X-Git-Url: https://git.liburcu.org/?a=blobdiff_plain;f=src%2Fbin%2Flttng-sessiond%2Frotate.c;fp=src%2Fbin%2Flttng-sessiond%2Frotate.c;h=05e9bb08a48ca397710beb720c78ea5e59891df4;hb=db66e57489e5014289dc1d831e1eac90ac4fc0da;hp=0000000000000000000000000000000000000000;hpb=b99a8d4211e26a847ca8916884354f159c999ad2;p=lttng-tools.git

diff --git a/src/bin/lttng-sessiond/rotate.c b/src/bin/lttng-sessiond/rotate.c
new file mode 100644
index 000000000..05e9bb08a
--- /dev/null
+++ b/src/bin/lttng-sessiond/rotate.c
@@ -0,0 +1,320 @@
+/*
+ * Copyright (C) 2017 - Julien Desfossez <jdesfossez@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.
+ *
+ * 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.
+ */
+
+#define _LGPL_SOURCE
+#include <lttng/trigger/trigger.h>
+#include <common/error.h>
+#include <common/config/session-config.h>
+#include <common/defaults.h>
+#include <common/utils.h>
+#include <common/futex.h>
+#include <common/align.h>
+#include <common/time.h>
+#include <common/hashtable/utils.h>
+#include <common/kernel-ctl/kernel-ctl.h>
+#include <sys/eventfd.h>
+#include <sys/stat.h>
+#include <time.h>
+#include <signal.h>
+#include <inttypes.h>
+
+#include "session.h"
+#include "rotate.h"
+#include "rotation-thread.h"
+#include "lttng-sessiond.h"
+#include "health-sessiond.h"
+#include "cmd.h"
+#include "utils.h"
+
+#include <urcu.h>
+#include <urcu/list.h>
+#include <urcu/rculfhash.h>
+
+unsigned long hash_channel_key(struct rotation_channel_key *key)
+{
+	return hash_key_u64(&key->key, lttng_ht_seed) ^ hash_key_ulong(
+			(void *) (unsigned long) key->domain, lttng_ht_seed);
+}
+
+/* The session's lock must be held by the caller. */
+static
+int session_rename_chunk(struct ltt_session *session, char *current_path,
+		char *new_path)
+{
+	int ret;
+	struct consumer_socket *socket;
+	struct consumer_output *output;
+	struct lttng_ht_iter iter;
+	uid_t uid;
+	gid_t gid;
+
+	DBG("Renaming session chunk path of session \"%s\" from %s to %s",
+			session->name, current_path, new_path);
+
+	/*
+	 * Either one of the sessions is enough to find the consumer_output
+	 * and uid/gid.
+	 */
+	if (session->kernel_session) {
+		output = session->kernel_session->consumer;
+		uid = session->kernel_session->uid;
+		gid = session->kernel_session->gid;
+	} else if (session->ust_session) {
+		output = session->ust_session->consumer;
+		uid = session->ust_session->uid;
+		gid = session->ust_session->gid;
+	} else {
+		assert(0);
+	}
+
+	if (!output || !output->socks) {
+		ERR("No consumer output found for session \"%s\"",
+				session->name);
+		ret = -1;
+		goto end;
+	}
+
+	rcu_read_lock();
+	/*
+	 * We have to iterate to find a socket, but we only need to send the
+	 * rename command to one consumer, so we break after the first one.
+	 */
+	cds_lfht_for_each_entry(output->socks->ht, &iter.iter, socket, node.node) {
+		pthread_mutex_lock(socket->lock);
+		ret = consumer_rotate_rename(socket, session->id, output,
+				current_path, new_path, uid, gid);
+		pthread_mutex_unlock(socket->lock);
+		if (ret) {
+			ret = -1;
+			goto end_unlock;
+		}
+		break;
+	}
+
+	ret = 0;
+
+end_unlock:
+	rcu_read_unlock();
+end:
+	return ret;
+}
+
+/* The session's lock must be held by the caller. */
+static
+int rename_first_chunk(struct ltt_session *session,
+		struct consumer_output *consumer, char *new_path)
+{
+	int ret;
+	char current_full_path[LTTNG_PATH_MAX], new_full_path[LTTNG_PATH_MAX];
+
+	/* Current domain path: <session>/kernel */
+	if (session->net_handle > 0) {
+		ret = snprintf(current_full_path, sizeof(current_full_path), "%s/%s",
+				consumer->dst.net.base_dir, consumer->subdir);
+		if (ret < 0 || ret >= sizeof(current_full_path)) {
+			ERR("Failed to initialize current full path while renaming first rotation chunk of session \"%s\"",
+					session->name);
+			ret = -1;
+			goto error;
+		}
+	} else {
+		ret = snprintf(current_full_path, sizeof(current_full_path), "%s/%s",
+				consumer->dst.session_root_path, consumer->subdir);
+		if (ret < 0 || ret >= sizeof(current_full_path)) {
+			ERR("Failed to initialize current full path while renaming first rotation chunk of session \"%s\"",
+					session->name);
+			ret = -1;
+			goto error;
+		}
+	}
+	/* New domain path: <session>/<start-date>-<end-date>-<rotate-count>/kernel */
+	ret = snprintf(new_full_path, sizeof(new_full_path), "%s/%s",
+			new_path, consumer->subdir);
+	if (ret < 0 || ret >= sizeof(new_full_path)) {
+		ERR("Failed to initialize new full path while renaming first rotation chunk of session \"%s\"",
+				session->name);
+		ret = -1;
+		goto error;
+	}
+	/*
+	 * Move the per-domain fcurrenter inside the first rotation
+	 * fcurrenter.
