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pyxis_slurmstepd.c
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pyxis_slurmstepd.c
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/*
* Copyright (c) 2019-2020, NVIDIA CORPORATION. All rights reserved.
*/
#include <linux/limits.h>
#include <sys/mman.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <errno.h>
#include <fcntl.h>
#include <ftw.h>
#include <paths.h>
#include <pthread.h>
#include <sched.h>
#include <stdbool.h>
#include <stddef.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <slurm/spank.h>
#include "pyxis_slurmstepd.h"
#include "common.h"
#include "config.h"
#include "args.h"
#include "seccomp_filter.h"
#include "enroot.h"
struct container {
char *name;
char *save_path;
bool reuse_rootfs;
bool reuse_ns;
bool temporary;
int userns_fd;
int mntns_fd;
int cgroupns_fd;
int cwd_fd;
};
struct job_info {
uid_t uid;
gid_t gid;
uint32_t jobid;
uint32_t stepid;
uint32_t local_task_count;
char **environ;
char cwd[PATH_MAX];
};
struct shared_memory {
pthread_mutex_t mutex;
uint32_t init_tasks;
uint32_t started_tasks;
pid_t pid;
pid_t ns_pid;
};
struct plugin_context {
bool enabled;
int log_fd;
struct plugin_config config;
struct plugin_args *args;
struct job_info job;
struct container container;
int user_init_rv;
struct shared_memory *shm;
};
static struct plugin_context context = {
.enabled = false,
.log_fd = -1,
.config = { .runtime_path = { 0 } },
.args = NULL,
.job = { .uid = -1, .gid = -1, .jobid = 0, .stepid = 0, .environ = NULL, .cwd = { 0 } },
.container = { .name = NULL, .save_path = NULL, .reuse_rootfs = false, .reuse_ns = false, .temporary = false, .userns_fd = -1, .mntns_fd = -1, .cgroupns_fd = -1, .cwd_fd = -1 },
.user_init_rv = 0,
};
static bool pyxis_remap_root(void)
{
return context.args->remap_root == 1 || (context.args->remap_root == -1 && context.config.remap_root == true);
}
static bool pyxis_execute_entrypoint(void)
{
return context.args->entrypoint == 1 || (context.args->entrypoint == -1 && context.config.execute_entrypoint == true);
}
int pyxis_slurmstepd_init(spank_t sp, int ac, char **av)
{
int ret;
ret = pyxis_config_parse(&context.config, ac, av);
if (ret < 0) {
slurm_error("pyxis: failed to parse configuration");
return (-1);
}
context.args = pyxis_args_register(sp);
if (context.args == NULL) {
slurm_error("pyxis: failed to register arguments");
return (-1);
}
return (0);
}
static int job_get_info(spank_t sp, struct job_info *job)
{
spank_err_t rc;
int rv = -1;
rc = spank_get_item(sp, S_JOB_UID, &job->uid);
if (rc != ESPANK_SUCCESS) {
slurm_error("pyxis: couldn't get job uid: %s", spank_strerror(rc));
goto fail;
}
rc = spank_get_item(sp, S_JOB_GID, &job->gid);
if (rc != ESPANK_SUCCESS) {
slurm_error("pyxis: couldn't get job gid: %s", spank_strerror(rc));
goto fail;
}
rc = spank_get_item(sp, S_JOB_ID, &job->jobid);
if (rc != ESPANK_SUCCESS) {
