This repository has been archived on 2023-08-20. You can view files and clone it, but cannot push or open issues or pull requests.
yap-6.3/OPTYap/or.scheduler.c
2011-03-29 18:19:18 +01:00

660 lines
22 KiB
C

/************************************************************************
** **
** The YapTab/YapOr/OPTYap systems **
** **
** YapTab extends the Yap Prolog engine to support sequential tabling **
** YapOr extends the Yap Prolog engine to support or-parallelism **
** OPTYap extends the Yap Prolog engine to support or-parallel tabling **
** **
** **
** Yap Prolog was developed at University of Porto, Portugal **
** **
************************************************************************/
/* ------------------ **
** Includes **
** ------------------ */
#include "Yap.h"
#ifdef YAPOR
#include "Yatom.h"
#include "YapHeap.h"
#include "or.macros.h"
#ifdef TABLING
#include "tab.macros.h"
#endif /* TABLING */
/* ------------------------------------- **
** Local functions declaration **
** ------------------------------------- */
static int move_up_one_node(or_fr_ptr nearest_livenode);
static int get_work_below(void);
static int get_work_above(void);
static int find_a_better_position(void);
static int search_for_hidden_shared_work(bitmap stable_busy);
/* ----------------------- **
** Local inlines **
** ----------------------- */
STD_PROTO(static inline void PUT_NO_WORK_IN_UPPER_NODES, (void));
STD_PROTO(static inline void PUT_IDLE, (int));
STD_PROTO(static inline void PUT_BUSY, (int));
STD_PROTO(static inline void PUT_IN_ROOT_NODE, (int));
STD_PROTO(static inline void PUT_OUT_ROOT_NODE, (int));
STD_PROTO(static inline void move_up_to_prune_request, (void));
static inline
void PUT_NO_WORK_IN_UPPER_NODES(void) {
CACHE_REGS
or_fr_ptr current_node, nearest_livenode;
current_node = LOCAL_top_or_fr;
while ((nearest_livenode = OrFr_nearest_livenode(current_node))) {
OrFr_nearest_livenode(current_node) = NULL;
current_node = nearest_livenode;
}
return;
}
static inline
void PUT_IDLE(int worker_num) {
LOCK(Yap_locks_bm_idle_workers);
BITMAP_insert(Yap_bm_idle_workers, worker_num);
UNLOCK(Yap_locks_bm_idle_workers);
return;
}
static inline
void PUT_BUSY(int worker_num) {
LOCK(Yap_locks_bm_idle_workers);
BITMAP_delete(Yap_bm_idle_workers, worker_num);
UNLOCK(Yap_locks_bm_idle_workers);
return;
}
static inline
void PUT_IN_ROOT_NODE(int worker_num) {
LOCK(Yap_locks_bm_root_cp_workers);
BITMAP_insert(Yap_bm_root_cp_workers, worker_num);
UNLOCK(Yap_locks_bm_root_cp_workers);
return;
}
static inline
void PUT_OUT_ROOT_NODE(int worker_num) {
LOCK(Yap_locks_bm_root_cp_workers);
BITMAP_delete(Yap_bm_root_cp_workers, worker_num);
UNLOCK(Yap_locks_bm_root_cp_workers);
return;
}
static inline
void move_up_to_prune_request(void) {
CACHE_REGS
YAPOR_ERROR_CHECKING(move_up_to_prune_request, EQUAL_OR_YOUNGER_CP(Get_LOCAL_prune_request(), Get_LOCAL_top_cp()));
do {
LOCK_OR_FRAME(LOCAL_top_or_fr);
if (BITMAP_alone(OrFr_members(LOCAL_top_or_fr), worker_id)) {
#ifdef TABLING
if (OrFr_suspensions(LOCAL_top_or_fr) || OrFr_owners(LOCAL_top_or_fr) != 1)
pruning_over_tabling_data_structures();
#endif /* TABLING */
CUT_free_solution_frames(OrFr_qg_solutions(LOCAL_top_or_fr));
#ifdef TABLING_INNER_CUTS
CUT_free_tg_solution_frames(OrFr_tg_solutions(LOCAL_top_or_fr));
#endif /* TABLING_INNER_CUTS */
FREE_OR_FRAME(LOCAL_top_or_fr);
} else {
BITMAP_delete(OrFr_members(LOCAL_top_or_fr), worker_id);
#ifdef TABLING
OrFr_owners(LOCAL_top_or_fr)--;
#endif /* TABLING */
UNLOCK_OR_FRAME(LOCAL_top_or_fr);
}
SCH_update_local_or_tops();
} while (Get_LOCAL_top_cp() != Get_LOCAL_prune_request());
CUT_reset_prune_request();
#ifdef TABLING
Set_LOCAL_top_cp_on_stack( Get_LOCAL_top_cp());
abolish_incomplete_subgoals(Get_LOCAL_top_cp() - 1); /* do not include LOCAL_top_cp */
#endif /* TABLIG */
return;
}
/* -------------------------- **
** Global functions **
** -------------------------- */
int get_work(void) {
CACHE_REGS
int counter;
bitmap stable_busy;
yamop *alt_with_work;
or_fr_ptr or_fr_with_work, or_fr_to_move_to;
#ifdef TABLING
choiceptr leader_node = DepFr_leader_cp(LOCAL_top_dep_fr);
#endif /* TABLING */
/* reset local load */
LOCAL_load = 0;
/* check for prune request */
if (Get_LOCAL_prune_request())
move_up_to_prune_request();
/* find nearest node with available work */
or_fr_with_work = LOCAL_top_or_fr;
do {
or_fr_with_work = OrFr_nearest_livenode(or_fr_with_work);
if (or_fr_with_work == NULL)
break;
alt_with_work = OrFr_alternative(or_fr_with_work);
} while (alt_with_work == NULL || YAMOP_SEQ(alt_with_work));
#ifndef TABLING
/* wait for incomplete installations */
while (LOCAL_reply_signal != worker_ready);
#endif /* TABLING */
if (or_fr_with_work) {
/* move up to the nearest node with available work */
#ifdef TABLING
if (leader_node && YOUNGER_CP(leader_node, GetOrFr_node(or_fr_with_work)))
/* there is a leader node before the nearest node with work */
or_fr_to_move_to = leader_node->cp_or_fr;
else
#endif /* TABLING */
or_fr_to_move_to = or_fr_with_work;
do {
if (! move_up_one_node(or_fr_with_work))
break;
} while (LOCAL_top_or_fr != or_fr_to_move_to);
return TRUE;
}
/* no nodes with available work */
PUT_NO_WORK_IN_UPPER_NODES();
#ifdef TABLING
if (leader_node) {
/* there is a leader node */
or_fr_to_move_to = leader_node->cp_or_fr;;
do {
if (! move_up_one_node(NULL))
break;
} while (LOCAL_top_or_fr != or_fr_to_move_to);
return TRUE;
}
#endif /* TABLING */
#ifdef TABLING_INNER_CUTS
if (LOCAL_pruning_scope) {
PUT_OUT_PRUNING(worker_id);
LOCAL_pruning_scope = NULL;
}
#endif /* TABLING_INNER_CUTS */
PUT_OUT_ROOT_NODE(worker_id);
LOCK_WORKER(worker_id);
PUT_IDLE(worker_id);
UNLOCK_WORKER(worker_id);
SCH_refuse_share_request_if_any();
counter = 0;
