X-Git-Url: http://ftp.safe.ca/?p=safe%2Fjmp%2Flinux-2.6;a=blobdiff_plain;f=kernel%2Ffork.c;h=4d57d9e3a6e992a9d0a3514138008a0d8aefaeff;hp=166b8c49257c589750f0b67479011ba7bac97038;hb=4434ade8c9334a3ab975d8993de456f06841899e;hpb=1d510750941a53a1d3049c1d33c75d6dfcd78618 diff --git a/kernel/fork.c b/kernel/fork.c index 166b8c4..4d57d9e 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -64,6 +64,7 @@ #include #include #include +#include #include #include @@ -86,6 +87,14 @@ DEFINE_PER_CPU(unsigned long, process_counts) = 0; __cacheline_aligned DEFINE_RWLOCK(tasklist_lock); /* outer */ +#ifdef CONFIG_PROVE_RCU +int lockdep_tasklist_lock_is_held(void) +{ + return lockdep_is_held(&tasklist_lock); +} +EXPORT_SYMBOL_GPL(lockdep_tasklist_lock_is_held); +#endif /* #ifdef CONFIG_PROVE_RCU */ + int nr_processes(void) { int cpu; @@ -249,6 +258,7 @@ static struct task_struct *dup_task_struct(struct task_struct *orig) goto out; setup_thread_stack(tsk, orig); + clear_user_return_notifier(tsk); stackend = end_of_stack(tsk); *stackend = STACK_END_MAGIC; /* for overflow detection */ @@ -326,15 +336,17 @@ static int dup_mmap(struct mm_struct *mm, struct mm_struct *oldmm) if (!tmp) goto fail_nomem; *tmp = *mpnt; + INIT_LIST_HEAD(&tmp->anon_vma_chain); pol = mpol_dup(vma_policy(mpnt)); retval = PTR_ERR(pol); if (IS_ERR(pol)) goto fail_nomem_policy; vma_set_policy(tmp, pol); + if (anon_vma_fork(tmp, mpnt)) + goto fail_nomem_anon_vma_fork; tmp->vm_flags &= ~VM_LOCKED; tmp->vm_mm = mm; tmp->vm_next = NULL; - anon_vma_link(tmp); file = tmp->vm_file; if (file) { struct inode *inode = file->f_path.dentry->d_inode; @@ -389,6 +401,8 @@ out: flush_tlb_mm(oldmm); up_write(&oldmm->mmap_sem); return retval; +fail_nomem_anon_vma_fork: + mpol_put(pol); fail_nomem_policy: kmem_cache_free(vm_area_cachep, tmp); fail_nomem: @@ -452,8 +466,7 @@ static struct mm_struct * mm_init(struct mm_struct * mm, struct task_struct *p) (current->mm->flags & MMF_INIT_MASK) : default_dump_filter; mm->core_state = NULL; mm->nr_ptes = 0; - set_mm_counter(mm, file_rss, 0); - set_mm_counter(mm, anon_rss, 0); + memset(&mm->rss_stat, 0, sizeof(mm->rss_stat)); spin_lock_init(&mm->page_table_lock); mm->free_area_cache = TASK_UNMAPPED_BASE; mm->cached_hole_size = ~0UL; @@ -822,23 +835,14 @@ void __cleanup_sighand(struct sighand_struct *sighand) */ static void posix_cpu_timers_init_group(struct signal_struct *sig) { + unsigned long cpu_limit; + /* Thread group counters. */ thread_group_cputime_init(sig); - /* Expiration times and increments. */ - sig->it[CPUCLOCK_PROF].expires = cputime_zero; - sig->it[CPUCLOCK_PROF].incr = cputime_zero; - sig->it[CPUCLOCK_VIRT].expires = cputime_zero; - sig->it[CPUCLOCK_VIRT].incr = cputime_zero; - - /* Cached expiration times. */ - sig->cputime_expires.prof_exp = cputime_zero; - sig->cputime_expires.virt_exp = cputime_zero; - sig->cputime_expires.sched_exp = 0; - - if (sig->rlim[RLIMIT_CPU].rlim_cur != RLIM_INFINITY) { - sig->cputime_expires.prof_exp = - secs_to_cputime(sig->rlim[RLIMIT_CPU].rlim_cur); + cpu_limit = ACCESS_ONCE(sig->rlim[RLIMIT_CPU].rlim_cur); + if (cpu_limit != RLIM_INFINITY) { + sig->cputime_expires.prof_exp = secs_to_cputime(cpu_limit); sig->cputimer.running = 1; } @@ -855,7 +859,7 @@ static int copy_signal(unsigned long clone_flags, struct task_struct *tsk) if (clone_flags & CLONE_THREAD) return 0; - sig = kmem_cache_alloc(signal_cachep, GFP_KERNEL); + sig = kmem_cache_zalloc(signal_cachep, GFP_KERNEL); tsk->signal = sig; if (!sig) return -ENOMEM; @@ -863,43 +867,21 @@ static int copy_signal(unsigned long clone_flags, struct task_struct *tsk) atomic_set(&sig->count, 1); atomic_set(&sig->live, 1); init_waitqueue_head(&sig->wait_chldexit); - sig->flags = 0; if (clone_flags & CLONE_NEWPID) sig->flags |= SIGNAL_UNKILLABLE; - sig->group_exit_code = 0; - sig->group_exit_task = NULL; - sig->group_stop_count = 0; sig->curr_target = tsk; init_sigpending(&sig->shared_pending); INIT_LIST_HEAD(&sig->posix_timers); hrtimer_init(&sig->real_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); - sig->it_real_incr.tv64 = 0; sig->real_timer.function = it_real_fn; - sig->leader = 0; /* session leadership doesn't inherit */ - sig->tty_old_pgrp = NULL; - sig->tty = NULL; - - sig->utime = sig->stime = sig->cutime = sig->cstime = cputime_zero; - sig->gtime = cputime_zero; - sig->cgtime = cputime_zero; - sig->nvcsw = sig->nivcsw = sig->cnvcsw = sig->cnivcsw = 0; - sig->min_flt = sig->maj_flt = sig->cmin_flt = sig->cmaj_flt = 0; - sig->inblock = sig->oublock = sig->cinblock = sig->coublock = 0; - sig->maxrss = sig->cmaxrss = 0; - task_io_accounting_init(&sig->ioac); - sig->sum_sched_runtime = 0; - taskstats_tgid_init(sig); - task_lock(current->group_leader); memcpy(sig->rlim, current->signal->rlim, sizeof sig->rlim); task_unlock(current->group_leader); posix_cpu_timers_init_group(sig); - acct_init_pacct(&sig->pacct); - tty_audit_fork(sig); sig->oom_adj = current->signal->oom_adj; @@ -934,9 +916,9 @@ SYSCALL_DEFINE1(set_tid_address, int __user *, tidptr) static void rt_mutex_init_task(struct task_struct *p) { - spin_lock_init(&p->pi_lock); + raw_spin_lock_init(&p->pi_lock); #ifdef CONFIG_RT_MUTEXES - plist_head_init(&p->pi_waiters, &p->pi_lock); + plist_head_init_raw(&p->pi_waiters, &p->pi_lock); p->pi_blocked_on = NULL; #endif } @@ -1028,7 +1010,7 @@ static struct task_struct *copy_process(unsigned long clone_flags, #endif retval = -EAGAIN; if (atomic_read(&p->real_cred->user->processes) >= - p->signal->rlim[RLIMIT_NPROC].rlim_cur) { + task_rlimit(p, RLIMIT_NPROC)) { if (!capable(CAP_SYS_ADMIN) && !capable(CAP_SYS_RESOURCE) && p->real_cred->user != INIT_USER) goto bad_fork_free; @@ -1066,8 +1048,13 @@ static struct task_struct *copy_process(unsigned long clone_flags, p->gtime = cputime_zero; p->utimescaled = cputime_zero; p->stimescaled = cputime_zero; +#ifndef