X-Git-Url: https://git.lttng.org/?p=lttng-tools.git;a=blobdiff_plain;f=src%2Fbin%2Flttng-sessiond%2Fkernel.c;h=4ee4bea64ff630abae9617624f86ce21cc87950d;hp=93afc9d6fb25e795aab694bc77b9ace813c5aacb;hb=640b9481e1805d314256361ed49d55dcc35d6172;hpb=5da88b0f58d7f838068037ea449ddfb25d3e85ad

diff --git a/src/bin/lttng-sessiond/kernel.c b/src/bin/lttng-sessiond/kernel.c
index 93afc9d6f..4ee4bea64 100644
--- a/src/bin/lttng-sessiond/kernel.c
+++ b/src/bin/lttng-sessiond/kernel.c
@@ -1,18 +1,8 @@
 /*
- * Copyright (C) 2011 - David Goulet <david.goulet@polymtl.ca>
+ * Copyright (C) 2011 David Goulet <david.goulet@polymtl.ca>
  *
- * 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.
  */
 
 #define _LGPL_SOURCE
@@ -679,120 +669,281 @@ error:
 	return ret;
 }
 
+static struct lttng_tracker_list *get_id_tracker_list(
+		struct ltt_kernel_session *session,
+		enum lttng_tracker_type tracker_type)
+{
+	switch (tracker_type) {
+	case LTTNG_TRACKER_PID:
+		return session->tracker_list_pid;
+	case LTTNG_TRACKER_VPID:
+		return session->tracker_list_vpid;
+	case LTTNG_TRACKER_UID:
+		return session->tracker_list_uid;
+	case LTTNG_TRACKER_VUID:
+		return session->tracker_list_vuid;
+	case LTTNG_TRACKER_GID:
+		return session->tracker_list_gid;
+	case LTTNG_TRACKER_VGID:
+		return session->tracker_list_vgid;
+	default:
+		return NULL;
+	}
+}
 
-int kernel_track_pid(struct ltt_kernel_session *session, int pid)
+int kernel_track_id(enum lttng_tracker_type tracker_type,
+		struct ltt_kernel_session *session,
+		const struct lttng_tracker_id *id)
 {
-	int ret;
+	int ret, value;
+	struct lttng_tracker_list *tracker_list;
+	struct lttng_tracker_ids *saved_ids;
 
-	DBG("Kernel track PID %d for session id %" PRIu64 ".",
-			pid, session->id);
-	ret = kernctl_track_pid(session->fd, pid);
-	if (!ret) {
-		return LTTNG_OK;
+	ret = lttng_tracker_id_lookup_string(tracker_type, id, &value);
+	if (ret != LTTNG_OK) {
+		return ret;
 	}
-	switch (-ret) {
-	case EINVAL:
+
+	tracker_list = get_id_tracker_list(session, tracker_type);
+	if (!tracker_list) {
 		return LTTNG_ERR_INVALID;
-	case ENOMEM:
-		return LTTNG_ERR_NOMEM;
-	case EEXIST:
-		return LTTNG_ERR_PID_TRACKED;
-	default:
-		return LTTNG_ERR_UNK;
 	}
-}
 
-int kernel_untrack_pid(struct ltt_kernel_session *session, int pid)
-{
-	int ret;
+	/* Save list for restore on error. */
+	ret = lttng_tracker_id_get_list(tracker_list, &saved_ids);
+	if (ret != LTTNG_OK) {
+		return LTTNG_ERR_INVALID;
+	}
+
+	/* Add to list. */
+	ret = lttng_tracker_list_add(tracker_list, id);
+	if (ret != LTTNG_OK) {
+		goto end;
+	}
 
