int slurm_getaffinity(pid_t pid, size_t size, cpu_set_t *mask) { int rval; char mstr[1 + CPU_SETSIZE / 4]; CPU_ZERO(mask); /* * The FreeBSD cpuset API is a superset of the Linux API. * In addition to PIDs, it supports threads, interrupts, * jails, and potentially other objects. The first two arguments * to cpuset_*etaffinity() below indicate that the third argument * is a PID. -1 indicates the PID of the calling process. * Linux sched_*etaffinity() uses 0 for this. */ #ifdef __FreeBSD__ rval = cpuset_getaffinity(CPU_LEVEL_WHICH, CPU_WHICH_PID, pid, size, mask); #elif defined(SCHED_GETAFFINITY_THREE_ARGS) rval = sched_getaffinity(pid, size, mask); #else rval = sched_getaffinity(pid, mask); #endif if (rval) { verbose("sched_getaffinity(%d,%zd,0x%s) failed with status %d", pid, size, task_cpuset_to_str(mask, mstr), rval); } else { debug3("sched_getaffinity(%d) = 0x%s", pid, task_cpuset_to_str(mask, mstr)); } return (rval); }
int slurm_setaffinity(pid_t pid, size_t size, const cpu_set_t *mask) { int rval; char mstr[1 + CPU_SETSIZE / 4]; #ifdef __FreeBSD__ rval = cpuset_setaffinity(CPU_LEVEL_WHICH, CPU_WHICH_PID, pid, size, mask); #elif defined(SCHED_GETAFFINITY_THREE_ARGS) rval = sched_setaffinity(pid, size, mask); #else rval = sched_setaffinity(pid, mask); #endif if (rval) { verbose("sched_setaffinity(%d,%zd,0x%s) failed: %m", pid, size, task_cpuset_to_str(mask, mstr)); } return (rval); }
/* user to have to play with the cgroup hierarchy to modify it */ extern int task_cgroup_cpuset_set_task_affinity(stepd_step_rec_t *job) { int fstatus = SLURM_ERROR; #ifndef HAVE_HWLOC error("task/cgroup: plugin not compiled with hwloc support, " "skipping affinity."); return fstatus; #else char mstr[1 + CPU_SETSIZE / 4]; cpu_bind_type_t bind_type; cpu_set_t ts; hwloc_obj_t obj; hwloc_obj_type_t socket_or_node; hwloc_topology_t topology; hwloc_bitmap_t cpuset; hwloc_obj_type_t hwtype; hwloc_obj_type_t req_hwtype; int bind_verbose = 0; int rc = SLURM_SUCCESS; pid_t pid = job->envtp->task_pid; size_t tssize; uint32_t nldoms; uint32_t nsockets; uint32_t ncores; uint32_t npus; uint32_t nobj; uint32_t taskid = job->envtp->localid; uint32_t jntasks = job->node_tasks; uint32_t jnpus; /* Allocate and initialize hwloc objects */ hwloc_topology_init(&topology); hwloc_topology_load(topology); cpuset = hwloc_bitmap_alloc(); int spec_threads = 0; if (job->batch) { jnpus = job->cpus; job->cpus_per_task = job->cpus; } else jnpus = jntasks * job->cpus_per_task; bind_type = job->cpu_bind_type; if ((conf->task_plugin_param & CPU_BIND_VERBOSE) || (bind_type & CPU_BIND_VERBOSE)) bind_verbose = 1 ; if ( hwloc_get_type_depth(topology, HWLOC_OBJ_NODE) > hwloc_get_type_depth(topology, HWLOC_OBJ_SOCKET) ) { /* One socket contains multiple NUMA-nodes * like AMD Opteron 6000 series etc. * In such case, use NUMA-node instead of socket. */ socket_or_node = HWLOC_OBJ_NODE; } else { socket_or_node = HWLOC_OBJ_SOCKET; } if (bind_type & CPU_BIND_NONE) { if (bind_verbose) info("task/cgroup: task[%u] is requesting no affinity", taskid); return 0; } else if (bind_type & CPU_BIND_TO_THREADS) { if (bind_verbose) info("task/cgroup: task[%u] is requesting " "thread level binding",taskid); req_hwtype = HWLOC_OBJ_PU; } else if (bind_type & CPU_BIND_TO_CORES) { if (bind_verbose) info("task/cgroup: task[%u] is requesting " "core level