Resource Reservation Low Level Implementation
[QoS Resource Reservation]

Provides CPU resource reservations into the kernel through a kernel API. More...

Data Structures
struct	server_params_t
struct	server_t
	RRES server main structure. More...
struct	task_list
	Used to queue a task as either active or blocked within a server. More...
Files
file	rres.h
	Internal resource reservation header file.
file	rres_dispatch_gsd_2.4.h
	Module interfacing with the Linux scheduler for the purpose of forcing schedule and deschedule of processes belonging to the servers.
file	rres_dispatch_gsd_2.6.h
	Module interfacing with the Linux scheduler for the purpose of forcing schedule and deschedule of processes belonging to the servers.
file	rres_dispatch_new.c
	Module interfacing with the Linux scheduler for the purpose of forcing schedule and deschedule of processes belonging to the servers.
file	rres_dispatch_new.h
	Module interfacing with the Linux scheduler for the purpose of forcing schedule and deschedule of processes belonging to the servers.
file	rres_dispatch_sig.h
	Module interfacing with the Linux scheduler for the purpose of forcing schedule and deschedule of processes belonging to the servers.
file	rres_hooks.h
	Hooks functions declaration and functions to set/unset hooks handlers.
file	rres_interface.h
	RRES Module main interface header.
file	rres_kpi_core.h
	RRES Module main interface header.
file	rres_kpi_protected.h
	RRES Module protected interface header.
file	rres_proc_fs.h
	Support of proc file system.
file	rres_ready_queue.h
	Implementation of an edf queue.
file	rres_ready_queue_eheap.h
	Heap-based implementation of an edf queue.
file	rres_ready_queue_list.h
	List-based implementation of an edf queue.
file	rres_server.h
	Internal resource reservation header file.
file	rres_time.h
	time and clock related functions
file	rres_utils.h
	Utility functions, like list handling.
Defines
#define	for_each_srv(srv, head, list_field, pos)
	Macro used by for_each_*_server to iterate over a server list.
#define	for_each_srv_safe(srv, head, list_field, pos, postmp)
	Macro used against removal risks to iterate over the server list.
#define	for_each_server(srv, pos) for_each_srv((srv), &server_list, slist, (pos))
	Iterate over all servers in the system.
#define	for_each_server_safe(srv, pos, tmppos) for_each_srv_safe((srv), &server_list, slist, (pos), (tmppos))
	Iterate over all servers in the system - safe against removal.
#define	get_task_entry(h) list_entry((h), struct task_list, others)
	Return the ponter to task_list referred by (h).
#define	for_each_ready_task_in_server(__srv, t, pos)
	Loop on all tasks in a server (do not modify the list).
#define	for_each_blocked_task_in_server(__srv, t, pos)
#define	for_each_ready_task_in_server_safe(__srv, t, __pos, __tmp)
	Loop on all tasks in a server.
#define	for_each_blocked_task_in_server_safe(__srv, t, __pos, __tmp)
#define	qos_log_state(__t) qos_log_debug("(%d), state: %ld, prio: %d", (__t)->pid, (__t)->state, (int)(__t)->rt_priority)
	print the state of the task
#define	qos_log_state_simple(__t) qos_log_simple(QOS_DEBUG_LEVEL, "(%d),s:%ld, p:%d", (__t)->pid, (__t)->state, (int)(__t)->rt_priority)
	print the state of the task (without any other debug info)
#define	SCHED_OTHER SCHED_NORMAL
#define	STOP_PRIORITY -2100
	priority to force linux descheduling
#define	qos_log_state(__t) qos_log_debug("(%d), state: %ld, prio: %d", (__t)->pid, (__t)->state, (int)(__t)->rt_priority)
	print the state of the task
#define	qos_log_state_simple(__t) qos_log_simple(QOS_DEBUG_LEVEL, "(%d),s:%ld, p:%d", (__t)->pid, (__t)->state, (int)(__t)->rt_priority)
	print the state of the task (without any other debug info)
#define	set_tsk_need_resched(task) do { task->need_resched = 1; } while (0)
	force to call the linux scheduler
#define	GENSCHED_DISABLED 1024
	state of a task that is forced to be descheduled
#define	RRES_DISPATCH_PRIORITY 65
	priority to force linux scheduling
#define	rres_init_sched_param(task) set_task_rr_prio(task, RRES_DISPATCH_PRIORITY)
#define	rres_task_sched_default(task)
#define	QOS_DEBUG_LEVEL RRES_MOD_DEBUG_LEVEL
#define	SCHED_OTHER SCHED_NORMAL
#define	rres_init_sched_param(task) set_task_rr_prio(task, RRES_DISPATCH_PRIORITY)
#define	rres_task_sched_default(task) set_task_rr_prio(task, -1)
#define	SCHED_OTHER SCHED_NORMAL
#define	rres_init_sched_param(task)
#define	rres_task_sched_default(task)
#define	SCHED_OTHER SCHED_NORMAL
#define	MIN_SRV_PERIOD 1000LU
	usec.
#define	MIN_SRV_MAX_BUDGET 0LU
	usec.
#define	MIN_SRV_PERIOD_DEBUG 200000LU
	usec.
#define	QOS_F_DEFAULT 0x00000001
	The server to create is the default one.
#define	QOS_F_SOFT 0x00000002
	Server tasks are scheduled within the reservation, and also by Linux outside.
#define	kal_eheap_key_lt kal_time_lt
#define	RRES_MAX_NUM_SERVERS_BITS 12
#define	RRES_MAX_NUM_SERVERS (1 << RRES_MAX_NUM_SERVERS_BITS)
#define	rq_placeholder_init(p_it) kal_eheap_iterator_init(p_it)
	Inititalize a ready queue placeholder as invalid (item not enqueued).
#define	for_each_ready_server(srv, p_it)
	iterate over ready server list
#define	rq_placeholder_init(p_list_head) INIT_LIST_HEAD_NULL(p_list_head)
	Inititalize a ready queue placeholder as invalid (item not enqueued).
#define	for_each_ready_server(srv, pos) for_each_srv((srv), &ready_queue, rq_ph, (pos))
	iterate over ready server list
#define	U_LUB2 (U_LUB+r2bw_c(1,100))
	This adds a tolerance to U_LUB as defined for QRES/QSUP, so to avoid that RRESMOD notifies a system overload when QRES/QSUP do not.
#define	CPU_KHZ_TYPE unsigned long
#define	do_gettimeofday(__tv) gettimeofday((__tv), NULL);
#define	INIT_LIST_HEAD_NULL(ptr) do { (ptr)->prev = NULL; (ptr)->next = NULL; } while (0)
#define	list_add_ordered(head, obj_type, obj, list_field, ord_field, ret)
	add an object in an ordered list insert in the (head) list the (obj) of type (obj_type), ordered in increasing order by field (ord_field) of (obj) example list_add_ordered (ready_list, server_t, srv, rq_ph, deadline, ret) NOTE: in the parameters description "" are used for argument that are name and not variables.
Typedefs
typedef struct server_params_t	server_params_t
typedef struct server_t *	server_p
	Avoids circular dependencies.
typedef struct list_head	rq_placeholder_t
	Ready queue placeholder, useful for being embedded within an enqueued item for subsequenct extraction.
typedef struct server_t	server_t
Functions
qos_rv	rres_init (void)
	Initialise server lists, timers, and algorithm related data, then call rres_schedule().
qos_rv	rres_cleanup (void)
	Destroy all servers in the system.
qos_rv	rres_cleanup_default_server_nosched (server_t *srv)
	Detach all the tasks served by the default server and cleanup the server.
qos_rv	rres_detach_task_nosched (server_t srv, struct task_struct task)
qos_rv	rres_move_nosched (server_t new_srv, struct task_struct task)
	Move into the specified server the specified task.
void	rres_schedule (void)
	Activate the server due to a new job arrival or add a pending request of activation if already active.
void	recharge (server_t *srv)
	Recharge the budget and update the deadline to the old value plus the server period.
void	recharge_reset_from_now (server_t *srv)
	recharge the budget and set the deadline to the actual time plus the server period
qos_rv	rres_on_task_block (struct task_struct *task)
qos_rv	rres_on_task_unblock (struct task_struct *task)
static qos_bool_t	is_in_default_server (struct task_struct *t)
	Check if the task is served by the default server.
static qos_bool_t	is_default_server (server_t *srv)
	It returns true if the server is the default server.
void	rres_stop (server_t *srv)
	Stop all tasks handled by the server.
void	rres_dispatch (server_t *srv)
	Dispatch (force scheduling) of all tasks handled by the server.
void	stop_task_safe (server_t srv, struct task_struct task)
void	dispatch_task_safe (server_t srv, struct task_struct task)
static void	kal_force_reschedule (void)
