kmp_dispatch_hier.h
/*
* kmp_dispatch_hier.h -- hierarchical scheduling methods and data structures
*/
//===----------------------------------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
#ifndef KMP_DISPATCH_HIER_H
#define KMP_DISPATCH_HIER_H
#include "kmp.h"
#include "kmp_dispatch.h"
// Layer type for scheduling hierarchy
enum kmp_hier_layer_e {
LAYER_THREAD = -1,
LAYER_L1,
LAYER_L2,
LAYER_L3,
LAYER_NUMA,
LAYER_LOOP,
LAYER_LAST
};
// Convert hierarchy type (LAYER_L1, LAYER_L2, etc.) to C-style string
static inline const char *__kmp_get_hier_str(kmp_hier_layer_e type) {
switch (type) {
case kmp_hier_layer_e::LAYER_THREAD:
return "THREAD";
case kmp_hier_layer_e::LAYER_L1:
return "L1";
case kmp_hier_layer_e::LAYER_L2:
return "L2";
case kmp_hier_layer_e::LAYER_L3:
return "L3";
case kmp_hier_layer_e::LAYER_NUMA:
return "NUMA";
case kmp_hier_layer_e::LAYER_LOOP:
return "WHOLE_LOOP";
case kmp_hier_layer_e::LAYER_LAST:
return "LAST";
}
KMP_ASSERT(0);
// Appease compilers, should never get here
return "ERROR";
}
// Structure to store values parsed from OMP_SCHEDULE for scheduling hierarchy
typedef struct kmp_hier_sched_env_t {
int size;
int capacity;
enum sched_type *scheds;
kmp_int32 *small_chunks;
kmp_int64 *large_chunks;
kmp_hier_layer_e *layers;
// Append a level of the hierarchy
void append(enum sched_type sched, kmp_int32 chunk, kmp_hier_layer_e layer) {
if (capacity == 0) {
scheds = (enum sched_type *)__kmp_allocate(sizeof(enum sched_type) *
kmp_hier_layer_e::LAYER_LAST);
small_chunks = (kmp_int32 *)__kmp_allocate(sizeof(kmp_int32) *
kmp_hier_layer_e::LAYER_LAST);
large_chunks = (kmp_int64 *)__kmp_allocate(sizeof(kmp_int64) *
kmp_hier_layer_e::LAYER_LAST);
layers = (kmp_hier_layer_e *)__kmp_allocate(sizeof(kmp_hier_layer_e) *
kmp_hier_layer_e::LAYER_LAST);
capacity = kmp_hier_layer_e::LAYER_LAST;
}
int current_size = size;
KMP_DEBUG_ASSERT(current_size < kmp_hier_layer_e::LAYER_LAST);
scheds[current_size] = sched;
layers[current_size] = layer;
small_chunks[current_size] = chunk;
large_chunks[current_size] = (kmp_int64)chunk;
size++;
}
// Sort the hierarchy using selection sort, size will always be small
// (less than LAYER_LAST) so it is not necessary to use an nlog(n) algorithm
void sort() {
if (size <= 1)
return;
for (int i = 0; i < size; ++i) {
int switch_index = i;
for (int j = i + 1; j < size; ++j) {
if (layers[j] < layers[switch_index])
switch_index = j;
}
if (switch_index != i) {
kmp_hier_layer_e temp1 = layers[i];
enum sched_type temp2 = scheds[i];
kmp_int32 temp3 = small_chunks[i];
kmp_int64 temp4 = large_chunks[i];
layers[i] = layers[switch_index];
scheds[i] = scheds[switch_index];
small_chunks[i] = small_chunks[switch_index];
large_chunks[i] = large_chunks[switch_index];
layers[switch_index] = temp1;
scheds[switch_index] = temp2;
small_chunks[switch_index] = temp3;
large_chunks[switch_index] = temp4;
}
}
}
// Free all memory
void deallocate() {
if (capacity > 0) {
__kmp_free(scheds);
__kmp_free(layers);
__kmp_free(small_chunks);
__kmp_free(large_chunks);
scheds = NULL;
layers = NULL;
small_chunks = NULL;
large_chunks = NULL;
}
size = 0;
capacity = 0;
}
} kmp_hier_sched_env_t;
extern int __kmp_dispatch_hand_threading;
extern kmp_hier_sched_env_t __kmp_hier_scheds;
// Sizes of layer arrays bounded by max number of detected L1s, L2s, etc.
