Index: uspace/app/rcubench/Makefile =================================================================== --- uspace/app/rcubench/Makefile (revision 2a5d1751090211ae7f388acdeff5287ff75e2b8f) +++ uspace/app/rcubench/Makefile (revision 2a5d1751090211ae7f388acdeff5287ff75e2b8f) @@ -0,0 +1,41 @@ +# +# Copyright (c) 2012 Adam Hraska +# All rights reserved. +# +# Redistribution and use in source and binary forms, with or without +# modification, are permitted provided that the following conditions +# are met: +# +# - Redistributions of source code must retain the above copyright +# notice, this list of conditions and the following disclaimer. +# - Redistributions in binary form must reproduce the above copyright +# notice, this list of conditions and the following disclaimer in the +# documentation and/or other materials provided with the distribution. +# - The name of the author may not be used to endorse or promote products +# derived from this software without specific prior written permission. +# +# THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR +# IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES +# OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. +# IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, +# INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT +# NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, +# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY +# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT +# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF +# THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. +# + +USPACE_PREFIX = ../.. + +LIBS = $(LIBURCU_PREFIX)/liburcu.a + +EXTRA_CFLAGS += -I$(LIBURCU_PREFIX) + +BINARY = rcubench + +SOURCES = \ + rcubench.c + +include $(USPACE_PREFIX)/Makefile.common + Index: uspace/app/rcubench/rcubench.c =================================================================== --- uspace/app/rcubench/rcubench.c (revision 2a5d1751090211ae7f388acdeff5287ff75e2b8f) +++ uspace/app/rcubench/rcubench.c (revision 2a5d1751090211ae7f388acdeff5287ff75e2b8f) @@ -0,0 +1,288 @@ +/* + * Copyright (c) 2012 Adam Hraska + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * + * - Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * - Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * - The name of the author may not be used to endorse or promote products + * derived from this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR + * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES + * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. + * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT + * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF + * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ + +/** @addtogroup test + * @{ + */ + +/** + * @file rcubench.c + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include + + +/* Results are printed to this file in addition to stdout. */ +static FILE *results_fd = NULL; + +typedef struct bench { + const char *name; + void (*func)(struct bench *); + size_t iters; + size_t nthreads; + futex_t done_threads; + + futex_t bench_fut; +} bench_t; + + + + +static void kernel_futex_bench(bench_t *bench) +{ + const size_t iters = bench->iters; + int val = 0; + + for (size_t i = 0; i < iters; ++i) { + __SYSCALL1(SYS_FUTEX_WAKEUP, (sysarg_t) &val); + __SYSCALL1(SYS_FUTEX_SLEEP, (sysarg_t) &val); + } +} + +static void libc_futex_lock_bench(bench_t *bench) +{ + const size_t iters = bench->iters; + futex_t loc_fut = FUTEX_INITIALIZER; + + for (size_t i = 0; i < iters; ++i) { + futex_lock(&loc_fut); + /* no-op */ + compiler_barrier(); + futex_unlock(&loc_fut); + } +} + +static void libc_futex_sema_bench(bench_t *bench) +{ + const size_t iters = bench->iters; + futex_t loc_fut = FUTEX_INITIALIZER; + + for (size_t i = 0; i < iters; ++i) { + futex_down(&loc_fut); + /* no-op */ + compiler_barrier(); + futex_up(&loc_fut); + } +} + +static void thread_func(void *arg) +{ + bench_t *bench = (bench_t*)arg; + + bench->func(bench); + + /* Signal another thread completed. */ + futex_up(&bench->done_threads); +} + +static void run_threads_and_wait(bench_t *bench) +{ + assert(1 <= bench->nthreads); + + if (2 <= bench->nthreads) { + printf("Creating %zu additional threads...