CONFIG_VIRT_CPU_ACCOUNTING p->prev_utime = cputime_zero; p->prev_stime = cputime_zero; +#endif +#if defined(SPLIT_RSS_COUNTING) + memset(&p->rss_stat, 0, sizeof(p->rss_stat)); +#endif p->default_timer_slack_ns = current->timer_slack_ns; @@ -1120,10 +1107,10 @@ static struct task_struct *copy_process(unsigned long clone_flags, #ifdef CONFIG_DEBUG_MUTEXES p->blocked_on = NULL; /* not blocked yet */ #endif - - p->bts = NULL; - - p->stack_start = stack_start; +#ifdef CONFIG_CGROUP_MEM_RES_CTLR + p->memcg_batch.do_batch = 0; + p->memcg_batch.memcg = NULL; +#endif /* Perform scheduler related setup. Assign this task to a CPU. */ sched_fork(p, clone_flags); @@ -1199,9 +1186,10 @@ static struct task_struct *copy_process(unsigned long clone_flags, p->sas_ss_sp = p->sas_ss_size = 0; /* - * Syscall tracing should be turned off in the child regardless - * of CLONE_PTRACE. + * Syscall tracing and stepping should be turned off in the + * child regardless of CLONE_PTRACE. */ + user_disable_single_step(p); clear_tsk_thread_flag(p, TIF_SYSCALL_TRACE); #ifdef TIF_SYSCALL_EMU clear_tsk_thread_flag(p, TIF_SYSCALL_EMU); @@ -1229,21 +1217,6 @@ static struct task_struct *copy_process(unsigned long clone_flags, /* Need tasklist lock for parent etc handling! */ write_lock_irq(&tasklist_lock); - /* - * The task hasn't been attached yet, so its cpus_allowed mask will - * not be changed, nor will its assigned CPU. - * - * The cpus_allowed mask of the parent may have changed after it was - * copied first time - so re-copy it here, then check the child's CPU - * to ensure it is on a valid CPU (and if not, just force it back to - * parent's CPU). This avoids alot of nasty races. - */ - p->cpus_allowed = current->cpus_allowed; - p->rt.nr_cpus_allowed = current->rt.nr_cpus_allowed; - if (unlikely(!cpu_isset(task_cpu(p), p->cpus_allowed) || - !cpu_online(task_cpu(p)))) - set_task_cpu(p, smp_processor_id()); - /* CLONE_PARENT re-uses the old parent */ if (clone_flags & (CLONE_PARENT|CLONE_THREAD)) { p->real_parent = current->real_parent; @@ -1279,7 +1252,6 @@ static struct task_struct *copy_process(unsigned long clone_flags, } if (likely(p->pid)) { - list_add_tail(&p->sibling, &p->real_parent->children); tracehook_finish_clone(p, clone_flags, trace); if (thread_group_leader(p)) { @@ -1291,6 +1263,7 @@ static struct task_struct *copy_process(unsigned long clone_flags, p->signal->tty = tty_kref_get(current->signal->tty); attach_pid(p, PIDTYPE_PGID, task_pgrp(current)); attach_pid(p, PIDTYPE_SID, task_session(current)); + list_add_tail(&p->sibling, &p->real_parent->children); list_add_tail_rcu(&p->tasks, &init_task.tasks); __get_cpu_var(process_counts)++; } @@ -1310,7 +1283,8 @@ bad_fork_free_pid: if (pid != &init_struct_pid) free_pid(pid); bad_fork_cleanup_io: - put_io_context(p->io_context); + if (p->io_context) + exit_io_context(p); bad_fork_cleanup_namespaces: exit_task_namespaces(p); bad_fork_cleanup_mm: