src/interfaces/select.c

/*****************************************************************************\
 *  select.c - resource selection plugin wrapper.
 *****************************************************************************
 *  Copyright (C) 2002-2007 The Regents of the University of California.
 *  Copyright (C) 2008-2009 Lawrence Livermore National Security.
 *  Produced at Lawrence Livermore National Laboratory (cf, DISCLAIMER).
 *  Written by Morris Jette <jette1@llnl.gov>.
 *  CODE-OCEC-09-009. All rights reserved.
 *
 *  This file is part of Slurm, a resource management program.
 *  For details, see <https://slurm.schedmd.com/>.
 *  Please also read the included file: DISCLAIMER.
 *
 *  Slurm 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.
 *
 *  In addition, as a special exception, the copyright holders give permission
 *  to link the code of portions of this program with the OpenSSL library under
 *  certain conditions as described in each individual source file, and
 *  distribute linked combinations including the two. You must obey the GNU
 *  General Public License in all respects for all of the code used other than
 *  OpenSSL. If you modify file(s) with this exception, you may extend this
 *  exception to your version of the file(s), but you are not obligated to do
 *  so. If you do not wish to do so, delete this exception statement from your
 *  version.  If you delete this exception statement from all source files in
 *  the program, then also delete it here.
 *
 *  Slurm is distributed in the hope that it will be useful, but WITHOUT ANY
 *  WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
 *  FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more
 *  details.
 *
 *  You should have received a copy of the GNU General Public License along
 *  with Slurm; if not, write to the Free Software Foundation, Inc.,
 *  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301  USA.
\*****************************************************************************/

#include "config.h"

#include <dirent.h>
#include <pthread.h>

#include "src/common/list.h"
#include "src/interfaces/select.h"
#include "src/common/slurm_protocol_api.h"
#include "src/common/xstring.h"
#include "src/slurmctld/slurmctld.h"

/*
 * Must be synchronized with slurm_select_ops_t in select.h.
 * Also must be synchronized with the other_select.c in
 * the select/other lib. (We tried to make it so we only had to
 * define it once, but it didn't seem to work.)
 */
const char *node_select_syms[] = {
	"plugin_id",
	"select_p_state_save",
	"select_p_state_restore",
	"select_p_job_init",
	"select_p_node_init",
	"select_p_job_test",
	"select_p_job_begin",
	"select_p_job_ready",
	"select_p_job_expand",
	"select_p_job_resized",
	"select_p_job_fini",
	"select_p_job_suspend",
	"select_p_job_resume",
	"select_p_step_pick_nodes",
	"select_p_step_start",
	"select_p_step_finish",
	"select_p_select_nodeinfo_pack",
	"select_p_select_nodeinfo_unpack",
	"select_p_select_nodeinfo_alloc",
	"select_p_select_nodeinfo_free",
	"select_p_select_nodeinfo_set_all",
	"select_p_select_nodeinfo_set",
	"select_p_select_nodeinfo_get",
	"select_p_select_jobinfo_alloc",
	"select_p_select_jobinfo_free",
	"select_p_select_jobinfo_set",
	"select_p_select_jobinfo_get",
	"select_p_select_jobinfo_copy",
	"select_p_select_jobinfo_pack",
	"select_p_select_jobinfo_unpack",
	"select_p_get_info_from_plugin",
	"select_p_reconfigure",
};

static int select_context_cnt = -1;
static int select_context_default = -1;

static slurm_select_ops_t *ops = NULL;
static plugin_context_t **select_context = NULL;
static pthread_mutex_t select_context_lock = PTHREAD_MUTEX_INITIALIZER;

typedef struct _plugin_args {
	char *plugin_type;
	char *default_plugin;
} _plugin_args_t;

typedef struct {
	int id;
	char *name;
} plugin_id_name;

const plugin_id_name plugin_ids[] = {
	{ SELECT_PLUGIN_LINEAR, "linear" },
	{ SELECT_PLUGIN_SERIAL, "serial" },
	{ SELECT_PLUGIN_CRAY_LINEAR, "cray_aries+linear" },
	{ SELECT_PLUGIN_CONS_TRES, "cons_tres" },
	{ SELECT_PLUGIN_CRAY_CONS_TRES, "cray_aries+cons_tres" },
};

extern char *select_plugin_id_to_string(int plugin_id)
{
	for (int i = 0; i < ARRAY_SIZE(plugin_ids); i++)
		if (plugin_id == plugin_ids[i].id)
			return plugin_ids[i].name;

	error("%s: unknown select plugin id: %d",
	      __func__, plugin_id);
	return NULL;
}

