/* * Functions managing applets * * Copyright 2000-2015 Willy Tarreau * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation; either version * 2 of the License, or (at your option) any later version. * */ #include #include #include #include #include #include #include #include #include #include #include unsigned int nb_applets = 0; DECLARE_POOL(pool_head_appctx, "appctx", sizeof(struct appctx)); /* trace source and events */ static void applet_trace(enum trace_level level, uint64_t mask, const struct trace_source *src, const struct ist where, const struct ist func, const void *a1, const void *a2, const void *a3, const void *a4); /* The event representation is split like this : * app - applet */ static const struct trace_event applet_trace_events[] = { #define APPLET_EV_NEW (1ULL << 0) { .mask = APPLET_EV_NEW, .name = "app_new", .desc = "new appctx" }, #define APPLET_EV_FREE (1ULL << 1) { .mask = APPLET_EV_FREE, .name = "app_free", .desc = "free appctx" }, #define APPLET_EV_RELEASE (1ULL << 2) { .mask = APPLET_EV_RELEASE, .name = "app_release", .desc = "release appctx" }, #define APPLET_EV_PROCESS (1ULL << 3) { .mask = APPLET_EV_PROCESS, .name = "app_proc", .desc = "process appctx" }, #define APPLET_EV_ERR (1ULL << 4) { .mask = APPLET_EV_ERR, .name = "app_err", .desc = "error on appctx" }, #define APPLET_EV_START (1ULL << 5) { .mask = APPLET_EV_START, .name = "app_start", .desc = "start appctx" }, {} }; static const struct name_desc applet_trace_lockon_args[4] = { /* arg1 */ { /* already used by the applet */ }, /* arg2 */ { }, /* arg3 */ { }, /* arg4 */ { } }; static const struct name_desc applet_trace_decoding[] = { #define STRM_VERB_CLEAN 1 { .name="clean", .desc="only user-friendly stuff, generally suitable for level \"user\"" }, #define STRM_VERB_MINIMAL 2 { .name="minimal", .desc="report info on streams and connectors" }, #define STRM_VERB_SIMPLE 3 { .name="simple", .desc="add info on request and response channels" }, #define STRM_VERB_ADVANCED 4 { .name="advanced", .desc="add info on channel's buffer for data and developer levels only" }, #define STRM_VERB_COMPLETE 5 { .name="complete", .desc="add info on channel's buffer" }, { /* end */ } }; static struct trace_source trace_applet = { .name = IST("applet"), .desc = "Applet endpoint", .arg_def = TRC_ARG1_APPCTX, // TRACE()'s first argument is always an appctx .default_cb = applet_trace, .known_events = applet_trace_events, .lockon_args = applet_trace_lockon_args, .decoding = applet_trace_decoding, .report_events = ~0, // report everything by default }; #define TRACE_SOURCE &trace_applet INITCALL1(STG_REGISTER, trace_register_source, TRACE_SOURCE); /* the applet traces always expect that arg1, if non-null, is of a appctx (from * which we can derive everything). */ static void applet_trace(enum trace_level level, uint64_t mask, const struct trace_source *src, const struct ist where, const struct ist func, const void *a1, const void *a2, const void *a3, const void *a4) { const struct appctx *appctx = a1; const struct stconn *sc = NULL, *sco = NULL; const struct stream *s = NULL; const struct channel *ic = NULL, *oc = NULL; if (!appctx || src->verbosity < STRM_VERB_CLEAN) return; sc = appctx_sc(appctx); if (sc) { s = __sc_strm(sc); sco = sc_opposite(sc); ic = sc_ic(sc); oc = sc_oc(sc); } /* General info about the stream (htx/tcp, id...) */ if (s) chunk_appendf(&trace_buf, " : [%s,%s]", appctx->applet->name, ((s->flags & SF_HTX) ? "HTX" : "TCP")); else chunk_appendf(&trace_buf, " : [%s]", appctx->applet->name); if (sc) /* local and opposite stream connector state */ chunk_appendf(&trace_buf, " SC=(%s,%s)", sc_state_str(sc->state), sc_state_str(sco->state)); else /* local and opposite stream connector state */ chunk_appendf(&trace_buf, " SC=(none,none)"); if (src->verbosity == STRM_VERB_CLEAN) return; chunk_appendf(&trace_buf, " appctx=%p .t=%p .t.exp=%d .state=%d .st0=%d .st1=%d", appctx, appctx->t, tick_isset(appctx->t->expire) ? TICKS_TO_MS(appctx->t->expire - now_ms) : TICK_ETERNITY, appctx->state, appctx->st0, appctx->st1); if (!sc || src->verbosity == STRM_VERB_MINIMAL) return; chunk_appendf(&trace_buf, " - s=(%p,0x%08x,0x%x)", s, s->flags, s->conn_err_type); chunk_appendf(&trace_buf, " sc=(%p,%d,0x%08x,0x%x) sco=(%p,%d,0x%08x,0x%x) sc.exp(r,w)=(%d,%d) sco.exp(r,w)=(%d,%d)", sc, sc->state, sc->flags, sc->sedesc->flags, sco, sco->state, sco->flags, sco->sedesc->flags, tick_isset(sc_ep_rcv_ex(sc)) ? TICKS_TO_MS(sc_ep_rcv_ex(sc) - now_ms) : TICK_ETERNITY, tick_isset(sc_ep_snd_ex(sc)) ? TICKS_TO_MS(sc_ep_snd_ex(sc) - now_ms) : TICK_ETERNITY, tick_isset(sc_ep_rcv_ex(sco)) ? TICKS_TO_MS(sc_ep_rcv_ex(sco) - now_ms) : TICK_ETERNITY, tick_isset(sc_ep_snd_ex(sco)) ? TICKS_TO_MS(sc_ep_snd_ex(sco) - now_ms) : TICK_ETERNITY); /* If txn defined, don't display all channel info */ if (src->verbosity == STRM_VERB_SIMPLE) { chunk_appendf(&trace_buf, " ic=(%p .fl=0x%08x .exp=%d)", ic, ic->flags, tick_isset(ic->analyse_exp) ? TICKS_TO_MS(ic->analyse_exp - now_ms) : TICK_ETERNITY); chunk_appendf(&trace_buf, " oc=(%p .fl=0x%08x .exp=%d)", oc, oc->flags, tick_isset(oc->analyse_exp) ? TICKS_TO_MS(oc->analyse_exp - now_ms) : TICK_ETERNITY); } else { chunk_appendf(&trace_buf, " ic=(%p .fl=0x%08x .ana=0x%08x .exp=%u .o=%lu .tot=%llu .to_fwd=%u)", ic, ic->flags, ic->analysers, ic->analyse_exp, (long)ic->output, ic->total, ic->to_forward); chunk_appendf(&trace_buf, " oc=(%p .fl=0x%08x .ana=0x%08x .exp=%u .o=%lu .tot=%llu .to_fwd=%u)", oc, oc->flags, oc->analysers, oc->analyse_exp, (long)oc->output, oc->total, oc->to_forward); } if (src->verbosity == STRM_VERB_SIMPLE || (src->verbosity == STRM_VERB_ADVANCED && src->level < TRACE_LEVEL_DATA)) return; /* channels' buffer info */ if (s->flags & SF_HTX) { struct htx *ichtx = htxbuf(&ic->buf); struct htx *ochtx = htxbuf(&oc->buf); chunk_appendf(&trace_buf, " htx=(%u/%u#%u, %u/%u#%u)", ichtx->data, ichtx->size, htx_nbblks(ichtx), ochtx->data, ochtx->size, htx_nbblks(ochtx)); } else { chunk_appendf(&trace_buf, " buf=(%u@%p+%u/%u, %u@%p+%u/%u)", (unsigned int)b_data(&ic->buf), b_orig(&ic->buf), (unsigned int)b_head_ofs(&ic->buf), (unsigned int)b_size(&ic->buf), (unsigned int)b_data(&oc->buf), b_orig(&oc->buf), (unsigned int)b_head_ofs(&oc->buf), (unsigned int)b_size(&oc->buf)); } } /* Tries to allocate a new appctx and initialize all of its fields. The appctx * is returned on success, NULL on failure. The appctx must be released using * appctx_free(). is assigned as the applet, but it can be NULL. * is the thread ID to start the applet on, and a negative value allows the * applet to start anywhere. Backend applets may only be created on the current * thread. */ struct appctx *appctx_new_on(struct applet *applet, struct sedesc *sedesc, int thr) { struct appctx *appctx; /* Backend appctx cannot be started on another thread than the local one */ BUG_ON(thr != tid && sedesc); TRACE_ENTER(APPLET_EV_NEW); appctx = pool_zalloc(pool_head_appctx); if (unlikely(!appctx)) { TRACE_ERROR("APPCTX allocation failure", APPLET_EV_NEW|APPLET_EV_ERR); goto fail_appctx; } LIST_INIT(&appctx->wait_entry); appctx->obj_type = OBJ_TYPE_APPCTX; appctx->applet = applet; appctx->sess = NULL; appctx->t = task_new_on(thr); if (unlikely(!appctx->t)) { TRACE_ERROR("APPCTX task allocation failure", APPLET_EV_NEW|APPLET_EV_ERR); goto fail_task; } if (!sedesc) { sedesc = sedesc_new(); if (unlikely(!sedesc)) { TRACE_ERROR("APPCTX sedesc allocation failure", APPLET_EV_NEW|APPLET_EV_ERR); goto fail_endp; } sedesc->se = appctx; se_fl_set(sedesc, SE_FL_T_APPLET | SE_FL_ORPHAN); } appctx->sedesc = sedesc; appctx->t->process = task_run_applet; appctx->t->context = appctx; LIST_INIT(&appctx->buffer_wait.list); appctx->buffer_wait.target = appctx; appctx->buffer_wait.wakeup_cb = appctx_buf_available; _HA_ATOMIC_INC(&nb_applets); TRACE_LEAVE(APPLET_EV_NEW, appctx); return appctx; fail_endp: task_destroy(appctx->t); fail_task: pool_free(pool_head_appctx, appctx); fail_appctx: return NULL; } /* Finalize the frontend