src/plugins/mpi/mpich1_p4/mpich1_p4.c

/*****************************************************************************\
 **  mpi_mpich1_p4.c - Library routines for initiating jobs on with mpich1_p4
 *****************************************************************************
 *  Copyright (C) 2004-2007 The Regents of the University of California.
 *  Produced at Lawrence Livermore National Laboratory (cf, DISCLAIMER).
 *  Written by Morris Jette <jette1@llnl.gov>
 *  UCRL-CODE-226842.
 *  
 *  This file is part of SLURM, a resource management program.
 *  For details, see <http://www.llnl.gov/linux/slurm/>.
 *  
 *  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.
\*****************************************************************************/

#if     HAVE_CONFIG_H
#  include "config.h"
#endif

#include <fcntl.h>
#include <signal.h>
#include <stdlib.h>
#include <sys/poll.h>
#include <sys/types.h>

#include <slurm/slurm_errno.h>
#include "src/common/env.h"
#include "src/common/fd.h"
#include "src/common/hostlist.h"
#include "src/common/mpi.h"
#include "src/common/net.h"
#include "src/common/xmalloc.h"
#include "src/common/xstring.h"

/*
 * These variables are required by the generic plugin interface.  If they
 * are not found in the plugin, the plugin loader will ignore it.
 *
 * plugin_name - a string giving a human-readable description of the
 * plugin.  There is no maximum length, but the symbol must refer to
 * a valid string.
 *
 * plugin_type - a string suggesting the type of the plugin or its
 * applicability to a particular form of data or method of data handling.
 * If the low-level plugin API is used, the contents of this string are
 * unimportant and may be anything.  SLURM uses the higher-level plugin
 * interface which requires this string to be of the form
 *
 *      <application>/<method>
 *
 * where <application> is a description of the intended application of
 * the plugin (e.g., "switch" for SLURM switch) and <method> is a description 
 * of how this plugin satisfies that application.  SLURM will only load
 * a switch plugin if the plugin_type string has a prefix of "switch/".
 *
 * plugin_version - an unsigned 32-bit integer giving the version number
 * of the plugin.  If major and minor revisions are desired, the major
 * version number may be multiplied by a suitable magnitude constant such
 * as 100 or 1000.  Various SLURM versions will likely require a certain
 * minimum versions for their plugins as this API matures.
 */
const char plugin_name[]        = "mpi MPICH1_P4 plugin";
const char plugin_type[]        = "mpi/mpich1_p4";
const uint32_t plugin_version   = 100;

/* communication for master port info */ 
pthread_t p4_tid = (pthread_t) -1;
int p4_fd1 = -1, p4_fd2 = -1;

int p_mpi_hook_slurmstepd_task (const mpi_plugin_client_info_t *job,
				char ***env)
{
	char *nodelist, *task_cnt;

	nodelist = getenvp(*env, "SLURM_NODELIST");
	if (nodelist) {
		char *host_str = NULL, *tmp;
		hostlist_t hl = hostlist_create(nodelist);
		while ((tmp = hostlist_shift(hl))) {
			if (host_str)
				xstrcat(host_str, ",");
			xstrcat(host_str, tmp);
			free(tmp);
		}
		hostlist_destroy(hl);
		env_array_overwrite_fmt(env, "SLURM_MPICH_NODELIST", "%s", 
			host_str);
		xfree(host_str);
	}

	task_cnt = getenvp(*env, "SLURM_TASKS_PER_NODE");
	if (task_cnt) {
		char *task_str = NULL, tmp_str[32];
		int i=0, val, reps;
		while (task_cnt[i]) {
			if ((task_cnt[i] >= '0') && (task_cnt[i] <= '9'))
				val = atoi(&task_cnt[i]);
			else
				break;	/* bad parse */
			i++;
			while (task_cnt[i]
			&&     (task_cnt[i] != 'x') && (task_cnt[i] != ','))
				i++;
			if (task_cnt[i] == 'x') {
				i++;
				reps = atoi(&task_cnt[i]);
				while (task_cnt[i] && (task_cnt[i] != ','))
					i++;
			} else
				reps = 1;
			if (task_cnt[i] == ',')
				i++;
			while (reps) {
				if (task_str)
					xstrcat(task_str, ",");
				snprintf(tmp_str, sizeof(tmp_str), "%d", val);
				xstrcat(task_str, tmp_str);
				reps--;
			}
		}
		env_array_overwrite_fmt(env, "SLURM_MPICH_TASKS", "%s",
			task_str);
		xfree(task_str);
	}

	return SLURM_SUCCESS;
}

static void *mpich1_thr(void *arg)
{
	int cc, flags;
	int new_port, new_fd;
	struct pollfd ufds;
	struct sockaddr cli_addr;
	socklen_t cli_len;
	char in_buf[128];