extern int select_string_to_plugin_id(const char *plugin)
{
	for (int i = 0; i < ARRAY_SIZE(plugin_ids); i++)
		if (xstrcasecmp(plugin, plugin_ids[i].name))
			return plugin_ids[i].id;

	error("%s: unknown select plugin: %s",
	      __func__, plugin);
	return 0;
}

static int _load_plugins(void *x, void *arg)
{
	char *plugin_name     = (char *)x;
	_plugin_args_t *pargs = (_plugin_args_t *)arg;

	select_context[select_context_cnt] =
		plugin_context_create(pargs->plugin_type, plugin_name,
				      (void **)&ops[select_context_cnt],
				      node_select_syms,
				      sizeof(node_select_syms));

	if (select_context[select_context_cnt]) {
		/* set the default */
		if (!xstrcmp(plugin_name, pargs->default_plugin))
			select_context_default = select_context_cnt;
		select_context_cnt++;
	}

	return 0;
}

extern int select_char2coord(char coord)
{
	if ((coord >= '0') && (coord <= '9'))
		return (coord - '0');
	if ((coord >= 'A') && (coord <= 'Z'))
		return ((coord - 'A') + 10);
	return -1;
}

/*
 * Initialize context for node selection plugin
 */
extern int select_g_init(bool only_default)
{
	int retval = SLURM_SUCCESS;
	int i, j, plugin_cnt;
	char *plugin_type = "select";
	List plugin_names = NULL;
	_plugin_args_t plugin_args = {0};

	slurm_mutex_lock( &select_context_lock );

	if ( select_context )
		goto done;

	if (working_cluster_rec) {
		/* just ignore warnings here */
	} else {
#ifdef HAVE_NATIVE_CRAY
		if (xstrcasecmp(slurm_conf.select_type, "select/cray_aries")) {
			error("%s is incompatible with a Cray/Aries system.",
			      slurm_conf.select_type);
			fatal("Use SelectType=select/cray_aries");
		}
#endif
	}

	select_context_cnt = 0;

	plugin_args.plugin_type    = plugin_type;
	plugin_args.default_plugin = slurm_conf.select_type;

	if (only_default) {
		plugin_names = list_create(xfree_ptr);
		list_append(plugin_names, xstrdup(slurm_conf.select_type));
	} else {
		plugin_names = plugin_get_plugins_of_type(plugin_type);
	}
	if (plugin_names && (plugin_cnt = list_count(plugin_names))) {
		ops = xcalloc(plugin_cnt, sizeof(slurm_select_ops_t));
		select_context = xcalloc(plugin_cnt,
					 sizeof(plugin_context_t *));
		list_for_each(plugin_names, _load_plugins, &plugin_args);
	}


	if (select_context_default == -1)
		fatal("Can't find plugin for %s", slurm_conf.select_type);

	/* Ensure that plugin_id is valid and unique */
	for (i=0; i<select_context_cnt; i++) {
		for (j=i+1; j<select_context_cnt; j++) {
			if (*(ops[i].plugin_id) !=
			    *(ops[j].plugin_id))
				continue;
			fatal("SelectPlugins: Duplicate plugin_id %u for "
			      "%s and %s",
			      *(ops[i].plugin_id),
			      select_context[i]->type,
			      select_context[j]->type);
		}
		if (*(ops[i].plugin_id) < 100) {
			fatal("SelectPlugins: Invalid plugin_id %u (<100) %s",
			      *(ops[i].plugin_id),
			      select_context[i]->type);
		}

	}
done:
	slurm_mutex_unlock( &select_context_lock );
	if (!working_cluster_rec) {
		if (select_running_linear_based()) {
			uint16_t cr_type = slurm_conf.select_type_param;
			if (cr_type & (CR_CPU | CR_CORE | CR_SOCKET)) {
				fatal("Invalid SelectTypeParameters for "
				      "%s: %s (%u), it can't contain "
				      "CR_(CPU|CORE|SOCKET).",
				      slurm_conf.select_type,
				      select_type_param_string(cr_type),
				      cr_type);
			}
		}
	}

