X-Git-Url: http://git.efficios.com/?a=blobdiff_plain;f=src%2Fbin%2Flttng-sessiond%2Fkernel.c;h=75c680ec91f47364c53ba11bb3ab20ae0a515cdc;hb=857d49f38c4fa51ca671c4884235118c5458e5c1;hp=bf9f8b623288eb2e7eb58652bb5f26493ecf399e;hpb=d0ae4ea864f84fa2456563abb20fe42e5cc29625;p=lttng-tools.git diff --git a/src/bin/lttng-sessiond/kernel.c b/src/bin/lttng-sessiond/kernel.c index bf9f8b623..75c680ec9 100644 --- a/src/bin/lttng-sessiond/kernel.c +++ b/src/bin/lttng-sessiond/kernel.c @@ -15,9 +15,7 @@ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. */ -#define _GNU_SOURCE #define _LGPL_SOURCE -#include #include #include #include @@ -38,6 +36,8 @@ /* * Add context on a kernel channel. + * + * Assumes the ownership of ctx. */ int kernel_add_channel_context(struct ltt_kernel_channel *chan, struct ltt_kernel_context *ctx) @@ -50,20 +50,31 @@ int kernel_add_channel_context(struct ltt_kernel_channel *chan, DBG("Adding context to channel %s", chan->channel->name); ret = kernctl_add_context(chan->fd, &ctx->ctx); if (ret < 0) { - if (errno != EEXIST) { - PERROR("add context ioctl"); - } else { + switch (-ret) { + case ENOSYS: + /* Exists but not available for this kernel */ + ret = LTTNG_ERR_KERN_CONTEXT_UNAVAILABLE; + goto error; + case EEXIST: /* If EEXIST, we just ignore the error */ ret = 0; + goto end; + default: + PERROR("add context ioctl"); + ret = LTTNG_ERR_KERN_CONTEXT_FAIL; + goto error; } - goto error; } + ret = 0; +end: cds_list_add_tail(&ctx->list, &chan->ctx_list); - - return 0; - + ctx->in_list = true; + ctx = NULL; error: + if (ctx) { + trace_kernel_destroy_context(ctx); + } return ret; } @@ -177,7 +188,9 @@ error: * We own filter_expression and filter. */ int kernel_create_event(struct lttng_event *ev, - struct ltt_kernel_channel *channel) + struct ltt_kernel_channel *channel, + char *filter_expression, + struct lttng_filter_bytecode *filter) { int ret; struct ltt_kernel_event *event; @@ -185,7 +198,9 @@ int kernel_create_event(struct lttng_event *ev, assert(ev); assert(channel); - event = trace_kernel_create_event(ev); + /* We pass ownership of filter_expression and filter */ + event = trace_kernel_create_event(ev, filter_expression, + filter); if (event == NULL) { ret = -1; goto error; @@ -193,7 +208,7 @@ int kernel_create_event(struct lttng_event *ev, ret = kernctl_create_event(channel->fd, event->event); if (ret < 0) { - switch (errno) { + switch (-ret) { case EEXIST: break; case ENOSYS: @@ -205,7 +220,6 @@ int kernel_create_event(struct lttng_event *ev, default: PERROR("create event ioctl"); } - ret = -errno; goto free_event; } @@ -217,6 +231,26 @@ int kernel_create_event(struct lttng_event *ev, PERROR("fcntl session fd"); } + if (filter) { + ret = kernctl_filter(event->fd, filter); + if (ret) { + goto filter_error; + } + } + + ret = kernctl_enable(event->fd); + if (ret < 0) { + switch (-ret) { + case EEXIST: + ret = LTTNG_ERR_KERN_EVENT_EXIST; + break; + default: + PERROR("enable kernel event"); + break; + } + goto enable_error; + } + /* Add event to event list */ cds_list_add(&event->list, &channel->events_list.head); channel->event_count++; @@ -225,6 +259,16 @@ int kernel_create_event(struct lttng_event *ev, return 0; +enable_error: +filter_error: + { + int closeret; + + closeret = close(event->fd); + if (closeret) { + PERROR("close event