int	task_ready (struct task_struct *task)
	return true if task is ready to run (task's state = TASK_RUNNING in Linux)
void	rres_init_sched_param (struct task_struct *task)
void	rres_task_sched_default (struct task_struct *task)
void	stop_task (struct task_struct *t)
	Make a task not schedulable by Linux scheduler.
void	dispatch_task (struct task_struct *t)
	Force Linux to schedule this task (or one of the task of the same server).
static void	rres_idle_cpu (void)
	Forces scheduling of the Linux idle task.
static void	rres_dispatch_setup (server_t *srv)
int	task_ready (kal_task_t *task)
	return true if task is ready to run (task's state = TASK_RUNNING in Linux)
void	rres_init_sched_param (kal_task_t *task)
void	rres_task_sched_default (kal_task_t *task)
void	activate_task_local (kal_task_t *task)
void	deactivate_task_local (kal_task_t *task)
void	stop_task (kal_task_t *t)
	Make a task not schedulable by the Linux scheduler.
void	dispatch_task (kal_task_t *t)
	Allow the Linux scheduler to schedule this task.
void	activate_task_local (struct task_struct *task)
void	deactivate_task_local (struct task_struct *task)
int	check_gensched_hooks (void)
	Return true if hooks are not initialised.
void	set_gensched_hooks (void)
	Set scheduler hooks.
void	unset_gensched_hooks (void)
	Unset scheduler hooks.
static struct task_list *	rres_find_task_list (kal_task_t *task)
static server_t *	rres_find_by_task (kal_task_t *task)
	Return the pointer to the server the task is attached to, or NULL.
int	rres_init_module (void)
	Initialise rres module.
void	rres_cleanup_module (void)
	Cleanup rres module.
qos_rv	rres_create_server (server_t **new_srv, qres_time_t max_budget, qres_time_t period, unsigned long flags)
	Create a new server for task t.
qos_rv	rres_init_server (server_t *new_srv, qres_time_t max_budget, qres_time_t period, unsigned long flags)
	Initialize an already allocated server_t (or derived class).
qos_rv	rres_attach_task (server_t srv, struct task_struct task)
	Attach a task to an existing (possibly empty) server.
qos_rv	rres_detach_task (server_t srv, struct task_struct task)
	Detach specified task from its own RRES server.
qos_rv	rres_destroy_server (server_t *rres)
	Destroy the specified server.
qos_rv	rres_cleanup_server (server_t *rres)
	Cleanup the specified server, which must already be empty.
qos_rv	rres_check_destroy (server_t *srv)
	Check if server empty and, if appropriate for the server flags, destroy it.
server_t *	rres_find_by_id (qres_sid_t sid)
	Return the pointer to the server with identification number "id".
qres_sid_t	rres_get_sid (server_t *rres)
	Returns a server unique identifier.
qos_rv	rres_set_params (server_t *rres, qres_time_t budget, qres_time_t period)
	Set budget and period of RRES server (us).
qos_rv	rres_get_params (server_t rres, qres_time_t budget, qres_time_t *period)
	Get RRES scheduling params (us).
qos_rv	rres_set_budget (server_t *rres, qres_time_t budget)
	Set budget of RRES server (us).
static qres_time_t	rres_get_curr_budget (server_t *srv)
	Get remaining budget for the current server instance (us).
qres_time_t	rres_get_period (server_t *rres)
	Get RRES server period (us).
static qos_rv	rres_get_deadline (server_t rres, struct timespec p_deadline)
	Get RRES current deadline (timespec).
static unsigned long	rres_get_flags (server_t *rres)
	Get RRES server flags.
qres_time_t	rres_get_exec_time (server_t *rres)
	Get execution time since server creation (clocks).
server_t *	rres_get_default_server (void)
	Get pointer to default server.
qos_rv	rres_init_default_server (server_t *srv, qres_time_t Q, qres_time_t P, unsigned long flags)
	Initialize the default server.
int	rres_has_server (struct task_struct *t)
	returns true if the task is served by any server
int	rres_empty (server_t *srv)
	return true if the server has no task to serve
int	rres_running (server_t *srv)
	Check if the server is currently running.
static struct task_struct *	rres_any_ready_task (server_t *srv)
	Just return one of the attached ready tasks, or NULL if none exists.
static struct task_struct *	rres_any_blocked_task (server_t *srv)
	Just return one of the attached blocked tasks, or NULL if none exists.
static kal_lock_t *	rres_get_spinlock (void)
static server_t *	rres_find_by_task (struct task_struct *task)
	Return the pointer to the server the task belong to.
qos_rv	rres_init_server (server_t p_server, server_params_t p_params)
	Initialize an already allocated server_t (or derived class).
qos_rv	rres_get_params (server_t p_server, server_params_t p_params)
	Get RRES scheduling params.
qos_rv	rres_set_params (server_t p_server, server_params_t p_params)
	Set RRES scheduling params.
qos_rv	_rres_cleanup_server (server_t *srv)
	Non-virtual server destructor.
qos_bw_t	_rres_get_bandwidth (server_t *srv)
	Non-virtual bandwidth retrieval function.
int	rres_has_ready_tasks (server_t *srv)
static qos_bw_t	rres_get_bandwidth (server_t *srv)
	Return the approved bandwidth for the server.
static qos_bw_t	rres_set_current_bandwidth (server_t *srv, qos_bw_t U_approved)
	This function sets the current bandwidth U_current as specified in the supplied parameter, updating the global variables U_tot and U_active_tot.
static qos_bw_t	rres_update_current_bandwidth (server_t *srv)
static qos_bw_t	rres_get_current_bandwidth (server_t *srv)
	Return the current bandwidth allocated to the server.
int	rres_proc_register (void)
void	rres_proc_unregister (void)
	kal_define_eheap (kal_time_t, server_p)
typedef	kal_eheap_iterator_t (kal_time_t, server_p) rq_placeholder_t
	Ready queue placeholder, useful for being embedded within an enqueued item for subsequenct extraction.
	kal_eheap_t (kal_time_t, server_p) eheap
	Heap of ready servers, min-ordered by abs deadline.
static server_t *	get_highest_priority_server (void)
	return a pointer to the highest priority server (the first of EDF queue)
static int	ready_queue_empty (void)
	return true if the ready queue is empty (no ready server in the system)
static int	srv_alone (server_t *srv)
	return true if the server is the only ready server in the system
static int	in_ready_queue (server_t *srv)
	return true if the server is in ready queue
static void	ready_queue_remove (server_t *srv)
	Remove the server from ready queue.
static qos_rv	rres_edf_init (void)
static void	rres_edf_cleanup (void)
static qos_rv	ready_queue_add (server_t *srv)
	Add the server to ready queue, ordered by deadline (EDF).
static void	rres_set_weight (server_t *srv, unsigned int weight)
	Set the user-supplied server weight, that may be used by some scheduling policies (i.e., shrub).
static unsigned int	rres_get_weight (server_t *srv)
static long long	llimd (long long ll, int mult, int div)
static unsigned long long int	us2clock (unsigned long u)
static unsigned long int	clock2ms (unsigned long long c)
static unsigned long int	clock2us (unsigned long long c)
static unsigned long int	clock2jiffies (unsigned long long c)
static unsigned long long	sched_read_clock (void)
static unsigned long	sched_read_clock_us (void)
static void	rres_init_time (void)
static void	rres_sample_time (void)
	Sample the current time, with the best available precision, into sched_time.
static unsigned long int	clock2subjiffies (unsigned long long c)
static void	list_del_null (struct list_head *entry)
	Remove from list and set to NULL pointers that point to next and previous objects.
Variables
spinlock_t generic_scheduler_lock	__cacheline_aligned
	used for spinlock on hook handlers and timer handler
struct list_head	server_list
	list of the servers
kal_time_t	last_update_time
	time of last budget updating
spinlock_t	rres_lock
struct proc_dir_entry *	qres_proc_root
	pointer to qres proc_fs root directory (/proc/qres)
struct list_head	ready_queue
	List of ready servers, min-ordered by abs deadline.
qos_bw_t	U_tot
	Total allocated bandwidth.
kal_time_t	sched_time
	used to avoid reading too frequently the time.
unsigned int	cpu_khz
unsigned	fast_gettimeoffset_quotient

