Differential D7385 Diff 23593 source/blender/blenlib/intern/task_iterator.c

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source/blender/blenlib/intern/task_iterator.c

This file was moved from source/blender/blenlib/intern/task.c.

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#include "BLI_listbase.h"		#include "BLI_listbase.h"
#include "BLI_math.h"		#include "BLI_math.h"
#include "BLI_mempool.h"		#include "BLI_mempool.h"
#include "BLI_task.h"		#include "BLI_task.h"
#include "BLI_threads.h"		#include "BLI_threads.h"

#include "atomic_ops.h"		#include "atomic_ops.h"

/* Define this to enable some detailed statistic print. */
#undef DEBUG_STATS

/* Types */

/* Number of per-thread pre-allocated tasks.
*
* For more details see description of TaskMemPool.
*/
#define MEMPOOL_SIZE 256

/* Number of tasks which are pushed directly to local thread queue.
*
* This allows thread to fetch next task without locking the whole queue.
*/
#define LOCAL_QUEUE_SIZE 1

/* Number of tasks which are allowed to be scheduled in a delayed manner.
*
* This allows to use less locks per graph node children schedule. More details
* could be found at TaskThreadLocalStorage::do_delayed_push.
*/
#define DELAYED_QUEUE_SIZE 4096

#ifndef NDEBUG
# define ASSERT_THREAD_ID(scheduler, thread_id) \
do { \
if (!BLI_thread_is_main()) { \
TaskThread *thread = pthread_getspecific(scheduler->tls_id_key); \
if (thread == NULL) { \
BLI_assert(thread_id == 0); \
} \
else { \
BLI_assert(thread_id == thread->id); \
} \
} \
else { \
BLI_assert(thread_id == 0); \
} \
} while (false)
#else
# define ASSERT_THREAD_ID(scheduler, thread_id)
#endif

typedef struct Task {
struct Task next, prev;

TaskRunFunction run;
void *taskdata;
bool free_taskdata;
TaskFreeFunction freedata;
TaskPool *pool;
} Task;

/* This is a per-thread storage of pre-allocated tasks.
*
* The idea behind this is simple: reduce amount of malloc() calls when pushing
* new task to the pool. This is done by keeping memory from the tasks which
* were finished already, so instead of freeing that memory we put it to the
* pool for the later re-use.
*
* The tricky part here is to avoid any inter-thread synchronization, hence no
* lock must exist around this pool. The pool will become an owner of the pointer
* from freed task, and only corresponding thread will be able to use this pool
* (no memory stealing and such).
*
* This leads to the following use of the pool:
*
* - task_push() should provide proper thread ID from which the task is being
* pushed from.
*
* - Task allocation function which check corresponding memory pool and if there
* is any memory in there it'll mark memory as re-used, remove it from the pool
* and use that memory for the new task.
*
* At this moment task queue owns the memory.
*
* - When task is done and task_free() is called the memory will be put to the
* pool which corresponds to a thread which handled the task.
*/
typedef struct TaskMemPool {
/* Number of pre-allocated tasks in the pool. */
int num_tasks;
/* Pre-allocated task memory pointers. */
Task *tasks[MEMPOOL_SIZE];
} TaskMemPool;

#ifdef DEBUG_STATS
typedef struct TaskMemPoolStats {
/* Number of allocations. */
int num_alloc;
/* Number of avoided allocations (pointer was re-used from the pool). */
int num_reuse;
/* Number of discarded memory due to pool saturation, */
int num_discard;
} TaskMemPoolStats;
#endif

typedef struct TaskThreadLocalStorage {
/* Memory pool for faster task allocation.
* The idea is to re-use memory of finished/discarded tasks by this thread.
*/
TaskMemPool task_mempool;

/* Local queue keeps thread alive by keeping small amount of tasks ready
* to be picked up without causing global thread locks for synchronization.
*/
int num_local_queue;
Task *local_queue[LOCAL_QUEUE_SIZE];

/* Thread can be marked for delayed tasks push. This is helpful when it's
* know that lots of subsequent task pushed will happen from the same thread
* without "interrupting" for task execution.
*
* We try to accumulate as much tasks as possible in a local queue without
* any locks first, and then we push all of them into a scheduler's queue
* from within a single mutex lock.
*/
bool do_delayed_push;
int num_delayed_queue;
Task *delayed_queue[DELAYED_QUEUE_SIZE];
} TaskThreadLocalStorage;

struct TaskPool {
TaskScheduler *scheduler;

volatile size_t num;
ThreadMutex num_mutex;
ThreadCondition num_cond;

void *userdata;
ThreadMutex user_mutex;

volatile bool do_cancel;
volatile bool do_work;

volatile bool is_suspended;
bool start_suspended;
ListBase suspended_queue;
size_t num_suspended;

/* If set, this pool may never be work_and_wait'ed, which means TaskScheduler
* has to use its special background fallback thread in case we are in
* single-threaded situation.
*/
bool run_in_background;

/* This is a task scheduler's ID of a thread at which pool was constructed.
* It will be used to access task TLS.
*/
int thread_id;

/* For the pools which are created from non-main thread which is not a
* scheduler worker thread we can't re-use any of scheduler's threads TLS
* and have to use our own one.
*/
bool use_local_tls;
TaskThreadLocalStorage local_tls;
#ifndef NDEBUG
pthread_t creator_thread_id;
#endif