+	 */
+	ret = session_rename_chunk(session, current_full_path, new_full_path);
+	if (ret < 0) {
+		ret = -LTTNG_ERR_UNK;
+		goto error;
+	}
+
+	ret = 0;
+
+error:
+	return ret;
+}
+
+/*
+ * Rename a chunk folder after a rotation is complete.
+ * session_lock_list and session lock must be held.
+ *
+ * Returns 0 on success, a negative value on error.
+ */
+int rename_complete_chunk(struct ltt_session *session, time_t ts)
+{
+	struct tm *timeinfo;
+	char datetime[16], start_datetime[16];
+	char new_path[LTTNG_PATH_MAX];
+	int ret;
+	size_t strf_ret;
+
+	DBG("Renaming completed chunk for session %s", session->name);
+	timeinfo = localtime(&ts);
+	if (!timeinfo) {
+		ERR("Failed to retrieve local time while renaming completed chunk");
+		ret = -1;
+		goto end;
+	}
+	strf_ret = strftime(datetime, sizeof(datetime), "%Y%m%d-%H%M%S",
+			timeinfo);
+	if (strf_ret == 0) {
+		ERR("Failed to format timestamp while renaming completed session chunk");
+		ret = -1;
+		goto end;
+	}
+
+	if (session->rotate_count == 1) {
+		char start_time[16];
+
+		timeinfo = localtime(&session->last_chunk_start_ts);
+		if (!timeinfo) {
+			ERR("Failed to retrieve local time while renaming completed chunk");
+			ret = -1;
+			goto end;
+		}
+
+		strf_ret = strftime(start_time, sizeof(start_time),
+				"%Y%m%d-%H%M%S", timeinfo);
+		if (strf_ret == 0) {
+			ERR("Failed to format timestamp while renaming completed session chunk");
+			ret = -1;
+			goto end;
+		}
+
+		/*
+		 * On the first rotation, the current_rotate_path is the
+		 * session_root_path, so we need to create the chunk folder
+		 * and move the domain-specific folders inside it.
+		 */
+		ret = snprintf(new_path, sizeof(new_path), "%s/%s-%s-%" PRIu64,
+				session->rotation_chunk.current_rotate_path,
+				start_time,
+				datetime, session->rotate_count);
+		if (ret < 0 || ret >= sizeof(new_path)) {
+			ERR("Failed to format new chunk path while renaming session \"%s\"'s first chunk",
+					session->name);
+			ret = -1;
+			goto end;
+		}
+
+		if (session->kernel_session) {
+			ret = rename_first_chunk(session,
+					session->kernel_session->consumer,
+					new_path);
+			if (ret) {
+				ERR("Failed to rename kernel session trace folder to %s", new_path);
+				/*
+				 * This is not a fatal error for the rotation
+				 * thread, we just need to inform the client
+				 * that a problem occurred with the rotation.
+				 * Returning 0, same for the other errors
+				 * below.
+				 */
+				ret = 0;
+				goto error;
+			}
+		}
+		if (session->ust_session) {
+			ret = rename_first_chunk(session,
+					session->ust_session->consumer,
+					new_path);
+			if (ret) {
+				ERR("Failed to rename userspace session trace folder to %s", new_path);
+				ret = 0;
+				goto error;
+			}
+		}
+	} else {
+		/*
+		 * After the first rotation, all the trace data is already in
+		 * its own chunk folder, we just need to append the suffix.
+		 */
+		/* Recreate the session->rotation_chunk.current_rotate_path */
+		timeinfo = localtime(&session->last_chunk_start_ts);
+		if (!timeinfo) {
+			ERR("Failed to retrieve local time while renaming completed chunk");
+			ret = -1;
+			goto end;
+		}
+		strf_ret = strftime(start_datetime, sizeof(start_datetime), "%Y%m%d-%H%M%S", timeinfo);
+		if (!strf_ret) {
+			ERR("Failed to format timestamp while renaming completed session chunk");
+			ret = -1;
+			goto end;
+		}
+		ret = snprintf(new_path, sizeof(new_path), "%s/%s-%s-%" PRIu64,
+				session_get_base_path(session),
+				start_datetime,
+				datetime, session->rotate_count);
+		if (ret < 0 || ret >= sizeof(new_path)) {
+			ERR("Failed to format new chunk path while renaming chunk of session \"%s\"",
+					session->name);
+			ret = -1;
+			goto error;
+		}
+		ret = session_rename_chunk(session,
+				session->rotation_chunk.current_rotate_path,
+				new_path);
+		if (ret) {
+			ERR("Failed to rename session trace folder from %s to %s",
+					session->rotation_chunk.current_rotate_path,
+					new_path);
+			ret = 0;
+			goto error;
+		}
+	}
+
+	/*
+	 * Store the path where the readable chunk is. This path is valid
+	 * and can be queried by the client with rotate_pending until the next
+	 * rotation is started.
+	 */
+	ret = lttng_strncpy(session->rotation_chunk.current_rotate_path,
+			new_path,
+			sizeof(session->rotation_chunk.current_rotate_path));
+	if (ret) {
+		ERR("Failed the current chunk's path of session \"%s\"",
+				session->name);
+		ret = -1;
+		goto error;
+	}
+
+	goto end;
+
+error:
+	session->rotation_status = LTTNG_ROTATION_STATUS_ERROR;
+end:
+	return ret;
+}