Detailed Description

Provides CPU resource reservations into the kernel through a kernel API.

Provides CPU core resource reservations into the kernel through a kernel API.

Define Documentation

#define CPU_KHZ_TYPE unsigned long

Definition at line 22 of file rres_time.h.

#define do_gettimeofday ( __tv ) gettimeofday((__tv), NULL);

Definition at line 33 of file rres_time.h.

#define for_each_blocked_task_in_server	(	__srv,
		t,
		pos	)

Value:

for ((pos) = (__srv)->blocked_tasks.next, prefetch((pos)->next); \
        (t) = (list_entry((pos), struct task_list, node))->task, (pos) != &((__srv)->blocked_tasks); \
                (pos) = (pos)->next, prefetch((pos)->next))

Definition at line 127 of file rres.h.

#define for_each_blocked_task_in_server_safe	(	__srv,
		t,
		__pos,
		__tmp	)

Value:

for ((__pos) = (__srv)->blocked_tasks.next, __tmp = (__pos)->next; \
        (t) = (list_entry((__pos), struct task_list, node))->task, (__pos) != &((__srv)->blocked_tasks); \
                (__pos) = (__tmp), __tmp = (__pos)->next)

Definition at line 145 of file rres.h.

#define for_each_ready_server	(	srv,
		pos		)	for_each_srv((srv), &ready_queue, rq_ph, (pos))

iterate over ready server list

Parameters:

srv,:

(server_t *) variable for "current" server (used inside the loop)
pos: (rq_placeholder_t *) temporal variable used to iterate (not used in following loop block)

Definition at line 44 of file rres_ready_queue_list.h.

#define for_each_ready_server	(	srv,
		p_it		)

Value:

for ( \
    kal_eheap_begin(&eheap, (p_it)); \
    kal_eheap_next(&eheap, (p_it), NULL, &(srv)) == QOS_OK); \
    /* Increment not necessary, already made by kal_eheap_next */ \
  )

iterate over ready server list

Parameters:

srv,:

(server_t *) variable for "current" server (used inside the loop) p_it: (rq_placeholder_t *) temporal variable used to iterate (not used in following loop block)

Definition at line 51 of file rres_ready_queue_eheap.h.

#define for_each_ready_task_in_server	(	__srv,
		t,
		pos	)

Value:

for ((pos) = (__srv)->ready_tasks.next, prefetch((pos)->next); \
        (t) = (list_entry((pos), struct task_list, node))->task, (pos) != &((__srv)->ready_tasks); \
                (pos) = (pos)->next, prefetch((pos)->next))

Loop on all tasks in a server (do not modify the list).

Parameters:

	__srv	(server_t *) server that contains the list of tasks
	t	(struct task_struct *) pointer to "current" task in iteration
	pos	(list_head *) temporary variable used for iteration

Note:: : t is modified by this macro; t is not valid outside (after) loop;

Definition at line 122 of file rres.h.

Referenced by rres_dispatch(), and rres_stop().

#define for_each_ready_task_in_server_safe	(	__srv,
		t,
		__pos,
		__tmp	)

Value:

for ((__pos) = (__srv)->ready_tasks.next, __tmp = (__pos)->next; \
        (t) = (list_entry((__pos), struct task_list, node))->task, (__pos) != &((__srv)->ready_tasks); \
                (__pos) = (__tmp), __tmp = (__pos)->next)

Loop on all tasks in a server.

use this instead of for_each_task_in_server() if you need to modify the list (adding or removing an entry)

Parameters:

	__srv	(server_t *) server that contains the list of tasks
	t	(struct task_struct *) pointer to "current" task in iteration
	pos	(list_head *) temporary variable used for iteration

Note:: : t is modified by this macro; t is not valid outside (after) loop;

Definition at line 140 of file rres.h.

#define for_each_server	(	srv,
		pos		)	for_each_srv((srv), &server_list, slist, (pos))

Iterate over all servers in the system.

Parameters:

	srv	(server_t *) variable for "current" server (used inside the loop)
	pos	(struct list_head *) temporal variable used to iterate (not used in following loop block)

Definition at line 103 of file rres.h.

Referenced by qres_update_bandwidths(), rres_find_by_id(), and update_budgets().

#define for_each_server_safe	(	srv,
		pos,
		tmppos	)	for_each_srv_safe((srv), &server_list, slist, (pos), (tmppos))

Iterate over all servers in the system - safe against removal.

Parameters:

	srv	(server_t *) variable for "current" server (used inside the loop)
	pos	(struct list_head *) temporal variable used to iterate (not used in following loop block)
	tmppos	(struct list_head *) temporal variable used to store temporarily the pos variable used during removal

Definition at line 110 of file rres.h.

Referenced by qres_cleanup(), and rres_cleanup().

#define for_each_srv	(	srv,
		head,
		list_field,
		pos	)

Value:

for ((pos) = (head)->next, prefetch((pos)->next); \
        (srv) = (list_entry((pos), server_t, list_field)), (pos) != (head); \
                (pos) = (pos)->next, prefetch((pos)->next))

Macro used by for_each_*_server to iterate over a server list.

Parameters:

	srv	(server_t *) variable for "current" server (used inside the loop)
	head	(struct list_head *) head of the list of servers (ready, recharging etc.)
	list_field	("name of field") name of field used to insert the object in the list(e.g. slist)
	pos	(struct list_head *) temporal variable used to iterate (not used in following loop block)

Definition at line 81 of file rres.h.

#define for_each_srv_safe	(	srv,
		head,
		list_field,
		pos,
		postmp	)

Value:

for (pos = (head)->next, postmp = pos->next; \
         (srv) = (list_entry((pos), server_t, list_field)), pos != (head); \
         pos = postmp, postmp = pos->next)

Macro used against removal risks to iterate over the server list.

Parameters:

	srv	(server_t *) variable for "current" server (used inside the loop)
	head	(struct list_head *) head of the list of servers (ready, recharging etc.) list_field ("name of field") name of field used to insert the object in the list(e.g. slist)
	pos	(struct list_head *) temporal variable used to iterate (not used in following loop block)
	tmppos	(struct list_head *) temporal variable used to store temporarily the pos variable used during removal

Definition at line 94 of file rres.h.

#define GENSCHED_DISABLED 1024

state of a task that is forced to be descheduled

Definition at line 26 of file rres_dispatch_gsd_2.6.h.

