pcmk_sched_group.c

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/*
 * Copyright 2004-2024 the Pacemaker project contributors
 *
 * The version control history for this file may have further details.
 *
 * This source code is licensed under the GNU General Public License version 2
 * or later (GPLv2+) WITHOUT ANY WARRANTY.
 */
 
#include <crm_internal.h>
 
#include <stdbool.h>
 
#include <crm/common/xml.h>
 
#include <pacemaker-internal.h>
#include "libpacemaker_private.h"
 
pcmk_node_t *
pcmk__group_assign(pcmk_resource_t *rsc, const pcmk_node_t *prefer,
                   bool stop_if_fail)
{
    pcmk_node_t *first_assigned_node = NULL;
    pcmk_resource_t *first_member = NULL;
 
    CRM_ASSERT(pcmk__is_group(rsc));
 
    if (!pcmk_is_set(rsc->flags, pcmk_rsc_unassigned)) {
        return rsc->allocated_to; // Assignment already done
    }
    if (pcmk_is_set(rsc->flags, pcmk_rsc_assigning)) {
        pcmk__rsc_debug(rsc, "Assignment dependency loop detected involving %s",
                        rsc->id);
        return NULL;
    }
 
    if (rsc->children == NULL) {
        // No members to assign
        pcmk__clear_rsc_flags(rsc, pcmk_rsc_unassigned);
        return NULL;
    }
 
    pcmk__set_rsc_flags(rsc, pcmk_rsc_assigning);
    first_member = (pcmk_resource_t *) rsc->children->data;
    rsc->role = first_member->role;
 
    pe__show_node_scores(!pcmk_is_set(rsc->cluster->flags,
                                      pcmk_sched_output_scores),
                         rsc, __func__, rsc->allowed_nodes, rsc->cluster);
 
    for (GList *iter = rsc->children; iter != NULL; iter = iter->next) {
        pcmk_resource_t *member = (pcmk_resource_t *) iter->data;
        pcmk_node_t *node = NULL;
 
        pcmk__rsc_trace(rsc, "Assigning group %s member %s",
                        rsc->id, member->id);
        node = member->cmds->assign(member, prefer, stop_if_fail);
        if (first_assigned_node == NULL) {
            first_assigned_node = node;
        }
    }
 
    pe__set_next_role(rsc, first_member->next_role, "first group member");
    pcmk__clear_rsc_flags(rsc, pcmk_rsc_assigning|pcmk_rsc_unassigned);
 
    if (!pe__group_flag_is_set(rsc, pcmk__group_colocated)) {
        return NULL;
    }
    return first_assigned_node;
}
 
static pcmk_action_t *
create_group_pseudo_op(pcmk_resource_t *group, const char *action)
{
    pcmk_action_t *op = custom_action(group, pcmk__op_key(group->id, action, 0),
                                      action, NULL, TRUE, group->cluster);
 
    pcmk__set_action_flags(op, pcmk_action_pseudo|pcmk_action_runnable);
    return op;
}
 
void
pcmk__group_create_actions(pcmk_resource_t *rsc)
{
    CRM_ASSERT(pcmk__is_group(rsc));
 
    pcmk__rsc_trace(rsc, "Creating actions for group %s", rsc->id);
 
    // Create actions for individual group members
    for (GList *iter = rsc->children; iter != NULL; iter = iter->next) {
        pcmk_resource_t *member = (pcmk_resource_t *) iter->data;
 
        member->cmds->create_actions(member);
    }
 
    // Create pseudo-actions for group itself to serve as ordering points
    create_group_pseudo_op(rsc, PCMK_ACTION_START);
    create_group_pseudo_op(rsc, PCMK_ACTION_RUNNING);
    create_group_pseudo_op(rsc, PCMK_ACTION_STOP);
    create_group_pseudo_op(rsc, PCMK_ACTION_STOPPED);
    if (crm_is_true(g_hash_table_lookup(rsc->meta, PCMK_META_PROMOTABLE))) {
        create_group_pseudo_op(rsc, PCMK_ACTION_DEMOTE);
        create_group_pseudo_op(rsc, PCMK_ACTION_DEMOTED);
        create_group_pseudo_op(rsc, PCMK_ACTION_PROMOTE);
        create_group_pseudo_op(rsc, PCMK_ACTION_PROMOTED);
    }
}
 