-	DBG("Kernel untrack PID %d for session id %" PRIu64 ".",
-			pid, session->id);
-	ret = kernctl_untrack_pid(session->fd, pid);
-	if (!ret) {
-		return LTTNG_OK;
+	switch (tracker_type) {
+	case LTTNG_TRACKER_PID:
+		DBG("Kernel track PID %d for session id %" PRIu64 ".", value,
+				session->id);
+		ret = kernctl_track_pid(session->fd, value);
+		if (!ret) {
+			ret = LTTNG_OK;
+			goto end;
+		}
+		break;
+	case LTTNG_TRACKER_VPID:
+		DBG("Kernel track VPID %d for session id %" PRIu64 ".", value,
+				session->id);
+		ret = kernctl_track_id(session->fd, LTTNG_TRACKER_VPID, value);
+		if (!ret) {
+			ret = LTTNG_OK;
+			goto end;
+		}
+		break;
+	case LTTNG_TRACKER_UID:
+		DBG("Kernel track UID %d for session id %" PRIu64 ".", value,
+				session->id);
+		ret = kernctl_track_id(session->fd, LTTNG_TRACKER_UID, value);
+		if (!ret) {
+			ret = LTTNG_OK;
+			goto end;
+		}
+		break;
+	case LTTNG_TRACKER_GID:
+		DBG("Kernel track GID %d for session id %" PRIu64 ".", value,
+				session->id);
+		ret = kernctl_track_id(session->fd, LTTNG_TRACKER_GID, value);
+		if (!ret) {
+			ret = LTTNG_OK;
+			goto end;
+		}
+		break;
+	case LTTNG_TRACKER_VUID:
+		DBG("Kernel track VUID %d for session id %" PRIu64 ".", value,
+				session->id);
+		ret = kernctl_track_id(session->fd, LTTNG_TRACKER_VUID, value);
+		if (!ret) {
+			ret = LTTNG_OK;
+			goto end;
+		}
+		break;
+	case LTTNG_TRACKER_VGID:
+		DBG("Kernel track VGID %d for session id %" PRIu64 ".", value,
+				session->id);
+		ret = kernctl_track_id(session->fd, LTTNG_TRACKER_VGID, value);
+		if (!ret) {
+			ret = LTTNG_OK;
+			goto end;
+		}
+		break;
+	default:
+		ret = -EINVAL;
+		break;
 	}
+
+	/* Error handling. */
 	switch (-ret) {
 	case EINVAL:
-		return LTTNG_ERR_INVALID;
+		ret = LTTNG_ERR_INVALID;
+		break;
 	case ENOMEM:
-		return LTTNG_ERR_NOMEM;
-	case ENOENT:
-		return LTTNG_ERR_PID_NOT_TRACKED;
+		ret = LTTNG_ERR_NOMEM;
+		break;
+	case EEXIST:
+		ret = LTTNG_ERR_ID_TRACKED;
+		break;
 	default:
-		return LTTNG_ERR_UNK;
+		ret = LTTNG_ERR_UNK;
+		break;
+	}
+
+	if (lttng_tracker_id_set_list(tracker_list, saved_ids) != LTTNG_OK) {
+		ERR("Error on tracker add error handling.\n");
 	}
+end:
+	lttng_tracker_ids_destroy(saved_ids);
+	return ret;
 }
 
-ssize_t kernel_list_tracker_pids(struct ltt_kernel_session *session,
-		int **_pids)
+int kernel_untrack_id(enum lttng_tracker_type tracker_type,
+		struct ltt_kernel_session *session,
+		const struct lttng_tracker_id *id)
 {
-	int fd, ret;
-	int pid;
-	ssize_t nbmem, count = 0;
-	FILE *fp;
-	int *pids;
+	int ret, value;
+	struct lttng_tracker_list *tracker_list;
+	struct lttng_tracker_ids *saved_ids;
 
-	fd = kernctl_list_tracker_pids(session->fd);
-	if (fd < 0) {
-		PERROR("kernel tracker pids list");
-		goto error;
+	ret = lttng_tracker_id_lookup_string(tracker_type, id, &value);
+	if (ret != LTTNG_OK) {
+		return ret;
 	}
 
