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Fix hanging barriers if number of parallel regions exceeds UINT_MAX
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The fix is to make b_arrived flag 64 bit in both structures - kmp_balign_team_t
and kmp_balign_t. Otherwise when flag in kmp_balign_team_t wrapped over
UINT_MAX the library hangs.

Differential Revision: http://reviews.llvm.org/D12563

llvm-svn: 247320
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@jpeyton52
jpeyton52 committed Sep 10, 2015
1 parent 6ec370a commit d26e213
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Showing 4 changed files with 24 additions and 24 deletions.
2 changes: 1 addition & 1 deletion openmp/runtime/src/kmp.h
View file
Expand Up @@ -1680,7 +1680,7 @@ union KMP_ALIGN_CACHE kmp_barrier_team_union {
double b_align; /* use worst case alignment */
char b_pad[ CACHE_LINE ];
struct {
kmp_uint b_arrived; /* STATE => task reached synch point. */
kmp_uint64 b_arrived; /* STATE => task reached synch point. */
#if USE_DEBUGGER
// The following two fields are indended for the debugger solely. Only master of the team accesses
// these fields: the first one is increased by 1 when master arrives to a barrier, the
Expand Down
38 changes: 19 additions & 19 deletions openmp/runtime/src/kmp_barrier.cpp
View file
Expand Up @@ -64,7 +64,7 @@ __kmp_linear_barrier_gather(enum barrier_type bt, kmp_info_t *this_thr, int gtid
// 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): %u => %u\n", gtid, team->t.t_id, tid,
"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
Expand All @@ -77,7 +77,7 @@ __kmp_linear_barrier_gather(enum barrier_type bt, kmp_info_t *this_thr, int gtid
register int nproc = this_thr->th.th_team_nproc;
register int i;
// Don't have to worry about sleep bit here or atomic since team setting
register kmp_uint new_state = team_bar->b_arrived + KMP_BARRIER_STATE_BUMP;
register 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) {
Expand All @@ -87,7 +87,7 @@ __kmp_linear_barrier_gather(enum barrier_type bt, kmp_info_t *this_thr, int gtid
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) == %u\n", gtid, team->t.t_id, tid,
"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));

Expand All @@ -111,7 +111,7 @@ __kmp_linear_barrier_gather(enum barrier_type bt, kmp_info_t *this_thr, int gtid
}
// 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) = %u\n",
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",
Expand Down Expand Up @@ -227,7 +227,7 @@ __kmp_tree_barrier_gather(enum barrier_type bt, kmp_info_t *this_thr, int gtid,
register kmp_uint32 branch_factor = 1 << branch_bits;
register kmp_uint32 child;
register kmp_uint32 child_tid;
register kmp_uint new_state;
register 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));
Expand All @@ -254,7 +254,7 @@ __kmp_tree_barrier_gather(enum barrier_type bt, kmp_info_t *this_thr, int gtid,
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) == %u\n", gtid, team->t.t_id, tid,
"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
Expand Down Expand Up @@ -284,7 +284,7 @@ __kmp_tree_barrier_gather(enum barrier_type bt, kmp_info_t *this_thr, int gtid,
register 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): %u => %u\n", gtid, team->t.t_id, tid,
"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));
Expand All @@ -300,7 +300,7 @@ __kmp_tree_barrier_gather(enum barrier_type bt, kmp_info_t *this_thr, int gtid,
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) = %u\n",
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));
}
Expand Down Expand Up @@ -420,7 +420,7 @@ __kmp_hyper_barrier_gather(enum barrier_type bt, kmp_info_t *this_thr, int gtid,
register kmp_team_t *team = this_thr->th.th_team;
register kmp_bstate_t *thr_bar = &this_thr->th.th_bar[bt].bb;
register kmp_info_t **other_threads = team->t.t_threads;
register kmp_uint new_state = KMP_BARRIER_UNUSED_STATE;
register kmp_uint64 new_state = KMP_BARRIER_UNUSED_STATE;
register kmp_uint32 num_threads = this_thr->th.th_team_nproc;
register kmp_uint32 branch_bits = __kmp_barrier_gather_branch_bits[bt];
register kmp_uint32 branch_factor = 1 << branch_bits;
Expand Down Expand Up @@ -450,7 +450,7 @@ __kmp_hyper_barrier_gather(enum barrier_type bt, kmp_info_t *this_thr, int gtid,
register 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): %u => %u\n", gtid, team->t.t_id, tid,
"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));
Expand Down Expand Up @@ -478,7 +478,7 @@ __kmp_hyper_barrier_gather(enum barrier_type bt, kmp_info_t *this_thr, int gtid,
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) == %u\n", gtid, team->t.t_id, tid,
"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
Expand Down Expand Up @@ -507,7 +507,7 @@ __kmp_hyper_barrier_gather(enum barrier_type bt, kmp_info_t *this_thr, int gtid,
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) = %u\n",
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));
}
Expand Down Expand Up @@ -759,7 +759,7 @@ __kmp_hierarchical_barrier_gather(enum barrier_type bt, kmp_info_t *this_thr,
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 : (kmp_uint64)team->t.t_bar[bt].b_arrived | thr_bar->leaf_state;
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;
kmp_flag_64 flag(&thr_bar->b_arrived, leaf_state);
flag.wait(this_thr, FALSE
USE_ITT_BUILD_ARG(itt_sync_obj) );
Expand All @@ -781,7 +781,7 @@ __kmp_hierarchical_barrier_gather(enum barrier_type bt, kmp_info_t *this_thr,
register kmp_info_t *child_thr = other_threads[child_tid];
register 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) == %u\n",
"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);
Expand All @@ -804,7 +804,7 @@ __kmp_hierarchical_barrier_gather(enum barrier_type bt, kmp_info_t *this_thr,
register kmp_info_t *child_thr = other_threads[child_tid];
register 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) == %u\n",
"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);
Expand All @@ -824,7 +824,7 @@ __kmp_hierarchical_barrier_gather(enum barrier_type bt, kmp_info_t *this_thr,

