| /* |
| * |
| * Copyright 2015 gRPC authors. |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| * |
| */ |
| |
| /* Test of gpr synchronization support. */ |
| |
| #include <grpc/support/alloc.h> |
| #include <grpc/support/log.h> |
| #include <grpc/support/sync.h> |
| #include <grpc/support/thd.h> |
| #include <grpc/support/time.h> |
| #include <stdio.h> |
| #include <stdlib.h> |
| #include "test/core/util/test_config.h" |
| |
| /* ==================Example use of interface=================== |
| |
| A producer-consumer queue of up to N integers, |
| illustrating the use of the calls in this interface. */ |
| |
| #define N 4 |
| |
| typedef struct queue { |
| gpr_cv non_empty; /* Signalled when length becomes non-zero. */ |
| gpr_cv non_full; /* Signalled when length becomes non-N. */ |
| gpr_mu mu; /* Protects all fields below. |
| (That is, except during initialization or |
| destruction, the fields below should be accessed |
| only by a thread that holds mu.) */ |
| int head; /* Index of head of queue 0..N-1. */ |
| int length; /* Number of valid elements in queue 0..N. */ |
| int elem[N]; /* elem[head .. head+length-1] are queue elements. */ |
| } queue; |
| |
| /* Initialize *q. */ |
| void queue_init(queue* q) { |
| gpr_mu_init(&q->mu); |
| gpr_cv_init(&q->non_empty); |
| gpr_cv_init(&q->non_full); |
| q->head = 0; |
| q->length = 0; |
| } |
| |
| /* Free storage associated with *q. */ |
| void queue_destroy(queue* q) { |
| gpr_mu_destroy(&q->mu); |
| gpr_cv_destroy(&q->non_empty); |
| gpr_cv_destroy(&q->non_full); |
| } |
| |
| /* Wait until there is room in *q, then append x to *q. */ |
| void queue_append(queue* q, int x) { |
| gpr_mu_lock(&q->mu); |
| /* To wait for a predicate without a deadline, loop on the negation of the |
| predicate, and use gpr_cv_wait(..., gpr_inf_future(GPR_CLOCK_REALTIME)) |
| inside the loop |
| to release the lock, wait, and reacquire on each iteration. Code that |
| makes the condition true should use gpr_cv_broadcast() on the |
| corresponding condition variable. The predicate must be on state |
| protected by the lock. */ |
| while (q->length == N) { |
| gpr_cv_wait(&q->non_full, &q->mu, gpr_inf_future(GPR_CLOCK_REALTIME)); |
| } |
| if (q->length == 0) { /* Wake threads blocked in queue_remove(). */ |
| /* It's normal to use gpr_cv_broadcast() or gpr_signal() while |
| holding the lock. */ |
| gpr_cv_broadcast(&q->non_empty); |
| } |
| q->elem[(q->head + q->length) % N] = x; |
| q->length++; |
| gpr_mu_unlock(&q->mu); |
| } |
| |
| /* If it can be done without blocking, append x to *q and return non-zero. |
| Otherwise return 0. */ |
| int queue_try_append(queue* q, int x) { |
| int result = 0; |
| if (gpr_mu_trylock(&q->mu)) { |
| if (q->length != N) { |
| if (q->length == 0) { /* Wake threads blocked in queue_remove(). */ |
| gpr_cv_broadcast(&q->non_empty); |
| } |
| q->elem[(q->head + q->length) % N] = x; |
| q->length++; |
| result = 1; |
| } |
| gpr_mu_unlock(&q->mu); |
| } |
| return result; |
| } |
| |
| /* Wait until the *q is non-empty or deadline abs_deadline passes. If the |
| queue is non-empty, remove its head entry, place it in *head, and return |
| non-zero. Otherwise return 0. */ |
| int queue_remove(queue* q, int* head, gpr_timespec abs_deadline) { |
| int result = 0; |
| gpr_mu_lock(&q->mu); |
| /* To wait for a predicate with a deadline, loop on the negation of the |
| predicate or until gpr_cv_wait() returns true. Code that makes |
| the condition true should use gpr_cv_broadcast() on the corresponding |
| condition variable. The predicate must be on state protected by the |
| lock. */ |