extern int __kmp_hier_max_units[kmp_hier_layer_e::LAYER_LAST + 1];
extern int __kmp_hier_threads_per[kmp_hier_layer_e::LAYER_LAST + 1];
extern int __kmp_dispatch_get_index(int tid, kmp_hier_layer_e type);
extern int __kmp_dispatch_get_id(int gtid, kmp_hier_layer_e type);
extern int __kmp_dispatch_get_t1_per_t2(kmp_hier_layer_e t1,
kmp_hier_layer_e t2);
extern void __kmp_dispatch_free_hierarchies(kmp_team_t *team);
template <typename T> struct kmp_hier_shared_bdata_t {
typedef typename traits_t<T>::signed_t ST;
volatile kmp_uint64 val[2];
kmp_int32 status[2];
T lb[2];
T ub[2];
ST st[2];
dispatch_shared_info_template<T> sh[2];
void zero() {
val[0] = val[1] = 0;
status[0] = status[1] = 0;
lb[0] = lb[1] = 0;
ub[0] = ub[1] = 0;
st[0] = st[1] = 0;
sh[0].u.s.iteration = sh[1].u.s.iteration = 0;
}
void set_next_hand_thread(T nlb, T nub, ST nst, kmp_int32 nstatus,
kmp_uint64 index) {
lb[1 - index] = nlb;
ub[1 - index] = nub;
st[1 - index] = nst;
status[1 - index] = nstatus;
}
void set_next(T nlb, T nub, ST nst, kmp_int32 nstatus, kmp_uint64 index) {
lb[1 - index] = nlb;
ub[1 - index] = nub;
st[1 - index] = nst;
status[1 - index] = nstatus;
sh[1 - index].u.s.iteration = 0;
}
kmp_int32 get_next_status(kmp_uint64 index) const {
return status[1 - index];
}
T get_next_lb(kmp_uint64 index) const { return lb[1 - index]; }
T get_next_ub(kmp_uint64 index) const { return ub[1 - index]; }
ST get_next_st(kmp_uint64 index) const { return st[1 - index]; }
dispatch_shared_info_template<T> volatile *get_next_sh(kmp_uint64 index) {
return &(sh[1 - index]);
}
kmp_int32 get_curr_status(kmp_uint64 index) const { return status[index]; }
T get_curr_lb(kmp_uint64 index) const { return lb[index]; }
T get_curr_ub(kmp_uint64 index) const { return ub[index]; }
ST get_curr_st(kmp_uint64 index) const { return st[index]; }
dispatch_shared_info_template<T> volatile *get_curr_sh(kmp_uint64 index) {
return &(sh[index]);
}
};
/*
* In the barrier implementations, num_active is the number of threads that are
* attached to the kmp_hier_top_unit_t structure in the scheduling hierarchy.
* bdata is the shared barrier data that resides on the kmp_hier_top_unit_t
* structure. tdata is the thread private data that resides on the thread
* data structure.
*
* The reset_shared() method is used to initialize the barrier data on the
* kmp_hier_top_unit_t hierarchy structure
*
* The reset_private() method is used to initialize the barrier data on the
* thread's private dispatch buffer structure
*
* The barrier() method takes an id, which is that thread's id for the
* kmp_hier_top_unit_t structure, and implements the barrier. All threads wait
* inside barrier() until all fellow threads who are attached to that
* kmp_hier_top_unit_t structure have arrived.
*/
// Core barrier implementation
// Can be used in a unit with between 2 to 8 threads
template <typename T> class core_barrier_impl {
static inline kmp_uint64 get_wait_val(int num_active) {
kmp_uint64 wait_val = 0LL;
switch (num_active) {
case 2:
wait_val = 0x0101LL;
break;
case 3:
wait_val = 0x010101LL;
break;
case 4:
wait_val = 0x01010101LL;
break;
case 5:
wait_val = 0x0101010101LL;
break;
case 6:
wait_val = 0x010101010101LL;
break;
case 7:
wait_val = 0x01010101010101LL;
break;
case 8:
wait_val = 0x0101010101010101LL;
break;
default:
// don't use the core_barrier_impl for more than 8 threads
KMP_ASSERT(0);
}
return wait_val;
}
public:
static void reset_private(kmp_int32 num_active,
kmp_hier_private_bdata_t *tdata);
static void reset_shared(kmp_int32 num_active,
kmp_hier_shared_bdata_t<T> *bdata);
static void barrier(kmp_int32 id, kmp_hier_shared_bdata_t<T> *bdata,
kmp_hier_private_bdata_t *tdata);
};
template <typename T>
void core_barrier_impl<T>::reset_private(kmp_int32 num_active,
kmp_hier_private_bdata_t *tdata) {
tdata->num_active = num_active;
tdata->index = 0;
tdata->wait_val[0] = tdata->wait_val[1] = get_wait_val(num_active);
}
template <typename T>
void core_barrier_impl<T>::reset_shared(kmp_int32 num_active,
kmp_hier_shared_bdata_t<T> *bdata) {
bdata->val[0] = bdata->val[1] = 0LL;
bdata->status[0] = bdata->status[1] = 0LL;
}
template <typename T>
void core_barrier_impl<T>::barrier(kmp_int32 id,
kmp_hier_shared_bdata_t<T> *bdata,
kmp_hier_private_bdata_t *tdata) {
kmp_uint64 current_index = tdata->index;
kmp_uint64 next_index = 1 - current_index;
kmp_uint64 current_wait_value = tdata->wait_val[current_index];
kmp_uint64 next_wait_value =
(current_wait_value ? 0 : get_wait_val(tdata->num_active));
KD_TRACE(10, ("core_barrier_impl::barrier(): T#%d current_index:%llu "
"next_index:%llu curr_wait:%llu next_wait:%llu\n",
__kmp_get_gtid(), current_index, next_index, current_wait_value,
next_wait_value));
char v = (current_wait_value ? 0x1 : 0x0);
(RCAST(volatile char *, &(bdata->val[current_index])))[id] = v;
__kmp_wait<kmp_uint64>(&(bdata->val[current_index]), current_wait_value,
__kmp_eq<kmp_uint64> USE_ITT_BUILD_ARG(NULL));
tdata->wait_val[current_index] = next_wait_value;
tdata->index = next_index;
}
// Counter barrier implementation
// Can be used in a unit with arbitrary number of active threads
template <typename T> class counter_barrier_impl {
