From d7982dd0ab2a1a315b5f9859c67a02414ce6274f Mon Sep 17 00:00:00 2001 From: Jan Kara Date: Tue, 24 May 2016 17:03:21 +0200 Subject: [PATCH] fio: Simplify forking of processes There is no reason to re-attach to shared memory segments after fork(2). shmat(2) manpage specifically says: After a fork(2), the child inherits the attached shared memory segments. So get rid of some unnecessary code. Signed-off-by: Jan Kara Signed-off-by: Jens Axboe --- backend.c | 46 +++++++--------------------------------------- 1 file changed, 7 insertions(+), 39 deletions(-) diff --git a/backend.c b/backend.c index f132222d..ce23c696 100644 --- a/backend.c +++ b/backend.c @@ -1794,39 +1794,6 @@ err: return (void *) (uintptr_t) td->error; } - -/* - * We cannot pass the td data into a forked process, so attach the td and - * pass it to the thread worker. - */ -static int fork_main(struct sk_out *sk_out, int shmid, int offset) -{ - struct fork_data *fd; - void *data, *ret; - -#if !defined(__hpux) && !defined(CONFIG_NO_SHM) - data = shmat(shmid, NULL, 0); - if (data == (void *) -1) { - int __err = errno; - - perror("shmat"); - return __err; - } -#else - /* - * HP-UX inherits shm mappings? - */ - data = threads; -#endif - - fd = calloc(1, sizeof(*fd)); - fd->td = data + offset * sizeof(struct thread_data); - fd->sk_out = sk_out; - ret = thread_main(fd); - shmdt(data); - return (int) (uintptr_t) ret; -} - static void dump_td_info(struct thread_data *td) { log_err("fio: job '%s' (state=%d) hasn't exited in %lu seconds, it " @@ -2164,6 +2131,7 @@ reap: struct thread_data *map[REAL_MAX_JOBS]; struct timeval this_start; int this_jobs = 0, left; + struct fork_data *fd; /* * create threads (TD_NOT_CREATED -> TD_CREATED) @@ -2213,14 +2181,13 @@ reap: map[this_jobs++] = td; nr_started++; + fd = calloc(1, sizeof(*fd)); + fd->td = td; + fd->sk_out = sk_out; + if (td->o.use_thread) { - struct fork_data *fd; int ret; - fd = calloc(1, sizeof(*fd)); - fd->td = td; - fd->sk_out = sk_out; - dprint(FD_PROCESS, "will pthread_create\n"); ret = pthread_create(&td->thread, NULL, thread_main, fd); @@ -2240,8 +2207,9 @@ reap: dprint(FD_PROCESS, "will fork\n"); pid = fork(); if (!pid) { - int ret = fork_main(sk_out, shm_id, i); + int ret; + ret = (int)(uintptr_t)thread_main(fd); _exit(ret); } else if (i == fio_debug_jobno) *fio_debug_jobp = pid; -- 2.25.1