#ifdef DEBUG_STATS
TaskMemPoolStats *mempool_stats;
#endif
};

struct TaskScheduler {
pthread_t *threads;
struct TaskThread *task_threads;
int num_threads;
bool background_thread_only;

ListBase queue;
ThreadMutex queue_mutex;
ThreadCondition queue_cond;

ThreadMutex startup_mutex;
ThreadCondition startup_cond;
volatile int num_thread_started;

volatile bool do_exit;

/* NOTE: In pthread's TLS we store the whole TaskThread structure. */
pthread_key_t tls_id_key;
};

typedef struct TaskThread {
TaskScheduler *scheduler;
int id;
TaskThreadLocalStorage tls;
} TaskThread;

/* Helper */
BLI_INLINE void task_data_free(Task *task, const int thread_id)
{
if (task->free_taskdata) {
if (task->freedata) {
task->freedata(task->pool, task->taskdata, thread_id);
}
else {
MEM_freeN(task->taskdata);
}
}
}

BLI_INLINE void initialize_task_tls(TaskThreadLocalStorage *tls)
{
memset(tls, 0, sizeof(TaskThreadLocalStorage));
}

BLI_INLINE TaskThreadLocalStorage get_task_tls(TaskPool pool, const int thread_id)
{
TaskScheduler *scheduler = pool->scheduler;
BLI_assert(thread_id >= 0);
BLI_assert(thread_id <= scheduler->num_threads);
if (pool->use_local_tls && thread_id == 0) {
BLI_assert(pool->thread_id == 0);
BLI_assert(!BLI_thread_is_main());
BLI_assert(pthread_equal(pthread_self(), pool->creator_thread_id));
return &pool->local_tls;
}
if (thread_id == 0) {
BLI_assert(BLI_thread_is_main());
return &scheduler->task_threads[pool->thread_id].tls;
}
return &scheduler->task_threads[thread_id].tls;
}

BLI_INLINE void free_task_tls(TaskThreadLocalStorage *tls)
{
TaskMemPool *task_mempool = &tls->task_mempool;
for (int i = 0; i < task_mempool->num_tasks; i++) {
MEM_freeN(task_mempool->tasks[i]);
}
}

static Task task_alloc(TaskPool pool, const int thread_id)
{
BLI_assert(thread_id <= pool->scheduler->num_threads);
if (thread_id != -1) {
BLI_assert(thread_id >= 0);
BLI_assert(thread_id <= pool->scheduler->num_threads);
TaskThreadLocalStorage *tls = get_task_tls(pool, thread_id);
TaskMemPool *task_mempool = &tls->task_mempool;
/* Try to re-use task memory from a thread local storage. */
if (task_mempool->num_tasks > 0) {
--task_mempool->num_tasks;
/* Success! We've just avoided task allocation. */
#ifdef DEBUG_STATS
pool->mempool_stats[thread_id].num_reuse++;
#endif
return task_mempool->tasks[task_mempool->num_tasks];
}
/* We are doomed to allocate new task data. */
#ifdef DEBUG_STATS
pool->mempool_stats[thread_id].num_alloc++;
#endif
}
return MEM_mallocN(sizeof(Task), "New task");
}

static void task_free(TaskPool pool, Task task, const int thread_id)
{
task_data_free(task, thread_id);
BLI_assert(thread_id >= 0);
BLI_assert(thread_id <= pool->scheduler->num_threads);
if (thread_id == 0) {
BLI_assert(pool->use_local_tls \|\| BLI_thread_is_main());
}
TaskThreadLocalStorage *tls = get_task_tls(pool, thread_id);
TaskMemPool *task_mempool = &tls->task_mempool;
if (task_mempool->num_tasks < MEMPOOL_SIZE - 1) {
/* Successfully allowed the task to be re-used later. */
task_mempool->tasks[task_mempool->num_tasks] = task;
++task_mempool->num_tasks;
}
else {
/* Local storage saturated, no other way than just discard
* the memory.
*
* TODO(sergey): We can perhaps store such pointer in a global
* scheduler pool, maybe it'll be faster than discarding and
* allocating again.
*/
MEM_freeN(task);
#ifdef DEBUG_STATS
pool->mempool_stats[thread_id].num_discard++;
#endif
}
}

/* Task Scheduler */

static void task_pool_num_decrease(TaskPool *pool, size_t done)
{
BLI_mutex_lock(&pool->num_mutex);

BLI_assert(pool->num >= done);

pool->num -= done;

if (pool->num == 0) {
BLI_condition_notify_all(&pool->num_cond);
}

BLI_mutex_unlock(&pool->num_mutex);
}

static void task_pool_num_increase(TaskPool *pool, size_t new)
{
BLI_mutex_lock(&pool->num_mutex);

pool->num += new;
BLI_condition_notify_all(&pool->num_cond);

BLI_mutex_unlock(&pool->num_mutex);
}

static bool task_scheduler_thread_wait_pop(TaskScheduler scheduler, Task *task)
{
bool found_task = false;
BLI_mutex_lock(&scheduler->queue_mutex);

while (!scheduler->queue.first && !scheduler->do_exit) {
BLI_condition_wait(&scheduler->queue_cond, &scheduler->queue_mutex);
}

do {
Task *current_task;