public:
static void reset_private(kmp_int32 num_active,
kmp_hier_private_bdata_t *tdata);
static void reset_shared(kmp_int32 num_active,
kmp_hier_shared_bdata_t<T> *bdata);
static void barrier(kmp_int32 id, kmp_hier_shared_bdata_t<T> *bdata,
kmp_hier_private_bdata_t *tdata);
};
template <typename T>
void counter_barrier_impl<T>::reset_private(kmp_int32 num_active,
kmp_hier_private_bdata_t *tdata) {
tdata->num_active = num_active;
tdata->index = 0;
tdata->wait_val[0] = tdata->wait_val[1] = (kmp_uint64)num_active;
}
template <typename T>
void counter_barrier_impl<T>::reset_shared(kmp_int32 num_active,
kmp_hier_shared_bdata_t<T> *bdata) {
bdata->val[0] = bdata->val[1] = 0LL;
bdata->status[0] = bdata->status[1] = 0LL;
}
template <typename T>
void counter_barrier_impl<T>::barrier(kmp_int32 id,
kmp_hier_shared_bdata_t<T> *bdata,
kmp_hier_private_bdata_t *tdata) {
volatile kmp_int64 *val;
kmp_uint64 current_index = tdata->index;
kmp_uint64 next_index = 1 - current_index;
kmp_uint64 current_wait_value = tdata->wait_val[current_index];
kmp_uint64 next_wait_value = current_wait_value + tdata->num_active;
KD_TRACE(10, ("counter_barrier_impl::barrier(): T#%d current_index:%llu "
"next_index:%llu curr_wait:%llu next_wait:%llu\n",
__kmp_get_gtid(), current_index, next_index, current_wait_value,
next_wait_value));
val = RCAST(volatile kmp_int64 *, &(bdata->val[current_index]));
KMP_TEST_THEN_INC64(val);
__kmp_wait<kmp_uint64>(&(bdata->val[current_index]), current_wait_value,
__kmp_ge<kmp_uint64> USE_ITT_BUILD_ARG(NULL));
tdata->wait_val[current_index] = next_wait_value;
tdata->index = next_index;
}
// Data associated with topology unit within a layer
// For example, one kmp_hier_top_unit_t corresponds to one L1 cache
template <typename T> struct kmp_hier_top_unit_t {
typedef typename traits_t<T>::signed_t ST;
typedef typename traits_t<T>::unsigned_t UT;
kmp_int32 active; // number of topology units that communicate with this unit
// chunk information (lower/upper bound, stride, etc.)
dispatch_private_info_template<T> hier_pr;
kmp_hier_top_unit_t<T> *hier_parent; // pointer to parent unit
kmp_hier_shared_bdata_t<T> hier_barrier; // shared barrier data for this unit
kmp_int32 get_hier_id() const { return hier_pr.hier_id; }
void reset_shared_barrier() {
KMP_DEBUG_ASSERT(active > 0);
if (active == 1)
return;
hier_barrier.zero();
if (active >= 2 && active <= 8) {
core_barrier_impl<T>::reset_shared(active, &hier_barrier);
} else {
counter_barrier_impl<T>::reset_shared(active, &hier_barrier);
}
}
void reset_private_barrier(kmp_hier_private_bdata_t *tdata) {
KMP_DEBUG_ASSERT(tdata);
KMP_DEBUG_ASSERT(active > 0);
if (active == 1)
return;
if (active >= 2 && active <= 8) {
core_barrier_impl<T>::reset_private(active, tdata);
} else {
counter_barrier_impl<T>::reset_private(active, tdata);
}
}
void barrier(kmp_int32 id, kmp_hier_private_bdata_t *tdata) {
KMP_DEBUG_ASSERT(tdata);
KMP_DEBUG_ASSERT(active > 0);
KMP_DEBUG_ASSERT(id >= 0 && id < active);
if (active == 1) {
tdata->index = 1 - tdata->index;
return;
}
if (active >= 2 && active <= 8) {
core_barrier_impl<T>::barrier(id, &hier_barrier, tdata);
} else {
counter_barrier_impl<T>::barrier(id, &hier_barrier, tdata);
}
}
kmp_int32 get_next_status(kmp_uint64 index) const {
return hier_barrier.get_next_status(index);
}
T get_next_lb(kmp_uint64 index) const {
return hier_barrier.get_next_lb(index);
}
T get_next_ub(kmp_uint64 index) const {
return hier_barrier.get_next_ub(index);
}
ST get_next_st(kmp_uint64 index) const {
return hier_barrier.get_next_st(index);
}
dispatch_shared_info_template<T> volatile *get_next_sh(kmp_uint64 index) {
return hier_barrier.get_next_sh(index);
}
kmp_int32 get_curr_status(kmp_uint64 index) const {
return hier_barrier.get_curr_status(index);
}
T get_curr_lb(kmp_uint64 index) const {
return hier_barrier.get_curr_lb(index);
}
T get_curr_ub(kmp_uint64 index) const {
return hier_barrier.get_curr_ub(index);
}
ST get_curr_st(kmp_uint64 index) const {
return hier_barrier.get_curr_st(index);
}
dispatch_shared_info_template<T> volatile *get_curr_sh(kmp_uint64 index) {
return hier_barrier.get_curr_sh(index);
}
void set_next_hand_thread(T lb, T ub, ST st, kmp_int32 status,
kmp_uint64 index) {
hier_barrier.set_next_hand_thread(lb, ub, st, status, index);
}
void set_next(T lb, T ub, ST st, kmp_int32 status, kmp_uint64 index) {
hier_barrier.set_next(lb, ub, st, status, index);
}
dispatch_private_info_template<T> *get_my_pr() { return &hier_pr; }
kmp_hier_top_unit_t<T> *get_parent() { return hier_parent; }
dispatch_private_info_template<T> *get_parent_pr() {
return &(hier_parent->hier_pr);
}
kmp_int32 is_active() const { return active; }
kmp_int32 get_num_active() const { return active; }
#ifdef KMP_DEBUG
void print() {
KD_TRACE(
10,
(" kmp_hier_top_unit_t: active:%d pr:%p lb:%d ub:%d st:%d tc:%d\n",
active, &hier_pr, hier_pr.u.p.lb, hier_pr.u.p.ub, hier_pr.u.p.st,
hier_pr.u.p.tc));
}
#endif
};
// Information regarding a single layer within the scheduling hierarchy
template <typename T> struct kmp_hier_layer_info_t {
int num_active; // number of threads active in this level
kmp_hier_layer_e type; // LAYER_L1, LAYER_L2, etc.