#define get_task_entry ( h ) list_entry((h), struct task_list, others)

Return the ponter to task_list referred by (h).

Definition at line 113 of file rres.h.

#define INIT_LIST_HEAD_NULL ( ptr ) do { (ptr)->prev = NULL; (ptr)->next = NULL; } while (0)

Definition at line 18 of file rres_utils.h.

#define kal_eheap_key_lt kal_time_lt

Definition at line 16 of file rres_ready_queue_eheap.h.

#define list_add_ordered	(	head,
		obj_type,
		obj,
		list_field,
		ord_field,
		ret	)

Value:

do { \
  struct list_head *h; \
  if (list_empty(&head)) { \
    list_add(&((obj)->list_field ), &(head)); \
    goto __ret1; \
  } else { \
    for (h = (head).next; h != &(head); h = h->next) { \
      if ((list_entry(h, struct obj_type, list_field)->ord_field) > (obj)->ord_field) { \
        break; \
      } \
    } \
    list_add_tail(&((obj)->list_field), h); \
  } \
  if (&((obj)->list_field) == (head).next) { \
    goto __ret1; \
  } \
  (ret) = 0; \
  break; \
__ret1: \
  (ret) = 1; \
} while (0)

add an object in an ordered list insert in the (head) list the (obj) of type (obj_type), ordered in increasing order by field (ord_field) of (obj) example list_add_ordered (ready_list, server_t, srv, rq_ph, deadline, ret) NOTE: in the parameters description "" are used for argument that are name and not variables.

Parameters:

head,:

(struct list_head * ) head of the list
obj_type: ("object type") type of each element of the list
obj: (obj_type object) object that must be added to the list list_field: ("name of field") name of field used to insert the object in the list
ord_field: ("name of filed") name of filed the list is ordered by
ret: (int) return value is put here
return 1 if the object is inserted at the beginning of the list
return 0 otherwise

Definition at line 35 of file rres_utils.h.

#define MIN_SRV_MAX_BUDGET 0LU

usec.

Minimum allowed server budget (HRT)

Definition at line 28 of file rres_interface.h.

Referenced by qos_func_define(), and rres_init_server().

#define MIN_SRV_PERIOD 1000LU

usec.

Todo:: (high) use types defined in qos_types.h instead of using primitive types likes long long

Minimum allowed server period (HRT)

Definition at line 27 of file rres_interface.h.

Referenced by qos_func_define(), and rres_init_server().

#define MIN_SRV_PERIOD_DEBUG 200000LU

usec.

Minimum allowed server period while debugging

Definition at line 34 of file rres_interface.h.

Referenced by rres_init_server().

#define QOS_DEBUG_LEVEL RRES_MOD_DEBUG_LEVEL

Definition at line 25 of file rres_dispatch_new.c.

#define QOS_F_DEFAULT 0x00000001

The server to create is the default one.

Note:: Only one default server may exist into the system, and must be created by root.

Definition at line 31 of file rres_kpi_core.h.

#define QOS_F_SOFT 0x00000002

Server tasks are scheduled within the reservation, and also by Linux outside.

Note:: Supervisor configuration may allow or deny the requesting user to use this flag.

Definition at line 38 of file rres_kpi_core.h.

#define qos_log_state ( __t ) qos_log_debug("(%d), state: %ld, prio: %d", (__t)->pid, (__t)->state, (int)(__t)->rt_priority)

print the state of the task

Definition at line 29 of file rres_dispatch_gsd_2.4.h.

#define qos_log_state ( __t ) qos_log_debug("(%d), state: %ld, prio: %d", (__t)->pid, (__t)->state, (int)(__t)->rt_priority)

print the state of the task

Definition at line 12 of file rres_dispatch.h.

#define qos_log_state_simple ( __t ) qos_log_simple(QOS_DEBUG_LEVEL, "(%d),s:%ld, p:%d", (__t)->pid, (__t)->state, (int)(__t)->rt_priority)

print the state of the task (without any other debug info)

Definition at line 32 of file rres_dispatch_gsd_2.4.h.

#define qos_log_state_simple ( __t ) qos_log_simple(QOS_DEBUG_LEVEL, "(%d),s:%ld, p:%d", (__t)->pid, (__t)->state, (int)(__t)->rt_priority)

print the state of the task (without any other debug info)

Definition at line 15 of file rres_dispatch.h.

#define rq_placeholder_init ( p_list_head ) INIT_LIST_HEAD_NULL(p_list_head)

Inititalize a ready queue placeholder as invalid (item not enqueued).

Definition at line 30 of file rres_ready_queue_list.h.

#define rq_placeholder_init ( p_it ) kal_eheap_iterator_init(p_it)

Inititalize a ready queue placeholder as invalid (item not enqueued).

Definition at line 33 of file rres_ready_queue_eheap.h.

Referenced by rres_init_server().

#define RRES_DISPATCH_PRIORITY 65

priority to force linux scheduling

Definition at line 27 of file rres_dispatch_gsd_2.6.h.

#define rres_init_sched_param ( task )

Definition at line 27 of file rres_dispatch_sig.h.

#define rres_init_sched_param ( task ) set_task_rr_prio(task, RRES_DISPATCH_PRIORITY)

Definition at line 36 of file rres_dispatch_new.h.

#define rres_init_sched_param ( task ) set_task_rr_prio(task, RRES_DISPATCH_PRIORITY)

Definition at line 39 of file rres_dispatch_gsd_2.6.h.

Referenced by dispatch_task_safe(), and rres_attach_task_nosched().

#define RRES_MAX_NUM_SERVERS (1 << RRES_MAX_NUM_SERVERS_BITS)

Definition at line 30 of file rres_ready_queue_eheap.h.

#define RRES_MAX_NUM_SERVERS_BITS 12

Definition at line 29 of file rres_ready_queue_eheap.h.

#define rres_task_sched_default ( task )

Definition at line 30 of file rres_dispatch_sig.h.

#define rres_task_sched_default ( task ) set_task_rr_prio(task, -1)

Definition at line 39 of file rres_dispatch_new.h.

#define rres_task_sched_default ( task )

Value:

do {                                          \
    if (task->state == GENSCHED_DISABLED)       \
      task->state = TASK_RUNNING;               \
    set_task_rr_prio(task, -1);                 \
  } while (0)

Definition at line 42 of file rres_dispatch_gsd_2.6.h.

Referenced by rres_detach_task_nosched(), and stop_task_safe().

#define SCHED_OTHER SCHED_NORMAL

Definition at line 33 of file rres_dispatch_sig.h.

#define SCHED_OTHER SCHED_NORMAL

Definition at line 42 of file rres_dispatch_new.h.

#define SCHED_OTHER SCHED_NORMAL

Definition at line 45 of file rres_dispatch_new.c.

#define SCHED_OTHER SCHED_NORMAL

Definition at line 24 of file rres_dispatch_gsd_2.4.h.

Referenced by main().

#define set_tsk_need_resched ( task ) do { task->need_resched = 1; } while (0)

force to call the linux scheduler

Definition at line 38 of file rres_dispatch_gsd_2.4.h.

#define STOP_PRIORITY -2100

priority to force linux descheduling

Definition at line 26 of file rres_dispatch_gsd_2.4.h.

#define U_LUB2 (U_LUB+r2bw_c(1,100))

This adds a tolerance to U_LUB as defined for QRES/QSUP, so to avoid that RRESMOD notifies a system overload when QRES/QSUP do not.

Definition at line 73 of file rres_server.h.

Referenced by rres_init_server(), rres_set_budget(), rres_set_current_bandwidth(), and rres_set_params().

Typedef Documentation

typedef struct list_head rq_placeholder_t

Ready queue placeholder, useful for being embedded within an enqueued item for subsequenct extraction.