/* Assuming we can only have a void queue in 'exit' case here seems logical
* (we should only be here after our worker thread has been woken up from a
* condition_wait(), which only happens after a new task was added to the queue),
* but it is wrong.
* Waiting on condition may wake up the thread even if condition is not signaled
* (spurious wake-ups), and some race condition may also empty the queue after
* condition has been signaled, but before awoken thread reaches this point...
* See http://stackoverflow.com/questions/8594591
*
* So we only abort here if do_exit is set.
*/
if (scheduler->do_exit) {
BLI_mutex_unlock(&scheduler->queue_mutex);
return false;
}

for (current_task = scheduler->queue.first; current_task != NULL;
current_task = current_task->next) {
TaskPool *pool = current_task->pool;

if (scheduler->background_thread_only && !pool->run_in_background) {
continue;
}

*task = current_task;
found_task = true;
BLI_remlink(&scheduler->queue, *task);
break;
}
if (!found_task) {
BLI_condition_wait(&scheduler->queue_cond, &scheduler->queue_mutex);
}
} while (!found_task);

BLI_mutex_unlock(&scheduler->queue_mutex);

return true;
}

BLI_INLINE void handle_local_queue(TaskThreadLocalStorage *tls, const int thread_id)
{
BLI_assert(!tls->do_delayed_push);
while (tls->num_local_queue > 0) {
/* We pop task from queue before handling it so handler of the task can
* push next job to the local queue.
*/
tls->num_local_queue--;
Task *local_task = tls->local_queue[tls->num_local_queue];
/* TODO(sergey): Double-check work_and_wait() doesn't handle other's
* pool tasks.
*/
TaskPool *local_pool = local_task->pool;
local_task->run(local_pool, local_task->taskdata, thread_id);
task_free(local_pool, local_task, thread_id);
}
BLI_assert(!tls->do_delayed_push);
}

static void task_scheduler_thread_run(void thread_p)
{
TaskThread thread = (TaskThread )thread_p;
TaskThreadLocalStorage *tls = &thread->tls;
TaskScheduler *scheduler = thread->scheduler;
int thread_id = thread->id;
Task *task;

pthread_setspecific(scheduler->tls_id_key, thread);

/* signal the main thread when all threads have started */
BLI_mutex_lock(&scheduler->startup_mutex);
scheduler->num_thread_started++;
if (scheduler->num_thread_started == scheduler->num_threads) {
BLI_condition_notify_one(&scheduler->startup_cond);
}
BLI_mutex_unlock(&scheduler->startup_mutex);

/* keep popping off tasks */
while (task_scheduler_thread_wait_pop(scheduler, &task)) {
TaskPool *pool = task->pool;

/* run task */
BLI_assert(!tls->do_delayed_push);
task->run(pool, task->taskdata, thread_id);
BLI_assert(!tls->do_delayed_push);

/* delete task */
task_free(pool, task, thread_id);

/* Handle all tasks from local queue. */
handle_local_queue(tls, thread_id);

/* notify pool task was done */
task_pool_num_decrease(pool, 1);
}

return NULL;
}

TaskScheduler *BLI_task_scheduler_create(int num_threads)
{
TaskScheduler *scheduler = MEM_callocN(sizeof(TaskScheduler), "TaskScheduler");

/* multiple places can use this task scheduler, sharing the same
* threads, so we keep track of the number of users. */
scheduler->do_exit = false;

BLI_listbase_clear(&scheduler->queue);
BLI_mutex_init(&scheduler->queue_mutex);
BLI_condition_init(&scheduler->queue_cond);

BLI_mutex_init(&scheduler->startup_mutex);
BLI_condition_init(&scheduler->startup_cond);
scheduler->num_thread_started = 0;

if (num_threads == 0) {
/* automatic number of threads will be main thread + num cores */
num_threads = BLI_system_thread_count();
}

/* main thread will also work, so we count it too */
num_threads -= 1;

/* Add background-only thread if needed. */
if (num_threads == 0) {
scheduler->background_thread_only = true;
num_threads = 1;
}

scheduler->task_threads = MEM_mallocN(sizeof(TaskThread) * (num_threads + 1),
"TaskScheduler task threads");

/* Initialize TLS for main thread. */
initialize_task_tls(&scheduler->task_threads[0].tls);

pthread_key_create(&scheduler->tls_id_key, NULL);

/* launch threads that will be waiting for work */
if (num_threads > 0) {
int i;

scheduler->num_threads = num_threads;
scheduler->threads = MEM_callocN(sizeof(pthread_t) * num_threads, "TaskScheduler threads");

for (i = 0; i < num_threads; i++) {
TaskThread *thread = &scheduler->task_threads[i + 1];
thread->scheduler = scheduler;
thread->id = i + 1;
initialize_task_tls(&thread->tls);

if (pthread_create(&scheduler->threads[i], NULL, task_scheduler_thread_run, thread) != 0) {
fprintf(stderr, "TaskScheduler failed to launch thread %d/%d\n", i, num_threads);
}
}
}

/* Wait for all worker threads to start before returning to caller to prevent the case where
* threads are still starting and pthread_join is called, which causes a deadlock on pthreads4w.
*/
BLI_mutex_lock(&scheduler->startup_mutex);
/* NOTE: Use loop here to avoid false-positive everything-is-ready caused by spontaneous thread
* wake up. */
while (scheduler->num_thread_started != num_threads) {
BLI_condition_wait(&scheduler->startup_cond, &scheduler->startup_mutex);
}
BLI_mutex_unlock(&scheduler->startup_mutex);

return scheduler;
}

void BLI_task_scheduler_free(TaskScheduler *scheduler)
{
Task *task;

