-/* Copyright (c) 2004-2013. The SimGrid Team.
+/* Copyright (c) 2004-2014. The SimGrid Team.
* All rights reserved. */
/* This program is free software; you can redistribute it and/or modify it
*
* \param task a target task
* \param host the host having a multi-core CPU
- * \param mask the value specifying the CPU affinity setting of the task
+ * \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:
if (mask == 0) {
/* 0 means clear */
- xbt_dict_remove_ext(task->simdata->affinity_mask_db, (char *) host, sizeof(host));
+ {
+ /* 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 *) mask, NULL);