kmp_barrier.cpp
/*
* kmp_barrier.cpp
*/
//===----------------------------------------------------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is dual licensed under the MIT and the University of Illinois Open
// Source Licenses. See LICENSE.txt for details.
//
//===----------------------------------------------------------------------===//
#include "kmp.h"
#include "kmp_wait_release.h"
#include "kmp_itt.h"
#include "kmp_os.h"
#include "kmp_stats.h"
#if OMPT_SUPPORT
#include "ompt-specific.h"
#endif
#if KMP_MIC
#include <immintrin.h>
#define USE_NGO_STORES 1
#endif // KMP_MIC
#include "tsan_annotations.h"
#if KMP_MIC && USE_NGO_STORES
// ICV copying
#define ngo_load(src) __m512d Vt = _mm512_load_pd((void *)(src))
#define ngo_store_icvs(dst, src) _mm512_storenrngo_pd((void *)(dst), Vt)
#define ngo_store_go(dst, src) _mm512_storenrngo_pd((void *)(dst), Vt)
#define ngo_sync() __asm__ volatile("lock; addl $0,0(%%rsp)" ::: "memory")
#else
#define ngo_load(src) ((void)0)
#define ngo_store_icvs(dst, src) copy_icvs((dst), (src))
#define ngo_store_go(dst, src) KMP_MEMCPY((dst), (src), CACHE_LINE)
#define ngo_sync() ((void)0)
#endif /* KMP_MIC && USE_NGO_STORES */
void __kmp_print_structure(void); // Forward declaration
// ---------------------------- Barrier Algorithms ----------------------------
// Linear Barrier
static void __kmp_linear_barrier_gather(
enum barrier_type bt, kmp_info_t *this_thr, int gtid, int tid,
void (*reduce)(void *, void *) USE_ITT_BUILD_ARG(void *itt_sync_obj)) {
KMP_TIME_DEVELOPER_PARTITIONED_BLOCK(KMP_linear_gather);
kmp_team_t *team = this_thr->th.th_team;
kmp_bstate_t *thr_bar = &this_thr->th.th_bar[bt].bb;
kmp_info_t **other_threads = team->t.t_threads;
KA_TRACE(
20,
("__kmp_linear_barrier_gather: T#%d(%d:%d) enter for barrier type %d\n",
gtid, team->t.t_id, tid, bt));
KMP_DEBUG_ASSERT(this_thr == other_threads[this_thr->th.th_info.ds.ds_tid]);
#if USE_ITT_BUILD && USE_ITT_NOTIFY
// Barrier imbalance - save arrive time to the thread
if (__kmp_forkjoin_frames_mode == 3 || __kmp_forkjoin_frames_mode == 2) {
this_thr->th.th_bar_arrive_time = this_thr->th.th_bar_min_time =
__itt_get_timestamp();
}
#endif
// We now perform a linear reduction to signal that all of the threads have
// arrived.
if (!KMP_MASTER_TID(tid)) {
KA_TRACE(20,
("__kmp_linear_barrier_gather: T#%d(%d:%d) releasing T#%d(%d:%d)"
"arrived(%p): %llu => %llu\n",
gtid, team->t.t_id, tid, __kmp_gtid_from_tid(0, team),
team->t.t_id, 0, &thr_bar->b_arrived, thr_bar->b_arrived,
thr_bar->b_arrived + KMP_BARRIER_STATE_BUMP));
// Mark arrival to master thread
/* After performing this write, a worker thread may not assume that the team
is valid any more - it could be deallocated by the master thread at any
time. */
ANNOTATE_BARRIER_BEGIN(this_thr);
kmp_flag_64 flag(&thr_bar->b_arrived, other_threads[0]);
flag.release();
} else {
kmp_balign_team_t *team_bar = &team->t.t_bar[bt];
int nproc = this_thr->th.th_team_nproc;
int i;
// Don't have to worry about sleep bit here or atomic since team setting
kmp_uint64 new_state = team_bar->b_arrived + KMP_BARRIER_STATE_BUMP;
// Collect all the worker team member threads.
for (i = 1; i < nproc; ++i) {
#if KMP_CACHE_MANAGE
// Prefetch next thread's arrived count
if (i + 1 < nproc)
KMP_CACHE_PREFETCH(&other_threads[i + 1]->th.th_bar[bt].bb.b_arrived);
#endif /* KMP_CACHE_MANAGE */
KA_TRACE(20, ("__kmp_linear_barrier_gather: T#%d(%d:%d) wait T#%d(%d:%d) "
"arrived(%p) == %llu\n",
gtid, team->t.t_id, tid, __kmp_gtid_from_tid(i, team),
team->t.t_id, i,
&other_threads[i]->th.th_bar[bt].bb.b_arrived, new_state));
// Wait for worker thread to arrive
kmp_flag_64 flag(&other_threads[i]->th.th_bar[bt].bb.b_arrived,
new_state);
flag.wait(this_thr, FALSE USE_ITT_BUILD_ARG(itt_sync_obj));
ANNOTATE_BARRIER_END(other_threads[i]);
#if USE_ITT_BUILD && USE_ITT_NOTIFY
// Barrier imbalance - write min of the thread time and the other thread
// time to the thread.
if (__kmp_forkjoin_frames_mode == 2) {
this_thr->th.th_bar_min_time = KMP_MIN(
this_thr->th.th_bar_min_time, other_threads[i]->th.th_bar_min_time);
}
#endif
if (reduce) {
KA_TRACE(100,
("__kmp_linear_barrier_gather: T#%d(%d:%d) += T#%d(%d:%d)\n",
gtid, team->t.t_id, tid, __kmp_gtid_from_tid(i, team),
team->t.t_id, i));
ANNOTATE_REDUCE_AFTER(reduce);
(*reduce)(this_thr->th.th_local.reduce_data,
other_threads[i]->th.th_local.reduce_data);
ANNOTATE_REDUCE_BEFORE(reduce);
ANNOTATE_REDUCE_BEFORE(&team->t.t_bar);
}
}
// Don't have to worry about sleep bit here or atomic since team setting
team_bar->b_arrived = new_state;
KA_TRACE(20, ("__kmp_linear_barrier_gather: T#%d(%d:%d) set team %d "
"arrived(%p) = %llu\n",
gtid, team->t.t_id, tid, team->t.t_id, &team_bar->b_arrived,
new_state));
}
KA_TRACE(
20,
("__kmp_linear_barrier_gather: T#%d(%d:%d) exit for barrier type %d\n",
gtid, team->t.t_id, tid, bt));
}
static void __kmp_linear_barrier_release(
enum barrier_type bt, kmp_info_t *this_thr, int gtid, int tid,
int propagate_icvs USE_ITT_BUILD_ARG(void *itt_sync_obj)) {
KMP_TIME_DEVELOPER_PARTITIONED_BLOCK(KMP_linear_release);
kmp_bstate_t *thr_bar = &this_thr->th.th_bar[bt].bb;
kmp_team_t *team;
if (KMP_MASTER_TID(tid)) {
unsigned int i;
kmp_uint32 nproc = this_thr->th.th_team_nproc;
kmp_info_t **other_threads;
team = __kmp_threads[gtid]->th.th_team;
KMP_DEBUG_ASSERT(team != NULL);
other_threads = team->t.t_threads;
KA_TRACE(20, ("__kmp_linear_barrier_release: T#%d(%d:%d) master enter for "
"barrier type %d\n",
gtid, team->t.t_id, tid, bt));
if (nproc > 1) {
#if KMP_BARRIER_ICV_PUSH
{
KMP_TIME_DEVELOPER_PARTITIONED_BLOCK(USER_icv_copy);
if (propagate_icvs) {
ngo_load(&team->t.t_implicit_task_taskdata[0].td_icvs);
for (i = 1; i < nproc; ++i) {
__kmp_init_implicit_task(team->t.t_ident, team->t.t_threads[i],
team, i, FALSE);
ngo_store_icvs(&team->t.t_implicit_task_taskdata[i].td_icvs,
&team->t.t_implicit_task_taskdata[0].td_icvs);
}
ngo_sync();
}
}
#endif // KMP_BARRIER_ICV_PUSH
// Now, release all of the worker threads
for (i = 1; i < nproc; ++i) {
#if KMP_CACHE_MANAGE
// Prefetch next thread's go flag
if (i + 1 < nproc)
KMP_CACHE_PREFETCH(&other_threads[i + 1]->th.th_bar[bt].bb.b_go);
#endif /* KMP_CACHE_MANAGE */
KA_TRACE(
20,
("__kmp_linear_barrier_release: T#%d(%d:%d) releasing T#%d(%d:%d) "
"go(%p): %u => %u\n",
gtid, team->t.t_id, tid, other_threads[i]->th.th_info.ds.ds_gtid,
team->t.t_id, i, &other_threads[i]->th.th_bar[bt].bb.b_go,
other_threads[i]->th.th_bar[bt].bb.b_go,
other_threads[i]->th.th_bar[bt].bb.b_go + KMP_BARRIER_STATE_BUMP));
ANNOTATE_BARRIER_BEGIN(other_threads[i]);
kmp_flag_64 flag(&other_threads[i]->th.th_bar[bt].bb.b_go,
other_threads[i]);
flag.release();
}
}
} else { // Wait for the MASTER thread to release us
KA_TRACE(20, ("__kmp_linear_barrier_release: T#%d wait go(%p) == %u\n",
gtid, &thr_bar->b_go, KMP_BARRIER_STATE_BUMP));
kmp_flag_64 flag(&thr_bar->b_go, KMP_BARRIER_STATE_BUMP);
flag.wait(this_thr, TRUE USE_ITT_BUILD_ARG(itt_sync_obj));
ANNOTATE_BARRIER_END(this_thr);
#if USE_ITT_BUILD && USE_ITT_NOTIFY
if ((__itt_sync_create_ptr && itt_sync_obj == NULL) || KMP_ITT_DEBUG) {
// In a fork barrier; cannot get the object reliably (or ITTNOTIFY is
// disabled)
itt_sync_obj = __kmp_itt_barrier_object(gtid, bs_forkjoin_barrier, 0, -1);
// Cancel wait on previous parallel region...
__kmp_itt_task_starting(itt_sync_obj);
if (bt == bs_forkjoin_barrier && TCR_4(__kmp_global.g.g_done))
return;
itt_sync_obj = __kmp_itt_barrier_object(gtid, bs_forkjoin_barrier);
if (itt_sync_obj != NULL)
// Call prepare as early as possible for "new" barrier
__kmp_itt_task_finished(itt_sync_obj);
} else
#endif /* USE_ITT_BUILD && USE_ITT_NOTIFY */
// Early exit for reaping threads releasing forkjoin barrier
if (bt == bs_forkjoin_barrier && TCR_4(__kmp_global.g.g_done))
return;
// The worker thread may now assume that the team is valid.
#ifdef KMP_DEBUG
tid = __kmp_tid_from_gtid(gtid);
team = __kmp_threads[gtid]->th.th_team;
#endif
KMP_DEBUG_ASSERT(team != NULL);
TCW_4(thr_bar->b_go, KMP_INIT_BARRIER_STATE);
KA_TRACE(20,
("__kmp_linear_barrier_release: T#%d(%d:%d) set go(%p) = %u\n",
gtid, team->t.t_id, tid, &thr_bar->b_go, KMP_INIT_BARRIER_STATE));
KMP_MB(); // Flush all pending memory write invalidates.