binding",taskid); req_hwtype = HWLOC_OBJ_CORE; } else if (bind_type & CPU_BIND_TO_SOCKETS) { if (bind_verbose) info("task/cgroup: task[%u] is requesting " "socket level binding",taskid); req_hwtype = socket_or_node; } else if (bind_type & CPU_BIND_TO_LDOMS) { if (bind_verbose) info("task/cgroup: task[%u] is requesting " "ldom level binding",taskid); req_hwtype = HWLOC_OBJ_NODE; } else if (bind_type & CPU_BIND_TO_BOARDS) { if (bind_verbose) info("task/cgroup: task[%u] is requesting " "board level binding",taskid); req_hwtype = HWLOC_OBJ_GROUP; } else if (bind_type & bind_mode_ldom) { req_hwtype = HWLOC_OBJ_NODE; } else { if (bind_verbose) info("task/cgroup: task[%u] using core level binding" " by default",taskid); req_hwtype = HWLOC_OBJ_CORE; } /* * Perform the topology detection. It will only get allowed PUs. * Detect in the same time the granularity to use for binding. * The granularity can be relaxed from threads to cores if enough * cores are available as with hyperthread support, ntasks-per-core * param can let us have access to more threads per core for each * task * Revert back to machine granularity if no finer-grained granularity * matching the request is found. This will result in no affinity * applied. * The detected granularity will be used to find where to best place * the task, then the cpu_bind option will be used to relax the * affinity constraint and use more PUs. (i.e. use a core granularity * to dispatch the tasks across the sockets and then provide access * to each task to the cores of its socket.) */ npus = (uint32_t) hwloc_get_nbobjs_by_type(topology, HWLOC_OBJ_PU); ncores = (uint32_t) hwloc_get_nbobjs_by_type(topology, HWLOC_OBJ_CORE); nsockets = (uint32_t) hwloc_get_nbobjs_by_type(topology, socket_or_node); nldoms = (uint32_t) hwloc_get_nbobjs_by_type(topology, HWLOC_OBJ_NODE); //info("PU:%d CORE:%d SOCK:%d LDOM:%d", npus, ncores, nsockets, nldoms); hwtype = HWLOC_OBJ_MACHINE; nobj = 1; if ((job->job_core_spec != NO_VAL16) && (job->job_core_spec & CORE_SPEC_THREAD) && (job->job_core_spec != CORE_SPEC_THREAD)) { spec_threads = job->job_core_spec & (~CORE_SPEC_THREAD); } /* Set this to PU but realise it could be overridden later if we can * fill up a core. */ if (npus >= (jnpus + spec_threads)) { hwtype = HWLOC_OBJ_PU; nobj = npus; } /* Force to bind to Threads */ if (bind_type & CPU_BIND_TO_THREADS) { hwtype = HWLOC_OBJ_PU; nobj = npus; } else if (ncores >= jnpus || bind_type & CPU_BIND_TO_CORES) { hwtype = HWLOC_OBJ_CORE; nobj = ncores; } if (nsockets >= jntasks && bind_type & CPU_BIND_TO_SOCKETS) { hwtype = socket_or_node; nobj = nsockets; } /* * HWLOC returns all the NUMA nodes available regardless of the * number of underlying sockets available (regardless of the allowed * resources). So there is no guarantee that each ldom will be populated * with usable sockets. So add a simple check that at least ensure that * we have as many sockets as ldoms before moving to ldoms granularity */ if (nldoms >= jntasks && nsockets >= nldoms && bind_type & (CPU_BIND_TO_LDOMS | bind_mode_ldom)) { hwtype = HWLOC_OBJ_NODE; nobj = nldoms; } /* * If not enough objects to do the job, revert to no affinity mode */ if (hwloc_compare_types(hwtype, HWLOC_OBJ_MACHINE) == 0) { info("task/cgroup: task[%u] disabling affinity because of %s " "granularity",taskid, hwloc_obj_type_string(hwtype)); if (job->cpu_bind_type & CPU_BIND_VERBOSE) fprintf(stderr,"task/cgroup: task[%u] disabling " "affinity because of %s granularity\n", taskid, hwloc_obj_type_string(hwtype)); } else if ((hwloc_compare_types(hwtype, HWLOC_OBJ_CORE) >= 0) && (nobj < jnpus)) { info("task/cgroup: task[%u] not enough %s objects (%d < %d), " "disabling affinity", taskid, hwloc_obj_type_string(hwtype), nobj, jnpus); if (job->cpu_bind_type & CPU_BIND_VERBOSE) fprintf(stderr, "task/cgroup: task[%u] not enough %s " "objects (%d < %d), disabling affinity\n", taskid, hwloc_obj_type_string(hwtype), nobj, jnpus); } else if (bind_type & bind_mode) { /* * Explicit binding mode specified by the user * Bind the taskid in accordance with the specified mode */ obj = hwloc_get_obj_by_type(topology, HWLOC_OBJ_MACHINE, 0); if (bind_verbose) { info("task/cgroup: task[%u] is requesting " "explicit binding mode", taskid); } _get_sched_cpuset(topology, hwtype, req_hwtype, &ts, job); tssize = sizeof(cpu_set_t); fstatus = SLURM_SUCCESS; _validate_mask(taskid, obj, &ts); if ((rc = sched_setaffinity(pid, tssize, &ts))) { error("task/cgroup: task[%u] unable to set " "mask 0x%s", taskid, task_cpuset_to_str(&ts, mstr)); error("sched_setaffinity rc = %d", rc); fstatus = SLURM_ERROR; } else if (bind_verbose) { info("task/cgroup: task[%u] mask 0x%s", taskid, task_cpuset_to_str(&ts, mstr)); } task_slurm_chkaffinity(&ts, job, rc); } else { /* * Bind the detected object to the taskid, respecting the * granularity, using the designated or default distribution * method (block or cyclic). */ char *str = NULL; if (bind_verbose) { info("task/cgroup: task[%u] using %s granularity dist %u", taskid, hwloc_obj_type_string(hwtype), job->task_dist); } /* * See srun man page for detailed information on --distribution * option. * * You can see the equivalent code for the * task/affinity plugin in * src/plugins/task/affinity/dist_tasks.c, around line 368 */ switch (job->task_dist & SLURM_DIST_NODESOCKMASK) { case SLURM_DIST_BLOCK_BLOCK: case SLURM_DIST_CYCLIC_BLOCK: case SLURM_DIST_PLANE: /* tasks are distributed in blocks within a plane */ _task_cgroup_cpuset_dist_block(topology, hwtype, req_hwtype, nobj, job, bind_verbose, cpuset); break; case SLURM_DIST_ARBITRARY: case SLURM_DIST_BLOCK: case SLURM_DIST_CYCLIC: case SLURM_DIST_UNKNOWN: if (slurm_get_select_type_param() & CR_CORE_DEFAULT_DIST_BLOCK) { _task_cgroup_cpuset_dist_block(topology, hwtype, req_hwtype, nobj, job, bind_verbose, cpuset); break; } /* * We want to fall through here if we aren't doing a * default dist block. */ default: _task_cgroup_cpuset_dist_cyclic(topology, hwtype, req_hwtype, job, bind_verbose, cpuset); break; } hwloc_bitmap_asprintf(&str, cpuset); tssize = sizeof(cpu_set_t); if (hwloc_cpuset_to_glibc_sched_affinity(topology, cpuset, &ts, tssize) == 0) { fstatus = SLURM_SUCCESS; if ((rc = sched_setaffinity(pid, tssize, &ts))) { error("task/cgroup: task[%u] unable to set " "taskset '%s'", taskid, str); fstatus = SLURM_ERROR; } else if (bind_verbose) { info("task/cgroup: task[%u] set taskset '%s'", taskid, str); } task_slurm_chkaffinity(&ts, job, rc); } else { error("task/cgroup: task[%u] unable to build " "taskset '%s'",taskid,str); fstatus = SLURM_ERROR; } if (str) free(str); } /* Destroy hwloc objects */ hwloc_bitmap_free(cpuset); hwloc_topology_destroy(topology); return fstatus; #endif }