X-Git-Url: https://git.lttng.org/?a=blobdiff_plain;ds=sidebyside;f=src%2Fbin%2Flttng-sessiond%2Fagent.c;h=77846b4f2251e7891d4f32b5ad196da4f4535f53;hb=HEAD;hp=e5978be5cef3ac24ecc7b7255cff563f87b13580;hpb=733c916573fb96d14ff36cc0a034c5b1ef7ef167;p=lttng-tools.git diff --git a/src/bin/lttng-sessiond/agent.c b/src/bin/lttng-sessiond/agent.c deleted file mode 100644 index e5978be5c..000000000 --- a/src/bin/lttng-sessiond/agent.c +++ /dev/null @@ -1,1449 +0,0 @@ -/* - * Copyright (C) 2013 David Goulet - * Copyright (C) 2016 Jérémie Galarneau - * - * SPDX-License-Identifier: GPL-2.0-only - * - */ - -#define _LGPL_SOURCE -#include -#include -#include - -#include -#include - -#include - -#include "agent.h" -#include "ust-app.h" -#include "utils.h" -#include "common/error.h" - -#define AGENT_RET_CODE_INDEX(code) (code - AGENT_RET_CODE_SUCCESS) - -/* - * Agent application context representation. - */ -struct agent_app_ctx { - char *provider_name; - char *ctx_name; - - /* agent_app_ctx are part of the agent app_ctx_list. */ - struct cds_list_head list_node; - - /* For call_rcu teardown. */ - struct rcu_head rcu_node; -}; - -/* - * Human readable agent return code. - */ -static const char *error_string_array[] = { - [ AGENT_RET_CODE_INDEX(AGENT_RET_CODE_SUCCESS) ] = "Success", - [ AGENT_RET_CODE_INDEX(AGENT_RET_CODE_INVALID) ] = "Invalid command", - [ AGENT_RET_CODE_INDEX(AGENT_RET_CODE_UNKNOWN_NAME) ] = "Unknown logger name", - - /* Last element */ - [ AGENT_RET_CODE_INDEX(AGENT_RET_CODE_NR) ] = "Unknown code", -}; - -static -void log_reply_code(uint32_t in_reply_ret_code) -{ - int level = PRINT_DBG3; - /* - * reply_ret_code and in_reply_ret_code are kept separate to have a - * sanitized value (used to retrieve the human readable string) and the - * original value which is logged as-is. - */ - uint32_t reply_ret_code = in_reply_ret_code; - - if (reply_ret_code < AGENT_RET_CODE_SUCCESS || - reply_ret_code >= AGENT_RET_CODE_NR) { - reply_ret_code = AGENT_RET_CODE_NR; - level = PRINT_ERR; - } - - LOG(level, "Agent replied with retcode: %s (%"PRIu32")", - error_string_array[AGENT_RET_CODE_INDEX( - reply_ret_code)], - in_reply_ret_code); -} - -/* - * Match function for the events hash table lookup by name. - */ -static int ht_match_event_by_name(struct cds_lfht_node *node, - const void *_key) -{ - struct agent_event *event; - const struct agent_ht_key *key; - - assert(node); - assert(_key); - - event = caa_container_of(node, struct agent_event, node.node); - key = _key; - - /* Match 1 elements of the key: name. */ - - /* Event name */ - if (strncmp(event->name, key->name, sizeof(event->name)) != 0) { - goto no_match; - } - /* Match. */ - return 1; - -no_match: - return 0; -} - -/* - * Match function for the events hash table lookup by name and loglevel. - */ -static int ht_match_event(struct cds_lfht_node *node, - const void *_key) -{ - struct agent_event *event; - const struct agent_ht_key *key; - int ll_match; - - assert(node); - assert(_key); - - event = caa_container_of(node, struct agent_event, node.node); - key = _key; - - /* Match 2 elements of the key: name and loglevel. */ - - /* Event name */ - if (strncmp(event->name, key->name, sizeof(event->name)) != 0) { - goto no_match; - } - - /* Event loglevel value and type. */ - ll_match = loglevels_match(event->loglevel_type, - event->loglevel_value, key->loglevel_type, - key->loglevel_value, LTTNG_EVENT_LOGLEVEL_ALL); - - if (!ll_match) { - goto no_match; - } - - /* Filter expression */ - if (!!event->filter_expression != !!key->filter_expression) { - /* One has a filter expression, the other does not */ - goto no_match; - } - - if (event->filter_expression) { - if (strncmp(event->filter_expression, key->filter_expression, - strlen(event->filter_expression)) != 0) { - goto no_match; - } - } - - return 1; - -no_match: - return 0; -} - -/* - * Add unique agent event based on the event name and loglevel. - */ -static void add_unique_agent_event(struct lttng_ht *ht, - struct agent_event *event) -{ - struct cds_lfht_node *node_ptr; - struct agent_ht_key key; - - assert(ht); - assert(ht->ht); - assert(event); - - key.name = event->name; - key.loglevel_value = event->loglevel_value; - key.loglevel_type = event->loglevel_type; - key.filter_expression = event->filter_expression; - - node_ptr = cds_lfht_add_unique(ht->ht, - ht->hash_fct(event->node.key, lttng_ht_seed), - ht_match_event, &key, &event->node.node); - assert(node_ptr == &event->node.node); -} - -/* - * URCU delayed agent event reclaim. - */ -static void destroy_event_agent_rcu(struct rcu_head *head) -{ - struct lttng_ht_node_str *node = - caa_container_of(head, struct lttng_ht_node_str, head); - struct agent_event *event = - caa_container_of(node, struct agent_event, node); - - agent_destroy_event(event); -} - -/* - * URCU delayed agent app reclaim. - */ -static void destroy_app_agent_rcu(struct rcu_head *head) -{ - struct lttng_ht_node_ulong *node = - caa_container_of(head, struct lttng_ht_node_ulong, head); - struct agent_app *app = - caa_container_of(node, struct agent_app, node); - - free(app); -} - -/* - * Communication with the agent. Send the message header to the given socket in - * big endian. - * - * Return 0 on success or else a negative errno message of sendmsg() op. - */ -static int send_header(struct lttcomm_sock *sock, uint64_t data_size, - uint32_t cmd, uint32_t cmd_version) -{ - int ret; - ssize_t size; - struct lttcomm_agent_hdr msg; - - assert(sock); - - memset(&msg, 0, sizeof(msg)); - msg.data_size = htobe64(data_size); - msg.cmd = htobe32(cmd); - msg.cmd_version = htobe32(cmd_version); - - size = sock->ops->sendmsg(sock, &msg, sizeof(msg), 0); - if (size < sizeof(msg)) { - ret = -errno; - goto error; - } - ret = 0; - -error: - return ret; -} - -/* - * Communication call with the agent. Send the payload to the given socket. The - * header MUST be sent prior to this call. - * - * Return 0 on success or else a negative errno value of sendmsg() op. - */ -static int send_payload(struct lttcomm_sock *sock, const void *data, - size_t size) -{ - int ret; - ssize_t len; - - assert(sock); - assert(data); - - len = sock->ops->sendmsg(sock, data, size, 0); - if (len < size) { - ret = -errno; - goto error; - } - ret = 0; - -error: - return ret; -} - -/* - * Communication call with the agent. Receive reply from the agent using the - * given socket. - * - * Return 0 on success or else a negative errno value from recvmsg() op. - */ -static int recv_reply(struct lttcomm_sock *sock, void *buf, size_t size) -{ - int ret; - ssize_t len; - - assert(sock); - assert(buf); - - len = sock->ops->recvmsg(sock, buf, size, 0); - if (len < size) { - ret = -errno; - goto error; - } - ret = 0; - -error: - return ret; -} - -/* - * Internal event listing for a given app. Populate events. - * - * Return number of element in the list or else a negative LTTNG_ERR* code. - * On success, the caller is responsible for freeing the memory - * allocated for "events". - */ -static ssize_t list_events(struct agent_app *app, struct lttng_event **events) -{ - int ret, i, len = 0, offset = 0; - uint32_t nb_event; - size_t data_size; - uint32_t reply_ret_code; - struct lttng_event *tmp_events = NULL; - struct lttcomm_agent_list_reply *reply = NULL; - struct lttcomm_agent_list_reply_hdr reply_hdr; - - assert(app); - assert(app->sock); - assert(events); - - DBG2("Agent listing events for app pid: %d and socket %d", app->pid, - app->sock->fd); - - ret = send_header(app->sock, 0, AGENT_CMD_LIST, 0); - if (ret < 0) { - goto error_io; - } - - /* Get list header so we know how much we'll receive. */ - ret = recv_reply(app->sock, &reply_hdr, sizeof(reply_hdr)); - if (ret < 0) { - goto error_io; - } - - reply_ret_code = be32toh(reply_hdr.ret_code); - log_reply_code(reply_ret_code); - switch (reply_ret_code) { - case AGENT_RET_CODE_SUCCESS: - data_size = be32toh(reply_hdr.data_size) + sizeof(*reply); - break; - default: - ret = LTTNG_ERR_UNK; - goto error; - } - - reply = zmalloc(data_size); - if (!reply) { - ret = LTTNG_ERR_NOMEM; - goto error; - } - - /* Get the list with the appropriate data size. */ - ret = recv_reply(app->sock, reply, data_size); - if (ret < 0) { - goto error_io; - } - - nb_event = be32toh(reply->nb_event); - tmp_events = zmalloc(sizeof(*tmp_events) * nb_event); - if (!tmp_events) { - ret = LTTNG_ERR_NOMEM; - goto error; - } - - for (i = 0; i < nb_event; i++) { - offset += len; - if (lttng_strncpy(tmp_events[i].name, reply->payload + offset, - sizeof(tmp_events[i].name))) { - ret = LTTNG_ERR_INVALID; - goto error; - } - tmp_events[i].pid = app->pid; - tmp_events[i].enabled = -1; - len = strlen(reply->payload + offset) + 1; - } - - *events = tmp_events; - - free(reply); - return nb_event; - -error_io: - ret = LTTNG_ERR_UST_LIST_FAIL; -error: - free(reply); - free(tmp_events); - return -ret; - -} - -/* - * Internal enable agent event on a agent application. This function - * communicates with the agent to enable a given event. - * - * Return LTTNG_OK on success or else a LTTNG_ERR* code. - */ -static int enable_event(const struct agent_app *app, struct agent_event *event) -{ - int ret; - char *bytes_to_send; - uint64_t data_size; - size_t filter_expression_length; - uint32_t reply_ret_code; - struct lttcomm_agent_enable_event msg; - struct lttcomm_agent_generic_reply reply; - - assert(app); - assert(app->sock); - assert(event); - - DBG2("Agent enabling event %s for app pid: %d and socket %d", event->name, - app->pid, app->sock->fd); - - /* - * Calculate the payload's size, which is the fixed-size struct followed - * by the variable-length filter expression (+1 for the ending \0). - */ - if (!event->filter_expression) { - filter_expression_length = 0; - } else { - filter_expression_length = strlen(event->filter_expression) + 1; - } - data_size = sizeof(msg) + filter_expression_length; - - memset(&msg, 0, sizeof(msg)); - msg.loglevel_value = htobe32(event->loglevel_value); - msg.loglevel_type = htobe32(event->loglevel_type); - if (lttng_strncpy(msg.name, event->name, sizeof(msg.name))) { - ret = LTTNG_ERR_INVALID; - goto error; - } - msg.filter_expression_length = htobe32(filter_expression_length); - - ret = send_header(app->sock, data_size, AGENT_CMD_ENABLE, 0); - if (ret < 0) { - goto error_io; - } - - bytes_to_send = zmalloc(data_size); - if (!bytes_to_send) { - ret = LTTNG_ERR_NOMEM; - goto error; - } - - memcpy(bytes_to_send, &msg, sizeof(msg)); - if (filter_expression_length > 0) { - memcpy(bytes_to_send + sizeof(msg), event->filter_expression, - filter_expression_length); - } - - ret = send_payload(app->sock, bytes_to_send, data_size); - free(bytes_to_send); - if (ret < 0) { - goto error_io; - } - - ret = recv_reply(app->sock, &reply, sizeof(reply)); - if (ret < 0) { - goto error_io; - } - - reply_ret_code = be32toh(reply.ret_code); - log_reply_code(reply_ret_code); - switch (reply_ret_code) { - case AGENT_RET_CODE_SUCCESS: - break; - case AGENT_RET_CODE_UNKNOWN_NAME: - ret = LTTNG_ERR_UST_EVENT_NOT_FOUND; - goto error; - default: - ret = LTTNG_ERR_UNK; - goto error; - } - - return LTTNG_OK; - -error_io: - ret = LTTNG_ERR_UST_ENABLE_FAIL; -error: - return ret; -} - -/* - * Send Pascal-style string. Size is sent as a 32-bit big endian integer. - */ -static -int send_pstring(struct lttcomm_sock *sock, const char *str, uint32_t len) -{ - int ret; - uint32_t len_be; - - len_be = htobe32(len); - ret = send_payload(sock, &len_be, sizeof(len_be)); - if (ret) { - goto end; - } - - ret = send_payload(sock, str, len); - if (ret) { - goto end; - } -end: - return ret; -} - -/* - * Internal enable application context on an agent application. This function - * communicates with the agent to enable a given application context. - * - * Return LTTNG_OK on success or else a LTTNG_ERR* code. - */ -static int app_context_op(const struct agent_app *app, - const struct agent_app_ctx *ctx, enum lttcomm_agent_command cmd) -{ - int ret; - uint32_t reply_ret_code; - struct lttcomm_agent_generic_reply reply; - size_t app_ctx_provider_name_len, app_ctx_name_len, data_size; - - assert(app); - assert(app->sock); - assert(ctx); - assert(cmd == AGENT_CMD_APP_CTX_ENABLE || - cmd == AGENT_CMD_APP_CTX_DISABLE); - - DBG2("Agent %s application %s:%s for app pid: %d and socket %d", - cmd == AGENT_CMD_APP_CTX_ENABLE ? "enabling" : "disabling", - ctx->provider_name, ctx->ctx_name, - app->pid, app->sock->fd); - - /* - * Calculate the payload's size, which consists of the size (u32, BE) - * of the provider name, the NULL-terminated provider name string, the - * size (u32, BE) of the context name, followed by the NULL-terminated - * context name string. - */ - app_ctx_provider_name_len = strlen(ctx->provider_name) + 1; - app_ctx_name_len = strlen(ctx->ctx_name) + 1; - data_size = sizeof(uint32_t) + app_ctx_provider_name_len + - sizeof(uint32_t) + app_ctx_name_len; - - ret = send_header(app->sock, data_size, cmd, 0); - if (ret < 0) { - goto error_io; - } - - if (app_ctx_provider_name_len > UINT32_MAX || - app_ctx_name_len > UINT32_MAX) { - ERR("Application context name > MAX_UINT32"); - ret = LTTNG_ERR_INVALID; - goto error; - } - - ret = send_pstring(app->sock, ctx->provider_name, - (uint32_t) app_ctx_provider_name_len); - if (ret < 0) { - goto error_io; - } - - ret = send_pstring(app->sock, ctx->ctx_name, - (uint32_t) app_ctx_name_len); - if (ret < 0) { - goto error_io; - } - - ret = recv_reply(app->sock, &reply, sizeof(reply)); - if (ret < 0) { - goto error_io; - } - - reply_ret_code = be32toh(reply.ret_code); - log_reply_code(reply_ret_code); - switch (reply_ret_code) { - case AGENT_RET_CODE_SUCCESS: - break; - default: - ret = LTTNG_ERR_UNK; - goto error; - } - - return LTTNG_OK; - -error_io: - ret = LTTNG_ERR_UST_ENABLE_FAIL; -error: - return ret; -} - -/* - * Internal disable agent event call on a agent application. This function - * communicates with the agent to disable a given event. - * - * Return LTTNG_OK on success or else a LTTNG_ERR* code. - */ -static int disable_event(struct agent_app *app, struct agent_event *event) -{ - int ret; - uint64_t data_size; - uint32_t reply_ret_code; - struct lttcomm_agent_disable_event msg; - struct lttcomm_agent_generic_reply reply; - - assert(app); - assert(app->sock); - assert(event); - - DBG2("Agent disabling event %s for app pid: %d and socket %d", event->name, - app->pid, app->sock->fd); - - data_size = sizeof(msg); - memset(&msg, 0, sizeof(msg)); - if (lttng_strncpy(msg.name, event->name, sizeof(msg.name))) { - ret = LTTNG_ERR_INVALID; - goto error; - } - - ret = send_header(app->sock, data_size, AGENT_CMD_DISABLE, 0); - if (ret < 0) { - goto error_io; - } - - ret = send_payload(app->sock, &msg, sizeof(msg)); - if (ret < 0) { - goto error_io; - } - - ret = recv_reply(app->sock, &reply, sizeof(reply)); - if (ret < 0) { - goto error_io; - } - - reply_ret_code = be32toh(reply.ret_code); - log_reply_code(reply_ret_code); - switch (reply_ret_code) { - case AGENT_RET_CODE_SUCCESS: - break; - case AGENT_RET_CODE_UNKNOWN_NAME: - ret = LTTNG_ERR_UST_EVENT_NOT_FOUND; - goto error; - default: - ret = LTTNG_ERR_UNK; - goto error; - } - - return LTTNG_OK; - -error_io: - ret = LTTNG_ERR_UST_DISABLE_FAIL; -error: - return ret; -} - -/* - * Send back the registration DONE command to a given agent application. - * - * Return 0 on success or else a negative value. - */ -int agent_send_registration_done(struct agent_app *app) -{ - assert(app); - assert(app->sock); - - DBG("Agent sending registration done to app socket %d", app->sock->fd); - - return send_header(app->sock, 0, AGENT_CMD_REG_DONE, 0); -} - -/* - * Enable agent event on every agent applications registered with the session - * daemon. - * - * Return LTTNG_OK on success or else a LTTNG_ERR* code. - */ -int agent_enable_event(struct agent_event *event, - enum lttng_domain_type domain) -{ - int ret; - struct agent_app *app; - struct lttng_ht_iter iter; - - assert(event); - - rcu_read_lock(); - - cds_lfht_for_each_entry(agent_apps_ht_by_sock->ht, &iter.iter, app, - node.node) { - if (app->domain != domain) { - continue; - } - - /* Enable event on agent application through TCP socket. */ - ret = enable_event(app, event); - if (ret != LTTNG_OK) { - goto error; - } - } - - event->enabled = 1; - ret = LTTNG_OK; - -error: - rcu_read_unlock(); - return ret; -} - -static -void destroy_app_ctx(struct agent_app_ctx *ctx) -{ - free(ctx->provider_name); - free(ctx->ctx_name); - free(ctx); -} - -static -struct agent_app_ctx *create_app_ctx(const struct lttng_event_context *ctx) -{ - struct agent_app_ctx *agent_ctx = NULL; - - if (!ctx) { - goto end; - } - - assert(ctx->ctx == LTTNG_EVENT_CONTEXT_APP_CONTEXT); - agent_ctx = zmalloc(sizeof(*ctx)); - if (!agent_ctx) { - goto end; - } - - agent_ctx->provider_name = strdup(ctx->u.app_ctx.provider_name); - agent_ctx->ctx_name = strdup(ctx->u.app_ctx.ctx_name); - if (!agent_ctx->provider_name || !agent_ctx->ctx_name) { - destroy_app_ctx(agent_ctx); - agent_ctx = NULL; - } -end: - return agent_ctx; -} - -/* - * Enable agent context on every agent applications registered with the session - * daemon. - * - * Return LTTNG_OK on success or else a LTTNG_ERR* code. - */ -int agent_enable_context(const struct lttng_event_context *ctx, - enum lttng_domain_type domain) -{ - int ret; - struct agent_app *app; - struct lttng_ht_iter iter; - - assert(ctx); - if (ctx->ctx != LTTNG_EVENT_CONTEXT_APP_CONTEXT) { - ret = LTTNG_ERR_INVALID; - goto error; - } - - rcu_read_lock(); - - cds_lfht_for_each_entry(agent_apps_ht_by_sock->ht, &iter.iter, app, - node.node) { - struct agent_app_ctx *agent_ctx; - - if (app->domain != domain) { - continue; - } - - agent_ctx = create_app_ctx(ctx); - if (!agent_ctx) { - ret = LTTNG_ERR_NOMEM; - goto error_unlock; - } - - /* Enable event on agent application through TCP socket. */ - ret = app_context_op(app, agent_ctx, AGENT_CMD_APP_CTX_ENABLE); - destroy_app_ctx(agent_ctx); - if (ret != LTTNG_OK) { - goto error_unlock; - } - } - - ret = LTTNG_OK; - -error_unlock: - rcu_read_unlock(); -error: - return ret; -} - -/* - * Disable agent event on every agent application registered with the session - * daemon. - * - * Return LTTNG_OK on success or else a LTTNG_ERR* code. - */ -int agent_disable_event(struct agent_event *event, - enum lttng_domain_type domain) -{ - int ret = LTTNG_OK; - struct agent_app *app; - struct lttng_ht_iter iter; - - assert(event); - if (!event->enabled) { - goto end; - } - - rcu_read_lock(); - - cds_lfht_for_each_entry(agent_apps_ht_by_sock->ht, &iter.iter, app, - node.node) { - if (app->domain != domain) { - continue; - } - - /* Enable event on agent application through TCP socket. */ - ret = disable_event(app, event); - if (ret != LTTNG_OK) { - goto error; - } - } - - event->enabled = 0; - -error: - rcu_read_unlock(); -end: - return ret; -} - -/* - * Disable agent context on every agent application registered with the session - * daemon. - * - * Return LTTNG_OK on success or else a LTTNG_ERR* code. - */ -static int disable_context(struct agent_app_ctx *ctx, - enum lttng_domain_type domain) -{ - int ret = LTTNG_OK; - struct agent_app *app; - struct lttng_ht_iter iter; - - assert(ctx); - - rcu_read_lock(); - DBG2("Disabling agent application context %s:%s", - ctx->provider_name, ctx->ctx_name); - cds_lfht_for_each_entry(agent_apps_ht_by_sock->ht, &iter.iter, app, - node.node) { - if (app->domain != domain) { - continue; - } - - ret = app_context_op(app, ctx, AGENT_CMD_APP_CTX_DISABLE); - if (ret != LTTNG_OK) { - goto end; - } - } -end: - rcu_read_unlock(); - return ret; -} - -/* - * Ask every agent for the list of possible event. Events is allocated with the - * events of every agent application. - * - * Return the number of events or else a negative value. - */ -int agent_list_events(struct lttng_event **events, - enum lttng_domain_type domain) -{ - int ret; - size_t nbmem, count = 0; - struct agent_app *app; - struct lttng_event *tmp_events = NULL; - struct lttng_ht_iter iter; - - assert(events); - - DBG2("Agent listing events for domain %d", domain); - - nbmem = UST_APP_EVENT_LIST_SIZE; - tmp_events = zmalloc(nbmem * sizeof(*tmp_events)); - if (!tmp_events) { - PERROR("zmalloc agent list events"); - ret = -ENOMEM; - goto error; - } - - rcu_read_lock(); - cds_lfht_for_each_entry(agent_apps_ht_by_sock->ht, &iter.iter, app, - node.node) { - ssize_t nb_ev; - struct lttng_event *agent_events; - - /* Skip domain not asked by the list. */ - if (app->domain != domain) { - continue; - } - - nb_ev = list_events(app, &agent_events); - if (nb_ev < 0) { - ret = nb_ev; - goto error_unlock; - } - - if (count + nb_ev > nbmem) { - /* In case the realloc fails, we free the memory */ - struct lttng_event *new_tmp_events; - size_t new_nbmem; - - new_nbmem = max_t(size_t, count + nb_ev, nbmem << 1); - DBG2("Reallocating agent event list from %zu to %zu entries", - nbmem, new_nbmem); - new_tmp_events = realloc(tmp_events, - new_nbmem * sizeof(*new_tmp_events)); - if (!new_tmp_events) { - PERROR("realloc agent events"); - ret = -ENOMEM; - free(agent_events); - goto error_unlock; - } - /* Zero the new memory */ - memset(new_tmp_events + nbmem, 0, - (new_nbmem - nbmem) * sizeof(*new_tmp_events)); - nbmem = new_nbmem; - tmp_events = new_tmp_events; - } - memcpy(tmp_events + count, agent_events, - nb_ev * sizeof(*tmp_events)); - free(agent_events); - count += nb_ev; - } - rcu_read_unlock(); - - ret = count; - *events = tmp_events; - return ret; - -error_unlock: - rcu_read_unlock(); -error: - free(tmp_events); - return ret; -} - -/* - * Create a agent app object using the given PID. - * - * Return newly allocated object or else NULL on error. - */ -struct agent_app *agent_create_app(pid_t pid, enum lttng_domain_type domain, - struct lttcomm_sock *sock) -{ - struct agent_app *app; - - assert(sock); - - app = zmalloc(sizeof(*app)); - if (!app) { - PERROR("Failed to allocate agent application instance"); - goto error; - } - - app->pid = pid; - app->domain = domain; - app->sock = sock; - lttng_ht_node_init_ulong(&app->node, (unsigned long) app->sock->fd); - -error: - return app; -} - -/* - * Lookup agent app by socket in the global hash table. - * - * RCU read side lock MUST be acquired. - * - * Return object if found else NULL. - */ -struct agent_app *agent_find_app_by_sock(int sock) -{ - struct lttng_ht_node_ulong *node; - struct lttng_ht_iter iter; - struct agent_app *app; - - assert(sock >= 0); - - lttng_ht_lookup(agent_apps_ht_by_sock, (void *)((unsigned long) sock), &iter); - node = lttng_ht_iter_get_node_ulong(&iter); - if (node == NULL) { - goto error; - } - app = caa_container_of(node, struct agent_app, node); - - DBG3("Agent app pid %d found by sock %d.", app->pid, sock); - return app; - -error: - DBG3("Agent app NOT found by sock %d.", sock); - return NULL; -} - -/* - * Add agent application object to the global hash table. - */ -void agent_add_app(struct agent_app *app) -{ - assert(app); - - DBG3("Agent adding app sock: %d and pid: %d to ht", app->sock->fd, app->pid); - lttng_ht_add_unique_ulong(agent_apps_ht_by_sock, &app->node); -} - -/* - * Delete agent application from the global hash table. - * - * rcu_read_lock() must be held by the caller. - */ -void agent_delete_app(struct agent_app *app) -{ - int ret; - struct lttng_ht_iter iter; - - assert(app); - - DBG3("Agent deleting app pid: %d and sock: %d", app->pid, app->sock->fd); - - iter.iter.node = &app->node.node; - ret = lttng_ht_del(agent_apps_ht_by_sock, &iter); - assert(!ret); -} - -/* - * Destroy an agent application object by detaching it from its corresponding - * UST app if one is connected by closing the socket. Finally, perform a - * delayed memory reclaim. - */ -void agent_destroy_app(struct agent_app *app) -{ - assert(app); - - if (app->sock) { - app->sock->ops->close(app->sock); - lttcomm_destroy_sock(app->sock); - } - - call_rcu(&app->node.head, destroy_app_agent_rcu); -} - -/* - * Initialize an already allocated agent object. - * - * Return 0 on success or else a negative errno value. - */ -int agent_init(struct agent *agt) -{ - int ret; - - assert(agt); - - agt->events = lttng_ht_new(0, LTTNG_HT_TYPE_STRING); - if (!agt->events) { - ret = -ENOMEM; - goto error; - } - lttng_ht_node_init_u64(&agt->node, agt->domain); - - CDS_INIT_LIST_HEAD(&agt->app_ctx_list); - return 0; - -error: - return ret; -} - -/* - * Add agent object to the given hash table. - */ -void agent_add(struct agent *agt, struct lttng_ht *ht) -{ - assert(agt); - assert(ht); - - DBG3("Agent adding from domain %d", agt->domain); - - lttng_ht_add_unique_u64(ht, &agt->node); -} - -/* - * Create an agent object for the given domain. - * - * Return the allocated agent or NULL on error. - */ -struct agent *agent_create(enum lttng_domain_type domain) -{ - int ret; - struct agent *agt; - - agt = zmalloc(sizeof(struct agent)); - if (!agt) { - goto error; - } - agt->domain = domain; - - ret = agent_init(agt); - if (ret < 0) { - free(agt); - agt = NULL; - goto error; - } - -error: - return agt; -} - -/* - * Create a newly allocated agent event data structure. - * Ownership of filter_expression is taken. - * - * Return a new object else NULL on error. - */ -struct agent_event *agent_create_event(const char *name, - enum lttng_loglevel_type