// User data for member_internal_constraints()
struct member_data {
    // These could be derived from member but this avoids some function calls
    bool ordered;
    bool colocated;
    bool promotable;
 
    pcmk_resource_t *last_active;
    pcmk_resource_t *previous_member;
};
 
static void
member_internal_constraints(gpointer data, gpointer user_data)
{
    pcmk_resource_t *member = (pcmk_resource_t *) data;
    struct member_data *member_data = (struct member_data *) user_data;
 
    // For ordering demote vs demote or stop vs stop
    uint32_t down_flags = pcmk__ar_then_implies_first_graphed;
 
    // For ordering demote vs demoted or stop vs stopped
    uint32_t post_down_flags = pcmk__ar_first_implies_then_graphed;
 
    // Create the individual member's implicit constraints
    member->cmds->internal_constraints(member);
 
    if (member_data->previous_member == NULL) {
        // This is first member
        if (member_data->ordered) {
            pcmk__set_relation_flags(down_flags, pcmk__ar_ordered);
            post_down_flags = pcmk__ar_first_implies_then;
        }
 
    } else if (member_data->colocated) {
        uint32_t flags = pcmk__coloc_none;
 
        if (pcmk_is_set(member->flags, pcmk_rsc_critical)) {
            flags |= pcmk__coloc_influence;
        }
 
        // Colocate this member with the previous one
        pcmk__new_colocation("#group-members", NULL, PCMK_SCORE_INFINITY,
                             member, member_data->previous_member, NULL, NULL,
                             flags);
    }
 
    if (member_data->promotable) {
        // Demote group -> demote member -> group is demoted
        pcmk__order_resource_actions(member->parent, PCMK_ACTION_DEMOTE,
                                     member, PCMK_ACTION_DEMOTE, down_flags);
        pcmk__order_resource_actions(member, PCMK_ACTION_DEMOTE,
                                     member->parent, PCMK_ACTION_DEMOTED,
                                     post_down_flags);
 
        // Promote group -> promote member -> group is promoted
        pcmk__order_resource_actions(member, PCMK_ACTION_PROMOTE,
                                     member->parent, PCMK_ACTION_PROMOTED,
                                     pcmk__ar_unrunnable_first_blocks
                                     |pcmk__ar_first_implies_then
                                     |pcmk__ar_first_implies_then_graphed);
        pcmk__order_resource_actions(member->parent, PCMK_ACTION_PROMOTE,
                                     member, PCMK_ACTION_PROMOTE,
                                     pcmk__ar_then_implies_first_graphed);
    }
 
    // Stop group -> stop member -> group is stopped
    pcmk__order_stops(member->parent, member, down_flags);
    pcmk__order_resource_actions(member, PCMK_ACTION_STOP,
                                 member->parent, PCMK_ACTION_STOPPED,
                                 post_down_flags);
 
    // Start group -> start member -> group is started
    pcmk__order_starts(member->parent, member,
                       pcmk__ar_then_implies_first_graphed);
    pcmk__order_resource_actions(member, PCMK_ACTION_START,
                                 member->parent, PCMK_ACTION_RUNNING,
                                 pcmk__ar_unrunnable_first_blocks
                                 |pcmk__ar_first_implies_then
                                 |pcmk__ar_first_implies_then_graphed);
 
    if (!member_data->ordered) {
        pcmk__order_starts(member->parent, member,
                           pcmk__ar_first_implies_then
                           |pcmk__ar_unrunnable_first_blocks
                           |pcmk__ar_then_implies_first_graphed);
        if (member_data->promotable) {
            pcmk__order_resource_actions(member->parent, PCMK_ACTION_PROMOTE,
                                         member, PCMK_ACTION_PROMOTE,
                                         pcmk__ar_first_implies_then
                                         |pcmk__ar_unrunnable_first_blocks
                                         |pcmk__ar_then_implies_first_graphed);
        }
 
    } else if (member_data->previous_member == NULL) {
        pcmk__order_starts(member->parent, member, pcmk__ar_none);
        if (member_data->promotable) {
            pcmk__order_resource_actions(member->parent, PCMK_ACTION_PROMOTE,
                                         member, PCMK_ACTION_PROMOTE,
                                         pcmk__ar_none);
        }
 