| while (q->length == 0 && !gpr_cv_wait(&q->non_empty, &q->mu, abs_deadline)) { |
| } |
| if (q->length != 0) { /* Queue is non-empty. */ |
| result = 1; |
| if (q->length == N) { /* Wake threads blocked in queue_append(). */ |
| gpr_cv_broadcast(&q->non_full); |
| } |
| *head = q->elem[q->head]; |
| q->head = (q->head + 1) % N; |
| q->length--; |
| } /* else deadline exceeded */ |
| gpr_mu_unlock(&q->mu); |
| return result; |
| } |
| |
| /* ------------------------------------------------- */ |
| /* Tests for gpr_mu and gpr_cv, and the queue example. */ |
| struct test { |
| int threads; /* number of threads */ |
| |
| int64_t iterations; /* number of iterations per thread */ |
| int64_t counter; |
| int thread_count; /* used to allocate thread ids */ |
| int done; /* threads not yet completed */ |
| int incr_step; /* how much to increment/decrement refcount each time */ |
| |
| gpr_mu mu; /* protects iterations, counter, thread_count, done */ |
| |
| gpr_cv cv; /* signalling depends on test */ |
| |
| gpr_cv done_cv; /* signalled when done == 0 */ |
| |
| queue q; |
| |
| gpr_stats_counter stats_counter; |
| |
| gpr_refcount refcount; |
| gpr_refcount thread_refcount; |
| gpr_event event; |
| }; |
| |
| /* Return pointer to a new struct test. */ |
| static struct test* test_new(int threads, int64_t iterations, int incr_step) { |
| struct test* m = static_cast<struct test*>(gpr_malloc(sizeof(*m))); |
| m->threads = threads; |
| m->iterations = iterations; |
| m->counter = 0; |
| m->thread_count = 0; |
| m->done = threads; |
| m->incr_step = incr_step; |
| gpr_mu_init(&m->mu); |
| gpr_cv_init(&m->cv); |
| gpr_cv_init(&m->done_cv); |
| queue_init(&m->q); |
| gpr_stats_init(&m->stats_counter, 0); |
| gpr_ref_init(&m->refcount, 0); |
| gpr_ref_init(&m->thread_refcount, threads); |
| gpr_event_init(&m->event); |
| return m; |
| } |
| |
| /* Return pointer to a new struct test. */ |
| static void test_destroy(struct test* m) { |
| gpr_mu_destroy(&m->mu); |
| gpr_cv_destroy(&m->cv); |
| gpr_cv_destroy(&m->done_cv); |
| queue_destroy(&m->q); |
| gpr_free(m); |
| } |
| |
| /* Create m->threads threads, each running (*body)(m) */ |
| static void test_create_threads(struct test* m, void (*body)(void* arg)) { |
| gpr_thd_id id; |
| int i; |
| for (i = 0; i != m->threads; i++) { |
| GPR_ASSERT(gpr_thd_new(&id, body, m, nullptr)); |
| } |
| } |
| |
| /* Wait until all threads report done. */ |
| static void test_wait(struct test* m) { |
| gpr_mu_lock(&m->mu); |
| while (m->done != 0) { |
| gpr_cv_wait(&m->done_cv, &m->mu, gpr_inf_future(GPR_CLOCK_REALTIME)); |
| } |
| gpr_mu_unlock(&m->mu); |
| } |
| |
| /* Get an integer thread id in the raneg 0..threads-1 */ |
| static int thread_id(struct test* m) { |
| int id; |
| gpr_mu_lock(&m->mu); |
| id = m->thread_count++; |
| gpr_mu_unlock(&m->mu); |
| return id; |
| } |
| |
| /* Indicate that a thread is done, by decrementing m->done |
| and signalling done_cv if m->done==0. */ |
| static void mark_thread_done(struct test* m) { |
| gpr_mu_lock(&m->mu); |
| GPR_ASSERT(m->done != 0); |
| m->done--; |
| if (m->done == 0) { |
| gpr_cv_signal(&m->done_cv); |
| } |
| gpr_mu_unlock(&m->mu); |
| } |
| |
| /* Test several threads running (*body)(struct test *m) for increasing settings |
| of m->iterations, until about timeout_s to 2*timeout_s seconds have elapsed. |
| If extra!=NULL, run (*extra)(m) in an additional thread. |
| incr_step controls by how much m->refcount should be incremented/decremented |
| (if at all) each time in the tests. |
| */ |
| static void test(const char* name, void (*body)(void* m), |
| void (*extra)(void* m), int timeout_s, int incr_step) { |
| int64_t iterations = 1024; |