slurm_error("pyxis: couldn't get job ID: %s", spank_strerror(rc));
goto fail;
}
rc = spank_get_item(sp, S_JOB_STEPID, &job->stepid);
if (rc != ESPANK_SUCCESS) {
slurm_error("pyxis: couldn't get job step ID: %s", spank_strerror(rc));
goto fail;
}
rc = spank_get_item(sp, S_JOB_LOCAL_TASK_COUNT, &job->local_task_count);
if (rc != ESPANK_SUCCESS) {
slurm_error("pyxis: couldn't get job local task count: %s", spank_strerror(rc));
goto fail;
}
/* This should probably be added to the API as a spank_item */
rc = spank_getenv(sp, "PWD", job->cwd, sizeof(job->cwd));
if (rc != ESPANK_SUCCESS)
slurm_info("pyxis: couldn't get job cwd path: %s", spank_strerror(rc));
rv = 0;
fail:
return (rv);
}
static int job_get_env(spank_t sp, struct job_info *job)
{
spank_err_t rc;
char **spank_environ = NULL;
size_t environ_len = 0;
int rv = -1;
rc = spank_get_item(sp, S_JOB_ENV, &spank_environ);
if (rc != ESPANK_SUCCESS) {
slurm_error("pyxis: couldn't get job environment: %s", spank_strerror(rc));
goto fail;
}
if (job->environ != NULL) {
for (int i = 0; job->environ[i] != NULL; ++i)
free(job->environ[i]);
free(job->environ);
job->environ = NULL;
}
/* We need to make a copy of the environment returned by the SPANK API. */
for (size_t i = 0; spank_environ[i] != NULL; ++i)
environ_len += 1;
job->environ = malloc((environ_len + 1) * sizeof(char*));
if (job->environ == NULL)
goto fail;
job->environ[environ_len] = NULL;
for (size_t i = 0; i < environ_len; ++i) {
job->environ[i] = strdup(spank_environ[i]);
if (job->environ[i] == NULL)
goto fail;
}
rv = 0;
fail:
return (rv);
}
/* As root, create the per-user runtime directory where temporary squashfs files are stored. */
static int enroot_create_user_runtime_dir(void)
{
int ret;
char path[PATH_MAX];
ret = snprintf(path, sizeof(path), "%s/%u", context.config.runtime_path, context.job.uid);
if (ret < 0 || ret >= sizeof(path))
return (-1);
ret = mkdir(path, 0700);
if (ret < 0 && errno != EEXIST) {
slurm_error("pyxis: couldn't mkdir %s: %s", path, strerror(errno));
return (-1);
}
if (ret < 0 && errno == EEXIST)
return (0);
ret = chown(path, context.job.uid, context.job.gid);
if (ret < 0) {
slurm_error("pyxis: couldn't chown %s: %s", path, strerror(errno));
rmdir(path);
return (-1);
}
return (0);
}
int pyxis_slurmstepd_post_opt(spank_t sp, int ac, char **av)
{
int ret;
if (!pyxis_args_enabled())
return (0);
context.enabled = true;
ret = job_get_info(sp, &context.job);
if (ret < 0)
return (-1);
ret = enroot_create_user_runtime_dir();
if (ret < 0)
return (-1);
return (0);
}
static int enroot_new_log(void)
{
xclose(context.log_fd);
/* We can use CLOEXEC here since we dup2(2) this file descriptor when needed. */
context.log_fd = pyxis_memfd_create("enroot-log", MFD_CLOEXEC);
if (context.log_fd < 0)
slurm_info("pyxis: couldn't create in-memory log file: %s", strerror(errno));
return (context.log_fd);
}
/*
* List of environment variables that should not be passed from the Slurm job to enroot.
