From 0f342d4595475e8d45cd954f040a5e9dab0a277f Mon Sep 17 00:00:00 2001 From: Martin Schwenke Date: Mon, 27 Aug 2018 14:47:38 +1000 Subject: ctdb-daemon: Wait for eventd to be ready before connecting The current method of retrying the connection to eventd means that messages get logged for each failure. Instead, pass a pipe file descriptor to eventd and wait for it to write 0 to the pipe to indicate that it is ready to accept client connections. BUG: https://bugzilla.samba.org/show_bug.cgi?id=13592 Signed-off-by: Martin Schwenke Reviewed-by: Amitay Isaacs (cherry picked from commit 62ec1ab1470206d6a2cf300f30ca0b4a39413a38) Signed-off-by: Martin Schwenke --- ctdb/server/eventscript.c | 118 +++++++++++++++++++++++++++++++++++++++++++--- 1 file changed, 111 insertions(+), 7 deletions(-) diff --git a/ctdb/server/eventscript.c b/ctdb/server/eventscript.c index 02924a7f471..eb87067a14b 100644 --- a/ctdb/server/eventscript.c +++ b/ctdb/server/eventscript.c @@ -142,6 +142,100 @@ static bool eventd_context_init(TALLOC_CTX *mem_ctx, return true; } +struct eventd_startup_state { + bool done; + int ret; + int fd; +}; + +static void eventd_startup_timeout_handler(struct tevent_context *ev, + struct tevent_timer *te, + struct timeval t, + void *private_data) +{ + struct eventd_startup_state *state = + (struct eventd_startup_state *) private_data; + + state->done = true; + state->ret = ETIMEDOUT; +} + +static void eventd_startup_handler(struct tevent_context *ev, + struct tevent_fd *fde, uint16_t flags, + void *private_data) +{ + struct eventd_startup_state *state = + (struct eventd_startup_state *)private_data; + unsigned int data; + ssize_t num_read; + + num_read = sys_read(state->fd, &data, sizeof(data)); + if (num_read == sizeof(data)) { + if (data == 0) { + state->ret = 0; + } else { + state->ret = EIO; + } + } else if (num_read == 0) { + state->ret = EPIPE; + } else if (num_read == -1) { + state->ret = errno; + } else { + state->ret = EINVAL; + } + + state->done = true; +} + + +static int wait_for_daemon_startup(struct tevent_context *ev, + int fd) +{ + TALLOC_CTX *mem_ctx; + struct tevent_timer *timer; + struct tevent_fd *fde; + struct eventd_startup_state state = { + .done = false, + .ret = 0, + .fd = fd, + }; + + mem_ctx = talloc_new(ev); + if (mem_ctx == NULL) { + return ENOMEM; + } + + timer = tevent_add_timer(ev, + mem_ctx, + tevent_timeval_current_ofs(10, 0), + eventd_startup_timeout_handler, + &state); + if (timer == NULL) { + talloc_free(mem_ctx); + return ENOMEM; + } + + fde = tevent_add_fd(ev, + mem_ctx, + fd, + TEVENT_FD_READ, + eventd_startup_handler, + &state); + if (fde == NULL) { + talloc_free(mem_ctx); + return ENOMEM; + } + + while (! state.done) { + tevent_loop_once(ev); + } + + talloc_free(mem_ctx); + + return state.ret; +} + + /* * Start and stop event daemon */ @@ -180,7 +274,7 @@ int ctdb_start_eventd(struct ctdb_context *ctdb) return -1; } - argv = talloc_array(ectx, const char *, 14); + argv = talloc_array(ectx, const char *, 16); if (argv == NULL) { close(fd[0]); close(fd[1]); @@ -198,16 +292,18 @@ int ctdb_start_eventd(struct ctdb_context *ctdb) argv[8] = getenv("CTDB_LOGGING"); argv[9] = "-d"; argv[10] = debug_level_to_string(DEBUGLEVEL); + argv[11] = "-S"; + argv[12] = talloc_asprintf(argv, "%d", fd[1]); if (ectx->debug_hung_script == NULL) { - argv[11] = NULL; - argv[12] = NULL; + argv[13] = NULL; + argv[14] = NULL; } else { - argv[11] = "-D"; - argv[12] = ectx->debug_hung_script; + argv[13] = "-D"; + argv[14] = ectx->debug_hung_script; } - argv[13] = NULL; + argv[15] = NULL; - if (argv[6] == NULL) { + if (argv[6] == NULL || argv[12] == NULL) { close(fd[0]); close(fd[1]); talloc_free(argv); @@ -239,6 +335,14 @@ int ctdb_start_eventd(struct ctdb_context *ctdb) talloc_free(argv); close(fd[1]); + ret = wait_for_daemon_startup(ctdb->ev, fd[0]); + if (ret != 0) { + ctdb_kill(ctdb, pid, SIGKILL); + close(fd[0]); + D_ERR("Failed to initialize event daemon (%d)\n", ret); + return -1; + } + ectx->eventd_fde = tevent_add_fd(ctdb->ev, ectx, fd[0], TEVENT_FD_READ, eventd_dead_handler, ectx); -- cgit v1.2.1