Add mutex stress test

.github/workflows/nightly_run.yml

@@ -599,6 +599,11 @@ jobs:
         run: bash build.sh --sysroot "$SYSROOT_PATH"
         working-directory: ./core/iwasm/libraries/lib-wasi-threads/test/
 
+      - name: Build WASI thread stress tests
+        if: matrix.test_option == '$WASI_TEST_OPTIONS'
+        run: bash build.sh --sysroot "$SYSROOT_PATH"
+        working-directory: ./core/iwasm/libraries/lib-wasi-threads/stress-test/
+
       - name: build socket api tests
         if: matrix.test_option == '$WASI_TEST_OPTIONS'
         run: bash build.sh

core/iwasm/libraries/lib-wasi-threads/stress-test/build.sh

@@ -0,0 +1,65 @@
+#!/bin/bash
+
+#
+# Copyright (C) 2023 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+# SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+#
+
+set -eo pipefail
+CC=${CC:=/opt/wasi-sdk/bin/clang}
+WAMR_DIR=../../../../..
+
+show_usage() {
+    echo "Usage: $0 [--sysroot PATH_TO_SYSROOT]"
+    echo "--sysroot PATH_TO_SYSROOT specify to build with custom sysroot for wasi-libc"
+}
+
+while [[ $# -gt 0 ]]; do
+    key="$1"
+    case $key in
+        --sysroot)
+            sysroot_path="$2"
+            shift
+            shift
+            ;;
+        --help)
+            show_usage
+            exit
+            ;;
+        *)
+            echo "Unknown option: $1"
+            exit 1
+            ;;
+    esac
+done
+
+rm -rf *.wasm
+rm -rf *.aot
+
+for test_c in *.c; do
+    test_wasm="$(basename $test_c .c).wasm"
+
+    if [[ -n "$sysroot_path" ]]; then 
+        if [ ! -d "$sysroot_path" ]; then 
+            echo "Directory $sysroot_path  doesn't exist. Aborting"
+            exit 1
+        fi
+        sysroot_command="--sysroot $sysroot_path"
+    fi
+
+    echo "Compiling $test_c to $test_wasm"
+    $CC \
+        -target wasm32-wasi-threads \
+        -O2 \
+        -Wall \
+        -pthread \
+        -z stack-size=32768 \
+        -Wl,--export=__heap_base \
+        -Wl,--export=__data_end \
+        -Wl,--shared-memory,--max-memory=1966080 \
+        -Wl,--export=wasi_thread_start \
+        -Wl,--export=malloc \
+        -Wl,--export=free \
+        $sysroot_command \
+        $test_c -o $test_wasm
+done

core/iwasm/libraries/lib-wasi-threads/stress-test/errorcheck_mutex_stress_test.c

@@ -0,0 +1,27 @@
+/*
+ * Copyright (C) 2023 Amazon.com Inc. or its affiliates. All rights reserved.
+ * SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+ */
+
+#include <pthread.h>
+#include <errno.h>
+#include "mutex_common.h"
+
+int
+main()
+{
+    pthread_mutex_t mutex;
+
+    // Set mutex type to errorcheck. This type provides some additional checks
+    // (for example returns EDEADLK instead of deadlocking in some cases)
+    pthread_mutexattr_t mutex_attr;
+    pthread_mutexattr_init(&mutex_attr);
+    pthread_mutexattr_settype(&mutex_attr, PTHREAD_MUTEX_ERRORCHECK);
+
+    pthread_mutex_init(&mutex, &mutex_attr);
+    pthread_mutexattr_destroy(&mutex_attr);
+
+    run_common_tests(&mutex);
+    fprintf(stderr, "Errorcheck mutex test is completed\n");
+    pthread_mutex_destroy(&mutex);
+}

