root/lib/pacemaker/pcmk_sched_probes.c

/* */

DEFINITIONS

1. add_expected_result
2. pcmk__probe_resource_list
3. probe_then_start
4. guest_resource_will_stop
5. probe_action
6. pcmk__probe_rsc_on_node
7. probe_needed_before_action
8. add_probe_orderings_for_stops
9. add_start_orderings_for_probe
10. add_restart_orderings_for_probe
11. clear_actions_tracking_flag
12. add_start_restart_orderings_for_rsc
13. order_then_probes
14. pcmk__order_probes
15. pcmk__schedule_probes

   1 /*
   2  * Copyright 2004-2023 the Pacemaker project contributors
   3  *
   4  * The version control history for this file may have further details.
   5  *
   6  * This source code is licensed under the GNU General Public License version 2
   7  * or later (GPLv2+) WITHOUT ANY WARRANTY.
   8  */
   9 
  10 #include <crm_internal.h>
  11 
  12 #include <glib.h>
  13 
  14 #include <crm/crm.h>
  15 #include <crm/pengine/status.h>
  16 #include <pacemaker-internal.h>
  17 #include "libpacemaker_private.h"
  18 
  19 /*!
  20  * \internal
  21  * \brief Add the expected result to a newly created probe
  22  *
  23  * \param[in,out] probe  Probe action to add expected result to
  24  * \param[in]     rsc    Resource that probe is for
  25  * \param[in]     node   Node that probe will run on
  26  */
  27 static void
  28 add_expected_result(pcmk_action_t *probe, const pcmk_resource_t *rsc,
     /*  */
  29                     const pcmk_node_t *node)
  30 {
  31     // Check whether resource is currently active on node
  32     pcmk_node_t *running = pe_find_node_id(rsc->running_on, node->details->id);
  33 
  34     // The expected result is what we think the resource's current state is
  35     if (running == NULL) {
  36         pe__add_action_expected_result(probe, CRM_EX_NOT_RUNNING);
  37 
  38     } else if (rsc->role == pcmk_role_promoted) {
  39         pe__add_action_expected_result(probe, CRM_EX_PROMOTED);
  40     }
  41 }
  42 
  43 /*!
  44  * \internal
  45  * \brief Create any needed robes on a node for a list of resources
  46  *
  47  * \param[in,out] rscs  List of resources to create probes for
  48  * \param[in,out] node  Node to create probes on
  49  *
  50  * \return true if any probe was created, otherwise false
  51  */
  52 bool
  53 pcmk__probe_resource_list(GList *rscs, pcmk_node_t *node)
     /*  */
  54 {
  55     bool any_created = false;
  56 
  57     for (GList *iter = rscs; iter != NULL; iter = iter->next) {
  58         pcmk_resource_t *rsc = (pcmk_resource_t *) iter->data;
  59 
  60         if (rsc->cmds->create_probe(rsc, node)) {
  61             any_created = true;
  62         }
  63     }
  64     return any_created;
  65 }
  66 
  67 /*!
  68  * \internal
  69  * \brief Order one resource's start after another's start-up probe
  70  *
  71  * \param[in,out] rsc1  Resource that might get start-up probe
  72  * \param[in]     rsc2  Resource that might be started
  73  */
  74 static void
  75 probe_then_start(pcmk_resource_t *rsc1, pcmk_resource_t *rsc2)
     /*  */
  76 {
  77     if ((rsc1->allocated_to != NULL)
  78         && (g_hash_table_lookup(rsc1->known_on,
  79                                 rsc1->allocated_to->details->id) == NULL)) {
  80 
  81         pcmk__new_ordering(rsc1,
  82                            pcmk__op_key(rsc1->id, PCMK_ACTION_MONITOR, 0),
  83                            NULL,
  84                            rsc2, pcmk__op_key(rsc2->id, PCMK_ACTION_START, 0),
  85                            NULL,
  86                            pcmk__ar_ordered, rsc1->cluster);
  87     }
  88 }
  89 
  90 /*!
  91  * \internal
  92  * \brief Check whether a guest resource will stop
  93  *
  94  * \param[in] node  Guest node to check
  95  *
  96  * \return true if guest resource will likely stop, otherwise false
  97  */
  98 static bool
  99 guest_resource_will_stop(const pcmk_node_t *node)
     /*  */
 100 {
 101     const pcmk_resource_t *guest_rsc = node->details->remote_rsc->container;
 102 
 103     /* Ideally, we'd check whether the guest has a required stop, but that
 104      * information doesn't exist yet, so approximate it ...