BITMAP_difference(stable_busy, OrFr_members(LOCAL_top_or_fr), Yap_bm_idle_workers);
while (1) {
while (BITMAP_subset(Yap_bm_idle_workers, OrFr_members(LOCAL_top_or_fr)) &&
Get_LOCAL_top_cp() != Get_Yap_root_cp()) {
/* no busy workers here and below */
if (! move_up_one_node(NULL)) {
PUT_BUSY(worker_id);
return TRUE;
}
}
if (Get_LOCAL_top_cp() == Get_Yap_root_cp()) {
if (! BITMAP_member(Yap_bm_root_cp_workers, worker_id))
PUT_IN_ROOT_NODE(worker_id);
if (BITMAP_same(Yap_bm_idle_workers, Yap_bm_root_cp_workers) &&
BITMAP_same(Yap_bm_idle_workers, Yap_bm_present_workers)) {
/* All workers are idle in root choicepoint. Execution
must finish as there is no available computation. */
return FALSE;
}
}
if (get_work_below()) {
PUT_BUSY(worker_id);
return TRUE;
}
if (get_work_above()) {
PUT_BUSY(worker_id);
return TRUE;
}
if (find_a_better_position()) {
PUT_BUSY(worker_id);
return TRUE;
}
if (++counter == Yap_scheduler_loop) {
if (search_for_hidden_shared_work(stable_busy)) {
PUT_BUSY(worker_id);
return TRUE;
}
counter = 0;
BITMAP_difference(stable_busy, OrFr_members(LOCAL_top_or_fr), Yap_bm_idle_workers);
} else {
BITMAP_minus(stable_busy, Yap_bm_idle_workers);
}
}
}
/* ------------------------- **
** Local functions **
** ------------------------- */
static
int move_up_one_node(or_fr_ptr nearest_livenode) {
CACHE_REGS
YAPOR_ERROR_CHECKING(move_up_one_node, Get_LOCAL_prune_request() && EQUAL_OR_YOUNGER_CP(Get_LOCAL_prune_request(), Get_LOCAL_top_cp()));
LOCK_OR_FRAME(LOCAL_top_or_fr);
/* last worker in a sequential choicepoint ? */
if (OrFr_alternative(LOCAL_top_or_fr)
&& YAMOP_SEQ(OrFr_alternative(LOCAL_top_or_fr))
&& BITMAP_alone(OrFr_members(LOCAL_top_or_fr), worker_id)) {
UNLOCK_OR_FRAME(LOCAL_top_or_fr);
return FALSE;
}
/* pending prune ? */
if (Get_OrFr_pend_prune_cp(LOCAL_top_or_fr)
&& ! Get_LOCAL_prune_request()
&& CUT_last_worker_left_pending_prune(LOCAL_top_or_fr)) {
#ifdef TABLING
choiceptr aux_cp = Get_LOCAL_top_cp();
#endif /* TABLIG */
choiceptr prune_cp = Get_OrFr_pend_prune_cp(LOCAL_top_or_fr);
Set_OrFr_pend_prune_cp(LOCAL_top_or_fr, NULL);
BRANCH(worker_id, OrFr_depth(LOCAL_top_or_fr)) = OrFr_pend_prune_ltt(LOCAL_top_or_fr);
UNLOCK_OR_FRAME(LOCAL_top_or_fr);
prune_shared_branch(prune_cp);
#ifdef TABLING
while (YOUNGER_CP(aux_cp->cp_b, Get_LOCAL_top_cp()))
aux_cp = aux_cp->cp_b;
abolish_incomplete_subgoals(aux_cp);
#endif /* TABLIG */
return FALSE;
}
OPTYAP_ERROR_CHECKING(move_up_one_node, B_FZ != DepFr_cons_cp(LOCAL_top_dep_fr));
OPTYAP_ERROR_CHECKING(move_up_one_node, LOCAL_top_susp_or_fr && EQUAL_OR_YOUNGER_CP(Get_LOCAL_top_cp(), B_FZ) && YOUNGER_CP(GetOrFr_node(LOCAL_top_susp_or_fr), Get_LOCAL_top_cp()));
OPTYAP_ERROR_CHECKING(move_up_one_node, LOCAL_top_susp_or_fr && YOUNGER_CP(B_FZ, Get_LOCAL_top_cp()) && YOUNGER_CP(GetOrFr_node(LOCAL_top_susp_or_fr), B_FZ));
#ifdef TABLING
/* frozen stacks on branch ? */