enum sched_type sched; // static, dynamic, guided, etc.
typename traits_t<T>::signed_t chunk; // chunk size associated with schedule
int length; // length of the kmp_hier_top_unit_t array
#ifdef KMP_DEBUG
// Print this layer's information
void print() {
const char *t = __kmp_get_hier_str(type);
KD_TRACE(
10,
(" kmp_hier_layer_info_t: num_active:%d type:%s sched:%d chunk:%d "
"length:%d\n",
num_active, t, sched, chunk, length));
}
#endif
};
/*
* Structure to implement entire hierarchy
*
* The hierarchy is kept as an array of arrays to represent the different
* layers. Layer 0 is the lowest layer to layer num_layers - 1 which is the
* highest layer.
* Example:
* [ 2 ] -> [ L3 | L3 ]
* [ 1 ] -> [ L2 | L2 | L2 | L2 ]
* [ 0 ] -> [ L1 | L1 | L1 | L1 | L1 | L1 | L1 | L1 ]
* There is also an array of layer_info_t which has information regarding
* each layer
*/
template <typename T> struct kmp_hier_t {
public:
typedef typename traits_t<T>::unsigned_t UT;
typedef typename traits_t<T>::signed_t ST;
private:
int next_recurse(ident_t *loc, int gtid, kmp_hier_top_unit_t<T> *current,
kmp_int32 *p_last, T *p_lb, T *p_ub, ST *p_st,
kmp_int32 previous_id, int hier_level) {
int status;
kmp_info_t *th = __kmp_threads[gtid];
auto parent = current->get_parent();
bool last_layer = (hier_level == get_num_layers() - 1);
KMP_DEBUG_ASSERT(th);
kmp_hier_private_bdata_t *tdata = &(th->th.th_hier_bar_data[hier_level]);
KMP_DEBUG_ASSERT(current);
KMP_DEBUG_ASSERT(hier_level >= 0);
KMP_DEBUG_ASSERT(hier_level < get_num_layers());
KMP_DEBUG_ASSERT(tdata);
KMP_DEBUG_ASSERT(parent || last_layer);
KD_TRACE(
1, ("kmp_hier_t.next_recurse(): T#%d (%d) called\n", gtid, hier_level));
T hier_id = (T)current->get_hier_id();
// Attempt to grab next iteration range for this level
if (previous_id == 0) {
KD_TRACE(1, ("kmp_hier_t.next_recurse(): T#%d (%d) is master of unit\n",
gtid, hier_level));
kmp_int32 contains_last;
T my_lb, my_ub;
ST my_st;
T nproc;
dispatch_shared_info_template<T> volatile *my_sh;
dispatch_private_info_template<T> *my_pr;
if (last_layer) {
// last layer below the very top uses the single shared buffer
// from the team struct.
KD_TRACE(10,
("kmp_hier_t.next_recurse(): T#%d (%d) using top level sh\n",
gtid, hier_level));
my_sh = reinterpret_cast<dispatch_shared_info_template<T> volatile *>(
th->th.th_dispatch->th_dispatch_sh_current);
nproc = (T)get_top_level_nproc();
} else {
// middle layers use the shared buffer inside the kmp_hier_top_unit_t
// structure
KD_TRACE(10, ("kmp_hier_t.next_recurse(): T#%d (%d) using hier sh\n",
gtid, hier_level));
my_sh =
parent->get_curr_sh(th->th.th_hier_bar_data[hier_level + 1].index);
nproc = (T)parent->get_num_active();
}
my_pr = current->get_my_pr();
KMP_DEBUG_ASSERT(my_sh);
KMP_DEBUG_ASSERT(my_pr);
enum sched_type schedule = get_sched(hier_level);
ST chunk = (ST)get_chunk(hier_level);
status = __kmp_dispatch_next_algorithm<T>(gtid, my_pr, my_sh,
&contains_last, &my_lb, &my_ub,
&my_st, nproc, hier_id);
KD_TRACE(
10,
("kmp_hier_t.next_recurse(): T#%d (%d) next_pr_sh() returned %d\n",
gtid, hier_level, status));
// When no iterations are found (status == 0) and this is not the last
// layer, attempt to go up the hierarchy for more iterations
if (status == 0 && !last_layer) {
status = next_recurse(loc, gtid, parent, &contains_last, &my_lb, &my_ub,
&my_st, hier_id, hier_level + 1);
KD_TRACE(
10,
("kmp_hier_t.next_recurse(): T#%d (%d) hier_next() returned %d\n",
gtid, hier_level, status));
if (status == 1) {
kmp_hier_private_bdata_t *upper_tdata =
&(th->th.th_hier_bar_data[hier_level + 1]);
my_sh = parent->get_curr_sh(upper_tdata->index);
KD_TRACE(10, ("kmp_hier_t.next_recurse(): T#%d (%d) about to init\n",
gtid, hier_level));
__kmp_dispatch_init_algorithm(loc, gtid, my_pr, schedule,
parent->get_curr_lb(upper_tdata->index),
parent->get_curr_ub(upper_tdata->index),
parent->get_curr_st(upper_tdata->index),
#if USE_ITT_BUILD
NULL,
#endif
chunk, nproc, hier_id);
status = __kmp_dispatch_next_algorithm<T>(
gtid, my_pr, my_sh, &contains_last, &my_lb, &my_ub, &my_st, nproc,
hier_id);
if (!status) {
KD_TRACE(10, ("kmp_hier_t.next_recurse(): T#%d (%d) status not 1 "
"setting to 2!\n",
gtid, hier_level));
status = 2;
}
}
}
current->set_next(my_lb, my_ub, my_st, status, tdata->index);
// Propagate whether a unit holds the actual global last iteration
// The contains_last attribute is sent downwards from the top to the
// bottom of the hierarchy via the contains_last flag inside the
// private dispatch buffers in the hierarchy's middle layers
if (contains_last) {
// If the next_algorithm() method returns 1 for p_last and it is the
// last layer or our parent contains the last serial chunk, then the
// chunk must contain the last serial iteration.