-	fp = fdopen(fd, "r");
-	if (fp == NULL) {
-		PERROR("kernel tracker pids list fdopen");
-		goto error_fp;
+	tracker_list = get_id_tracker_list(session, tracker_type);
+	if (!tracker_list) {
+		return LTTNG_ERR_INVALID;
 	}
-
-	nbmem = KERNEL_TRACKER_PIDS_INIT_LIST_SIZE;
-	pids = zmalloc(sizeof(*pids) * nbmem);
-	if (pids == NULL) {
-		PERROR("alloc list pids");
-		count = -ENOMEM;
+	/* Save list for restore on error. */
+	ret = lttng_tracker_id_get_list(tracker_list, &saved_ids);
+	if (ret != LTTNG_OK) {
+		return LTTNG_ERR_INVALID;
+	}
+	/* Remove from list. */
+	ret = lttng_tracker_list_remove(tracker_list, id);
+	if (ret != LTTNG_OK) {
 		goto end;
 	}
 
-	while (fscanf(fp, "process { pid = %u; };\n", &pid) == 1) {
-		if (count >= nbmem) {
-			int *new_pids;
-			size_t new_nbmem;
-
-			new_nbmem = nbmem << 1;
-			DBG("Reallocating pids list from %zu to %zu entries",
-					nbmem, new_nbmem);
-			new_pids = realloc(pids, new_nbmem * sizeof(*new_pids));
-			if (new_pids == NULL) {
-				PERROR("realloc list events");
-				free(pids);
-				count = -ENOMEM;
-				goto end;
-			}
-			/* Zero the new memory */
-			memset(new_pids + nbmem, 0,
-				(new_nbmem - nbmem) * sizeof(*new_pids));
-			nbmem = new_nbmem;
-			pids = new_pids;
+	switch (tracker_type) {
+	case LTTNG_TRACKER_PID:
+		DBG("Kernel untrack PID %d for session id %" PRIu64 ".", value,
+				session->id);
+		ret = kernctl_untrack_pid(session->fd, value);
+		if (!ret) {
+			ret = LTTNG_OK;
+			goto end;
+		}
+		break;
+	case LTTNG_TRACKER_VPID:
+		DBG("Kernel untrack VPID %d for session id %" PRIu64 ".", value,
+				session->id);
+		ret = kernctl_untrack_id(
+				session->fd, LTTNG_TRACKER_VPID, value);
+		if (!ret) {
+			ret = LTTNG_OK;
+			goto end;
 		}
-		pids[count++] = pid;
+		break;
+	case LTTNG_TRACKER_UID:
+		DBG("Kernel untrack UID %d for session id %" PRIu64 ".", value,
+				session->id);
+		ret = kernctl_untrack_id(session->fd, LTTNG_TRACKER_UID, value);
+		if (!ret) {
+			ret = LTTNG_OK;
+			goto end;
+		}
+		break;
+	case LTTNG_TRACKER_GID:
+		DBG("Kernel untrack GID %d for session id %" PRIu64 ".", value,
+				session->id);
+		ret = kernctl_untrack_id(session->fd, LTTNG_TRACKER_GID, value);
+		if (!ret) {
+			ret = LTTNG_OK;
+			goto end;
+		}
+		break;
+	case LTTNG_TRACKER_VUID:
+		DBG("Kernel untrack VUID %d for session id %" PRIu64 ".", value,
+				session->id);
+		ret = kernctl_untrack_id(
+				session->fd, LTTNG_TRACKER_VUID, value);
+		if (!ret) {
+			ret = LTTNG_OK;
+			goto end;
+		}
+		break;
+	case LTTNG_TRACKER_VGID:
+		DBG("Kernel untrack VGID %d for session id %" PRIu64 ".", value,
+				session->id);
+		ret = kernctl_untrack_id(
+				session->fd, LTTNG_TRACKER_VGID, value);
+		if (!ret) {
+			ret = LTTNG_OK;
+			goto end;
+		}
+		break;
+	default:
+		ret = -EINVAL;
+		break;
+	}
+
+	/* Error handling. */
+	switch (-ret) {
+	case EINVAL:
+		ret = LTTNG_ERR_INVALID;
+		break;
+	case ENOMEM:
+		ret = LTTNG_ERR_NOMEM;
+		break;
+	case EEXIST:
+		ret = LTTNG_ERR_ID_TRACKED;
+		break;
+	default:
+		ret = LTTNG_ERR_UNK;
+		break;
 	}
 