if (YOUNGER_CP(B_FZ, Get_LOCAL_top_cp())) {
if (nearest_livenode)
OrFr_nearest_livenode(LOCAL_top_or_fr) = nearest_livenode;
BITMAP_delete(OrFr_members(LOCAL_top_or_fr), worker_id);
if (BITMAP_empty(OrFr_members(LOCAL_top_or_fr))) {
if (frame_with_suspensions_not_collected(LOCAL_top_or_fr)) {
collect_suspension_frames(LOCAL_top_or_fr);
}
#ifdef TABLING_INNER_CUTS
if (OrFr_tg_solutions(LOCAL_top_or_fr)) {
tg_sol_fr_ptr tg_solutions;
or_fr_ptr leftmost_until;
tg_solutions = OrFr_tg_solutions(LOCAL_top_or_fr);
leftmost_until = CUT_leftmost_until(LOCAL_top_or_fr, OrFr_depth(TgSolFr_gen_cp(tg_solutions)->cp_or_fr));
OrFr_tg_solutions(LOCAL_top_or_fr) = NULL;
UNLOCK_OR_FRAME(LOCAL_top_or_fr);
if (leftmost_until) {
LOCK_OR_FRAME(leftmost_until);
tg_solutions = CUT_store_tg_answers(leftmost_until, tg_solutions,
BRANCH_LTT(worker_id, OrFr_depth(leftmost_until)));
UNLOCK_OR_FRAME(leftmost_until);
}
CUT_validate_tg_answers(tg_solutions);
goto update_local_tops1;
}
#endif /* TABLING_INNER_CUTS */
}
UNLOCK_OR_FRAME(LOCAL_top_or_fr);
#ifdef TABLING_INNER_CUTS
update_local_tops1:
#endif /* TABLING_INNER_CUTS */
SCH_update_local_or_tops();
if (Get_LOCAL_prune_request())
pruning_over_tabling_data_structures();
return TRUE;
}
/* suspension frames to resume ? */
if (OrFr_suspensions(LOCAL_top_or_fr)) {
susp_fr_ptr resume_fr;
#ifdef TIMESTAMP_CHECK
resume_fr = suspension_frame_to_resume(LOCAL_top_or_fr, ++Yap_time_stamp);
#else
resume_fr = suspension_frame_to_resume(LOCAL_top_or_fr);
#endif /* TIMESTAMP_CHECK */
if (resume_fr) {
if (LOCAL_top_susp_or_fr == LOCAL_top_or_fr && OrFr_suspensions(LOCAL_top_or_fr) == NULL) {
LOCAL_top_susp_or_fr = OrFr_nearest_suspnode(LOCAL_top_or_fr);
OrFr_nearest_suspnode(LOCAL_top_or_fr) = LOCAL_top_or_fr;
}
UNLOCK_OR_FRAME(LOCAL_top_or_fr);
unbind_variables(TR, Get_LOCAL_top_cp()->cp_tr);
resume_suspension_frame(resume_fr, LOCAL_top_or_fr);
return FALSE;
}
if (LOCAL_top_susp_or_fr == LOCAL_top_or_fr) {
LOCAL_top_susp_or_fr = OrFr_nearest_suspnode(LOCAL_top_or_fr);
OrFr_nearest_suspnode(LOCAL_top_or_fr) = NULL;
}
} else if (LOCAL_top_susp_or_fr == LOCAL_top_or_fr) {
LOCAL_top_susp_or_fr = OrFr_nearest_suspnode(LOCAL_top_or_fr);
OrFr_nearest_suspnode(LOCAL_top_or_fr) = LOCAL_top_or_fr;
}
/* top node frozen ? */
if (B_FZ == Get_LOCAL_top_cp()) {
if (nearest_livenode)
OrFr_nearest_livenode(LOCAL_top_or_fr) = nearest_livenode;
BITMAP_delete(OrFr_members(LOCAL_top_or_fr), worker_id);
#ifdef TABLING_INNER_CUTS
if (BITMAP_empty(OrFr_members(LOCAL_top_or_fr))) {
#endif /* TABLING_INNER_CUTS */
if (OrFr_suspensions(LOCAL_top_or_fr) && OrFr_owners(LOCAL_top_or_fr) == 1) {
complete_suspension_frames(LOCAL_top_or_fr);
}
#ifdef TABLING_INNER_CUTS
if (OrFr_tg_solutions(LOCAL_top_or_fr)) {
tg_sol_fr_ptr tg_solutions;
or_fr_ptr leftmost_until;
tg_solutions = OrFr_tg_solutions(LOCAL_top_or_fr);