\n", bench->nthreads - 1); + } + + /* Create and run the first nthreads - 1 threads.*/ + for (size_t k = 1; k < bench->nthreads; ++k) { + thread_id_t tid; + /* Also sets up a fibril for the thread. */ + int ret = thread_create(thread_func, bench, "rcubench-t", &tid); + if (ret != EOK) { + printf("Error: Failed to create benchmark thread.\n"); + abort(); + } + thread_detach(tid); + } + + /* + * Run the last thread in place so that we create multiple threads + * only when needed. Otherwise libc would immediately upgrade + * single-threaded futexes to proper multithreaded futexes + */ + thread_func(bench); + + printf("Waiting for remaining threads to complete.\n"); + + /* Wait for threads to complete. */ + for (size_t k = 0; k < bench->nthreads; ++k) { + futex_down(&bench->done_threads); + } +} + +static const char *results_txt = "/tmp/urcu-bench-results.txt"; + +static bool open_results(void) +{ + results_fd = fopen(results_txt, "a"); + return NULL != results_fd; +} + +static void close_results(void) +{ + if (results_fd) { + fclose(results_fd); + } +} + +static void print_res(const char *fmt, ... ) +{ + va_list args; + + va_start(args, fmt); + vfprintf(results_fd, fmt, args); + va_end(args); + + va_start(args, fmt); + vprintf(fmt, args); + va_end(args); +} + +static void print_usage(void) +{ + printf("rcubench [test-name] [k-iterations] [n-threads]\n"); + printf("Available tests: \n"); + printf(" sys-futex.. threads make wakeup/sleepdown futex syscalls in a loop\n"); + printf(" but for separate variables/futex kernel objects.\n"); + printf(" lock .. threads lock/unlock separate futexes.\n"); + printf(" sema .. threads down/up separate futexes.\n"); + printf("eg:\n"); + printf(" rcubench sys-futex 100000 3\n"); + printf(" rcubench lock 100000 2 ..runs futex_lock/unlock in a loop\n"); + printf(" rcubench sema 100000 2 ..runs futex_down/up in a loop\n"); + printf("Results are stored in %s\n", results_txt); +} + +static bool parse_cmd_line(int argc, char **argv, bench_t *bench, + const char **err) +{ + if (argc < 4) { + *err = "Not enough parameters"; + return false; + } + + futex_initialize(&bench->bench_fut, 1); + + if (0 == str_cmp(argv[1], "sys-futex")) { + bench->func = kernel_futex_bench; + } else if (0 == str_cmp(argv[1], "lock")) { + bench->func = libc_futex_lock_bench; + } else if (0 == str_cmp(argv[1], "sema")) { + bench->func = libc_futex_sema_bench; + } else { + *err = "Unknown test name"; + return false; + } + + bench->name = argv[1]; + + /* Determine iteration count. */ + uint32_t iter_cnt = 0; + int ret = str_uint32_t(argv[2], NULL, 0, true, &iter_cnt); + + if (ret == EOK && 1 <= iter_cnt) { + bench->iters = iter_cnt; + } else { + *err = "Err: Invalid number of iterations"; + return false; + } + + /* Determine thread count. */ + uint32_t thread_cnt = 0; + ret = str_uint32_t(argv[3], NULL, 0, true, &thread_cnt); + + if (ret == EOK && 1 <= thread_cnt && thread_cnt <= 64) { + bench->nthreads = thread_cnt; + } else { + *err = "Err: Invalid number of threads"; + return false; + } + + return true; +} + +int main(int argc, char **argv) +{ + const char *err = "(error)"; + bench_t bench; + + futex_initialize(&bench.done_threads, 0); + + if (!parse_cmd_line(argc, argv, &bench, &err)) { + printf("%s\n", err); + print_usage(); + return -1; + } + + open_results(); + + print_res("Running '%s' futex bench in '%zu' threads with '%zu' iterations.