}
KA_TRACE(
20,
("__kmp_linear_barrier_release: T#%d(%d:%d) exit for barrier type %d\n",
gtid, team->t.t_id, tid, bt));
}
// Tree barrier
static void
__kmp_tree_barrier_gather(enum barrier_type bt, kmp_info_t *this_thr, int gtid,
int tid, void (*reduce)(void *, void *)
USE_ITT_BUILD_ARG(void *itt_sync_obj)) {
KMP_TIME_DEVELOPER_PARTITIONED_BLOCK(KMP_tree_gather);
kmp_team_t *team = this_thr->th.th_team;
kmp_bstate_t *thr_bar = &this_thr->th.th_bar[bt].bb;
kmp_info_t **other_threads = team->t.t_threads;
kmp_uint32 nproc = this_thr->th.th_team_nproc;
kmp_uint32 branch_bits = __kmp_barrier_gather_branch_bits[bt];
kmp_uint32 branch_factor = 1 << branch_bits;
kmp_uint32 child;
kmp_uint32 child_tid;
kmp_uint64 new_state;
KA_TRACE(
20, ("__kmp_tree_barrier_gather: T#%d(%d:%d) enter for barrier type %d\n",
gtid, team->t.t_id, tid, bt));
KMP_DEBUG_ASSERT(this_thr == other_threads[this_thr->th.th_info.ds.ds_tid]);
#if USE_ITT_BUILD && USE_ITT_NOTIFY
// Barrier imbalance - save arrive time to the thread
if (__kmp_forkjoin_frames_mode == 3 || __kmp_forkjoin_frames_mode == 2) {
this_thr->th.th_bar_arrive_time = this_thr->th.th_bar_min_time =
__itt_get_timestamp();
}
#endif
// Perform tree gather to wait until all threads have arrived; reduce any
// required data as we go
child_tid = (tid << branch_bits) + 1;
if (child_tid < nproc) {
// Parent threads wait for all their children to arrive
new_state = team->t.t_bar[bt].b_arrived + KMP_BARRIER_STATE_BUMP;
child = 1;
do {
kmp_info_t *child_thr = other_threads[child_tid];
kmp_bstate_t *child_bar = &child_thr->th.th_bar[bt].bb;
#if KMP_CACHE_MANAGE
// Prefetch next thread's arrived count
if (child + 1 <= branch_factor && child_tid + 1 < nproc)
KMP_CACHE_PREFETCH(
&other_threads[child_tid + 1]->th.th_bar[bt].bb.b_arrived);
#endif /* KMP_CACHE_MANAGE */
KA_TRACE(20,
("__kmp_tree_barrier_gather: T#%d(%d:%d) wait T#%d(%d:%u) "
"arrived(%p) == %llu\n",
gtid, team->t.t_id, tid, __kmp_gtid_from_tid(child_tid, team),
team->t.t_id, child_tid, &child_bar->b_arrived, new_state));
// Wait for child to arrive
kmp_flag_64 flag(&child_bar->b_arrived, new_state);
flag.wait(this_thr, FALSE USE_ITT_BUILD_ARG(itt_sync_obj));
ANNOTATE_BARRIER_END(child_thr);
#if USE_ITT_BUILD && USE_ITT_NOTIFY
// Barrier imbalance - write min of the thread time and a child time to
// the thread.
if (__kmp_forkjoin_frames_mode == 2) {
this_thr->th.th_bar_min_time = KMP_MIN(this_thr->th.th_bar_min_time,
child_thr->th.th_bar_min_time);
}
#endif
if (reduce) {
KA_TRACE(100,
("__kmp_tree_barrier_gather: T#%d(%d:%d) += T#%d(%d:%u)\n",
gtid, team->t.t_id, tid, __kmp_gtid_from_tid(child_tid, team),
team->t.t_id, child_tid));
ANNOTATE_REDUCE_AFTER(reduce);
(*reduce)(this_thr->th.th_local.reduce_data,
child_thr->th.th_local.reduce_data);
ANNOTATE_REDUCE_BEFORE(reduce);
ANNOTATE_REDUCE_BEFORE(&team->t.t_bar);
}
child++;
child_tid++;
} while (child <= branch_factor && child_tid < nproc);
}
if (!KMP_MASTER_TID(tid)) { // Worker threads
kmp_int32 parent_tid = (tid - 1) >> branch_bits;
KA_TRACE(20,
("__kmp_tree_barrier_gather: T#%d(%d:%d) releasing T#%d(%d:%d) "
"arrived(%p): %llu => %llu\n",
gtid, team->t.t_id, tid, __kmp_gtid_from_tid(parent_tid, team),
team->t.t_id, parent_tid, &thr_bar->b_arrived, thr_bar->b_arrived,
thr_bar->b_arrived + KMP_BARRIER_STATE_BUMP));
// Mark arrival to parent thread
/* After performing this write, a worker thread may not assume that the team
is valid any more - it could be deallocated by the master thread at any
time. */
ANNOTATE_BARRIER_BEGIN(this_thr);
kmp_flag_64 flag(&thr_bar->b_arrived, other_threads[parent_tid]);
flag.release();
} else {
// Need to update the team arrived pointer if we are the master thread
if (nproc > 1) // New value was already computed above
team->t.t_bar[bt].b_arrived = new_state;
else
team->t.t_bar[bt].b_arrived += KMP_BARRIER_STATE_BUMP;
KA_TRACE(20, ("__kmp_tree_barrier_gather: T#%d(%d:%d) set team %d "
"arrived(%p) = %llu\n",
gtid, team->t.t_id, tid, team->t.t_id,
&team->t.t_bar[bt].b_arrived, team->t.t_bar[bt].b_arrived));
}
KA_TRACE(20,
("__kmp_tree_barrier_gather: T#%d(%d:%d) exit for barrier type %d\n",
gtid, team->t.t_id, tid, bt));
}
static void __kmp_tree_barrier_release(
enum barrier_type bt, kmp_info_t *this_thr, int gtid, int tid,
int propagate_icvs USE_ITT_BUILD_ARG(void *itt_sync_obj)) {
KMP_TIME_DEVELOPER_PARTITIONED_BLOCK(KMP_tree_release);
kmp_team_t *team;
kmp_bstate_t *thr_bar = &this_thr->th.th_bar[bt].bb;
kmp_uint32 nproc;
kmp_uint32 branch_bits = __kmp_barrier_release_branch_bits[bt];
kmp_uint32 branch_factor = 1 << branch_bits;
kmp_uint32 child;
kmp_uint32 child_tid;
// Perform a tree release for all of the threads that have been gathered
if (!KMP_MASTER_TID(
tid)) { // Handle fork barrier workers who aren't part of a team yet
KA_TRACE(20, ("__kmp_tree_barrier_release: T#%d wait go(%p) == %u\n", gtid,
&thr_bar->b_go, KMP_BARRIER_STATE_BUMP));
// Wait for parent thread to release us
kmp_flag_64 flag(&thr_bar->b_go, KMP_BARRIER_STATE_BUMP);
flag.wait(this_thr, TRUE USE_ITT_BUILD_ARG(itt_sync_obj));
ANNOTATE_BARRIER_END(this_thr);
#if USE_ITT_BUILD && USE_ITT_NOTIFY
if ((__itt_sync_create_ptr && itt_sync_obj == NULL) || KMP_ITT_DEBUG) {
// In fork barrier where we could not get the object reliably (or
// ITTNOTIFY is disabled)
itt_sync_obj = __kmp_itt_barrier_object(gtid, bs_forkjoin_barrier, 0, -1);
// Cancel wait on previous parallel region...
__kmp_itt_task_starting(itt_sync_obj);
if (bt == bs_forkjoin_barrier && TCR_4(__kmp_global.g.g_done))
return;
itt_sync_obj = __kmp_itt_barrier_object(gtid, bs_forkjoin_barrier);
if (itt_sync_obj != NULL)
// Call prepare as early as possible for "new" barrier
__kmp_itt_task_finished(itt_sync_obj);
} else
#endif /* USE_ITT_BUILD && USE_ITT_NOTIFY */
// Early exit for reaping threads releasing forkjoin barrier
if (bt == bs_forkjoin_barrier && TCR_4(__kmp_global.g.g_done))
return;
// The worker thread may now assume that the team is valid.
team = __kmp_threads[gtid]->th.th_team;
KMP_DEBUG_ASSERT(team != NULL);
tid = __kmp_tid_from_gtid(gtid);
TCW_4(thr_bar->b_go, KMP_INIT_BARRIER_STATE);
KA_TRACE(20,
("__kmp_tree_barrier_release: T#%d(%d:%d) set go(%p) = %u\n", gtid,
team->t.t_id, tid, &thr_bar->b_go, KMP_INIT_BARRIER_STATE));
KMP_MB(); // Flush all pending memory write invalidates.
} else {
team = __kmp_threads[gtid]->th.th_team;
KMP_DEBUG_ASSERT(team != NULL);
KA_TRACE(20, ("__kmp_tree_barrier_release: T#%d(%d:%d) master enter for "
"barrier type %d\n",
gtid, team->t.t_id, tid, bt));
}
nproc = this_thr->th.th_team_nproc;
child_tid = (tid << branch_bits) + 1;
if (child_tid < nproc) {
kmp_info_t **other_threads = team->t.t_threads;
child = 1;
// Parent threads release all their children
do {
kmp_info_t *child_thr = other_threads[child_tid];
kmp_bstate_t *child_bar = &child_thr->th.th_bar[bt].bb;
#if KMP_CACHE_MANAGE
// Prefetch next thread's go count
if (child + 1 <= branch_factor && child_tid + 1 < nproc)
KMP_CACHE_PREFETCH(
&other_threads[child_tid + 1]->th.th_bar[bt].bb.b_go);
#endif /* KMP_CACHE_MANAGE */
#if KMP_BARRIER_ICV_PUSH
{
KMP_TIME_DEVELOPER_PARTITIONED_BLOCK(USER_icv_copy);
if (propagate_icvs) {
__kmp_init_implicit_task(team->t.t_ident,
team->t.t_threads[child_tid], team,
child_tid, FALSE);
copy_icvs(&team->t.t_implicit_task_taskdata[child_tid].td_icvs,
&team->t.t_implicit_task_taskdata[0].td_icvs);
}
}
#endif // KMP_BARRIER_ICV_PUSH
KA_TRACE(20,
("__kmp_tree_barrier_release: T#%d(%d:%d) releasing T#%d(%d:%u)"
"go(%p): %u => %u\n",
gtid, team->t.t_id, tid, __kmp_gtid_from_tid(child_tid, team),
team->t.t_id, child_tid, &child_bar->b_go, child_bar->b_go,
child_bar->b_go + KMP_BARRIER_STATE_BUMP));
// Release child from barrier
ANNOTATE_BARRIER_BEGIN(child_thr);
kmp_flag_64 flag(&child_bar->b_go, child_thr);
flag.release();
child++;
child_tid++;
} while (child <= branch_factor && child_tid < nproc);
}
KA_TRACE(
20, ("__kmp_tree_barrier_release: T#%d(%d:%d) exit for barrier type %d\n",
gtid, team->t.t_id, tid, bt));
}
// Hyper Barrier
static void
__kmp_hyper_barrier_gather(enum barrier_type bt, kmp_info_t *this_thr, int gtid,
int tid, void (*reduce)(void *, void *)
USE_ITT_BUILD_ARG(void *itt_sync_obj)) {
KMP_TIME_DEVELOPER_PARTITIONED_BLOCK(KMP_hyper_gather);
kmp_team_t *team = this_thr->th.th_team;
kmp_bstate_t *thr_bar = &this_thr->th.th_bar[bt].bb;
kmp_info_t **other_threads = team->t.t_threads;
kmp_uint64 new_state = KMP_BARRIER_UNUSED_STATE;
kmp_uint32 num_threads = this_thr->th.th_team_nproc;
kmp_uint32 branch_bits = __kmp_barrier_gather_branch_bits[bt];
kmp_uint32 branch_factor = 1 << branch_bits;
kmp_uint32 offset;
kmp_uint32 level;
KA_TRACE(
20,
("__kmp_hyper_barrier_gather: T#%d(%d:%d) enter for barrier type %d\n",
gtid, team->t.t_id, tid, bt));
KMP_DEBUG_ASSERT(this_thr == other_threads[this_thr->th.th_info.ds.ds_tid]);
#if USE_ITT_BUILD && USE_ITT_NOTIFY
// Barrier imbalance - save arrive time to the thread
if (__kmp_forkjoin_frames_mode == 3 || __kmp_forkjoin_frames_mode == 2) {
this_thr->th.th_bar_arrive_time = this_thr->th.th_bar_min_time =
__itt_get_timestamp();
}
#endif
/* Perform a hypercube-embedded tree gather to wait until all of the threads
have arrived, and reduce any required data as we go. */
kmp_flag_64 p_flag(&thr_bar->b_arrived);
for (level = 0, offset = 1; offset < num_threads;
level += branch_bits, offset <<= branch_bits) {
kmp_uint32 child;
kmp_uint32 child_tid;
if (((tid >> level) & (branch_factor - 1)) != 0) {
kmp_int32 parent_tid = tid & ~((1 << (level + branch_bits)) - 1);
KA_TRACE(20,
("__kmp_hyper_barrier_gather: T#%d(%d:%d) releasing T#%d(%d:%d) "
"arrived(%p): %llu => %llu\n",
gtid, team->t.t_id, tid, __kmp_gtid_from_tid(parent_tid, team),
team->t.t_id, parent_tid, &thr_bar->b_arrived,
thr_bar->b_arrived,
thr_bar->b_arrived + KMP_BARRIER_STATE_BUMP));
// Mark arrival to parent thread
/* After performing this write (in the last iteration of the enclosing for
loop), a worker thread may not assume that the team is valid any more
- it could be deallocated by the master thread at any time. */
ANNOTATE_BARRIER_BEGIN(this_thr);
p_flag.set_waiter(other_threads[parent_tid]);
p_flag.release();
break;
}
// Parent threads wait for children to arrive
if (new_state == KMP_BARRIER_UNUSED_STATE)
new_state = team->t.t_bar[bt].b_arrived + KMP_BARRIER_STATE_BUMP;
for (child = 1, child_tid = tid + (1 << level);
child < branch_factor && child_tid < num_threads;
child++, child_tid += (1 << level)) {
kmp_info_t *child_thr = other_threads[child_tid];
kmp_bstate_t *child_bar = &child_thr->th.th_bar[bt].bb;
#if KMP_CACHE_MANAGE
kmp_uint32 next_child_tid = child_tid + (1 << level);
// Prefetch next thread's arrived count
if (child + 1 < branch_factor && next_child_tid < num_threads)
KMP_CACHE_PREFETCH(
&other_threads[next_child_tid]->th.th_bar[bt].bb.b_arrived);
#endif /* KMP_CACHE_MANAGE */
KA_TRACE(20,
("__kmp_hyper_barrier_gather: T#%d(%d:%d) wait T#%d(%d:%u) "
"arrived(%p) == %llu\n",
gtid, team->t.t_id, tid, __kmp_gtid_from_tid(child_tid, team),
team->t.t_id, child_tid, &child_bar->b_arrived, new_state));
// Wait for child to arrive
kmp_flag_64 c_flag(&child_bar->b_arrived, new_state);
c_flag.wait(this_thr, FALSE USE_ITT_BUILD_ARG(itt_sync_obj));
ANNOTATE_BARRIER_END(child_thr);
#if USE_ITT_BUILD && USE_ITT_NOTIFY
// Barrier imbalance - write min of the thread time and a child time to
// the thread.