 105      */
 106     return node->details->remote_requires_reset
 107            || node->details->unclean
 108            || pcmk_is_set(guest_rsc->flags, pcmk_rsc_failed)
 109            || (guest_rsc->next_role == pcmk_role_stopped)
 110 
 111            // Guest is moving
 112            || ((guest_rsc->role > pcmk_role_stopped)
 113                && (guest_rsc->allocated_to != NULL)
 114                && (pe_find_node(guest_rsc->running_on,
 115                    guest_rsc->allocated_to->details->uname) == NULL));
 116 }
 117 
 118 /*!
 119  * \internal
 120  * \brief Create a probe action for a resource on a node
 121  *
 122  * \param[in,out] rsc   Resource to create probe for
 123  * \param[in,out] node  Node to create probe on
 124  *
 125  * \return Newly created probe action
 126  */
 127 static pcmk_action_t *
 128 probe_action(pcmk_resource_t *rsc, pcmk_node_t *node)
     /*  */
 129 {
 130     pcmk_action_t *probe = NULL;
 131     char *key = pcmk__op_key(rsc->id, PCMK_ACTION_MONITOR, 0);
 132 
 133     crm_debug("Scheduling probe of %s %s on %s",
 134               role2text(rsc->role), rsc->id, pe__node_name(node));
 135 
 136     probe = custom_action(rsc, key, PCMK_ACTION_MONITOR, node, FALSE,
 137                           rsc->cluster);
 138     pe__clear_action_flags(probe, pcmk_action_optional);
 139 
 140     pcmk__order_vs_unfence(rsc, node, probe, pcmk__ar_ordered);
 141     add_expected_result(probe, rsc, node);
 142     return probe;
 143 }
 144 
 145 /*!
 146  * \internal
 147  * \brief Create probes for a resource on a node, if needed
 148  *
 149  * \brief Schedule any probes needed for a resource on a node
 150  *
 151  * \param[in,out] rsc   Resource to create probe for
 152  * \param[in,out] node  Node to create probe on
 153  *
 154  * \return true if any probe was created, otherwise false
 155  */
 156 bool
 157 pcmk__probe_rsc_on_node(pcmk_resource_t *rsc, pcmk_node_t *node)
     /*  */
 158 {
 159     uint32_t flags = pcmk__ar_ordered;
 160     pcmk_action_t *probe = NULL;
 161     pcmk_node_t *allowed = NULL;
 162     pcmk_resource_t *top = uber_parent(rsc);
 163     const char *reason = NULL;
 164 
 165     CRM_ASSERT((rsc != NULL) && (node != NULL));
 166 
 167     if (!pcmk_is_set(rsc->cluster->flags, pcmk_sched_probe_resources)) {
 168         reason = "start-up probes are disabled";
 169         goto no_probe;
 170     }
 171 
 172     if (pe__is_guest_or_remote_node(node)) {
 173         const char *class = crm_element_value(rsc->xml, XML_AGENT_ATTR_CLASS);
 174 
 175         if (pcmk__str_eq(class, PCMK_RESOURCE_CLASS_STONITH, pcmk__str_none)) {
 176             reason = "Pacemaker Remote nodes cannot run stonith agents";
 177             goto no_probe;
 178 
 179         } else if (pe__is_guest_node(node)
 180                    && pe__resource_contains_guest_node(rsc->cluster, rsc)) {
 181             reason = "guest nodes cannot run resources containing guest nodes";
 182             goto no_probe;
 183 
 184         } else if (rsc->is_remote_node) {
 185             reason = "Pacemaker Remote nodes cannot host remote connections";
 186             goto no_probe;
 187         }
 188     }
 189 
 190     // If this is a collective resource, probes are created for its children
 191     if (rsc->children != NULL) {
 192         return pcmk__probe_resource_list(rsc->children, node);
 193     }
 194 
 195     if ((rsc->container != NULL) && !rsc->is_remote_node) {
 196         reason = "resource is inside a container";
 197         goto no_probe;
 198 
 199     } else if (pcmk_is_set(rsc->flags, pcmk_rsc_removed)) {
 200         reason = "resource is orphaned";
 201         goto no_probe;
 202 
 203     } else if (g_hash_table_lookup(rsc->known_on, node->details->id) != NULL) {
 204         reason = "resource state is already known";
 205         goto no_probe;
 206     }
 207 
 208     allowed = g_hash_table_lookup(rsc->allowed_nodes, node->details->id);
 209 
 210     if (rsc->exclusive_discover || top->exclusive_discover) {
 211         // Exclusive discovery is enabled ...