/* stop all waiting threads */
BLI_mutex_lock(&scheduler->queue_mutex);
scheduler->do_exit = true;
BLI_condition_notify_all(&scheduler->queue_cond);
BLI_mutex_unlock(&scheduler->queue_mutex);

pthread_key_delete(scheduler->tls_id_key);

/* delete threads */
if (scheduler->threads) {
int i;

for (i = 0; i < scheduler->num_threads; i++) {
if (pthread_join(scheduler->threads[i], NULL) != 0) {
fprintf(stderr, "TaskScheduler failed to join thread %d/%d\n", i, scheduler->num_threads);
}
}

MEM_freeN(scheduler->threads);
}

/* Delete task thread data */
if (scheduler->task_threads) {
for (int i = 0; i < scheduler->num_threads + 1; i++) {
TaskThreadLocalStorage *tls = &scheduler->task_threads[i].tls;
free_task_tls(tls);
}

MEM_freeN(scheduler->task_threads);
}

/* delete leftover tasks */
for (task = scheduler->queue.first; task; task = task->next) {
task_data_free(task, 0);
}
BLI_freelistN(&scheduler->queue);

/* delete mutex/condition */
BLI_mutex_end(&scheduler->queue_mutex);
BLI_condition_end(&scheduler->queue_cond);
BLI_mutex_end(&scheduler->startup_mutex);
BLI_condition_end(&scheduler->startup_cond);

MEM_freeN(scheduler);
}

int BLI_task_scheduler_num_threads(TaskScheduler *scheduler)
{
return scheduler->num_threads + 1;
}

static void task_scheduler_push(TaskScheduler scheduler, Task task, TaskPriority priority)
{
task_pool_num_increase(task->pool, 1);

/* add task to queue */
BLI_mutex_lock(&scheduler->queue_mutex);

if (priority == TASK_PRIORITY_HIGH) {
BLI_addhead(&scheduler->queue, task);
}
else {
BLI_addtail(&scheduler->queue, task);
}

BLI_condition_notify_one(&scheduler->queue_cond);
BLI_mutex_unlock(&scheduler->queue_mutex);
}

static void task_scheduler_push_all(TaskScheduler *scheduler,
TaskPool *pool,
Task **tasks,
int num_tasks)
{
if (num_tasks == 0) {
return;
}

task_pool_num_increase(pool, num_tasks);

BLI_mutex_lock(&scheduler->queue_mutex);

for (int i = 0; i < num_tasks; i++) {
BLI_addhead(&scheduler->queue, tasks[i]);
}

BLI_condition_notify_all(&scheduler->queue_cond);
BLI_mutex_unlock(&scheduler->queue_mutex);
}

static void task_scheduler_clear(TaskScheduler scheduler, TaskPool pool)
{
Task task, nexttask;
size_t done = 0;

BLI_mutex_lock(&scheduler->queue_mutex);

/* free all tasks from this pool from the queue */
for (task = scheduler->queue.first; task; task = nexttask) {
nexttask = task->next;

if (task->pool == pool) {
task_data_free(task, pool->thread_id);
BLI_freelinkN(&scheduler->queue, task);

done++;
}
}

BLI_mutex_unlock(&scheduler->queue_mutex);

/* notify done */
task_pool_num_decrease(pool, done);
}

/* Task Pool */

static TaskPool task_pool_create_ex(TaskScheduler scheduler,
void *userdata,
const bool is_background,
const bool is_suspended)
{
TaskPool *pool = MEM_mallocN(sizeof(TaskPool), "TaskPool");

#ifndef NDEBUG
/* Assert we do not try to create a background pool from some parent task -
* those only work OK from main thread. */
if (is_background) {
const pthread_t thread_id = pthread_self();
int i = scheduler->num_threads;

while (i--) {
BLI_assert(!pthread_equal(scheduler->threads[i], thread_id));
}
}
#endif

pool->scheduler = scheduler;
pool->num = 0;
pool->do_cancel = false;
pool->do_work = false;
pool->is_suspended = is_suspended;
pool->start_suspended = is_suspended;
pool->num_suspended = 0;
pool->suspended_queue.first = pool->suspended_queue.last = NULL;
pool->run_in_background = is_background;
pool->use_local_tls = false;

BLI_mutex_init(&pool->num_mutex);
BLI_condition_init(&pool->num_cond);

pool->userdata = userdata;
BLI_mutex_init(&pool->user_mutex);

if (BLI_thread_is_main()) {
pool->thread_id = 0;
}
else {
TaskThread *thread = pthread_getspecific(scheduler->tls_id_key);
if (thread == NULL) {
/* NOTE: Task pool is created from non-main thread which is not
* managed by the task scheduler. We identify ourselves as thread ID
* 0 but we do not use scheduler's TLS storage and use our own
* instead to avoid any possible threading conflicts.
*/
pool->thread_id = 0;
pool->use_local_tls = true;
#ifndef NDEBUG
pool->creator_thread_id = pthread_self();
#endif
initialize_task_tls(&pool->local_tls);
}
else {
pool->thread_id = thread->id;
}
}

#ifdef DEBUG_STATS
pool->mempool_stats = MEM_callocN(sizeof(pool->mempool_stats) (scheduler->num_threads + 1),
"per-taskpool mempool stats");
#endif

