X-Git-Url: http://git.efficios.com/?p=lttng-tools.git;a=blobdiff_plain;f=src%2Fbin%2Flttng-sessiond%2Fust-app.c;h=d3c28883c74bea2416d9afb8a5f0db7c87c03f91;hp=4066b065c0a0b45185e0f18b18820bde9f344c73;hb=44cdb3a261262ebabea3fb0cae9360ac05e66f2c;hpb=2106efa08d11229241a114d1d71635a02006690e diff --git a/src/bin/lttng-sessiond/ust-app.c b/src/bin/lttng-sessiond/ust-app.c index 4066b065c..d3c28883c 100644 --- a/src/bin/lttng-sessiond/ust-app.c +++ b/src/bin/lttng-sessiond/ust-app.c @@ -1,5 +1,6 @@ /* * Copyright (C) 2011 - David Goulet + * Copyright (C) 2016 - Jérémie Galarneau * * 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, @@ -15,7 +16,6 @@ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. */ -#define _GNU_SOURCE #define _LGPL_SOURCE #include #include @@ -27,7 +27,6 @@ #include #include #include -#include #include #include @@ -38,8 +37,17 @@ #include "health-sessiond.h" #include "ust-app.h" #include "ust-consumer.h" -#include "ust-ctl.h" +#include "lttng-ust-ctl.h" +#include "lttng-ust-error.h" #include "utils.h" +#include "session.h" +#include "lttng-sessiond.h" +#include "notification-thread-commands.h" +#include "rotate.h" + +struct lttng_ht *ust_app_ht; +struct lttng_ht *ust_app_ht_by_sock; +struct lttng_ht *ust_app_ht_by_notify_sock; static int ust_app_flush_app_session(struct ust_app *app, struct ust_app_session *ua_sess); @@ -89,6 +97,7 @@ static void copy_channel_attr_to_ustctl( attr->switch_timer_interval = uattr->switch_timer_interval; attr->read_timer_interval = uattr->read_timer_interval; attr->output = uattr->output; + attr->blocking_timeout = uattr->u.s.blocking_timeout; } /* @@ -245,7 +254,8 @@ static struct ust_registry_session *get_session_registry( case LTTNG_BUFFER_PER_UID: { struct buffer_reg_uid *reg_uid = buffer_reg_uid_find( - ua_sess->tracing_id, ua_sess->bits_per_long, ua_sess->uid); + ua_sess->tracing_id, ua_sess->bits_per_long, + ua_sess->real_credentials.uid); if (!reg_uid) { goto error; } @@ -371,9 +381,77 @@ void delete_ust_app_channel_rcu(struct rcu_head *head) free(ua_chan); } +/* + * Extract the lost packet or discarded events counter when the channel is + * being deleted and store the value in the parent channel so we can + * access it from lttng list and at stop/destroy. + * + * The session list lock must be held by the caller. + */ +static +void save_per_pid_lost_discarded_counters(struct ust_app_channel *ua_chan) +{ + uint64_t discarded = 0, lost = 0; + struct ltt_session *session; + struct ltt_ust_channel *uchan; + + if (ua_chan->attr.type != LTTNG_UST_CHAN_PER_CPU) { + return; + } + + rcu_read_lock(); + session = session_find_by_id(ua_chan->session->tracing_id); + if (!session || !session->ust_session) { + /* + * Not finding the session is not an error because there are + * multiple ways the channels can be torn down. + * + * 1) The session daemon can initiate the destruction of the + * ust app session after receiving a destroy command or + * during its shutdown/teardown. + * 2) The application, since we are in per-pid tracing, is + * unregistering and tearing down its ust app session. + * + * Both paths are protected by the session list lock which + * ensures that the accounting of lost packets and discarded + * events is done exactly once. The session is then unpublished + * from the session list, resulting in this condition. + */ + goto end; + } + + if (ua_chan->attr.overwrite) { + consumer_get_lost_packets(ua_chan->session->tracing_id, + ua_chan->key, session->ust_session->consumer, + &lost); + } else { + consumer_get_discarded_events(ua_chan->session->tracing_id, + ua_chan->key, session->ust_session->consumer, + &discarded); + } + uchan = trace_ust_find_channel_by_name( + session->ust_session->domain_global.channels, + ua_chan->name); + if (!uchan) { + ERR("Missing UST channel to store discarded counters"); + goto end; + } + + uchan->per_pid_closed_app_discarded += discarded; + uchan->per_pid_closed_app_lost += lost; + +end: + rcu_read_unlock(); + if (session) { + session_put(session); + } +} + /* * Delete ust app channel safely. RCU read lock must be held before calling * this function. + * + * The session list lock must be held by the caller. */ static void delete_ust_app_channel(int sock, struct ust_app_channel *ua_chan, @@ -416,7 +494,16 @@ void delete_ust_app_channel(int sock, struct ust_app_channel *ua_chan, /* Wipe and free registry from session registry. */ registry = get_session_registry(ua_chan->session); if (registry) { - ust_registry_channel_del_free(registry, ua_chan->key); + ust_registry_channel_del_free(registry, ua_chan->key, + sock >= 0); + } + /* + * A negative socket can be used by the caller when + * cleaning-up a ua_chan in an error path. Skip the + * accounting in this case. + */ + if (sock >= 0) { + save_per_pid_lost_discarded_counters(ua_chan); } } @@ -484,7 +571,7 @@ ssize_t ust_app_push_metadata(struct ust_registry_session *registry, char *metadata_str = NULL; size_t len, offset, new_metadata_len_sent; ssize_t ret_val; - uint64_t metadata_key; + uint64_t metadata_key, metadata_version; assert(registry); assert(socket); @@ -499,21 +586,10 @@ ssize_t ust_app_push_metadata(struct ust_registry_session *registry, return 0; } - /* - * On a push metadata error either the consumer is dead or the - * metadata channel has been destroyed because its endpoint - * might have died (e.g: relayd), or because the application has - * exited. If so, the metadata closed flag is set to 1 so we - * deny pushing metadata again which is not valid anymore on the - * consumer side. - */ - if (registry->metadata_closed) { - return -EPIPE; - } - offset = registry->metadata_len_sent; len = registry->metadata_len - registry->metadata_len_sent; new_metadata_len_sent = registry->metadata_len; + metadata_version = registry->metadata_version; if (len == 0) { DBG3("No metadata to push for metadata key %" PRIu64, registry->metadata_key); @@ -550,7 +626,7 @@ push_data: * different bidirectionnal communication sockets. */ ret = consumer_push_metadata(socket, metadata_key, - metadata_str, len, offset); + metadata_str, len, offset, metadata_version); pthread_mutex_lock(®istry->lock); if (ret < 0) { /* @@ -669,6 +745,10 @@ error: * nullified. The session lock MUST be held unless the application is * in the destroy path. * + * Do not hold the registry lock while communicating with the consumerd, because + * doing so causes inter-process deadlocks between consumerd and sessiond with + * the metadata request notification. + * * Return 0 on success else a negative value. */ static int close_metadata(struct ust_registry_session *registry, @@ -676,6 +756,8 @@ static int close_metadata(struct ust_registry_session *registry, { int ret; struct consumer_socket *socket; + uint64_t metadata_key; + bool registry_was_already_closed; assert(registry); assert(consumer); @@ -683,8 +765,19 @@ static int close_metadata(struct ust_registry_session *registry, rcu_read_lock(); pthread_mutex_lock(®istry->lock); + metadata_key = registry->metadata_key; + registry_was_already_closed = registry->metadata_closed; + if (metadata_key != 0) { + /* + * Metadata closed. Even on error this means that the consumer + * is not responding or not found so either way a second close + * should NOT be emit for this registry. + */ + registry->metadata_closed = 1; + } + pthread_mutex_unlock(®istry->lock); - if (!registry->metadata_key || registry->metadata_closed) { + if (metadata_key == 0 || registry_was_already_closed) { ret = 0; goto end; } @@ -694,23 +787,15 @@ static int close_metadata(struct ust_registry_session *registry, consumer); if (!socket) { ret = -1; - goto error; + goto end; } - ret = consumer_close_metadata(socket, registry->metadata_key); + ret = consumer_close_metadata(socket, metadata_key); if (ret < 0) { - goto error; + goto end; } -error: - /* - * Metadata closed. Even on error this means that the consumer is not - * responding or not found so either way a second close should NOT be emit - * for this registry. - */ - registry->metadata_closed = 1; end: - pthread_mutex_unlock(®istry->lock); rcu_read_unlock(); return ret; } @@ -734,6 +819,8 @@ void delete_ust_app_session_rcu(struct rcu_head *head) /* * Delete ust app session safely. RCU read lock must be held before calling * this function. + * + * The session list lock must be held by the caller. */ static void delete_ust_app_session(int sock, struct ust_app_session *ua_sess, @@ -752,6 +839,7 @@ void delete_ust_app_session(int sock, struct ust_app_session *ua_sess, ua_sess->deleted = true; registry = get_session_registry(ua_sess); + /* Registry can be null on error path during initialization. */ if (registry) { /* Push metadata for application before freeing the application. */ (void) push_metadata(registry, ua_sess->consumer); @@ -779,6 +867,10 @@ void delete_ust_app_session(int sock, struct ust_app_session *ua_sess, if (ua_sess->buffer_type == LTTNG_BUFFER_PER_PID) { struct buffer_reg_pid *reg_pid = buffer_reg_pid_find(ua_sess->id); if (reg_pid) { + /* + * Registry can be null on error path during + * initialization. + */ buffer_reg_pid_remove(reg_pid); buffer_reg_pid_destroy(reg_pid); } @@ -792,7 +884,12 @@ void delete_ust_app_session(int sock, struct ust_app_session *ua_sess, ERR("UST app sock %d release session handle failed with ret %d", sock, ret); } + /* Remove session from application UST object descriptor. */ + iter.iter.node = &ua_sess->ust_objd_node.node; + ret = lttng_ht_del(app->ust_sessions_objd, &iter); + assert(!ret); } + pthread_mutex_unlock(&ua_sess->lock); consumer_output_put(ua_sess->consumer); @@ -812,6 +909,11 @@ void delete_ust_app(struct ust_app *app) int ret, sock; struct ust_app_session *ua_sess, *tmp_ua_sess; + /* + * The session list lock must be held during this function to guarantee + * the existence of ua_sess. + */ + session_lock_list(); /* Delete ust app sessions info */ sock = app->sock; app->sock = -1; @@ -826,6 +928,7 @@ void delete_ust_app(struct ust_app *app) } ht_cleanup_push(app->sessions); + ht_cleanup_push(app->ust_sessions_objd); ht_cleanup_push(app->ust_objd); /* @@ -849,6 +952,7 @@ void delete_ust_app(struct ust_app *app) DBG2("UST app pid %d deleted", app->pid); free(app); + session_unlock_list(); } /* @@ -869,6 +973,8 @@ void delete_ust_app_rcu(struct rcu_head *head) /* * Delete the session from the application ht and delete the data structure by * freeing every object inside and releasing them. + * + * The session list lock must be held by the caller. */ static void destroy_app_session(struct ust_app *app, struct ust_app_session *ua_sess) @@ -897,7 +1003,7 @@ end: * Alloc new UST app session. */ static -struct ust_app_session *alloc_ust_app_session(struct ust_app *app) +struct ust_app_session *alloc_ust_app_session(void) { struct ust_app_session *ua_sess; @@ -960,6 +1066,7 @@ struct ust_app_channel *alloc_ust_app_channel(char *name, ua_chan->attr.switch_timer_interval = attr->switch_timer_interval; ua_chan->attr.read_timer_interval = attr->read_timer_interval; ua_chan->attr.output = attr->output; + ua_chan->attr.blocking_timeout = attr->u.s.blocking_timeout; } /* By default, the channel is a per cpu channel. */ ua_chan->attr.type = LTTNG_UST_CHAN_PER_CPU; @@ -1006,7 +1113,7 @@ struct ust_app_event *alloc_ust_app_event(char *name, /* Init most of the default value by allocating and zeroing */ ua_event = zmalloc(sizeof(struct ust_app_event)); if (ua_event == NULL) { - PERROR("malloc"); + PERROR("Failed to allocate ust_app_event structure"); goto error; } @@ -1032,7 +1139,7 @@ error: * Alloc new UST app context. */ static -struct ust_app_ctx *alloc_ust_app_ctx(struct lttng_ust_context *uctx) +struct ust_app_ctx *alloc_ust_app_ctx(struct