	FREE_NULL_LIST(plugin_names);

	return retval;
}

extern int select_g_fini(void)
{
	int rc = SLURM_SUCCESS, i, j;

	slurm_mutex_lock(&select_context_lock);
	if (!select_context)
		goto fini;

	for (i=0; i<select_context_cnt; i++) {
		j = plugin_context_destroy(select_context[i]);
		if (j != SLURM_SUCCESS)
			rc = j;
	}
	xfree(ops);
	xfree(select_context);
	select_context_cnt = -1;

fini:	slurm_mutex_unlock(&select_context_lock);
	return rc;
}

/* Get this plugin's sequence number in Slurm's internal tables */
extern int select_get_plugin_id_pos(uint32_t plugin_id)
{
	int i;
	static bool cray_other_cons_tres = false;

	xassert(select_context_cnt >= 0);
again:
	for (i = 0; i < select_context_cnt; i++) {
		if (*(ops[i].plugin_id) == plugin_id)
			break;
	}
	if (i >= select_context_cnt) {
		/*
		 * Put on the extra Cray select plugins that do not get
		 * generated automatically.
		 */
		if (!cray_other_cons_tres &&
		    ((plugin_id == SELECT_PLUGIN_CRAY_CONS_TRES) ||
		     (plugin_id == SELECT_PLUGIN_CRAY_LINEAR))) {
			char *type = "select", *name = "select/cray_aries";
			uint16_t save_params = slurm_conf.select_type_param;
			uint16_t params;
			int cray_plugin_id;

			cray_other_cons_tres = true;

			if (plugin_id == SELECT_PLUGIN_CRAY_LINEAR) {
				params = save_params & ~CR_OTHER_CONS_TRES;
				cray_plugin_id = SELECT_PLUGIN_CRAY_CONS_TRES;
			} else {	/* SELECT_PLUGIN_CRAY_CONS_TRES */
				params = save_params | CR_OTHER_CONS_TRES;
				cray_plugin_id = SELECT_PLUGIN_CRAY_LINEAR;
			}

			for (i = 0; i < select_context_cnt; i++) {
				if (*(ops[i].plugin_id) == cray_plugin_id)
					break;
			}

			if (i >= select_context_cnt)
				goto end_it;	/* No match */

			slurm_mutex_lock(&select_context_lock);
			slurm_conf.select_type_param = params;
			plugin_context_destroy(select_context[i]);
			select_context[i] =
				plugin_context_create(type, name,
						      (void **)&ops[i],
						      node_select_syms,
						      sizeof(node_select_syms));
			slurm_conf.select_type_param = save_params;
			slurm_mutex_unlock(&select_context_lock);
			goto again;
		}

	end_it:
		return SLURM_ERROR;
	}
	return i;
}

/* Get the plugin ID number. Unique for each select plugin type */
extern int select_get_plugin_id(void)
{
	int plugin_pos;

	xassert(select_context_cnt >= 0);

	plugin_pos = working_cluster_rec ?
		working_cluster_rec->plugin_id_select : select_context_default;

	return *(ops[plugin_pos].plugin_id);
}

/* If the slurmctld is running a linear based select plugin return 1
 * else 0. */
extern int select_running_linear_based(void)
{
	int rc = 0;

	xassert(select_context_cnt >= 0);

	switch (*(ops[select_context_default].plugin_id)) {
	case SELECT_PLUGIN_LINEAR: // select/linear
	case SELECT_PLUGIN_CRAY_LINEAR: // select/cray -> linear
		rc = 1;
		break;
	default:
		rc = 0;
		break;
	}
	return rc;
}

/*
 * Convert SelectTypeParameter to equivalent string
 * NOTE: Not reentrant
 */
extern char *select_type_param_string(uint16_t select_type_param)
{
	static char select_str[1024];

	select_str[0] = '\0';
	if ((select_type_param & CR_CPU) &&
	    (select_type_param & CR_MEMORY))
		strcat(select_str, "CR_CPU_MEMORY");
	else if ((select_type_param & CR_CORE) &&
		 (select_type_param & CR_MEMORY))
		strcat(select_str, "CR_CORE_MEMORY");
	else if ((select_type_param & CR_SOCKET) &&
		 (select_type_param & CR_MEMORY))
		strcat(select_str, "CR_SOCKET_MEMORY");
	else if (select_type_param & CR_CPU)
		strcat(select_str, "CR_CPU");
	else if (select_type_param & CR_CORE)
		strcat(select_str, "CR_CORE");
	else if (select_type_param & CR_SOCKET)
		strcat(select_str, "CR_SOCKET");
	else if (select_type_param & CR_MEMORY)
		strcat(select_str, "CR_MEMORY");

	if (select_type_param & CR_OTHER_CONS_TRES) {
		if (select_str[0])
			strcat(select_str, ",");
		strcat(select_str, "OTHER_CONS_TRES");
	}
	if (select_type_param & CR_ONE_TASK_PER_CORE) {
		if (select_str[0])
			strcat(select_str, ",");
		strcat(select_str, "CR_ONE_TASK_PER_CORE");
	}
	if (select_type_param & CR_CORE_DEFAULT_DIST_BLOCK) {
		if (select_str[0])
			strcat(select_str, ",");
		strcat(select_str, "CR_CORE_DEFAULT_DIST_BLOCK");
	}
	if (select_type_param & CR_LLN) {
		if (select_str[0])
			strcat(select_str, ",");
		strcat(select_str, "CR_LLN");
	}
	if (select_type_param & CR_PACK_NODES) {
		if (select_str[0])
			strcat(select_str, ",");
		strcat(select_str, "CR_PACK_NODES");
	}
	if (select_str[0] == '\0')
		strcat(select_str, "NONE");

