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-rw-r--r--kernel/fork.c119
1 files changed, 81 insertions, 38 deletions
diff --git a/kernel/fork.c b/kernel/fork.c
index 49adc0e8d47..1c999f3e0b4 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -11,7 +11,6 @@
* management can be a bitch. See 'mm/memory.c': 'copy_page_range()'
*/
-#include <linux/config.h>
#include <linux/slab.h>
#include <linux/init.h>
#include <linux/unistd.h>
@@ -44,6 +43,9 @@
#include <linux/rmap.h>
#include <linux/acct.h>
#include <linux/cn_proc.h>
+#include <linux/delayacct.h>
+#include <linux/taskstats_kern.h>
+#include <linux/random.h>
#include <asm/pgtable.h>
#include <asm/pgalloc.h>
@@ -62,9 +64,7 @@ int max_threads; /* tunable limit on nr_threads */
DEFINE_PER_CPU(unsigned long, process_counts) = 0;
- __cacheline_aligned DEFINE_RWLOCK(tasklist_lock); /* outer */
-
-EXPORT_SYMBOL(tasklist_lock);
+__cacheline_aligned DEFINE_RWLOCK(tasklist_lock); /* outer */
int nr_processes(void)
{
@@ -104,6 +104,7 @@ static kmem_cache_t *mm_cachep;
void free_task(struct task_struct *tsk)
{
free_thread_info(tsk->thread_info);
+ rt_mutex_debug_task_free(tsk);
free_task_struct(tsk);
}
EXPORT_SYMBOL(free_task);
@@ -117,6 +118,7 @@ void __put_task_struct(struct task_struct *tsk)
security_task_free(tsk);
free_uid(tsk->user);
put_group_info(tsk->group_info);
+ delayacct_tsk_free(tsk);
if (!profile_handoff_task(tsk))
free_task(tsk);
@@ -174,10 +176,16 @@ static struct task_struct *dup_task_struct(struct task_struct *orig)
tsk->thread_info = ti;
setup_thread_stack(tsk, orig);
+#ifdef CONFIG_CC_STACKPROTECTOR
+ tsk->stack_canary = get_random_int();
+#endif
+
/* One for us, one for whoever does the "release_task()" (usually parent) */
atomic_set(&tsk->usage,2);
atomic_set(&tsk->fs_excl, 0);
+#ifdef CONFIG_BLK_DEV_IO_TRACE
tsk->btrace_seq = 0;
+#endif
tsk->splice_pipe = NULL;
return tsk;
}
@@ -193,7 +201,10 @@ static inline int dup_mmap(struct mm_struct *mm, struct mm_struct *oldmm)
down_write(&oldmm->mmap_sem);
flush_cache_mm(oldmm);
- down_write(&mm->mmap_sem);
+ /*
+ * Not linked in yet - no deadlock potential:
+ */
+ down_write_nested(&mm->mmap_sem, SINGLE_DEPTH_NESTING);
mm->locked_vm = 0;
mm->mmap = NULL;
@@ -817,6 +828,7 @@ static inline int copy_signal(unsigned long clone_flags, struct task_struct * ts
if (clone_flags & CLONE_THREAD) {
atomic_inc(&current->signal->count);
atomic_inc(&current->signal->live);
+ taskstats_tgid_alloc(current->signal);
return 0;
}
sig = kmem_cache_alloc(signal_cachep, GFP_KERNEL);
@@ -861,6 +873,7 @@ static inline int copy_signal(unsigned long clone_flags, struct task_struct * ts
INIT_LIST_HEAD(&sig->cpu_timers[0]);
INIT_LIST_HEAD(&sig->cpu_timers[1]);
INIT_LIST_HEAD(&sig->cpu_timers[2]);
+ taskstats_tgid_init(sig);
task_lock(current->group_leader);
memcpy(sig->rlim, current->signal->rlim, sizeof sig->rlim);
@@ -874,6 +887,7 @@ static inline int copy_signal(unsigned long clone_flags, struct task_struct * ts
tsk->it_prof_expires =
secs_to_cputime(sig->rlim[RLIMIT_CPU].rlim_cur);
}
+ acct_init_pacct(&sig->pacct);
return 0;
}
@@ -881,6 +895,7 @@ static inline int copy_signal(unsigned long clone_flags, struct task_struct * ts
void __cleanup_signal(struct signal_struct *sig)
{
exit_thread_group_keys(sig);
+ taskstats_tgid_free(sig);
kmem_cache_free(signal_cachep, sig);
}
@@ -912,6 +927,15 @@ asmlinkage long sys_set_tid_address(int __user *tidptr)
return current->pid;
}
+static inline void rt_mutex_init_task(struct task_struct *p)
+{
+#ifdef CONFIG_RT_MUTEXES
+ spin_lock_init(&p->pi_lock);
+ plist_head_init(&p->pi_waiters, &p->pi_lock);
+ p->pi_blocked_on = NULL;
+#endif
+}
+
/*
* This creates a new process as a copy of the old one,
* but does not actually start it yet.