Definition at line 22 of file rres_ready_queue_list.h.

typedef struct server_t* server_p

Avoids circular dependencies.

Definition at line 17 of file rres_ready_queue.h.

typedef struct server_params_t server_params_t

typedef struct server_t server_t

Definition at line 63 of file rres_server.h.

Function Documentation

qos_rv _rres_cleanup_server ( server_t * srv )

Non-virtual server destructor.

Definition at line 855 of file rres.c.

References server_t::id, in_ready_queue(), qos_chk, qos_chk_do, QOS_E_INTERNAL_ERROR, qos_log_crit, qos_log_debug, QOS_OK, QRES_SID_FMT, QRES_TIME_FMT, ready_queue_remove(), rres_empty(), rres_get_default_server(), rres_get_exec_time(), RRES_PARANOID, rres_remove_from_srv_set(), rres_running(), rres_sample_time(), rres_set_current_bandwidth(), and stop_pending_timers().

Referenced by qos_func_define(), and rres_init_server().

qos_bw_t _rres_get_bandwidth ( server_t * srv )

Non-virtual bandwidth retrieval function.

Note:: This function must not be called directly. It is called through srv->get_approved_bw(srv)

Definition at line 188 of file rres.c.

References server_t::max_budget_us, server_t::period_us, and r2bw().

Referenced by _qres_get_bandwidth(), qos_func_define(), and rres_init_server().

void activate_task_local ( struct task_struct * task )

void activate_task_local ( kal_task_t * task )

Referenced by dispatch_task().

int check_gensched_hooks ( void )

Return true if hooks are not initialised.

Definition at line 173 of file rres_hooks.c.

References block_hook, cleanup_hook, continue_hook, fork_hook, stop_hook, and unblock_hook.

Referenced by rres_init_module().

static unsigned long int clock2jiffies ( unsigned long long c ) [inline, static]

Definition at line 42 of file rres_timeOLD.h.

References fast_gettimeoffset_quotient, and llimd().

static unsigned long int clock2ms ( unsigned long long c ) [inline, static]

Definition at line 32 of file rres_timeOLD.h.

References fast_gettimeoffset_quotient, and llimd().

static unsigned long int clock2subjiffies ( unsigned long long c ) [inline, static]

Definition at line 50 of file rres_timeOLD.h.

References cpu_khz, fast_gettimeoffset_quotient, and llimd().

static unsigned long int clock2us ( unsigned long long c ) [inline, static]

Definition at line 37 of file rres_timeOLD.h.

References fast_gettimeoffset_quotient.

void deactivate_task_local ( struct task_struct * task )

void deactivate_task_local ( kal_task_t * task )

Referenced by stop_task().

void dispatch_task ( kal_task_t * t )

Allow the Linux scheduler to schedule this task.

Definition at line 65 of file rres_dispatch_new.c.

References activate_task_local(), and qos_log_debug.

static void dispatch_task ( struct task_struct * t ) [inline]

Force Linux to schedule this task (or one of the task of the same server).

Allow the Linux scheduler to schedule this task.

Definition at line 42 of file rres_dispatch_sig.h.

Referenced by dispatch_task_safe().

void dispatch_task_safe	(	server_t *	srv,
		struct task_struct *	task
	)

static server_t * get_highest_priority_server ( void ) [inline, static]

return a pointer to the highest priority server (the first of EDF queue)

Definition at line 33 of file rres_ready_queue_list.h.

References ready_queue.

Referenced by rres_schedule().

static int in_ready_queue ( server_t * srv ) [inline, static]

return true if the server is in ready queue

Definition at line 58 of file rres_ready_queue_list.h.

Referenced by _rres_cleanup_server(), ready_queue_add(), ready_queue_remove(), rres_deactivate_nosched(), rres_update_budget(), and update_budgets().

static qos_bool_t is_default_server ( server_t * srv ) [inline, static]

It returns true if the server is the default server.

Definition at line 160 of file rres.h.

Referenced by rres_dispatch(), and rres_stop().

static qos_bool_t is_in_default_server ( struct task_struct * t ) [inline, static]

Check if the task is served by the default server.

Definition at line 151 of file rres.h.

References rres_find_by_task().

kal_define_eheap	(	kal_time_t	,
		server_p
	)

typedef kal_eheap_iterator_t	(	kal_time_t	,
		server_p
	)

Ready queue placeholder, useful for being embedded within an enqueued item for subsequenct extraction.

kal_eheap_t	(	kal_time_t	,
		server_p
	)

Heap of ready servers, min-ordered by abs deadline.

static void kal_force_reschedule ( void ) [inline, static]

Definition at line 17 of file rres_dispatch.h.

References set_tsk_need_resched.

Referenced by rres_schedule().

static void list_del_null ( struct list_head * entry ) [inline, static]

Remove from list and set to NULL pointers that point to next and previous objects.

Definition at line 59 of file rres_utils.h.

static long long llimd	(	long long	ll,
		int	mult,
		int	div
	)			`[inline, static]`

Definition at line 74 of file rres_timeOLD.h.

static qos_rv ready_queue_add ( server_t * srv ) [static]

Add the server to ready queue, ordered by deadline (EDF).

Definition at line 83 of file rres_ready_queue_list.h.

References DUMP_STACK, server_t::id, in_ready_queue(), list_add_ordered, qos_log_crit, qos_log_debug, QOS_OK, ready_queue, and ready_queue_remove().

Referenced by iris_hr_reactive_timer_handler(), and rres_activate_nosched().

static int ready_queue_empty ( void ) [inline, static]

return true if the ready queue is empty (no ready server in the system)

Definition at line 48 of file rres_ready_queue_list.h.

References ready_queue.

static void ready_queue_remove ( server_t * srv ) [static]

Remove the server from ready queue.

Definition at line 63 of file rres_ready_queue_list.h.

References server_t::id, in_ready_queue(), list_del_null(), qos_chk_do, qos_log_debug, and server_t::rq_ph.

Referenced by _rres_cleanup_server(), ready_queue_add(), rres_deactivate_nosched(), and rres_update_budget().

void recharge ( server_t * srv )

Recharge the budget and update the deadline to the old value plus the server period.

Definition at line 258 of file rres.c.

References bw2Q(), server_t::c, server_t::deadline, server_t::id, kal_time_add(), KAL_TIME_FMT, KAL_TIME_FMT_ARG, kal_time_le(), kal_usec2time(), server_t::max_budget, server_t::rres_stat::n_rcg, server_t::period, server_t::period_us, QOS_BW_FMT, qos_log_debug, qos_log_warn, rres_update_current_bandwidth(), sched_time, server_t::stat, and U_tot.

Referenced by iris_hr_reactive_timer_handler(), and recharge_reset_from_now().

void recharge_reset_from_now ( server_t * srv )

recharge the budget and set the deadline to the actual time plus the server period

See also:: recharge(server_t *)

Definition at line 283 of file rres.c.

References server_t::c, server_t::deadline, KAL_TIME_US, recharge(), and sched_time.

Referenced by rres_activate_nosched(), and rres_init_server().

static struct task_struct* rres_any_blocked_task ( server_t * srv ) [static, read]

Just return one of the attached blocked tasks, or NULL if none exists.

Definition at line 181 of file rres_interface.h.

References server_t::blocked_tasks, task_list::node, qos_chk_do, qos_mem_valid(), RRES_PARANOID, and task_list::task.

Referenced by qos_func_define(), rres_destroy_server(), and rres_detach_all_tasks_nosched().

static struct task_struct* rres_any_ready_task ( server_t * srv ) [static, read]

Just return one of the attached ready tasks, or NULL if none exists.

Definition at line 170 of file rres_interface.h.

References task_list::node, qos_chk_do, qos_mem_valid(), server_t::ready_tasks, RRES_PARANOID, and task_list::task.