leftmost_until = CUT_leftmost_until(LOCAL_top_or_fr, OrFr_depth(TgSolFr_gen_cp(tg_solutions)->cp_or_fr));
OrFr_tg_solutions(LOCAL_top_or_fr) = NULL;
UNLOCK_OR_FRAME(LOCAL_top_or_fr);
if (leftmost_until) {
LOCK_OR_FRAME(leftmost_until);
tg_solutions = CUT_store_tg_answers(leftmost_until, tg_solutions,
BRANCH_LTT(worker_id, OrFr_depth(leftmost_until)));
UNLOCK_OR_FRAME(leftmost_until);
}
CUT_validate_tg_answers(tg_solutions);
goto update_local_tops2;
}
}
#endif /* TABLING_INNER_CUTS */
UNLOCK_OR_FRAME(LOCAL_top_or_fr);
#ifdef TABLING_INNER_CUTS
update_local_tops2:
#endif /* TABLING_INNER_CUTS */
SCH_update_local_or_tops();
if (Get_LOCAL_prune_request())
pruning_over_tabling_data_structures();
return TRUE;
}
OPTYAP_ERROR_CHECKING(move_up_one_node, OrFr_alternative(LOCAL_top_or_fr) && ! YAMOP_SEQ(OrFr_alternative(LOCAL_top_or_fr)));
OPTYAP_ERROR_CHECKING(move_up_one_node, Get_LOCAL_top_cp() == DepFr_cons_cp(LOCAL_top_dep_fr));
OPTYAP_ERROR_CHECKING(move_up_one_node, Get_LOCAL_top_cp() != Get_LOCAL_top_cp_on_stack());
/* no frozen nodes */
Set_LOCAL_top_cp_on_stack(GetOrFr_node(OrFr_next_on_stack(LOCAL_top_or_fr)));
/* no more owners ? */
if (OrFr_owners(LOCAL_top_or_fr) == 1) {
if (OrFr_suspensions(LOCAL_top_or_fr)) {
complete_suspension_frames(LOCAL_top_or_fr);
}
if (LOCAL_top_sg_fr && Get_LOCAL_top_cp() == SgFr_gen_cp(LOCAL_top_sg_fr)) {
mark_as_completed(LOCAL_top_sg_fr);
LOCAL_top_sg_fr = SgFr_next(LOCAL_top_sg_fr);
}
#else
/* last member worker in node ? */
if (BITMAP_alone(OrFr_members(LOCAL_top_or_fr), worker_id)) {
#endif /* TABLING */
if (Get_LOCAL_prune_request()) {
CUT_free_solution_frames(OrFr_qg_solutions(LOCAL_top_or_fr));
#ifdef TABLING_INNER_CUTS
CUT_free_tg_solution_frames(OrFr_tg_solutions(LOCAL_top_or_fr));
#endif /* TABLING_INNER_CUTS */
FREE_OR_FRAME(LOCAL_top_or_fr);
SCH_update_local_or_tops();
CUT_reset_prune_request();
} else {
qg_sol_fr_ptr qg_solutions = OrFr_qg_solutions(LOCAL_top_or_fr);
#ifdef TABLING_INNER_CUTS
tg_sol_fr_ptr tg_solutions = OrFr_tg_solutions(LOCAL_top_or_fr);
#endif /* TABLING_INNER_CUTS */
FREE_OR_FRAME(LOCAL_top_or_fr);
SCH_update_local_or_tops();
CUT_reset_prune_request();
#ifdef TABLING_INNER_CUTS
if (qg_solutions || tg_solutions) {
or_fr_ptr leftmost_or_fr;
if (qg_solutions)
CUT_join_answers_in_an_unique_frame(qg_solutions);
leftmost_or_fr = CUT_leftmost_or_frame();
LOCK_OR_FRAME(leftmost_or_fr);
if (qg_solutions)
CUT_store_answers(leftmost_or_fr, qg_solutions);
if (tg_solutions)
tg_solutions = CUT_store_tg_answers(leftmost_or_fr, tg_solutions,
BRANCH_LTT(worker_id, OrFr_depth(leftmost_or_fr)));
UNLOCK_OR_FRAME(leftmost_or_fr);
CUT_validate_tg_answers(tg_solutions);
}
#else
if (qg_solutions) {
or_fr_ptr leftmost_or_fr;
CUT_join_answers_in_an_unique_frame(qg_solutions);
leftmost_or_fr = CUT_leftmost_or_frame();
LOCK_OR_FRAME(leftmost_or_fr);
CUT_store_answers(leftmost_or_fr, qg_solutions);