@@ -920,13 +944,13 @@ asmlinkage long sys_set_tid_address(int __user *tidptr)
* parts of the process environment (as per the clone
* flags). The actual kick-off is left to the caller.
*/
-static task_t *copy_process(unsigned long clone_flags,
- unsigned long stack_start,
- struct pt_regs *regs,
- unsigned long stack_size,
- int __user *parent_tidptr,
- int __user *child_tidptr,
- int pid)
+static struct task_struct *copy_process(unsigned long clone_flags,
+ unsigned long stack_start,
+ struct pt_regs *regs,
+ unsigned long stack_size,
+ int __user *parent_tidptr,
+ int __user *child_tidptr,
+ int pid)
{
int retval;
struct task_struct *p = NULL;
@@ -958,6 +982,10 @@ static task_t *copy_process(unsigned long clone_flags,
if (!p)
goto fork_out;
+#ifdef CONFIG_TRACE_IRQFLAGS
+ DEBUG_LOCKS_WARN_ON(!p->hardirqs_enabled);
+ DEBUG_LOCKS_WARN_ON(!p->softirqs_enabled);
+#endif
retval = -EAGAIN;
if (atomic_read(&p->user->processes) >=
p->signal->rlim[RLIMIT_NPROC].rlim_cur) {
@@ -985,20 +1013,18 @@ static task_t *copy_process(unsigned long clone_flags,
goto bad_fork_cleanup_put_domain;
p->did_exec = 0;
+ delayacct_tsk_init(p); /* Must remain after dup_task_struct() */
copy_flags(clone_flags, p);
p->pid = pid;
retval = -EFAULT;
if (clone_flags & CLONE_PARENT_SETTID)
if (put_user(p->pid, parent_tidptr))
- goto bad_fork_cleanup;
-
- p->proc_dentry = NULL;
+ goto bad_fork_cleanup_delays_binfmt;
INIT_LIST_HEAD(&p->children);
INIT_LIST_HEAD(&p->sibling);
p->vfork_done = NULL;
spin_lock_init(&p->alloc_lock);
- spin_lock_init(&p->proc_lock);
clear_tsk_thread_flag(p, TIF_SIGPENDING);
init_sigpending(&p->pending);
@@ -1035,6 +1061,32 @@ static task_t *copy_process(unsigned long clone_flags,
}
mpol_fix_fork_child_flag(p);
#endif
+#ifdef CONFIG_TRACE_IRQFLAGS
+ p->irq_events = 0;
+#ifdef __ARCH_WANT_INTERRUPTS_ON_CTXSW
+ p->hardirqs_enabled = 1;
+#else
+ p->hardirqs_enabled = 0;
+#endif
+ p->hardirq_enable_ip = 0;
+ p->hardirq_enable_event = 0;
+ p->hardirq_disable_ip = _THIS_IP_;
+ p->hardirq_disable_event = 0;
+ p->softirqs_enabled = 1;
+ p->softirq_enable_ip = _THIS_IP_;
+ p->softirq_enable_event = 0;
+ p->softirq_disable_ip = 0;
+ p->softirq_disable_event = 0;
+ p->hardirq_context = 0;
+ p->softirq_context = 0;
+#endif
+#ifdef CONFIG_LOCKDEP
+ p->lockdep_depth = 0; /* no locks held yet */
+ p->curr_chain_key = 0;
+ p->lockdep_recursion = 0;
+#endif
+
+ rt_mutex_init_task(p);
#ifdef CONFIG_DEBUG_MUTEXES
p->blocked_on = NULL; /* not blocked yet */
@@ -1078,6 +1130,9 @@ static task_t *copy_process(unsigned long clone_flags,