*/
#define PYXIS_ENV_ENTRY(s) { s, sizeof(s) - 1 }
static const struct {
const char *name;
size_t len;
} enroot_deny_env[] = {
PYXIS_ENV_ENTRY("PATH="),
PYXIS_ENV_ENTRY("LD_LIBRARY_PATH="),
PYXIS_ENV_ENTRY("LD_PRELOAD="),
PYXIS_ENV_ENTRY("SLURM_PROCID="),
PYXIS_ENV_ENTRY("SLURM_LOCALID="),
PYXIS_ENV_ENTRY("SLURM_TASK_PID="),
PYXIS_ENV_ENTRY("PMIX_RANK="),
PYXIS_ENV_ENTRY("PMI_FD="),
PYXIS_ENV_ENTRY("ENROOT_LIBRARY_PATH="),
PYXIS_ENV_ENTRY("ENROOT_SYSCONF_PATH="),
PYXIS_ENV_ENTRY("ENROOT_RUNTIME_PATH="),
PYXIS_ENV_ENTRY("ENROOT_CACHE_PATH="),
PYXIS_ENV_ENTRY("ENROOT_DATA_PATH="),
PYXIS_ENV_ENTRY("ENROOT_TEMP_PATH="),
PYXIS_ENV_ENTRY("ENROOT_ZSTD_OPTIONS="),
PYXIS_ENV_ENTRY("ENROOT_TRANSFER_RETRIES="),
PYXIS_ENV_ENTRY("ENROOT_CONNECT_TIMEOUT="),
PYXIS_ENV_ENTRY("ENROOT_TRANSFER_TIMEOUT="),
PYXIS_ENV_ENTRY("ENROOT_MAX_CONNECTIONS="),
PYXIS_ENV_ENTRY("ENROOT_ALLOW_HTTP="),
{ NULL, 0 }
};
#undef PYXIS_ENV_ENTRY
static int try_import_env(char *string)
{
for (int i = 0; enroot_deny_env[i].name != NULL; ++i) {
if (strncmp(string, enroot_deny_env[i].name, enroot_deny_env[i].len) == 0)
return (0);
}
if (putenv(string) < 0)
return (-1);
return (0);
}
static int enroot_import_job_env(char **env)
{
if (env == NULL)
return (-1);
/* Import all allowed environment variables from the job */
for (int i = 0; env[i]; ++i) {
if (try_import_env(env[i]) < 0)
return (-1);
}
return (0);
}
static int enroot_set_env(void)
{
if (enroot_import_job_env(context.job.environ) < 0)
return (-1);
if (context.args->mount_home == 0) {
if (setenv("ENROOT_MOUNT_HOME", "n", 1) < 0)
return (-1);
} else if (context.args->mount_home == 1) {
if (setenv("ENROOT_MOUNT_HOME", "y", 1) < 0)
return (-1);
} else {
/* If mount_home was not set by the user, we rely on the setting specified in the enroot config. */
}
if (pyxis_remap_root()) {
if (setenv("ENROOT_REMAP_ROOT", "y", 1) < 0)
return (-1);
} else {
if (setenv("ENROOT_REMAP_ROOT", "n", 1) < 0)
return (-1);
}
if (context.args->writable == 0) {
if (setenv("ENROOT_ROOTFS_WRITABLE", "n", 1) < 0)
return (-1);
} else if (context.args->writable == 1) {
if (setenv("ENROOT_ROOTFS_WRITABLE", "y", 1) < 0)
return (-1);
} else {
/* If writable/readonly was not set by the user, we rely on the setting specified in the enroot config. */
}
return (0);
}
static pid_t enroot_exec_ctx(char *const argv[])
{
return enroot_exec(context.job.uid, context.job.gid, enroot_new_log(), enroot_set_env, argv);
}
static int enroot_exec_wait_ctx(char *const argv[])
{
return enroot_exec_wait(context.job.uid, context.job.gid, enroot_new_log(), enroot_set_env, argv);
}
static FILE *enroot_exec_output_ctx(char *const argv[])
{
return enroot_exec_output(context.job.uid, context.job.gid, enroot_set_env, argv);
}
static void enroot_print_log_ctx(void)
{
if (context.log_fd >= 0) {
enroot_print_log(context.log_fd);
xclose(context.log_fd);
context.log_fd = -1;
}
}
/*
* Returns -1 if an error occurs.
* Returns 0 and set *pid==-1 if container doesn't exist.
* Returns 0 and set *pid==0 if container exists but is not running.
* Returns 0 and set *pid>0 (the container PID) if the container exists and is running.