/* Ensure malloc will go fine from threads,
*
* This is needed because we could be in main thread here
* and malloc could be non-thread safe at this point because
* no other jobs are running.
*/
BLI_threaded_malloc_begin();

return pool;
}

/**
* Create a normal task pool. Tasks will be executed as soon as they are added.
*/
TaskPool BLI_task_pool_create(TaskScheduler scheduler, void *userdata)
{
return task_pool_create_ex(scheduler, userdata, false, false);
}

/**
* Create a background task pool.
* In multi-threaded context, there is no differences with #BLI_task_pool_create(),
* but in single-threaded case it is ensured to have at least one worker thread to run on
* (i.e. you don't have to call #BLI_task_pool_work_and_wait
* on it to be sure it will be processed).
*
* \note Background pools are non-recursive
* (that is, you should not create other background pools in tasks assigned to a background pool,
* they could end never being executed, since the 'fallback' background thread is already
* busy with parent task in single-threaded context).
*/
TaskPool BLI_task_pool_create_background(TaskScheduler scheduler, void *userdata)
{
return task_pool_create_ex(scheduler, userdata, true, false);
}

/**
* Similar to BLI_task_pool_create() but does not schedule any tasks for execution
* for until BLI_task_pool_work_and_wait() is called. This helps reducing threading
* overhead when pushing huge amount of small initial tasks from the main thread.
*/
TaskPool BLI_task_pool_create_suspended(TaskScheduler scheduler, void *userdata)
{
return task_pool_create_ex(scheduler, userdata, false, true);
}

void BLI_task_pool_free(TaskPool *pool)
{
BLI_task_pool_cancel(pool);

BLI_mutex_end(&pool->num_mutex);
BLI_condition_end(&pool->num_cond);

BLI_mutex_end(&pool->user_mutex);

#ifdef DEBUG_STATS
printf("Thread ID Allocated Reused Discarded\n");
for (int i = 0; i < pool->scheduler->num_threads + 1; i++) {
printf("%02d %05d %05d %05d\n",
i,
pool->mempool_stats[i].num_alloc,
pool->mempool_stats[i].num_reuse,
pool->mempool_stats[i].num_discard);
}
MEM_freeN(pool->mempool_stats);
#endif

if (pool->use_local_tls) {
free_task_tls(&pool->local_tls);
}

MEM_freeN(pool);

BLI_threaded_malloc_end();
}

BLI_INLINE bool task_can_use_local_queues(TaskPool *pool, int thread_id)
{
return (thread_id != -1 && (thread_id != pool->thread_id \|\| pool->do_work));
}

static void task_pool_push(TaskPool *pool,
TaskRunFunction run,
void *taskdata,
bool free_taskdata,
TaskFreeFunction freedata,
TaskPriority priority,
int thread_id)
{
/* Allocate task and fill it's properties. */
Task *task = task_alloc(pool, thread_id);
task->run = run;
task->taskdata = taskdata;
task->free_taskdata = free_taskdata;
task->freedata = freedata;
task->pool = pool;
/* For suspended pools we put everything yo a global queue first
* and exit as soon as possible.
*
* This tasks will be moved to actual execution when pool is
* activated by work_and_wait().
*/
if (pool->is_suspended) {
BLI_addhead(&pool->suspended_queue, task);
atomic_fetch_and_add_z(&pool->num_suspended, 1);
return;
}
/* Populate to any local queue first, this is cheapest push ever. */
if (task_can_use_local_queues(pool, thread_id)) {
ASSERT_THREAD_ID(pool->scheduler, thread_id);
TaskThreadLocalStorage *tls = get_task_tls(pool, thread_id);
/* Try to push to a local execution queue.
* These tasks will be picked up next.
*/
if (tls->num_local_queue < LOCAL_QUEUE_SIZE) {
tls->local_queue[tls->num_local_queue] = task;
tls->num_local_queue++;
return;
}
/* If we are in the delayed tasks push mode, we push tasks to a
* temporary local queue first without any locks, and then move them
* to global execution queue with a single lock.
*/
if (tls->do_delayed_push && tls->num_delayed_queue < DELAYED_QUEUE_SIZE) {
tls->delayed_queue[tls->num_delayed_queue] = task;
tls->num_delayed_queue++;
return;
}
}
/* Do push to a global execution pool, slowest possible method,
* causes quite reasonable amount of threading overhead.
*/
task_scheduler_push(pool->scheduler, task, priority);
}

void BLI_task_pool_push_ex(TaskPool *pool,
TaskRunFunction run,
void *taskdata,
bool free_taskdata,
TaskFreeFunction freedata,
TaskPriority priority)
{
task_pool_push(pool, run, taskdata, free_taskdata, freedata, priority, -1);
}

void BLI_task_pool_push(
TaskPool pool, TaskRunFunction run, void taskdata, bool free_taskdata, TaskPriority priority)
{
BLI_task_pool_push_ex(pool, run, taskdata, free_taskdata, NULL, priority);
}

void BLI_task_pool_push_from_thread(TaskPool *pool,
TaskRunFunction run,
void *taskdata,
bool free_taskdata,
TaskPriority priority,
int thread_id)
{
task_pool_push(pool, run, taskdata, free_taskdata, NULL, priority, thread_id);
}

void BLI_task_pool_work_and_wait(TaskPool *pool)
{
TaskThreadLocalStorage *tls = get_task_tls(pool, pool->thread_id);
TaskScheduler *scheduler = pool->scheduler;

if (atomic_fetch_and_and_uint8((uint8_t *)&pool->is_suspended, 0)) {
if (pool->num_suspended) {
task_pool_num_increase(pool, pool->num_suspended);
BLI_mutex_lock(&scheduler->queue_mutex);