lttng_ust_context_attr *uctx) { struct ust_app_ctx *ua_ctx; @@ -1045,12 +1152,27 @@ struct ust_app_ctx *alloc_ust_app_ctx(struct lttng_ust_context *uctx) if (uctx) { memcpy(&ua_ctx->ctx, uctx, sizeof(ua_ctx->ctx)); + if (uctx->ctx == LTTNG_UST_CONTEXT_APP_CONTEXT) { + char *provider_name = NULL, *ctx_name = NULL; + + provider_name = strdup(uctx->u.app_ctx.provider_name); + ctx_name = strdup(uctx->u.app_ctx.ctx_name); + if (!provider_name || !ctx_name) { + free(provider_name); + free(ctx_name); + goto error; + } + + ua_ctx->ctx.u.app_ctx.provider_name = provider_name; + ua_ctx->ctx.u.app_ctx.ctx_name = ctx_name; + } } DBG3("UST app context %d allocated", ua_ctx->ctx.ctx); - -error: return ua_ctx; +error: + free(ua_ctx); + return NULL; } /* @@ -1152,7 +1274,7 @@ error: * Return an ust_app_event object or NULL on error. */ static struct ust_app_event *find_ust_app_event(struct lttng_ht *ht, - char *name, struct lttng_filter_bytecode *filter, + const char *name, const struct lttng_filter_bytecode *filter, int loglevel_value, const struct lttng_event_exclusion *exclusion) { @@ -1213,7 +1335,7 @@ int create_ust_channel_context(struct ust_app_channel *ua_chan, * continue normally. */ ret = 0; - DBG3("UST app disable event failed. Application is dead."); + DBG3("UST app add context failed. Application is dead."); } goto error; } @@ -1575,6 +1697,7 @@ int create_ust_event(struct ust_app *app, struct ust_app_session *ua_sess, pthread_mutex_unlock(&app->sock_lock); if (ret < 0) { if (ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) { + abort(); ERR("Error ustctl create event %s for app pid: %d with ret %d", ua_event->attr.name, app->pid, ret); } else { @@ -1687,12 +1810,6 @@ static void shadow_copy_event(struct ust_app_event *ua_event, static void shadow_copy_channel(struct ust_app_channel *ua_chan, struct ltt_ust_channel *uchan) { - struct lttng_ht_iter iter; - struct ltt_ust_event *uevent; - struct ltt_ust_context *uctx; - struct ust_app_event *ua_event; - struct ust_app_ctx *ua_ctx; - DBG2("UST app shadow copy of channel %s started", ua_chan->name); strncpy(ua_chan->name, uchan->name, sizeof(ua_chan->name)); @@ -1707,7 +1824,10 @@ static void shadow_copy_channel(struct ust_app_channel *ua_chan, ua_chan->attr.overwrite = uchan->attr.overwrite; ua_chan->attr.switch_timer_interval = uchan->attr.switch_timer_interval; ua_chan->attr.read_timer_interval = uchan->attr.read_timer_interval; + ua_chan->monitor_timer_interval = uchan->monitor_timer_interval; ua_chan->attr.output = uchan->attr.output; + ua_chan->attr.blocking_timeout = uchan->attr.u.s.blocking_timeout; + /* * Note that the attribute channel type is not set since the channel on the * tracing registry side does not have this information. @@ -1716,33 +1836,6 @@ static void shadow_copy_channel(struct ust_app_channel *ua_chan, ua_chan->enabled = uchan->enabled; ua_chan->tracing_channel_id = uchan->id; - cds_list_for_each_entry(uctx, &uchan->ctx_list, list) { - ua_ctx = alloc_ust_app_ctx(&uctx->ctx); - if (ua_ctx == NULL) { - continue; - } - lttng_ht_node_init_ulong(&ua_ctx->node, - (unsigned long) ua_ctx->ctx.ctx); - lttng_ht_add_ulong(ua_chan->ctx, &ua_ctx->node); - cds_list_add_tail(&ua_ctx->list, &ua_chan->ctx_list); - } - - /* Copy all events from ltt ust channel to ust app channel */ - cds_lfht_for_each_entry(uchan->events->ht, &iter.iter, uevent, node.node) { - ua_event = find_ust_app_event(ua_chan->events, uevent->attr.name, - uevent->filter, uevent->attr.loglevel, uevent->exclusion); - if (ua_event == NULL) { - DBG2("UST event %s not found on shadow copy channel", - uevent->attr.name); - ua_event = alloc_ust_app_event(uevent->attr.name, &uevent->attr); - if (ua_event == NULL) { - continue; - } - shadow_copy_event(ua_event, uevent); - add_unique_ust_app_event(ua_chan, ua_event); - } - } - DBG3("UST app shadow copy of channel %s done", ua_chan->name); } @@ -1752,29 +1845,22 @@ static void shadow_copy_channel(struct ust_app_channel *ua_chan, static void shadow_copy_session(struct ust_app_session *ua_sess, struct ltt_ust_session *usess, struct ust_app *app) { - struct lttng_ht_node_str *ua_chan_node; - struct lttng_ht_iter iter; - struct ltt_ust_channel *uchan; - struct ust_app_channel *ua_chan; - time_t rawtime; struct tm *timeinfo; char datetime[16]; int ret; char tmp_shm_path[PATH_MAX]; - /* Get date and time for unique app path */ - time(&rawtime); - timeinfo = localtime(&rawtime); + timeinfo = localtime(&app->registration_time); strftime(datetime, sizeof(datetime), "%Y%m%d-%H%M%S", timeinfo); DBG2("Shadow copy of session handle %d", ua_sess->handle); ua_sess->tracing_id = usess->id; ua_sess->id = get_next_session_id(); - ua_sess->uid = app->uid; - ua_sess->gid = app->gid; - ua_sess->euid = usess->uid; - ua_sess->egid = usess->gid; + ua_sess->real_credentials.uid = app->uid; + ua_sess->real_credentials.gid = app->gid; + ua_sess->effective_credentials.uid = usess->uid; + ua_sess->effective_credentials.gid = usess->gid; ua_sess->buffer_type = usess->buffer_type; ua_sess->bits_per_long = app->bits_per_long; @@ -1795,7 +1881,9 @@ static void shadow_copy_session(struct ust_app_session *ua_sess, break; case LTTNG_BUFFER_PER_UID: ret = snprintf(ua_sess->path, sizeof(ua_sess->path), - DEFAULT_UST_TRACE_UID_PATH, ua_sess->uid, app->bits_per_long); + DEFAULT_UST_TRACE_UID_PATH, + ua_sess->real_credentials.uid, + app->bits_per_long); break; default: assert(0); @@ -1817,12 +1905,12 @@ static void shadow_copy_session(struct ust_app_session *ua_sess, switch (ua_sess->buffer_type) { case LTTNG_BUFFER_PER_PID: ret = snprintf(tmp_shm_path, sizeof(tmp_shm_path), - DEFAULT_UST_TRACE_PID_PATH "/%s-%d-%s", + "/" DEFAULT_UST_TRACE_PID_PATH "/%s-%d-%s", app->name, app->pid, datetime); break; case LTTNG_BUFFER_PER_UID: ret = snprintf(tmp_shm_path, sizeof(tmp_shm_path), - DEFAULT_UST_TRACE_UID_PATH, + "/" DEFAULT_UST_TRACE_UID_PATH, app->uid, app->bits_per_long); break; default: @@ -1838,36 +1926,6 @@ static void shadow_copy_session(struct ust_app_session *ua_sess, sizeof(ua_sess->shm_path) - strlen(ua_sess->shm_path) - 1); ua_sess->shm_path[sizeof(ua_sess->shm_path) - 1] = '\0'; } - - /* Iterate over all channels in global domain. */ - cds_lfht_for_each_entry(usess->domain_global.channels->ht, &iter.iter, - uchan, node.node) { - struct lttng_ht_iter uiter; - - lttng_ht_lookup(ua_sess->channels, (void *)uchan->name, &uiter); - ua_chan_node = lttng_ht_iter_get_node_str(&uiter); - if (ua_chan_node != NULL) { - /* Session exist. Contiuing. */ - continue; - } - - DBG2("Channel %s not found on shadow session copy, creating it", - uchan->name); - ua_chan = alloc_ust_app_channel(uchan->name, ua_sess, &uchan->attr); - if (ua_chan == NULL) { - /* malloc failed FIXME: Might want to do handle ENOMEM .. */ - continue; - } - shadow_copy_channel(ua_chan, uchan); - /* - * The concept of metadata channel does not exist on the tracing - * registry side of the session daemon so this can only be a per CPU - * channel and not metadata. - */ - ua_chan->attr.type = LTTNG_UST_CHAN_PER_CPU; - - lttng_ht_add_unique_str(ua_sess->channels, &ua_chan->node); - } return; error: @@ -1878,7 +1936,7 @@ error: * Lookup sesison wrapper. */ static -void __lookup_session_by_app(struct ltt_ust_session *usess, +void __lookup_session_by_app(const struct ltt_ust_session *usess, struct ust_app *app, struct lttng_ht_iter *iter) { /* Get right UST app session from app */ @@ -1890,7 +1948,7 @@ void __lookup_session_by_app(struct ltt_ust_session *usess, * id. */ static struct ust_app_session *lookup_session_by_app( - struct ltt_ust_session *usess, struct ust_app *app) + const struct ltt_ust_session *usess, struct ust_app *app) { struct lttng_ht_iter iter; struct lttng_ht_node_u64 *node; @@ -1945,10 +2003,11 @@ static int setup_buffer_reg_pid(struct ust_app_session *ua_sess, app->bits_per_long, app->uint8_t_alignment, app->uint16_t_alignment, app->uint32_t_alignment, app->uint64_t_alignment, app->long_alignment, - app->byte_order, app->version.major, - app->version.minor, reg_pid->root_shm_path, - reg_pid->shm_path, - ua_sess->euid, ua_sess->egid); + app->byte_order, app->version.major, app->version.minor, + reg_pid->root_shm_path, reg_pid->shm_path, + ua_sess->effective_credentials.uid, + ua_sess->effective_credentials.gid, ua_sess->tracing_id, + app->uid); if (ret < 0) { /* * reg_pid->registry->reg.ust is NULL upon error, so we need to @@ -2015,7 +2074,8 @@ static int setup_buffer_reg_uid(struct ltt_ust_session *usess, app->uint64_t_alignment, app->long_alignment, app->byte_order, app->version.major, app->version.minor, reg_uid->root_shm_path, - reg_uid->shm_path, usess->uid, usess->gid); + reg_uid->shm_path, usess->uid, usess->gid, + ua_sess->tracing_id, app->uid); if (ret < 0) { /* * reg_uid->registry->reg.ust is NULL upon error, so we need to @@ -2052,7 +2112,7 @@ error: * Returns 0 on success or else a negative code which is either -ENOMEM or * -ENOTCONN which is the default code if the ustctl_create_session fails. */ -static int create_ust_app_session(struct ltt_ust_session *usess, +static int find_or_create_ust_app_session(struct ltt_ust_session *usess, struct ust_app *app, struct ust_app_session **ua_sess_ptr, int *is_created) { @@ -2069,7 +2129,7 @@ static int create_ust_app_session(struct ltt_ust_session *usess, if (ua_sess == NULL) { DBG2("UST app pid: %d session id %" PRIu64 " not found, creating it", app->pid, usess->id); - ua_sess = alloc_ust_app_session(app); + ua_sess = alloc_ust_app_session(); if (ua_sess == NULL) { /* Only malloc can failed so something is really wrong */ ret = -ENOMEM; @@ -2139,6 +2199,9 @@ static int create_ust_app_session(struct ltt_ust_session *usess, lttng_ht_node_init_u64(&ua_sess->node, ua_sess->tracing_id); lttng_ht_add_unique_u64(app->sessions, &ua_sess->node); + lttng_ht_node_init_ulong(&ua_sess->ust_objd_node, ua_sess->handle); + lttng_ht_add_unique_ulong(app->ust_sessions_objd, + &ua_sess->ust_objd_node); DBG2("UST app session created successfully with handle %d", ret); } @@ -2165,7 +2228,7 @@ error: static int ht_match_ust_app_ctx(struct cds_lfht_node *node, const void *_key) { struct ust_app_ctx *ctx; - const struct lttng_ust_context *key; + const struct lttng_ust_context_attr *key; assert(node); assert(_key); @@ -2178,13 +2241,24 @@ static int ht_match_ust_app_ctx(struct cds_lfht_node *node, const void *_key) goto no_match; } - /* Check the name in the case of perf thread counters. */ - if (key->ctx == LTTNG_UST_CONTEXT_PERF_THREAD_COUNTER) { + switch(key->ctx) { + case LTTNG_UST_CONTEXT_PERF_THREAD_COUNTER: if (strncmp(key->u.perf_counter.name, - ctx->ctx.u.perf_counter.name, - sizeof(key->u.perf_counter.name))) { + ctx->ctx.u.perf_counter.name, + sizeof(key->u.perf_counter.name))) { + goto no_match; + } + break; + case LTTNG_UST_CONTEXT_APP_CONTEXT: + if (strcmp(key->u.app_ctx.provider_name, + ctx->ctx.u.app_ctx.provider_name) || + strcmp(key->u.app_ctx.ctx_name, + ctx->ctx.u.app_ctx.ctx_name)) { goto no_match; } + break; + default: + break; } /* Match. */ @@ -2202,7 +2276,7 @@ no_match: */ static struct ust_app_ctx *find_ust_app_context(struct lttng_ht *ht, - struct lttng_ust_context *uctx) + struct lttng_ust_context_attr *uctx) { struct lttng_ht_iter iter; struct lttng_ht_node_ulong *node; @@ -2231,8 +2305,8 @@ end: * Called with UST app session lock held and a RCU read side lock. */ static -int create_ust_app_channel_context(struct ust_app_session *ua_sess, - struct ust_app_channel *ua_chan, struct lttng_ust_context *uctx, +int create_ust_app_channel_context(struct ust_app_channel *ua_chan, + struct lttng_ust_context_attr *uctx, struct ust_app *app) { int ret = 0; @@ -2249,7 +2323,7 @@ int