*/
static int enroot_container_get(const char *name, pid_t *pid)
{
FILE *fp;
char *line;
char *ctr_name, *ctr_pid, *saveptr;
unsigned long n;
int rv = -1;
if (name == NULL || strlen(name) == 0 || pid == NULL)
return (-1);
*pid = -1;
fp = enroot_exec_output_ctx((char *const[]){ "enroot", "list", "-f", NULL });
if (fp == NULL) {
slurm_error("pyxis: couldn't get list of existing container filesystems");
return (-1);
}
/* Skip headers line */
line = get_line_from_file(fp);
if (line == NULL) {
slurm_error("pyxis: \"enroot list -f\" did not produce any usable output");
goto fail;
}
while ((line = get_line_from_file(fp)) != NULL) {
ctr_name = strtok_r(line, " ", &saveptr);
if (ctr_name == NULL || *ctr_name == '\0')
goto fail;
if (strcmp(name, ctr_name) == 0) {
ctr_pid = strtok_r(NULL, " ", &saveptr);
if (ctr_pid == NULL || *ctr_pid == '\0') {
*pid = 0;
} else {
errno = 0;
n = strtoul(ctr_pid, NULL, 10);
if (errno != 0 || n != (pid_t)n)
goto fail;
*pid = (pid_t)n;
}
break;
}
free(line);
line = NULL;
}
rv = 0;
fail:
free(line);
if (fp) fclose(fp);
return (rv);
}
static int read_proc_environ(pid_t pid, char **result, size_t *size)
{
int ret;
char path[PATH_MAX];
int fd = -1;
char *buf = NULL;
size_t len = 0, capacity = 1024;
char *new_buf = NULL;
int rv = -1;
ret = snprintf(path, sizeof(path), "/proc/%d/environ", pid);
if (ret < 0 || ret >= sizeof(path))
goto fail;
fd = open(path, O_RDONLY);
if (fd < 0)
goto fail;
buf = malloc(capacity + 1);
if (buf == NULL)
goto fail;
while ((ret = read(fd, buf + len, capacity - len)) > 0) {
len += ret;
if (capacity - len == 0) {
/* Grow buffer. */
capacity *= 2;
new_buf = realloc(buf, capacity + 1);
if (new_buf == NULL)
goto fail;
buf = new_buf;
}
}
if (ret < 0)
goto fail;
/* From man 5 proc, there might not be a null byte at the end. */
if (len > 0 && buf[len - 1] != '\0') {
buf[len] = '\0';
len += 1;
}
*result = buf;
*size = len;
rv = 0;
fail:
xclose(fd);
if (rv < 0)
free(buf);
return (rv);
}
static int spank_import_container_env(spank_t sp, pid_t pid)
{
int ret;
char *proc_environ = NULL;
size_t size;
spank_err_t rc;
int rv = -1;
ret = read_proc_environ(pid, &proc_environ, &size);
if (ret < 0) {
slurm_error("pyxis: couldn't read /proc/%d/environ", pid);
goto fail;
}
for (size_t i = 0; i < size;) {
char *key, *value;
value = proc_environ + i;
key = strsep(&value, "=");
rc = spank_setenv(sp, key, value, 1);
if (rc != ESPANK_SUCCESS) {
slurm_error("pyxis: failed to set %s: %s", key, spank_strerror(rc));
goto fail;
}
i += strlen(key) + 1 + strlen(value) + 1;
}
rv = 0;
fail:
free(proc_environ);
return (rv);
}
static int enroot_container_create(void)
{
int ret;
char squashfs_path[PATH_MAX];
char *enroot_uri = NULL;
bool should_delete_squashfs = false;
int rv = -1;
if (strspn(context.args->image, "./") > 0) {
/* Assume `image` is a path to a squashfs file. */
if (strnlen(context.args->image, sizeof(squashfs_path)) >= sizeof(squashfs_path))
goto fail;
strncpy(squashfs_path, context.args->image, sizeof(squashfs_path) - 1);
squashfs_path[sizeof(squashfs_path) - 1] = '\0';
} else {
/* Assume `image` is an enroot URI for a docker image. */
ret = xasprintf(&enroot_uri, "docker://%s", context.args->image);
if (ret < 0)
goto fail;
