X-Git-Url: http://git.lttng.org./?a=blobdiff_plain;f=libust%2Flttng-ust-comm.c;h=a38c5733075b24feab74880cd00697318ab8611e;hb=003fedf4968e55d8f7711faf784a37d2804c3a21;hp=a5f2b0b0069de494f0fb44dd14fdde78537002e6;hpb=80e2814bbd91e86984f24a74cc75f9cc4aaa6824;p=lttng-ust.git diff --git a/libust/lttng-ust-comm.c b/libust/lttng-ust-comm.c index a5f2b0b0..a38c5733 100644 --- a/libust/lttng-ust-comm.c +++ b/libust/lttng-ust-comm.c @@ -39,6 +39,7 @@ #include #include +#include #include #include #include @@ -119,6 +120,8 @@ struct sock_info local_apps = { .socket = -1, }; +static int wait_poll_fallback; + extern void ltt_ring_buffer_client_overwrite_init(void); extern void ltt_ring_buffer_client_discard_init(void); extern void ltt_ring_buffer_metadata_client_init(void); @@ -179,18 +182,18 @@ int register_app_to_sessiond(int socket) return -errno; } - ret = lttcomm_send_unix_sock(socket, ®_msg, sizeof(reg_msg)); + ret = ustcomm_send_unix_sock(socket, ®_msg, sizeof(reg_msg)); if (ret >= 0 && ret != sizeof(reg_msg)) return -EIO; return ret; } static -int send_reply(int sock, struct lttcomm_ust_reply *lur) +int send_reply(int sock, struct ustcomm_ust_reply *lur) { ssize_t len; - len = lttcomm_send_unix_sock(sock, lur, sizeof(*lur)); + len = ustcomm_send_unix_sock(sock, lur, sizeof(*lur)); switch (len) { case sizeof(*lur): DBG("message successfully sent"); @@ -215,6 +218,9 @@ int handle_register_done(struct sock_info *sock_info) if (sock_info->constructor_sem_posted) return 0; sock_info->constructor_sem_posted = 1; + if (uatomic_read(&sem_count) <= 0) { + return 0; + } ret = uatomic_add_return(&sem_count, -1); if (ret == 0) { ret = sem_post(&constructor_wait); @@ -225,11 +231,12 @@ int handle_register_done(struct sock_info *sock_info) static int handle_message(struct sock_info *sock_info, - int sock, struct lttcomm_ust_msg *lum) + int sock, struct ustcomm_ust_msg *lum) { int ret = 0; const struct objd_ops *ops; - struct lttcomm_ust_reply lur; + struct ustcomm_ust_reply lur; + int shm_fd, wait_fd; ust_lock(); @@ -273,12 +280,58 @@ end: lur.cmd = lum->cmd; lur.ret_val = ret; if (ret >= 0) { - lur.ret_code = LTTCOMM_OK; + lur.ret_code = USTCOMM_OK; } else { - lur.ret_code = LTTCOMM_SESSION_FAIL; + //lur.ret_code = USTCOMM_SESSION_FAIL; + lur.ret_code = ret; + } + switch (lum->cmd) { + case LTTNG_UST_STREAM: + /* + * Special-case reply to send stream info. + * Use lum.u output. + */ + lur.u.stream.memory_map_size = lum->u.stream.memory_map_size; + shm_fd = lum->u.stream.shm_fd; + wait_fd = lum->u.stream.wait_fd; + break; + case LTTNG_UST_METADATA: + case LTTNG_UST_CHANNEL: + lur.u.channel.memory_map_size = lum->u.channel.memory_map_size; + shm_fd = lum->u.channel.shm_fd; + wait_fd = lum->u.channel.wait_fd; + break; + case LTTNG_UST_VERSION: + lur.u.version = lum->u.version; + break; } ret = send_reply(sock, &lur); + if (ret < 0) { + perror("error sending reply"); + goto error; + } + if ((lum->cmd == LTTNG_UST_STREAM + || lum->cmd == LTTNG_UST_CHANNEL + || lum->cmd == LTTNG_UST_METADATA) + && lur.ret_code == USTCOMM_OK) { + /* we also need to send the file descriptors. */ + ret = ustcomm_send_fds_unix_sock(sock, + &shm_fd, &shm_fd, + 1, sizeof(int)); + if (ret < 0) { + perror("send shm_fd"); + goto error; + } + ret = ustcomm_send_fds_unix_sock(sock, + &wait_fd, &wait_fd, + 1, sizeof(int)); + if (ret < 0) { + perror("send wait_fd"); + goto error; + } + } +error: ust_unlock(); return ret; } @@ -485,6 +538,9 @@ void wait_for_sessiond(struct sock_info *sock_info) if (lttng_ust_comm_should_quit) { goto quit; } + if (wait_poll_fallback) { + goto error; + } if (!sock_info->wait_shm_mmap) { sock_info->wait_shm_mmap = get_map_shm(sock_info); if (!sock_info->wait_shm_mmap) @@ -497,13 +553,17 @@ void wait_for_sessiond(struct sock_info *sock_info) if (uatomic_read((int32_t *) sock_info->wait_shm_mmap) == 0) { ret = futex_async((int32_t *) sock_info->wait_shm_mmap, FUTEX_WAIT, 0, NULL, NULL, 0); - /* - * FIXME: Currently, futexes on read-only shm seems to - * EFAULT. - */ if (ret < 0) { + if (errno == EFAULT) { + wait_poll_fallback = 1; + WARN( +"Linux kernels 2.6.33 to 3.0 (with the exception of stable versions) " +"do not support FUTEX_WAKE on read-only memory mappings correctly. " +"Please upgrade your kernel " +"(fix is commit 9ea71503a8ed9184d2d0b8ccc4d269d05f7940ae in Linux kernel " +"mainline). LTTng-UST will use polling mode fallback."); + } PERROR("futex"); - sleep(5); } } return; @@ -514,8 +574,6 @@ quit: error: ust_unlock(); - /* Error handling: fallback on a 5 seconds sleep. */ - sleep(5); return; } @@ -530,10 +588,25 @@ static void *ust_listener_thread(void *arg) { struct sock_info *sock_info = arg; - int sock, ret; + int sock, ret, prev_connect_failed = 0, has_waited = 0; /* Restart trying to connect to the session daemon */ restart: + if (prev_connect_failed) { + /* Wait for sessiond availability with pipe */ + wait_for_sessiond(sock_info); + if (has_waited) { + has_waited = 0; + /* + * Sleep for 5 seconds before retrying after a + * sequence of failure / wait / failure. This + * deals with a killed or broken session daemon. + */ + sleep(5); + } + has_waited = 1; + prev_connect_failed = 0; + } ust_lock(); if (lttng_ust_comm_should_quit) { @@ -550,9 +623,10 @@ restart: } /* Register */ - ret = lttcomm_connect_unix_sock(sock_info->sock_path); + ret = ustcomm_connect_unix_sock(sock_info->sock_path); if (ret < 0) { ERR("Error connecting to %s apps socket", sock_info->name); + prev_connect_failed = 1; /* * If we cannot find the sessiond daemon, don't delay * constructor execution. @@ -560,9 +634,6 @@ restart: ret = handle_register_done(sock_info); assert(!ret); ust_unlock(); - - /* Wait for sessiond availability with pipe */ - wait_for_sessiond(sock_info); goto restart; } @@ -574,7 +645,7 @@ restart: */ if (sock_info->root_handle == -1) { ret = lttng_abi_create_root_handle(); - if (ret) { + if (ret < 0) { ERR("Error creating root handle"); ust_unlock(); goto quit; @@ -585,6 +656,7 @@ restart: ret = register_app_to_sessiond(sock); if (ret < 0) { ERR("Error registering to %s apps socket", sock_info->name); + prev_connect_failed = 1; /* * If we cannot register to the sessiond daemon, don't * delay constructor execution. @@ -592,16 +664,15 @@ restart: ret = handle_register_done(sock_info); assert(!ret); ust_unlock(); - wait_for_sessiond(sock_info); goto restart; } ust_unlock(); for (;;) { ssize_t len; - struct lttcomm_ust_msg lum; + struct ustcomm_ust_msg lum; - len = lttcomm_recv_unix_sock(sock, &lum, sizeof(lum)); + len = ustcomm_recv_unix_sock(sock, &lum, sizeof(lum)); switch (len) { case 0: /* orderly shutdown */ DBG("%s ltt-sessiond has performed an orderly shutdown\n", sock_info->name); @@ -748,7 +819,7 @@ void lttng_ust_cleanup(int exiting) cleanup_sock_info(&local_apps); } lttng_ust_abi_exit(); - ltt_events_exit(); + lttng_ust_events_exit(); ltt_ring_buffer_client_discard_exit(); ltt_ring_buffer_client_overwrite_exit(); ltt_ring_buffer_metadata_client_exit(); @@ -857,6 +928,7 @@ void ust_after_fork_child(ust_fork_info_t *fork_info) /* Release urcu mutexes */ rcu_bp_after_fork_child(); lttng_ust_cleanup(0); + lttng_context_vtid_reset(); /* Release mutexes and reenable signals */ ust_after_fork_common(fork_info); lttng_ust_init();