	debug("waiting for p4 communication");
	if ((flags = fcntl(p4_fd1, F_GETFL)) < 0) {
		error("mpich_p4: fcntl: %m");
		return NULL;
	}
	if (fcntl(p4_fd1, F_SETFL, flags | O_NONBLOCK) < 0) {
		error("mpich_p4: fcntl: %m");
		return NULL;
	}
	ufds.fd = p4_fd1;
	ufds.events = POLLIN | POLLERR | POLLHUP | POLLNVAL;
	while (1) {
		if (p4_tid == (pthread_t) -1)
			return NULL;
		cc = read(p4_fd1, &new_port, sizeof(new_port));
		if (cc >= 0)
			break;
		if (errno != EAGAIN) {
			error("mpich_p4: read/1: %m");
			return NULL;
		}
		cc = poll(&ufds, 1, 10000);
		if (cc <= 0) {
			error("mpich_p4: poll/1: %m");
			return NULL;
		}
	}
	if (cc != sizeof(new_port)) {
		error("mpich_p4: read/1 %d bytes", cc);
		return NULL;
	}
	debug("mpich_p4 read/1 port %d", new_port);

	/* send this port number to other tasks on demand */
	while (1) {
		if (p4_tid == (pthread_t) -1)
			return NULL;
		new_fd = accept(p4_fd2, &cli_addr, &cli_len);
		if (new_fd < 0)
			continue;
		cc = read(new_fd, in_buf, sizeof(in_buf));
		if (cc > 0)
			debug("mpich_p4 read/2 port: %s", in_buf);
		cc = write(new_fd, &new_port, sizeof(new_port));
		if (cc < sizeof(new_port))
			error("mpich_p4: write2: %m");
		close(new_fd);
	}
	return NULL;
}

mpi_plugin_client_state_t *
p_mpi_hook_client_prelaunch(mpi_plugin_client_info_t *job, char ***env)
{
	struct sockaddr_in sin;
	pthread_attr_t attr;
	socklen_t len = sizeof(sin);
	short port1, port2;

	debug("Using mpi/mpich1_p4");
	if ((p4_fd1 = socket(PF_INET, SOCK_DGRAM, 0)) < 0) {
		error("socket: %m");
		return NULL;
	}
	memset(&sin, 0, sizeof(sin));
	sin.sin_family = PF_INET;
	if (bind(p4_fd1, (struct sockaddr *) &sin, len) < 0) {
		error("bind: %m");
		return NULL;
	}
	if (getsockname(p4_fd1, (struct sockaddr *) &sin, &len) < 0) {
		error("getsockname: %m");
		return NULL;
	}
	port1 = ntohs(sin.sin_port);

	if ((p4_fd2 = socket(PF_INET, SOCK_STREAM, 0)) < 0) {
		error("socket: %m");
		return NULL;
	}
	memset(&sin, 0, sizeof(sin));
	sin.sin_family = PF_INET;
	sin.sin_addr.s_addr = htonl(INADDR_ANY);
	if (bind(p4_fd2, (struct sockaddr *) &sin, len) < 0) {
		error("bind: %m");
		return NULL;
	}
	if (listen(p4_fd2, 64) < 0)
		error("listen: %m");
	if (getsockname(p4_fd2, (struct sockaddr *) &sin, &len) < 0) {
		error("getsockname: %m");
		return NULL;
	}
	port2 = ntohs(sin.sin_port);

	/* Process messages in a separate thread */
	slurm_attr_init(&attr);
	pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED);
	if (pthread_create(&p4_tid, &attr, &mpich1_thr, NULL)) {
		error("pthread_create: %m");
		slurm_attr_destroy(&attr);
		return NULL;
	}
	slurm_attr_destroy(&attr);
	env_array_overwrite_fmt(env, "SLURM_MPICH_PORT1", "%hu", port1);
	env_array_overwrite_fmt(env, "SLURM_MPICH_PORT2", "%hu", port2);
	debug("mpich_p4 plugin listening on fd=%d,%d ports=%d,%d", 
		p4_fd1, p4_fd2, port1, port2);

	/* only return NULL on error */
	return (void *)0xdeadbeef;
}

int p_mpi_hook_client_single_task_per_node()
{
	return true;
}

int p_mpi_hook_client_fini(mpi_plugin_client_state_t *state)
{
	if (p4_tid != (pthread_t)-1) {
		pthread_cancel(p4_tid);
		pthread_join(p4_tid, NULL);
		p4_tid = (pthread_t) -1;
	}
	return SLURM_SUCCESS;
}