create_ust_app_channel_context(struct ust_app_session *ua_sess, ua_ctx = alloc_ust_app_ctx(uctx); if (ua_ctx == NULL) { /* malloc failed */ - ret = -1; + ret = -ENOMEM; goto error; } @@ -2361,11 +2435,14 @@ error: /* * Ask the consumer to create a channel and get it if successful. * + * Called with UST app session lock held. + * * Return 0 on success or else a negative value. */ static int do_consumer_create_channel(struct ltt_ust_session *usess, struct ust_app_session *ua_sess, struct ust_app_channel *ua_chan, - int bitness, struct ust_registry_session *registry) + int bitness, struct ust_registry_session *registry, + uint64_t trace_archive_id) { int ret; unsigned int nb_fd = 0; @@ -2400,7 +2477,7 @@ static int do_consumer_create_channel(struct ltt_ust_session *usess, * stream we have to expect. */ ret = ust_consumer_ask_channel(ua_sess, ua_chan, usess->consumer, socket, - registry); + registry, usess->current_trace_chunk); if (ret < 0) { goto error_ask; } @@ -2706,9 +2783,6 @@ static int send_channel_uid_to_ust(struct buffer_reg_channel *reg_chan, (void) release_ust_app_stream(-1, &stream, app); if (ret == -EPIPE || ret == -LTTNG_UST_ERR_EXITING) { ret = -ENOTCONN; /* Caused by app exiting. */ - goto error_stream_unlock; - } else if (ret < 0) { - goto error_stream_unlock; } goto error_stream_unlock; } @@ -2730,6 +2804,9 @@ error: /* * Create and send to the application the created buffers with per UID buffers. * + * This MUST be called with a RCU read side lock acquired. + * The session list lock and the session's lock must be acquired. + * * Return 0 on success else a negative value. */ static int create_channel_per_uid(struct ust_app *app, @@ -2739,6 +2816,9 @@ static int create_channel_per_uid(struct ust_app *app, int ret; struct buffer_reg_uid *reg_uid; struct buffer_reg_channel *reg_chan; + struct ltt_session *session = NULL; + enum lttng_error_code notification_ret; + struct ust_registry_channel *chan_reg; assert(app); assert(usess); @@ -2757,50 +2837,77 @@ static int create_channel_per_uid(struct ust_app *app, reg_chan = buffer_reg_channel_find(ua_chan->tracing_channel_id, reg_uid); - if (!reg_chan) { - /* Create the buffer registry channel object. */ - ret = create_buffer_reg_channel(reg_uid->registry, ua_chan, ®_chan); - if (ret < 0) { - ERR("Error creating the UST channel \"%s\" registry instance", - ua_chan->name); - goto error; - } - assert(reg_chan); + if (reg_chan) { + goto send_channel; + } - /* - * Create the buffers on the consumer side. This call populates the - * ust app channel object with all streams and data object. - */ - ret = do_consumer_create_channel(usess, ua_sess, ua_chan, - app->bits_per_long, reg_uid->registry->reg.ust); - if (ret < 0) { - ERR("Error creating UST channel \"%s\" on the consumer daemon", + /* Create the buffer registry channel object. */ + ret = create_buffer_reg_channel(reg_uid->registry, ua_chan, ®_chan); + if (ret < 0) { + ERR("Error creating the UST channel \"%s\" registry instance", ua_chan->name); + goto error; + } - /* - * Let's remove the previously created buffer registry channel so - * it's not visible anymore in the session registry. - */ - ust_registry_channel_del_free(reg_uid->registry->reg.ust, - ua_chan->tracing_channel_id); - buffer_reg_channel_remove(reg_uid->registry, reg_chan); - buffer_reg_channel_destroy(reg_chan, LTTNG_DOMAIN_UST); - goto error; - } + session = session_find_by_id(ua_sess->tracing_id); + assert(session); + assert(pthread_mutex_trylock(&session->lock)); + assert(session_trylock_list()); + + /* + * Create the buffers on the consumer side. This call populates the + * ust app channel object with all streams and data object. + */ + ret = do_consumer_create_channel(usess, ua_sess, ua_chan, + app->bits_per_long, reg_uid->registry->reg.ust, + session->most_recent_chunk_id.value); + if (ret < 0) { + ERR("Error creating UST channel \"%s\" on the consumer daemon", + ua_chan->name); /* - * Setup the streams and add it to the session registry. + * Let's remove the previously created buffer registry channel so + * it's not visible anymore in the session registry. */ - ret = setup_buffer_reg_channel(reg_uid->registry, - ua_chan, reg_chan, app); - if (ret < 0) { - ERR("Error setting up UST channel \"%s\"", - ua_chan->name); - goto error; - } + ust_registry_channel_del_free(reg_uid->registry->reg.ust, + ua_chan->tracing_channel_id, false); + buffer_reg_channel_remove(reg_uid->registry, reg_chan); + buffer_reg_channel_destroy(reg_chan, LTTNG_DOMAIN_UST); + goto error; + } + + /* + * Setup the streams and add it to the session registry. + */ + ret = setup_buffer_reg_channel(reg_uid->registry, + ua_chan, reg_chan, app); + if (ret < 0) { + ERR("Error setting up UST channel \"%s\"", ua_chan->name); + goto error; + } + /* Notify the notification subsystem of the channel's creation. */ + pthread_mutex_lock(®_uid->registry->reg.ust->lock); + chan_reg = ust_registry_channel_find(reg_uid->registry->reg.ust, + ua_chan->tracing_channel_id); + assert(chan_reg); + chan_reg->consumer_key = ua_chan->key; + chan_reg = NULL; + pthread_mutex_unlock(®_uid->registry->reg.ust->lock); + + notification_ret = notification_thread_command_add_channel( + notification_thread_handle, session->name, + ua_sess->effective_credentials.uid, + ua_sess->effective_credentials.gid, ua_chan->name, + ua_chan->key, LTTNG_DOMAIN_UST, + ua_chan->attr.subbuf_size * ua_chan->attr.num_subbuf); + if (notification_ret != LTTNG_OK) { + ret = - (int) notification_ret; + ERR("Failed to add channel to notification thread"); + goto error; } +send_channel: /* Send buffers to the application. */ ret = send_channel_uid_to_ust(reg_chan, app, ua_sess, ua_chan); if (ret < 0) { @@ -2811,12 +2918,18 @@ static int create_channel_per_uid(struct ust_app *app, } error: + if (session) { + session_put(session); + } return ret; } /* * Create and send to the application the created buffers with per PID buffers. * + * Called with UST app session lock held. + * The session list lock and the session's lock must be acquired. + * * Return 0 on success else a negative value. */ static int create_channel_per_pid(struct ust_app *app, @@ -2825,6 +2938,10 @@ static int create_channel_per_pid(struct ust_app *app, { int ret; struct ust_registry_session *registry; + enum lttng_error_code cmd_ret; + struct ltt_session *session = NULL; + uint64_t chan_reg_key; + struct ust_registry_channel *chan_reg; assert(app); assert(usess); @@ -2836,6 +2953,7 @@ static int create_channel_per_pid(struct ust_app *app, rcu_read_lock(); registry = get_session_registry(ua_sess); + /* The UST app session lock is held, registry shall not be null. */ assert(registry); /* Create and add a new channel registry to session. */ @@ -2846,13 +2964,20 @@ static int create_channel_per_pid(struct ust_app *app, goto error; } + session = session_find_by_id(ua_sess->tracing_id); + assert(session); + + assert(pthread_mutex_trylock(&session->lock)); + assert(session_trylock_list()); + /* Create and get channel on the consumer side. */ ret = do_consumer_create_channel(usess, ua_sess, ua_chan, - app->bits_per_long, registry); + app->bits_per_long, registry, + session->most_recent_chunk_id.value); if (ret < 0) { ERR("Error creating UST channel \"%s\" on the consumer daemon", ua_chan->name); - goto error; + goto error_remove_from_registry; } ret = send_channel_pid_to_ust(app, ua_sess, ua_chan); @@ -2860,23 +2985,51 @@ static int create_channel_per_pid(struct ust_app *app, if (ret != -ENOTCONN) { ERR("Error sending channel to application"); } - goto error; + goto error_remove_from_registry; + } + + chan_reg_key = ua_chan->key; + pthread_mutex_lock(®istry->lock); + chan_reg = ust_registry_channel_find(registry, chan_reg_key); + assert(chan_reg); + chan_reg->consumer_key = ua_chan->key; + pthread_mutex_unlock(®istry->lock); + + cmd_ret = notification_thread_command_add_channel( + notification_thread_handle, session->name, + ua_sess->effective_credentials.uid, + ua_sess->effective_credentials.gid, ua_chan->name, + ua_chan->key, LTTNG_DOMAIN_UST, + ua_chan->attr.subbuf_size * ua_chan->attr.num_subbuf); + if (cmd_ret != LTTNG_OK) { + ret = - (int) cmd_ret; + ERR("Failed to add channel to notification thread"); + goto error_remove_from_registry; } +error_remove_from_registry: + if (ret) { + ust_registry_channel_del_free(registry, ua_chan->key, false); + } error: rcu_read_unlock(); + if (session) { + session_put(session); + } return ret; } /* * From an already allocated ust app channel, create the channel buffers if - * need and send it to the application. This MUST be called with a RCU read + * needed and send them to the application. This MUST be called with a RCU read * side lock acquired. * + * Called with UST app session lock held. + * * Return 0 on success or else a negative value. Returns -ENOTCONN if * the application exited concurrently. */ -static int do_create_channel(struct ust_app *app, +static int ust_app_channel_send(struct ust_app *app, struct ltt_ust_session *usess, struct ust_app_session *ua_sess, struct ust_app_channel *ua_chan) { @@ -2884,6 +3037,7 @@ static int do_create_channel(struct ust_app *app, assert(app); assert(usess); + assert(usess->active); assert(ua_sess); assert(ua_chan); @@ -2928,16 +3082,14 @@ error: } /* - * Create UST app channel and create it on the tracer. Set ua_chanp of the - * newly created channel if not NULL. + * Create UST app channel and return it through ua_chanp if not NULL. * * Called with UST app session lock and RCU read-side lock held. * - * Return 0 on success or else a negative value. Returns -ENOTCONN if - * the application exited concurrently. + * Return 0 on success or else a negative value. */ -static int create_ust_app_channel(struct ust_app_session *ua_sess, - struct ltt_ust_channel *uchan, struct ust_app *app, +static int ust_app_channel_allocate(struct ust_app_session *ua_sess, + struct ltt_ust_channel *uchan, enum lttng_ust_chan_type type, struct ltt_ust_session *usess, struct ust_app_channel **ua_chanp) { @@ -2958,24 +3110,15 @@ static int create_ust_app_channel(struct ust_app_session *ua_sess, if (ua_chan == NULL) { /* Only malloc can fail here */ ret = -ENOMEM; - goto error_alloc; + goto error; } shadow_copy_channel(ua_chan, uchan); /* Set channel type. */ ua_chan->attr.type = type; - ret = do_create_channel(app, usess, ua_sess, ua_chan); - if (ret < 0) { - goto error; - } - - DBG2("UST app create channel %s for PID %d completed", ua_chan->name, - app->pid); - /* Only add the channel if successful on the tracer side. */ lttng_ht_add_unique_str(ua_sess->channels, &ua_chan->node); - end: if (ua_chanp) { *ua_chanp = ua_chan; @@ -2985,8 +3128,6 @@ end: return 0; error: - delete_ust_app_channel(ua_chan->is_sent ? app->sock : -1, ua_chan, app); -error_alloc: return ret; } @@ -3003,18 +3144,9 @@ int create_ust_app_event(struct ust_app_session *ua_sess, int ret = 0; struct ust_app_event *ua_event; - /* Get event node */ - ua_event = find_ust_app_event(ua_chan->events, uevent->attr.name, - uevent->filter, uevent->attr.loglevel, uevent->exclusion); - if (ua_event != NULL) { - ret = -EEXIST; - goto end; - } - - /* Does not exist so create one */ ua_event = alloc_ust_app_event(uevent->attr.name, &uevent->attr); if (ua_event == NULL) { - /* Only malloc can failed so something is really wrong */ + /* Only failure mode of alloc_ust_app_event(). */ ret = -ENOMEM; goto end; } @@ -3023,8 +3155,19 @@ int create_ust_app_event(struct ust_app_session *ua_sess, /* Create it on the tracer side */ ret = create_ust_event(app, ua_sess, ua_chan, ua_event); if (ret < 0) { - /* Not found previously means that it does not exist on the tracer */ - assert(ret != -LTTNG_UST_ERR_EXIST); + /* + * Not