    } else {
        // Order this member relative to the previous one
 
        pcmk__order_starts(member_data->previous_member, member,
                           pcmk__ar_first_implies_then
                           |pcmk__ar_unrunnable_first_blocks);
        pcmk__order_stops(member, member_data->previous_member,
                          pcmk__ar_ordered|pcmk__ar_intermediate_stop);
 
        /* In unusual circumstances (such as adding a new member to the middle
         * of a group with unmanaged later members), this member may be active
         * while the previous (new) member is inactive. In this situation, the
         * usual restart orderings will be irrelevant, so we need to order this
         * member's stop before the previous member's start.
         */
        if ((member->running_on != NULL)
            && (member_data->previous_member->running_on == NULL)) {
            pcmk__order_resource_actions(member, PCMK_ACTION_STOP,
                                         member_data->previous_member,
                                         PCMK_ACTION_START,
                                         pcmk__ar_then_implies_first
                                         |pcmk__ar_unrunnable_first_blocks);
        }
 
        if (member_data->promotable) {
            pcmk__order_resource_actions(member_data->previous_member,
                                         PCMK_ACTION_PROMOTE, member,
                                         PCMK_ACTION_PROMOTE,
                                         pcmk__ar_first_implies_then
                                         |pcmk__ar_unrunnable_first_blocks);
            pcmk__order_resource_actions(member, PCMK_ACTION_DEMOTE,
                                         member_data->previous_member,
                                         PCMK_ACTION_DEMOTE, pcmk__ar_ordered);
        }
    }
 
    // Make sure partially active groups shut down in sequence
    if (member->running_on != NULL) {
        if (member_data->ordered && (member_data->previous_member != NULL)
            && (member_data->previous_member->running_on == NULL)
            && (member_data->last_active != NULL)
            && (member_data->last_active->running_on != NULL)) {
            pcmk__order_stops(member, member_data->last_active,
                              pcmk__ar_ordered);
        }
        member_data->last_active = member;
    }
 
    member_data->previous_member = member;
}
 
void
pcmk__group_internal_constraints(pcmk_resource_t *rsc)
{
    struct member_data member_data = { false, };
    const pcmk_resource_t *top = NULL;
 
    CRM_ASSERT(pcmk__is_group(rsc));
 
    /* Order group pseudo-actions relative to each other for restarting:
     * stop group -> group is stopped -> start group -> group is started
     */
    pcmk__order_resource_actions(rsc, PCMK_ACTION_STOP,
                                 rsc, PCMK_ACTION_STOPPED,
                                 pcmk__ar_unrunnable_first_blocks);
    pcmk__order_resource_actions(rsc, PCMK_ACTION_STOPPED,
                                 rsc, PCMK_ACTION_START,
                                 pcmk__ar_ordered);
    pcmk__order_resource_actions(rsc, PCMK_ACTION_START,
                                 rsc, PCMK_ACTION_RUNNING,
                                 pcmk__ar_unrunnable_first_blocks);
 
    top = pe__const_top_resource(rsc, false);
 
    member_data.ordered = pe__group_flag_is_set(rsc, pcmk__group_ordered);
    member_data.colocated = pe__group_flag_is_set(rsc, pcmk__group_colocated);
    member_data.promotable = pcmk_is_set(top->flags, pcmk_rsc_promotable);
    g_list_foreach(rsc->children, member_internal_constraints, &member_data);
}
 
static void
colocate_group_with(pcmk_resource_t *dependent, const pcmk_resource_t *primary,
                    const pcmk__colocation_t *colocation)
{
    pcmk_resource_t *member = NULL;
 
    if (dependent->children == NULL) {
        return;
    }
 
    pcmk__rsc_trace(primary, "Processing %s (group %s with %s) for dependent",
                    colocation->id, dependent->id, primary->id);
 
    if (pe__group_flag_is_set(dependent, pcmk__group_colocated)) {
        // Colocate first member (internal colocations will handle the rest)
        member = (pcmk_resource_t *) dependent->children->data;
        member->cmds->apply_coloc_score(member, primary, colocation, true);
        return;
    }
 
    if (colocation->score >= PCMK_SCORE_INFINITY) {
        pcmk__config_err("%s: Cannot perform mandatory colocation between "
                         "non-colocated group and %s",
                         dependent->id, primary->id);
        return;
    }
 