 212 
 213         if (allowed == NULL) {
 214             // ... but this node is not allowed to run the resource
 215             reason = "resource has exclusive discovery but is not allowed "
 216                      "on node";
 217             goto no_probe;
 218 
 219         } else if (allowed->rsc_discover_mode != pcmk_probe_exclusive) {
 220             // ... but no constraint marks this node for discovery of resource
 221             reason = "resource has exclusive discovery but is not enabled "
 222                      "on node";
 223             goto no_probe;
 224         }
 225     }
 226 
 227     if (allowed == NULL) {
 228         allowed = node;
 229     }
 230     if (allowed->rsc_discover_mode == pcmk_probe_never) {
 231         reason = "node has discovery disabled";
 232         goto no_probe;
 233     }
 234 
 235     if (pe__is_guest_node(node)) {
 236         pcmk_resource_t *guest = node->details->remote_rsc->container;
 237 
 238         if (guest->role == pcmk_role_stopped) {
 239             // The guest is stopped, so we know no resource is active there
 240             reason = "node's guest is stopped";
 241             probe_then_start(guest, top);
 242             goto no_probe;
 243 
 244         } else if (guest_resource_will_stop(node)) {
 245             reason = "node's guest will stop";
 246 
 247             // Order resource start after guest stop (in case it's restarting)
 248             pcmk__new_ordering(guest,
 249                                pcmk__op_key(guest->id, PCMK_ACTION_STOP, 0),
 250                                NULL, top,
 251                                pcmk__op_key(top->id, PCMK_ACTION_START, 0),
 252                                NULL, pcmk__ar_ordered, rsc->cluster);
 253             goto no_probe;
 254         }
 255     }
 256 
 257     // We've eliminated all cases where a probe is not needed, so now it is
 258     probe = probe_action(rsc, node);
 259 
 260     /* Below, we will order the probe relative to start or reload. If this is a
 261      * clone instance, the start or reload is for the entire clone rather than
 262      * just the instance. Otherwise, the start or reload is for the resource
 263      * itself.
 264      */
 265     if (!pe_rsc_is_clone(top)) {
 266         top = rsc;
 267     }
 268 
 269     /* Prevent a start if the resource can't be probed, but don't cause the
 270      * resource or entire clone to stop if already active.
 271      */
 272     if (!pcmk_is_set(probe->flags, pcmk_action_runnable)
 273         && (top->running_on == NULL)) {
 274         pe__set_order_flags(flags, pcmk__ar_unrunnable_first_blocks);
 275     }
 276 
 277     // Start or reload after probing the resource
 278     pcmk__new_ordering(rsc, NULL, probe,
 279                        top, pcmk__op_key(top->id, PCMK_ACTION_START, 0), NULL,
 280                        flags, rsc->cluster);
 281     pcmk__new_ordering(rsc, NULL, probe, top, reload_key(rsc), NULL,
 282                        pcmk__ar_ordered, rsc->cluster);
 283 
 284     return true;
 285 
 286 no_probe:
 287     pe_rsc_trace(rsc,
 288                  "Skipping probe for %s on %s because %s",
 289                  rsc->id, node->details->id, reason);
 290     return false;
 291 }
 292 
 293 /*!
 294  * \internal
 295  * \brief Check whether a probe should be ordered before another action
 296  *
 297  * \param[in] probe  Probe action to check
 298  * \param[in] then   Other action to check
 299  *
 300  * \return true if \p probe should be ordered before \p then, otherwise false
 301  */
 302 static bool
 303 probe_needed_before_action(const pcmk_action_t *probe,
     /*  */
 304                            const pcmk_action_t *then)
 305 {
 306     // Probes on a node are performed after unfencing it, not before
 307     if (pcmk__str_eq(then->task, PCMK_ACTION_STONITH, pcmk__str_none)
 308         && pe__same_node(probe->node, then->node)) {
 309         const char *op = g_hash_table_lookup(then->meta, "stonith_action");
 310 
 311         if (pcmk__str_eq(op, PCMK_ACTION_ON, pcmk__str_casei)) {
 312             return false;
 313         }
 314     }
 315 
 316     // Probes should be done on a node before shutting it down
 317     if (pcmk__str_eq(then->task, PCMK_ACTION_DO_SHUTDOWN, pcmk__str_none)
 318         && (probe->node != NULL) && (then->node != NULL)
 319         && !pe__same_node(probe->node, then->node)) {
 320         return false;
 321     }
 322 
 323     // Otherwise probes should always be done before any other action
 324     return true;
 325 }
 326 
 327 /*!
 328  * \internal
 329  * \brief Add implicit "probe then X" orderings for "stop then X" orderings
 330  *
 331  * If the state of a resource is not known yet, a probe will be scheduled,
 332  * expecting a "not running" result. If the probe fails, a stop will not be
 333  * scheduled until the next transition. Thus, if there are ordering constraints
 334  * like "stop this resource then do something else that's not for the same
 335  * resource", add implicit "probe this resource then do something" equivalents
 336  * so the relation is upheld until we know whether a stop is needed.