-	*_pids = pids;
-	DBG("Kernel list tracker pids done (%zd pids)", count);
+	if (lttng_tracker_id_set_list(tracker_list, saved_ids) != LTTNG_OK) {
+		ERR("Error on tracker remove error handling.\n");
+	}
 end:
-	ret = fclose(fp);	/* closes both fp and fd */
-	if (ret) {
-		PERROR("fclose");
+	lttng_tracker_ids_destroy(saved_ids);
+	return ret;
+}
+
+/*
+ * Called with session lock held.
+ */
+int kernel_list_tracker_ids(enum lttng_tracker_type tracker_type,
+		struct ltt_kernel_session *session,
+		struct lttng_tracker_ids **_ids)
+{
+	int ret = 0;
+	struct lttng_tracker_list *tracker_list;
+
+	tracker_list = get_id_tracker_list(session, tracker_type);
+	if (!tracker_list) {
+		ret = -LTTNG_ERR_INVALID;
+		goto end;
 	}
-	return count;
 
-error_fp:
-	ret = close(fd);
-	if (ret) {
-		PERROR("close");
+	ret = lttng_tracker_id_get_list(tracker_list, _ids);
+	if (ret != LTTNG_OK) {
+		ret = -LTTNG_ERR_INVALID;
+		goto end;
 	}
-error:
-	return -1;
+
+end:
+	return ret;
 }
 
 /*
@@ -1445,9 +1596,10 @@ int kernel_supports_ring_buffer_packet_sequence_number(void)
 	}
 
 	/*
-	 * Packet sequence number was introduced in 2.8
+	 * Packet sequence number was introduced in LTTng 2.8,
+	 * lttng-modules ABI 2.1.
 	 */
-	if (abi.major >= 2 && abi.minor >= 8) {
+	if (abi.major >= 2 && abi.minor >= 1) {
 		/* Supported */
 		ret = 1;
 	} else {
@@ -1647,3 +1799,83 @@ bool kernel_tracer_is_initialized(void)
 {
 	return kernel_tracer_fd >= 0;
 }
+
+/*
+ *  Clear a kernel session.
+ *
+ * Return LTTNG_OK on success or else an LTTng error code.
+ */
+enum lttng_error_code kernel_clear_session(struct ltt_session *session)
+{
+	int ret;
+	enum lttng_error_code status = LTTNG_OK;
+	struct consumer_socket *socket;
+	struct lttng_ht_iter iter;
+	struct ltt_kernel_session *ksess = session->kernel_session;
+
+	assert(ksess);
+	assert(ksess->consumer);
+
+	DBG("Clear kernel session %s (session %" PRIu64 ")",
+			session->name, session->id);
+
+	rcu_read_lock();
+
+	if (ksess->active) {
+		ERR("Expecting inactive session %s (%" PRIu64 ")", session->name, session->id);
+		status = LTTNG_ERR_FATAL;
+		goto end;
+	}
+
+	/*
+	 * 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;
+
+		/* For each channel, ask the consumer to clear it. */
+		cds_list_for_each_entry(chan, &ksess->channel_list.head, list) {
+			DBG("Clear kernel channel %" PRIu64 ", session %s",
+					chan->key, session->name);
+			ret = consumer_clear_channel(socket, chan->key);
+			if (ret < 0) {
+				goto error;
+			}
+		}
+
+		if (!ksess->metadata) {
+			/*
+			 * Nothing to do for the metadata.
+			 * This is a snapshot session.
+			 * The metadata is genererated on the fly.
+			 */
+			continue;
+		}
+
+		/*
+		 * Clear the metadata channel.
+		 * Metadata channel is not cleared per se but we still need to
+		 * perform a rotation operation on it behind the scene.
+		 */
+		ret = consumer_clear_channel(socket, ksess->metadata->key);
+		if (ret < 0) {
+			goto error;
+		}
+	}
+
+	goto end;
+error:
+	switch (-ret) {
+	case LTTCOMM_CONSUMERD_RELAYD_CLEAR_DISALLOWED:
+	      status = LTTNG_ERR_CLEAR_RELAY_DISALLOWED;
+	      break;
+	default:
+	      status = LTTNG_ERR_CLEAR_FAIL_CONSUMER;
+	      break;
+	}
+end:
+	rcu_read_unlock();
+	return status;
+}