    // Colocate each member individually
    for (GList *iter = dependent->children; iter != NULL; iter = iter->next) {
        member = (pcmk_resource_t *) iter->data;
        member->cmds->apply_coloc_score(member, primary, colocation, true);
    }
}
 
static void
colocate_with_group(pcmk_resource_t *dependent, const pcmk_resource_t *primary,
                    const pcmk__colocation_t *colocation)
{
    const pcmk_resource_t *member = NULL;
 
    pcmk__rsc_trace(primary,
                    "Processing colocation %s (%s with group %s) for primary",
                    colocation->id, dependent->id, primary->id);
 
    if (pcmk_is_set(primary->flags, pcmk_rsc_unassigned)) {
        return;
    }
 
    if (pe__group_flag_is_set(primary, pcmk__group_colocated)) {
 
        if (colocation->score >= PCMK_SCORE_INFINITY) {
            /* For mandatory colocations, the entire group must be assignable
             * (and in the specified role if any), so apply the colocation based
             * on the last member.
             */
            member = pe__last_group_member(primary);
        } else if (primary->children != NULL) {
            /* For optional colocations, whether the group is partially or fully
             * up doesn't matter, so apply the colocation based on the first
             * member.
             */
            member = (pcmk_resource_t *) primary->children->data;
        }
        if (member == NULL) {
            return; // Nothing to colocate with
        }
 
        member->cmds->apply_coloc_score(dependent, member, colocation, false);
        return;
    }
 
    if (colocation->score >= PCMK_SCORE_INFINITY) {
        pcmk__config_err("%s: Cannot perform mandatory colocation with"
                         " non-colocated group %s",
                         dependent->id, primary->id);
        return;
    }
 
    // Colocate dependent with each member individually
    for (const GList *iter = primary->children; iter != NULL;
         iter = iter->next) {
        member = iter->data;
        member->cmds->apply_coloc_score(dependent, member, colocation, false);
    }
}
 
void
pcmk__group_apply_coloc_score(pcmk_resource_t *dependent,
                              const pcmk_resource_t *primary,
                              const pcmk__colocation_t *colocation,
                              bool for_dependent)
{
    CRM_ASSERT((dependent != NULL) && (primary != NULL)
               && (colocation != NULL));
 
    if (for_dependent) {
        colocate_group_with(dependent, primary, colocation);
 
    } else {
        // Method should only be called for primitive dependents
        CRM_ASSERT(pcmk__is_primitive(dependent));
 
        colocate_with_group(dependent, primary, colocation);
    }
}
 
uint32_t
pcmk__group_action_flags(pcmk_action_t *action, const pcmk_node_t *node)
{
    // Default flags for a group action
    uint32_t flags = pcmk_action_optional
                     |pcmk_action_runnable
                     |pcmk_action_pseudo;
 
    CRM_ASSERT(action != NULL);
 
    // Update flags considering each member's own flags for same action
    for (GList *iter = action->rsc->children; iter != NULL; iter = iter->next) {
        pcmk_resource_t *member = (pcmk_resource_t *) iter->data;
 
        // Check whether member has the same action
        enum action_tasks task = get_complex_task(member, action->task);
        const char *task_s = pcmk_action_text(task);
        pcmk_action_t *member_action = find_first_action(member->actions, NULL,
                                                         task_s, node);
 
        if (member_action != NULL) {
            uint32_t member_flags = member->cmds->action_flags(member_action,
                                                               node);
 
            // Group action is mandatory if any member action is
            if (pcmk_is_set(flags, pcmk_action_optional)
                && !pcmk_is_set(member_flags, pcmk_action_optional)) {
                pcmk__rsc_trace(action->rsc, "%s is mandatory because %s is",
                                action->uuid, member_action->uuid);
                pcmk__clear_raw_action_flags(flags, "group action",
                                             pcmk_action_optional);
                pcmk__clear_action_flags(action, pcmk_action_optional);
            }
 
            // Group action is unrunnable if any member action is
            if (!pcmk__str_eq(task_s, action->task, pcmk__str_none)
                && pcmk_is_set(flags, pcmk_action_runnable)
                && !pcmk_is_set(member_flags, pcmk_action_runnable)) {
 
                pcmk__rsc_trace(action->rsc, "%s is unrunnable because %s is",
                                action->uuid, member_action->uuid);
                pcmk__clear_raw_action_flags(flags, "group action",
                                             pcmk_action_runnable);
                pcmk__clear_action_flags(action, pcmk_action_runnable);
            }
 