ret = snprintf(squashfs_path, sizeof(squashfs_path), "%s/%u/%u.%u.squashfs", context.config.runtime_path, context.job.uid, context.job.jobid, context.job.stepid);
if (ret < 0 || ret >= sizeof(squashfs_path))
goto fail;
should_delete_squashfs = true;
slurm_spank_log("pyxis: importing docker image ...");
ret = enroot_exec_wait_ctx((char *const[]){ "enroot", "import", "--output", squashfs_path, enroot_uri, NULL });
if (ret < 0) {
slurm_error("pyxis: failed to import docker image");
enroot_print_log_ctx();
goto fail;
}
}
slurm_info("pyxis: creating container filesystem ...");
ret = enroot_exec_wait_ctx((char *const[]){ "enroot", "create", "--name", context.container.name, squashfs_path, NULL });
if (ret < 0) {
slurm_error("pyxis: failed to create container filesystem");
enroot_print_log_ctx();
goto fail;
}
rv = 0;
fail:
free(enroot_uri);
if (should_delete_squashfs && *squashfs_path != '\0') {
ret = unlink(squashfs_path);
if (ret < 0)
slurm_info("pyxis: could not remove squashfs: %s", strerror(errno));
}
return (rv);
}
static int container_get_namespaces(pid_t pid, struct container *container)
{
int ret;
char path[PATH_MAX];
int rv = -1;
ret = snprintf(path, sizeof(path), "/proc/%d/ns/user", pid);
if (ret < 0 || ret >= sizeof(path))
goto fail;
container->userns_fd = open(path, O_RDONLY | O_CLOEXEC);
if (container->userns_fd < 0) {
slurm_error("pyxis: unable to open user namespace file: %s", strerror(errno));
goto fail;
}
ret = snprintf(path, sizeof(path), "/proc/%d/ns/mnt", pid);
if (ret < 0 || ret >= sizeof(path))
goto fail;
container->mntns_fd = open(path, O_RDONLY | O_CLOEXEC);
if (container->mntns_fd < 0) {
slurm_error("pyxis: unable to open mount namespace file: %s", strerror(errno));
goto fail;
}
ret = snprintf(path, sizeof(path), "/proc/%d/ns/cgroup", pid);
if (ret < 0 || ret >= sizeof(path))
goto fail;
container->cgroupns_fd = open(path, O_RDONLY | O_CLOEXEC);
/* Skip cgroup namespace if not supported */
if (container->cgroupns_fd < 0 && errno != ENOENT) {
slurm_error("pyxis: unable to open cgroup namespace file: %s", strerror(errno));
goto fail;
}
rv = 0;
fail:
return (rv);
}
static int container_get_cwd(pid_t pid, struct container *container)
{
int ret;
char path[PATH_MAX];
ret = snprintf(path, sizeof(path), "/proc/%d/cwd", pid);
if (ret < 0 || ret >= sizeof(path))
return (-1);
container->cwd_fd = open(path, O_RDONLY | O_CLOEXEC);
if (container->cwd_fd < 0) {
slurm_error("pyxis: couldn't open cwd fd");
return (-1);
}
return (0);
}
static int enroot_create_start_config(char (*path)[PATH_MAX])
{
int ret;
int fd = -1;
FILE *f = NULL;
char template[] = "/tmp/.enroot_config_XXXXXX";
char *line = NULL;
int rv = -1;
fd = mkstemp(template);
if (fd < 0)
goto fail;
f = fdopen(fd, "a+");
if (f == NULL)
goto fail;
if (context.args->mounts_len > 0) {
ret = fprintf(f, "mounts() {\n");
if (ret < 0)
goto fail;
/* mount entries */
for (int i = 0; i < context.args->mounts_len; ++i) {
ret = fprintf(f, "\techo \"%s\"\n", context.args->mounts[i]);
if (ret < 0)
goto fail;
}
ret = fprintf(f, "}\n");
if (ret < 0)
goto fail;
}
if (!pyxis_execute_entrypoint()) {
ret = fprintf(f, "hooks() {\n");
if (ret < 0)
goto fail;
/*
* /etc/rc.local will be sourced by /etc/rc.
* We call 'exec' from there and do not return control to /etc/rc.