 337  *
 338  * \param[in,out] scheduler  Scheduler data
 339  */
 340 static void
 341 add_probe_orderings_for_stops(pcmk_scheduler_t *scheduler)
     /*  */
 342 {
 343     for (GList *iter = scheduler->ordering_constraints; iter != NULL;
 344          iter = iter->next) {
 345 
 346         pe__ordering_t *order = iter->data;
 347         uint32_t order_flags = pcmk__ar_ordered;
 348         GList *probes = NULL;
 349         GList *then_actions = NULL;
 350         pcmk_action_t *first = NULL;
 351         pcmk_action_t *then = NULL;
 352 
 353         // Skip disabled orderings
 354         if (order->flags == pcmk__ar_none) {
 355             continue;
 356         }
 357 
 358         // Skip non-resource orderings, and orderings for the same resource
 359         if ((order->lh_rsc == NULL) || (order->lh_rsc == order->rh_rsc)) {
 360             continue;
 361         }
 362 
 363         // Skip invalid orderings (shouldn't be possible)
 364         first = order->lh_action;
 365         then = order->rh_action;
 366         if (((first == NULL) && (order->lh_action_task == NULL))
 367             || ((then == NULL) && (order->rh_action_task == NULL))) {
 368             continue;
 369         }
 370 
 371         // Skip orderings for first actions other than stop
 372         if ((first != NULL) && !pcmk__str_eq(first->task, PCMK_ACTION_STOP,
 373                                              pcmk__str_none)) {
 374             continue;
 375         } else if ((first == NULL)
 376                    && !pcmk__ends_with(order->lh_action_task,
 377                                        "_" PCMK_ACTION_STOP "_0")) {
 378             continue;
 379         }
 380 
 381         /* Do not imply a probe ordering for a resource inside of a stopping
 382          * container. Otherwise, it might introduce a transition loop, since a
 383          * probe could be scheduled after the container starts again.
 384          */
 385         if ((order->rh_rsc != NULL)
 386             && (order->lh_rsc->container == order->rh_rsc)) {
 387 
 388             if ((then != NULL) && pcmk__str_eq(then->task, PCMK_ACTION_STOP,
 389                                                pcmk__str_none)) {
 390                 continue;
 391             } else if ((then == NULL)
 392                        && pcmk__ends_with(order->rh_action_task,
 393                                           "_" PCMK_ACTION_STOP "_0")) {
 394                 continue;
 395             }
 396         }
 397 
 398         // Preserve certain order options for future filtering
 399         if (pcmk_is_set(order->flags, pcmk__ar_if_first_unmigratable)) {
 400             pe__set_order_flags(order_flags, pcmk__ar_if_first_unmigratable);
 401         }
 402         if (pcmk_is_set(order->flags, pcmk__ar_if_on_same_node)) {
 403             pe__set_order_flags(order_flags, pcmk__ar_if_on_same_node);
 404         }
 405 
 406         // Preserve certain order types for future filtering
 407         if ((order->flags == pcmk__ar_if_required_on_same_node)
 408             || (order->flags == pcmk__ar_if_on_same_node_or_target)) {
 409             order_flags = order->flags;
 410         }
 411 
 412         // List all scheduled probes for the first resource
 413         probes = pe__resource_actions(order->lh_rsc, NULL, PCMK_ACTION_MONITOR,
 414                                       FALSE);
 415         if (probes == NULL) { // There aren't any
 416             continue;
 417         }
 418 
 419         // List all relevant "then" actions
 420         if (then != NULL) {
 421             then_actions = g_list_prepend(NULL, then);
 422 
 423         } else if (order->rh_rsc != NULL) {
 424             then_actions = find_actions(order->rh_rsc->actions,
 425                                         order->rh_action_task, NULL);
 426             if (then_actions == NULL) { // There aren't any
 427                 g_list_free(probes);
 428                 continue;
 429             }
 430         }
 431 
 432         crm_trace("Implying 'probe then' orderings for '%s then %s' "
 433                   "(id=%d, type=%.6x)",
 434                   ((first == NULL)? order->lh_action_task : first->uuid),
 435                   ((then == NULL)? order->rh_action_task : then->uuid),
 436                   order->id, order->flags);
 437 
 438         for (GList *probe_iter = probes; probe_iter != NULL;
 439              probe_iter = probe_iter->next) {
 440 
 441             pcmk_action_t *probe = (pcmk_action_t *) probe_iter->data;
 442 
 443             for (GList *then_iter = then_actions; then_iter != NULL;
 444                  then_iter = then_iter->next) {
 445 
 446                 pcmk_action_t *then = (pcmk_action_t *) then_iter->data;
 447 
 448                 if (probe_needed_before_action(probe, then)) {
 449                     order_actions(probe, then, order_flags);
 450                 }
 451             }
 452         }
 453 
 454         g_list_free(then_actions);
 455         g_list_free(probes);
 456     }
 457 }
 458 
 459 /*!