if (last_layer || parent->hier_pr.flags.contains_last) {
KD_TRACE(10, ("kmp_hier_t.next_recurse(): T#%d (%d) Setting this pr "
"to contain last.\n",
gtid, hier_level));
current->hier_pr.flags.contains_last = contains_last;
}
if (!current->hier_pr.flags.contains_last)
contains_last = FALSE;
}
if (p_last)
*p_last = contains_last;
} // if master thread of this unit
if (hier_level > 0 || !__kmp_dispatch_hand_threading) {
KD_TRACE(10,
("kmp_hier_t.next_recurse(): T#%d (%d) going into barrier.\n",
gtid, hier_level));
current->barrier(previous_id, tdata);
KD_TRACE(10,
("kmp_hier_t.next_recurse(): T#%d (%d) released and exit %d\n",
gtid, hier_level, current->get_curr_status(tdata->index)));
} else {
KMP_DEBUG_ASSERT(previous_id == 0);
return status;
}
return current->get_curr_status(tdata->index);
}
public:
int top_level_nproc;
int num_layers;
bool valid;
int type_size;
kmp_hier_layer_info_t<T> *info;
kmp_hier_top_unit_t<T> **layers;
// Deallocate all memory from this hierarchy
void deallocate() {
for (int i = 0; i < num_layers; ++i)
if (layers[i] != NULL) {
__kmp_free(layers[i]);
}
if (layers != NULL) {
__kmp_free(layers);
layers = NULL;
}
if (info != NULL) {
__kmp_free(info);
info = NULL;
}
num_layers = 0;
valid = false;
}
// Returns true if reallocation is needed else false
bool need_to_reallocate(int n, const kmp_hier_layer_e *new_layers,
const enum sched_type *new_scheds,
const ST *new_chunks) const {
if (!valid || layers == NULL || info == NULL ||
traits_t<T>::type_size != type_size || n != num_layers)
return true;
for (int i = 0; i < n; ++i) {
if (info[i].type != new_layers[i])
return true;
if (info[i].sched != new_scheds[i])
return true;
if (info[i].chunk != new_chunks[i])
return true;
}
return false;
}
// A single thread should call this function while the other threads wait
// create a new scheduling hierarchy consisting of new_layers, new_scheds
// and new_chunks. These should come pre-sorted according to
// kmp_hier_layer_e value. This function will try to avoid reallocation
// if it can
void allocate_hier(int n, const kmp_hier_layer_e *new_layers,
const enum sched_type *new_scheds, const ST *new_chunks) {
top_level_nproc = 0;
if (!need_to_reallocate(n, new_layers, new_scheds, new_chunks)) {
KD_TRACE(
10,
("kmp_hier_t<T>::allocate_hier: T#0 do not need to reallocate\n"));
for (int i = 0; i < n; ++i) {
info[i].num_active = 0;
for (int j = 0; j < get_length(i); ++j)
layers[i][j].active = 0;
}
return;
}
KD_TRACE(10, ("kmp_hier_t<T>::allocate_hier: T#0 full alloc\n"));
deallocate();
type_size = traits_t<T>::type_size;
num_layers = n;
info = (kmp_hier_layer_info_t<T> *)__kmp_allocate(
sizeof(kmp_hier_layer_info_t<T>) * n);
layers = (kmp_hier_top_unit_t<T> **)__kmp_allocate(
sizeof(kmp_hier_top_unit_t<T> *) * n);
for (int i = 0; i < n; ++i) {
int max = 0;
kmp_hier_layer_e layer = new_layers[i];
info[i].num_active = 0;
info[i].type = layer;
info[i].sched = new_scheds[i];
info[i].chunk = new_chunks[i];
max = __kmp_hier_max_units[layer + 1];
if (max == 0) {
valid = false;
KMP_WARNING(HierSchedInvalid, __kmp_get_hier_str(layer));
deallocate();
return;
}
info[i].length = max;
layers[i] = (kmp_hier_top_unit_t<T> *)__kmp_allocate(
sizeof(kmp_hier_top_unit_t<T>) * max);
for (int j = 0; j < max; ++j) {
layers[i][j].active = 0;
layers[i][j].hier_pr.flags.use_hier = TRUE;
}
}
valid = true;
}
// loc - source file location
// gtid - global thread identifier
// pr - this thread's private dispatch buffer (corresponding with gtid)
// p_last (return value) - pointer to flag indicating this set of iterations
// contains last
// iteration
// p_lb (return value) - lower bound for this chunk of iterations
// p_ub (return value) - upper bound for this chunk of iterations
// p_st (return value) - stride for this chunk of iterations
//
// Returns 1 if there are more iterations to perform, 0 otherwise
int next(ident_t *loc, int gtid, dispatch_private_info_template<T> *pr,
kmp_int32 *p_last, T *p_lb, T *p_ub, ST *p_st) {
int status;
kmp_int32 contains_last = 0;
kmp_info_t *th = __kmp_threads[gtid];
kmp_hier_private_bdata_t *tdata = &(th->th.th_hier_bar_data[0]);
auto parent = pr->get_parent();
KMP_DEBUG_ASSERT(parent);
KMP_DEBUG_ASSERT(th);
KMP_DEBUG_ASSERT(tdata);
KMP_DEBUG_ASSERT(parent);
T nproc = (T)parent->get_num_active();
T unit_id = (T)pr->get_hier_id();
KD_TRACE(
10,
("kmp_hier_t.next(): T#%d THREAD LEVEL nproc:%d unit_id:%d called\n",
gtid, nproc, unit_id));
// Handthreading implementation
// Each iteration is performed by all threads on last unit (typically
// cores/tiles)
// e.g., threads 0,1,2,3 all execute iteration 0
// threads 0,1,2,3 all execute iteration 1
// threads 4,5,6,7 all execute iteration 2
// threads 4,5,6,7 all execute iteration 3
// ... etc.