core/iwasm/libraries/lib-wasi-threads/stress-test/manifest.json

@@ -0,0 +1,3 @@
+{
+    "name": "lib-wasi-threads stress tests"
+}

core/iwasm/libraries/lib-wasi-threads/stress-test/mutex_common.h

@@ -0,0 +1,229 @@
+/*
+ * Copyright (C) 2023 Amazon.com Inc. or its affiliates. All rights reserved.
+ * SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+ */
+
+#ifndef MUTEX_COMMON_H
+#define MUTEX_COMMON_H
+
+#include <pthread.h>
+#include <stdio.h>
+#include <assert.h>
+#include <errno.h>
+#include <unistd.h>
+#include <stdbool.h>
+#include <time.h>
+#include <stdlib.h>
+#include <string.h>
+
+enum Constants {
+    NUM_ITER = 250000,
+    NUM_THREADS = 12,
+    NUM_RETRY = 8,
+    RETRY_SLEEP_TIME_US = 1000,
+};
+
+// We're counting how many times each thread was called using this array
+// Main thread is also counted here so we need to make arrays bigger
+typedef struct {
+    int tids[NUM_THREADS + 1];
+    int calls[NUM_THREADS + 1];
+} StatCollector;
+
+typedef struct {
+    pthread_mutex_t *mutex;
+    StatCollector stat;
+    int counter;
+    bool is_sleeping;
+} MutexCounter;
+
+// This enum defines whether thread should sleep to increase contention
+enum SleepState {
+    NON_SLEEP = 0,
+    SLEEP = 1,
+};
+
+void
+mutex_counter_init(MutexCounter *mutex_counter, pthread_mutex_t *mutex,
+                   enum SleepState is_sleeping)
+{
+    memset(mutex_counter, 0, sizeof(*mutex_counter));
+    mutex_counter->mutex = mutex;
+    mutex_counter->is_sleeping = is_sleeping;
+}
+
+// This function spawns the thread using exponential retries if it receives
+// EAGAIN
+static inline void
+spawn_thread(pthread_t *tid, void *func, void *arg)
+{
+    int status_code = -1;
+    int timeout_us = RETRY_SLEEP_TIME_US;
+    for (int tries = 0; status_code != 0 && tries < NUM_RETRY; ++tries) {
+        status_code = pthread_create(tid, NULL, (void *(*)(void *))func, arg);
+        assert(status_code == 0 || status_code == EAGAIN);
+        if (status_code == EAGAIN) {
+            usleep(timeout_us);
+            timeout_us *= 2;
+        }
+    }
+
+    assert(status_code == 0 && "Thread creation should succeed");
+}
+
+// This function adds tid to our stat
+static inline void
+add_to_stat(StatCollector *stat, int tid)
+{
+    int tid_num = 0;
+    for (; tid_num < NUM_THREADS + 1 && stat->tids[tid_num] != 0; ++tid_num) {
+        if (stat->tids[tid_num] == tid) {
+            stat->calls[tid_num]++;
+            return;
+        }
+    }
+
+    assert(tid_num < NUM_THREADS + 1);
+    stat->tids[tid_num] = tid;
+    stat->calls[tid_num] = 1;
+}
+
+// This function prints number of calls by TID
+static inline void
+print_stat(StatCollector *stat)
+{
+    fprintf(stderr, "Thread calls count by TID\n");
+    for (int i = 0; i < NUM_THREADS + 1; ++i) {
+        if (stat->tids[i] != 0) {
+            fprintf(stderr, "TID: %d; Calls: %d\n", stat->tids[i],
+                    stat->calls[i]);
+        }
+    }
+}
+
+// This function is run by the threads, it increases counter in a loop and then
+// sleeps after unlocking the mutex to provide better contention
+static inline void *
+inc_shared_variable(void *arg)
+{
+    MutexCounter *mutex_counter = (MutexCounter *)(arg);
+    int sleep_us = 0;
+    while (!pthread_mutex_lock(mutex_counter->mutex)
+           && mutex_counter->counter < NUM_ITER) {
+        mutex_counter->counter++;
+        add_to_stat(&mutex_counter->stat, (int)(pthread_self()));
+        if (mutex_counter->is_sleeping) {
+            sleep_us = rand() % 1000;
+        }
+
+        assert(pthread_mutex_unlock(mutex_counter->mutex) == 0
+               && "Should be able to unlock a mutex");
+        if (mutex_counter->is_sleeping) {
+            usleep(sleep_us);
+        }
+    }
+
+    assert(mutex_counter->counter == NUM_ITER);
+    assert(pthread_mutex_unlock(mutex_counter->mutex) == 0
+           && "Should be able to unlock the mutex after test execution");
