Message ID | 20221219164459.3614-1-andrea.cervesato@suse.com |
---|---|
State | Accepted |
Headers | show |
Series | [v1] Fix aio-stress stucking with multiple threads | expand |
Hello, Merged, thanks! Andrea Cervesato via ltp <ltp@lists.linux.it> writes: > CPUs that increment threads_starting and threads_ending might have not > flushed the operation into cache. This causes the test to stuck when > variables have not been increased correctly. To avoid this issue we > use pthread_barrier instead of flags. > Removed also no_stonewall flag that is useless for our testing. > > Signed-off-by: Andrea Cervesato <andrea.cervesato@suse.com> > --- > testcases/kernel/io/ltp-aiodio/aio-stress.c | 47 ++++----------------- > 1 file changed, 8 insertions(+), 39 deletions(-) > > diff --git a/testcases/kernel/io/ltp-aiodio/aio-stress.c b/testcases/kernel/io/ltp-aiodio/aio-stress.c > index 39db14d65..2fdbb84e8 100644 > --- a/testcases/kernel/io/ltp-aiodio/aio-stress.c > +++ b/testcases/kernel/io/ltp-aiodio/aio-stress.c > @@ -88,7 +88,6 @@ static int shm_id; > static char *unaligned_buffer; > static char *aligned_buffer; > static int padded_reclen; > -static char *no_stonewall; > static char *verify; > static char *verify_buf; > static char *unlink_files; > @@ -227,10 +226,7 @@ struct thread_info { > }; > > /* pthread mutexes and other globals for keeping the threads in sync */ > -static pthread_cond_t stage_cond = PTHREAD_COND_INITIALIZER; > -static pthread_mutex_t stage_mutex = PTHREAD_MUTEX_INITIALIZER; > -static int threads_ending; > -static int threads_starting; > +static pthread_barrier_t worker_barrier; > static struct timeval global_stage_start_time; > static struct thread_info *global_thread_info; > > @@ -1025,9 +1021,6 @@ static void global_thread_throughput(struct thread_info *t, char *this_stage) > if (total_mb) { > tst_res(TINFO, "%s throughput (%.2f MB/s)", this_stage, total_mb / runtime); > tst_res(TINFO, "%.2f MB in %.2fs", total_mb, runtime); > - > - if (no_stonewall) > - tst_res(TINFO, "min transfer %.2fMB", min_trans); > } > } > > @@ -1053,18 +1046,8 @@ static int *worker(struct thread_info *t) > > restart: > if (num_threads > 1) { > - pthread_mutex_lock(&stage_mutex); > - threads_starting++; > - > - if (threads_starting == num_threads) { > - threads_ending = 0; > + if (pthread_barrier_wait(&worker_barrier)) > gettimeofday(&global_stage_start_time, NULL); > - pthread_cond_broadcast(&stage_cond); > - } > - > - while (threads_starting != num_threads) > - pthread_cond_wait(&stage_cond, &stage_mutex); > - pthread_mutex_unlock(&stage_mutex); > } > > if (t->active_opers) { > @@ -1077,14 +1060,7 @@ restart: > > /* first we send everything through aio */ > while (t->active_opers && cnt < iterations) { > - if (!no_stonewall && threads_ending) { > - oper = t->active_opers; > - oper->stonewalled = 1; > - oper_list_del(oper, &t->active_opers); > - oper_list_add(oper, &t->finished_opers); > - } else { > - run_active_list(t, io_iter, max_io_submit); > - } > + run_active_list(t, io_iter, max_io_submit); > cnt++; > } > > @@ -1135,18 +1111,8 @@ restart: > } > > if (num_threads > 1) { > - pthread_mutex_lock(&stage_mutex); > - threads_ending++; > - > - if (threads_ending == num_threads) { > - threads_starting = 0; > - pthread_cond_broadcast(&stage_cond); > + if (pthread_barrier_wait(&worker_barrier)) > global_thread_throughput(t, this_stage); > - } > - > - while (threads_ending != num_threads) > - pthread_cond_wait(&stage_cond, &stage_mutex); > - pthread_mutex_unlock(&stage_mutex); > } > > /* someone got restarted, go back to the beginning */ > @@ -1177,6 +1143,8 @@ static int run_workers(struct thread_info *t, int num_threads) > int ret = 0; > int i; > > + pthread_barrier_init(&worker_barrier, NULL, num_threads); > + > for (i = 0; i < num_threads; i++) > SAFE_PTHREAD_CREATE(&t[i].tid, NULL, (start_routine)worker, t + i); > > @@ -1185,6 +1153,8 @@ static int run_workers(struct thread_info *t, int num_threads) > ret |= (intptr_t)retval; > } > > + pthread_barrier_destroy(&worker_barrier); > + > return ret; > } > > @@ -1397,7 +1367,6 @@ static struct tst_test test = { > { "t:", &str_num_threads, "Number of threads to run" }, > { "u", &unlink_files, "Unlink files after completion" }, > { "v", &verify, "Verification of bytes written" }, > - { "x", &no_stonewall, "Turn off thread stonewalling" }, > {}, > }, > }; > -- > 2.35.3