        /* Group (pseudo-)actions other than stop or demote are unrunnable
         * unless every member will do it.
         */
        } else if ((task != pcmk_action_stop) && (task != pcmk_action_demote)) {
            pcmk__rsc_trace(action->rsc,
                            "%s is not runnable because %s will not %s",
                            action->uuid, member->id, task_s);
            pcmk__clear_raw_action_flags(flags, "group action",
                                         pcmk_action_runnable);
        }
    }
 
    return flags;
}
 
uint32_t
pcmk__group_update_ordered_actions(pcmk_action_t *first, pcmk_action_t *then,
                                   const pcmk_node_t *node, uint32_t flags,
                                   uint32_t filter, uint32_t type,
                                   pcmk_scheduler_t *scheduler)
{
    uint32_t changed = pcmk__updated_none;
 
    // Group method can be called only on behalf of "then" action
    CRM_ASSERT((first != NULL) && (then != NULL) && (then->rsc != NULL)
               && (scheduler != NULL));
 
    // Update the actions for the group itself
    changed |= pcmk__update_ordered_actions(first, then, node, flags, filter,
                                            type, scheduler);
 
    // Update the actions for each group member
    for (GList *iter = then->rsc->children; iter != NULL; iter = iter->next) {
        pcmk_resource_t *member = (pcmk_resource_t *) iter->data;
 
        pcmk_action_t *member_action = find_first_action(member->actions, NULL,
                                                         then->task, node);
 
        if (member_action != NULL) {
            changed |= member->cmds->update_ordered_actions(first,
                                                            member_action, node,
                                                            flags, filter, type,
                                                            scheduler);
        }
    }
    return changed;
}
 
void
pcmk__group_apply_location(pcmk_resource_t *rsc, pcmk__location_t *location)
{
    GList *node_list_orig = NULL;
    GList *node_list_copy = NULL;
    bool reset_scores = true;
 
    CRM_ASSERT(pcmk__is_group(rsc) && (location != NULL));
 
    node_list_orig = location->nodes;
    node_list_copy = pcmk__copy_node_list(node_list_orig, true);
    reset_scores = pe__group_flag_is_set(rsc, pcmk__group_colocated);
 
    // Apply the constraint for the group itself (updates node scores)
    pcmk__apply_location(rsc, location);
 
    // Apply the constraint for each member
    for (GList *iter = rsc->children; iter != NULL; iter = iter->next) {
        pcmk_resource_t *member = (pcmk_resource_t *) iter->data;
 
        member->cmds->apply_location(member, location);
 
        if (reset_scores) {
            /* The first member of colocated groups needs to use the original
             * node scores, but subsequent members should work on a copy, since
             * the first member's scores already incorporate theirs.
             */
            reset_scores = false;
            location->nodes = node_list_copy;
        }
    }
 
    location->nodes = node_list_orig;
    g_list_free_full(node_list_copy, free);
}
 
// Group implementation of pcmk_assignment_methods_t:colocated_resources()
GList *
pcmk__group_colocated_resources(const pcmk_resource_t *rsc,
                                const pcmk_resource_t *orig_rsc,
                                GList *colocated_rscs)
{
    const pcmk_resource_t *member = NULL;
 
    CRM_ASSERT(pcmk__is_group(rsc));
 
    if (orig_rsc == NULL) {
        orig_rsc = rsc;
    }
 
    if (pe__group_flag_is_set(rsc, pcmk__group_colocated)
        || pcmk__is_clone(rsc->parent)) {
        /* This group has colocated members and/or is cloned -- either way,
         * add every child's colocated resources to the list. The first and last
         * members will include the group's own colocations.
         */
        colocated_rscs = g_list_prepend(colocated_rscs, (gpointer) rsc);
        for (const GList *iter = rsc->children;
             iter != NULL; iter = iter->next) {
 
            member = (const pcmk_resource_t *) iter->data;
            colocated_rscs = member->cmds->colocated_resources(member, orig_rsc,
                                                               colocated_rscs);
        }
 
    } else if (rsc->children != NULL) {
        /* This group's members are not colocated, and the group is not cloned,
         * so just add the group's own colocations to the list.
         */
        colocated_rscs = pcmk__colocated_resources(rsc, orig_rsc,
                                                   colocated_rscs);
    }
 
    return colocated_rscs;
}
 
// Group implementation of pcmk_assignment_methods_t:with_this_colocations()
void
pcmk__with_group_colocations(const pcmk_resource_t *rsc,
                             const pcmk_resource_t *orig_rsc, GList **list)
 