found previously means that it does not exist on the + * tracer. If the application reports that the event existed, + * it means there is a bug in the sessiond or lttng-ust + * (or corruption, etc.) + */ + if (ret == -LTTNG_UST_ERR_EXIST) { + ERR("Tracer for application reported that an event being created already existed: " + "event_name = \"%s\", pid = %d, ppid = %d, uid = %d, gid = %d", + uevent->attr.name, + app->pid, app->ppid, app->uid, + app->gid); + } goto error; } @@ -3054,12 +3197,14 @@ static int create_ust_app_metadata(struct ust_app_session *ua_sess, struct ust_app_channel *metadata; struct consumer_socket *socket; struct ust_registry_session *registry; + struct ltt_session *session = NULL; assert(ua_sess); assert(app); assert(consumer); registry = get_session_registry(ua_sess); + /* The UST app session is held registry shall not be null. */ assert(registry); pthread_mutex_lock(®istry->lock); @@ -3102,6 +3247,12 @@ static int create_ust_app_metadata(struct ust_app_session *ua_sess, */ registry->metadata_key = metadata->key; + session = session_find_by_id(ua_sess->tracing_id); + assert(session); + + assert(pthread_mutex_trylock(&session->lock)); + assert(session_trylock_list()); + /* * Ask the metadata channel creation to the consumer. The metadata object * will be created by the consumer and kept their. However, the stream is @@ -3109,7 +3260,7 @@ static int create_ust_app_metadata(struct ust_app_session *ua_sess, * consumer. */ ret = ust_consumer_ask_channel(ua_sess, metadata, consumer, socket, - registry); + registry, session->current_trace_chunk); if (ret < 0) { /* Nullify the metadata key so we don't try to close it later on. */ registry->metadata_key = 0; @@ -3137,6 +3288,9 @@ error_consumer: delete_ust_app_channel(-1, metadata, app); error: pthread_mutex_unlock(®istry->lock); + if (session) { + session_put(session); + } return ret; } @@ -3213,6 +3367,7 @@ struct ust_app *ust_app_create(struct ust_register_msg *msg, int sock) lta->v_minor = msg->minor; lta->sessions = lttng_ht_new(0, LTTNG_HT_TYPE_U64); lta->ust_objd = lttng_ht_new(0, LTTNG_HT_TYPE_ULONG); + lta->ust_sessions_objd = lttng_ht_new(0, LTTNG_HT_TYPE_ULONG); lta->notify_sock = -1; /* Copy name and make sure it's NULL terminated. */ @@ -3245,6 +3400,8 @@ void ust_app_add(struct ust_app *app) assert(app); assert(app->notify_sock >= 0); + app->registration_time = time(NULL); + rcu_read_lock(); /* @@ -3393,8 +3550,8 @@ void ust_app_unregister(int sock) /* * Remove application from notify hash table. The thread handling the * notify socket could have deleted the node so ignore on error because - * either way it's valid. The close of that socket is handled by the other - * thread. + * either way it's valid. The close of that socket is handled by the + * apps_notify_thread. */ iter.iter.node = <a->notify_sock_n.node; (void) lttng_ht_del(ust_app_ht_by_notify_sock, &iter); @@ -3482,7 +3639,9 @@ int ust_app_list_events(struct lttng_event **events) } free(tmp_event); release_ret = ustctl_release_handle(app->sock, handle); - if (release_ret != -LTTNG_UST_ERR_EXITING && release_ret != -EPIPE) { + if (release_ret < 0 && + release_ret != -LTTNG_UST_ERR_EXITING && + release_ret != -EPIPE) { ERR("Error releasing app handle for app %d with ret %d", app->sock, release_ret); } pthread_mutex_unlock(&app->sock_lock); @@ -3507,7 +3666,9 @@ int ust_app_list_events(struct lttng_event **events) free(tmp_event); ret = -ENOMEM; release_ret = ustctl_release_handle(app->sock, handle); - if (release_ret != -LTTNG_UST_ERR_EXITING && release_ret != -EPIPE) { + if (release_ret < 0 && + release_ret != -LTTNG_UST_ERR_EXITING && + release_ret != -EPIPE) { ERR("Error releasing app handle for app %d with ret %d", app->sock, release_ret); } pthread_mutex_unlock(&app->sock_lock); @@ -3528,7 +3689,7 @@ int ust_app_list_events(struct lttng_event **events) } ret = ustctl_release_handle(app->sock, handle); pthread_mutex_unlock(&app->sock_lock); - if (ret != -LTTNG_UST_ERR_EXITING && ret != -EPIPE) { + if (ret < 0 && ret != -LTTNG_UST_ERR_EXITING && ret != -EPIPE) { ERR("Error releasing app handle for app %d with ret %d", app->sock, ret); } } @@ -3610,7 +3771,9 @@ int ust_app_list_event_fields(struct lttng_event_field **fields) free(tmp_event); release_ret = ustctl_release_handle(app->sock, handle); pthread_mutex_unlock(&app->sock_lock); - if (release_ret != -LTTNG_UST_ERR_EXITING && release_ret != -EPIPE) { + if (release_ret < 0 && + release_ret != -LTTNG_UST_ERR_EXITING && + release_ret != -EPIPE) { ERR("Error releasing app handle for app %d with ret %d", app->sock, release_ret); } goto rcu_error; @@ -3635,7 +3798,9 @@ int ust_app_list_event_fields(struct lttng_event_field **fields) ret = -ENOMEM; release_ret = ustctl_release_handle(app->sock, handle); pthread_mutex_unlock(&app->sock_lock); - if (release_ret != -LTTNG_UST_ERR_EXITING && release_ret != -EPIPE) { + if (release_ret && + release_ret != -LTTNG_UST_ERR_EXITING && + release_ret != -EPIPE) { ERR("Error releasing app handle for app %d with ret %d", app->sock, release_ret); } goto rcu_error; @@ -3661,7 +3826,9 @@ int ust_app_list_event_fields(struct lttng_event_field **fields) } ret = ustctl_release_handle(app->sock, handle); pthread_mutex_unlock(&app->sock_lock); - if (ret != -LTTNG_UST_ERR_EXITING && ret != -EPIPE) { + if (ret < 0 && + ret != -LTTNG_UST_ERR_EXITING && + ret != -EPIPE) { ERR("Error releasing app handle for app %d with ret %d", app->sock, ret); } } @@ -3693,6 +3860,24 @@ void ust_app_clean_list(void) rcu_read_lock(); + /* Cleanup notify socket hash table */ + if (ust_app_ht_by_notify_sock) { + cds_lfht_for_each_entry(ust_app_ht_by_notify_sock->ht, &iter.iter, app, + notify_sock_n.node) { + struct cds_lfht_node *node; + struct ust_app *app; + + node = cds_lfht_iter_get_node(&iter.iter); + if (!node) { + continue; + } + + app = container_of(node, struct ust_app, + notify_sock_n.node); + ust_app_notify_sock_unregister(app->notify_sock); + } + } + if (ust_app_ht) { cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) { ret = lttng_ht_del(ust_app_ht, &iter); @@ -3710,14 +3895,6 @@ void ust_app_clean_list(void) } } - /* Cleanup notify socket hash table */ - if (ust_app_ht_by_notify_sock) { - cds_lfht_for_each_entry(ust_app_ht_by_notify_sock->ht, &iter.iter, app, - notify_sock_n.node) { - ret = lttng_ht_del(ust_app_ht_by_notify_sock, &iter); - assert(!ret); - } - } rcu_read_unlock(); /* Destroy is done only when the ht is empty */ @@ -3765,12 +3942,7 @@ int ust_app_disable_channel_glb(struct ltt_ust_session *usess, struct ust_app_session *ua_sess; struct ust_app_channel *ua_chan; - if (usess == NULL || uchan == NULL) { - ERR("Disabling UST global channel with NULL values"); - ret = -1; - goto error; - } - + assert(usess->active); DBG2("UST app disabling channel %s from global domain for session id %" PRIu64, uchan->name, usess->id); @@ -3810,8 +3982,6 @@ int ust_app_disable_channel_glb(struct ltt_ust_session *usess, } rcu_read_unlock(); - -error: return ret; } @@ -3826,12 +3996,7 @@ int ust_app_enable_channel_glb(struct ltt_ust_session *usess, struct ust_app *app; struct ust_app_session *ua_sess; - if (usess == NULL || uchan == NULL) { - ERR("Adding UST global channel to NULL values"); - ret = -1; - goto error; - } - + assert(usess->active); DBG2("UST app enabling channel %s to global domain for session id %" PRIu64, uchan->name, usess->id); @@ -3860,8 +4025,6 @@ int ust_app_enable_channel_glb(struct ltt_ust_session *usess, } rcu_read_unlock(); - -error: return ret; } @@ -3873,12 +4036,13 @@ int ust_app_disable_event_glb(struct ltt_ust_session *usess, { int ret = 0; struct lttng_ht_iter iter, uiter; - struct lttng_ht_node_str *ua_chan_node, *ua_event_node; + struct lttng_ht_node_str *ua_chan_node; struct ust_app *app; struct ust_app_session *ua_sess; struct ust_app_channel *ua_chan; struct ust_app_event *ua_event; + assert(usess->active); DBG("UST app disabling event %s for all apps in channel " "%s for session id %" PRIu64, uevent->attr.name, uchan->name, usess->id); @@ -3910,14 +4074,14 @@ int ust_app_disable_event_glb(struct ltt_ust_session *usess, } ua_chan = caa_container_of(ua_chan_node, struct ust_app_channel, node); - lttng_ht_lookup(ua_chan->events, (void *)uevent->attr.name, &uiter); - ua_event_node = lttng_ht_iter_get_node_str(&uiter); - if (ua_event_node == NULL) { + ua_event = find_ust_app_event(ua_chan->events, uevent->attr.name, + uevent->filter, uevent->attr.loglevel, + uevent->exclusion); + if (ua_event == NULL) { DBG2("Event %s not found in channel %s for app pid %d." "Skipping", uevent->attr.name, uchan->name, app->pid); continue; } - ua_event = caa_container_of(ua_event_node, struct ust_app_event, node); ret = disable_ust_app_event(ua_sess, ua_event, app); if (ret < 0) { @@ -3927,107 +4091,77 @@ int ust_app_disable_event_glb(struct ltt_ust_session *usess, } rcu_read_unlock(); - return ret; } -/* - * For a specific UST session, create the channel for all registered apps. - */ -int ust_app_create_channel_glb(struct ltt_ust_session *usess, - struct ltt_ust_channel *uchan) +/* The ua_sess lock must be held by the caller. */ +static +int ust_app_channel_create(struct ltt_ust_session *usess, + struct ust_app_session *ua_sess, + struct ltt_ust_channel *uchan, struct ust_app *app, + struct ust_app_channel **_ua_chan) { - int ret = 0, created; - struct lttng_ht_iter iter; - struct ust_app *app; - struct ust_app_session *ua_sess = NULL; + int ret = 0; + struct ust_app_channel *ua_chan = NULL; - /* Very wrong code flow */ - assert(usess); - assert(uchan); - - DBG2("UST app adding channel %s to UST domain for session id %" PRIu64, - uchan->name, usess->id); - - rcu_read_lock(); + assert(ua_sess); + ASSERT_LOCKED(ua_sess->lock); - /* For every registered applications */ - cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) { - if (!app->compatible) { - /* - * TODO: In time, we should notice the caller of this error by - * telling him that this is a version error. - */ - continue; - } - if (!trace_ust_pid_tracker_lookup(usess, app->pid)) { - /* Skip. */ - continue; - } + if (!strncmp(uchan->name, DEFAULT_METADATA_NAME, + sizeof(uchan->name))) { + copy_channel_attr_to_ustctl(&ua_sess->metadata_attr, + &uchan->attr); + ret = 0; + } else { + struct ltt_ust_context *uctx = NULL; /* - * Create session on the tracer side and add it to app session HT. Note - * that if session exist, it will simply return a pointer to the ust - * app session. + * Create channel onto application and synchronize its + * configuration. */ - ret = create_ust_app_session(usess, app, &ua_sess, &created); - if (ret < 0) { - switch (ret) { - case -ENOTCONN: - /* - * The application's socket is not valid. Either a bad socket - * or a timeout on it. We can't inform the caller that for a - * specific app, the session failed so lets continue here. - */ - ret = 0; /* Not an error. */ - continue; - case -ENOMEM: - default: - goto error_rcu_unlock; - } - } - assert(ua_sess); - - pthread_mutex_lock(&ua_sess->lock); - - if (ua_sess->deleted) { - pthread_mutex_unlock(&ua_sess->lock); - continue; - } - - if (!strncmp(uchan->name, DEFAULT_METADATA_NAME, - sizeof(uchan->name))) { - copy_channel_attr_to_ustctl(&ua_sess->metadata_attr, &uchan->attr); - ret = 0; + ret = ust_app_channel_allocate(ua_sess, uchan, + LTTNG_UST_CHAN_PER_CPU, usess, + &ua_chan); + if (ret == 0) { + ret = ust_app_channel_send(app, usess, + ua_sess, ua_chan); } else { - /* Create channel onto application. We don't need the chan ref. */ - ret = create_ust_app_channel(ua_sess, uchan, app, - LTTNG_UST_CHAN_PER_CPU, usess, NULL); + goto end; } - pthread_mutex_unlock(&ua_sess->lock); - if (ret < 0) { - /* Cleanup the created session if it's the case. */ - if (created) { - destroy_app_session(app, ua_sess); - } - switch (ret) { - case -ENOTCONN: - /* - * The application's socket is not valid. Either a bad socket - * or a timeout on it. We can't inform the caller that for a - * specific app, the session failed so lets continue here. - */ - ret = 0; /* Not an error. */ - continue; - case -ENOMEM: - default: - goto error_rcu_unlock; + + /* Add contexts. */ + cds_list_for_each_entry(uctx, &uchan->ctx_list, list) { + ret = create_ust_app_channel_context(ua_chan, + &uctx->ctx, app); + if (ret) { + goto end; } } } - -error_rcu_unlock: - rcu_read_unlock(); + if (ret < 0) { + switch (ret) { + case -ENOTCONN: + /* + * The application's socket is not valid. Either a bad socket + * or a timeout on it. We can't inform the caller that for a + * specific app, the session failed so lets continue here. + */ + ret = 0; /* Not an error. */ + break; + case -ENOMEM: + default: + break; + } + } +end: + if (ret == 0 && _ua_chan) { + /* + * Only return the application's channel on success. Note + * that the channel can still be part of the application's + * channel hashtable on error. + */ + *_ua_chan = ua_chan; + } return ret; } @@ -4045,6 +4179,7 @@ int ust_app_enable_event_glb(struct ltt_ust_session *usess, struct ust_app_channel *ua_chan; struct ust_app_event *ua_event; + assert(usess->active); DBG("UST app enabling event %s for all apps for session id %" PRIu64, uevent->attr.name, usess->id); @@ -4130,6 +4265,7 @@ int ust_app_create_event_glb(struct ltt_ust_session *usess, struct ust_app_session *ua_sess; struct ust_app_channel *ua_chan; + assert(usess->active); DBG("UST app creating event %s for all apps for session id %" PRIu64, uevent->attr.name, usess->id); @@ -4179,12 +4315,14 @@ int ust_app_create_event_glb(struct ltt_ust_session *usess, } rcu_read_unlock(); - return ret; } /* * Start tracing for a specific UST session and app. + * + * Called with UST app session lock held. + * */ static int ust_app_start_trace(struct ltt_ust_session *usess, struct ust_app *app) @@ -4213,24 +4351,16 @@ int ust_app_start_trace(struct ltt_ust_session *usess, struct ust_app *app) goto end; } + if (ua_sess->enabled) { + pthread_mutex_unlock(&ua_sess->lock); + goto end; + } + /* Upon restart, we skip the setup, already done */ if (ua_sess->started) { goto skip_setup; } - /* Create directories if consumer is LOCAL and has a path defined. */ - if (usess->consumer->type == CONSUMER_DST_LOCAL && - strlen(usess->consumer->dst.trace_path) > 0) { - ret = run_as_mkdir_recursive(usess->consumer->dst.trace_path, - S_IRWXU | S_IRWXG, ua_sess->euid, ua_sess->egid); - if (ret < 0) { - if (errno != EEXIST) { - ERR("Trace directory creation error"); - goto error_unlock; - } - } - } - /* * Create the metadata for the application. This returns gracefully if a * metadata was already set for the session. @@ -4243,7 +4373,7 @@ int ust_app_start_trace(struct ltt_ust_session *usess, struct ust_app *app) health_code_update(); skip_setup: - /* This start the UST tracing */ + /* This starts the UST tracing */ pthread_mutex_lock(&app->sock_lock); ret = ustctl_start_session(app->sock, ua_sess->handle); pthread_mutex_unlock(&app->sock_lock); @@ -4266,6 +4396,7 @@ skip_setup: /* Indicate that the session has been started once */ ua_sess->started = 1; + ua_sess->enabled = 1; pthread_mutex_unlock(&ua_sess->lock); @@ -4355,6 +4486,7 @@ int ust_app_stop_trace(struct ltt_ust_session *usess, struct ust_app *app) } health_code_update(); + ua_sess->enabled = 0; /* Quiescent wait after stopping trace */ pthread_mutex_lock(&app->sock_lock); @@ -4368,6 +4500,8 @@ int ust_app_stop_trace(struct ltt_ust_session *usess, struct ust_app *app) health_code_update(); registry = get_session_registry(ua_sess); + + /* The UST app session is held registry shall not be null. */ assert(registry); /* Push metadata for application before freeing the application. */ @@ -4422,7 +4556,6 @@ int ust_app_flush_app_session(struct ust_app *app, cds_lfht_for_each_entry(ua_sess->channels->ht, &iter.iter, ua_chan, node.node) { health_code_update(); - assert(ua_chan->is_sent); ret = consumer_flush_channel(socket, ua_chan->key); if (ret) { ERR("Error flushing consumer channel"); @@ -4525,6 +4658,155 @@ int ust_app_flush_session(struct ltt_ust_session *usess) return ret; } +static +int ust_app_clear_quiescent_app_session(struct ust_app *app, + struct ust_app_session *ua_sess) +{ + int ret = 0; + struct lttng_ht_iter iter; + struct ust_app_channel *ua_chan; + struct consumer_socket *socket; + + DBG("Clearing stream quiescent state for ust app pid %d", app->pid); + + rcu_read_lock(); + + if (!app->compatible) { + goto end_not_compatible; + } + + pthread_mutex_lock(&ua_sess->lock); + + if (ua_sess->deleted) { + goto end_unlock; + } + + health_code_update(); + + socket = consumer_find_socket_by_bitness(app->bits_per_long, + ua_sess->consumer); + if (!socket) { + ERR("Failed to find consumer (%" PRIu32 ") socket", + app->bits_per_long); + ret = -1; + goto end_unlock; + } + + /* Clear quiescent state. */ + switch (ua_sess->buffer_type) { + case LTTNG_BUFFER_PER_PID: + cds_lfht_for_each_entry(ua_sess->channels->ht, &iter.iter, + ua_chan, node.node) { + health_code_update(); + ret = consumer_clear_quiescent_channel(socket, + ua_chan->key); + if (ret) { + ERR("Error clearing quiescent state for consumer channel"); + ret = -1; + continue; + } + } + break; + case LTTNG_BUFFER_PER_UID: + default: + assert(0); + ret = -1; + break; + } + + health_code_update(); + +end_unlock: + pthread_mutex_unlock(&ua_sess->lock); + +end_not_compatible: + rcu_read_unlock(); + health_code_update(); + return ret; +} + +/* + * Clear quiescent state in each stream for all applications for a + * specific UST session. + * Called with UST session lock held. + */ +static +int ust_app_clear_quiescent_session(struct ltt_ust_session *usess) + +{ + int ret = 0; + + DBG("Clearing stream quiescent state for all ust apps"); + + rcu_read_lock(); + + switch (usess->buffer_type) { + case LTTNG_BUFFER_PER_UID: + { + struct lttng_ht_iter iter; + struct buffer_reg_uid *reg; + + /* + * Clear quiescent for all per UID buffers associated to + * that session. + */ + cds_list_for_each_entry(reg, &usess->buffer_reg_uid_list, lnode) { + struct consumer_socket *socket; + struct buffer_reg_channel *reg_chan; + + /* Get associated consumer socket.*/ + socket = consumer_find_socket_by_bitness( + reg->bits_per_long, usess->consumer); + if (!socket) { + /* + * Ignore request if no consumer is found for + * the session. + */ + continue; + } + + cds_lfht_for_each_entry(reg->registry->channels->ht, + &iter.iter, reg_chan, node.node) { + /* + * The following call will print error values so + * the return code is of little importance + * because whatever happens, we have to try them + * all. + */ + (void) consumer_clear_quiescent_channel(socket, + reg_chan->consumer_key); + } + } + break; + } + case LTTNG_BUFFER_PER_PID: + { + struct ust_app_session *ua_sess; + struct lttng_ht_iter iter; + struct ust_app *app; + + cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, + pid_n.node) { + ua_sess = lookup_session_by_app(usess, app); + if (ua_sess == NULL) { + continue; + } + (void) ust_app_clear_quiescent_app_session(app, + ua_sess); + } + break; + } + default: + ret = -1; + assert(0); + break; + } + + rcu_read_unlock(); + health_code_update(); + return ret; +} + /* * Destroy a specific UST session in apps. */ @@ -4575,20 +4857,29 @@ end: */ int ust_app_start_trace_all(struct ltt_ust_session *usess) { - int ret = 0; struct lttng_ht_iter iter; struct ust_app *app; DBG("Starting all UST traces"); + /* + * Even though the start trace might fail, flag this session active so + * other application coming in are started by default. + */ + usess->active = 1; + rcu_read_lock(); + /* + * In a start-stop-start use-case, we need to clear the quiescent state + * of each channel set by the prior stop command, thus ensuring that a + * following stop or destroy is sure to grab a timestamp_end near those + * operations, even if the packet is empty. + */ + (void) ust_app_clear_quiescent_session(usess); + cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) { - ret = ust_app_start_trace(usess, app); - if (ret < 0) { - /* Continue to next apps even on error */ - continue; - } + ust_app_global_update(usess, app); } rcu_read_unlock(); @@ -4608,6 +4899,12 @@ int ust_app_stop_trace_all(struct ltt_ust_session *usess) DBG("Stopping all UST traces"); + /* + * Even though the stop trace might fail, flag this session inactive so + * other application coming in are not started by default. + */ + usess->active = 0; + rcu_read_lock(); cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) { @@ -4651,92 +4948,147 @@ int ust_app_destroy_trace_all(struct ltt_ust_session *usess) return 0; } +/* The ua_sess lock must be held by the caller. */ static -void ust_app_global_create(struct ltt_ust_session *usess, struct ust_app *app) +int find_or_create_ust_app_channel( + struct ltt_ust_session *usess, + struct ust_app_session *ua_sess, + struct ust_app *app, + struct ltt_ust_channel *uchan, + struct ust_app_channel **ua_chan) { int ret = 0; - struct lttng_ht_iter iter, uiter; - struct ust_app_session *ua_sess = NULL; - struct ust_app_channel *ua_chan; - struct ust_app_event *ua_event; - struct ust_app_ctx *ua_ctx; - int is_created = 0; + struct lttng_ht_iter iter; + struct lttng_ht_node_str *ua_chan_node; - ret = create_ust_app_session(usess, app, &ua_sess, &is_created); - if (ret < 0) { - /* Tracer is probably gone or ENOMEM. */ - goto error; - } - if (!is_created) { - /* App session already created. */ + lttng_ht_lookup(ua_sess->channels, (void *) uchan->name, &iter); + ua_chan_node = lttng_ht_iter_get_node_str(&iter); + if (ua_chan_node) { + *ua_chan = caa_container_of(ua_chan_node, + struct ust_app_channel, node); goto end; } - assert(ua_sess); - - pthread_mutex_lock(&ua_sess->lock); - if (ua_sess->deleted) { - pthread_mutex_unlock(&ua_sess->lock); + ret = ust_app_channel_create(usess, ua_sess, uchan, app, ua_chan); + if (ret) { goto end; } +end: + return ret; +} - /* - * We can iterate safely here over all UST app session since the create ust - * app session above made a shadow copy of the UST global domain from the - * ltt ust session. - */ - cds_lfht_for_each_entry(ua_sess->channels->ht, &iter.iter, ua_chan, - node.node) { - ret = do_create_channel(app, usess, ua_sess, ua_chan); - if (ret < 0 && ret != -ENOTCONN) { - /* - * Stop everything. On error, the application - * failed, no more file descriptor are available - * or ENOMEM so stopping here is the only thing - * we can do for now. The only exception is - * -ENOTCONN, which indicates that the application - * has exit. - */ - goto error_unlock; - } +static +int ust_app_channel_synchronize_event(struct ust_app_channel *ua_chan, + struct ltt_ust_event *uevent, struct ust_app_session *ua_sess, + struct ust_app *app) +{ + int ret = 0; + struct ust_app_event *ua_event = NULL; - /* - * Add context using the list so they are enabled in the same order the - * user added them. - */ - cds_list_for_each_entry(ua_ctx, &ua_chan->ctx_list, list) { - ret = create_ust_channel_context(ua_chan, ua_ctx, app); - if (ret < 0) { - goto error_unlock; - } + ua_event = find_ust_app_event(ua_chan->events, uevent->attr.name, + uevent->filter, uevent->attr.loglevel, uevent->exclusion); + if (!ua_event) { + ret = create_ust_app_event(ua_sess, ua_chan, uevent, app); + if (ret < 0) { + goto end; + } + } else { + if (ua_event->enabled != uevent->enabled) { + ret = uevent->enabled ? + enable_ust_app_event(ua_sess, ua_event, app) : + disable_ust_app_event(ua_sess, ua_event, app); } + } +end: + return ret; +} - /* For each events */ - cds_lfht_for_each_entry(ua_chan->events->ht, &uiter.iter, ua_event, +/* + * The caller must ensure that the application is compatible and is tracked + * by the PID tracker. + */ +static +void ust_app_synchronize(struct ltt_ust_session *usess, + struct ust_app *app) +{ + int ret = 0; + struct cds_lfht_iter uchan_iter; + struct ltt_ust_channel *uchan; + struct ust_app_session *ua_sess = NULL; + + /* + * The application's configuration should only be synchronized for + * active sessions. + */ + assert(usess->active); + + ret = find_or_create_ust_app_session(usess, app, &ua_sess, NULL); + if (ret < 0) { + /* Tracer is probably gone or ENOMEM. */ + goto error; + } + assert(ua_sess); + + pthread_mutex_lock(&ua_sess->lock); + if (ua_sess->deleted) { + pthread_mutex_unlock(&ua_sess->lock); + goto end; + } + + rcu_read_lock(); + cds_lfht_for_each_entry(usess->domain_global.channels->ht, &uchan_iter, + uchan, node.node) { + struct ust_app_channel *ua_chan; + struct cds_lfht_iter uevent_iter; + struct ltt_ust_event *uevent; + + /* + * Search for a matching ust_app_channel. If none is found, + * create it. Creating the channel will cause the ua_chan + * structure to be allocated, the channel buffers to be + * allocated (if necessary) and sent to the application, and + * all enabled contexts will be added to the channel. + */ + ret = find_or_create_ust_app_channel(usess, ua_sess, + app, uchan, &ua_chan); + if (ret) { + /* Tracer is probably gone or ENOMEM. */ + goto error_unlock; + } + + if (!ua_chan) { + /* ua_chan will be NULL for the metadata channel */ + continue; + } + + cds_lfht_for_each_entry(uchan->events->ht, &uevent_iter, uevent, node.node) { - ret = create_ust_event(app, ua_sess, ua_chan, ua_event); - if (ret < 0) { + ret = ust_app_channel_synchronize_event(ua_chan, + uevent, ua_sess, app); + if (ret) { goto error_unlock; } } - } - - pthread_mutex_unlock(&ua_sess->lock); - if (usess->active) { - ret = ust_app_start_trace(usess, app); - if (ret < 0) { - goto error; + if (ua_chan->enabled != uchan->enabled) { + ret = uchan->enabled ? + enable_ust_app_channel(ua_sess, uchan, app) : + disable_ust_app_channel(ua_sess, ua_chan, app); + if (ret) { + goto error_unlock; + } } - - DBG2("UST trace started for app pid %d", app->pid); } + rcu_read_unlock(); + end: + pthread_mutex_unlock(&ua_sess->lock); /* Everything went well at this point. */ return; error_unlock: + rcu_read_unlock(); pthread_mutex_unlock(&ua_sess->lock); error: if (ua_sess) { @@ -4766,6 +5118,7 @@ void ust_app_global_destroy(struct ltt_ust_session *usess, struct ust_app *app) void ust_app_global_update(struct ltt_ust_session *usess, struct ust_app *app) { assert(usess); + assert(usess->active); DBG2("UST app global update for app sock %d for session id %" PRIu64, app->sock, usess->id); @@ -4773,9 +5126,17 @@ void ust_app_global_update(struct ltt_ust_session *usess, struct ust_app *app) if (!app->compatible) { return; } - - if (trace_ust_pid_tracker_lookup(usess, app->pid)) { - ust_app_global_create(usess, app); + if (trace_ust_id_tracker_lookup(LTTNG_TRACKER_VPID, usess, app->pid) && + trace_ust_id_tracker_lookup( + LTTNG_TRACKER_VUID, usess, app->uid) && + trace_ust_id_tracker_lookup( + LTTNG_TRACKER_VGID, usess, app->gid)) { + /* + * Synchronize the application's internal tracing configuration + * and start tracing. + */ + ust_app_synchronize(usess, app); + ust_app_start_trace(usess, app); } else { ust_app_global_destroy(usess, app); } @@ -4809,8 +5170,9 @@ int ust_app_add_ctx_channel_glb(struct ltt_ust_session *usess, struct ust_app_session *ua_sess; struct ust_app *app; - rcu_read_lock(); + assert(usess->active); + rcu_read_lock(); cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) { if (!app->compatible) { /* @@ -4839,7 +5201,7 @@ int ust_app_add_ctx_channel_glb(struct ltt_ust_session *usess, } ua_chan = caa_container_of(ua_chan_node, struct ust_app_channel, node); - ret = create_ust_app_channel_context(ua_sess, ua_chan, &uctx->ctx, app); + ret = create_ust_app_channel_context(ua_chan, &uctx->ctx, app); if (ret < 0) { goto next_app; } @@ -4851,127 +5213,6 @@ int ust_app_add_ctx_channel_glb(struct ltt_ust_session *usess, return ret; } -/* - * Enable event for a channel from a UST session for a specific PID. - */ -int ust_app_enable_event_pid(struct ltt_ust_session *usess, - struct ltt_ust_channel *uchan, struct ltt_ust_event *uevent, pid_t pid) -{ - int ret = 0; - struct lttng_ht_iter iter; - struct lttng_ht_node_str *ua_chan_node; - struct ust_app *app; - struct ust_app_session *ua_sess; - struct ust_app_channel *ua_chan; - struct ust_app_event *ua_event; - - DBG("UST app enabling event %s for PID %d", uevent->attr.name, pid); - - rcu_read_lock(); - - app = ust_app_find_by_pid(pid); - if (app == NULL) { - ERR("UST app enable event per PID %d not found", pid); - ret = -1; - goto end; - } - - if (!app->compatible) { - ret = 0; - goto end; - } - - ua_sess = lookup_session_by_app(usess, app); - if (!ua_sess) { - /* The application has problem or is probably dead. */ - ret = 0; - goto end; - } - - pthread_mutex_lock(&ua_sess->lock); - - if (ua_sess->deleted) { - ret = 0; - goto end_unlock; - } - - /* Lookup channel in the ust app session */ - lttng_ht_lookup(ua_sess->channels, (void *)uchan->name, &iter); - ua_chan_node = lttng_ht_iter_get_node_str(&iter); - /* If the channel is not found, there is a code flow error */ - assert(ua_chan_node); - - ua_chan = caa_container_of(ua_chan_node, struct ust_app_channel, node); - - ua_event = find_ust_app_event(ua_chan->events, uevent->attr.name, - uevent->filter, uevent->attr.loglevel, uevent->exclusion); - if (ua_event == NULL) { - ret = create_ust_app_event(ua_sess, ua_chan, uevent, app); - if (ret < 0) { - goto end_unlock; - } - } else { - ret = enable_ust_app_event(ua_sess, ua_event, app); - if (ret < 0) { - goto end_unlock; - } - } - -end_unlock: - pthread_mutex_unlock(&ua_sess->lock); -end: - rcu_read_unlock(); - return ret; -} - -/* - * Calibrate registered applications. - */ -int ust_app_calibrate_glb(struct lttng_ust_calibrate *calibrate) -{ - int ret = 0; - struct lttng_ht_iter iter; - struct ust_app *app; - - rcu_read_lock(); - - cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) { - if (!app->compatible) { - /* - * TODO: In time, we should notice the caller of this error by - * telling him that this is a version error. - */ - continue; - } - - health_code_update(); - - pthread_mutex_lock(&app->sock_lock); - ret = ustctl_calibrate(app->sock, calibrate); - pthread_mutex_unlock(&app->sock_lock); - if (ret < 0) { - switch (ret) { - case -ENOSYS: - /* Means that it's not implemented on the tracer side. */ - ret = 0; - break; - default: - DBG2("Calibrate app PID %d returned with error %d", - app->pid, ret); - break; - } - } - } - - DBG("UST app global domain calibration finished"); - - rcu_read_unlock(); - - health_code_update(); - - return ret; -} - /* * Receive registration and populate the given msg structure. * @@ -5021,6 +5262,33 @@ error: return ret; } +/* + * Return a ust app session object using the application object and the + * session object descriptor has a key. If not found, NULL is returned. + * A RCU read side lock MUST be acquired when calling this function. +*/ +static struct ust_app_session *find_session_by_objd(struct ust_app *app, + int objd) +{ + struct lttng_ht_node_ulong *node; + struct lttng_ht_iter iter; + struct ust_app_session *ua_sess = NULL; + + assert(app); + + lttng_ht_lookup(app->ust_sessions_objd, (void *)((unsigned long) objd), &iter); + node = lttng_ht_iter_get_node_ulong(&iter); + if (node == NULL) { + DBG2("UST app session find by objd %d not found", objd); + goto error; + } + + ua_sess = caa_container_of(node, struct ust_app_session, ust_objd_node); + +error: + return ua_sess; +} + /* * Return a ust app channel object using the application object and the channel * object descriptor has a key. If not found, NULL is returned. A RCU read side @@ -5056,11 +5324,11 @@ error: * * On success 0 is returned else a negative value. */ -static int reply_ust_register_channel(int sock, int sobjd, int cobjd, +static int reply_ust_register_channel(int sock, int cobjd, size_t nr_fields, struct ustctl_field *fields) { int ret, ret_code = 0; - uint32_t chan_id, reg_count; + uint32_t chan_id; uint64_t chan_reg_key; enum ustctl_channel_header type; struct ust_app *app; @@ -5074,19 +5342,17 @@ static int reply_ust_register_channel(int sock, int sobjd, int cobjd, /* Lookup application. If not found, there is a code flow error. */ app = find_app_by_notify_sock(sock); if (!app) { - DBG("Application socket %d is being teardown. Abort event notify", + DBG("Application socket %d is being torn down. Abort event notify", sock); ret = 0; - free(fields); goto error_rcu_unlock; } /* Lookup channel by UST object descriptor. */ ua_chan = find_channel_by_objd(app, cobjd); if (!ua_chan) { - DBG("Application channel is being teardown. Abort event notify"); + DBG("Application channel is being torn down. Abort event notify"); ret = 0; - free(fields); goto error_rcu_unlock; } @@ -5095,7 +5361,11 @@ static int reply_ust_register_channel(int sock, int sobjd, int cobjd, /* Get right session registry depending on the session buffer type. */ registry = get_session_registry(ua_sess); - assert(registry); + if (!registry) { + DBG("Application session is being torn down. Abort event notify"); + ret = 0; + goto error_rcu_unlock; + }; /* Depending on the buffer type, a different channel key is used. */ if (ua_sess->buffer_type == LTTNG_BUFFER_PER_UID) { @@ -5110,22 +5380,19 @@ static int reply_ust_register_channel(int sock, int sobjd, int cobjd, assert(chan_reg); if (!chan_reg->register_done) { - reg_count = ust_registry_get_event_count(chan_reg); - if (reg_count < 31) { - type = USTCTL_CHANNEL_HEADER_COMPACT; - } else { - type = USTCTL_CHANNEL_HEADER_LARGE; - } - + /* + * TODO: eventually use the registry event count for + * this channel to better guess header type for per-pid + * buffers. + */ + type = USTCTL_CHANNEL_HEADER_LARGE; chan_reg->nr_ctx_fields = nr_fields; chan_reg->ctx_fields = fields; + fields = NULL; chan_reg->header_type = type; } else { /* Get current already assigned values. */ type = chan_reg->header_type; - free(fields); - /* Set to NULL so the error path does not do a double free. */ - fields = NULL; } /* Channel id is set during the object creation. */ chan_id = chan_reg->chan_id; @@ -5161,9 +5428,7 @@ error: pthread_mutex_unlock(®istry->lock); error_rcu_unlock: rcu_read_unlock(); - if (ret) { - free(fields); - } + free(fields); return ret; } @@ -5193,23 +5458,17 @@ static int add_event_ust_registry(int sock, int sobjd, int cobjd, char *name, /* Lookup application. If not found, there is a code flow error. */ app = find_app_by_notify_sock(sock); if (!app) { - DBG("Application socket %d is being teardown. Abort event notify", + DBG("Application socket %d is being torn down. Abort event notify", sock); ret = 0; - free(sig); - free(fields); - free(model_emf_uri); goto error_rcu_unlock; } /* Lookup channel by UST object descriptor. */ ua_chan = find_channel_by_objd(app, cobjd); if (!ua_chan) { - DBG("Application channel is being teardown. Abort event notify"); + DBG("Application channel is being torn down. Abort event notify"); ret = 0; - free(sig); - free(fields); - free(model_emf_uri); goto error_rcu_unlock; } @@ -5217,7 +5476,11 @@ static int add_event_ust_registry(int sock, int sobjd, int cobjd, char *name, ua_sess = ua_chan->session; registry = get_session_registry(ua_sess); - assert(registry); + if (!registry) { + DBG("Application session is being torn down. Abort event notify"); + ret = 0; + goto error_rcu_unlock; + } if (ua_sess->buffer_type == LTTNG_BUFFER_PER_UID) { chan_reg_key = ua_chan->tracing_channel_id; @@ -5236,6 +5499,9 @@ static int add_event_ust_registry(int sock, int sobjd, int cobjd, char *name, sobjd, cobjd, name, sig, nr_fields, fields, loglevel_value, model_emf_uri, ua_sess->buffer_type, &event_id, app); + sig = NULL; + fields = NULL; + model_emf_uri = NULL; /* * The return value is returned to ustctl so in case of an error, the @@ -5259,6 +5525,93 @@ static int add_event_ust_registry(int sock, int sobjd, int cobjd, char *name, DBG3("UST registry event %s with id %" PRId32 " added successfully", name, event_id); +error: + pthread_mutex_unlock(®istry->lock); +error_rcu_unlock: + rcu_read_unlock(); + free(sig); + free(fields); + free(model_emf_uri); + return ret; +} + +/* + * Add enum to the UST session registry. Once done, this replies to the + * application with the appropriate error code. + * + * The session UST registry lock is acquired within this function. + * + * On success 0 is returned else a negative value. + */ +static int add_enum_ust_registry(int sock, int sobjd, char *name, + struct ustctl_enum_entry *entries, size_t nr_entries) +{ + int ret = 0, ret_code; + struct ust_app *app; + struct ust_app_session *ua_sess; + struct ust_registry_session *registry; + uint64_t enum_id = -1ULL; + + rcu_read_lock(); + + /* Lookup application. If not found, there is a code flow error. */ + app = find_app_by_notify_sock(sock); + if (!app) { + /* Return an error since this is not an error */ + DBG("Application socket %d is being torn down. Aborting enum registration", + sock); + free(entries); + goto error_rcu_unlock; + } + + /* Lookup session by UST object descriptor. */ + ua_sess = find_session_by_objd(app, sobjd); + if (!ua_sess) { + /* Return an error since this is not an error */ + DBG("Application session is being torn down (session not found). Aborting enum registration."); + free(entries); + goto error_rcu_unlock; + } + + registry = get_session_registry(ua_sess); + if (!registry) { + DBG("Application session is being torn down (registry not found). Aborting enum registration."); + free(entries); + goto error_rcu_unlock; + } + + pthread_mutex_lock(®istry->lock); + + /* + * From this point on, the callee acquires the ownership of + * entries. The variable entries MUST NOT be read/written after + * call. + */ + ret_code = ust_registry_create_or_find_enum(registry, sobjd, name, + entries, nr_entries, &enum_id); + entries = NULL; + + /* + * The return value is returned to ustctl so in case of an error, the + * application can be notified. In case of an error, it's important not to + * return a negative error or else the application will get closed. + */ + ret = ustctl_reply_register_enum(sock, enum_id, ret_code); + if (ret < 0) { + if (ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) { + ERR("UST app reply enum failed with ret %d", ret); + } else { + DBG3("UST app reply enum failed. Application died"); + } + /* + * No need to wipe the create enum since the application socket will + * get close on error hence cleaning up everything by itself. + */ + goto error; + } + + DBG3("UST registry enum %s added successfully or already found", name); + error: pthread_mutex_unlock(®istry->lock); error_rcu_unlock: @@ -5348,7 +5701,7 @@ int ust_app_recv_notify(int sock) * that if needed it will be freed. After this, it's invalid to access * fields or clean it up. */ - ret = reply_ust_register_channel(sock, sobjd, cobjd, nr_fields, + ret = reply_ust_register_channel(sock, cobjd, nr_fields, fields); if (ret < 0) { goto error; @@ -5356,10 +5709,39 @@ int ust_app_recv_notify(int sock) break; } - default: - /* Should NEVER happen. */ - assert(0); - } + case USTCTL_NOTIFY_CMD_ENUM: + { + int sobjd; + char name[LTTNG_UST_SYM_NAME_LEN]; + size_t nr_entries; + struct ustctl_enum_entry *entries; + + DBG2("UST app ustctl register enum received"); + + ret = ustctl_recv_register_enum(sock, &sobjd, name, + &entries, &nr_entries); + if (ret < 0) { + if (ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) { + ERR("UST app recv enum failed with ret %d", ret); + } else { + DBG3("UST app recv enum failed. Application died"); + } + goto error; + } + + /* Callee assumes ownership of entries */ + ret = add_enum_ust_registry(sock, sobjd, name, + entries, nr_entries); + if (ret < 0) { + goto error; + } + + break; + } + default: + /* Should NEVER happen. */ + assert(0); + } error: return ret; @@ -5458,17 +5840,18 @@ void ust_app_destroy(struct ust_app *app) * Take a snapshot for a given UST session. The snapshot is sent to the given * output. * - * Return 0 on success or else a negative value. + * Returns LTTNG_OK on success or a LTTNG_ERR error code. */ -int ust_app_snapshot_record(struct ltt_ust_session *usess, - struct snapshot_output *output, int wait, +enum lttng_error_code ust_app_snapshot_record( + const struct ltt_ust_session *usess, + const struct consumer_output *output, int wait, uint64_t nb_packets_per_stream) { int ret = 0; - unsigned int snapshot_done = 0; + enum lttng_error_code status = LTTNG_OK; struct lttng_ht_iter iter; struct ust_app *app; - char pathname[PATH_MAX]; + char *trace_path = NULL; assert(usess); assert(output); @@ -5483,12 +5866,19 @@ int ust_app_snapshot_record(struct ltt_ust_session *usess, cds_list_for_each_entry(reg, &usess->buffer_reg_uid_list, lnode) { struct buffer_reg_channel *reg_chan; struct consumer_socket *socket; + char pathname[PATH_MAX]; + size_t consumer_path_offset = 0; + + if (!reg->registry->reg.ust->metadata_key) { + /* Skip since no metadata is present */ + continue; + } /* Get consumer socket to use to push the metadata.*/ socket = consumer_find_socket_by_bitness(reg->bits_per_long, usess->consumer); if (!socket) { - ret = -EINVAL; + status = LTTNG_ERR_INVALID; goto error; } @@ -5498,26 +5888,36 @@ int ust_app_snapshot_record(struct ltt_ust_session *usess, reg->uid, reg->bits_per_long); if (ret < 0) { PERROR("snprintf snapshot path"); + status = LTTNG_ERR_INVALID; goto error; } - - /* Add the UST default trace dir to path. */ + /* Free path allowed on previous iteration. */ + free(trace_path); + trace_path = setup_channel_trace_path(usess->consumer, pathname, + &consumer_path_offset); + if (!trace_path) { + status = LTTNG_ERR_INVALID; + goto error; + } + /* Add the UST default trace dir to path. */ cds_lfht_for_each_entry(reg->registry->channels->ht, &iter.iter, reg_chan, node.node) { - ret = consumer_snapshot_channel(socket, reg_chan->consumer_key, - output, 0, usess->uid, usess->gid, pathname, wait, + status = consumer_snapshot_channel(socket, + reg_chan->consumer_key, + output, 0, usess->uid, + usess->gid, &trace_path[consumer_path_offset], wait, nb_packets_per_stream); - if (ret < 0) { + if (status != LTTNG_OK) { goto error; } } - ret = consumer_snapshot_channel(socket, + status = consumer_snapshot_channel(socket, reg->registry->reg.ust->metadata_key, output, 1, - usess->uid, usess->gid, pathname, wait, 0); - if (ret < 0) { + usess->uid, usess->gid, &trace_path[consumer_path_offset], + wait, 0); + if (status != LTTNG_OK) { goto error; } - snapshot_done = 1; } break; } @@ -5529,6 +5929,8 @@ int ust_app_snapshot_record(struct ltt_ust_session *usess, struct ust_app_channel *ua_chan; struct ust_app_session *ua_sess; struct ust_registry_session *registry; + char pathname[PATH_MAX]; + size_t consumer_path_offset = 0; ua_sess = lookup_session_by_app(usess, app); if (!ua_sess) { @@ -5538,9 +5940,9 @@ int ust_app_snapshot_record(struct ltt_ust_session *usess, /* Get the right consumer socket for the application. */ socket = consumer_find_socket_by_bitness(app->bits_per_long, - output->consumer); + output); if (!socket) { - ret = -EINVAL; + status = LTTNG_ERR_INVALID; goto error; } @@ -5549,28 +5951,56 @@ int ust_app_snapshot_record(struct ltt_ust_session *usess, ret = snprintf(pathname, sizeof(pathname), DEFAULT_UST_TRACE_DIR "/%s", ua_sess->path); if (ret < 0) { + status = LTTNG_ERR_INVALID; PERROR("snprintf snapshot path"); goto error; } - - cds_lfht_for_each_entry(ua_sess->channels->ht, &chan_iter.iter, + /* Free path allowed on previous iteration. */ + free(trace_path); + trace_path = setup_channel_trace_path(usess->consumer, pathname, + &consumer_path_offset); + if (!trace_path) { + status = LTTNG_ERR_INVALID; + goto error; + } + cds_lfht_for_each_entry(ua_sess->channels->ht, &chan_iter.iter, ua_chan, node.node) { - ret = consumer_snapshot_channel(socket, ua_chan->key, output, - 0, ua_sess->euid, ua_sess->egid, pathname, wait, + status = consumer_snapshot_channel(socket, + ua_chan->key, output, 0, + ua_sess->effective_credentials + .uid, + ua_sess->effective_credentials + .gid, + &trace_path[consumer_path_offset], wait, nb_packets_per_stream); - if (ret < 0) { + switch (status) { + case LTTNG_OK: + break; + case LTTNG_ERR_CHAN_NOT_FOUND: + continue; + default: goto error; } } registry = get_session_registry(ua_sess); - assert(registry); - ret = consumer_snapshot_channel(socket, registry->metadata_key, output, - 1, ua_sess->euid, ua_sess->egid, pathname, wait, 0); - if (ret < 0) { + if (!registry) { + DBG("Application session is being torn down. Skip application."); + continue; + } + status = consumer_snapshot_channel(socket, + registry->metadata_key, output, 1, + ua_sess->effective_credentials.uid, + ua_sess->effective_credentials.gid, + &trace_path[consumer_path_offset], wait, 0); + switch (status) { + case LTTNG_OK: + break; + case LTTNG_ERR_CHAN_NOT_FOUND: + continue; + default: goto error; } - snapshot_done = 1; } break; } @@ -5579,25 +6009,17 @@ int ust_app_snapshot_record(struct ltt_ust_session *usess, break; } - if (!snapshot_done) { - /* - * If no snapshot was made and we are not in the error path, this means - * that there are no buffers thus no (prior) application to snapshot - * data from so we have simply NO data. - */ - ret = -ENODATA; - } - error: + free(trace_path); rcu_read_unlock(); - return ret; + return status; } /* * Return the size taken by one more packet per stream. */ -uint64_t ust_app_get_size_one_more_packet_per_stream(struct ltt_ust_session *usess, - uint64_t cur_nr_packets) +uint64_t ust_app_get_size_one_more_packet_per_stream( + const struct ltt_ust_session *usess, uint64_t cur_nr_packets) { uint64_t tot_size = 0; struct ust_app *app; @@ -5665,3 +6087,562 @@ uint64_t ust_app_get_size_one_more_packet_per_stream(struct ltt_ust_session *use return tot_size; } + +int ust_app_uid_get_channel_runtime_stats(uint64_t ust_session_id, + struct cds_list_head *buffer_reg_uid_list, + struct consumer_output *consumer, uint64_t uchan_id, + int overwrite, uint64_t *discarded, uint64_t *lost) +{ + int ret; + uint64_t consumer_chan_key; + + *discarded = 0; + *lost = 0; + + ret = buffer_reg_uid_consumer_channel_key( + buffer_reg_uid_list, uchan_id, &consumer_chan_key); + if (ret < 0) { + /* Not found */ + ret = 0; + goto end; + } + + if (overwrite) { + ret = consumer_get_lost_packets(ust_session_id, + consumer_chan_key, consumer, lost); + } else { + ret = consumer_get_discarded_events(ust_session_id, + consumer_chan_key, consumer, discarded); + } + +end: + return ret; +} + +int ust_app_pid_get_channel_runtime_stats(struct ltt_ust_session *usess, + struct ltt_ust_channel *uchan, + struct consumer_output *consumer, int overwrite, + uint64_t *discarded, uint64_t *lost) +{ + int ret = 0; + struct lttng_ht_iter iter; + struct lttng_ht_node_str *ua_chan_node; + struct ust_app *app; + struct ust_app_session *ua_sess; + struct ust_app_channel *ua_chan; + + *discarded = 0; + *lost = 