\n", + bench.name, bench.nthreads, bench.iters); + + struct timeval start, end; + getuptime(&start); + + run_threads_and_wait(&bench); + + getuptime(&end); + int64_t duration = tv_sub(&end, &start); + + uint64_t secs = (uint64_t)duration / 1000 / 1000; + uint64_t total_iters = (uint64_t)bench.iters * bench.nthreads; + uint64_t iters_per_sec = 0; + + if (0 < duration) { + iters_per_sec = total_iters * 1000 * 1000 / duration; + } + + print_res("Completed %" PRIu64 " iterations in %" PRId64 " usecs (%" PRIu64 + " secs); %" PRIu64 " iters/sec\n", + total_iters, duration, secs, iters_per_sec); + + close_results(); + + return 0; +} + + +/** + * @} + */ Index: uspace/app/rcutest/Makefile =================================================================== --- uspace/app/rcutest/Makefile (revision 2a5d1751090211ae7f388acdeff5287ff75e2b8f) +++ uspace/app/rcutest/Makefile (revision 2a5d1751090211ae7f388acdeff5287ff75e2b8f) @@ -0,0 +1,41 @@ +# +# Copyright (c) 2012 Adam Hraska +# All rights reserved. +# +# Redistribution and use in source and binary forms, with or without +# modification, are permitted provided that the following conditions +# are met: +# +# - Redistributions of source code must retain the above copyright +# notice, this list of conditions and the following disclaimer. +# - Redistributions in binary form must reproduce the above copyright +# notice, this list of conditions and the following disclaimer in the +# documentation and/or other materials provided with the distribution. +# - The name of the author may not be used to endorse or promote products +# derived from this software without specific prior written permission. +# +# THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR +# IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES +# OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. +# IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, +# INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT +# NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, +# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY +# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT +# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF +# THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. +# + +USPACE_PREFIX = ../.. + +LIBS = $(LIBURCU_PREFIX)/liburcu.a + +EXTRA_CFLAGS += -I$(LIBURCU_PREFIX) + +BINARY = rcutest + +SOURCES = \ + rcutest.c + +include $(USPACE_PREFIX)/Makefile.common + Index: uspace/app/rcutest/rcutest.c =================================================================== --- uspace/app/rcutest/rcutest.c (revision 2a5d1751090211ae7f388acdeff5287ff75e2b8f) +++ uspace/app/rcutest/rcutest.c (revision 2a5d1751090211ae7f388acdeff5287ff75e2b8f) @@ -0,0 +1,909 @@ +/* + * Copyright (c) 2012 Adam Hraska + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * + * - Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * - Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * - The name of the author may not be used to endorse or promote products + * derived from this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR + * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES + * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. + * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT + * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF + * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ + +/** @addtogroup test + * @{ + */ + +/** + * @file rcutest.c + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include + + + +#define USECS_PER_SEC (1000 * 1000) +#define USECS_PER_MS 1000 + +/* fwd