if (__kmp_dispatch_hand_threading) {
KD_TRACE(10,
("kmp_hier_t.next(): T#%d THREAD LEVEL using hand threading\n",
gtid));
if (unit_id == 0) {
// For hand threading, the sh buffer on the lowest level is only ever
// modified and read by the master thread on that level. Because of
// this, we can always use the first sh buffer.
auto sh = &(parent->hier_barrier.sh[0]);
KMP_DEBUG_ASSERT(sh);
status = __kmp_dispatch_next_algorithm<T>(
gtid, pr, sh, &contains_last, p_lb, p_ub, p_st, nproc, unit_id);
if (!status) {
bool done = false;
while (!done) {
done = true;
status = next_recurse(loc, gtid, parent, &contains_last, p_lb, p_ub,
p_st, unit_id, 0);
if (status == 1) {
__kmp_dispatch_init_algorithm(loc, gtid, pr, pr->schedule,
parent->get_next_lb(tdata->index),
parent->get_next_ub(tdata->index),
parent->get_next_st(tdata->index),
#if USE_ITT_BUILD
NULL,
#endif
pr->u.p.parm1, nproc, unit_id);
sh->u.s.iteration = 0;
status = __kmp_dispatch_next_algorithm<T>(
gtid, pr, sh, &contains_last, p_lb, p_ub, p_st, nproc,
unit_id);
if (!status) {
KD_TRACE(10,
("kmp_hier_t.next(): T#%d THREAD LEVEL status == 0 "
"after next_pr_sh()"
"trying again.\n",
gtid));
done = false;
}
} else if (status == 2) {
KD_TRACE(10, ("kmp_hier_t.next(): T#%d THREAD LEVEL status == 2 "
"trying again.\n",
gtid));
done = false;
}
}
}
parent->set_next_hand_thread(*p_lb, *p_ub, *p_st, status, tdata->index);
} // if master thread of lowest unit level
parent->barrier(pr->get_hier_id(), tdata);
if (unit_id != 0) {
*p_lb = parent->get_curr_lb(tdata->index);
*p_ub = parent->get_curr_ub(tdata->index);
*p_st = parent->get_curr_st(tdata->index);
status = parent->get_curr_status(tdata->index);
}
} else {
// Normal implementation
// Each thread grabs an iteration chunk and executes it (no cooperation)
auto sh = parent->get_curr_sh(tdata->index);
KMP_DEBUG_ASSERT(sh);
status = __kmp_dispatch_next_algorithm<T>(
gtid, pr, sh, &contains_last, p_lb, p_ub, p_st, nproc, unit_id);
KD_TRACE(10,
("kmp_hier_t.next(): T#%d THREAD LEVEL next_algorithm status:%d "
"contains_last:%d p_lb:%d p_ub:%d p_st:%d\n",
gtid, status, contains_last, *p_lb, *p_ub, *p_st));
if (!status) {
bool done = false;
while (!done) {
done = true;
status = next_recurse(loc, gtid, parent, &contains_last, p_lb, p_ub,
p_st, unit_id, 0);
if (status == 1) {
sh = parent->get_curr_sh(tdata->index);
__kmp_dispatch_init_algorithm(loc, gtid, pr, pr->schedule,
parent->get_curr_lb(tdata->index),
parent->get_curr_ub(tdata->index),
parent->get_curr_st(tdata->index),
#if USE_ITT_BUILD
NULL,
#endif
pr->u.p.parm1, nproc, unit_id);
status = __kmp_dispatch_next_algorithm<T>(
gtid, pr, sh, &contains_last, p_lb, p_ub, p_st, nproc, unit_id);
if (!status) {
KD_TRACE(10, ("kmp_hier_t.next(): T#%d THREAD LEVEL status == 0 "
"after next_pr_sh()"
"trying again.\n",
gtid));
done = false;
}
} else if (status == 2) {
KD_TRACE(10, ("kmp_hier_t.next(): T#%d THREAD LEVEL status == 2 "
"trying again.\n",
gtid));
done = false;
}
}
}
}
if (contains_last && !parent->hier_pr.flags.contains_last) {
KD_TRACE(10, ("kmp_hier_t.next(): T#%d THREAD LEVEL resetting "
"contains_last to FALSE\n",
gtid));
contains_last = FALSE;
}
if (p_last)
*p_last = contains_last;
KD_TRACE(10, ("kmp_hier_t.next(): T#%d THREAD LEVEL exit status %d\n", gtid,
status));
return status;
}
// These functions probe the layer info structure
// Returns the type of topology unit given level
kmp_hier_layer_e get_type(int level) const {
KMP_DEBUG_ASSERT(level >= 0);
KMP_DEBUG_ASSERT(level < num_layers);
return info[level].type;
}
// Returns the schedule type at given level
enum sched_type get_sched(int level) const {
KMP_DEBUG_ASSERT(level >= 0);
KMP_DEBUG_ASSERT(level < num_layers);
return info[level].sched;
}
// Returns the chunk size at given level
ST get_chunk(int level) const {
KMP_DEBUG_ASSERT(level >= 0);
KMP_DEBUG_ASSERT(level < num_layers);
return info[level].chunk;
}
// Returns the number of active threads at given level
int get_num_active(int level) const {
KMP_DEBUG_ASSERT(level >= 0);
KMP_DEBUG_ASSERT(level < num_layers);
return info[level].num_active;
}
// Returns the length of topology unit array at given level
int get_length(int level) const {