loglevel_type, int loglevel_value, - struct lttng_filter_bytecode *filter, char *filter_expression) -{ - struct agent_event *event = NULL; - - DBG3("Agent create new event with name %s, loglevel type %d, \ - loglevel value %d and filter %s", - name, loglevel_type, loglevel_value, - filter_expression ? filter_expression : "NULL"); - - if (!name) { - ERR("Failed to create agent event; no name provided."); - goto error; - } - - event = zmalloc(sizeof(*event)); - if (!event) { - goto error; - } - - strncpy(event->name, name, sizeof(event->name)); - event->name[sizeof(event->name) - 1] = '\0'; - lttng_ht_node_init_str(&event->node, event->name); - - event->loglevel_value = loglevel_value; - event->loglevel_type = loglevel_type; - event->filter = filter; - event->filter_expression = filter_expression; -error: - return event; -} - -/* - * Unique add of a agent event to an agent object. - */ -void agent_add_event(struct agent_event *event, struct agent *agt) -{ - assert(event); - assert(agt); - assert(agt->events); - - DBG3("Agent adding event %s", event->name); - add_unique_agent_event(agt->events, event); - agt->being_used = 1; -} - -/* - * Unique add of a agent context to an agent object. - */ -int agent_add_context(const struct lttng_event_context *ctx, struct agent *agt) -{ - int ret = LTTNG_OK; - struct agent_app_ctx *agent_ctx = NULL; - - assert(ctx); - assert(agt); - assert(agt->events); - assert(ctx->ctx == LTTNG_EVENT_CONTEXT_APP_CONTEXT); - - agent_ctx = create_app_ctx(ctx); - if (!agent_ctx) { - ret = LTTNG_ERR_NOMEM; - goto end; - } - - DBG3("Agent adding context %s:%s", ctx->u.app_ctx.provider_name, - ctx->u.app_ctx.ctx_name); - cds_list_add_tail_rcu(&agent_ctx->list_node, &agt->app_ctx_list); -end: - return ret; -} - -/* - * Find multiple agent events sharing the given name. - * - * RCU read side lock MUST be acquired. It must be held for the - * duration of the iteration. - * - * Sets the given iterator. - */ -void agent_find_events_by_name(const char *name, struct agent *agt, - struct lttng_ht_iter* iter) -{ - struct lttng_ht *ht; - struct agent_ht_key key; - - assert(name); - assert(agt); - assert(agt->events); - assert(iter); - - ht = agt->events; - key.name = name; - - cds_lfht_lookup(ht->ht, ht->hash_fct((void *) name, lttng_ht_seed), - ht_match_event_by_name, &key, &iter->iter); -} - -/* - * Get the next agent event duplicate by name. This should be called - * after a call to agent_find_events_by_name() to iterate on events. - * - * The RCU read lock must be held during the iteration and for as long - * as the object the iterator points to remains in use. - */ -void agent_event_next_duplicate(const char *name, - struct agent *agt, struct lttng_ht_iter* iter) -{ - struct agent_ht_key key; - - key.name = name; - - cds_lfht_next_duplicate(agt->events->ht, ht_match_event_by_name, - &key, &iter->iter); -} - -/* - * Find a agent event in the given agent using name, loglevel and filter. - * - * RCU read side lock MUST be acquired. It must be kept for as long as - * the returned agent_event is used. - * - * Return object if found else NULL. - */ -struct agent_event *agent_find_event(const char *name, - enum lttng_loglevel_type loglevel_type, int loglevel_value, - char *filter_expression, struct agent *agt) -{ - struct lttng_ht_node_str *node; - struct lttng_ht_iter iter; - struct lttng_ht *ht; - struct agent_ht_key key; - - assert(name); - assert(agt); - assert(agt->events); - - ht = agt->events; - key.name = name; - key.loglevel_value = loglevel_value; - key.loglevel_type = loglevel_type; - key.filter_expression = filter_expression; - - cds_lfht_lookup(ht->ht, ht->hash_fct((void *) name, lttng_ht_seed), - ht_match_event, &key, &iter.iter); - node = lttng_ht_iter_get_node_str(&iter); - if (node == NULL) { - goto error; - } - - DBG3("Agent event found %s.", name); - return caa_container_of(node, struct agent_event, node); - -error: - DBG3("Agent event NOT found %s.", name); - return NULL; -} - -/* - * Free given agent event. This event must not be globally visible at this - * point (only expected to be used on failure just after event creation). After - * this call, the pointer is not usable anymore. - */ -void