snapshot_channel(socket, ksess->metadata->fd, output,
+ ret = consumer_snapshot_channel(socket, ksess->metadata->key, output,
1, ksess->uid, ksess->gid,
DEFAULT_KERNEL_TRACE_DIR, wait, 0);
- pthread_mutex_unlock(socket->lock);
if (ret < 0) {
ret = LTTNG_ERR_KERN_CONSUMER_FAIL;
goto error_consumer;
error:
return ret;
}
+
+/*
+ * Rotate a kernel session.
+ *
+ * Return 0 on success or else return a LTTNG_ERR code.
+ */
+int kernel_rotate_session(struct ltt_session *session)
+{
+ int ret;
+ struct consumer_socket *socket;
+ struct lttng_ht_iter iter;
+ struct ltt_kernel_session *ksess = session->kernel_session;
+
+ assert(ksess);
+ assert(ksess->consumer);
+
+ DBG("Rotate kernel session %s started (session %" PRIu64 ")",
+ session->name, session->id);
+
+ rcu_read_lock();
+
+ /*
+ * Note that this loop will end after one iteration given that there is
+ * only one kernel consumer.
+ */
+ cds_lfht_for_each_entry(ksess->consumer->socks->ht, &iter.iter,
+ socket, node.node) {
+ struct ltt_kernel_channel *chan;
+
+ /*
+ * Account the metadata channel first to make sure the
+ * number of channels waiting for a rotation cannot
+ * reach 0 before we complete the iteration over all
+ * the channels.
+ */
+ ret = rotate_add_channel_pending(ksess->metadata->key,
+ LTTNG_DOMAIN_KERNEL, session);
+ if (ret < 0) {
+ ret = LTTNG_ERR_KERN_CONSUMER_FAIL;
+ goto error;
+ }
+
+ /* For each channel, ask the consumer to rotate it. */
+ cds_list_for_each_entry(chan, &ksess->channel_list.head, list) {
+ ret = rotate_add_channel_pending(chan->key,
+ LTTNG_DOMAIN_KERNEL, session);
+ if (ret < 0) {
+ ret = LTTNG_ERR_KERN_CONSUMER_FAIL;
+ goto error;
+ }
+
+ DBG("Rotate channel %" PRIu64 ", session %s", chan->key, session->name);
+ ret = consumer_rotate_channel(socket, chan->key,
+ ksess->uid, ksess->gid, ksess->consumer,
+ ksess->consumer->subdir,
+ /* is_metadata_channel */ false,
+ session->current_archive_id,
+ &session->rotate_pending_relay);
+ if (ret < 0) {
+ ret = LTTNG_ERR_KERN_CONSUMER_FAIL;
+ goto error;
+ }
+ }
+
+ /*
+ * Rotate the metadata channel.
+ */
+ ret = consumer_rotate_channel(socket, ksess->metadata->key,
+ ksess->uid, ksess->gid, ksess->consumer,
+ ksess->consumer->subdir,
+ /* is_metadata_channel */ true,
+ session->current_archive_id,
+ &session->rotate_pending_relay);
+ if (ret < 0) {
+ ret = LTTNG_ERR_KERN_CONSUMER_FAIL;
+ goto error;
+ }
+ }
+
+ ret = LTTNG_OK;
+
+error:
+ rcu_read_unlock();
+ return ret;
+}