*/
ret = fprintf(f, "\techo 'exec \"$@\"' > ${ENROOT_ROOTFS}/etc/rc.local\n");
if (ret < 0)
goto fail;
ret = fprintf(f, "}\n");
if (ret < 0)
goto fail;
}
/* print contents */
if (fseek(f, 0, SEEK_SET) == 0) {
slurm_verbose("pyxis: enroot start configuration script:");
while ((line = get_line_from_file(f)) != NULL) {
slurm_verbose("pyxis: %s", line);
free(line);
}
}
if (memccpy(*path, template, '\0', sizeof(*path)) == NULL)
goto fail;
rv = 0;
fail:
if (f != NULL)
fclose(f);
xclose(fd);
return (rv);
}
static pid_t enroot_container_start(void)
{
int ret;
char conf_file[PATH_MAX] = { 0 };
pid_t pid = -1;
int status;
pid_t rv = -1;
slurm_info("pyxis: starting container ...");
ret = enroot_create_start_config(&conf_file);
if (ret < 0) {
slurm_error("pyxis: couldn't create enroot start configuration script");
goto fail;
}
/*
* The plugin starts the container as a subprocess and acquires handles on the
* container's namespaces. We must do this after the container runtime has called
* unshare(2) and pivot_root(2). To synchronize the plugin and the container, the
* shell inside the container sends itself SIGSTOP through the command "kill -STOP
* $$" and the plugin waits for the container to be stopped by calling waitpid(2)
* with the WUNTRACED option.
* This requires a shell inside the container, but we could do the same with a
* small static C program bind-mounted inside the container.
*/
pid = enroot_exec_ctx((char *const[]){ "enroot", "start", "--conf", conf_file, context.container.name, "sh", "-c",
"kill -STOP $$ ; exit 0", NULL });
if (pid < 0) {
slurm_error("pyxis: failed to start container");
goto fail;
}
/* Wait for the child to terminate or stop itself (with WUNTRACED). */
ret = waitpid(pid, &status, WUNTRACED);
if (ret < 0) {
slurm_error("pyxis: container start error: %s", strerror(errno));
goto fail;
}
if (WIFEXITED(status) && (ret = WEXITSTATUS(status)) != 0) {
slurm_error("pyxis: container start failed with error code: %d", ret);
goto fail;
}
if (!WIFSTOPPED(status)) {
slurm_error("pyxis: container exited too soon");
goto fail;
}
rv = pid;
fail:
if (rv == -1)
enroot_print_log_ctx();
if (conf_file[0] != '\0')
unlink(conf_file);
return (rv);
}
static int enroot_container_stop(pid_t pid)
{
int ret;
if (pid <= 0)
return (-1);
ret = kill(pid, SIGCONT);
if (ret < 0) {
slurm_error("pyxis: couldn't send SIGCONT to container process: %s", strerror(errno));
return (-1);
}
return (0);
}
static struct shared_memory *shm_init(void)
{
struct shared_memory *shm = NULL;
pthread_mutexattr_t mutex_attr;
int ret;
shm = mmap(0, sizeof(*shm), PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, -1, 0);
if (shm == MAP_FAILED) {
shm = NULL;
goto fail;
}
ret = pthread_mutexattr_init(&mutex_attr);
if (ret < 0)
goto fail;
ret = pthread_mutexattr_setpshared(&mutex_attr, PTHREAD_PROCESS_SHARED);
if (ret < 0)
goto fail;
ret = pthread_mutex_init(&shm->mutex, &mutex_attr);
if (ret < 0)
goto fail;
shm->init_tasks = 0;
shm->started_tasks = 0;
shm->pid = -1;
shm->ns_pid = -1;
return shm;
fail:
if (shm != NULL)
munmap(shm, sizeof(*shm));
return (NULL);
}
static int shm_destroy(struct shared_memory *shm)
{
int ret;
if (shm == NULL)
return (0);
ret = pthread_mutex_destroy(&shm->mutex);
if (ret < 0)
return (-1);
ret = munmap(shm, sizeof(*shm));
if (ret < 0)
return (-1);
return (0);
}
int slurm_spank_user_init(spank_t sp, int ac, char **av)