 460  * \internal
 461  * \brief Add necessary orderings between probe and starts of clone instances
 462  *
 463  * , in additon to the ordering with the parent resource added upon creating
 464  * the probe.
 465  *
 466  * \param[in,out] probe     Probe as 'first' action in an ordering
 467  * \param[in,out] after     'then' action wrapper in the ordering
 468  */
 469 static void
 470 add_start_orderings_for_probe(pcmk_action_t *probe,
     /*  */
 471                               pcmk__related_action_t *after)
 472 {
 473     uint32_t flags = pcmk__ar_ordered|pcmk__ar_unrunnable_first_blocks;
 474 
 475     /* Although the ordering between the probe of the clone instance and the
 476      * start of its parent has been added in pcmk__probe_rsc_on_node(), we
 477      * avoided enforcing `pcmk__ar_unrunnable_first_blocks` order type for that
 478      * as long as any of the clone instances are running to prevent them from
 479      * being unexpectedly stopped.
 480      *
 481      * On the other hand, we still need to prevent any inactive instances from
 482      * starting unless the probe is runnable so that we don't risk starting too
 483      * many instances before we know the state on all nodes.
 484      */
 485     if ((after->action->rsc->variant <= pcmk_rsc_variant_group)
 486         || pcmk_is_set(probe->flags, pcmk_action_runnable)
 487         // The order type is already enforced for its parent.
 488         || pcmk_is_set(after->type, pcmk__ar_unrunnable_first_blocks)
 489         || (pe__const_top_resource(probe->rsc, false) != after->action->rsc)
 490         || !pcmk__str_eq(after->action->task, PCMK_ACTION_START,
 491                          pcmk__str_none)) {
 492         return;
 493     }
 494 
 495     crm_trace("Adding probe start orderings for 'unrunnable %s@%s "
 496               "then instances of %s@%s'",
 497               probe->uuid, pe__node_name(probe->node),
 498               after->action->uuid, pe__node_name(after->action->node));
 499 
 500     for (GList *then_iter = after->action->actions_after; then_iter != NULL;
 501          then_iter = then_iter->next) {
 502 
 503         pcmk__related_action_t *then = then_iter->data;
 504 
 505         if (then->action->rsc->running_on
 506             || (pe__const_top_resource(then->action->rsc, false)
 507                 != after->action->rsc)
 508             || !pcmk__str_eq(then->action->task, PCMK_ACTION_START,
 509                              pcmk__str_none)) {
 510             continue;
 511         }
 512 
 513         crm_trace("Adding probe start ordering for 'unrunnable %s@%s "
 514                   "then %s@%s' (type=%#.6x)",
 515                   probe->uuid, pe__node_name(probe->node),
 516                   then->action->uuid, pe__node_name(then->action->node), flags);
 517 
 518         /* Prevent the instance from starting if the instance can't, but don't
 519          * cause any other intances to stop if already active.
 520          */
 521         order_actions(probe, then->action, flags);
 522     }
 523 
 524     return;
 525 }
 526 
 527 /*!
 528  * \internal
 529  * \brief Order probes before restarts and re-promotes
 530  *
 531  * If a given ordering is a "probe then start" or "probe then promote" ordering,
 532  * add an implicit "probe then stop/demote" ordering in case the action is part
 533  * of a restart/re-promote, and do the same recursively for all actions ordered
 534  * after the "then" action.
 535  *
 536  * \param[in,out] probe     Probe as 'first' action in an ordering
 537  * \param[in,out] after     'then' action in the ordering
 538  */
 539 static void
 540 add_restart_orderings_for_probe(pcmk_action_t *probe, pcmk_action_t *after)
     /*  */
 541 {
 542     GList *iter = NULL;
 543     bool interleave = false;
 544     pcmk_resource_t *compatible_rsc = NULL;
 545 
 546     // Validate that this is a resource probe followed by some action
 547     if ((after == NULL) || (probe == NULL) || (probe->rsc == NULL)
 548         || (probe->rsc->variant != pcmk_rsc_variant_primitive)
 549         || !pcmk__str_eq(probe->task, PCMK_ACTION_MONITOR, pcmk__str_none)) {
 550         return;
 551     }
 552 
 553     // Avoid running into any possible loop
 554     if (pcmk_is_set(after->flags, pcmk_action_detect_loop)) {
 555         return;
 556     }
 557     pe__set_action_flags(after, pcmk_action_detect_loop);
 558 
 559     crm_trace("Adding probe restart orderings for '%s@%s then %s@%s'",
 560               probe->uuid, pe__node_name(probe->node),
 561               after->uuid, pe__node_name(after->node));
 562 
 563     /* Add restart orderings if "then" is for a different primitive.