decl. */ +struct test_info; + +typedef struct test_desc { + /* Aggregate test that runs other tests already in the table test_desc. */ + bool aggregate; + enum { + T_OTHER, + T_SANITY, + T_STRESS + } type; + bool (*func)(struct test_info*); + const char *name; + const char *desc; +} test_desc_t; + + +typedef struct test_info { + size_t thread_cnt; + test_desc_t *desc; +} test_info_t; + + + +static bool run_all_tests(struct test_info*); +static bool run_sanity_tests(struct test_info*); +static bool run_stress_tests(struct test_info*); + +static bool wait_for_one_reader(struct test_info*); +static bool basic_sanity_check(struct test_info*); +static bool dont_wait_for_new_reader(struct test_info*); +static bool wait_for_exiting_reader(struct test_info*); +static bool seq_test(struct test_info*); + + +static test_desc_t test_desc[] = { + { + .aggregate = true, + .type = T_OTHER, + .func = run_all_tests, + .name = "*", + .desc = "Runs all tests.", + }, + { + .aggregate = true, + .type = T_SANITY, + .func = run_sanity_tests, + .name = "sanity-tests", + .desc = "Runs all RCU sanity tests.", + }, + { + .aggregate = true, + .type = T_STRESS, + .func = run_stress_tests, + .name = "stress-tests", + .desc = "Runs all RCU stress tests.", + }, + + { + .aggregate = false, + .type = T_SANITY, + .func = basic_sanity_check, + .name = "basic-sanity", + .desc = "Locks/unlocks and syncs in 1 fibril, no contention.", + }, + { + .aggregate = false, + .type = T_SANITY, + .func = wait_for_one_reader, + .name = "wait-for-one", + .desc = "Syncs with one 2 secs sleeping reader.", + }, + { + .aggregate = false, + .type = T_SANITY, + .func = dont_wait_for_new_reader, + .name = "ignore-new-r", + .desc = "Syncs with preexisting reader; ignores new reader.", + }, + { + .aggregate = false, + .type = T_SANITY, + .func = wait_for_exiting_reader, + .name = "dereg-unlocks", + .desc = "Lets deregister_fibril unlock the reader section.", + }, + { + .aggregate = false, + .type = T_STRESS, + .func = seq_test, + .name = "seq", + .desc = "Checks lock/unlock/sync w/ global time sequence.", + }, + { + .aggregate = false, + .type = T_OTHER, + .func = NULL, + .name = "(null)", + .desc = "", + }, +}; + +static const size_t test_desc_cnt = sizeof(test_desc) / sizeof(test_desc[0]); + +/*--------------------------------------------------------------------*/ + +static size_t next_rand(size_t seed) +{ + return (seed * 1103515245 + 12345) & ((1U << 31) - 1); +} + + +typedef int (*fibril_func_t)(void *); + +static bool create_fibril(int (*func)(void*), void *arg) +{ + fid_t fid = fibril_create(func, arg); + + if (0 == fid) { + printf("Failed to create a fibril!\n"); + return false; + } + + fibril_add_ready(fid); + return true; +} + +/*--------------------------------------------------------------------*/ + +static bool run_tests(test_info_t *info, bool (*include_filter)(test_desc_t *)) +{ + size_t failed_cnt = 0; + size_t ok_cnt = 0; + + for (size_t i = 0; i < test_desc_cnt; ++i) { + test_desc_t *t = &test_desc[i]; + + if (t->func && !t->aggregate && include_filter(t)) { + printf("Running \'%s\'...\n", t->name); + bool ok = test_desc[i].func(info); + + if (ok) { + ++ok_cnt; + printf("Passed: \'%s\'\n", t->name); + } else { + ++failed_cnt; + printf("FAILED: \'%s\'\n", t->name); + } + } + } + + printf("\n"); + + printf("%zu tests passed\n", ok_cnt); + + if (failed_cnt) { + printf("%zu tests failed\n", failed_cnt); + } + + return 0 == failed_cnt; +} + +/*--------------------------------------------------------------------*/ + +static bool all_tests_include_filter(test_desc_t *desc) +{ + return true; +} + +/* Runs all available tests tests one-by-one. */ +static bool run_all_tests(test_info_t *test_info) +{ + printf("Running all tests...