UNLOCK_OR_FRAME(leftmost_or_fr);
}
#endif /* TABLING_INNER_CUTS */
}
return TRUE;
}
/* more owners */
if (nearest_livenode)
OrFr_nearest_livenode(LOCAL_top_or_fr) = nearest_livenode;
BITMAP_delete(OrFr_members(LOCAL_top_or_fr), worker_id);
#ifdef TABLING
OrFr_owners(LOCAL_top_or_fr)--;
if (BITMAP_empty(OrFr_members(LOCAL_top_or_fr))) {
#ifdef TABLING_INNER_CUTS
if (OrFr_tg_solutions(LOCAL_top_or_fr)) {
tg_sol_fr_ptr tg_solutions;
or_fr_ptr leftmost_until;
tg_solutions = OrFr_tg_solutions(LOCAL_top_or_fr);
leftmost_until = CUT_leftmost_until(LOCAL_top_or_fr, OrFr_depth(TgSolFr_gen_cp(tg_solutions)->cp_or_fr));
if (Get_LOCAL_prune_request())
pruning_over_tabling_data_structures();
OrFr_tg_solutions(LOCAL_top_or_fr) = NULL;
UNLOCK_OR_FRAME(LOCAL_top_or_fr);
if (leftmost_until) {
LOCK_OR_FRAME(leftmost_until);
tg_solutions = CUT_store_tg_answers(leftmost_until, tg_solutions,
BRANCH_LTT(worker_id, OrFr_depth(leftmost_until)));
UNLOCK_OR_FRAME(leftmost_until);
}
CUT_validate_tg_answers(tg_solutions);
goto update_local_tops3;
}
#endif /* TABLING_INNER_CUTS */
if (Get_LOCAL_prune_request())
pruning_over_tabling_data_structures();
}
#endif /* TABLING */
UNLOCK_OR_FRAME(LOCAL_top_or_fr);
#ifdef TABLING
#ifdef TABLING_INNER_CUTS
update_local_tops3:
#endif /* TABLING_INNER_CUTS */
if (LOCAL_top_sg_fr && Get_LOCAL_top_cp() == SgFr_gen_cp(LOCAL_top_sg_fr)) {
LOCAL_top_sg_fr = SgFr_next(LOCAL_top_sg_fr);
}
#endif /* TABLING */
SCH_update_local_or_tops();
CUT_reset_prune_request();
return TRUE;
}
static
int get_work_below(void){
CACHE_REGS
int i, worker_p, big_load;
bitmap busy_below, idle_below;
worker_p = -1;
big_load = Yap_delayed_release_load ;
BITMAP_difference(busy_below, OrFr_members(LOCAL_top_or_fr), Yap_bm_idle_workers);
BITMAP_difference(idle_below, OrFr_members(LOCAL_top_or_fr), busy_below);
BITMAP_delete(idle_below, worker_id);
for (i = 0; i < Yap_number_workers; i++) {
if (BITMAP_member(idle_below ,i) && YOUNGER_CP(REMOTE_top_cp(i), Get_LOCAL_top_cp()))
BITMAP_minus(busy_below, OrFr_members(REMOTE_top_or_fr(i)));
}
if (BITMAP_empty(busy_below))
return FALSE;
/* choose the worker with highest load */
for (i = 0 ; i < Yap_number_workers; i++) {
if (BITMAP_member(busy_below ,i) && REMOTE_load(i) > big_load) {
worker_p = i;
big_load = REMOTE_load(i);
}
}
if (worker_p == -1)
return FALSE;
return (q_share_work(worker_p));
}
static
int get_work_above(void){
CACHE_REGS
int i, worker_p, big_load;
bitmap visible_busy_above, visible_idle_above;
worker_p = -1;
big_load = Yap_delayed_release_load ;
BITMAP_difference(visible_busy_above, Yap_bm_present_workers, OrFr_members(LOCAL_top_or_fr));
BITMAP_minus(visible_busy_above, Yap_bm_invisible_workers);
BITMAP_copy(visible_idle_above, visible_busy_above);
BITMAP_minus(visible_busy_above, Yap_bm_idle_workers);
BITMAP_and(visible_idle_above, Yap_bm_idle_workers);
