[simgrid.git] / src / msg / msg_vm.c

/* Copyright (c) 2012. The SimGrid Team. All rights reserved.               */

/* This program is free software; you can redistribute it and/or modify it
 * under the terms of the license (GNU LGPL) which comes with this package. */

// QUESTIONS:
// 1./ check how and where a new VM is added to the list of the hosts
// 2./ Diff between SIMIX_Actions and SURF_Actions
// => SIMIX_actions : point synchro entre processus de niveau (theoretically speaking I do not have to create such SIMIX_ACTION
// =>  Surf_Actions

// TODO
//      MSG_TRACE can be revisited in order to use  the host
//      To implement a mixed model between workstation and vm_workstation,
//     please give a look at surf_model_private_t model_private at SURF Level and to the share resource functions
//     double (*share_resources) (double now);
//      For the action into the vm workstation model, we should be able to leverage the usual one (and if needed, look at
//              the workstation model.

#include "msg_private.h"
#include "xbt/sysdep.h"
#include "xbt/log.h"

XBT_LOG_NEW_DEFAULT_SUBCATEGORY(msg_vm, msg,
                                "Cloud-oriented parts of the MSG API");


/* **** ******** GENERAL ********* **** */

/** \ingroup m_vm_management
 * \brief Returns the value of a given vm property
 *
 * \param vm a vm
 * \param name a property name
 * \return value of a property (or NULL if property not set)
 */

const char *MSG_vm_get_property_value(msg_vm_t vm, const char *name)
{
  return MSG_host_get_property_value(vm, name);
}

/** \ingroup m_vm_management
 * \brief Returns a xbt_dict_t consisting of the list of properties assigned to this host
 *
 * \param vm a vm
 * \return a dict containing the properties
 */
xbt_dict_t MSG_vm_get_properties(msg_vm_t vm)
{
  xbt_assert((vm != NULL), "Invalid parameters (vm is NULL)");

  return (simcall_host_get_properties(vm));
}

/** \ingroup m_host_management
 * \brief Change the value of a given host property
 *
 * \param host a host
 * \param name a property name
 * \param value what to change the property to
 * \param free_ctn the freeing function to use to kill the value on need
 */
void MSG_vm_set_property_value(msg_vm_t vm, const char *name, void *value,void_f_pvoid_t free_ctn) {

  xbt_dict_set(MSG_host_get_properties(vm), name, value,free_ctn);
}

/** \ingroup msg_vm_management
 * \brief Finds a msg_vm_t using its name.
 *
 * This is a name directory service
 * \param name the name of a vm.
 * \return the corresponding vm
 *
 * Please note that a VM is a specific host. Hence, you should give a different name
 * for each VM/PM.
 */

msg_vm_t MSG_vm_get_by_name(const char *name){
        return MSG_get_host_by_name(name);
}

/** \ingroup m_vm_management
 *
 * \brief Return the name of the #msg_host_t.
 *
 * This functions checks whether \a host is a valid pointer or not and return
   its name.
 */
const char *MSG_vm_get_name(msg_vm_t vm) {
  return MSG_host_get_name(vm);
}

/* **** ******** MSG vm actions ********* **** */

/** @brief Create a new VM (the VM is just attached to the location but it is not started yet).
 *  @ingroup msg_VMs*
 *
 * Please note that a VM is a specific host. Hence, you should give a different name
 * for each VM/PM.
 */
msg_vm_t MSG_vm_create(msg_host_t ind_host, const char *name,
                                             int core_nb, int mem_cap, int net_cap){

  // Note new and vm_workstation refer to the same area (due to the lib/dict appraoch)
  msg_vm_t new = NULL;
  void *ind_vm_workstation =  NULL;
  // Ask simix to create the surf vm resource
  ind_vm_workstation = simcall_vm_create(name,ind_host);
  new = (msg_vm_t) __MSG_host_create(ind_vm_workstation);

  MSG_vm_set_property_value(new, "CORE_NB", bprintf("%d", core_nb), free);
  MSG_vm_set_property_value(new, "MEM_CAP", bprintf("%d", mem_cap), free);
  MSG_vm_set_property_value(new, "NET_CAP", bprintf("%d", net_cap), free);

  XBT_DEBUG("A new VM has been created");
  // TODO check whether the vm (i.e the virtual host) has been correctly added into the list of all hosts.