Referenced by qos_func_define(), rres_destroy_server(), and rres_detach_all_tasks_nosched().

qos_rv rres_attach_task	(	server_t *	srv,
		struct task_struct *	task
	)

Attach a task to an existing (possibly empty) server.

qos_rv rres_check_destroy ( server_t * srv )

Check if server empty and, if appropriate for the server flags, destroy it.

This must be explicitly called after any call to functions that may detach tasks from a server leaving it empty, e.g. rres_detach_server(), rres_move(), rres_detach_all_tasks(), in order to enforce non-persistent servers semantics.

Check if server empty and, if appropriate for the server flags, destroy it.

This includes calling rres_schedule() afterwards.

Definition at line 635 of file rres.c.

References server_t::flags, qos_chk_ok_ret, QOS_F_PERSISTENT, QOS_OK, rres_destroy_server(), and rres_empty().

Referenced by qos_func_define(), and rres_cleanup_hook().

qos_rv rres_cleanup ( void )

Destroy all servers in the system.

This is used before unloading the rres module. Servers are destroyed through calls to the rres_destroy_server() function, that performs a virtual call to the destructor using the rres->cleanup() pointer.

Note:: When default server is configured, destroy_server operation on non-default servers is supposed to move threads to the default server. Therefore, it needs to still exist while destroying the other servers, and it should be destroyed last (and infact it is supposed to be created first).

Definition at line 1288 of file rres.c.

References for_each_server_safe, server_t::id, kal_timer_del(), qos_free(), QOS_LEVEL_VERB, qos_log, QOS_OK, rres_destroy_server(), and rres_edf_cleanup().

Referenced by rres_cleanup_module(), and rres_init_module().

qos_rv rres_cleanup_default_server_nosched ( server_t * srv )

Detach all the tasks served by the default server and cleanup the server.

void rres_cleanup_module ( void )

Cleanup rres module.

This part of code is mutually exclusive with other rres*.c parts, even if it uses hook_lock instead of rres_lock.

Definition at line 148 of file rres_init.c.

References hook_lock, qos_chk_ok, qos_log_debug, qos_log_err, qos_log_info, qos_mem_clean(), rres_cleanup(), rres_get_spinlock(), rres_mod_removed, rres_proc_unregister(), and unset_gensched_hooks().

static qos_rv rres_cleanup_server ( server_t * rres ) [inline]

Cleanup the specified server, which must already be empty.

Uninitialize an already allocated server_t, without deallocating it.

Any resource associated to the server pointed to by rres parameter, except the server_t struct itself, is deallocated.

Note:: Before calling this function, ensure the server is empty by calling rres_detach_task(), if needed.

Definition at line 75 of file rres_server.h.

References server_t::cleanup, qos_chk_do, QOS_E_INTERNAL_ERROR, and RRES_PARANOID.

Referenced by rres_destroy_server().

qos_rv rres_create_server	(	server_t **	new_srv,
		qres_time_t	max_budget,
		qres_time_t	period,
		unsigned long	type
	)

Create a new server for task t.

It performs extra operation with respect to rres_create_server if the task is already served by an existing server.

max_budget and period are expressed in usecs.

Create a new server for task t.

It is not schedulable so the scheduler must not be called

Definition at line 896 of file rres.c.

References qos_chk_do, qos_chk_ok_ret, qos_chk_rv, qos_create, QOS_E_INTERNAL_ERROR, QOS_E_NO_MEMORY, QOS_OK, rres_init_server(), and RRES_PARANOID.

Referenced by test_rres_init_module().

qos_rv rres_destroy_server ( server_t * srv )

Destroy the specified server.

All attached tasks are detached and return to the default scheduling policy. Any resource associated to the server pointed to by rres parameter, including the server_t struct itself, is deallocated.

Definition at line 909 of file rres.c.

References qos_chk_do, qos_chk_ok_ret, QOS_E_INTERNAL_ERROR, QOS_E_INVALID_PARAM, qos_free(), QOS_OK, rres_any_blocked_task(), rres_any_ready_task(), rres_cleanup_server(), rres_detach_task(), RRES_PARANOID, and task_list::task.

Referenced by qos_func_define(), rres_check_destroy(), rres_cleanup(), and test_rres_init_module().

qos_rv rres_detach_task	(	server_t *	srv,
		struct task_struct *	task
	)

Detach specified task from its own RRES server.

Do not automatically destroy the server if it becomes empty.

qos_rv rres_detach_task_nosched	(	server_t *	srv,
		struct task_struct *	task
	)

void rres_dispatch ( server_t * srv )

Dispatch (force scheduling) of all tasks handled by the server.

Definition at line 1143 of file rres.c.

References dispatch_task_safe(), for_each_ready_task_in_server, server_t::id, is_default_server(), qos_log_debug, qos_log_err, RRES_DISPATCH_PRIORITY, and rres_empty().

Referenced by rres_schedule().

static void rres_dispatch_setup ( server_t * srv ) [inline, static]

Definition at line 58 of file rres_dispatch_gsd_2.4.h.

static void rres_edf_cleanup ( void ) [inline, static]

Definition at line 77 of file rres_ready_queue_list.h.

References qos_chk, and ready_queue.

Referenced by rres_cleanup().

static qos_rv rres_edf_init ( void ) [inline, static]

Definition at line 72 of file rres_ready_queue_list.h.

References QOS_OK, and ready_queue.

Referenced by rres_init().

int rres_empty ( server_t * srv )

return true if the server has no task to serve

Return true is the specified server has no attached tasks.

return true if the server has no task to serve

Return true is the specified server has no attached tasks.

Definition at line 112 of file rres.c.

References server_t::blocked_tasks, and server_t::ready_tasks.

Referenced by _rres_cleanup_server(), iris_hr_reactive_timer_handler(), rres_check_destroy(), rres_cleanup_hook(), rres_detach_task(), rres_dispatch(), rres_schedule(), and rres_stop().

server_t* rres_find_by_id ( qres_sid_t sid )

Return the pointer to the server with identification number "id".

Return NULL if no server with the specified id is found.

Return the pointer to the server with identification number "id".

Note:: : Conversion works fine wrt wrap-arounds of the converted value. Of course, not wrt wrap-arounds of the original TSC value, but it's an unsigned long long, thus, if the system is never shut down, the anomaly repeats every 365 years with a 1.6GHz CPU, or every 146 years with a 4 GHz CPU :-).

Todo:: (low) move this function to time.c/.h and modify qres that call this function; rename sched_* in kal_*

Return the pointer to the server with the specified server id, or NULL if not found.

Todo:: Speed-up in case of many servers, by using a hashmap

Definition at line 144 of file rres.c.

References for_each_server, server_t::id, QRES_SID_NULL, rres_find_by_task(), and srv.

Referenced by new_server_id(), qres_find_by_id(), and test_rres_init_module().

static server_t* rres_find_by_task ( struct task_struct * task ) [inline, static]

Return the pointer to the server the task belong to.

static server_t* rres_find_by_task ( kal_task_t * task ) [inline, static]

Return the pointer to the server the task is attached to, or NULL.

Definition at line 41 of file rres_interface.h.

References rres_find_task_list(), and task_list::srv.

Referenced by is_in_default_server(), qos_func_define(), qres_attach_data_to_task(), qres_retrieve_from_task(), rres_attach_all_tasks_nosched(), rres_attach_task(), rres_attach_task_nosched(), rres_cleanup_hook(), rres_detach_task(), rres_find_by_id(), rres_fork_hook(), rres_has_server(), rres_move_nosched(), and test_rres_init_module().

static struct task_list* rres_find_task_list ( kal_task_t * task ) [static, read]

Definition at line 36 of file rres_interface.h.