if (__kmp_forkjoin_frames_mode == 2) {
this_thr->th.th_bar_min_time = KMP_MIN(this_thr->th.th_bar_min_time,
child_thr->th.th_bar_min_time);
}
#endif
if (reduce) {
KA_TRACE(100,
("__kmp_hyper_barrier_gather: T#%d(%d:%d) += T#%d(%d:%u)\n",
gtid, team->t.t_id, tid, __kmp_gtid_from_tid(child_tid, team),
team->t.t_id, child_tid));
ANNOTATE_REDUCE_AFTER(reduce);
(*reduce)(this_thr->th.th_local.reduce_data,
child_thr->th.th_local.reduce_data);
ANNOTATE_REDUCE_BEFORE(reduce);
ANNOTATE_REDUCE_BEFORE(&team->t.t_bar);
}
}
}
if (KMP_MASTER_TID(tid)) {
// Need to update the team arrived pointer if we are the master thread
if (new_state == KMP_BARRIER_UNUSED_STATE)
team->t.t_bar[bt].b_arrived += KMP_BARRIER_STATE_BUMP;
else
team->t.t_bar[bt].b_arrived = new_state;
KA_TRACE(20, ("__kmp_hyper_barrier_gather: T#%d(%d:%d) set team %d "
"arrived(%p) = %llu\n",
gtid, team->t.t_id, tid, team->t.t_id,
&team->t.t_bar[bt].b_arrived, team->t.t_bar[bt].b_arrived));
}
KA_TRACE(
20, ("__kmp_hyper_barrier_gather: T#%d(%d:%d) exit for barrier type %d\n",
gtid, team->t.t_id, tid, bt));
}
// The reverse versions seem to beat the forward versions overall
#define KMP_REVERSE_HYPER_BAR
static void __kmp_hyper_barrier_release(
enum barrier_type bt, kmp_info_t *this_thr, int gtid, int tid,
int propagate_icvs USE_ITT_BUILD_ARG(void *itt_sync_obj)) {
KMP_TIME_DEVELOPER_PARTITIONED_BLOCK(KMP_hyper_release);
kmp_team_t *team;
kmp_bstate_t *thr_bar = &this_thr->th.th_bar[bt].bb;
kmp_info_t **other_threads;
kmp_uint32 num_threads;
kmp_uint32 branch_bits = __kmp_barrier_release_branch_bits[bt];
kmp_uint32 branch_factor = 1 << branch_bits;
kmp_uint32 child;
kmp_uint32 child_tid;
kmp_uint32 offset;
kmp_uint32 level;
/* Perform a hypercube-embedded tree release for all of the threads that have
been gathered. If KMP_REVERSE_HYPER_BAR is defined (default) the threads
are released in the reverse order of the corresponding gather, otherwise
threads are released in the same order. */
if (KMP_MASTER_TID(tid)) { // master
team = __kmp_threads[gtid]->th.th_team;
KMP_DEBUG_ASSERT(team != NULL);
KA_TRACE(20, ("__kmp_hyper_barrier_release: T#%d(%d:%d) master enter for "
"barrier type %d\n",
gtid, team->t.t_id, tid, bt));
#if KMP_BARRIER_ICV_PUSH
if (propagate_icvs) { // master already has ICVs in final destination; copy
copy_icvs(&thr_bar->th_fixed_icvs,
&team->t.t_implicit_task_taskdata[tid].td_icvs);
}
#endif
} else { // Handle fork barrier workers who aren't part of a team yet
KA_TRACE(20, ("__kmp_hyper_barrier_release: T#%d wait go(%p) == %u\n", gtid,
&thr_bar->b_go, KMP_BARRIER_STATE_BUMP));
// Wait for parent thread to release us
kmp_flag_64 flag(&thr_bar->b_go, KMP_BARRIER_STATE_BUMP);
flag.wait(this_thr, TRUE USE_ITT_BUILD_ARG(itt_sync_obj));
ANNOTATE_BARRIER_END(this_thr);
#if USE_ITT_BUILD && USE_ITT_NOTIFY
if ((__itt_sync_create_ptr && itt_sync_obj == NULL) || KMP_ITT_DEBUG) {
// In fork barrier where we could not get the object reliably
itt_sync_obj = __kmp_itt_barrier_object(gtid, bs_forkjoin_barrier, 0, -1);
// Cancel wait on previous parallel region...
__kmp_itt_task_starting(itt_sync_obj);
if (bt == bs_forkjoin_barrier && TCR_4(__kmp_global.g.g_done))
return;
itt_sync_obj = __kmp_itt_barrier_object(gtid, bs_forkjoin_barrier);
if (itt_sync_obj != NULL)
// Call prepare as early as possible for "new" barrier
__kmp_itt_task_finished(itt_sync_obj);
} else
#endif /* USE_ITT_BUILD && USE_ITT_NOTIFY */
// Early exit for reaping threads releasing forkjoin barrier
if (bt == bs_forkjoin_barrier && TCR_4(__kmp_global.g.g_done))
return;
// The worker thread may now assume that the team is valid.
team = __kmp_threads[gtid]->th.th_team;
KMP_DEBUG_ASSERT(team != NULL);
tid = __kmp_tid_from_gtid(gtid);
TCW_4(thr_bar->b_go, KMP_INIT_BARRIER_STATE);
KA_TRACE(20,
("__kmp_hyper_barrier_release: T#%d(%d:%d) set go(%p) = %u\n",
gtid, team->t.t_id, tid, &thr_bar->b_go, KMP_INIT_BARRIER_STATE));
KMP_MB(); // Flush all pending memory write invalidates.
}
num_threads = this_thr->th.th_team_nproc;
other_threads = team->t.t_threads;
#ifdef KMP_REVERSE_HYPER_BAR
// Count up to correct level for parent
for (level = 0, offset = 1;
offset < num_threads && (((tid >> level) & (branch_factor - 1)) == 0);
level += branch_bits, offset <<= branch_bits)
;
// Now go down from there
for (level -= branch_bits, offset >>= branch_bits; offset != 0;
level -= branch_bits, offset >>= branch_bits)
#else
// Go down the tree, level by level
for (level = 0, offset = 1; offset < num_threads;
level += branch_bits, offset <<= branch_bits)
#endif // KMP_REVERSE_HYPER_BAR
{
#ifdef KMP_REVERSE_HYPER_BAR
/* Now go in reverse order through the children, highest to lowest.
Initial setting of child is conservative here. */
child = num_threads >> ((level == 0) ? level : level - 1);
for (child = (child < branch_factor - 1) ? child : branch_factor - 1,
child_tid = tid + (child << level);
child >= 1; child--, child_tid -= (1 << level))
#else
if (((tid >> level) & (branch_factor - 1)) != 0)
// No need to go lower than this, since this is the level parent would be
// notified
break;
// Iterate through children on this level of the tree
for (child = 1, child_tid = tid + (1 << level);
child < branch_factor && child_tid < num_threads;
child++, child_tid += (1 << level))
#endif // KMP_REVERSE_HYPER_BAR
{
if (child_tid >= num_threads)
continue; // Child doesn't exist so keep going
else {
kmp_info_t *child_thr = other_threads[child_tid];
kmp_bstate_t *child_bar = &child_thr->th.th_bar[bt].bb;
#if KMP_CACHE_MANAGE
kmp_uint32 next_child_tid = child_tid - (1 << level);
// Prefetch next thread's go count
#ifdef KMP_REVERSE_HYPER_BAR
if (child - 1 >= 1 && next_child_tid < num_threads)
#else
if (child + 1 < branch_factor && next_child_tid < num_threads)
#endif // KMP_REVERSE_HYPER_BAR
KMP_CACHE_PREFETCH(
&other_threads[next_child_tid]->th.th_bar[bt].bb.b_go);
#endif /* KMP_CACHE_MANAGE */
#if KMP_BARRIER_ICV_PUSH
if (propagate_icvs) // push my fixed ICVs to my child
copy_icvs(&child_bar->th_fixed_icvs, &thr_bar->th_fixed_icvs);
#endif // KMP_BARRIER_ICV_PUSH
KA_TRACE(
20,
("__kmp_hyper_barrier_release: T#%d(%d:%d) releasing T#%d(%d:%u)"
"go(%p): %u => %u\n",
gtid, team->t.t_id, tid, __kmp_gtid_from_tid(child_tid, team),
team->t.t_id, child_tid, &child_bar->b_go, child_bar->b_go,
child_bar->b_go + KMP_BARRIER_STATE_BUMP));
// Release child from barrier
ANNOTATE_BARRIER_BEGIN(child_thr);
kmp_flag_64 flag(&child_bar->b_go, child_thr);
flag.release();
}
}
}
#if KMP_BARRIER_ICV_PUSH
if (propagate_icvs &&
!KMP_MASTER_TID(tid)) { // copy ICVs locally to final dest
__kmp_init_implicit_task(team->t.t_ident, team->t.t_threads[tid], team, tid,
FALSE);
copy_icvs(&team->t.t_implicit_task_taskdata[tid].td_icvs,
&thr_bar->th_fixed_icvs);
}
#endif
KA_TRACE(
20,
("__kmp_hyper_barrier_release: T#%d(%d:%d) exit for barrier type %d\n",
gtid, team->t.t_id, tid, bt));
}
// Hierarchical Barrier
// Initialize thread barrier data
/* Initializes/re-initializes the hierarchical barrier data stored on a thread.