BLI_movelisttolist(&scheduler->queue, &pool->suspended_queue);

BLI_condition_notify_all(&scheduler->queue_cond);
BLI_mutex_unlock(&scheduler->queue_mutex);

pool->num_suspended = 0;
}
}

pool->do_work = true;

ASSERT_THREAD_ID(pool->scheduler, pool->thread_id);

handle_local_queue(tls, pool->thread_id);

BLI_mutex_lock(&pool->num_mutex);

while (pool->num != 0) {
Task task, work_task = NULL;
bool found_task = false;

BLI_mutex_unlock(&pool->num_mutex);

BLI_mutex_lock(&scheduler->queue_mutex);

/* find task from this pool. if we get a task from another pool,
* we can get into deadlock */

for (task = scheduler->queue.first; task; task = task->next) {
if (task->pool == pool) {
work_task = task;
found_task = true;
BLI_remlink(&scheduler->queue, task);
break;
}
}

BLI_mutex_unlock(&scheduler->queue_mutex);

/* if found task, do it, otherwise wait until other tasks are done */
if (found_task) {
/* run task */
BLI_assert(!tls->do_delayed_push);
work_task->run(pool, work_task->taskdata, pool->thread_id);
BLI_assert(!tls->do_delayed_push);

/* delete task */
task_free(pool, task, pool->thread_id);

/* Handle all tasks from local queue. */
handle_local_queue(tls, pool->thread_id);

/* notify pool task was done */
task_pool_num_decrease(pool, 1);
}

BLI_mutex_lock(&pool->num_mutex);
if (pool->num == 0) {
break;
}

if (!found_task) {
BLI_condition_wait(&pool->num_cond, &pool->num_mutex);
}
}

BLI_mutex_unlock(&pool->num_mutex);

BLI_assert(tls->num_local_queue == 0);
}

void BLI_task_pool_work_wait_and_reset(TaskPool *pool)
{
BLI_task_pool_work_and_wait(pool);

pool->do_work = false;
pool->is_suspended = pool->start_suspended;
}

void BLI_task_pool_cancel(TaskPool *pool)
{
pool->do_cancel = true;

task_scheduler_clear(pool->scheduler, pool);

/* wait until all entries are cleared */
BLI_mutex_lock(&pool->num_mutex);
while (pool->num) {
BLI_condition_wait(&pool->num_cond, &pool->num_mutex);
}
BLI_mutex_unlock(&pool->num_mutex);

pool->do_cancel = false;
}

bool BLI_task_pool_canceled(TaskPool *pool)
{
return pool->do_cancel;
}

void BLI_task_pool_userdata(TaskPool pool)
{
return pool->userdata;
}

ThreadMutex BLI_task_pool_user_mutex(TaskPool pool)
{
return &pool->user_mutex;
}

void BLI_task_pool_delayed_push_begin(TaskPool *pool, int thread_id)
{
if (task_can_use_local_queues(pool, thread_id)) {
ASSERT_THREAD_ID(pool->scheduler, thread_id);
TaskThreadLocalStorage *tls = get_task_tls(pool, thread_id);
tls->do_delayed_push = true;
}
}

void BLI_task_pool_delayed_push_end(TaskPool *pool, int thread_id)
{
if (task_can_use_local_queues(pool, thread_id)) {
ASSERT_THREAD_ID(pool->scheduler, thread_id);
TaskThreadLocalStorage *tls = get_task_tls(pool, thread_id);
BLI_assert(tls->do_delayed_push);
task_scheduler_push_all(pool->scheduler, pool, tls->delayed_queue, tls->num_delayed_queue);
tls->do_delayed_push = false;
tls->num_delayed_queue = 0;
}
}

/* Parallel range routines */		/* Parallel range routines */

/**		/**
*		*
* Main functions:		* Main functions:
* - #BLI_task_parallel_range		* - #BLI_task_parallel_range
* - #BLI_task_parallel_listbase (#ListBase - double linked list)		* - #BLI_task_parallel_listbase (#ListBase - double linked list)
*		*
▲ Show 20 Lines • Show All 293 Lines • ▼ Show 20 Lines	void BLI_task_parallel_range(const int start,
range_pool.num_tasks = num_tasks = min_ii(num_tasks,		range_pool.num_tasks = num_tasks = min_ii(num_tasks,
max_ii(1, (stop - start) / range_pool.chunk_size));		max_ii(1, (stop - start) / range_pool.chunk_size));

if (num_tasks == 1) {		if (num_tasks == 1) {
parallel_range_single_thread(&range_pool);		parallel_range_single_thread(&range_pool);
return;		return;
}		}

TaskPool *task_pool = range_pool.pool = BLI_task_pool_create_suspended(task_scheduler,		TaskPool *task_pool = range_pool.pool = BLI_task_pool_create_suspended(
&range_pool);		task_scheduler, &range_pool, TASK_PRIORITY_HIGH);

range_pool.current_state = &state;		range_pool.current_state = &state;

if (use_tls_data) {		if (use_tls_data) {
state.flatten_tls_storage = flatten_tls_storage = MALLOCA(tls_data_size * (size_t)num_tasks);		state.flatten_tls_storage = flatten_tls_storage = MALLOCA(tls_data_size * (size_t)num_tasks);
state.tls_data_size = tls_data_size;		state.tls_data_size = tls_data_size;
}		}

		const int thread_id = BLI_task_pool_creator_thread_id(task_pool);
for (i = 0; i < num_tasks; i++) {		for (i = 0; i < num_tasks; i++) {
if (use_tls_data) {		if (use_tls_data) {
void userdata_chunk_local = (char )flatten_tls_storage + (tls_data_size * (size_t)i);		void userdata_chunk_local = (char )flatten_tls_storage + (tls_data_size * (size_t)i);
memcpy(userdata_chunk_local, tls_data, tls_data_size);		memcpy(userdata_chunk_local, tls_data, tls_data_size);
}		}
/* Use this pool's pre-allocated tasks. */		/* Use this pool's pre-allocated tasks. */
BLI_task_pool_push_from_thread(task_pool,		BLI_task_pool_push_from_thread(
parallel_range_func,		task_pool, parallel_range_func, POINTER_FROM_INT(i), false, NULL, thread_id);
POINTER_FROM_INT(i),
false,
TASK_PRIORITY_HIGH,
task_pool->thread_id);
}		}

BLI_task_pool_work_and_wait(task_pool);		BLI_task_pool_work_and_wait(task_pool);
BLI_task_pool_free(task_pool);		BLI_task_pool_free(task_pool);

if (use_tls_data) {		if (use_tls_data) {
if (settings->func_finalize != NULL) {		if (settings->func_finalize != NULL) {
for (i = 0; i < num_tasks; i++) {		for (i = 0; i < num_tasks; i++) {
▲ Show 20 Lines • Show All 128 Lines • ▼ Show 20 Lines	state->flatten_tls_storage = userdata_chunk_array = MALLOCA(userdata_chunk_size *
(size_t)num_tasks);		(size_t)num_tasks);
for (int i = 0; i < num_tasks; i++) {		for (int i = 0; i < num_tasks; i++) {
void userdata_chunk_local = (char )userdata_chunk_array +		void userdata_chunk_local = (char )userdata_chunk_array +
(userdata_chunk_size * (size_t)i);		(userdata_chunk_size * (size_t)i);
memcpy(userdata_chunk_local, userdata_chunk, userdata_chunk_size);		memcpy(userdata_chunk_local, userdata_chunk, userdata_chunk_size);
}		}
}		}

TaskPool *task_pool = range_pool->pool = BLI_task_pool_create_suspended(task_scheduler,		TaskPool *task_pool = range_pool->pool = BLI_task_pool_create_suspended(
range_pool);		task_scheduler, range_pool, TASK_PRIORITY_HIGH);

range_pool->current_state = range_pool->parallel_range_states;		range_pool->current_state = range_pool->parallel_range_states;
		const int thread_id = BLI_task_pool_creator_thread_id(task_pool);
for (int i = 0; i < num_tasks; i++) {		for (int i = 0; i < num_tasks; i++) {
BLI_task_pool_push_from_thread(task_pool,		BLI_task_pool_push_from_thread(
parallel_range_func,		task_pool, parallel_range_func, POINTER_FROM_INT(i), false, NULL, thread_id);
POINTER_FROM_INT(i),
false,
TASK_PRIORITY_HIGH,
task_pool->thread_id);
}		}

BLI_task_pool_work_and_wait(task_pool);		BLI_task_pool_work_and_wait(task_pool);

BLI_assert(atomic_cas_ptr((void **)&range_pool->current_state, NULL, NULL) == NULL);		BLI_assert(atomic_cas_ptr((void **)&range_pool->current_state, NULL, NULL) == NULL);

/* Finalize all tasks. */		/* Finalize all tasks. */
for (TaskParallelRangeState *state = range_pool->parallel_range_states; state != NULL;		for (TaskParallelRangeState *state = range_pool->parallel_range_states; state != NULL;
state = state->next) {		state = state->next) {
const size_t userdata_chunk_size = state->tls_data_size;		const size_t userdata_chunk_size = state->tls_data_size;
void *userdata_chunk_array = state->flatten_tls_storage;		void *userdata_chunk_array = state->flatten_tls_storage;
UNUSED_VARS_NDEBUG(userdata_chunk_array);		UNUSED_VARS_NDEBUG(userdata_chunk_array);
if (userdata_chunk_size == 0) {		if (userdata_chunk_size == 0) {
BLI_assert(userdata_chunk_array == NULL);		BLI_assert(userdata_chunk_array == NULL);
continue;		continue;
}		}

if (state->func_finalize != NULL) {		if (state->func_finalize != NULL) {
BLI_task_pool_push_from_thread(task_pool,		BLI_task_pool_push_from_thread(
parallel_range_func_finalize,		task_pool, parallel_range_func_finalize, state, false, NULL, thread_id);
state,
false,
TASK_PRIORITY_HIGH,
task_pool->thread_id);
}		}
}		}

BLI_task_pool_work_and_wait(task_pool);		BLI_task_pool_work_and_wait(task_pool);
BLI_task_pool_free(task_pool);		BLI_task_pool_free(task_pool);
range_pool->pool = NULL;		range_pool->pool = NULL;