{
int ret;
spank_err_t rc;
int spank_argc = 0;
char **spank_argv = NULL;
char *container_name = NULL;
pid_t pid;
int rv = -1;
if (!context.enabled)
return (0);
context.shm = shm_init();
if (context.shm == NULL)
goto fail;
ret = job_get_env(sp, &context.job);
if (ret < 0)
goto fail;
if (context.job.stepid == SLURM_BATCH_SCRIPT) {
rc = spank_get_item(sp, S_JOB_ARGV, &spank_argc, &spank_argv);
if (rc != ESPANK_SUCCESS) {
slurm_error("pyxis: couldn't get job argv: %s", spank_strerror(rc));
goto fail;
}
if (spank_argc == 0) {
slurm_error("pyxis: couldn't get sbatch script: argc == 0");
goto fail;
}
/* Mount the sbatch script (from the Slurmd spool dir) inside the container */
ret = add_mount(spank_argv[0], spank_argv[0],
"x-create=file,bind,ro,nosuid,nodev,private");
if (ret < 0) {
slurm_error("pyxis: couldn't add bind mount for sbatch script");
goto fail;
}
}
if (context.args->container_name != NULL) {
if (context.config.container_scope == SCOPE_JOB)
ret = xasprintf(&container_name, "pyxis_%u_%s", context.job.jobid, context.args->container_name);
else
ret = xasprintf(&container_name, "pyxis_%s", context.args->container_name);
if (ret < 0)
goto fail;
ret = enroot_container_get(container_name, &pid);
if (ret < 0) {
slurm_error("pyxis: couldn't get list of containers");
goto fail;
}
if (pid > 0) {
slurm_info("pyxis: reusing existing container namespaces");
context.shm->ns_pid = pid;
context.container.reuse_ns = true;
context.container.reuse_rootfs = true;
} else if (pid == 0) {
slurm_info("pyxis: reusing existing container filesystem");
context.container.reuse_rootfs = true;
} else if (context.args->image == NULL) {
slurm_error("pyxis: error: a container with name \"%s\" does not exist, and --container-image is not set",
container_name);
goto fail;
}
context.container.name = container_name;
container_name = NULL;
} else {
ret = xasprintf(&context.container.name, "pyxis_%u.%u", context.job.jobid, context.job.stepid);
if (ret < 0)
goto fail;
context.container.temporary = true;
}
if (context.args->container_save != NULL)
context.container.save_path = strdup(context.args->container_save);
rv = 0;
fail:
/*
* Errors from user_init() are not propagated back to srun. Rather than fail here and have srun
* report rc=0 (success), we return 0 here and throw the error in task_init()
* instead, which will properly propagate the error back to srun.
*
* See https://bugs.schedmd.com/show_bug.cgi?id=7573 for more details.
*/
if (rv != 0)
slurm_debug("pyxis: user_init() failed with rc=%d; postponing error for now, will report later", rv);
context.user_init_rv = rv;
free(container_name);
return (0);
}
static int spank_copy_env(spank_t sp, const char *from, const char *to, int overwrite)
{
char buf[256];
spank_err_t rc;
rc = spank_getenv(sp, from, buf, sizeof(buf));
if (rc == ESPANK_ENV_NOEXIST)
return (0);
else if (rc != ESPANK_SUCCESS)
return (-1);
rc = spank_setenv(sp, to, buf, overwrite);
if (rc != ESPANK_SUCCESS) {
slurm_error("pyxis: failed to set %s: %s", to, spank_strerror(rc));
return (-1);
}
return (0);
}
static bool pytorch_setup_needed(spank_t sp)
{
spank_err_t rc;
rc = spank_getenv(sp, "PYTORCH_VERSION", NULL, 0);
if (rc == ESPANK_ENV_NOEXIST || rc != ESPANK_NOSPACE)
return (false);
return (true);
}
static struct {
const char *from;
const char *to;
} pytorch_remap_list[] = {
{ "SLURM_PROCID", "RANK" },