Performs the minimum amount of initialization required based on how the team
has changed. Returns true if leaf children will require both on-core and
traditional wake-up mechanisms. For example, if the team size increases,
threads already in the team will respond to on-core wakeup on their parent
thread, but threads newly added to the team will only be listening on the
their local b_go. */
static bool __kmp_init_hierarchical_barrier_thread(enum barrier_type bt,
kmp_bstate_t *thr_bar,
kmp_uint32 nproc, int gtid,
int tid, kmp_team_t *team) {
// Checks to determine if (re-)initialization is needed
bool uninitialized = thr_bar->team == NULL;
bool team_changed = team != thr_bar->team;
bool team_sz_changed = nproc != thr_bar->nproc;
bool tid_changed = tid != thr_bar->old_tid;
bool retval = false;
if (uninitialized || team_sz_changed) {
__kmp_get_hierarchy(nproc, thr_bar);
}
if (uninitialized || team_sz_changed || tid_changed) {
thr_bar->my_level = thr_bar->depth - 1; // default for master
thr_bar->parent_tid = -1; // default for master
if (!KMP_MASTER_TID(
tid)) { // if not master, find parent thread in hierarchy
kmp_uint32 d = 0;
while (d < thr_bar->depth) { // find parent based on level of thread in
// hierarchy, and note level
kmp_uint32 rem;
if (d == thr_bar->depth - 2) { // reached level right below the master
thr_bar->parent_tid = 0;
thr_bar->my_level = d;
break;
} else if ((rem = tid % thr_bar->skip_per_level[d + 1]) !=
0) { // TODO: can we make this op faster?
// thread is not a subtree root at next level, so this is max
thr_bar->parent_tid = tid - rem;
thr_bar->my_level = d;
break;
}
++d;
}
}
thr_bar->offset = 7 - (tid - thr_bar->parent_tid - 1);
thr_bar->old_tid = tid;
thr_bar->wait_flag = KMP_BARRIER_NOT_WAITING;
thr_bar->team = team;
thr_bar->parent_bar =
&team->t.t_threads[thr_bar->parent_tid]->th.th_bar[bt].bb;
}
if (uninitialized || team_changed || tid_changed) {
thr_bar->team = team;
thr_bar->parent_bar =
&team->t.t_threads[thr_bar->parent_tid]->th.th_bar[bt].bb;
retval = true;
}
if (uninitialized || team_sz_changed || tid_changed) {
thr_bar->nproc = nproc;
thr_bar->leaf_kids = thr_bar->base_leaf_kids;
if (thr_bar->my_level == 0)
thr_bar->leaf_kids = 0;
if (thr_bar->leaf_kids && (kmp_uint32)tid + thr_bar->leaf_kids + 1 > nproc)
thr_bar->leaf_kids = nproc - tid - 1;
thr_bar->leaf_state = 0;
for (int i = 0; i < thr_bar->leaf_kids; ++i)
((char *)&(thr_bar->leaf_state))[7 - i] = 1;
}
return retval;
}
static void __kmp_hierarchical_barrier_gather(
enum barrier_type bt, kmp_info_t *this_thr, int gtid, int tid,
void (*reduce)(void *, void *) USE_ITT_BUILD_ARG(void *itt_sync_obj)) {
KMP_TIME_DEVELOPER_PARTITIONED_BLOCK(KMP_hier_gather);
kmp_team_t *team = this_thr->th.th_team;
kmp_bstate_t *thr_bar = &this_thr->th.th_bar[bt].bb;
kmp_uint32 nproc = this_thr->th.th_team_nproc;
kmp_info_t **other_threads = team->t.t_threads;
kmp_uint64 new_state;
int level = team->t.t_level;
#if OMP_40_ENABLED
if (other_threads[0]
->th.th_teams_microtask) // are we inside the teams construct?
if (this_thr->th.th_teams_size.nteams > 1)
++level; // level was not increased in teams construct for team_of_masters
#endif
if (level == 1)
thr_bar->use_oncore_barrier = 1;
else
thr_bar->use_oncore_barrier = 0; // Do not use oncore barrier when nested
KA_TRACE(20, ("__kmp_hierarchical_barrier_gather: T#%d(%d:%d) enter for "
"barrier type %d\n",
gtid, team->t.t_id, tid, bt));
KMP_DEBUG_ASSERT(this_thr == other_threads[this_thr->th.th_info.ds.ds_tid]);
#if USE_ITT_BUILD && USE_ITT_NOTIFY
// Barrier imbalance - save arrive time to the thread
if (__kmp_forkjoin_frames_mode == 3 || __kmp_forkjoin_frames_mode == 2) {
this_thr->th.th_bar_arrive_time = __itt_get_timestamp();
}
#endif
(void)__kmp_init_hierarchical_barrier_thread(bt, thr_bar, nproc, gtid, tid,
team);
if (thr_bar->my_level) { // not a leaf (my_level==0 means leaf)
kmp_int32 child_tid;
new_state =
(kmp_uint64)team->t.t_bar[bt].b_arrived + KMP_BARRIER_STATE_BUMP;
if (__kmp_dflt_blocktime == KMP_MAX_BLOCKTIME &&
thr_bar->use_oncore_barrier) {
if (thr_bar->leaf_kids) {
// First, wait for leaf children to check-in on my b_arrived flag
kmp_uint64 leaf_state =
KMP_MASTER_TID(tid)
? thr_bar->b_arrived | thr_bar->leaf_state
: team->t.t_bar[bt].b_arrived | thr_bar->leaf_state;
KA_TRACE(20, ("__kmp_hierarchical_barrier_gather: T#%d(%d:%d) waiting "
"for leaf kids\n",
gtid, team->t.t_id, tid));
kmp_flag_64 flag(&thr_bar->b_arrived, leaf_state);
flag.wait(this_thr, FALSE USE_ITT_BUILD_ARG(itt_sync_obj));
if (reduce) {
ANNOTATE_REDUCE_AFTER(reduce);
for (child_tid = tid + 1; child_tid <= tid + thr_bar->leaf_kids;
++child_tid) {
KA_TRACE(100, ("__kmp_hierarchical_barrier_gather: T#%d(%d:%d) += "
"T#%d(%d:%d)\n",
gtid, team->t.t_id, tid,
__kmp_gtid_from_tid(child_tid, team), team->t.t_id,
child_tid));
ANNOTATE_BARRIER_END(other_threads[child_tid]);
(*reduce)(this_thr->th.th_local.reduce_data,
other_threads[child_tid]->th.th_local.reduce_data);
}
ANNOTATE_REDUCE_BEFORE(reduce);
ANNOTATE_REDUCE_BEFORE(&team->t.t_bar);
}
// clear leaf_state bits
KMP_TEST_THEN_AND64(&thr_bar->b_arrived, ~(thr_bar->leaf_state));
}
// Next, wait for higher level children on each child's b_arrived flag
for (kmp_uint32 d = 1; d < thr_bar->my_level;
++d) { // gather lowest level threads first, but skip 0
kmp_uint32 last = tid + thr_bar->skip_per_level[d + 1],
skip = thr_bar->skip_per_level[d];
if (last > nproc)
last = nproc;
for (child_tid = tid + skip; child_tid < (int)last; child_tid += skip) {
kmp_info_t *child_thr = other_threads[child_tid];
kmp_bstate_t *child_bar = &child_thr->th.th_bar[bt].bb;
KA_TRACE(20, ("__kmp_hierarchical_barrier_gather: T#%d(%d:%d) wait "
"T#%d(%d:%d) "
"arrived(%p) == %llu\n",
gtid, team->t.t_id, tid,
__kmp_gtid_from_tid(child_tid, team), team->t.t_id,
child_tid, &child_bar->b_arrived, new_state));
kmp_flag_64 flag(&child_bar->b_arrived, new_state);
flag.wait(this_thr, FALSE USE_ITT_BUILD_ARG(itt_sync_obj));
ANNOTATE_BARRIER_END(child_thr);
if (reduce) {
KA_TRACE(100, ("__kmp_hierarchical_barrier_gather: T#%d(%d:%d) += "
"T#%d(%d:%d)\n",
gtid, team->t.t_id, tid,
__kmp_gtid_from_tid(child_tid, team), team->t.t_id,
child_tid));
ANNOTATE_REDUCE_AFTER(reduce);
(*reduce)(this_thr->th.th_local.reduce_data,
child_thr->th.th_local.reduce_data);
ANNOTATE_REDUCE_BEFORE(reduce);
ANNOTATE_REDUCE_BEFORE(&team->t.t_bar);
}
}
}
} else { // Blocktime is not infinite
for (kmp_uint32 d = 0; d < thr_bar->my_level;
++d) { // Gather lowest level threads first
kmp_uint32 last = tid + thr_bar->skip_per_level[d + 1],
skip = thr_bar->skip_per_level[d];
if (last > nproc)
last = nproc;
for (child_tid = tid + skip; child_tid < (int)last; child_tid += skip) {
kmp_info_t *child_thr = other_threads[child_tid];
kmp_bstate_t *child_bar = &child_thr->th.th_bar[bt].bb;
KA_TRACE(20, ("__kmp_hierarchical_barrier_gather: T#%d(%d:%d) wait "
"T#%d(%d:%d) "
"arrived(%p) == %llu\n",
gtid, team->t.t_id, tid,
__kmp_gtid_from_tid(child_tid, team), team->t.t_id,
child_tid, &child_bar->b_arrived, new_state));
kmp_flag_64 flag(&child_bar->b_arrived, new_state);
flag.wait(this_thr, FALSE USE_ITT_BUILD_ARG(itt_sync_obj));
ANNOTATE_BARRIER_END(child_thr);
if (reduce) {
KA_TRACE(100, ("__kmp_hierarchical_barrier_gather: T#%d(%d:%d) += "
"T#%d(%d:%d)\n",
gtid, team->t.t_id, tid,
__kmp_gtid_from_tid(child_tid, team), team->t.t_id,
child_tid));
ANNOTATE_REDUCE_AFTER(reduce);
(*reduce)(this_thr->th.th_local.reduce_data,
child_thr->th.th_local.reduce_data);
ANNOTATE_REDUCE_BEFORE(reduce);
ANNOTATE_REDUCE_BEFORE(&team->t.t_bar);
}
}
}
}
}
// All subordinates are gathered; now release parent if not master thread
if (!KMP_MASTER_TID(tid)) { // worker threads release parent in hierarchy
KA_TRACE(20, ("__kmp_hierarchical_barrier_gather: T#%d(%d:%d) releasing"
" T#%d(%d:%d) arrived(%p): %llu => %llu\n",
gtid, team->t.t_id, tid,
__kmp_gtid_from_tid(thr_bar->parent_tid, team), team->t.t_id,
thr_bar->parent_tid, &thr_bar->b_arrived, thr_bar->b_arrived,
thr_bar->b_arrived + KMP_BARRIER_STATE_BUMP));
/* Mark arrival to parent: After performing this write, a worker thread may
not assume that the team is valid any more - it could be deallocated by
the master thread at any time. */
if (thr_bar->my_level || __kmp_dflt_blocktime != KMP_MAX_BLOCKTIME ||
!thr_bar->use_oncore_barrier) { // Parent is waiting on my b_arrived
// flag; release it
ANNOTATE_BARRIER_BEGIN(this_thr);
kmp_flag_64 flag(&thr_bar->b_arrived, other_threads[thr_bar->parent_tid]);
flag.release();
} else {
// Leaf does special release on "offset" bits of parent's b_arrived flag
thr_bar->b_arrived = team->t.t_bar[bt].b_arrived + KMP_BARRIER_STATE_BUMP;
kmp_flag_oncore flag(&thr_bar->parent_bar->b_arrived, thr_bar->offset);
flag.set_waiter(other_threads[thr_bar->parent_tid]);
flag.release();
}
} else { // Master thread needs to update the team's b_arrived value
team->t.t_bar[bt].b_arrived = new_state;
KA_TRACE(20, ("__kmp_hierarchical_barrier_gather: T#%d(%d:%d) set team %d "
"arrived(%p) = %llu\n",
gtid, team->t.t_id, tid, team->t.t_id,
&team->t.t_bar[bt].b_arrived, team->t.t_bar[bt].b_arrived));
}
// Is the team access below unsafe or just technically invalid?