 564      * Orderings for collective resources will be added later.
 565      */
 566     if ((after->rsc != NULL)
 567         && (after->rsc->variant == pcmk_rsc_variant_primitive)
 568         && (probe->rsc != after->rsc)) {
 569 
 570             GList *then_actions = NULL;
 571 
 572             if (pcmk__str_eq(after->task, PCMK_ACTION_START, pcmk__str_none)) {
 573                 then_actions = pe__resource_actions(after->rsc, NULL,
 574                                                     PCMK_ACTION_STOP, FALSE);
 575 
 576             } else if (pcmk__str_eq(after->task, PCMK_ACTION_PROMOTE,
 577                                     pcmk__str_none)) {
 578                 then_actions = pe__resource_actions(after->rsc, NULL,
 579                                                     PCMK_ACTION_DEMOTE, FALSE);
 580             }
 581 
 582             for (iter = then_actions; iter != NULL; iter = iter->next) {
 583                 pcmk_action_t *then = (pcmk_action_t *) iter->data;
 584 
 585                 // Skip pseudo-actions (for example, those implied by fencing)
 586                 if (!pcmk_is_set(then->flags, pcmk_action_pseudo)) {
 587                     order_actions(probe, then, pcmk__ar_ordered);
 588                 }
 589             }
 590             g_list_free(then_actions);
 591     }
 592 
 593     /* Detect whether "then" is an interleaved clone action. For these, we want
 594      * to add orderings only for the relevant instance.
 595      */
 596     if ((after->rsc != NULL)
 597         && (after->rsc->variant > pcmk_rsc_variant_group)) {
 598         const char *interleave_s = g_hash_table_lookup(after->rsc->meta,
 599                                                        XML_RSC_ATTR_INTERLEAVE);
 600 
 601         interleave = crm_is_true(interleave_s);
 602         if (interleave) {
 603             compatible_rsc = pcmk__find_compatible_instance(probe->rsc,
 604                                                             after->rsc,
 605                                                             pcmk_role_unknown,
 606                                                             false);
 607         }
 608     }
 609 
 610     /* Now recursively do the same for all actions ordered after "then". This
 611      * also handles collective resources since the collective action will be
 612      * ordered before its individual instances' actions.
 613      */
 614     for (iter = after->actions_after; iter != NULL; iter = iter->next) {
 615         pcmk__related_action_t *after_wrapper = iter->data;
 616 
 617         /* pcmk__ar_first_implies_then is the reason why a required A.start
 618          * implies/enforces B.start to be required too, which is the cause of
 619          * B.restart/re-promote.
 620          *
 621          * Not sure about pcmk__ar_first_implies_same_node_then though. It's now
 622          * only used for unfencing case, which tends to introduce transition
 623          * loops...
 624          */
 625         if (!pcmk_is_set(after_wrapper->type, pcmk__ar_first_implies_then)) {
 626             /* The order type between a group/clone and its child such as
 627              * B.start-> B_child.start is:
 628              * pcmk__ar_then_implies_first_graphed
 629              * |pcmk__ar_unrunnable_first_blocks
 630              *
 631              * Proceed through the ordering chain and build dependencies with
 632              * its children.
 633              */
 634             if ((after->rsc == NULL)
 635                 || (after->rsc->variant < pcmk_rsc_variant_group)
 636                 || (probe->rsc->parent == after->rsc)
 637                 || (after_wrapper->action->rsc == NULL)
 638                 || (after_wrapper->action->rsc->variant > pcmk_rsc_variant_group)
 639                 || (after->rsc != after_wrapper->action->rsc->parent)) {
 640                 continue;
 641             }
 642 
 643             /* Proceed to the children of a group or a non-interleaved clone.
 644              * For an interleaved clone, proceed only to the relevant child.
 645              */
 646             if ((after->rsc->variant > pcmk_rsc_variant_group) && interleave
 647                 && ((compatible_rsc == NULL)
 648                     || (compatible_rsc != after_wrapper->action->rsc))) {
 649                 continue;
 650             }
 651         }
 652 
 653         crm_trace("Recursively adding probe restart orderings for "
 654                   "'%s@%s then %s@%s' (type=%#.6x)",
 655                   after->uuid, pe__node_name(after->node),
 656                   after_wrapper->action->uuid,
 657                   pe__node_name(after_wrapper->action->node),
 658                   after_wrapper->type);
 659 
 660         add_restart_orderings_for_probe(probe, after_wrapper->action);
 661     }
 662 }
 663 
 664 /*!