diff --git a/testcases/kernel/io/ltp-aiodio/aio-stress.c b/testcases/kernel/io/ltp-aiodio/aio-stress.c index 39db14d65..2fdbb84e8 100644 --- a/testcases/kernel/io/ltp-aiodio/aio-stress.c +++ b/testcases/kernel/io/ltp-aiodio/aio-stress.c @@ -88,7 +88,6 @@ static int shm_id; static char *unaligned_buffer; static char *aligned_buffer; static int padded_reclen; -static char *no_stonewall; static char *verify; static char *verify_buf; static char *unlink_files; @@ -227,10 +226,7 @@ struct thread_info { }; /* pthread mutexes and other globals for keeping the threads in sync */ -static pthread_cond_t stage_cond = PTHREAD_COND_INITIALIZER; -static pthread_mutex_t stage_mutex = PTHREAD_MUTEX_INITIALIZER; -static int threads_ending; -static int threads_starting; +static pthread_barrier_t worker_barrier; static struct timeval global_stage_start_time; static struct thread_info *global_thread_info; @@ -1025,9 +1021,6 @@ static void global_thread_throughput(struct thread_info *t, char *this_stage) if (total_mb) { tst_res(TINFO, "%s throughput (%.2f MB/s)", this_stage, total_mb / runtime); tst_res(TINFO, "%.2f MB in %.2fs", total_mb, runtime); - - if (no_stonewall) - tst_res(TINFO, "min transfer %.2fMB", min_trans); } } @@ -1053,18 +1046,8 @@ static int *worker(struct thread_info *t) restart: if (num_threads > 1) { - pthread_mutex_lock(&stage_mutex); - threads_starting++; - - if (threads_starting == num_threads) { - threads_ending = 0; + if (pthread_barrier_wait(&worker_barrier)) gettimeofday(&global_stage_start_time, NULL); - pthread_cond_broadcast(&stage_cond); - } - - while (threads_starting != num_threads) - pthread_cond_wait(&stage_cond, &stage_mutex); - pthread_mutex_unlock(&stage_mutex); } if (t->active_opers) { @@ -1077,14 +1060,7 @@ restart: /* first we send everything through aio */ while (t->active_opers && cnt < iterations) { - if (!no_stonewall && threads_ending) { - oper = t->active_opers; - oper->stonewalled = 1; - oper_list_del(oper, &t->active_opers); - oper_list_add(oper, &t->finished_opers); - } else { - run_active_list(t, io_iter, max_io_submit); - } + run_active_list(t, io_iter, max_io_submit); cnt++; } @@ -1135,18 +1111,8 @@ restart: } if (num_threads > 1) { - pthread_mutex_lock(&stage_mutex); - threads_ending++; - - if (threads_ending == num_threads) { - threads_starting = 0; - pthread_cond_broadcast(&stage_cond); + if (pthread_barrier_wait(&worker_barrier)) global_thread_throughput(t, this_stage); - } - - while (threads_ending != num_threads) - pthread_cond_wait(&stage_cond, &stage_mutex); - pthread_mutex_unlock(&stage_mutex); } /* someone got restarted, go back to the beginning */ @@ -1177,6 +1143,8 @@ static int run_workers(struct thread_info *t, int num_threads) int ret = 0; int i; + pthread_barrier_init(&worker_barrier, NULL, num_threads); + for (i = 0; i < num_threads; i++) SAFE_PTHREAD_CREATE(&t[i].tid, NULL, (start_routine)worker, t + i); @@ -1185,6 +1153,8 @@ static int run_workers(struct thread_info *t, int num_threads) ret |= (intptr_t)retval; } + pthread_barrier_destroy(&worker_barrier); + return ret; } @@ -1397,7 +1367,6 @@ static struct tst_test test = { { "t:", &str_num_threads, "Number of threads to run" }, { "u", &unlink_files, "Unlink files after completion" }, { "v", &verify, "Verification of bytes written" }, - { "x", &no_stonewall, "Turn off thread stonewalling" }, {}, }, };
CPUs that increment threads_starting and threads_ending might have not flushed the operation into cache. This causes the test to stuck when variables have not been increased correctly. To avoid this issue we use pthread_barrier instead of flags. Removed also no_stonewall flag that is useless for our testing. Signed-off-by: Andrea Cervesato <andrea.cervesato@suse.com> --- testcases/kernel/io/ltp-aiodio/aio-stress.c | 47 ++++----------------- 1 file changed, 8 insertions(+), 39 deletions(-)