KA_TRACE(20, ("__kmp_hierarchical_barrier_gather: T#%d(%d:%d) exit for "
"barrier type %d\n",
gtid, team->t.t_id, tid, bt));
}
static void __kmp_hierarchical_barrier_release(
enum barrier_type bt, kmp_info_t *this_thr, int gtid, int tid,
int propagate_icvs USE_ITT_BUILD_ARG(void *itt_sync_obj)) {
KMP_TIME_DEVELOPER_PARTITIONED_BLOCK(KMP_hier_release);
kmp_team_t *team;
kmp_bstate_t *thr_bar = &this_thr->th.th_bar[bt].bb;
kmp_uint32 nproc;
bool team_change = false; // indicates on-core barrier shouldn't be used
if (KMP_MASTER_TID(tid)) {
team = __kmp_threads[gtid]->th.th_team;
KMP_DEBUG_ASSERT(team != NULL);
KA_TRACE(20, ("__kmp_hierarchical_barrier_release: T#%d(%d:%d) master "
"entered barrier type %d\n",
gtid, team->t.t_id, tid, bt));
} else { // Worker threads
// Wait for parent thread to release me
if (!thr_bar->use_oncore_barrier ||
__kmp_dflt_blocktime != KMP_MAX_BLOCKTIME || thr_bar->my_level != 0 ||
thr_bar->team == NULL) {
// Use traditional method of waiting on my own b_go flag
thr_bar->wait_flag = KMP_BARRIER_OWN_FLAG;
kmp_flag_64 flag(&thr_bar->b_go, KMP_BARRIER_STATE_BUMP);
flag.wait(this_thr, TRUE USE_ITT_BUILD_ARG(itt_sync_obj));
ANNOTATE_BARRIER_END(this_thr);
TCW_8(thr_bar->b_go,
KMP_INIT_BARRIER_STATE); // Reset my b_go flag for next time
} else { // Thread barrier data is initialized, this is a leaf, blocktime is
// infinite, not nested
// Wait on my "offset" bits on parent's b_go flag
thr_bar->wait_flag = KMP_BARRIER_PARENT_FLAG;
kmp_flag_oncore flag(&thr_bar->parent_bar->b_go, KMP_BARRIER_STATE_BUMP,
thr_bar->offset, bt,
this_thr USE_ITT_BUILD_ARG(itt_sync_obj));
flag.wait(this_thr, TRUE);
if (thr_bar->wait_flag ==
KMP_BARRIER_SWITCHING) { // Thread was switched to own b_go
TCW_8(thr_bar->b_go,
KMP_INIT_BARRIER_STATE); // Reset my b_go flag for next time
} else { // Reset my bits on parent's b_go flag
(RCAST(volatile char *,
&(thr_bar->parent_bar->b_go)))[thr_bar->offset] = 0;
}
}
thr_bar->wait_flag = KMP_BARRIER_NOT_WAITING;
// Early exit for reaping threads releasing forkjoin barrier
if (bt == bs_forkjoin_barrier && TCR_4(__kmp_global.g.g_done))
return;
// The worker thread may now assume that the team is valid.
team = __kmp_threads[gtid]->th.th_team;
KMP_DEBUG_ASSERT(team != NULL);
tid = __kmp_tid_from_gtid(gtid);
KA_TRACE(
20,
("__kmp_hierarchical_barrier_release: T#%d(%d:%d) set go(%p) = %u\n",
gtid, team->t.t_id, tid, &thr_bar->b_go, KMP_INIT_BARRIER_STATE));
KMP_MB(); // Flush all pending memory write invalidates.
}
nproc = this_thr->th.th_team_nproc;
int level = team->t.t_level;
#if OMP_40_ENABLED
if (team->t.t_threads[0]
->th.th_teams_microtask) { // are we inside the teams construct?
if (team->t.t_pkfn != (microtask_t)__kmp_teams_master &&
this_thr->th.th_teams_level == level)
++level; // level was not increased in teams construct for team_of_workers
if (this_thr->th.th_teams_size.nteams > 1)
++level; // level was not increased in teams construct for team_of_masters
}
#endif
if (level == 1)
thr_bar->use_oncore_barrier = 1;
else
thr_bar->use_oncore_barrier = 0; // Do not use oncore barrier when nested
// If the team size has increased, we still communicate with old leaves via
// oncore barrier.
unsigned short int old_leaf_kids = thr_bar->leaf_kids;
kmp_uint64 old_leaf_state = thr_bar->leaf_state;
team_change = __kmp_init_hierarchical_barrier_thread(bt, thr_bar, nproc, gtid,
tid, team);
// But if the entire team changes, we won't use oncore barrier at all
if (team_change)
old_leaf_kids = 0;
#if KMP_BARRIER_ICV_PUSH
if (propagate_icvs) {
__kmp_init_implicit_task(team->t.t_ident, team->t.t_threads[tid], team, tid,
FALSE);
if (KMP_MASTER_TID(
tid)) { // master already has copy in final destination; copy
copy_icvs(&thr_bar->th_fixed_icvs,
&team->t.t_implicit_task_taskdata[tid].td_icvs);
} else if (__kmp_dflt_blocktime == KMP_MAX_BLOCKTIME &&
thr_bar->use_oncore_barrier) { // optimization for inf blocktime
if (!thr_bar->my_level) // I'm a leaf in the hierarchy (my_level==0)
// leaves (on-core children) pull parent's fixed ICVs directly to local
// ICV store
copy_icvs(&team->t.t_implicit_task_taskdata[tid].td_icvs,
&thr_bar->parent_bar->th_fixed_icvs);
// non-leaves will get ICVs piggybacked with b_go via NGO store
} else { // blocktime is not infinite; pull ICVs from parent's fixed ICVs
if (thr_bar->my_level) // not a leaf; copy ICVs to my fixed ICVs child can
// access
copy_icvs(&thr_bar->th_fixed_icvs, &thr_bar->parent_bar->th_fixed_icvs);
else // leaves copy parent's fixed ICVs directly to local ICV store
copy_icvs(&team->t.t_implicit_task_taskdata[tid].td_icvs,
&thr_bar->parent_bar->th_fixed_icvs);
}
}
#endif // KMP_BARRIER_ICV_PUSH
// Now, release my children
if (thr_bar->my_level) { // not a leaf
kmp_int32 child_tid;
kmp_uint32 last;
if (__kmp_dflt_blocktime == KMP_MAX_BLOCKTIME &&
thr_bar->use_oncore_barrier) {
if (KMP_MASTER_TID(tid)) { // do a flat release
// Set local b_go to bump children via NGO store of the cache line
// containing IVCs and b_go.
thr_bar->b_go = KMP_BARRIER_STATE_BUMP;
// Use ngo stores if available; b_go piggybacks in the last 8 bytes of
// the cache line
ngo_load(&thr_bar->th_fixed_icvs);
// This loops over all the threads skipping only the leaf nodes in the
// hierarchy
for (child_tid = thr_bar->skip_per_level[1]; child_tid < (int)nproc;
child_tid += thr_bar->skip_per_level[1]) {
kmp_bstate_t *child_bar =
&team->t.t_threads[child_tid]->th.th_bar[bt].bb;
KA_TRACE(20, ("__kmp_hierarchical_barrier_release: T#%d(%d:%d) "
"releasing T#%d(%d:%d)"
" go(%p): %u => %u\n",
gtid, team->t.t_id, tid,
__kmp_gtid_from_tid(child_tid, team), team->t.t_id,
child_tid, &child_bar->b_go, child_bar->b_go,
child_bar->b_go + KMP_BARRIER_STATE_BUMP));
// Use ngo store (if available) to both store ICVs and release child
// via child's b_go
ngo_store_go(&child_bar->th_fixed_icvs, &thr_bar->th_fixed_icvs);
}
ngo_sync();
}
TCW_8(thr_bar->b_go,
KMP_INIT_BARRIER_STATE); // Reset my b_go flag for next time
// Now, release leaf children
if (thr_bar->leaf_kids) { // if there are any
// We test team_change on the off-chance that the level 1 team changed.
if (team_change ||
old_leaf_kids < thr_bar->leaf_kids) { // some old, some new
if (old_leaf_kids) { // release old leaf kids
thr_bar->b_go |= old_leaf_state;
}
// Release new leaf kids
last = tid + thr_bar->skip_per_level[1];
if (last > nproc)
last = nproc;
for (child_tid = tid + 1 + old_leaf_kids; child_tid < (int)last;
++child_tid) { // skip_per_level[0]=1
kmp_info_t *child_thr = team->t.t_threads[child_tid];
kmp_bstate_t *child_bar = &child_thr->th.th_bar[bt].bb;
KA_TRACE(
20,
("__kmp_hierarchical_barrier_release: T#%d(%d:%d) releasing"
" T#%d(%d:%d) go(%p): %u => %u\n",
gtid, team->t.t_id, tid, __kmp_gtid_from_tid(child_tid, team),
team->t.t_id, child_tid, &child_bar->b_go, child_bar->b_go,
child_bar->b_go + KMP_BARRIER_STATE_BUMP));
// Release child using child's b_go flag
ANNOTATE_BARRIER_BEGIN(child_thr);
kmp_flag_64 flag(&child_bar->b_go, child_thr);
flag.release();
}
} else { // Release all children at once with leaf_state bits on my own
// b_go flag
thr_bar->b_go |= thr_bar->leaf_state;
}
}
} else { // Blocktime is not infinite; do a simple hierarchical release
for (int d = thr_bar->my_level - 1; d >= 0;
--d) { // Release highest level threads first
last = tid + thr_bar->skip_per_level[d + 1];
kmp_uint32 skip = thr_bar->skip_per_level[d];
if (last > nproc)
last = nproc;
for (child_tid = tid + skip; child_tid < (int)last; child_tid += skip) {
kmp_info_t *child_thr = team->t.t_threads[child_tid];
kmp_bstate_t *child_bar = &child_thr->th.th_bar[bt].bb;
KA_TRACE(20, ("__kmp_hierarchical_barrier_release: T#%d(%d:%d) "
"releasing T#%d(%d:%d) go(%p): %u => %u\n",
gtid, team->t.t_id, tid,
__kmp_gtid_from_tid(child_tid, team), team->t.t_id,
child_tid, &child_bar->b_go, child_bar->b_go,
child_bar->b_go + KMP_BARRIER_STATE_BUMP));
// Release child using child's b_go flag
ANNOTATE_BARRIER_BEGIN(child_thr);
kmp_flag_64 flag(&child_bar->b_go, child_thr);
flag.release();
}
}
}
#if KMP_BARRIER_ICV_PUSH
if (propagate_icvs && !KMP_MASTER_TID(tid))
// non-leaves copy ICVs from fixed ICVs to local dest
copy_icvs(&team->t.t_implicit_task_taskdata[tid].td_icvs,
&thr_bar->th_fixed_icvs);
#endif // KMP_BARRIER_ICV_PUSH
}
KA_TRACE(20, ("__kmp_hierarchical_barrier_release: T#%d(%d:%d) exit for "
"barrier type %d\n",
gtid, team->t.t_id, tid, bt));
}
// End of Barrier Algorithms
// Internal function to do a barrier.
/* If is_split is true, do a split barrier, otherwise, do a plain barrier
If reduce is non-NULL, do a split reduction barrier, otherwise, do a split
barrier
Returns 0 if master thread, 1 if worker thread. */
int __kmp_barrier(enum barrier_type bt, int gtid, int is_split,
size_t reduce_size, void *reduce_data,
void (*reduce)(void *, void *)) {
KMP_TIME_PARTITIONED_BLOCK(OMP_plain_barrier);
KMP_SET_THREAD_STATE_BLOCK(PLAIN_BARRIER);
int tid = __kmp_tid_from_gtid(gtid);
kmp_info_t *this_thr = __kmp_threads[gtid];
kmp_team_t *team = this_thr->th.th_team;
int status = 0;
ident_t *loc = __kmp_threads[gtid]->th.th_ident;
#if OMPT_SUPPORT
ompt_data_t *my_task_data;
ompt_data_t *my_parallel_data;
void *return_address;
#endif
KA_TRACE(15, ("__kmp_barrier: T#%d(%d:%d) has arrived\n", gtid,
__kmp_team_from_gtid(gtid)->t.t_id, __kmp_tid_from_gtid(gtid)));
ANNOTATE_BARRIER_BEGIN(&team->t.t_bar);
#if OMPT_SUPPORT
if (ompt_enabled.enabled) {
#if OMPT_OPTIONAL
my_task_data = OMPT_CUR_TASK_DATA(this_thr);
my_parallel_data = OMPT_CUR_TEAM_DATA(this_thr);
return_address = OMPT_LOAD_RETURN_ADDRESS(gtid);
if (ompt_enabled.ompt_callback_sync_region) {
ompt_callbacks.ompt_callback(ompt_callback_sync_region)(
ompt_sync_region_barrier, ompt_scope_begin, my_parallel_data,
my_task_data, return_address);
}
if (ompt_enabled.ompt_callback_sync_region_wait) {
ompt_callbacks.ompt_callback(ompt_callback_sync_region_wait)(
ompt_sync_region_barrier, ompt_scope_begin, my_parallel_data,
my_task_data, return_address);
}
#endif
// It is OK to report the barrier state after the barrier begin callback.