Referenced by dispatch_task_safe(), rres_del(), rres_find_by_task(), rres_on_task_block(), rres_on_task_unblock(), rres_stop(), and stop_task_safe().

static qos_bw_t rres_get_bandwidth ( server_t * srv ) [inline, static]

Return the approved bandwidth for the server.

Note:: This may be higher than the bandwidth that is going to be used for the very next server instance, that may be retrieved through rres_get_current_bandwidth().

Definition at line 39 of file rres_kpi_protected.h.

References server_t::get_bandwidth.

Referenced by qos_func_define(), qres_update_bandwidths(), rres_get_actual_budget(), rres_get_params(), and rres_update_current_bandwidth().

static qres_time_t rres_get_curr_budget ( server_t * srv ) [inline, static]

Get remaining budget for the current server instance (us).

Definition at line 120 of file rres_interface.h.

References server_t::c, and kal_time2usec().

Referenced by qos_func_define().

static qos_bw_t rres_get_current_bandwidth ( server_t * srv ) [inline, static]

Return the current bandwidth allocated to the server.

This is the value that is going to be used for the very next server instance, and its value is updated by the rres_update_current_bandwidth() function.

Definition at line 74 of file rres_kpi_protected.h.

References server_t::U_current.

Referenced by qos_func_define().

static qos_rv rres_get_deadline	(	server_t *	rres,
		struct timespec *	p_deadline
	)			`[inline, static]`

Get RRES current deadline (timespec).

Definition at line 128 of file rres_interface.h.

References server_t::deadline, kal_time2timespec(), and QOS_OK.

Referenced by qos_func_define().

server_t* rres_get_default_server ( void )

Get pointer to default server.

Return NULL if default server is not configured

Get pointer to default server.

Return NULL if default server is not configured

Definition at line 1083 of file rres.c.

Referenced by _rres_cleanup_server(), rres_attach_task_nosched(), rres_detach_task(), rres_detach_task_nosched(), rres_init_server(), rres_on_task_block(), and rres_on_task_unblock().

qres_time_t rres_get_exec_time ( server_t * rres )

Get execution time since server creation (clocks).

If srv is the currently running server, then include in the result the elapsed time since the last recharge as well.

Definition at line 1066 of file rres.c.

References server_t::rres_stat::exec_time, kal_time2usec(), kal_time_add(), kal_time_now(), kal_time_sub(), last_update_time, qos_chk_do, QOS_LEVEL_ERROR, qos_log, RRES_PARANOID, and server_t::stat.

Referenced by _rres_cleanup_server(), and qos_func_define().

static unsigned long rres_get_flags ( server_t * rres ) [inline, static]

Get RRES server flags.

Definition at line 134 of file rres_interface.h.

References server_t::flags.

qos_rv rres_get_params	(	server_t *	p_server,
		server_params_t *	p_params
	)

Get RRES scheduling params.

qos_rv rres_get_params	(	server_t *	srv,
		qres_time_t *	budget,
		qres_time_t *	period
	)

Get RRES scheduling params (us).

Definition at line 1035 of file rres.c.

References bw2Q(), server_t::id, server_t::period_us, qos_chk_do, QOS_E_INTERNAL_ERROR, qos_log_debug, QOS_OK, QRES_TIME_FMT, rres_get_bandwidth(), and RRES_PARANOID.

qres_time_t rres_get_period ( server_t * srv )

Get RRES server period (us).

Returns:: 0 if the parameters have been succesfully changed, -1 in case of error

Definition at line 1055 of file rres.c.

References server_t::period_us.

Referenced by qres_update_bandwidths().

qres_sid_t rres_get_sid ( server_t * srv )

Returns a server unique identifier.

Returns:: QRES_SID_NULL in case of error the server ID otherwise

Definition at line 951 of file rres.c.

References server_t::id, and QRES_SID_NULL.

Referenced by qos_func_define().

static kal_lock_t* rres_get_spinlock ( void ) [inline, static]

Definition at line 193 of file rres_interface.h.

References rres_lock.

Referenced by enforce_timer_handler(), iris_hr_reactive_timer_handler(), my_init_module(), qres_cleanup_module(), qres_get_lock(), qres_init_module(), qsup_gw_ks(), rres_block_hook(), rres_cleanup_hook(), rres_cleanup_module(), rres_fork_hook(), rres_init_module(), rres_read_qsup(), rres_unblock_hook(), and test_rres_init_module().

static unsigned int rres_get_weight ( server_t * srv ) [inline, static]

Definition at line 88 of file rres_server.h.

References server_t::weight.

Referenced by qos_func_define().

int rres_has_ready_tasks ( server_t * srv )

Definition at line 514 of file rres.c.

References qos_chk_do, server_t::ready_tasks, and RRES_PARANOID.

Referenced by iris_hr_reactive_timer_handler(), qos_func_define(), rres_activate_nosched(), rres_attach_task_nosched(), rres_cleanup_hook(), rres_deactivate_nosched(), rres_detach_task_nosched(), rres_on_task_block(), rres_on_task_unblock(), rres_schedule(), rres_set_budget(), rres_set_current_bandwidth(), and rres_set_params().

qos_bool_t rres_has_server ( struct task_struct * t )

returns true if the task is served by any server

static void rres_idle_cpu ( void ) [inline, static]

Forces scheduling of the Linux idle task.

Forces scheduling of Linux.

Definition at line 80 of file rres_dispatch_gsd_2.6.h.

References set_tsk_need_resched.

qos_rv rres_init ( void )

Initialise server lists, timers, and algorithm related data, then call rres_schedule().

Definition at line 1262 of file rres.c.

References enforce_timer_handler(), kal_timer_init(), last_update_time, qos_chk_do, qos_chk_ok_ret, qos_create, QOS_E_NO_MEMORY, QOS_OK, rres_edf_init(), rres_init_time(), rres_sample_time(), rres_schedule(), sched_time, and server_list.

Referenced by rres_init_module().

qos_rv rres_init_default_server	(	server_t *	srv,
		qres_time_t	Q,
		qres_time_t	P,
		unsigned long	flags
	)

Initialize the default server.

The default server hosts all tasks that do not explicitly use AQuoSA. After this call, all system tasks have been attached to the default server.

Parameters:

srv

Pointer to an already allocated structure of type server_t (or subtype).

int rres_init_module ( void )

Initialise rres module.

This part of code is mutually exclusive with other rres*.c parts, even if it uses hook_lock instead of rres_lock.

ProcFS-related functions may sleep, so no spinlock should be held

Definition at line 73 of file rres_init.c.

References check_gensched_hooks(), hook_lock, qos_log_crit, qos_log_debug, qos_log_err, QOS_OK, rres_cleanup(), rres_get_spinlock(), rres_init(), rres_proc_register(), rres_sample_time(), and set_gensched_hooks().

void rres_init_sched_param ( kal_task_t * task )

Definition at line 37 of file rres_dispatch_new.c.

References RRES_DISPATCH_PRIORITY, and set_task_rr_prio().

void rres_init_sched_param ( struct task_struct * task )

qos_rv rres_init_server	(	server_t *	p_server,
		server_params_t *	p_params
	)

Initialize an already allocated server_t (or derived class).

qos_rv rres_init_server	(	server_t *	srv,
		qres_time_t	max_budget,
		qres_time_t	period,
		unsigned long	flags
	)

Initialize an already allocated server_t (or derived class).

Todo:: rres_move_*_opt (optimized) functions must replace the above functions

Internal use only It performs checks on parameters max_budget and period are time values expressed in usecs. The server is created empty (with no task attached)

Definition at line 760 of file rres.c.