+
+    return NULL;
+}
+
+// Locking and unlocking a mutex in a single thread.
+static inline void *
+same_thread_lock_unlock_test(void *mutex)
+{
+    for (int i = 0; i < NUM_ITER; ++i) {
+        assert(pthread_mutex_lock(mutex) == 0
+               && "Main thread should be able to lock a mutex");
+        assert(pthread_mutex_unlock(mutex) == 0
+               && "Main thread should be able to unlock a mutex");
+    }
+
+    return NULL;
+}
+
+// This function spawns a thread that locks and unlocks a mutex `NUM_ITER` times
+// in a row
+static inline void
+same_non_main_thread_lock_unlock_test(pthread_mutex_t *mutex)
+{
+    pthread_t tid = 0;
+    spawn_thread(&tid, same_thread_lock_unlock_test, mutex);
+
+    assert(tid != 0 && "TID can't be 0 after successful thread creation");
+    assert(pthread_join(tid, NULL) == 0
+           && "Thread should be joined successfully");
+}
+
+// This function checks basic contention between main and non-main thread
+// increasing the shared variable
+static inline void
+two_threads_inc_test(pthread_mutex_t *mutex)
+{
+    MutexCounter mutex_counter;
+    mutex_counter_init(&mutex_counter, mutex, false);
+
+    pthread_t tid = 0;
+    spawn_thread(&tid, inc_shared_variable, &mutex_counter);
+
+    assert(tid != 0 && "TID can't be 0 after successful thread creation");
+    inc_shared_variable(&mutex_counter);
+    assert(pthread_join(tid, NULL) == 0
+           && "Thread should be joined without errors");
+    assert(mutex_counter.counter == NUM_ITER);
+}
+
+// This function creates number of threads specified by NUM_THREADS and run
+// concurrent increasing of shared variable
+static inline void
+max_threads_inc_test(pthread_mutex_t *mutex, int threads_num,
+                     enum SleepState is_sleeping)
+{
+    MutexCounter mutex_counter;
+    mutex_counter_init(&mutex_counter, mutex, is_sleeping);
+
+    pthread_t tids[threads_num];
+    for (int i = 0; i < threads_num; ++i) {
+        spawn_thread(&tids[i], inc_shared_variable, &mutex_counter);
+    }
+
+    inc_shared_variable(&mutex_counter);
+
+    for (int i = 0; i < threads_num; ++i) {
+        assert(pthread_join(tids[i], NULL) == 0
+               && "Thread should be joined without errors");
+    }
+
+    print_stat(&mutex_counter.stat);
+}
+
+// This function just runs all the tests described above
+static inline void
+run_common_tests(pthread_mutex_t *mutex)
+{
+    srand(time(NULL));
+
+    fprintf(stderr, "Starting same_thread_lock_unlock_test test\n");
+    same_thread_lock_unlock_test(mutex);
+    fprintf(stderr, "Finished same_thread_lock_unlock_test test\n");
+
+    fprintf(stderr, "Starting same_non_main_thread_lock_unlock_test test\n");
+    same_non_main_thread_lock_unlock_test(mutex);
+    fprintf(stderr, "Finished same_non_main_thread_lock_unlock_test test\n");
+
+    fprintf(stderr, "Starting two_threads_inc_test test\n");
+    two_threads_inc_test(mutex);
+    fprintf(stderr, "Finished two_threads_inc_test test\n");
+
+    fprintf(stderr, "Starting max_threads_inc_test_sleep test\n");
+    max_threads_inc_test(mutex, NUM_THREADS, SLEEP);
+    fprintf(stderr, "Finished concurrent_inc sleep test\n");
+
+    fprintf(stderr, "Starting max_threads_inc_test_non_sleep test\n");
+    max_threads_inc_test(mutex, NUM_THREADS, NON_SLEEP);
+    fprintf(stderr, "Finished max_threads_inc_test test\n");
+}
+
+#endif // MUTEX_COMMON_H

core/iwasm/libraries/lib-wasi-threads/stress-test/normal_mutex_stress_test.c

@@ -0,0 +1,20 @@
+/*
+ * Copyright (C) 2023 Amazon.com Inc. or its affiliates. All rights reserved.
+ * SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+ */
+
+#include <pthread.h>
+#include <errno.h>
+#include "mutex_common.h"
+
+int
+main()
+{
+    pthread_mutex_t mutex;
+    pthread_mutex_init(&mutex, NULL);
+
+    run_common_tests(&mutex);
+
+    fprintf(stderr, "Normal mutex test is completed\n");
+    pthread_mutex_destroy(&mutex);
+}