BITMAP_insert(visible_busy_above, worker_id);
for (i = 0 ; i < Yap_number_workers; i++) {
if (BITMAP_member(visible_idle_above, i))
BITMAP_minus(visible_busy_above, OrFr_members(REMOTE_top_or_fr(i)));
}
if (!BITMAP_member(visible_busy_above, worker_id) || BITMAP_alone(visible_busy_above, worker_id))
return FALSE;
BITMAP_delete(visible_busy_above, worker_id);
/* choose the worker with higher load */
for (i = 0; i < Yap_number_workers; i++) {
if (BITMAP_member(visible_busy_above ,i) && REMOTE_load(i) > big_load) {
worker_p = i;
big_load = REMOTE_load(i);
}
}
if (worker_p == -1)
return FALSE;
/* put workers invisibles */
LOCK(Yap_locks_bm_invisible_workers);
if (BITMAP_member(Yap_bm_invisible_workers, worker_p)) {
UNLOCK(Yap_locks_bm_invisible_workers);
return FALSE;
}
BITMAP_insert(Yap_bm_invisible_workers, worker_id);
BITMAP_insert(Yap_bm_invisible_workers, worker_p);
UNLOCK(Yap_locks_bm_invisible_workers);
/* move up to cp with worker_p */
do {
if (! move_up_one_node(NULL)) {
return TRUE;
}
} while (! BITMAP_member(OrFr_members(LOCAL_top_or_fr), worker_p));
/* put workers visibles */
LOCK(Yap_locks_bm_invisible_workers);
BITMAP_delete(Yap_bm_invisible_workers, worker_id);
BITMAP_delete(Yap_bm_invisible_workers, worker_p);
UNLOCK(Yap_locks_bm_invisible_workers);
return (q_share_work(worker_p));
}
static
int find_a_better_position(void){
CACHE_REGS
int i;
bitmap busy_above, idle_above;
BITMAP_difference(busy_above, Yap_bm_present_workers, OrFr_members(LOCAL_top_or_fr));
BITMAP_copy(idle_above, busy_above);
BITMAP_minus(busy_above, Yap_bm_idle_workers);
BITMAP_and(idle_above, Yap_bm_idle_workers);
for (i = 0; i < Yap_number_workers; i++) {
if (BITMAP_member(idle_above, i)) {
if (BITMAP_empty(busy_above))
break;
if (BITMAP_member(OrFr_members(REMOTE_top_or_fr(i)), worker_id))
BITMAP_clear(busy_above);
BITMAP_minus(busy_above, OrFr_members(REMOTE_top_or_fr(i)));
}
}
if (BITMAP_empty(busy_above))
return FALSE;
/* move up to cp with all workers of bitmap busy_above */
do {
if (! move_up_one_node(NULL)) {
return TRUE;
}
} while (! BITMAP_subset(OrFr_members(LOCAL_top_or_fr), busy_above));
return FALSE;
}
static
int search_for_hidden_shared_work(bitmap stable_busy){
CACHE_REGS
int i;
bitmap invisible_work, idle_below;
BITMAP_intersection(invisible_work, stable_busy, Yap_bm_requestable_workers);
BITMAP_intersection(idle_below, OrFr_members(LOCAL_top_or_fr), Yap_bm_idle_workers);
BITMAP_delete(idle_below, worker_id);
for (i = 0; i < Yap_number_workers; i++) {
if (BITMAP_member(idle_below ,i) && YOUNGER_CP(REMOTE_top_cp(i), Get_LOCAL_top_cp()))
BITMAP_minus(invisible_work, OrFr_members(REMOTE_top_or_fr(i)));
}
if (BITMAP_empty(invisible_work))
return FALSE;
/* choose the first available worker */
for (i = 0; i < Yap_number_workers; i++ ) {
if (BITMAP_member(invisible_work ,i))
break;
}
return (q_share_work(i));
}
#endif /* YAPOR */