{
    CRM_ASSERT((orig_rsc != NULL) && (list != NULL) && pcmk__is_group(rsc));
 
    // Ignore empty groups
    if (rsc->children == NULL) {
        return;
    }
 
    /* "With this" colocations are needed only for the group itself and for its
     * last member. (Previous members will chain via the group internal
     * colocations.)
     */
    if ((orig_rsc != rsc) && (orig_rsc != pe__last_group_member(rsc))) {
        return;
    }
 
    pcmk__rsc_trace(rsc, "Adding 'with %s' colocations to list for %s",
                    rsc->id, orig_rsc->id);
 
    // Add the group's own colocations
    pcmk__add_with_this_list(list, rsc->rsc_cons_lhs, orig_rsc);
 
    // If cloned, add any relevant colocations with the clone
    if (rsc->parent != NULL) {
        rsc->parent->cmds->with_this_colocations(rsc->parent, orig_rsc,
                                                 list);
    }
 
    if (!pe__group_flag_is_set(rsc, pcmk__group_colocated)) {
        // @COMPAT Non-colocated groups are deprecated
        return;
    }
 
    // Add explicit colocations with the group's (other) children
    for (const GList *iter = rsc->children; iter != NULL; iter = iter->next) {
        const pcmk_resource_t *member = iter->data;
 
        if (member != orig_rsc) {
            member->cmds->with_this_colocations(member, orig_rsc, list);
        }
    }
}
 
// Group implementation of pcmk_assignment_methods_t:this_with_colocations()
void
pcmk__group_with_colocations(const pcmk_resource_t *rsc,
                             const pcmk_resource_t *orig_rsc, GList **list)
{
    const pcmk_resource_t *member = NULL;
 
    CRM_ASSERT((orig_rsc != NULL) && (list != NULL) && pcmk__is_group(rsc));
 
    // Ignore empty groups
    if (rsc->children == NULL) {
        return;
    }
 
    /* "This with" colocations are normally needed only for the group itself and
     * for its first member.
     */
    if ((rsc == orig_rsc)
        || (orig_rsc == (const pcmk_resource_t *) rsc->children->data)) {
        pcmk__rsc_trace(rsc, "Adding '%s with' colocations to list for %s",
                        rsc->id, orig_rsc->id);
 
        // Add the group's own colocations
        pcmk__add_this_with_list(list, rsc->rsc_cons, orig_rsc);
 
        // If cloned, add any relevant colocations involving the clone
        if (rsc->parent != NULL) {
            rsc->parent->cmds->this_with_colocations(rsc->parent, orig_rsc,
                                                     list);
        }
 
        if (!pe__group_flag_is_set(rsc, pcmk__group_colocated)) {
            // @COMPAT Non-colocated groups are deprecated
            return;
        }
 
        // Add explicit colocations involving the group's (other) children
        for (const GList *iter = rsc->children;
             iter != NULL; iter = iter->next) {
            member = iter->data;
            if (member != orig_rsc) {
                member->cmds->this_with_colocations(member, orig_rsc, list);
            }
        }
        return;
    }
 
    /* Later group members honor the group's colocations indirectly, due to the
     * internal group colocations that chain everything from the first member.
     * However, if an earlier group member is unmanaged, this chaining will not
     * happen, so the group's mandatory colocations must be explicitly added.
     */
    for (const GList *iter = rsc->children; iter != NULL; iter = iter->next) {
        member = iter->data;
        if (orig_rsc == member) {
            break; // We've seen all earlier members, and none are unmanaged
        }
 
        if (!pcmk_is_set(member->flags, pcmk_rsc_managed)) {
            crm_trace("Adding mandatory '%s with' colocations to list for "
                      "member %s because earlier member %s is unmanaged",
                      rsc->id, orig_rsc->id, member->id);
            for (const GList *cons_iter = rsc->rsc_cons; cons_iter != NULL;
                 cons_iter = cons_iter->next) {
                const pcmk__colocation_t *colocation = NULL;
 
                colocation = (const pcmk__colocation_t *) cons_iter->data;
                if (colocation->score == PCMK_SCORE_INFINITY) {
                    pcmk__add_this_with(list, colocation, orig_rsc);
                }
            }
            // @TODO Add mandatory (or all?) clone constraints if cloned
            break;
        }
    }
}
 
void
pcmk__group_add_colocated_node_scores(pcmk_resource_t *source_rsc,
                                      const pcmk_resource_t *target_rsc,
                                      const char *log_id, GHashTable **nodes,
                                      const pcmk__colocation_t *colocation,
                                      float factor, uint32_t flags)
{
    pcmk_resource_t *member = NULL;
 