	return select_str;
}

/*
 * Save any global state information
 * IN dir_name - directory into which the data can be stored
 */
extern int select_g_state_save(char *dir_name)
{
	DEF_TIMERS;
	int rc;

	xassert(select_context_cnt >= 0);

	START_TIMER;
	rc = (*(ops[select_context_default].state_save))
		(dir_name);
	END_TIMER2(__func__);

	return rc;
}

/*
 * Initialize context for node selection plugin and
 * restore any global state information
 * IN dir_name - directory from which the data can be restored
 */
extern int select_g_state_restore(char *dir_name)
{
	xassert(select_context_cnt >= 0);

	return (*(ops[select_context_default].state_restore))
		(dir_name);
}

/*
 * Note the initialization of job records, issued upon restart of
 * slurmctld and used to synchronize any job state.
 */
extern int select_g_job_init(List job_list)
{
	xassert(select_context_cnt >= 0);

	return (*(ops[select_context_default].job_init))
		(job_list);
}

/*
 * Note re/initialization of node record data structure
 * IN node_ptr - current node data
 * IN node_count - number of node entries
 */
extern int select_g_node_init(void)
{
	xassert(select_context_cnt >= 0);

	return (*(ops[select_context_default].node_init))();
}

/*
 * Select the "best" nodes for given job from those available
 * IN/OUT job_ptr - pointer to job being considered for initiation,
 *                  set's start_time when job expected to start
 * IN/OUT bitmap - map of nodes being considered for allocation on input,
 *                 map of nodes actually to be assigned on output
 * IN min_nodes - minimum number of nodes to allocate to job
 * IN max_nodes - maximum number of nodes to allocate to job
 * IN req_nodes - requested (or desired) count of nodes
 * IN mode - SELECT_MODE_RUN_NOW: try to schedule job now
 *           SELECT_MODE_TEST_ONLY: test if job can ever run
 *           SELECT_MODE_WILL_RUN: determine when and where job can run
 * IN preemptee_candidates - List of pointers to jobs which can bee preempted
 * IN/OUT preemptee_job_list - Pointer to list of job pointers. These are the
 *		jobs to be preempted to initiate the pending job. Not set
 *		if mode=SELECT_MODE_TEST_ONLY or input pointer is NULL.
 *		Existing list is appended to.
 * IN resv_exc_ptr - Various TRES which the job can NOT use.
 * RET zero on success, EINVAL otherwise
 */
extern int select_g_job_test(job_record_t *job_ptr, bitstr_t *bitmap,
			     uint32_t min_nodes, uint32_t max_nodes,
			     uint32_t req_nodes, uint16_t mode,
			     List preemptee_candidates,
			     List *preemptee_job_list,
			     resv_exc_t *resv_exc_ptr)
{
	xassert(select_context_cnt >= 0);

	return (*(ops[select_context_default].job_test))
		(job_ptr, bitmap,
		 min_nodes, max_nodes,
		 req_nodes, mode,
		 preemptee_candidates, preemptee_job_list,
		 resv_exc_ptr);
}

/*
 * Note initiation of job is about to begin. Called immediately
 * after select_g_job_test(). Executed from slurmctld.
 * IN job_ptr - pointer to job being initiated
 */
extern int select_g_job_begin(job_record_t *job_ptr)
{
	xassert(select_context_cnt >= 0);

	return (*(ops[select_context_default].job_begin))
		(job_ptr);
}

/*
 * determine if job is ready to execute per the node select plugin
 * IN job_ptr - pointer to job being tested
 * RET: -2 fatal error, -1 try again, 1 if ready to execute,
 *	0 not ready to execute
 */
extern int select_g_job_ready(job_record_t *job_ptr)
{
	xassert(select_context_cnt >= 0);

	return (*(ops[select_context_default].job_ready))
		(job_ptr);
}

/*
 * Move the resource allocated to one job into that of another job.
 *	All resources are removed from "from_job_ptr" and moved into
 *	"to_job_ptr". Also see other_job_resized().
 * RET: 0 or an error code
 */
extern int select_g_job_expand(job_record_t *from_job_ptr,
			       job_record_t *to_job_ptr)
{
	xassert(select_context_cnt >= 0);

	return (*(ops[select_context_default].job_expand))
		(from_job_ptr, to_job_ptr);
}