fd"); + } + } free_event: free(event); error: @@ -243,7 +287,6 @@ int kernel_disable_channel(struct ltt_kernel_channel *chan) ret = kernctl_disable(chan->fd); if (ret < 0) { PERROR("disable chan ioctl"); - ret = errno; goto error; } @@ -266,7 +309,7 @@ int kernel_enable_channel(struct ltt_kernel_channel *chan) assert(chan); ret = kernctl_enable(chan->fd); - if (ret < 0 && errno != EEXIST) { + if (ret < 0 && ret != -EEXIST) { PERROR("Enable kernel chan"); goto error; } @@ -291,7 +334,7 @@ int kernel_enable_event(struct ltt_kernel_event *event) ret = kernctl_enable(event->fd); if (ret < 0) { - switch (errno) { + switch (-ret) { case EEXIST: ret = LTTNG_ERR_KERN_EVENT_EXIST; break; @@ -322,7 +365,7 @@ int kernel_disable_event(struct ltt_kernel_event *event) ret = kernctl_disable(event->fd); if (ret < 0) { - switch (errno) { + switch (-ret) { case EEXIST: ret = LTTNG_ERR_KERN_EVENT_EXIST; break; @@ -345,16 +388,46 @@ error: int kernel_track_pid(struct ltt_kernel_session *session, int pid) { + int ret; + DBG("Kernel track PID %d for session id %" PRIu64 ".", pid, session->id); - return kernctl_track_pid(session->fd, pid); + ret = kernctl_track_pid(session->fd, pid); + if (!ret) { + return LTTNG_OK; + } + switch (-ret) { + case EINVAL: + 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; + DBG("Kernel untrack PID %d for session id %" PRIu64 ".", pid, session->id); - return kernctl_untrack_pid(session->fd, pid); + ret = kernctl_untrack_pid(session->fd, pid); + if (!ret) { + return LTTNG_OK; + } + switch (-ret) { + case EINVAL: + return LTTNG_ERR_INVALID; + case ENOMEM: + return LTTNG_ERR_NOMEM; + case ENOENT: + return LTTNG_ERR_PID_NOT_TRACKED; + default: + return LTTNG_ERR_UNK; + } } ssize_t kernel_list_tracker_pids(struct ltt_kernel_session *session, @@ -509,25 +582,6 @@ void kernel_wait_quiescent(int fd) } } -/* - * Kernel calibrate - */ -int kernel_calibrate(int fd, struct lttng_kernel_calibrate *calibrate) -{ - int ret; - - assert(calibrate); - - ret = kernctl_calibrate(fd, calibrate); - if (ret < 0) { - PERROR("calibrate ioctl"); - return -1; - } - - return 0; -} - - /* * Force flush buffer of metadata. */ @@ -596,17 +650,22 @@ error: * Open stream of channel, register it to the kernel tracer and add it * to the stream list of the channel. * + * Note: given that the streams may appear in random order wrt CPU + * number (e.g. cpu hotplug), the index value of the stream number in + * the stream name is not necessarily linked to the CPU number. + * * Return the number of created stream. Else, a negative value. */ int kernel_open_channel_stream(struct ltt_kernel_channel *channel) { - int ret, count = 0; + int ret; struct ltt_kernel_stream *lks; assert(channel); while ((ret = kernctl_create_stream(channel->fd)) >= 0) { - lks = trace_kernel_create_stream(channel->channel->name, count); + lks = trace_kernel_create_stream(channel->channel->name, + channel->stream_count); if (lks == NULL) { ret = close(ret); if (ret) { @@ -625,13 +684,10 @@ int kernel_open_channel_stream(struct ltt_kernel_channel *channel) lks->tracefile_size = channel->channel->attr.tracefile_size; lks->tracefile_count = channel->channel->attr.tracefile_count; - /* Add stream to channe stream list */ + /* Add stream to channel stream list */ cds_list_add(&lks->list, &channel->stream_list.head); channel->stream_count++; - /* Increment