-/** \ingroup m_task_management
- * \brief Changes the CPU affinity of a computation task.
- *
- * When pinning the given task to the first CPU core of the given host, use 0x01 for the mask value. Each bit of the
- * mask value corresponds to each CPU core. See taskset(1) on Linux.
- *
- * \param task a target task
- * \param host the host having a multi-core CPU
- * \param mask the bit mask of a new CPU affinity setting for the task
- *
- * Usage:
- * 0. Define a host with multiple cores.
- * \<host id="PM0" power="1E8" core="2"/\>
- *
- * 1. Pin a given task to the first CPU core of a host.
- * MSG_task_set_affinity(task, pm0, 0x01);
- *
- * 2. Pin a given task to the third CPU core of a host. Turn on the third bit of the mask.
- * MSG_task_set_affinity(task, pm0, 0x04); // 0x04 == 100B
- *
- * 3. Pin a given VM to the first CPU core of a host.
- * MSG_vm_set_affinity(vm, pm0, 0x01);
- *
- * See examples/msg/cloud/multicore.c for more information.
- *
- * Note:
- * 1. The current code does not allow an affinity of a task to multiple cores.
- * The mask value 0x03 (i.e., a given task will be executed on the first core or the second core) is not allowed.
- * The mask value 0x01 or 0x02 works. See cpu_cas01.c for details.
- *
- * 2. It is recommended to first compare simulation results in both the Lazy and Full calculation modes
- * (using --cfg=cpu/optim:Full or not). Fix cpu_cas01.c if you find wrong results in the Lazy mode.
- */
-void MSG_task_set_affinity(msg_task_t task, msg_host_t host, unsigned long mask)
-{
- xbt_assert(task, "Invalid parameter");
- xbt_assert(task->simdata, "Invalid parameter");
-
- if (mask == 0) {
- /* 0 means clear */
- /* We need remove_ext() not throwing exception. */
- void *ret = xbt_dict_get_or_null_ext(task->simdata->affinity_mask_db, (char *) host, sizeof(msg_host_t));
- if (ret != NULL)
- xbt_dict_remove_ext(task->simdata->affinity_mask_db, (char *) host, sizeof(host));
- } else
- xbt_dict_set_ext(task->simdata->affinity_mask_db, (char *) host, sizeof(host), (void *)(uintptr_t) mask, NULL);
-
- /* We set affinity data of this task. If the task is being executed, we actually change the affinity setting of the
- * task. Otherwise, this change will be applied when the task is executed. */
- if (!task->simdata->compute) {
- /* task is not yet executed */
- XBT_INFO("set affinity(0x%04lx@%s) for %s (not active now)", mask, MSG_host_get_name(host),
- MSG_task_get_name(task));
- return;
- }
-
- {
- simgrid::simix::Exec *compute = task->simdata->compute;
- msg_host_t host_now = compute->host; // simix_private.h is necessary
- if (host_now != host) {
- /* task is not yet executed on this host */
- XBT_INFO("set affinity(0x%04lx@%s) for %s (not active now)", mask, MSG_host_get_name(host),
- MSG_task_get_name(task));
- return;
- }
-
- /* task is being executed on this host. so change the affinity now */
- {
- /* check it works. remove me if it works. */
- xbt_assert((unsigned long)(uintptr_t) xbt_dict_get_or_null_ext(task->simdata->affinity_mask_db,
- (char *) host, sizeof(msg_host_t)) == mask);
- }
-
- XBT_INFO("set affinity(0x%04lx@%s) for %s", mask, MSG_host_get_name(host), MSG_task_get_name(task));
- simcall_execution_set_affinity(task->simdata->compute, host, mask);
- }
-}