/*
 * Modify internal data structures for a job that has changed size
 *	Only support jobs shrinking now.
 * RET: 0 or an error code
 */
extern int select_g_job_resized(job_record_t *job_ptr, node_record_t *node_ptr)
{
	xassert(select_context_cnt >= 0);

	return (*(ops[select_context_default].job_resized))
		(job_ptr, node_ptr);
}

/*
 * Note termination of job is starting. Executed from slurmctld.
 * IN job_ptr - pointer to job being terminated
 */
extern int select_g_job_fini(job_record_t *job_ptr)
{
	xassert(select_context_cnt >= 0);

	return (*(ops[select_context_default].job_fini))
		(job_ptr);
}

/*
 * Suspend a job. Executed from slurmctld.
 * IN job_ptr - pointer to job being suspended
 * IN indf_susp - set if job is being suspended indefinitely by user
 *                or admin, otherwise suspended for gang scheduling
 * RET SLURM_SUCCESS or error code
 */
extern int select_g_job_suspend(job_record_t *job_ptr, bool indf_susp)
{
	xassert(select_context_cnt >= 0);

	return (*(ops[select_context_default].job_suspend))
		(job_ptr, indf_susp);
}

/*
 * Resume a job. Executed from slurmctld.
 * IN job_ptr - pointer to job being resumed
 * IN indf_susp - set if job is being resumed from indefinite suspend by user
 *                or admin, otherwise resume from gang scheduling
 * RET SLURM_SUCCESS or error code
 */
extern int select_g_job_resume(job_record_t *job_ptr, bool indf_susp)
{
	xassert(select_context_cnt >= 0);

	return (*(ops[select_context_default].job_resume))
		(job_ptr, indf_susp);
}

/*
 * Select the "best" nodes for given job step from those available in
 * a job allocation.
 *
 * IN/OUT job_ptr - pointer to job already allocated and running in a
 *                  block where the step is to run.
 *                  set's start_time when job expected to start
 * OUT step_jobinfo - Fill in the resources to be used if not
 *                    full size of job.
 * IN node_count  - How many nodes we are looking for.
 * OUT avail_nodes - bitmap of available nodes according to the plugin
 *                  (not always set).
 * RET map of slurm nodes to be used for step, NULL on failure
 */
extern bitstr_t *select_g_step_pick_nodes(job_record_t *job_ptr,
					  dynamic_plugin_data_t *step_jobinfo,
					  uint32_t node_count,
					  bitstr_t **avail_nodes)
{
	xassert(select_context_cnt >= 0);

	xassert(step_jobinfo);

	return (*(ops[select_context_default].step_pick_nodes))
		(job_ptr, step_jobinfo->data, node_count, avail_nodes);
}

/*
 * Post pick_nodes operations for the step.
 * IN/OUT step_ptr - step pointer to operate on.
 */
extern int select_g_step_start(step_record_t *step_ptr)
{
	xassert(select_context_cnt >= 0);

	return (*(ops[select_context_default].step_start))
		(step_ptr);
}

/*
 * clear what happened in select_g_step_pick_nodes
 * IN/OUT step_ptr - Flush the resources from the job and step.
 * IN killing_step - if true then we are just starting to kill the step
 *                   if false, the step is completely terminated
 */
extern int select_g_step_finish(step_record_t *step_ptr, bool killing_step)
{
	xassert(select_context_cnt >= 0);

	return (*(ops[select_context_default].step_finish))
		(step_ptr, killing_step);
}

extern int select_g_select_nodeinfo_pack(dynamic_plugin_data_t *nodeinfo,
					 buf_t *buffer,
					 uint16_t protocol_version)
{
	void *data = NULL;
	uint32_t plugin_id;

	xassert(select_context_cnt >= 0);

	if (nodeinfo) {
		data = nodeinfo->data;
		plugin_id = nodeinfo->plugin_id;
	} else
		plugin_id = select_context_default;

	if (protocol_version >= SLURM_MIN_PROTOCOL_VERSION) {
		pack32(*(ops[plugin_id].plugin_id),
		       buffer);
	} else {
		error("%s: protocol_version %hu not supported", __func__,
		      protocol_version);
	}

	return (*(ops[plugin_id].
		  nodeinfo_pack))(data, buffer, protocol_version);
}

extern int select_g_select_nodeinfo_unpack(dynamic_plugin_data_t **nodeinfo,
					   buf_t *buffer,
					   uint16_t protocol_version)
{
	dynamic_plugin_data_t *nodeinfo_ptr = NULL;