KMP_DEBUG_ASSERT(level >= 0);
KMP_DEBUG_ASSERT(level < num_layers);
return info[level].length;
}
// Returns the topology unit given the level and index
kmp_hier_top_unit_t<T> *get_unit(int level, int index) {
KMP_DEBUG_ASSERT(level >= 0);
KMP_DEBUG_ASSERT(level < num_layers);
KMP_DEBUG_ASSERT(index >= 0);
KMP_DEBUG_ASSERT(index < get_length(level));
return &(layers[level][index]);
}
// Returns the number of layers in the hierarchy
int get_num_layers() const { return num_layers; }
// Returns the number of threads in the top layer
// This is necessary because we don't store a topology unit as
// the very top level and the scheduling algorithms need this information
int get_top_level_nproc() const { return top_level_nproc; }
// Return whether this hierarchy is valid or not
bool is_valid() const { return valid; }
#ifdef KMP_DEBUG
// Print the hierarchy
void print() {
KD_TRACE(10, ("kmp_hier_t:\n"));
for (int i = num_layers - 1; i >= 0; --i) {
KD_TRACE(10, ("Info[%d] = ", i));
info[i].print();
}
for (int i = num_layers - 1; i >= 0; --i) {
KD_TRACE(10, ("Layer[%d] =\n", i));
for (int j = 0; j < info[i].length; ++j) {
layers[i][j].print();
}
}
}
#endif
};
template <typename T>
void __kmp_dispatch_init_hierarchy(ident_t *loc, int n,
kmp_hier_layer_e *new_layers,
enum sched_type *new_scheds,
typename traits_t<T>::signed_t *new_chunks,
T lb, T ub,
typename traits_t<T>::signed_t st) {
int tid, gtid, num_hw_threads, num_threads_per_layer1, active;
int my_buffer_index;
kmp_info_t *th;
kmp_team_t *team;
dispatch_private_info_template<T> *pr;
dispatch_shared_info_template<T> volatile *sh;
gtid = __kmp_entry_gtid();
tid = __kmp_tid_from_gtid(gtid);
#ifdef KMP_DEBUG
KD_TRACE(10, ("__kmp_dispatch_init_hierarchy: T#%d called: %d layer(s)\n",
gtid, n));
for (int i = 0; i < n; ++i) {
const char *layer = __kmp_get_hier_str(new_layers[i]);
KD_TRACE(10, ("__kmp_dispatch_init_hierarchy: T#%d: new_layers[%d] = %s, "
"new_scheds[%d] = %d, new_chunks[%d] = %u\n",
gtid, i, layer, i, (int)new_scheds[i], i, new_chunks[i]));
}
#endif // KMP_DEBUG
KMP_DEBUG_ASSERT(n > 0);
KMP_DEBUG_ASSERT(new_layers);
KMP_DEBUG_ASSERT(new_scheds);
KMP_DEBUG_ASSERT(new_chunks);
if (!TCR_4(__kmp_init_parallel))
__kmp_parallel_initialize();
__kmp_resume_if_soft_paused();
th = __kmp_threads[gtid];
team = th->th.th_team;
active = !team->t.t_serialized;
th->th.th_ident = loc;
num_hw_threads = __kmp_hier_max_units[kmp_hier_layer_e::LAYER_THREAD + 1];
KMP_DEBUG_ASSERT(th->th.th_dispatch ==
&th->th.th_team->t.t_dispatch[th->th.th_info.ds.ds_tid]);
my_buffer_index = th->th.th_dispatch->th_disp_index;
pr = reinterpret_cast<dispatch_private_info_template<T> *>(
&th->th.th_dispatch
->th_disp_buffer[my_buffer_index % __kmp_dispatch_num_buffers]);
sh = reinterpret_cast<dispatch_shared_info_template<T> volatile *>(
&team->t.t_disp_buffer[my_buffer_index % __kmp_dispatch_num_buffers]);
if (!active) {
KD_TRACE(10, ("__kmp_dispatch_init_hierarchy: T#%d not active parallel. "
"Using normal dispatch functions.\n",
gtid));
KMP_DEBUG_ASSERT(pr);
pr->flags.use_hier = FALSE;
pr->flags.contains_last = FALSE;
return;
}
KMP_DEBUG_ASSERT(pr);
KMP_DEBUG_ASSERT(sh);
pr->flags.use_hier = TRUE;
pr->u.p.tc = 0;
// Have master allocate the hierarchy
if (__kmp_tid_from_gtid(gtid) == 0) {
KD_TRACE(10, ("__kmp_dispatch_init_hierarchy: T#%d pr:%p sh:%p allocating "
"hierarchy\n",
gtid, pr, sh));
if (sh->hier == NULL) {
sh->hier = (kmp_hier_t<T> *)__kmp_allocate(sizeof(kmp_hier_t<T>));
}
sh->hier->allocate_hier(n, new_layers, new_scheds, new_chunks);
sh->u.s.iteration = 0;
}
__kmp_barrier(bs_plain_barrier, gtid, FALSE, 0, NULL, NULL);
// Check to make sure the hierarchy is valid
kmp_hier_t<T> *hier = sh->hier;
if (!sh->hier->is_valid()) {
pr->flags.use_hier = FALSE;
return;
}
// Have threads allocate their thread-private barrier data if it hasn't
// already been allocated
if (th->th.th_hier_bar_data == NULL) {
th->th.th_hier_bar_data = (kmp_hier_private_bdata_t *)__kmp_allocate(
sizeof(kmp_hier_private_bdata_t) * kmp_hier_layer_e::LAYER_LAST);
}
// Have threads "register" themselves by modifying the active count for each
// level they are involved in. The active count will act as nthreads for that