appctx startup. It must not be called for a backend * appctx. This function is responsible to create the appctx's session and the * frontend stream connector. By transitivity, the stream is also created. * * It returns 0 on success and -1 on error. In this case, it is the caller * responsibility to release the appctx. However, the session is released if it * was created. On success, if an error is encountered in the caller function, * the stream must be released instead of the appctx. To be sure, * appctx_free_on_early_error() must be called in this case. */ int appctx_finalize_startup(struct appctx *appctx, struct proxy *px, struct buffer *input) { struct session *sess; /* async startup is only possible for frontend appctx. Thus for orphan * appctx. Because no backend appctx can be orphan. */ BUG_ON(!se_fl_test(appctx->sedesc, SE_FL_ORPHAN)); TRACE_ENTER(APPLET_EV_START, appctx); sess = session_new(px, NULL, &appctx->obj_type); if (!sess) { TRACE_ERROR("APPCTX session allocation failure", APPLET_EV_START|APPLET_EV_ERR, appctx); return -1; } if (!sc_new_from_endp(appctx->sedesc, sess, input)) { session_free(sess); TRACE_ERROR("APPCTX sc allocation failure", APPLET_EV_START|APPLET_EV_ERR, appctx); return -1; } appctx->sess = sess; TRACE_LEAVE(APPLET_EV_START, appctx); return 0; } /* Release function to call when an error occurred during init stage of a * frontend appctx. For a backend appctx, it just calls appctx_free() */ void appctx_free_on_early_error(struct appctx *appctx) { /* If a frontend appctx is attached to a stream connector, release the stream * instead of the appctx. */ if (!se_fl_test(appctx->sedesc, SE_FL_ORPHAN) && !(appctx_sc(appctx)->flags & SC_FL_ISBACK)) { stream_free(appctx_strm(appctx)); return; } __appctx_free(appctx); } void appctx_free(struct appctx *appctx) { /* The task is supposed to be run on this thread, so we can just * check if it's running already (or about to run) or not */ if (!(appctx->t->state & (TASK_QUEUED | TASK_RUNNING))) { TRACE_POINT(APPLET_EV_FREE, appctx); __appctx_free(appctx); } else { /* if it's running, or about to run, defer the freeing * until the callback is called. */ appctx->state |= APPLET_WANT_DIE; task_wakeup(appctx->t, TASK_WOKEN_OTHER); TRACE_DEVEL("Cannot release APPCTX now, wake it up", APPLET_EV_FREE, appctx); } } /* reserves a command context of at least bytes in the , for * use by a CLI command or any regular applet. The pointer to this context is * stored in ctx.svcctx and is returned. The caller doesn't need to release * it as it's allocated from reserved space. If the size is larger than * APPLET_MAX_SVCCTX a crash will occur (hence that will never happen outside * of development). * * Note that the command does *not* initialize the area, so that it can easily * be used upon each entry in a function. It's left to the initialization code * to do it if needed. The CLI will always zero the whole area before calling * a keyword's ->parse() function. */ void *applet_reserve_svcctx(struct appctx *appctx, size_t size) { BUG_ON(size > APPLET_MAX_SVCCTX); appctx->svcctx = &appctx->svc.storage; return appctx->svcctx; } /* This is used to reset an svcctx and the svc.storage without releasing the * appctx. In fact this is only used by the CLI applet between commands. */ void applet_reset_svcctx(struct appctx *appctx) { memset(&appctx->svc.storage, 0, APPLET_MAX_SVCCTX); appctx->svcctx = NULL; } /* call the applet's release() function if any, and marks the sedesc as shut. * Needs to be called upon close(). */ void appctx_shut(struct appctx *appctx) { if (se_fl_test(appctx->sedesc, SE_FL_SHR | SE_FL_SHW)) return; TRACE_ENTER(APPLET_EV_RELEASE, appctx); if (appctx->applet->release) appctx->applet->release(appctx); if (LIST_INLIST(&appctx->buffer_wait.list)) LIST_DEL_INIT(&appctx->buffer_wait.list); se_fl_set(appctx->sedesc, SE_FL_SHRR | SE_FL_SHWN); TRACE_LEAVE(APPLET_EV_RELEASE, appctx); } /* Callback used to wake up an applet when a buffer is available. The applet * is woken up if an input buffer was requested for the associated * stream connector. In this case the buffer is immediately allocated and the * function returns 1. Otherwise it returns 0. Note that this automatically * covers multiple wake-up attempts by ensuring that the same buffer will not * be accounted for multiple times. */ int appctx_buf_available(void *arg) { struct appctx *appctx = arg; struct stconn *sc = appctx_sc(appctx); /* allocation requested ? */ if (!