// According to the OMPT specification, a compliant implementation may
// even delay reporting this state until the barrier begins to wait.
this_thr->th.ompt_thread_info.state = omp_state_wait_barrier;
}
#endif
if (!team->t.t_serialized) {
#if USE_ITT_BUILD
// This value will be used in itt notify events below.
void *itt_sync_obj = NULL;
#if USE_ITT_NOTIFY
if (__itt_sync_create_ptr || KMP_ITT_DEBUG)
itt_sync_obj = __kmp_itt_barrier_object(gtid, bt, 1);
#endif
#endif /* USE_ITT_BUILD */
if (__kmp_tasking_mode == tskm_extra_barrier) {
__kmp_tasking_barrier(team, this_thr, gtid);
KA_TRACE(15,
("__kmp_barrier: T#%d(%d:%d) past tasking barrier\n", gtid,
__kmp_team_from_gtid(gtid)->t.t_id, __kmp_tid_from_gtid(gtid)));
}
/* Copy the blocktime info to the thread, where __kmp_wait_template() can
access it when the team struct is not guaranteed to exist. */
// See note about the corresponding code in __kmp_join_barrier() being
// performance-critical.
if (__kmp_dflt_blocktime != KMP_MAX_BLOCKTIME) {
#if KMP_USE_MONITOR
this_thr->th.th_team_bt_intervals =
team->t.t_implicit_task_taskdata[tid].td_icvs.bt_intervals;
this_thr->th.th_team_bt_set =
team->t.t_implicit_task_taskdata[tid].td_icvs.bt_set;
#else
this_thr->th.th_team_bt_intervals = KMP_BLOCKTIME_INTERVAL(team, tid);
#endif
}
#if USE_ITT_BUILD
if (__itt_sync_create_ptr || KMP_ITT_DEBUG)
__kmp_itt_barrier_starting(gtid, itt_sync_obj);
#endif /* USE_ITT_BUILD */
#if USE_DEBUGGER
// Let the debugger know: the thread arrived to the barrier and waiting.
if (KMP_MASTER_TID(tid)) { // Master counter is stored in team structure.
team->t.t_bar[bt].b_master_arrived += 1;
} else {
this_thr->th.th_bar[bt].bb.b_worker_arrived += 1;
} // if
#endif /* USE_DEBUGGER */
if (reduce != NULL) {
// KMP_DEBUG_ASSERT( is_split == TRUE ); // #C69956
this_thr->th.th_local.reduce_data = reduce_data;
}
if (KMP_MASTER_TID(tid) && __kmp_tasking_mode != tskm_immediate_exec)
__kmp_task_team_setup(
this_thr, team,
0); // use 0 to only setup the current team if nthreads > 1
switch (__kmp_barrier_gather_pattern[bt]) {
case bp_hyper_bar: {
KMP_ASSERT(__kmp_barrier_gather_branch_bits[bt]); // don't set branch bits
// to 0; use linear
__kmp_hyper_barrier_gather(bt, this_thr, gtid, tid,
reduce USE_ITT_BUILD_ARG(itt_sync_obj));
break;
}
case bp_hierarchical_bar: {
__kmp_hierarchical_barrier_gather(bt, this_thr, gtid, tid,
reduce USE_ITT_BUILD_ARG(itt_sync_obj));
break;
}
case bp_tree_bar: {
KMP_ASSERT(__kmp_barrier_gather_branch_bits[bt]); // don't set branch bits
// to 0; use linear
__kmp_tree_barrier_gather(bt, this_thr, gtid, tid,
reduce USE_ITT_BUILD_ARG(itt_sync_obj));
break;
}
default: {
__kmp_linear_barrier_gather(bt, this_thr, gtid, tid,
reduce USE_ITT_BUILD_ARG(itt_sync_obj));
}
}
KMP_MB();
if (KMP_MASTER_TID(tid)) {
status = 0;
if (__kmp_tasking_mode != tskm_immediate_exec) {
__kmp_task_team_wait(this_thr, team USE_ITT_BUILD_ARG(itt_sync_obj));
}
#if USE_DEBUGGER
// Let the debugger know: All threads are arrived and starting leaving the
// barrier.
team->t.t_bar[bt].b_team_arrived += 1;
#endif
#if OMP_40_ENABLED
kmp_int32 cancel_request = KMP_ATOMIC_LD_RLX(&team->t.t_cancel_request);
// Reset cancellation flag for worksharing constructs
if (cancel_request == cancel_loop || cancel_request == cancel_sections) {
KMP_ATOMIC_ST_RLX(&team->t.t_cancel_request, cancel_noreq);
}
#endif
#if USE_ITT_BUILD
/* TODO: In case of split reduction barrier, master thread may send
acquired event early, before the final summation into the shared
variable is done (final summation can be a long operation for array
reductions). */
if (__itt_sync_create_ptr || KMP_ITT_DEBUG)
__kmp_itt_barrier_middle(gtid, itt_sync_obj);
#endif /* USE_ITT_BUILD */
#if USE_ITT_BUILD && USE_ITT_NOTIFY
// Barrier - report frame end (only if active_level == 1)
if ((__itt_frame_submit_v3_ptr || KMP_ITT_DEBUG) &&
__kmp_forkjoin_frames_mode &&
#if OMP_40_ENABLED
this_thr->th.th_teams_microtask == NULL &&
#endif
team->t.t_active_level == 1) {
kmp_uint64 cur_time = __itt_get_timestamp();
kmp_info_t **other_threads = team->t.t_threads;
int nproc = this_thr->th.th_team_nproc;
int i;
switch (__kmp_forkjoin_frames_mode) {
case 1:
__kmp_itt_frame_submit(gtid, this_thr->th.th_frame_time, cur_time, 0,
loc, nproc);
this_thr->th.th_frame_time = cur_time;
break;
case 2: // AC 2015-01-19: currently does not work for hierarchical (to
// be fixed)
__kmp_itt_frame_submit(gtid, this_thr->th.th_bar_min_time, cur_time,
1, loc, nproc);
break;
case 3:
if (__itt_metadata_add_ptr) {
// Initialize with master's wait time
kmp_uint64 delta = cur_time - this_thr->th.th_bar_arrive_time;
// Set arrive time to zero to be able to check it in
// __kmp_invoke_task(); the same is done inside the loop below
this_thr->th.th_bar_arrive_time = 0;
for (i = 1; i < nproc; ++i) {
delta += (cur_time - other_threads[i]->th.th_bar_arrive_time);
other_threads[i]->th.th_bar_arrive_time = 0;
}
__kmp_itt_metadata_imbalance(gtid, this_thr->th.th_frame_time,
cur_time, delta,
(kmp_uint64)(reduce != NULL));
}
__kmp_itt_frame_submit(gtid, this_thr->th.th_frame_time, cur_time, 0,
loc, nproc);
this_thr->th.th_frame_time = cur_time;
break;
}
}
#endif /* USE_ITT_BUILD */
} else {
status = 1;
#if USE_ITT_BUILD
if (__itt_sync_create_ptr || KMP_ITT_DEBUG)
__kmp_itt_barrier_middle(gtid, itt_sync_obj);
#endif /* USE_ITT_BUILD */
}
if (status == 1 || !is_split) {
switch (__kmp_barrier_release_pattern[bt]) {
case bp_hyper_bar: {
KMP_ASSERT(__kmp_barrier_release_branch_bits[bt]);
__kmp_hyper_barrier_release(bt, this_thr, gtid, tid,
FALSE USE_ITT_BUILD_ARG(itt_sync_obj));
break;
}
case bp_hierarchical_bar: {
__kmp_hierarchical_barrier_release(
bt, this_thr, gtid, tid, FALSE USE_ITT_BUILD_ARG(itt_sync_obj));
break;
}
case bp_tree_bar: {
KMP_ASSERT(__kmp_barrier_release_branch_bits[bt]);
__kmp_tree_barrier_release(bt, this_thr, gtid, tid,
FALSE USE_ITT_BUILD_ARG(itt_sync_obj));
break;
}
default: {
__kmp_linear_barrier_release(bt, this_thr, gtid, tid,
FALSE USE_ITT_BUILD_ARG(itt_sync_obj));
}
}
if (__kmp_tasking_mode != tskm_immediate_exec) {
__kmp_task_team_sync(this_thr, team);
}
}
#if USE_ITT_BUILD
/* GEH: TODO: Move this under if-condition above and also include in
__kmp_end_split_barrier(). This will more accurately represent the actual
release time of the threads for split barriers. */
if (__itt_sync_create_ptr || KMP_ITT_DEBUG)
__kmp_itt_barrier_finished(gtid, itt_sync_obj);
#endif /* USE_ITT_BUILD */
} else { // Team is serialized.