    CRM_ASSERT(pcmk__is_group(source_rsc) && (nodes != NULL)
               && ((colocation != NULL)
                   || ((target_rsc == NULL) && (*nodes == NULL))));
 
    if (log_id == NULL) {
        log_id = source_rsc->id;
    }
 
    // Avoid infinite recursion
    if (pcmk_is_set(source_rsc->flags, pcmk_rsc_updating_nodes)) {
        pcmk__rsc_info(source_rsc, "%s: Breaking dependency loop at %s",
                       log_id, source_rsc->id);
        return;
    }
    pcmk__set_rsc_flags(source_rsc, pcmk_rsc_updating_nodes);
 
    // Ignore empty groups (only possible with schema validation disabled)
    if (source_rsc->children == NULL) {
        return;
    }
 
    /* Refer the operation to the first or last member as appropriate.
     *
     * cmp_resources() is the only caller that passes a NULL nodes table,
     * and is also the only caller using pcmk__coloc_select_this_with.
     * For "this with" colocations, the last member will recursively incorporate
     * all the other members' "this with" colocations via the internal group
     * colocations (and via the first member, the group's own colocations).
     *
     * For "with this" colocations, the first member works similarly.
     */
    if (*nodes == NULL) {
        member = pe__last_group_member(source_rsc);
    } else {
        member = source_rsc->children->data;
    }
    pcmk__rsc_trace(source_rsc, "%s: Merging scores from group %s using member %s "
                    "(at %.6f)", log_id, source_rsc->id, member->id, factor);
    member->cmds->add_colocated_node_scores(member, target_rsc, log_id, nodes,
                                            colocation, factor, flags);
    pcmk__clear_rsc_flags(source_rsc, pcmk_rsc_updating_nodes);
}
 
// Group implementation of pcmk_assignment_methods_t:add_utilization()
void
pcmk__group_add_utilization(const pcmk_resource_t *rsc,
                            const pcmk_resource_t *orig_rsc, GList *all_rscs,
                            GHashTable *utilization)
{
    pcmk_resource_t *member = NULL;
 
    CRM_ASSERT((orig_rsc != NULL) && (utilization != NULL)
               && pcmk__is_group(rsc));
 
    if (!pcmk_is_set(rsc->flags, pcmk_rsc_unassigned)) {
        return;
    }
 
    pcmk__rsc_trace(orig_rsc, "%s: Adding group %s as colocated utilization",
                    orig_rsc->id, rsc->id);
    if (pe__group_flag_is_set(rsc, pcmk__group_colocated)
        || pcmk__is_clone(rsc->parent)) {
        // Every group member will be on same node, so sum all members
        for (GList *iter = rsc->children; iter != NULL; iter = iter->next) {
            member = (pcmk_resource_t *) iter->data;
 
            if (pcmk_is_set(member->flags, pcmk_rsc_unassigned)
                && (g_list_find(all_rscs, member) == NULL)) {
                member->cmds->add_utilization(member, orig_rsc, all_rscs,
                                              utilization);
            }
        }
 
    } else if (rsc->children != NULL) {
        // Just add first member's utilization
        member = (pcmk_resource_t *) rsc->children->data;
        if ((member != NULL)
            && pcmk_is_set(member->flags, pcmk_rsc_unassigned)
            && (g_list_find(all_rscs, member) == NULL)) {
 
            member->cmds->add_utilization(member, orig_rsc, all_rscs,
                                          utilization);
        }
    }
}
 
void
pcmk__group_shutdown_lock(pcmk_resource_t *rsc)
{
    CRM_ASSERT(pcmk__is_group(rsc));
 
    for (GList *iter = rsc->children; iter != NULL; iter = iter->next) {
        pcmk_resource_t *member = (pcmk_resource_t *) iter->data;
 
        member->cmds->shutdown_lock(member);
    }
}