\n"); + return run_tests(test_info, all_tests_include_filter); +} + +/*--------------------------------------------------------------------*/ + +static bool stress_tests_include_filter(test_desc_t *desc) +{ + return desc->type == T_STRESS; +} + +/* Runs all available stress tests one-by-one. */ +static bool run_stress_tests(test_info_t *test_info) +{ + printf("Running stress tests...\n"); + return run_tests(test_info, stress_tests_include_filter); +} + +/*--------------------------------------------------------------------*/ + +static bool sanity_tests_include_filter(test_desc_t *desc) +{ + return desc->type == T_SANITY; +} + +/* Runs all available sanity tests one-by-one. */ +static bool run_sanity_tests(test_info_t *test_info) +{ + printf("Running sanity tests...\n"); + return run_tests(test_info, sanity_tests_include_filter); +} + +/*--------------------------------------------------------------------*/ + +/* Locks/unlocks rcu and synchronizes without contention in a single fibril. */ +static bool basic_sanity_check(test_info_t *test_info) +{ + rcu_read_lock(); + /* nop */ + rcu_read_unlock(); + + rcu_read_lock(); + /* nop */ + rcu_read_unlock(); + + rcu_synchronize(); + + /* Nested lock with yield(). */ + rcu_read_lock(); + fibril_yield(); + rcu_read_lock(); + fibril_yield(); + rcu_read_unlock(); + fibril_yield(); + rcu_read_unlock(); + + fibril_yield(); + rcu_synchronize(); + rcu_synchronize(); + + rcu_read_lock(); + /* nop */ + if (!rcu_read_locked()) + return false; + + rcu_read_unlock(); + + return !rcu_read_locked(); +} + +typedef struct one_reader_info { + bool entered_cs; + bool exited_cs; + size_t done_sleeps_cnt; + bool synching; + bool synched; + size_t failed; +} one_reader_info_t; + + +static int sleeping_reader(one_reader_info_t *arg) +{ + rcu_register_fibril(); + + printf("lock{"); + rcu_read_lock(); + rcu_read_lock(); + arg->entered_cs = true; + rcu_read_unlock(); + + printf("r-sleep{"); + /* 2 sec */ + async_usleep(2 * USECS_PER_SEC); + ++arg->done_sleeps_cnt; + printf("}"); + + if (arg->synched) { + arg->failed = 1; + printf("Error: rcu_sync exited prematurely.\n"); + } + + arg->exited_cs = true; + rcu_read_unlock(); + printf("}"); + + rcu_deregister_fibril(); + return 0; +} + +static bool wait_for_one_reader(test_info_t *test_info) +{ + one_reader_info_t info = { 0 }; + + if (!create_fibril((fibril_func_t) sleeping_reader, &info)) + return false; + + /* 1 sec, waits for the reader to enter its critical section and sleep. */ + async_usleep(1 * USECS_PER_SEC); + + if (!info.entered_cs || info.exited_cs) { + printf("Error: reader is unexpectedly outside of critical section.\n"); + return false; + } + + info.synching = true; + printf("sync["); + rcu_synchronize(); + printf("]\n"); + info.synched = true; + + /* Load info.exited_cs */ + memory_barrier(); + + if (!info.exited_cs || info.failed) { + printf("Error: rcu_sync() returned before the reader exited its CS.\n"); + /* + * Sleep some more so we don't free info on stack while the reader + * is using it. + */ + /* 1.5 sec */ + async_usleep(1500 * 1000); + return false; + } else { + return true; + } +} + +/*--------------------------------------------------------------------*/ + +#define WAIT_STEP_US 500 * USECS_PER_MS + +typedef struct two_reader_info { + bool new_entered_cs; + bool new_exited_cs; + bool old_entered_cs; + bool old_exited_cs; + bool synching; + bool synched; + size_t failed; +} two_reader_info_t; + + +static int preexisting_reader(two_reader_info_t *arg) +{ + rcu_register_fibril(); + + printf("old-lock{"); + rcu_read_lock(); + arg->old_entered_cs = true; + + printf("wait-for-sync{"); + /* Wait for rcu_sync() to start waiting for us. */ + while (!arg->synching) { + async_usleep(WAIT_STEP_US); + } + printf(" }"); + + /* A new reader starts while rcu_sync() is in progress. */ + + printf("wait-for-new-R{"); + /* Wait for the new reader to enter its reader section. */ + while (!arg->new_entered_cs) { + async_usleep(WAIT_STEP_US); + } + printf(" }"); + + arg->old_exited_cs = true; + + assert(!arg->new_exited_cs); + + if (arg->synched) { + arg->failed = 1; + printf("Error: rcu_sync() did not wait for preexisting reader.