0; + + rcu_read_lock(); + /* + * Iterate over every registered applications. Sum counters for + * all applications containing requested session and channel. + */ + cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) { + struct lttng_ht_iter uiter; + + ua_sess = lookup_session_by_app(usess, app); + if (ua_sess == NULL) { + continue; + } + + /* Get channel */ + lttng_ht_lookup(ua_sess->channels, (void *) uchan->name, &uiter); + ua_chan_node = lttng_ht_iter_get_node_str(&uiter); + /* If the session is found for the app, the channel must be there */ + assert(ua_chan_node); + + ua_chan = caa_container_of(ua_chan_node, struct ust_app_channel, node); + + if (overwrite) { + uint64_t _lost; + + ret = consumer_get_lost_packets(usess->id, ua_chan->key, + consumer, &_lost); + if (ret < 0) { + break; + } + (*lost) += _lost; + } else { + uint64_t _discarded; + + ret = consumer_get_discarded_events(usess->id, + ua_chan->key, consumer, &_discarded); + if (ret < 0) { + break; + } + (*discarded) += _discarded; + } + } + + rcu_read_unlock(); + return ret; +} + +static +int ust_app_regenerate_statedump(struct ltt_ust_session *usess, + struct ust_app *app) +{ + int ret = 0; + struct ust_app_session *ua_sess; + + DBG("Regenerating the metadata for ust app pid %d", app->pid); + + rcu_read_lock(); + + ua_sess = lookup_session_by_app(usess, app); + if (ua_sess == NULL) { + /* The session is in teardown process. Ignore and continue. */ + goto end; + } + + pthread_mutex_lock(&ua_sess->lock); + + if (ua_sess->deleted) { + goto end_unlock; + } + + pthread_mutex_lock(&app->sock_lock); + ret = ustctl_regenerate_statedump(app->sock, ua_sess->handle); + pthread_mutex_unlock(&app->sock_lock); + +end_unlock: + pthread_mutex_unlock(&ua_sess->lock); + +end: + rcu_read_unlock(); + health_code_update(); + return ret; +} + +/* + * Regenerate the statedump for each app in the session. + */ +int ust_app_regenerate_statedump_all(struct ltt_ust_session *usess) +{ + int ret = 0; + struct lttng_ht_iter iter; + struct ust_app *app; + + DBG("Regenerating the metadata for all UST apps"); + + rcu_read_lock(); + + cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) { + if (!app->compatible) { + continue; + } + + ret = ust_app_regenerate_statedump(usess, app); + if (ret < 0) { + /* Continue to the next app even on error */ + continue; + } + } + + rcu_read_unlock(); + + return 0; +} + +/* + * Rotate all the channels of a session. + * + * Return LTTNG_OK on success or else an LTTng error code. + */ +enum lttng_error_code ust_app_rotate_session(struct ltt_session *session) +{ + int ret; + enum lttng_error_code cmd_ret = LTTNG_OK; + struct lttng_ht_iter iter; + struct ust_app *app; + struct ltt_ust_session *usess = session->ust_session; + + assert(usess); + + rcu_read_lock(); + + switch (usess->buffer_type) { + case LTTNG_BUFFER_PER_UID: + { + struct buffer_reg_uid *reg; + + cds_list_for_each_entry(reg, &usess->buffer_reg_uid_list, lnode) { + struct buffer_reg_channel *reg_chan; + struct consumer_socket *socket; + + if (!reg->registry->reg.ust->metadata_key) { + /* Skip since no metadata is present */ + continue; + } + + /* Get consumer socket to use to push the metadata.*/ + socket = consumer_find_socket_by_bitness(reg->bits_per_long, + usess->consumer); + if (!socket) { + cmd_ret = LTTNG_ERR_INVALID; + goto error; + } + + /* Rotate the data channels. */ + cds_lfht_for_each_entry(reg->registry->channels->ht, &iter.iter, + reg_chan, node.node) { + ret = consumer_rotate_channel(socket, + reg_chan->consumer_key, + usess->uid, usess->gid, + usess->consumer, + /* is_metadata_channel */ false); + if (ret < 0) { + cmd_ret = LTTNG_ERR_ROTATION_FAIL_CONSUMER; + goto error; + } + } + + (void) push_metadata(reg->registry->reg.ust, usess->consumer); + + ret = consumer_rotate_channel(socket, + reg->registry->reg.ust->metadata_key, + usess->uid, usess->gid, + usess->consumer, + /* is_metadata_channel */ true); + if (ret < 0) { + cmd_ret = LTTNG_ERR_ROTATION_FAIL_CONSUMER; + goto error; + } + } + break; + } + case LTTNG_BUFFER_PER_PID: + { + cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) { + struct consumer_socket *socket; + struct lttng_ht_iter chan_iter; + struct ust_app_channel *ua_chan; + struct ust_app_session *ua_sess; + struct ust_registry_session *registry; + + ua_sess = lookup_session_by_app(usess, app); + if (!ua_sess) { + /* Session not associated with this app. */ + continue; + } + + /* Get the right consumer socket for the application. */ + socket = consumer_find_socket_by_bitness(app->bits_per_long, + usess->consumer); + if (!socket) { + cmd_ret = LTTNG_ERR_INVALID; + goto error; + } + + registry = get_session_registry(ua_sess); + if (!registry) { + DBG("Application session is being torn down. Skip application."); + continue; + } + + /* Rotate the data channels. */ + cds_lfht_for_each_entry(ua_sess->channels->ht, &chan_iter.iter, + ua_chan, node.node) { + ret = consumer_rotate_channel(socket, + ua_chan->key, + ua_sess->effective_credentials + .uid, + ua_sess->effective_credentials + .gid, + ua_sess->consumer, + /* is_metadata_channel */ false); + if (ret < 0) { + /* Per-PID buffer and application going away. */ + if (ret == -LTTNG_ERR_CHAN_NOT_FOUND) + continue; + cmd_ret = LTTNG_ERR_ROTATION_FAIL_CONSUMER; + goto error; + } + } + + /* Rotate the metadata channel. */ + (void) push_metadata(registry, usess->consumer); + ret = consumer_rotate_channel(socket, + registry->metadata_key, + ua_sess->effective_credentials.uid, + ua_sess->effective_credentials.gid, + ua_sess->consumer, + /* is_metadata_channel */ true); + if (ret < 0) { + /* Per-PID buffer and application going away. */ + if (ret == -LTTNG_ERR_CHAN_NOT_FOUND) + continue; + cmd_ret = LTTNG_ERR_ROTATION_FAIL_CONSUMER; + goto error; + } + } + break; + } + default: + assert(0); + break; + } + + cmd_ret = LTTNG_OK; + +error: + rcu_read_unlock(); + return cmd_ret; +} + +enum lttng_error_code ust_app_create_channel_subdirectories( + const struct ltt_ust_session *usess) +{ + enum lttng_error_code ret = LTTNG_OK; + struct lttng_ht_iter iter; + enum lttng_trace_chunk_status chunk_status; + char *pathname_index; + int fmt_ret; + + assert(usess->current_trace_chunk); + rcu_read_lock(); + + switch (usess->buffer_type) { + case LTTNG_BUFFER_PER_UID: + { + struct buffer_reg_uid *reg; + + cds_list_for_each_entry(reg, &usess->buffer_reg_uid_list, lnode) { + fmt_ret = asprintf(&pathname_index, + DEFAULT_UST_TRACE_DIR "/" DEFAULT_UST_TRACE_UID_PATH "/" DEFAULT_INDEX_DIR, + reg->uid, reg->bits_per_long); + if (fmt_ret < 0) { + ERR("Failed to format channel index directory"); + ret = LTTNG_ERR_CREATE_DIR_FAIL; + goto error; + } + + /* + * Create the index subdirectory which will take care + * of implicitly creating the channel's path. + */ + chunk_status = lttng_trace_chunk_create_subdirectory( + usess->current_trace_chunk, + pathname_index); + free(pathname_index); + if (chunk_status != LTTNG_TRACE_CHUNK_STATUS_OK) { + ret = LTTNG_ERR_CREATE_DIR_FAIL; + goto error; + } + } + break; + } + case LTTNG_BUFFER_PER_PID: + { + struct ust_app *app; + + /* + * Create the toplevel ust/ directory in case no apps are running. + */ + chunk_status = lttng_trace_chunk_create_subdirectory( + usess->current_trace_chunk, + DEFAULT_UST_TRACE_DIR); + if (chunk_status != LTTNG_TRACE_CHUNK_STATUS_OK) { + ret = LTTNG_ERR_CREATE_DIR_FAIL; + goto error; + } + + cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, + pid_n.node) { + struct ust_app_session *ua_sess; + struct ust_registry_session *registry; + + ua_sess = lookup_session_by_app(usess, app); + if (!ua_sess) { + /* Session not associated with this app. */ + continue; + } + + registry = get_session_registry(ua_sess); + if (!registry) { + DBG("Application session is being torn down. Skip application."); + continue; + } + + fmt_ret = asprintf(&pathname_index, + DEFAULT_UST_TRACE_DIR "/%s/" DEFAULT_INDEX_DIR, + ua_sess->path); + if (fmt_ret < 0) { + ERR("Failed to format channel index directory"); + ret = LTTNG_ERR_CREATE_DIR_FAIL; + goto error; + } + /* + * Create the index subdirectory which will take care + * of implicitly creating the channel's path. + */ + chunk_status = lttng_trace_chunk_create_subdirectory( + usess->current_trace_chunk, + pathname_index); + free(pathname_index); + if (chunk_status != LTTNG_TRACE_CHUNK_STATUS_OK) { + ret = LTTNG_ERR_CREATE_DIR_FAIL; + goto error; + } + } + break; + } + default: + abort(); + } + + ret = LTTNG_OK; +error: + rcu_read_unlock(); + return ret; +} + +/* + * Clear all the channels of a session. + * + * Return LTTNG_OK on success or else an LTTng error code. + */ +enum lttng_error_code ust_app_clear_session(struct ltt_session *session) +{ + int ret; + enum lttng_error_code cmd_ret = LTTNG_OK; + struct lttng_ht_iter iter; + struct ust_app *app; + struct ltt_ust_session *usess = session->ust_session; + + assert(usess); + + rcu_read_lock(); + + if (usess->active) { + ERR("Expecting inactive session %s (%" PRIu64 ")", session->name, session->id); + cmd_ret = LTTNG_ERR_FATAL; + goto end; + } + + switch (usess->buffer_type) { + case LTTNG_BUFFER_PER_UID: + { + struct buffer_reg_uid *reg; + + cds_list_for_each_entry(reg, &usess->buffer_reg_uid_list, lnode) { + struct buffer_reg_channel *reg_chan; + struct consumer_socket *socket; + + /* Get consumer socket to use to push the metadata.*/ + socket = consumer_find_socket_by_bitness(reg->bits_per_long, + usess->consumer); + if (!socket) { + cmd_ret = LTTNG_ERR_INVALID; + goto error_socket; + } + + /* Clear the data channels. */ + cds_lfht_for_each_entry(reg->registry->channels->ht, &iter.iter, + reg_chan, node.node) { + ret = consumer_clear_channel(socket, + reg_chan->consumer_key); + if (ret < 0) { + goto error; + } + } + + (void) push_metadata(reg->registry->reg.ust, usess->consumer); + + /* + * 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, + reg->registry->reg.ust->metadata_key); + if (ret < 0) { + goto error; + } + } + break; + } + case LTTNG_BUFFER_PER_PID: + { + cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) { + struct consumer_socket *socket; + struct lttng_ht_iter chan_iter; + struct ust_app_channel *ua_chan; + struct ust_app_session *ua_sess; + struct ust_registry_session *registry; + + ua_sess = lookup_session_by_app(usess, app); + if (!ua_sess) { + /* Session not associated with this app. */ + continue; + } + + /* Get the right consumer socket for the application. */ + socket = consumer_find_socket_by_bitness(app->bits_per_long, + usess->consumer); + if (!socket) { + cmd_ret = LTTNG_ERR_INVALID; + goto error_socket; + } + + registry = get_session_registry(ua_sess); + if (!registry) { + DBG("Application session is being torn down. Skip application."); + continue; + } + + /* Clear the data channels. */ + cds_lfht_for_each_entry(ua_sess->channels->ht, &chan_iter.iter, + ua_chan, node.node) { + ret = consumer_clear_channel(socket, ua_chan->key); + if (ret < 0) { + /* Per-PID buffer and application going away. */ + if (ret == -LTTNG_ERR_CHAN_NOT_FOUND) { + continue; + } + goto error; + } + } + + (void) push_metadata(registry, usess->consumer); + + /* + * 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, registry->metadata_key); + if (ret < 0) { + /* Per-PID buffer and application going away. */ + if (ret == -LTTNG_ERR_CHAN_NOT_FOUND) { + continue; + } + goto error; + } + } + break; + } + default: + assert(0); + break; + } + + cmd_ret = LTTNG_OK; + goto end; + +error: + switch (-ret) { + case LTTCOMM_CONSUMERD_RELAYD_CLEAR_DISALLOWED: + cmd_ret = LTTNG_ERR_CLEAR_RELAY_DISALLOWED; + break; + default: + cmd_ret = LTTNG_ERR_CLEAR_FAIL_CONSUMER; + } + +error_socket: +end: + rcu_read_unlock(); + return cmd_ret; +}