status = 0;
if (__kmp_tasking_mode != tskm_immediate_exec) {
#if OMP_45_ENABLED
if (this_thr->th.th_task_team != NULL) {
void *itt_sync_obj = NULL;
#if USE_ITT_NOTIFY
if (__itt_sync_create_ptr || KMP_ITT_DEBUG) {
itt_sync_obj = __kmp_itt_barrier_object(gtid, bt, 1);
__kmp_itt_barrier_starting(gtid, itt_sync_obj);
}
#endif
KMP_DEBUG_ASSERT(this_thr->th.th_task_team->tt.tt_found_proxy_tasks ==
TRUE);
__kmp_task_team_wait(this_thr, team USE_ITT_BUILD_ARG(itt_sync_obj));
__kmp_task_team_setup(this_thr, team, 0);
#if USE_ITT_BUILD
if (__itt_sync_create_ptr || KMP_ITT_DEBUG)
__kmp_itt_barrier_finished(gtid, itt_sync_obj);
#endif /* USE_ITT_BUILD */
}
#else
// The task team should be NULL for serialized code (tasks will be
// executed immediately)
KMP_DEBUG_ASSERT(team->t.t_task_team[this_thr->th.th_task_state] == NULL);
KMP_DEBUG_ASSERT(this_thr->th.th_task_team == NULL);
#endif
}
}
KA_TRACE(15, ("__kmp_barrier: T#%d(%d:%d) is leaving with return value %d\n",
gtid, __kmp_team_from_gtid(gtid)->t.t_id,
__kmp_tid_from_gtid(gtid), status));
#if OMPT_SUPPORT
if (ompt_enabled.enabled) {
#if OMPT_OPTIONAL
if (ompt_enabled.ompt_callback_sync_region_wait) {
ompt_callbacks.ompt_callback(ompt_callback_sync_region_wait)(
ompt_sync_region_barrier, ompt_scope_end, my_parallel_data,
my_task_data, return_address);
}
if (ompt_enabled.ompt_callback_sync_region) {
ompt_callbacks.ompt_callback(ompt_callback_sync_region)(
ompt_sync_region_barrier, ompt_scope_end, my_parallel_data,
my_task_data, return_address);
}
#endif
this_thr->th.ompt_thread_info.state = omp_state_work_parallel;
}
#endif
ANNOTATE_BARRIER_END(&team->t.t_bar);
return status;
}
void __kmp_end_split_barrier(enum barrier_type bt, int gtid) {
KMP_TIME_DEVELOPER_PARTITIONED_BLOCK(KMP_end_split_barrier);
KMP_SET_THREAD_STATE_BLOCK(PLAIN_BARRIER);
int tid = __kmp_tid_from_gtid(gtid);
kmp_info_t *this_thr = __kmp_threads[gtid];
kmp_team_t *team = this_thr->th.th_team;
ANNOTATE_BARRIER_BEGIN(&team->t.t_bar);
if (!team->t.t_serialized) {
if (KMP_MASTER_GTID(gtid)) {
switch (__kmp_barrier_release_pattern[bt]) {
case bp_hyper_bar: {
KMP_ASSERT(__kmp_barrier_release_branch_bits[bt]);
__kmp_hyper_barrier_release(bt, this_thr, gtid, tid,
FALSE USE_ITT_BUILD_ARG(NULL));
break;
}
case bp_hierarchical_bar: {
__kmp_hierarchical_barrier_release(bt, this_thr, gtid, tid,
FALSE USE_ITT_BUILD_ARG(NULL));
break;
}
case bp_tree_bar: {
KMP_ASSERT(__kmp_barrier_release_branch_bits[bt]);
__kmp_tree_barrier_release(bt, this_thr, gtid, tid,
FALSE USE_ITT_BUILD_ARG(NULL));
break;
}
default: {
__kmp_linear_barrier_release(bt, this_thr, gtid, tid,
FALSE USE_ITT_BUILD_ARG(NULL));
}
}
if (__kmp_tasking_mode != tskm_immediate_exec) {
__kmp_task_team_sync(this_thr, team);
} // if
}
}
ANNOTATE_BARRIER_END(&team->t.t_bar);
}
void __kmp_join_barrier(int gtid) {
KMP_TIME_PARTITIONED_BLOCK(OMP_join_barrier);
KMP_SET_THREAD_STATE_BLOCK(FORK_JOIN_BARRIER);
kmp_info_t *this_thr = __kmp_threads[gtid];
kmp_team_t *team;
kmp_uint nproc;
kmp_info_t *master_thread;
int tid;
#ifdef KMP_DEBUG
int team_id;
#endif /* KMP_DEBUG */
#if USE_ITT_BUILD
void *itt_sync_obj = NULL;
#if USE_ITT_NOTIFY
if (__itt_sync_create_ptr || KMP_ITT_DEBUG) // Don't call routine without need
// Get object created at fork_barrier
itt_sync_obj = __kmp_itt_barrier_object(gtid, bs_forkjoin_barrier);
#endif
#endif /* USE_ITT_BUILD */
KMP_MB();
// Get current info
team = this_thr->th.th_team;
nproc = this_thr->th.th_team_nproc;
KMP_DEBUG_ASSERT((int)nproc == team->t.t_nproc);
tid = __kmp_tid_from_gtid(gtid);
#ifdef KMP_DEBUG
team_id = team->t.t_id;
#endif /* KMP_DEBUG */
master_thread = this_thr->th.th_team_master;
#ifdef KMP_DEBUG
if (master_thread != team->t.t_threads[0]) {
__kmp_print_structure();
}
#endif /* KMP_DEBUG */
KMP_DEBUG_ASSERT(master_thread == team->t.t_threads[0]);
KMP_MB();
// Verify state
KMP_DEBUG_ASSERT(__kmp_threads && __kmp_threads[gtid]);
KMP_DEBUG_ASSERT(TCR_PTR(this_thr->th.th_team));
KMP_DEBUG_ASSERT(TCR_PTR(this_thr->th.th_root));
KMP_DEBUG_ASSERT(this_thr == team->t.t_threads[tid]);
KA_TRACE(10, ("__kmp_join_barrier: T#%d(%d:%d) arrived at join barrier\n",
gtid, team_id, tid));
ANNOTATE_BARRIER_BEGIN(&team->t.t_bar);
#if OMPT_SUPPORT
ompt_data_t *my_task_data;
ompt_data_t *my_parallel_data;
if (ompt_enabled.enabled) {
#if OMPT_OPTIONAL
void *codeptr = NULL;
int ds_tid = this_thr->th.th_info.ds.ds_tid;
if (KMP_MASTER_TID(ds_tid) &&
(ompt_callbacks.ompt_callback(ompt_callback_sync_region_wait) ||
ompt_callbacks.ompt_callback(ompt_callback_sync_region)))
codeptr = team->t.ompt_team_info.master_return_address;
my_task_data = OMPT_CUR_TASK_DATA(this_thr);
my_parallel_data = OMPT_CUR_TEAM_DATA(this_thr);
if (ompt_enabled.ompt_callback_sync_region) {
ompt_callbacks.ompt_callback(ompt_callback_sync_region)(
ompt_sync_region_barrier, ompt_scope_begin, my_parallel_data,
my_task_data, codeptr);
}
if (ompt_enabled.ompt_callback_sync_region_wait) {
ompt_callbacks.ompt_callback(ompt_callback_sync_region_wait)(
ompt_sync_region_barrier, ompt_scope_begin, my_parallel_data,
my_task_data, codeptr);
}
if (!KMP_MASTER_TID(ds_tid))
this_thr->th.ompt_thread_info.task_data = *OMPT_CUR_TASK_DATA(this_thr);
#endif
this_thr->th.ompt_thread_info.state = omp_state_wait_barrier_implicit;
}
#endif
if (__kmp_tasking_mode == tskm_extra_barrier) {
__kmp_tasking_barrier(team, this_thr, gtid);
KA_TRACE(10, ("__kmp_join_barrier: T#%d(%d:%d) past taking barrier\n", gtid,
team_id, tid));
}
#ifdef KMP_DEBUG
if (__kmp_tasking_mode != tskm_immediate_exec) {
KA_TRACE(20, ("__kmp_join_barrier: T#%d, old team = %d, old task_team = "
"%p, th_task_team = %p\n",
__kmp_gtid_from_thread(this_thr), team_id,
team->t.t_task_team[this_thr->th.th_task_state],
this_thr->th.th_task_team));
KMP_DEBUG_ASSERT(this_thr->th.th_task_team ==
team->t.t_task_team[this_thr->th.th_task_state]);
}
#endif /* KMP_DEBUG */
/* Copy the blocktime info to the thread, where __kmp_wait_template() can
access it when the team struct is not guaranteed to exist. Doing these
loads causes a cache miss slows down EPCC parallel by 2x. As a workaround,
we do not perform the copy if blocktime=infinite, since the values are not
used by __kmp_wait_template() in that case. */
if (__kmp_dflt_blocktime != KMP_MAX_BLOCKTIME) {
#if KMP_USE_MONITOR
this_thr->th.th_team_bt_intervals =
team->t.t_implicit_task_taskdata[tid].td_icvs.bt_intervals;
this_thr->th.th_team_bt_set =
team->t.t_implicit_task_taskdata[tid].td_icvs.bt_set;
#else
this_thr->th.th_team_bt_intervals = KMP_BLOCKTIME_INTERVAL(team, tid);
#endif
}
#if USE_ITT_BUILD
if (__itt_sync_create_ptr || KMP_ITT_DEBUG)
__kmp_itt_barrier_starting(gtid, itt_sync_obj);
#endif /* USE_ITT_BUILD */
switch (__kmp_barrier_gather_pattern[bs_forkjoin_barrier]) {
case bp_hyper_bar: {
KMP_ASSERT(__kmp_barrier_gather_branch_bits[bs_forkjoin_barrier]);
__kmp_hyper_barrier_gather(bs_forkjoin_barrier, this_thr, gtid, tid,
NULL USE_ITT_BUILD_ARG(itt_sync_obj));
break;
}
case bp_hierarchical_bar: {
__kmp_hierarchical_barrier_gather(bs_forkjoin_barrier, this_thr, gtid, tid,
NULL USE_ITT_BUILD_ARG(itt_sync_obj));
break;
}
case bp_tree_bar: {
KMP_ASSERT(__kmp_barrier_gather_branch_bits[bs_forkjoin_barrier]);
__kmp_tree_barrier_gather(bs_forkjoin_barrier, this_thr, gtid, tid,
NULL USE_ITT_BUILD_ARG(itt_sync_obj));
break;
}
default: {
__kmp_linear_barrier_gather(bs_forkjoin_barrier, this_thr, gtid, tid,
NULL USE_ITT_BUILD_ARG(itt_sync_obj));
}
}
/* From this point on, the team data structure may be deallocated at any time
by the master thread - it is unsafe to reference it in any of the worker
threads. Any per-team data items that need to be referenced before the
end of the barrier should be moved to the kmp_task_team_t structs. */
if (KMP_MASTER_TID(tid)) {
if (__kmp_tasking_mode != tskm_immediate_exec) {
__kmp_task_team_wait(this_thr, team USE_ITT_BUILD_ARG(itt_sync_obj));
}
#if KMP_STATS_ENABLED
// Have master thread flag the workers to indicate they are now waiting for
// next parallel region, Also wake them up so they switch their timers to
// idle.
for (int i = 0; i < team->t.t_nproc; ++i) {
kmp_info_t *team_thread = team->t.t_threads[i];
if (team_thread == this_thr)
continue;
team_thread->th.th_stats->setIdleFlag();
if (__kmp_dflt_blocktime != KMP_MAX_BLOCKTIME &&
team_thread->th.th_sleep_loc != NULL)
__kmp_null_resume_wrapper(__kmp_gtid_from_thread(team_thread),
team_thread->th.th_sleep_loc);
}
#endif
#if USE_ITT_BUILD
if (__itt_sync_create_ptr || KMP_ITT_DEBUG)
__kmp_itt_barrier_middle(gtid, itt_sync_obj);
#endif /* USE_ITT_BUILD */
#if USE_ITT_BUILD && USE_ITT_NOTIFY
// Join barrier - report frame end
if ((__itt_frame_submit_v3_ptr || KMP_ITT_DEBUG) &&
__kmp_forkjoin_frames_mode &&
#if OMP_40_ENABLED
this_thr->th.th_teams_microtask == NULL &&
#endif
team->t.t_active_level == 1) {
kmp_uint64 cur_time = __itt_get_timestamp();
ident_t *loc = team->t.t_ident;
kmp_info_t **other_threads = team->t.t_threads;
int nproc = this_thr->th.th_team_nproc;
int i;
switch (__kmp_forkjoin_frames_mode) {
case 1:
__kmp_itt_frame_submit(gtid, this_thr->th.th_frame_time, cur_time, 0,
loc, nproc);
break;
case 2:
__kmp_itt_frame_submit(gtid, this_thr->th.th_bar_min_time, cur_time, 1,
loc, nproc);
break;
case 3:
if (__itt_metadata_add_ptr) {
// Initialize with master's wait time
kmp_uint64 delta = cur_time - this_thr->th.th_bar_arrive_time;
// Set arrive time to zero to be able to check it in
// __kmp_invoke_task(); the same is done inside the loop below
this_thr->th.th_bar_arrive_time = 0;
for (i = 1; i < nproc; ++i) {
delta += (cur_time - other_threads[i]->th.th_bar_arrive_time);
other_threads[i]->th.th_bar_arrive_time = 0;
}
__kmp_itt_metadata_imbalance(gtid, this_thr->th.th_frame_time,
cur_time, delta, 0);
}
__kmp_itt_frame_submit(gtid, this_thr->th.th_frame_time, cur_time, 0,
loc, nproc);
this_thr->th.th_frame_time = cur_time;
break;
}
}
#endif /* USE_ITT_BUILD */
}
#if USE_ITT_BUILD
else {
if (__itt_sync_create_ptr || KMP_ITT_DEBUG)
__kmp_itt_barrier_middle(gtid, itt_sync_obj);
}
#endif /* USE_ITT_BUILD */
#if KMP_DEBUG
if (KMP_MASTER_TID(tid)) {
KA_TRACE(
15,
("__kmp_join_barrier: T#%d(%d:%d) says all %d team threads arrived\n",
gtid, team_id, tid, nproc));
}
#endif /* KMP_DEBUG */
// TODO now, mark worker threads as done so they may be disbanded
KMP_MB(); // Flush all pending memory write invalidates.