	xassert(select_context_cnt >= 0);

	nodeinfo_ptr = xmalloc(sizeof(dynamic_plugin_data_t));
	*nodeinfo = nodeinfo_ptr;

	if (protocol_version >= SLURM_23_11_PROTOCOL_VERSION) {
		int i;
		uint32_t plugin_id;
		safe_unpack32(&plugin_id, buffer);
		if ((i = select_get_plugin_id_pos(plugin_id)) == SLURM_ERROR) {
			error("%s: select plugin %s not found", __func__,
			      select_plugin_id_to_string(plugin_id));
			goto unpack_error;
		} else {
			 nodeinfo_ptr->plugin_id = i;
		}
	} else if (protocol_version >= SLURM_MIN_PROTOCOL_VERSION) {
		int i;
		uint32_t plugin_id;
		safe_unpack32(&plugin_id, buffer);

		/* cons_res was removed; convert to cons_tres */
		if (plugin_id == SELECT_PLUGIN_CONS_RES) {
			plugin_id = SELECT_PLUGIN_CONS_TRES;
		} else if (plugin_id == SELECT_PLUGIN_CRAY_CONS_RES) {
			plugin_id = SELECT_PLUGIN_CRAY_CONS_TRES;
		}

		if ((i = select_get_plugin_id_pos(plugin_id)) == SLURM_ERROR) {
			error("%s: select plugin %s not found", __func__,
			      select_plugin_id_to_string(plugin_id));
			goto unpack_error;
		} else {
			 nodeinfo_ptr->plugin_id = i;
		}
	} else {
		nodeinfo_ptr->plugin_id = select_context_default;
		error("%s: protocol_version %hu not supported", __func__,
		      protocol_version);
		goto unpack_error;
	}

	if ((*(ops[nodeinfo_ptr->plugin_id].nodeinfo_unpack))
	   ((select_nodeinfo_t **)&nodeinfo_ptr->data, buffer,
	    protocol_version) != SLURM_SUCCESS)
		goto unpack_error;

	/*
	 * Free nodeinfo_ptr if it is different from local cluster as it is not
	 * relevant to this cluster.
	 */
	if ((nodeinfo_ptr->plugin_id != select_context_default) &&
	    running_in_slurmctld()) {
		select_g_select_nodeinfo_free(nodeinfo_ptr);
		*nodeinfo = select_g_select_nodeinfo_alloc();
	}

	return SLURM_SUCCESS;

unpack_error:
	select_g_select_nodeinfo_free(nodeinfo_ptr);
	*nodeinfo = NULL;
	error("%s: unpack error", __func__);
	return SLURM_ERROR;
}

extern dynamic_plugin_data_t *select_g_select_nodeinfo_alloc(void)
{
	dynamic_plugin_data_t *nodeinfo_ptr = NULL;
	uint32_t plugin_id;

	xassert(select_context_cnt >= 0);

	plugin_id = working_cluster_rec ?
		working_cluster_rec->plugin_id_select : select_context_default;

	nodeinfo_ptr = xmalloc(sizeof(dynamic_plugin_data_t));
	nodeinfo_ptr->plugin_id = plugin_id;
	nodeinfo_ptr->data = (*(ops[plugin_id].
				nodeinfo_alloc))();
	return nodeinfo_ptr;
}

extern int select_g_select_nodeinfo_free(dynamic_plugin_data_t *nodeinfo)
{
	int rc = SLURM_SUCCESS;

	xassert(select_context_cnt >= 0);

	if (nodeinfo) {
		if (nodeinfo->data)
			rc = (*(ops[nodeinfo->plugin_id].
				nodeinfo_free))(nodeinfo->data);
		xfree(nodeinfo);
	}
	return rc;
}

extern int select_g_select_nodeinfo_set_all(void)
{
	xassert(select_context_cnt >= 0);

	return (*(ops[select_context_default].nodeinfo_set_all))
		();
}

extern int select_g_select_nodeinfo_set(job_record_t *job_ptr)
{
	xassert(select_context_cnt >= 0);

	return (*(ops[select_context_default].nodeinfo_set))
		(job_ptr);
}

extern int select_g_select_nodeinfo_get(dynamic_plugin_data_t *nodeinfo,
					enum select_nodedata_type dinfo,
					enum node_states state,
					void *data)
{
	void *nodedata = NULL;
	uint32_t plugin_id;

	xassert(select_context_cnt >= 0);

	if (nodeinfo) {
		nodedata = nodeinfo->data;
		plugin_id = nodeinfo->plugin_id;
	} else
		plugin_id = select_context_default;