(sc->flags & SC_FL_NEED_BUFF)) return 0; sc_have_buff(sc); /* was already allocated another way ? if so, don't take this one */ if (c_size(sc_ic(sc)) || sc_ep_have_ff_data(sc_opposite(sc))) return 0; /* allocation possible now ? */ if (!b_alloc(&sc_ic(sc)->buf)) { sc_need_buff(sc); return 0; } task_wakeup(appctx->t, TASK_WOKEN_RES); return 1; } /* Default applet handler */ struct task *task_run_applet(struct task *t, void *context, unsigned int state) { struct appctx *app = context; struct stconn *sc, *sco; unsigned int rate; size_t count; int did_send = 0; TRACE_ENTER(APPLET_EV_PROCESS, app); if (app->state & APPLET_WANT_DIE) { TRACE_DEVEL("APPCTX want die, release it", APPLET_EV_FREE, app); __appctx_free(app); return NULL; } if (se_fl_test(app->sedesc, SE_FL_ORPHAN)) { /* Finalize init of orphan appctx. .init callback function must * be defined and it must finalize appctx startup. */ BUG_ON(!app->applet->init); if (appctx_init(app) == -1) { TRACE_DEVEL("APPCTX init failed", APPLET_EV_FREE|APPLET_EV_ERR, app); appctx_free_on_early_error(app); return NULL; } BUG_ON(!app->sess || !appctx_sc(app) || !appctx_strm(app)); TRACE_DEVEL("APPCTX initialized", APPLET_EV_PROCESS, app); } sc = appctx_sc(app); sco = sc_opposite(sc); /* We always pretend the applet can't get and doesn't want to * put, it's up to it to change this if needed. This ensures * that one applet which ignores any event will not spin. */ applet_need_more_data(app); applet_have_no_more_data(app); /* Now we'll try to allocate the input buffer. We wake up the applet in * all cases. So this is the applet's responsibility to check if this * buffer was allocated or not. This leaves a chance for applets to do * some other processing if needed. The applet doesn't have anything to * do if it needs the buffer, it will be called again upon readiness. */ if (!sc_alloc_ibuf(sc, &app->buffer_wait)) applet_have_more_data(app); count = co_data(sc_oc(sc)); app->applet->fct(app); TRACE_POINT(APPLET_EV_PROCESS, app); /* now check if the applet has released some room and forgot to * notify the other side about it. */ if (count != co_data(sc_oc(sc))) { sc_oc(sc)->flags |= CF_WRITE_EVENT | CF_WROTE_DATA; if (sco->room_needed < 0 || channel_recv_max(sc_oc(sc)) >= sco->room_needed) sc_have_room(sco); did_send = 1; } else { if (!sco->room_needed) sc_have_room(sco); } if (sc_ic(sc)->flags & CF_READ_EVENT) sc_ep_report_read_activity(sc); if (sc_waiting_room(sc) && (sc->flags & SC_FL_ABRT_DONE)) { sc_ep_set(sc, SE_FL_EOS|SE_FL_ERROR); } if (!co_data(sc_oc(sc))) { if (did_send) sc_ep_report_send_activity(sc); } else sc_ep_report_blocked_send(sc, did_send); /* measure the call rate and check for anomalies when too high */ if (((b_size(sc_ib(sc)) && sc->flags & SC_FL_NEED_BUFF) || // asks for a buffer which is present (b_size(sc_ib(sc)) && !b_data(sc_ib(sc)) && sc->flags & SC_FL_NEED_ROOM) || // asks for room in an empty buffer (b_data(sc_ob(sc)) && sc_is_send_allowed(sc)) || // asks for data already present (!b_data(sc_ib(sc)) && b_data(sc_ob(sc)) && // didn't return anything ... (!(sc_oc(sc)->flags & CF_WRITE_EVENT) && (sc->flags & SC_FL_SHUT_WANTED))))) { // ... and left data pending after a shut rate = update_freq_ctr(&app->call_rate, 1); if (rate >= 100000 && app->call_rate.prev_ctr) // looped like this more than 100k times over last second stream_dump_and_crash(&app->obj_type, read_freq_ctr(&app->call_rate)); } sc->app_ops->wake(sc); channel_release_buffer(sc_ic(sc), &app->buffer_wait); TRACE_LEAVE(APPLET_EV_PROCESS, app); return t; }