| struct test* m; |
| gpr_timespec start = gpr_now(GPR_CLOCK_REALTIME); |
| gpr_timespec time_taken; |
| gpr_timespec deadline = gpr_time_add( |
| start, gpr_time_from_micros((int64_t)timeout_s * 1000000, GPR_TIMESPAN)); |
| fprintf(stderr, "%s:", name); |
| while (gpr_time_cmp(gpr_now(GPR_CLOCK_REALTIME), deadline) < 0) { |
| iterations <<= 1; |
| fprintf(stderr, " %ld", (long)iterations); |
| m = test_new(10, iterations, incr_step); |
| if (extra != nullptr) { |
| gpr_thd_id id; |
| GPR_ASSERT(gpr_thd_new(&id, extra, m, nullptr)); |
| m->done++; /* one more thread to wait for */ |
| } |
| test_create_threads(m, body); |
| test_wait(m); |
| if (m->counter != m->threads * m->iterations * m->incr_step) { |
| fprintf(stderr, "counter %ld threads %d iterations %ld\n", |
| (long)m->counter, m->threads, (long)m->iterations); |
| GPR_ASSERT(0); |
| } |
| test_destroy(m); |
| } |
| time_taken = gpr_time_sub(gpr_now(GPR_CLOCK_REALTIME), start); |
| fprintf(stderr, " done %lld.%09d s\n", (long long)time_taken.tv_sec, |
| (int)time_taken.tv_nsec); |
| } |
| |
| /* Increment m->counter on each iteration; then mark thread as done. */ |
| static void inc(void* v /*=m*/) { |
| struct test* m = static_cast<struct test*>(v); |
| int64_t i; |
| for (i = 0; i != m->iterations; i++) { |
| gpr_mu_lock(&m->mu); |
| m->counter++; |
| gpr_mu_unlock(&m->mu); |
| } |
| mark_thread_done(m); |
| } |
| |
| /* Increment m->counter under lock acquired with trylock, m->iterations times; |
| then mark thread as done. */ |
| static void inctry(void* v /*=m*/) { |
| struct test* m = static_cast<struct test*>(v); |
| int64_t i; |
| for (i = 0; i != m->iterations;) { |
| if (gpr_mu_trylock(&m->mu)) { |
| m->counter++; |
| gpr_mu_unlock(&m->mu); |
| i++; |
| } |
| } |
| mark_thread_done(m); |
| } |
| |
| /* Increment counter only when (m->counter%m->threads)==m->thread_id; then mark |
| thread as done. */ |
| static void inc_by_turns(void* v /*=m*/) { |
| struct test* m = static_cast<struct test*>(v); |
| int64_t i; |
| int id = thread_id(m); |
| for (i = 0; i != m->iterations; i++) { |
| gpr_mu_lock(&m->mu); |
| while ((m->counter % m->threads) != id) { |
| gpr_cv_wait(&m->cv, &m->mu, gpr_inf_future(GPR_CLOCK_REALTIME)); |
| } |
| m->counter++; |
| gpr_cv_broadcast(&m->cv); |
| gpr_mu_unlock(&m->mu); |
| } |
| mark_thread_done(m); |
| } |
| |
| /* Wait a millisecond and increment counter on each iteration; |
| then mark thread as done. */ |
| static void inc_with_1ms_delay(void* v /*=m*/) { |
| struct test* m = static_cast<struct test*>(v); |
| int64_t i; |
| for (i = 0; i != m->iterations; i++) { |
| gpr_timespec deadline; |
| gpr_mu_lock(&m->mu); |
| deadline = gpr_time_add(gpr_now(GPR_CLOCK_REALTIME), |
| gpr_time_from_micros(1000, GPR_TIMESPAN)); |
| while (!gpr_cv_wait(&m->cv, &m->mu, deadline)) { |
| } |
| m->counter++; |
| gpr_mu_unlock(&m->mu); |
| } |
| mark_thread_done(m); |
| } |
| |
| /* Wait a millisecond and increment counter on each iteration, using an event |
| for timing; then mark thread as done. */ |
| static void inc_with_1ms_delay_event(void* v /*=m*/) { |
| struct test* m = static_cast<struct test*>(v); |
| int64_t i; |
| for (i = 0; i != m->iterations; i++) { |
| gpr_timespec deadline; |
| deadline = gpr_time_add(gpr_now(GPR_CLOCK_REALTIME), |
| gpr_time_from_micros(1000, GPR_TIMESPAN)); |
| GPR_ASSERT(gpr_event_wait(&m->event, deadline) == nullptr); |
| gpr_mu_lock(&m->mu); |
| m->counter++; |
| gpr_mu_unlock(&m->mu); |
| } |
| mark_thread_done(m); |
| } |
| |
| /* Produce m->iterations elements on queue m->q, then mark thread as done. |
| Even threads use queue_append(), and odd threads use queue_try_append() |