	return (*(ops[plugin_id].nodeinfo_get))
		(nodedata, dinfo, state, data);
}

extern dynamic_plugin_data_t *select_g_select_jobinfo_alloc(void)
{
	dynamic_plugin_data_t *jobinfo_ptr = NULL;
	uint32_t plugin_id;

	xassert(select_context_cnt >= 0);

	plugin_id = working_cluster_rec ?
		working_cluster_rec->plugin_id_select : select_context_default;

	jobinfo_ptr = xmalloc(sizeof(dynamic_plugin_data_t));
	jobinfo_ptr->plugin_id = plugin_id;
	jobinfo_ptr->data =  (*(ops[plugin_id].
				jobinfo_alloc))();
	return jobinfo_ptr;
}

/* free storage previously allocated for a select job credential
 * IN jobinfo  - the select job credential to be freed
 */
extern int select_g_select_jobinfo_free(dynamic_plugin_data_t *jobinfo)
{
	int rc = SLURM_SUCCESS;

	if (jobinfo) {
		if (jobinfo->data) {
			xassert(select_context_cnt >= 0);
			rc = (*(ops[jobinfo->plugin_id].
				jobinfo_free))(jobinfo->data);
		}
		xfree(jobinfo);
	}
	return rc;
}

extern int select_g_select_jobinfo_set(dynamic_plugin_data_t *jobinfo,
				       enum select_jobdata_type data_type,
				       void *data)
{
	void *jobdata = NULL;
	uint32_t plugin_id;

	xassert(select_context_cnt >= 0);

	if (jobinfo) {
		jobdata = jobinfo->data;
		plugin_id = jobinfo->plugin_id;
	} else
		plugin_id = select_context_default;

	return (*(ops[plugin_id].jobinfo_set))
		(jobdata, data_type, data);
}

/* get data from a select job credential
 * IN jobinfo  - updated select job credential
 * IN data_type - type of data to enter into job credential
 * IN/OUT data - the data to enter into job credential
 */
extern int select_g_select_jobinfo_get(dynamic_plugin_data_t *jobinfo,
				       enum select_jobdata_type data_type,
				       void *data)
{
	void *jobdata = NULL;
	uint32_t plugin_id;

	xassert(select_context_cnt >= 0);

	if (jobinfo) {
		jobdata = jobinfo->data;
		plugin_id = jobinfo->plugin_id;
	} else
		plugin_id = select_context_default;

	return (*(ops[plugin_id].jobinfo_get))
		(jobdata, data_type, data);
}

/* copy a select job credential
 * IN jobinfo - the select job credential to be copied
 * RET        - the copy or NULL on failure
 * NOTE: returned value must be freed using select_g_free_jobinfo
 */
extern dynamic_plugin_data_t *select_g_select_jobinfo_copy(
	dynamic_plugin_data_t *jobinfo)
{
	dynamic_plugin_data_t *jobinfo_ptr = NULL;
	xassert(select_context_cnt >= 0);

	jobinfo_ptr = xmalloc(sizeof(dynamic_plugin_data_t));
	if (jobinfo) {
		jobinfo_ptr->plugin_id = jobinfo->plugin_id;
		jobinfo_ptr->data = (*(ops[jobinfo->plugin_id].
				       jobinfo_copy))(jobinfo->data);
	} else
		jobinfo_ptr->plugin_id = select_context_default;

	return jobinfo_ptr;
}

/* pack a select job credential into a buffer in machine independent form
 * IN jobinfo  - the select job credential to be saved
 * OUT buffer  - buffer with select credential appended
 * RET         - slurm error code
 */
extern int select_g_select_jobinfo_pack(dynamic_plugin_data_t *jobinfo,
					buf_t *buffer,
					uint16_t protocol_version)
{
	void *data = NULL;
	uint32_t plugin_id;

	if (jobinfo) {
		data = jobinfo->data;
		plugin_id = jobinfo->plugin_id;
	} else
		plugin_id = select_context_default;