// level regarding the scheduling algorithms
for (int i = 0; i < n; ++i) {
int index = __kmp_dispatch_get_index(tid, hier->get_type(i));
kmp_hier_top_unit_t<T> *my_unit = hier->get_unit(i, index);
// Setup the thread's private dispatch buffer's hierarchy pointers
if (i == 0)
pr->hier_parent = my_unit;
// If this unit is already active, then increment active count and wait
if (my_unit->is_active()) {
KD_TRACE(10, ("__kmp_dispatch_init_hierarchy: T#%d my_unit (%p) "
"is already active (%d)\n",
gtid, my_unit, my_unit->active));
KMP_TEST_THEN_INC32(&(my_unit->active));
break;
}
// Flag that this unit is active
if (KMP_COMPARE_AND_STORE_ACQ32(&(my_unit->active), 0, 1)) {
// Do not setup parent pointer for top level unit since it has no parent
if (i < n - 1) {
// Setup middle layer pointers to parents
my_unit->get_my_pr()->hier_id =
index % __kmp_dispatch_get_t1_per_t2(hier->get_type(i),
hier->get_type(i + 1));
int parent_index = __kmp_dispatch_get_index(tid, hier->get_type(i + 1));
my_unit->hier_parent = hier->get_unit(i + 1, parent_index);
} else {
// Setup top layer information (no parent pointers are set)
my_unit->get_my_pr()->hier_id =
index % __kmp_dispatch_get_t1_per_t2(hier->get_type(i),
kmp_hier_layer_e::LAYER_LOOP);
KMP_TEST_THEN_INC32(&(hier->top_level_nproc));
my_unit->hier_parent = nullptr;
}
// Set trip count to 0 so that next() operation will initially climb up
// the hierarchy to get more iterations (early exit in next() for tc == 0)
my_unit->get_my_pr()->u.p.tc = 0;
// Increment this layer's number of active units
KMP_TEST_THEN_INC32(&(hier->info[i].num_active));
KD_TRACE(10, ("__kmp_dispatch_init_hierarchy: T#%d my_unit (%p) "
"incrementing num_active\n",
gtid, my_unit));
} else {
KMP_TEST_THEN_INC32(&(my_unit->active));
break;
}
}
// Set this thread's id
num_threads_per_layer1 = __kmp_dispatch_get_t1_per_t2(
kmp_hier_layer_e::LAYER_THREAD, hier->get_type(0));
pr->hier_id = tid % num_threads_per_layer1;
// For oversubscribed threads, increment their index within the lowest unit
// This is done to prevent having two or more threads with id 0, id 1, etc.
if (tid >= num_hw_threads)
pr->hier_id += ((tid / num_hw_threads) * num_threads_per_layer1);
KD_TRACE(
10, ("__kmp_dispatch_init_hierarchy: T#%d setting lowest hier_id to %d\n",
gtid, pr->hier_id));
pr->flags.contains_last = FALSE;
__kmp_barrier(bs_plain_barrier, gtid, FALSE, 0, NULL, NULL);
// Now that the number of active threads at each level is determined,
// the barrier data for each unit can be initialized and the last layer's
// loop information can be initialized.
int prev_id = pr->get_hier_id();
for (int i = 0; i < n; ++i) {
if (prev_id != 0)
break;
int index = __kmp_dispatch_get_index(tid, hier->get_type(i));
kmp_hier_top_unit_t<T> *my_unit = hier->get_unit(i, index);
// Only master threads of this unit within the hierarchy do initialization
KD_TRACE(10, ("__kmp_dispatch_init_hierarchy: T#%d (%d) prev_id is 0\n",
gtid, i));
my_unit->reset_shared_barrier();
my_unit->hier_pr.flags.contains_last = FALSE;
// Last layer, initialize the private buffers with entire loop information
// Now the next next_algorithm() call will get the first chunk of
// iterations properly
if (i == n - 1) {
__kmp_dispatch_init_algorithm<T>(
loc, gtid, my_unit->get_my_pr(), hier->get_sched(i), lb, ub, st,
#if USE_ITT_BUILD
NULL,
#endif
hier->get_chunk(i), hier->get_num_active(i), my_unit->get_hier_id());
}
prev_id = my_unit->get_hier_id();
}
// Initialize each layer of the thread's private barrier data
kmp_hier_top_unit_t<T> *unit = pr->hier_parent;
for (int i = 0; i < n && unit; ++i, unit = unit->get_parent()) {
kmp_hier_private_bdata_t *tdata = &(th->th.th_hier_bar_data[i]);
unit->reset_private_barrier(tdata);
}
__kmp_barrier(bs_plain_barrier, gtid, FALSE, 0, NULL, NULL);
#ifdef KMP_DEBUG
if (__kmp_tid_from_gtid(gtid) == 0) {
for (int i = 0; i < n; ++i) {
KD_TRACE(10,
("__kmp_dispatch_init_hierarchy: T#%d active count[%d] = %d\n",
gtid, i, hier->get_num_active(i)));
}
hier->print();
}
__kmp_barrier(bs_plain_barrier, gtid, FALSE, 0, NULL, NULL);
#endif // KMP_DEBUG
}
#endif
sched_type
sched_type
Definition: kmp.h:336
ident
Definition: kmp.h:222