agent_destroy_event(struct agent_event *event) -{ - assert(event); - - free(event->filter); - free(event->filter_expression); - free(event->exclusion); - free(event); -} - -static -void destroy_app_ctx_rcu(struct rcu_head *head) -{ - struct agent_app_ctx *ctx = - caa_container_of(head, struct agent_app_ctx, rcu_node); - - destroy_app_ctx(ctx); -} - -/* - * Destroy an agent completely. - */ -void agent_destroy(struct agent *agt) -{ - struct lttng_ht_node_str *node; - struct lttng_ht_iter iter; - struct agent_app_ctx *ctx; - - assert(agt); - - DBG3("Agent destroy"); - - rcu_read_lock(); - cds_lfht_for_each_entry(agt->events->ht, &iter.iter, node, node) { - int ret; - struct agent_event *event; - - /* - * When destroying an event, we have to try to disable it on the - * agent side so the event stops generating data. The return - * value is not important since we have to continue anyway - * destroying the object. - */ - event = caa_container_of(node, struct agent_event, node); - (void) agent_disable_event(event, agt->domain); - - ret = lttng_ht_del(agt->events, &iter); - assert(!ret); - call_rcu(&node->head, destroy_event_agent_rcu); - } - - cds_list_for_each_entry_rcu(ctx, &agt->app_ctx_list, list_node) { - (void) disable_context(ctx, agt->domain); - cds_list_del(&ctx->list_node); - call_rcu(&ctx->rcu_node, destroy_app_ctx_rcu); - } - rcu_read_unlock(); - ht_cleanup_push(agt->events); - free(agt); -} - -/* - * Allocate agent_apps_ht_by_sock. - */ -int agent_app_ht_alloc(void) -{ - int ret = 0; - - agent_apps_ht_by_sock = lttng_ht_new(0, LTTNG_HT_TYPE_ULONG); - if (!agent_apps_ht_by_sock) { - ret = -1; - } - - return ret; -} - -/* - * Destroy a agent application by socket. - */ -void agent_destroy_app_by_sock(int sock) -{ - struct agent_app *app; - - assert(sock >= 0); - - /* - * Not finding an application is a very important error that should NEVER - * happen. The hash table deletion is ONLY done through this call when the - * main sessiond thread is torn down. - */ - rcu_read_lock(); - app = agent_find_app_by_sock(sock); - assert(app); - - /* RCU read side lock is assumed to be held by this function. */ - agent_delete_app(app); - - /* The application is freed in a RCU call but the socket is closed here. */ - agent_destroy_app(app); - rcu_read_unlock(); -} - -/* - * Clean-up the agent app hash table and destroy it. - */ -void agent_app_ht_clean(void) -{ - struct lttng_ht_node_ulong *node; - struct lttng_ht_iter iter; - - if (!agent_apps_ht_by_sock) { - return; - } - rcu_read_lock(); - cds_lfht_for_each_entry(agent_apps_ht_by_sock->ht, &iter.iter, node, node) { - struct agent_app *app; - - app = caa_container_of(node, struct agent_app, node); - agent_destroy_app_by_sock(app->sock->fd); - } - rcu_read_unlock(); - - lttng_ht_destroy(agent_apps_ht_by_sock); -} - -/* - * Update a agent application (given socket) using the given agent. - * - * Note that this function is most likely to be used with a tracing session - * thus the caller should make sure to hold the appropriate lock(s). - */ -void agent_update(const struct agent *agt, const struct agent_app *app) -{ - int ret; - struct agent_event *event; - struct lttng_ht_iter iter; - struct agent_app_ctx *ctx; - - assert(agt); - assert(app); - - DBG("Agent updating app: pid = %ld", (long) app->pid); - - rcu_read_lock(); - /* - * We are in the registration path thus if the application is gone, - * there is a serious code flow error. - */ - - cds_lfht_for_each_entry(agt->events->ht, &iter.iter, event, node.node) { - /* Skip event if disabled. */ - if (!event->enabled) { - continue; - } - - ret = enable_event(app, event); - if (ret != LTTNG_OK) { - DBG2("Agent update unable to enable event %s on app pid: %d sock %d", - event->name, app->pid, app->sock->fd); - /* Let's try the others here and don't assume the app is dead. */ - continue; - } - } - - cds_list_for_each_entry_rcu(ctx, &agt->app_ctx_list, list_node) { - ret = app_context_op(app, ctx, AGENT_CMD_APP_CTX_ENABLE); - if (ret != LTTNG_OK) { - DBG2("Agent update unable to add application context %s:%s on app pid: %d sock %d", - ctx->provider_name, ctx->ctx_name, - app->pid, app->sock->fd); - continue; - } - } - - rcu_read_unlock(); -}