	/*
	 * Remove 2 versions after 23.02 -- 23.02 doesn't pack jobinfo anymore
	 * AND the select plugin isn't loaded in the slurmd in 23.11.
	 */
	if (!running_in_slurmctld() &&
	    (protocol_version <= SLURM_23_02_PROTOCOL_VERSION)) {
		pack32(plugin_id, buffer);
		return SLURM_SUCCESS;
	}

	xassert(select_context_cnt >= 0);

	if (protocol_version >= SLURM_MIN_PROTOCOL_VERSION) {
		pack32(*(ops[plugin_id].plugin_id), buffer);
	} else {
		error("%s: protocol_version %hu not supported", __func__,
		      protocol_version);
	}

	return (*(ops[plugin_id].jobinfo_pack))(data, buffer, protocol_version);
}

/* unpack a select job credential from a buffer
 * OUT jobinfo - the select job credential read
 * IN  buffer  - buffer with select credential read from current pointer loc
 * RET         - slurm error code
 * NOTE: returned value must be freed using select_g_free_jobinfo
 */
extern int select_g_select_jobinfo_unpack(dynamic_plugin_data_t **jobinfo,
					  buf_t *buffer,
					  uint16_t protocol_version)
{
	dynamic_plugin_data_t *jobinfo_ptr = NULL;

	/*
	 * Remove 2 versions after 23.02 -- 23.02 doesn't pack jobinfo anymore
	 * AND the select plugin isn't loaded in the slurmd in 23.11.
	 */
	if (!running_in_slurmctld() &&
	    (protocol_version <= SLURM_23_02_PROTOCOL_VERSION)) {
		uint32_t plugin_id;
		safe_unpack32(&plugin_id, buffer);
		/*
		 * srun will unpack this and then repack things later when
		 * sending to the slurmd. Instead of the context here we have
		 * the actual plugin id.
		 * This hack works for all systems that aren't cray_aries.
		 */
		select_context_default = plugin_id;
		*jobinfo = NULL;
		return SLURM_SUCCESS;
	}

	xassert(select_context_cnt >= 0);

	jobinfo_ptr = xmalloc(sizeof(dynamic_plugin_data_t));
	*jobinfo = jobinfo_ptr;

	if (protocol_version >= SLURM_23_11_PROTOCOL_VERSION) {
		int i;
		uint32_t plugin_id;
		safe_unpack32(&plugin_id, buffer);
		if ((i = select_get_plugin_id_pos(plugin_id)) == SLURM_ERROR) {
			error("%s: select plugin %s not found", __func__,
			      select_plugin_id_to_string(plugin_id));
			goto unpack_error;
		} else
			jobinfo_ptr->plugin_id = i;
	} else if (protocol_version >= SLURM_MIN_PROTOCOL_VERSION) {
		int i;
		uint32_t plugin_id;
		safe_unpack32(&plugin_id, buffer);

		/* cons_res was removed; convert to cons_tres */
		if (plugin_id == SELECT_PLUGIN_CONS_RES) {
			plugin_id = SELECT_PLUGIN_CONS_TRES;
		} else if (plugin_id == SELECT_PLUGIN_CRAY_CONS_RES) {
			plugin_id = SELECT_PLUGIN_CRAY_CONS_TRES;
		}

		if ((i = select_get_plugin_id_pos(plugin_id)) == SLURM_ERROR) {
			error("%s: select plugin %s not found", __func__,
			      select_plugin_id_to_string(plugin_id));
			goto unpack_error;
		} else
			jobinfo_ptr->plugin_id = i;
	} else {
		jobinfo_ptr->plugin_id = select_context_default;
		error("%s: protocol_version %hu not supported", __func__,
		      protocol_version);
		goto unpack_error;
	}

	if ((*(ops[jobinfo_ptr->plugin_id].jobinfo_unpack))
		((select_jobinfo_t **)&jobinfo_ptr->data, buffer,
		 protocol_version) != SLURM_SUCCESS)
		goto unpack_error;

	/*
	 * Free jobinfo_ptr if it is different from local cluster as it is not
	 * relevant to this cluster.
	 */
	if ((jobinfo_ptr->plugin_id != select_context_default) &&
	    running_in_slurmctld()) {
		select_g_select_jobinfo_free(jobinfo_ptr);
		*jobinfo = select_g_select_jobinfo_alloc();
	}

	return SLURM_SUCCESS;

unpack_error:
	select_g_select_jobinfo_free(jobinfo_ptr);
	*jobinfo = NULL;
	error("%s: unpack error", __func__);
	return SLURM_ERROR;
}

/*
 * Get select data from a plugin
 * IN dinfo     - type of data to get from the node record
 *                (see enum select_plugindata_info)
 * IN/OUT data  - the data to get from node record
 */
extern int select_g_get_info_from_plugin(enum select_plugindata_info dinfo,
					 job_record_t *job_ptr, void *data)
{
	xassert(select_context_cnt >= 0);

	return (*(ops[select_context_default].
		  get_info_from_plugin))(dinfo, job_ptr, data);
}

/*
 * Note reconfiguration or change in partition configuration
 */
extern int select_g_reconfigure (void)
{
	xassert(select_context_cnt >= 0);

	return (*(ops[select_context_default].reconfigure))();
}