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): %u => %u\n", gtid, team->t.t_id, tid,
"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
Expand All @@ -835,14 +835,14 @@ __kmp_hierarchical_barrier_gather(enum barrier_type bt, kmp_info_t *this_thr,
flag.release();
}
else { // Leaf does special release on the "offset" bits of parent's b_arrived flag
thr_bar->b_arrived = (kmp_uint64)team->t.t_bar[bt].b_arrived + KMP_BARRIER_STATE_BUMP;
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 = (kmp_uint32)new_state;
KA_TRACE(20, ("__kmp_hierarchical_barrier_gather: T#%d(%d:%d) set team %d arrived(%p) = %u\n",
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?
Expand Down
4 changes: 2 additions & 2 deletions openmp/runtime/src/kmp_itt.inl
View file
Expand Up @@ -483,7 +483,7 @@ __kmp_itt_barrier_object(

// Master thread increases b_arrived by KMP_BARRIER_STATE_BUMP each time. Divide b_arrived
// by KMP_BARRIER_STATE_BUMP to get plain barrier counter.
kmp_uint counter = team->t.t_bar[ bt ].b_arrived / KMP_BARRIER_STATE_BUMP + delta;
kmp_uint64 counter = team->t.t_bar[ bt ].b_arrived / KMP_BARRIER_STATE_BUMP + delta;
// Now form the barrier id. Encode barrier type (bt) in barrier id too, so barriers of
// different types do not have the same ids.
KMP_BUILD_ASSERT( sizeof( kmp_team_t ) >= bs_last_barrier );
Expand All @@ -498,7 +498,7 @@ __kmp_itt_barrier_object(
+ bt
);
KMP_ITT_DEBUG_LOCK();
KMP_ITT_DEBUG_PRINT( "[bar obj] type=%d, counter=%d, object=%p\n", bt, counter, object );
KMP_ITT_DEBUG_PRINT( "[bar obj] type=%d, counter=%lld, object=%p\n", bt, counter, object );

if ( set_name ) {
ident_t const * loc = NULL;
Expand Down
4 changes: 2 additions & 2 deletions openmp/runtime/src/kmp_runtime.c
View file
Expand Up @@ -1102,7 +1102,7 @@ __kmp_fork_team_threads( kmp_root_t *root, kmp_team_t *team,
KMP_DEBUG_ASSERT( thr );
KMP_DEBUG_ASSERT( thr->th.th_team == team );
/* align team and thread arrived states */
KA_TRACE( 20, ("__kmp_fork_team_threads: T#%d(%d:%d) init arrived T#%d(%d:%d) join =%u, plain=%u\n",
KA_TRACE( 20, ("__kmp_fork_team_threads: T#%d(%d:%d) init arrived T#%d(%d:%d) join =%llu, plain=%llu\n",
__kmp_gtid_from_tid( 0, team ), team->t.t_id, 0,
__kmp_gtid_from_tid( i, team ), team->t.t_id, i,
team->t.t_bar[ bs_forkjoin_barrier ].b_arrived,
Expand Down Expand Up @@ -5050,7 +5050,7 @@ __kmp_allocate_team( kmp_root_t *root, int new_nproc, int max_nproc,
KMP_DEBUG_ASSERT( new_worker );
team->t.t_threads[ f ] = new_worker;

KA_TRACE( 20, ("__kmp_allocate_team: team %d init T#%d arrived: join=%u, plain=%u\n",
KA_TRACE( 20, ("__kmp_allocate_team: team %d init T#%d arrived: join=%llu, plain=%llu\n",
team->t.t_id, __kmp_gtid_from_tid( f, team ), team->t.t_id, f,
team->t.t_bar[bs_forkjoin_barrier].b_arrived,
team->t.t_bar[bs_plain_barrier].b_arrived ) );
Expand Down

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