counter which represent CPU number. */ - count++; - DBG("Kernel stream %s created (fd: %d, state: %d)", lks->name, lks->fd, lks->state); } @@ -766,7 +822,7 @@ int kernel_validate_version(int tracer_fd) ret = kernctl_tracer_version(tracer_fd, &version); if (ret < 0) { - ERR("Failed at getting the lttng-modules version"); + ERR("Failed to retrieve the lttng-modules version"); goto error; } @@ -778,11 +834,11 @@ int kernel_validate_version(int tracer_fd) } ret = kernctl_tracer_abi_version(tracer_fd, &abi_version); if (ret < 0) { - ERR("Failed at getting lttng-modules ABI version"); + ERR("Failed to retrieve lttng-modules ABI version"); goto error; } if (abi_version.major != LTTNG_MODULES_ABI_MAJOR_VERSION) { - ERR("Kernel tracer ABI version (%d.%d) is not compatible with expected ABI major version (%d.*)", + ERR("Kernel tracer ABI version (%d.%d) does not match the expected ABI major version (%d.*)", abi_version.major, abi_version.minor, LTTNG_MODULES_ABI_MAJOR_VERSION); goto error; @@ -796,6 +852,7 @@ error_version: ret = -1; error: + ERR("Kernel tracer version check failed; kernel tracing will not be available"); return ret; } @@ -972,12 +1029,10 @@ int kernel_snapshot_record(struct ltt_kernel_session *ksess, /* 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, 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, @@ -987,11 +1042,9 @@ int kernel_snapshot_record(struct ltt_kernel_session *ksess, } /* Snapshot metadata, */ - pthread_mutex_lock(socket->lock); ret = consumer_snapshot_channel(socket, ksess->metadata->fd, 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; @@ -1037,3 +1090,111 @@ int kernel_syscall_mask(int chan_fd, char **syscall_mask, uint32_t *nr_bits) return kernctl_syscall_mask(chan_fd, syscall_mask, nr_bits); } + +/* + * Check for the support of the RING_BUFFER_SNAPSHOT_SAMPLE_POSITIONS via abi + * version number. + * + * Return 1 on success, 0 when feature is not supported, negative value in case + * of errors. + */ +int kernel_supports_ring_buffer_snapshot_sample_positions(int tracer_fd) +{ + int ret = 0; // Not supported by default + struct lttng_kernel_tracer_abi_version abi; + + ret = kernctl_tracer_abi_version(tracer_fd, &abi); + if (ret < 0) { + ERR("Failed to retrieve lttng-modules ABI version"); + goto error; + } + + /* + * RING_BUFFER_SNAPSHOT_SAMPLE_POSITIONS was introduced in 2.3 + */ + if (abi.major >= 2 && abi.minor >= 3) { + /* Supported */ + ret = 1; + } else { + /* Not supported */ + ret = 0; + } +error: + return ret; +} + +/* + * 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(); + + /* + * 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, + ksess->consumer); + if (ret < 0) { + goto error; + } + } + + if (!ksess->metadata) { + /* + * Nothing to do for the metadata. + * This is a snpashot 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 rotation operation on it behind the scene. + */ + ret = consumer_clear_channel(socket, ksess->metadata->key, + ksess->consumer); + if (ret < 0) { + goto error; + } + } + + goto end; +error: + switch (-ret) { + case LTTCOMM_CONSUMERD_RELAYD_DISALLOW_CLEAR: + status = LTTNG_ERR_CLEAR_RELAY_DISALLOW; + break; + default: + status = LTTNG_ERR_CLEAR_FAIL_CONSUMER; + break; + } +end: + rcu_read_unlock(); + return status; +}