  #ifdef HAVE_TRACING
  TRACE_msg_vm_create(name, ind_host);
  #endif

  return new;
}

/** @brief Start a vm (ie. boot)
 *  @ingroup msg_VMs
 *
 *  If the VM cannot be started, an exception is generated.
 *
 */
void MSG_vm_start(msg_vm_t vm) {

  //Please note that vm start can raise an exception if the VM cannot be started.
  simcall_vm_start(vm);

  #ifdef HAVE_TRACING
  TRACE_msg_vm_start(vm);
  #endif
}

/* **** Check state of a VM **** */
int __MSG_vm_is_state(msg_vm_t vm, e_msg_vm_state_t state) {
        return simcall_vm_get_state(vm) == state ;
}

/** @brief Returns whether the given VM is currently suspended
 *  @ingroup msg_VMs
 */
int MSG_vm_is_suspended(msg_vm_t vm) {
        return __MSG_vm_is_state(vm, msg_vm_state_suspended);
}
/** @brief Returns whether the given VM is currently running
 *  @ingroup msg_VMs
 */
int MSG_vm_is_running(msg_vm_t vm) {
  return __MSG_vm_is_state(vm, msg_vm_state_running);
}

// TODO Implement the functions for the different state


/** @brief Immediately kills all processes within the given VM. Any memory that they allocated will be leaked.
 *  @ingroup msg_VMs
 *
 * FIXME: No extra delay occurs. If you want to simulate this too, you want to
 * use a #MSG_process_sleep() or something. I'm not quite sure.
 */
void MSG_vm_shutdown(msg_vm_t vm)
{
  /* msg_vm_t equals to msg_host_t */
  simcall_vm_shutdown(vm);

  // #ifdef HAVE_TRACING
  // TRACE_msg_vm_(vm);
  // #endif
}



/** @brief Migrate the VM to the given host.
 *  @ingroup msg_VMs
 *
 * FIXME: update comments.
 * No migration cost occurs. If you want to simulate this too, you want to use a
 * MSG_task_send() before or after, depending on whether you want to do cold or hot
 * migration.
 */
void MSG_vm_migrate(msg_vm_t vm, msg_host_t destination)
{
  /* some thoughts:
   * - One approach is ...
   *   We first create a new VM (i.e., destination VM) on the destination
   *   physical host. The destination VM will receive the state of the source
   *   VM over network. We will finally destroy the source VM.
   *   - This behavior is similar to the way of migration in the real world.
   *     Even before a migration is completed, we will see a destination VM,
   *     consuming resources.
   *   - We have to relocate all processes. The existing process migraion code
   *     will work for this?
   *   - The name of the VM is a somewhat unique ID in the code. It is tricky
   *     for the destination VM?
   *
   * - Another one is ...
   *   We update the information of the given VM to place it to the destination
   *   physical host.
   *
   * The second one would be easier.
   *   
   */

  #ifdef HAVE_TRACING
  const char *old_pm_name = simcall_vm_get_phys_host(vm);
  msg_host_t old_pm_ind  = xbt_lib_get_elm_or_null(host_lib, old_pm_name);
  #endif

  simcall_vm_migrate(vm, destination);


  #ifdef HAVE_TRACING
  TRACE_msg_vm_change_host(vm, old_pm_ind, destination);
  #endif
}


/** @brief Immediately suspend the execution of all processes within the given VM.
 *  @ingroup msg_VMs
 *
 * This function stops the exection of the VM. All the processes on this VM
 * will pause. The state of the VM is perserved. We can later resume it again.
 *
 * FIXME: No suspension cost occurs. If you want to simulate this too, you want to
 * use a \ref MSG_file_write() before or after, depending on the exact semantic
 * of VM suspend to you.
 */
void MSG_vm_suspend(msg_vm_t vm)
{
  simcall_vm_suspend(vm);

  #ifdef HAVE_TRACING
  TRACE_msg_vm_suspend(vm);
  #endif
}



/** @brief Resume the execution of the VM. All processes on the VM run again.
 *  @ingroup msg_VMs
 *
 * No resume cost occurs. If you want to simulate this too, you want to
 * use a \ref MSG_file_read() before or after, depending on the exact semantic
 * of VM resume to you.
 */
void MSG_vm_resume(msg_vm_t vm)
{
  simcall_vm_resume(vm);

  #ifdef HAVE_TRACING
  TRACE_msg_vm_resume(vm);
  #endif
}

//
///**
// * \ingroup msg_VMs
// * \brief Reboot the VM, restarting all the processes in it.
// */
//void MSG_vm_reboot(msg_vm_t vm)
//{
//  xbt_dynar_t new_processes = xbt_dynar_new(sizeof(msg_process_t),NULL);
//
//  msg_process_t process;
//  unsigned int cpt;
//
//  xbt_dynar_foreach(vm->processes,cpt,process) {
//    msg_process_t new_process = MSG_process_restart(process);
//    xbt_dynar_push_as(new_processes,msg_process_t,new_process);
//
//  }
//
//  xbt_dynar_foreach(new_processes, cpt, process) {
//    MSG_vm_bind(vm,process);
//  }
//
//  xbt_dynar_free(&new_processes);
//}
//

/** @brief Destroy a VM. Destroy the VM object from the simulation.
 *  @ingroup msg_VMs
 */
void MSG_vm_destroy(msg_vm_t vm)
{
  /* First, terminate all processes on the VM */
  simcall_vm_shutdown(vm);

  /* Then, destroy the VM object */
  simcall_vm_destroy(vm);

  #ifdef HAVE_TRACING
  TRACE_msg_vm_end(vm);
  #endif
}