KA_TRACE(10,
("__kmp_join_barrier: T#%d(%d:%d) leaving\n", gtid, team_id, tid));
ANNOTATE_BARRIER_END(&team->t.t_bar);
}
// TODO release worker threads' fork barriers as we are ready instead of all at
// once
void __kmp_fork_barrier(int gtid, int tid) {
KMP_TIME_PARTITIONED_BLOCK(OMP_fork_barrier);
KMP_SET_THREAD_STATE_BLOCK(FORK_JOIN_BARRIER);
kmp_info_t *this_thr = __kmp_threads[gtid];
kmp_team_t *team = (tid == 0) ? this_thr->th.th_team : NULL;
#if USE_ITT_BUILD
void *itt_sync_obj = NULL;
#endif /* USE_ITT_BUILD */
if (team)
ANNOTATE_BARRIER_END(&team->t.t_bar);
KA_TRACE(10, ("__kmp_fork_barrier: T#%d(%d:%d) has arrived\n", gtid,
(team != NULL) ? team->t.t_id : -1, tid));
// th_team pointer only valid for master thread here
if (KMP_MASTER_TID(tid)) {
#if USE_ITT_BUILD && USE_ITT_NOTIFY
if (__itt_sync_create_ptr || KMP_ITT_DEBUG) {
// Create itt barrier object
itt_sync_obj = __kmp_itt_barrier_object(gtid, bs_forkjoin_barrier, 1);
__kmp_itt_barrier_middle(gtid, itt_sync_obj); // Call acquired/releasing
}
#endif /* USE_ITT_BUILD && USE_ITT_NOTIFY */
#ifdef KMP_DEBUG
kmp_info_t **other_threads = team->t.t_threads;
int i;
// Verify state
KMP_MB();
for (i = 1; i < team->t.t_nproc; ++i) {
KA_TRACE(500,
("__kmp_fork_barrier: T#%d(%d:0) checking T#%d(%d:%d) fork go "
"== %u.\n",
gtid, team->t.t_id, other_threads[i]->th.th_info.ds.ds_gtid,
team->t.t_id, other_threads[i]->th.th_info.ds.ds_tid,
other_threads[i]->th.th_bar[bs_forkjoin_barrier].bb.b_go));
KMP_DEBUG_ASSERT(
(TCR_4(other_threads[i]->th.th_bar[bs_forkjoin_barrier].bb.b_go) &
~(KMP_BARRIER_SLEEP_STATE)) == KMP_INIT_BARRIER_STATE);
KMP_DEBUG_ASSERT(other_threads[i]->th.th_team == team);
}
#endif
if (__kmp_tasking_mode != tskm_immediate_exec) {
// 0 indicates setup current task team if nthreads > 1
__kmp_task_team_setup(this_thr, team, 0);
}
/* The master thread may have changed its blocktime between the join barrier
and the fork barrier. Copy the blocktime info to the thread, where
__kmp_wait_template() can access it when the team struct is not
guaranteed to exist. */
// See note about the corresponding code in __kmp_join_barrier() being
// performance-critical
if (__kmp_dflt_blocktime != KMP_MAX_BLOCKTIME) {
#if KMP_USE_MONITOR
this_thr->th.th_team_bt_intervals =
team->t.t_implicit_task_taskdata[tid].td_icvs.bt_intervals;
this_thr->th.th_team_bt_set =
team->t.t_implicit_task_taskdata[tid].td_icvs.bt_set;
#else
this_thr->th.th_team_bt_intervals = KMP_BLOCKTIME_INTERVAL(team, tid);
#endif
}
} // master
switch (__kmp_barrier_release_pattern[bs_forkjoin_barrier]) {
case bp_hyper_bar: {
KMP_ASSERT(__kmp_barrier_release_branch_bits[bs_forkjoin_barrier]);
__kmp_hyper_barrier_release(bs_forkjoin_barrier, this_thr, gtid, tid,
TRUE USE_ITT_BUILD_ARG(itt_sync_obj));
break;
}
case bp_hierarchical_bar: {
__kmp_hierarchical_barrier_release(bs_forkjoin_barrier, this_thr, gtid, tid,
TRUE USE_ITT_BUILD_ARG(itt_sync_obj));
break;
}
case bp_tree_bar: {
KMP_ASSERT(__kmp_barrier_release_branch_bits[bs_forkjoin_barrier]);
__kmp_tree_barrier_release(bs_forkjoin_barrier, this_thr, gtid, tid,
TRUE USE_ITT_BUILD_ARG(itt_sync_obj));
break;
}
default: {
__kmp_linear_barrier_release(bs_forkjoin_barrier, this_thr, gtid, tid,
TRUE USE_ITT_BUILD_ARG(itt_sync_obj));
}
}
#if OMPT_SUPPORT
if (ompt_enabled.enabled &&
this_thr->th.ompt_thread_info.state == omp_state_wait_barrier_implicit) {
int ds_tid = this_thr->th.th_info.ds.ds_tid;
ompt_data_t *task_data = (team)
? OMPT_CUR_TASK_DATA(this_thr)
: &(this_thr->th.ompt_thread_info.task_data);
this_thr->th.ompt_thread_info.state = omp_state_overhead;
#if OMPT_OPTIONAL
void *codeptr = NULL;
if (KMP_MASTER_TID(ds_tid) &&
(ompt_callbacks.ompt_callback(ompt_callback_sync_region_wait) ||
ompt_callbacks.ompt_callback(ompt_callback_sync_region)))
codeptr = team->t.ompt_team_info.master_return_address;
if (ompt_enabled.ompt_callback_sync_region_wait) {
ompt_callbacks.ompt_callback(ompt_callback_sync_region_wait)(
ompt_sync_region_barrier, ompt_scope_end, NULL, task_data, codeptr);
}
if (ompt_enabled.ompt_callback_sync_region) {
ompt_callbacks.ompt_callback(ompt_callback_sync_region)(
ompt_sync_region_barrier, ompt_scope_end, NULL, task_data, codeptr);
}
#endif
if (!KMP_MASTER_TID(ds_tid) && ompt_enabled.ompt_callback_implicit_task) {
ompt_callbacks.ompt_callback(ompt_callback_implicit_task)(
ompt_scope_end, NULL, task_data, 0, ds_tid);
}
}
#endif
// Early exit for reaping threads releasing forkjoin barrier
if (TCR_4(__kmp_global.g.g_done)) {
this_thr->th.th_task_team = NULL;
#if USE_ITT_BUILD && USE_ITT_NOTIFY
if (__itt_sync_create_ptr || KMP_ITT_DEBUG) {
if (!KMP_MASTER_TID(tid)) {
itt_sync_obj = __kmp_itt_barrier_object(gtid, bs_forkjoin_barrier);
if (itt_sync_obj)
__kmp_itt_barrier_finished(gtid, itt_sync_obj);
}
}
#endif /* USE_ITT_BUILD && USE_ITT_NOTIFY */
KA_TRACE(10, ("__kmp_fork_barrier: T#%d is leaving early\n", gtid));
return;
}
/* We can now assume that a valid team structure has been allocated by the
master and propagated to all worker threads. The current thread, however,
may not be part of the team, so we can't blindly assume that the team
pointer is non-null. */
team = (kmp_team_t *)TCR_PTR(this_thr->th.th_team);
KMP_DEBUG_ASSERT(team != NULL);
tid = __kmp_tid_from_gtid(gtid);
#if KMP_BARRIER_ICV_PULL
/* Master thread's copy of the ICVs was set up on the implicit taskdata in
__kmp_reinitialize_team. __kmp_fork_call() assumes the master thread's
implicit task has this data before this function is called. We cannot
modify __kmp_fork_call() to look at the fixed ICVs in the master's thread
struct, because it is not always the case that the threads arrays have
been allocated when __kmp_fork_call() is executed. */
{
KMP_TIME_DEVELOPER_PARTITIONED_BLOCK(USER_icv_copy);
if (!KMP_MASTER_TID(tid)) { // master thread already has ICVs
// Copy the initial ICVs from the master's thread struct to the implicit
// task for this tid.
KA_TRACE(10,
("__kmp_fork_barrier: T#%d(%d) is PULLing ICVs\n", gtid, tid));
__kmp_init_implicit_task(team->t.t_ident, team->t.t_threads[tid], team,
tid, FALSE);
copy_icvs(&team->t.t_implicit_task_taskdata[tid].td_icvs,
&team->t.t_threads[0]
->th.th_bar[bs_forkjoin_barrier]
.bb.th_fixed_icvs);
}
}
#endif // KMP_BARRIER_ICV_PULL
if (__kmp_tasking_mode != tskm_immediate_exec) {
__kmp_task_team_sync(this_thr, team);
}
#if OMP_40_ENABLED && KMP_AFFINITY_SUPPORTED
kmp_proc_bind_t proc_bind = team->t.t_proc_bind;
if (proc_bind == proc_bind_intel) {
#endif
#if KMP_AFFINITY_SUPPORTED
// Call dynamic affinity settings
if (__kmp_affinity_type == affinity_balanced && team->t.t_size_changed) {
__kmp_balanced_affinity(tid, team->t.t_nproc);
}
#endif // KMP_AFFINITY_SUPPORTED
#if OMP_40_ENABLED && KMP_AFFINITY_SUPPORTED
} else if (proc_bind != proc_bind_false) {
if (this_thr->th.th_new_place == this_thr->th.th_current_place) {
KA_TRACE(100, ("__kmp_fork_barrier: T#%d already in correct place %d\n",
__kmp_gtid_from_thread(this_thr),
this_thr->th.th_current_place));
} else {
__kmp_affinity_set_place(gtid);
}
}
#endif
#if USE_ITT_BUILD && USE_ITT_NOTIFY
if (__itt_sync_create_ptr || KMP_ITT_DEBUG) {
if (!KMP_MASTER_TID(tid)) {
// Get correct barrier object
itt_sync_obj = __kmp_itt_barrier_object(gtid, bs_forkjoin_barrier);
__kmp_itt_barrier_finished(gtid, itt_sync_obj); // Workers call acquired
} // (prepare called inside barrier_release)
}
#endif /* USE_ITT_BUILD && USE_ITT_NOTIFY */
ANNOTATE_BARRIER_END(&team->t.t_bar);
KA_TRACE(10, ("__kmp_fork_barrier: T#%d(%d:%d) is leaving\n", gtid,
team->t.t_id, tid));
}
void __kmp_setup_icv_copy(kmp_team_t *team, int new_nproc,
kmp_internal_control_t *new_icvs, ident_t *loc) {
KMP_TIME_DEVELOPER_PARTITIONED_BLOCK(KMP_setup_icv_copy);
KMP_DEBUG_ASSERT(team && new_nproc && new_icvs);
KMP_DEBUG_ASSERT((!TCR_4(__kmp_init_parallel)) || new_icvs->nproc);
/* Master thread's copy of the ICVs was set up on the implicit taskdata in
__kmp_reinitialize_team. __kmp_fork_call() assumes the master thread's
implicit task has this data before this function is called. */
#if KMP_BARRIER_ICV_PULL
/* Copy ICVs to master's thread structure into th_fixed_icvs (which remains
untouched), where all of the worker threads can access them and make their
own copies after the barrier. */
KMP_DEBUG_ASSERT(team->t.t_threads[0]); // The threads arrays should be
// allocated at this point
copy_icvs(
&team->t.t_threads[0]->th.th_bar[bs_forkjoin_barrier].bb.th_fixed_icvs,
new_icvs);
KF_TRACE(10, ("__kmp_setup_icv_copy: PULL: T#%d this_thread=%p team=%p\n", 0,
team->t.t_threads[0], team));
#elif KMP_BARRIER_ICV_PUSH
// The ICVs will be propagated in the fork barrier, so nothing needs to be
// done here.
KF_TRACE(10, ("__kmp_setup_icv_copy: PUSH: T#%d this_thread=%p team=%p\n", 0,
team->t.t_threads[0], team));
#else
// Copy the ICVs to each of the non-master threads. This takes O(nthreads)
// time.
ngo_load(new_icvs);
KMP_DEBUG_ASSERT(team->t.t_threads[0]); // The threads arrays should be
// allocated at this point
for (int f = 1; f < new_nproc; ++f) { // Skip the master thread
// TODO: GEH - pass in better source location info since usually NULL here
KF_TRACE(10, ("__kmp_setup_icv_copy: LINEAR: T#%d this_thread=%p team=%p\n",
f, team->t.t_threads[f], team));
__kmp_init_implicit_task(loc, team->t.t_threads[f], team, f, FALSE);
ngo_store_icvs(&team->t.t_implicit_task_taskdata[f].td_icvs, new_icvs);
KF_TRACE(10, ("__kmp_setup_icv_copy: LINEAR: T#%d this_thread=%p team=%p\n",
f, team->t.t_threads[f], team));
}
ngo_sync();
#endif // KMP_BARRIER_ICV_PULL
}
ident
Definition: kmp.h:207