References _rres_cleanup_server(), _rres_get_bandwidth(), server_t::blocked_tasks, server_t::c, server_t::cleanup, server_t::deadline, server_t::rres_stat::exec_time, server_t::flags, server_t::forbid_reorder, server_t::get_bandwidth, iris_hr_reactive_timer_handler(), kal_time_now(), KAL_TIME_US, kal_timer_init(), kal_usec2time(), server_t::max_budget, server_t::max_budget_us, MAX_BW, MIN_SRV_MAX_BUDGET, MIN_SRV_PERIOD, MIN_SRV_PERIOD_DEBUG, server_t::rres_stat::n_rcg, new_server_id(), server_t::period, server_t::period_us, qos_chk_do, qos_chk_ok_ret, qos_debug_enabled_for, QOS_E_INCONSISTENT_STATE, QOS_E_INTERNAL_ERROR, QOS_E_INVALID_PARAM, QOS_E_SYSTEM_OVERLOAD, QOS_E_UNIMPLEMENTED, QOS_F_DEFAULT, QOS_LEVEL_DEBUG, qos_log_debug, qos_log_err, QOS_OK, qos_return_if_cond, qos_strerror(), QRES_SID_NULL, QRES_TIME_FMT, r2bw(), server_t::reactive, server_t::ready_tasks, recharge_reset_from_now(), server_t::rq_ph, rq_placeholder_init, rres_add_to_srv_set(), rres_attach_all_tasks_nosched(), rres_get_default_server(), RRES_PARANOID, rres_remove_from_srv_set(), rres_sample_time(), rres_set_budget(), server_t::stat, server_t::U_current, U_LUB2, and U_tot.

Referenced by qos_func_define(), and rres_create_server().

static void rres_init_time ( void ) [inline, static]

Definition at line 124 of file rres_time.h.

Referenced by rres_init().

qos_rv rres_move_nosched	(	server_t *	new_srv,
		struct task_struct *	task
	)

Move into the specified server the specified task.

qos_rv rres_on_task_block ( struct task_struct * task )

qos_rv rres_on_task_unblock ( struct task_struct * task )

int rres_proc_register ( void )

Definition at line 250 of file rres_proc_fs.c.

Referenced by rres_init_module().

void rres_proc_unregister ( void )

Definition at line 251 of file rres_proc_fs.c.

Referenced by rres_cleanup_module().

int rres_running ( server_t * srv )

Check if the server is currently running.

Definition at line 1306 of file rres.c.

Referenced by _rres_cleanup_server(), rres_attach_task_nosched(), rres_cleanup_hook(), rres_detach_task(), and rres_on_task_unblock().

static void rres_sample_time ( void ) [inline, static]

Sample the current time, with the best available precision, into sched_time.

Used at every synchronous or asynchronous enter of code flow within rres, in order to avoid too frequent precise reads of the current time.

Definition at line 135 of file rres_time.h.

References KAL_TIME_FMT, KAL_TIME_FMT_ARG, kal_time_now(), and qos_log_debug.

Referenced by _rres_cleanup_server(), enforce_timer_handler(), iris_hr_reactive_timer_handler(), rres_attach_task(), rres_cleanup_hook(), rres_detach_task(), rres_init(), rres_init_module(), rres_init_server(), rres_on_task_block(), and rres_on_task_unblock().

void rres_schedule ( void )

Activate the server due to a new job arrival or add a pending request of activation if already active.

Called when a job ends (tasks blocks) if it was the last active task in the server, remove the server from the ready queue Main RRES server scheduling function.

Update budget of currently running server, if any. Select the earliest deadline server and dispatch it.

Activate the server due to a new job arrival or add a pending request of activation if already active.

If a server is executing, then update its budget. Select the earliest deadline server and, if changed:

stop tasks of the currently executing server
dispatch tasks of the new server

If the currently executing task does not belong to the last selected server for execution, then ask the system scheduler (e.g. Linux scheduler) to deschedule it.

Parameters:

timer

Timer whose callback we are in while calling this function, or NULL. This is useful for avoiding to stop that timer while from its callback, as some kal_timer implementations may not like it (e.g. hrtimer blocks the kernel in such a case).

This check makes the task_list->is_blocked flag no more required, as when we deactivate the last active task, we do not rres_stop() the server anymore (that flag was required in order to avoid a task_stop() on a blocked task, in this event).

Definition at line 1200 of file rres.c.

References get_highest_priority_server(), get_max_time_slice(), server_t::id, kal_force_reschedule(), kal_time2usec(), kal_timer_del(), qos_chk, qos_chk_do, qos_log_debug, qos_mem_valid(), rres_dispatch(), rres_dump, rres_empty(), rres_has_ready_tasks(), rres_stop(), rres_update_budget(), sched_time, set_enforce_timer(), and stop_pending_timers().

Referenced by enforce_timer_handler(), iris_hr_reactive_timer_handler(), rres_attach_task(), rres_cleanup_hook(), rres_detach_task(), rres_init(), rres_on_task_block(), and rres_on_task_unblock().

qos_rv rres_set_budget	(	server_t *	srv,
		qres_time_t	new_budget
	)

Set budget of RRES server (us).

Note:: : Current budget is updated at the next recharge.

Definition at line 1011 of file rres.c.

References server_t::c, server_t::get_bandwidth, kal_time_le(), kal_usec2time(), server_t::max_budget, server_t::max_budget_us, server_t::period_us, qos_chk_do, QOS_E_INTERNAL_ERROR, QOS_E_SYSTEM_OVERLOAD, QOS_OK, r2bw(), rres_has_ready_tasks(), RRES_PARANOID, rres_update_current_bandwidth(), U_LUB2, and U_tot.

Referenced by qres_update_bandwidths(), and rres_init_server().

static qos_bw_t rres_set_current_bandwidth	(	server_t *	srv,
		qos_bw_t	U_approved
	)			`[inline, static]`

This function sets the current bandwidth U_current as specified in the supplied parameter, updating the global variables U_tot and U_active_tot.

Definition at line 46 of file rres_kpi_protected.h.

References QOS_BW_FMT, qos_log_debug, rres_has_ready_tasks(), server_t::U_current, U_LUB2, and U_tot.

Referenced by _rres_cleanup_server(), and rres_update_current_bandwidth().

qos_rv rres_set_params	(	server_t *	p_server,
		server_params_t *	p_params
	)

Set RRES scheduling params.

qos_rv rres_set_params	(	server_t *	srv,
		qres_time_t	new_budget,
		qres_time_t	new_period
	)

Set budget and period of RRES server (us).

Admission control is performed on the basis of the total sum of bandwidths as requested through rres_create_server() and rres_set_params(). Actually, the server is assigned a current bandwidth that may generally be lower than the requested value, for at most a time window of duration equal to the greatest server period (in the worst case).

Note:: Server budget and period start being updated from the next recharge.

Definition at line 970 of file rres.c.

References bw2Q(), server_t::c, server_t::deadline, server_t::get_bandwidth, server_t::id, kal_time2usec(), kal_time_le(), kal_time_lt(), kal_time_sub(), kal_usec2time(), server_t::max_budget, server_t::max_budget_us, server_t::period, server_t::period_us, qos_chk_do, QOS_E_INTERNAL_ERROR, QOS_E_SYSTEM_OVERLOAD, qos_log_debug, QOS_OK, QRES_TIME_FMT, r2bw(), rres_has_ready_tasks(), RRES_PARANOID, rres_update_current_bandwidth(), sched_time, U_LUB2, and U_tot.

Referenced by qos_func_define(), and test_rres_init_module().

static void rres_set_weight	(	server_t *	srv,
		unsigned int	weight
	)			`[inline, static]`

Set the user-supplied server weight, that may be used by some scheduling policies (i.e., shrub).

Definition at line 84 of file rres_server.h.

References server_t::weight.

Referenced by qos_func_define().

void rres_stop ( server_t * srv )

Stop all tasks handled by the server.

The rotation may be disabled by setting the srv->forbid_reorder flag. This is useful while iterating over servers, e.g. while detaching all servers or similar.