\n"); + } + + rcu_read_unlock(); + printf(" }"); + + rcu_deregister_fibril(); + return 0; +} + +static int new_reader(two_reader_info_t *arg) +{ + rcu_register_fibril(); + + /* Wait until rcu_sync() starts. */ + while (!arg->synching) { + async_usleep(WAIT_STEP_US); + } + + /* + * synching is set when rcu_sync() is about to be entered so wait + * some more to make sure it really does start executing. + */ + async_usleep(WAIT_STEP_US); + + printf("new-lock("); + rcu_read_lock(); + arg->new_entered_cs = true; + + /* Wait for rcu_sync() exit, ie stop waiting for the preexisting reader. */ + while (!arg->synched) { + async_usleep(WAIT_STEP_US); + } + + arg->new_exited_cs = true; + /* Write new_exited_cs before exiting reader section. */ + memory_barrier(); + + /* + * Preexisting reader should have exited by now, so rcu_synchronize() + * must have returned. + */ + if (!arg->old_exited_cs) { + arg->failed = 1; + printf("Error: preexisting reader should have exited by now!\n"); + } + + rcu_read_unlock(); + printf(")"); + + rcu_deregister_fibril(); + return 0; +} + +static bool dont_wait_for_new_reader(test_info_t *test_info) +{ + two_reader_info_t info = { 0 }; + + if (!create_fibril((fibril_func_t) preexisting_reader, &info)) + return false; + + if (!create_fibril((fibril_func_t) new_reader, &info)) + return false; + + /* Waits for the preexisting_reader to enter its CS.*/ + while (!info.old_entered_cs) { + async_usleep(WAIT_STEP_US); + } + + assert(!info.old_exited_cs); + assert(!info.new_entered_cs); + assert(!info.new_exited_cs); + + printf("sync["); + info.synching = true; + rcu_synchronize(); + printf(" ]"); + + /* Load info.exited_cs */ + memory_barrier(); + + if (!info.old_exited_cs) { + printf("Error: rcu_sync() returned before preexisting reader exited.\n"); + info.failed = 1; + } + + bool new_outside_cs = !info.new_entered_cs || info.new_exited_cs; + + /* Test if new reader is waiting in CS before setting synched. */ + compiler_barrier(); + info.synched = true; + + if (new_outside_cs) { + printf("Error: new reader CS held up rcu_sync(). (4)\n"); + info.failed = 1; + } else { + /* Wait for the new reader. */ + rcu_synchronize(); + + if (!info.new_exited_cs) { + printf("Error: 2nd rcu_sync() returned before new reader exited.\n"); + info.failed = 1; + } + + printf("\n"); + } + + if (info.failed) { + /* + * Sleep some more so we don't free info on stack while readers + * are using it. + */ + async_usleep(WAIT_STEP_US); + } + + return 0 == info.failed; +} + +#undef WAIT_STEP_US + +/*--------------------------------------------------------------------*/ +#define WAIT_STEP_US 500 * USECS_PER_MS + +typedef struct exit_reader_info { + bool entered_cs; + bool exited_cs; + bool synching; + bool synched; +} exit_reader_info_t; + + +static int exiting_locked_reader(exit_reader_info_t *arg) +{ + rcu_register_fibril(); + + printf("old-lock{"); + rcu_read_lock(); + rcu_read_lock(); + rcu_read_lock(); + arg->entered_cs = true; + + printf("wait-for-sync{"); + /* Wait for rcu_sync() to start waiting for us. */ + while (!arg->synching) { + async_usleep(WAIT_STEP_US); + } + printf(" }"); + + rcu_read_unlock(); + printf(" }"); + + arg->exited_cs = true; + /* Store exited_cs before unlocking reader section in deregister. */ + memory_barrier(); + + /* Deregister forcefully unlocks the reader section. */ + rcu_deregister_fibril(); + return 0; +} + + +static bool wait_for_exiting_reader(test_info_t *test_info) +{ + exit_reader_info_t info = { 0 }; + + if (!create_fibril((fibril_func_t) exiting_locked_reader, &info)) + return false; + + /* Waits for the preexisting_reader to enter its CS.