 665  * \internal
 666  * \brief Clear the tracking flag on all scheduled actions
 667  *
 668  * \param[in,out] scheduler  Scheduler data
 669  */
 670 static void
 671 clear_actions_tracking_flag(pcmk_scheduler_t *scheduler)
     /*  */
 672 {
 673     for (GList *iter = scheduler->actions; iter != NULL; iter = iter->next) {
 674         pcmk_action_t *action = iter->data;
 675 
 676         pe__clear_action_flags(action, pcmk_action_detect_loop);
 677     }
 678 }
 679 
 680 /*!
 681  * \internal
 682  * \brief Add start and restart orderings for probes scheduled for a resource
 683  *
 684  * \param[in,out] data       Resource whose probes should be ordered
 685  * \param[in]     user_data  Unused
 686  */
 687 static void
 688 add_start_restart_orderings_for_rsc(gpointer data, gpointer user_data)
     /*  */
 689 {
 690     pcmk_resource_t *rsc = data;
 691     GList *probes = NULL;
 692 
 693     // For collective resources, order each instance recursively
 694     if (rsc->variant != pcmk_rsc_variant_primitive) {
 695         g_list_foreach(rsc->children, add_start_restart_orderings_for_rsc,
 696                        NULL);
 697         return;
 698     }
 699 
 700     // Find all probes for given resource
 701     probes = pe__resource_actions(rsc, NULL, PCMK_ACTION_MONITOR, FALSE);
 702 
 703     // Add probe restart orderings for each probe found
 704     for (GList *iter = probes; iter != NULL; iter = iter->next) {
 705         pcmk_action_t *probe = (pcmk_action_t *) iter->data;
 706 
 707         for (GList *then_iter = probe->actions_after; then_iter != NULL;
 708              then_iter = then_iter->next) {
 709 
 710             pcmk__related_action_t *then = then_iter->data;
 711 
 712             add_start_orderings_for_probe(probe, then);
 713             add_restart_orderings_for_probe(probe, then->action);
 714             clear_actions_tracking_flag(rsc->cluster);
 715         }
 716     }
 717 
 718     g_list_free(probes);
 719 }
 720 
 721 /*!
 722  * \internal
 723  * \brief Add "A then probe B" orderings for "A then B" orderings
 724  *
 725  * \param[in,out] scheduler  Scheduler data
 726  *
 727  * \note This function is currently disabled (see next comment).
 728  */
 729 static void
 730 order_then_probes(pcmk_scheduler_t *scheduler)
     /*  */
 731 {
 732 #if 0
 733     /* Given an ordering "A then B", we would prefer to wait for A to be started
 734      * before probing B.
 735      *
 736      * For example, if A is a filesystem which B can't even run without, it
 737      * would be helpful if the author of B's agent could assume that A is
 738      * running before B.monitor will be called.
 739      *
 740      * However, we can't _only_ probe after A is running, otherwise we wouldn't
 741      * detect the state of B if A could not be started. We can't even do an
 742      * opportunistic version of this, because B may be moving:
 743      *
 744      *   A.stop -> A.start -> B.probe -> B.stop -> B.start
 745      *
 746      * and if we add B.stop -> A.stop here, we get a loop:
 747      *
 748      *   A.stop -> A.start -> B.probe -> B.stop -> A.stop
 749      *
 750      * We could kill the "B.probe -> B.stop" dependency, but that could mean
 751      * stopping B "too" soon, because B.start must wait for the probe, and
 752      * we don't want to stop B if we can't start it.
 753      *
 754      * We could add the ordering only if A is an anonymous clone with
 755      * clone-max == node-max (since we'll never be moving it). However, we could
 756      * still be stopping one instance at the same time as starting another.
 757      *
 758      * The complexity of checking for allowed conditions combined with the ever
 759      * narrowing use case suggests that this code should remain disabled until
 760      * someone gets smarter.