| until it succeeds. */ |
| static void many_producers(void* v /*=m*/) { |
| struct test* m = static_cast<struct test*>(v); |
| int64_t i; |
| int x = thread_id(m); |
| if ((x & 1) == 0) { |
| for (i = 0; i != m->iterations; i++) { |
| queue_append(&m->q, 1); |
| } |
| } else { |
| for (i = 0; i != m->iterations; i++) { |
| while (!queue_try_append(&m->q, 1)) { |
| } |
| } |
| } |
| mark_thread_done(m); |
| } |
| |
| /* Consume elements from m->q until m->threads*m->iterations are seen, |
| wait an extra second to confirm that no more elements are arriving, |
| then mark thread as done. */ |
| static void consumer(void* v /*=m*/) { |
| struct test* m = static_cast<struct test*>(v); |
| int64_t n = m->iterations * m->threads; |
| int64_t i; |
| int value; |
| for (i = 0; i != n; i++) { |
| queue_remove(&m->q, &value, gpr_inf_future(GPR_CLOCK_REALTIME)); |
| } |
| gpr_mu_lock(&m->mu); |
| m->counter = n; |
| gpr_mu_unlock(&m->mu); |
| GPR_ASSERT( |
| !queue_remove(&m->q, &value, |
| gpr_time_add(gpr_now(GPR_CLOCK_REALTIME), |
| gpr_time_from_micros(1000000, GPR_TIMESPAN)))); |
| mark_thread_done(m); |
| } |
| |
| /* Increment m->stats_counter m->iterations times, transfer counter value to |
| m->counter, then mark thread as done. */ |
| static void statsinc(void* v /*=m*/) { |
| struct test* m = static_cast<struct test*>(v); |
| int64_t i; |
| for (i = 0; i != m->iterations; i++) { |
| gpr_stats_inc(&m->stats_counter, 1); |
| } |
| gpr_mu_lock(&m->mu); |
| m->counter = gpr_stats_read(&m->stats_counter); |
| gpr_mu_unlock(&m->mu); |
| mark_thread_done(m); |
| } |
| |
| /* Increment m->refcount by m->incr_step for m->iterations times. Decrement |
| m->thread_refcount once, and if it reaches zero, set m->event to (void*)1; |
| then mark thread as done. */ |
| static void refinc(void* v /*=m*/) { |
| struct test* m = static_cast<struct test*>(v); |
| int64_t i; |
| for (i = 0; i != m->iterations; i++) { |
| if (m->incr_step == 1) { |
| gpr_ref(&m->refcount); |
| } else { |
| gpr_refn(&m->refcount, m->incr_step); |
| } |
| } |
| if (gpr_unref(&m->thread_refcount)) { |
| gpr_event_set(&m->event, (void*)1); |
| } |
| mark_thread_done(m); |
| } |
| |
| /* Wait until m->event is set to (void *)1, then decrement m->refcount by 1 |
| (m->threads * m->iterations * m->incr_step) times, and ensure that the last |
| decrement caused the counter to reach zero, then mark thread as done. */ |
| static void refcheck(void* v /*=m*/) { |
| struct test* m = static_cast<struct test*>(v); |
| int64_t n = m->iterations * m->threads * m->incr_step; |
| int64_t i; |
| GPR_ASSERT(gpr_event_wait(&m->event, gpr_inf_future(GPR_CLOCK_REALTIME)) == |
| (void*)1); |
| GPR_ASSERT(gpr_event_get(&m->event) == (void*)1); |
| for (i = 1; i != n; i++) { |
| GPR_ASSERT(!gpr_unref(&m->refcount)); |
| m->counter++; |
| } |
| GPR_ASSERT(gpr_unref(&m->refcount)); |
| m->counter++; |
| mark_thread_done(m); |
| } |
| |
| /* ------------------------------------------------- */ |
| |
| int main(int argc, char* argv[]) { |
| grpc_test_init(argc, argv); |
| test("mutex", &inc, nullptr, 1, 1); |
| test("mutex try", &inctry, nullptr, 1, 1); |
| test("cv", &inc_by_turns, nullptr, 1, 1); |
| test("timedcv", &inc_with_1ms_delay, nullptr, 1, 1); |
| test("queue", &many_producers, &consumer, 10, 1); |
| test("stats_counter", &statsinc, nullptr, 1, 1); |
| test("refcount by 1", &refinc, &refcheck, 1, 1); |
| test("refcount by 3", &refinc, &refcheck, 1, 3); /* incr_step of 3 is an |
| arbitrary choice. Any |
| number > 1 is okay here */ |
| test("timedevent", &inc_with_1ms_delay_event, nullptr, 1, 1); |
| return 0; |
| } |