/* Cleanup all tasks. */		/* Cleanup all tasks. */
▲ Show 20 Lines • Show All 170 Lines • ▼ Show 20 Lines	static void task_parallel_iterator_do(const TaskParallelSettings *settings,
state->iter_shared.spin_lock = &spin_lock;		state->iter_shared.spin_lock = &spin_lock;

void *userdata_chunk = settings->userdata_chunk;		void *userdata_chunk = settings->userdata_chunk;
const size_t userdata_chunk_size = settings->userdata_chunk_size;		const size_t userdata_chunk_size = settings->userdata_chunk_size;
void *userdata_chunk_local = NULL;		void *userdata_chunk_local = NULL;
void *userdata_chunk_array = NULL;		void *userdata_chunk_array = NULL;
const bool use_userdata_chunk = (userdata_chunk_size != 0) && (userdata_chunk != NULL);		const bool use_userdata_chunk = (userdata_chunk_size != 0) && (userdata_chunk != NULL);

TaskPool *task_pool = BLI_task_pool_create_suspended(task_scheduler, state);		TaskPool *task_pool = BLI_task_pool_create_suspended(task_scheduler, state, TASK_PRIORITY_HIGH);

if (use_userdata_chunk) {		if (use_userdata_chunk) {
userdata_chunk_array = MALLOCA(userdata_chunk_size * num_tasks);		userdata_chunk_array = MALLOCA(userdata_chunk_size * num_tasks);
}		}

		const int thread_id = BLI_task_pool_creator_thread_id(task_pool);
for (size_t i = 0; i < num_tasks; i++) {		for (size_t i = 0; i < num_tasks; i++) {
if (use_userdata_chunk) {		if (use_userdata_chunk) {
userdata_chunk_local = (char )userdata_chunk_array + (userdata_chunk_size i);		userdata_chunk_local = (char )userdata_chunk_array + (userdata_chunk_size i);
memcpy(userdata_chunk_local, userdata_chunk, userdata_chunk_size);		memcpy(userdata_chunk_local, userdata_chunk, userdata_chunk_size);
}		}
/* Use this pool's pre-allocated tasks. */		/* Use this pool's pre-allocated tasks. */
BLI_task_pool_push_from_thread(task_pool,		BLI_task_pool_push_from_thread(
parallel_iterator_func,		task_pool, parallel_iterator_func, userdata_chunk_local, false, NULL, thread_id);
userdata_chunk_local,
false,
TASK_PRIORITY_HIGH,
task_pool->thread_id);
}		}

BLI_task_pool_work_and_wait(task_pool);		BLI_task_pool_work_and_wait(task_pool);
BLI_task_pool_free(task_pool);		BLI_task_pool_free(task_pool);

if (use_userdata_chunk) {		if (use_userdata_chunk) {
if (settings->func_finalize != NULL) {		if (settings->func_finalize != NULL) {
for (size_t i = 0; i < num_tasks; i++) {		for (size_t i = 0; i < num_tasks; i++) {
▲ Show 20 Lines • Show All 145 Lines • ▼ Show 20 Lines	if (!use_threading) {
for (void *item = BLI_mempool_iterstep(&iter); item != NULL;		for (void *item = BLI_mempool_iterstep(&iter); item != NULL;
item = BLI_mempool_iterstep(&iter)) {		item = BLI_mempool_iterstep(&iter)) {
func(userdata, item);		func(userdata, item);
}		}
return;		return;
}		}

task_scheduler = BLI_task_scheduler_get();		task_scheduler = BLI_task_scheduler_get();
task_pool = BLI_task_pool_create_suspended(task_scheduler, &state);		task_pool = BLI_task_pool_create_suspended(task_scheduler, &state, TASK_PRIORITY_HIGH);
num_threads = BLI_task_scheduler_num_threads(task_scheduler);		num_threads = BLI_task_scheduler_num_threads(task_scheduler);

/* The idea here is to prevent creating task for each of the loop iterations		/* The idea here is to prevent creating task for each of the loop iterations
* and instead have tasks which are evenly distributed across CPU cores and		* and instead have tasks which are evenly distributed across CPU cores and
* pull next item to be crunched using the threaded-aware BLI_mempool_iter.		* pull next item to be crunched using the threaded-aware BLI_mempool_iter.
*/		*/
num_tasks = num_threads + 2;		num_tasks = num_threads + 2;

state.userdata = userdata;		state.userdata = userdata;
state.func = func;		state.func = func;

BLI_mempool_iter *mempool_iterators = BLI_mempool_iter_threadsafe_create(mempool,		BLI_mempool_iter *mempool_iterators = BLI_mempool_iter_threadsafe_create(mempool,
(size_t)num_tasks);		(size_t)num_tasks);

		const int thread_id = BLI_task_pool_creator_thread_id(task_pool);
for (i = 0; i < num_tasks; i++) {		for (i = 0; i < num_tasks; i++) {
/* Use this pool's pre-allocated tasks. */		/* Use this pool's pre-allocated tasks. */
BLI_task_pool_push_from_thread(task_pool,		BLI_task_pool_push_from_thread(
parallel_mempool_func,		task_pool, parallel_mempool_func, &mempool_iterators[i], false, NULL, thread_id);
&mempool_iterators[i],
false,
TASK_PRIORITY_HIGH,
task_pool->thread_id);
}		}

BLI_task_pool_work_and_wait(task_pool);		BLI_task_pool_work_and_wait(task_pool);
BLI_task_pool_free(task_pool);		BLI_task_pool_free(task_pool);

BLI_mempool_iter_threadsafe_free(mempool_iterators);		BLI_mempool_iter_threadsafe_free(mempool_iterators);
}		}