 761      */
 762     for (GList *iter = scheduler->resources; iter != NULL; iter = iter->next) {
 763         pcmk_resource_t *rsc = (pcmk_resource_t *) iter->data;
 764 
 765         pcmk_action_t *start = NULL;
 766         GList *actions = NULL;
 767         GList *probes = NULL;
 768 
 769         actions = pe__resource_actions(rsc, NULL, PCMK_ACTION_START, FALSE);
 770 
 771         if (actions) {
 772             start = actions->data;
 773             g_list_free(actions);
 774         }
 775 
 776         if (start == NULL) {
 777             crm_err("No start action for %s", rsc->id);
 778             continue;
 779         }
 780 
 781         probes = pe__resource_actions(rsc, NULL, PCMK_ACTION_MONITOR, FALSE);
 782 
 783         for (actions = start->actions_before; actions != NULL;
 784              actions = actions->next) {
 785 
 786             pcmk__related_action_t *before = actions->data;
 787 
 788             pcmk_action_t *first = before->action;
 789             pcmk_resource_t *first_rsc = first->rsc;
 790 
 791             if (first->required_runnable_before) {
 792                 for (GList *clone_actions = first->actions_before;
 793                      clone_actions != NULL;
 794                      clone_actions = clone_actions->next) {
 795 
 796                     before = clone_actions->data;
 797 
 798                     crm_trace("Testing '%s then %s' for %s",
 799                               first->uuid, before->action->uuid, start->uuid);
 800 
 801                     CRM_ASSERT(before->action->rsc != NULL);
 802                     first_rsc = before->action->rsc;
 803                     break;
 804                 }
 805 
 806             } else if (!pcmk__str_eq(first->task, PCMK_ACTION_START,
 807                                      pcmk__str_none)) {
 808                 crm_trace("Not a start op %s for %s", first->uuid, start->uuid);
 809             }
 810 
 811             if (first_rsc == NULL) {
 812                 continue;
 813 
 814             } else if (pe__const_top_resource(first_rsc, false)
 815                        == pe__const_top_resource(start->rsc, false)) {
 816                 crm_trace("Same parent %s for %s", first_rsc->id, start->uuid);
 817                 continue;
 818 
 819             } else if (!pe_rsc_is_clone(pe__const_top_resource(first_rsc,
 820                                                                false))) {
 821                 crm_trace("Not a clone %s for %s", first_rsc->id, start->uuid);
 822                 continue;
 823             }
 824 
 825             crm_err("Applying %s before %s %d", first->uuid, start->uuid,
 826                     pe__const_top_resource(first_rsc, false)->variant);
 827 
 828             for (GList *probe_iter = probes; probe_iter != NULL;
 829                  probe_iter = probe_iter->next) {
 830 
 831                 pcmk_action_t *probe = (pcmk_action_t *) probe_iter->data;
 832 
 833                 crm_err("Ordering %s before %s", first->uuid, probe->uuid);
 834                 order_actions(first, probe, pcmk__ar_ordered);
 835             }
 836         }
 837     }
 838 #endif
 839 }
 840 
 841 void
 842 pcmk__order_probes(pcmk_scheduler_t *scheduler)
     /*  */
 843 {
 844     // Add orderings for "probe then X"
 845     g_list_foreach(scheduler->resources, add_start_restart_orderings_for_rsc,
 846                    NULL);
 847     add_probe_orderings_for_stops(scheduler);
 848 
 849     order_then_probes(scheduler);
 850 }
 851 
 852 /*!
 853  * \internal
 854  * \brief Schedule any probes needed
 855  *
 856  * \param[in,out] scheduler  Scheduler data
 857  *
 858  * \note This may also schedule fencing of failed remote nodes.
 859  */
 860 void
 861 pcmk__schedule_probes(pcmk_scheduler_t *scheduler)
     /*  */
 862 {
 863     // Schedule probes on each node in the cluster as needed
 864     for (GList *iter = scheduler->nodes; iter != NULL; iter = iter->next) {
 865         pcmk_node_t *node = (pcmk_node_t *) iter->data;
 866         const char *probed = NULL;
 867 
 868         if (!node->details->online) { // Don't probe offline nodes
 869             if (pcmk__is_failed_remote_node(node)) {
 870                 pe_fence_node(scheduler, node,
 871                               "the connection is unrecoverable", FALSE);
 872             }
 873             continue;
 874 
 875         } else if (node->details->unclean) { // ... or nodes that need fencing
 876             continue;
 877 
 878         } else if (!node->details->rsc_discovery_enabled) {
 879             // The user requested that probes not be done on this node
 880             continue;
 881         }
 882 
 883         /* This is no longer needed for live clusters, since the probe_complete
 884          * node attribute will never be in the CIB. However this is still useful
 885          * for processing old saved CIBs (< 1.1.14), including the
 886          * reprobe-target_rc regression test.
 887          */
 888         probed = pe_node_attribute_raw(node, CRM_OP_PROBED);
 889         if (probed != NULL && crm_is_true(probed) == FALSE) {
 890             pcmk_action_t *probe_op = NULL;
 891 
 892             probe_op = custom_action(NULL,
 893                                      crm_strdup_printf("%s-%s", CRM_OP_REPROBE,
 894                                                        node->details->uname),
 895                                      CRM_OP_REPROBE, node, FALSE, scheduler);
 896             add_hash_param(probe_op->meta, XML_ATTR_TE_NOWAIT,
 897                            XML_BOOLEAN_TRUE);
 898             continue;
 899         }
 900 
 901         // Probe each resource in the cluster on this node, as needed
 902         pcmk__probe_resource_list(scheduler->resources, node);
 903     }
 904 }

/* */