*/ + while (!info.entered_cs) { + async_usleep(WAIT_STEP_US); + } + + assert(!info.exited_cs); + + printf("sync["); + info.synching = true; + rcu_synchronize(); + info.synched = true; + printf(" ]\n"); + + /* Load info.exited_cs */ + memory_barrier(); + + if (!info.exited_cs) { + printf("Error: rcu_deregister_fibril did not unlock the CS.\n"); + return false; + } + + return true; +} + +#undef WAIT_STEP_US + + +/*--------------------------------------------------------------------*/ + +typedef struct { + atomic_t time; + atomic_t max_start_time_of_done_sync; + + size_t total_workers; + size_t done_reader_cnt; + size_t done_updater_cnt; + fibril_mutex_t done_cnt_mtx; + fibril_condvar_t done_cnt_changed; + + size_t read_iters; + size_t upd_iters; + + atomic_t seed; + int failed; +} seq_test_info_t; + + +static void signal_seq_fibril_done(seq_test_info_t *arg, size_t *cnt) +{ + fibril_mutex_lock(&arg->done_cnt_mtx); + ++*cnt; + + if (arg->total_workers == arg->done_reader_cnt + arg->done_updater_cnt) { + fibril_condvar_signal(&arg->done_cnt_changed); + } + + fibril_mutex_unlock(&arg->done_cnt_mtx); +} + +static int seq_reader(seq_test_info_t *arg) +{ + rcu_register_fibril(); + + size_t seed = (size_t) atomic_preinc(&arg->seed); + bool first = (seed == 1); + + for (size_t k = 0; k < arg->read_iters; ++k) { + /* Print progress if the first reader fibril. */ + if (first && 0 == k % (arg->read_iters/100 + 1)) { + printf("."); + } + + rcu_read_lock(); + atomic_count_t start_time = atomic_preinc(&arg->time); + + /* Do some work. */ + seed = next_rand(seed); + size_t idle_iters = seed % 8; + + for (size_t i = 0; i < idle_iters; ++i) { + fibril_yield(); + } + + /* + * Check if the most recently started rcu_sync of the already + * finished rcu_syncs did not happen to start after this reader + * and, therefore, should have waited for this reader to exit + * (but did not - since it already announced it completed). + */ + if (start_time <= atomic_get(&arg->max_start_time_of_done_sync)) { + arg->failed = 1; + } + + rcu_read_unlock(); + } + + rcu_deregister_fibril(); + + signal_seq_fibril_done(arg, &arg->done_reader_cnt); + return 0; +} + +static int seq_updater(seq_test_info_t *arg) +{ + rcu_register_fibril(); + + for (size_t k = 0; k < arg->upd_iters; ++k) { + atomic_count_t start_time = atomic_get(&arg->time); + rcu_synchronize(); + + /* This is prone to a race but if it happens it errs to the safe side.*/ + if (atomic_get(&arg->max_start_time_of_done_sync) < start_time) { + atomic_set(&arg->max_start_time_of_done_sync, start_time); + } + } + + rcu_deregister_fibril(); + + signal_seq_fibril_done(arg, &arg->done_updater_cnt); + return 0; +} + +static bool seq_test(test_info_t *test_info) +{ + size_t reader_cnt = test_info->thread_cnt; + size_t updater_cnt = test_info->thread_cnt; + + seq_test_info_t info = { + .time = {0}, + .max_start_time_of_done_sync = {0}, + .read_iters = 10 * 1000, + .upd_iters = 5 * 1000, + .total_workers = updater_cnt + reader_cnt, + .done_reader_cnt = 0, + .done_updater_cnt = 0, + .done_cnt_mtx = FIBRIL_MUTEX_INITIALIZER(info.done_cnt_mtx), + .done_cnt_changed = FIBRIL_CONDVAR_INITIALIZER(info.done_cnt_changed), + .seed = {0}, + .failed = 0, + }; + + /* Create and start worker fibrils. */ + for (size_t k = 0; k + k < reader_cnt + updater_cnt; ++k) { + bool ok = create_fibril((fibril_func_t) seq_reader, &info); + ok = ok && create_fibril((fibril_func_t) seq_updater, &info); + + if (!ok) { + /* Let the already created fibrils corrupt the stack. */ + return false; + } + } + + /* Wait for all worker fibrils to complete their work. */ + fibril_mutex_lock(&info.done_cnt_mtx); + + while (info.total_workers != info.done_reader_cnt + info.done_updater_cnt) { + fibril_condvar_wait(&info.done_cnt_changed, &info.done_cnt_mtx); + } + + fibril_mutex_unlock(&info.done_cnt_mtx); + + if (info.failed) { + printf("Error: rcu_sync() did not wait for a preexisting reader."); + } + + return 0 == info.failed; +} + +/*--------------------------------------------------------------------*/ + +static FIBRIL_MUTEX_INITIALIZE(blocking_mtx); + +static void dummy_fibril(void *arg) +{ + /* Block on an already locked mutex - enters the fibril manager. */ + fibril_mutex_lock(&blocking_mtx); + assert(false); +} + +static bool create_threads(size_t cnt) +{ + /* Sanity check. */ + assert(cnt < 1024); + + /* Keep this mutex locked so that dummy fibrils never exit. */ + bool success = fibril_mutex_trylock(&blocking_mtx); + assert(success); + + for (size_t k = 0; k < cnt; ++k) { + thread_id_t tid; + + int ret = thread_create(dummy_fibril, NULL, "urcu-test-worker", &tid); + if (EOK != ret) { + printf("Failed to create thread '%zu' (error: %d)\n", k + 1, ret); + return false; + } + } + + return true; +} + +/*--------------------------------------------------------------------*/ +static test_desc_t *find_test(const char *name) +{ + /* First match for test name. */ + for (size_t k = 0; k < test_desc_cnt; ++k) { + test_desc_t *t = &test_desc[k]; + + if (t->func && 0 == str_cmp(t->name, name)) + return t; + } + + /* Try to match the test number. */ + uint32_t test_num = 0; + + if (EOK == str_uint32_t(name, NULL, 0, true, &test_num)) { + if (test_num < test_desc_cnt && test_desc[test_num].func) { + return &test_desc[test_num]; + } + } + + return NULL; +} + +static void list_tests(void) +{ + printf("Available tests: \n"); + + for (size_t i = 0; i < test_desc_cnt; ++i) { + test_desc_t *t = &test_desc[i]; + + if (!t->func) + continue; + + const char *type = ""; + + if (t->type == T_SANITY) + type = " (sanity)"; + if (t->type == T_STRESS) + type = " (stress)"; + + printf("%zu: %s ..%s %s\n", i, t->name, type, t->desc); + } +} + + +static void print_usage(void) +{ + printf("Usage: rcutest [test_name|test_number] {number_of_threads}\n"); + list_tests(); + + printf("\nExample usage:\n"); + printf("\trcutest *\n"); + printf("\trcutest sanity-tests\n"); +} + + +static bool parse_cmd_line(int argc, char **argv, test_info_t *info) +{ + if (argc != 2 && argc != 3) { + print_usage(); + return false; + } + + info->desc = find_test(argv[1]); + + if (!info->desc) { + printf("Non-existent test '%s'.\n", argv[1]); + list_tests(); + return false; + } + + if (argc == 3) { + uint32_t thread_cnt = 0; + int ret = str_uint32_t(argv[2], NULL, 0, true, &thread_cnt); + + if (ret == EOK && 1 <= thread_cnt && thread_cnt <= 64) { + info->thread_cnt = thread_cnt; + } else { + info->thread_cnt = 1; + printf("Err: Invalid number of threads '%s'; using 1.\n", argv[2]); + } + } else { + info->thread_cnt = 1; + } + + return true; +} + +int main(int argc, char **argv) +{ + rcu_register_fibril(); + + test_info_t info; + + bool ok = parse_cmd_line(argc, argv, &info); + ok = ok && create_threads(info.thread_cnt - 1); + + if (ok) { + assert(1 <= info.thread_cnt); + test_desc_t *t = info.desc; + + printf("Running '%s' (in %zu threads)...\n", t->name, info.thread_cnt); + ok = t->func(&info); + + printf("%s: '%s'\n", ok ? "Passed" : "FAILED", t->name); + + rcu_deregister_fibril(); + + /* Let the kernel clean up the created background threads. */ + return ok ? 0 : 1; + } else { + rcu_deregister_fibril(); + return 2; + } +} + + +/** + * @} + */