#ifdef CONFIG_COMPAT
p->compat_robust_list = NULL;
#endif
+ INIT_LIST_HEAD(&p->pi_state_list);
+ p->pi_state_cache = NULL;
+
/*
* sigaltstack should be cleared when sharing the same VM
*/
@@ -1095,7 +1150,6 @@ static task_t *copy_process(unsigned long clone_flags,
/* Our parent execution domain becomes current domain
These must match for thread signalling to apply */
-
p->parent_exec_id = p->self_exec_id;
/* ok, now we should be set up.. */
@@ -1118,6 +1172,9 @@ static task_t *copy_process(unsigned long clone_flags,
/* Need tasklist lock for parent etc handling! */
write_lock_irq(&tasklist_lock);
+ /* for sys_ioprio_set(IOPRIO_WHO_PGRP) */
+ p->ioprio = current->ioprio;
+
/*
* The task hasn't been attached yet, so its cpus_allowed mask will
* not be changed, nor will its assigned CPU.
@@ -1158,18 +1215,6 @@ static task_t *copy_process(unsigned long clone_flags,
}
if (clone_flags & CLONE_THREAD) {
- /*
- * Important: if an exit-all has been started then
- * do not create this new thread - the whole thread
- * group is supposed to exit anyway.
- */
- if (current->signal->flags & SIGNAL_GROUP_EXIT) {
- spin_unlock(&current->sighand->siglock);
- write_unlock_irq(&tasklist_lock);
- retval = -EAGAIN;
- goto bad_fork_cleanup_namespace;
- }
-
p->group_leader = current->group_leader;
list_add_tail_rcu(&p->thread_group, &p->group_leader->thread_group);
@@ -1189,11 +1234,6 @@ static task_t *copy_process(unsigned long clone_flags,
}
}
- /*
- * inherit ioprio
- */
- p->ioprio = current->ioprio;
-
if (likely(p->pid)) {
add_parent(p);
if (unlikely(p->ptrace & PT_PTRACED))
@@ -1246,7 +1286,8 @@ bad_fork_cleanup_policy:
bad_fork_cleanup_cpuset:
#endif
cpuset_exit(p);
-bad_fork_cleanup:
+bad_fork_cleanup_delays_binfmt:
+ delayacct_tsk_free(p);
if (p->binfmt)
module_put(p->binfmt->module);
bad_fork_cleanup_put_domain:
@@ -1267,9 +1308,9 @@ struct pt_regs * __devinit __attribute__((weak)) idle_regs(struct pt_regs *regs)
return regs;
}
-task_t * __devinit fork_idle(int cpu)
+struct task_struct * __devinit fork_idle(int cpu)
{
- task_t *task;
+ struct task_struct *task;
struct pt_regs regs;
task = copy_process(CLONE_VM, 0, idle_regs(&regs), 0, NULL, NULL, 0);
@@ -1356,8 +1397,10 @@ long do_fork(unsigned long clone_flags,
if (clone_flags & CLONE_VFORK) {
wait_for_completion(&vfork);
- if (unlikely (current->ptrace & PT_TRACE_VFORK_DONE))
+ if (unlikely (current->ptrace & PT_TRACE_VFORK_DONE)) {
+ current->ptrace_message = nr;
ptrace_notify ((PTRACE_EVENT_VFORK_DONE << 8) | SIGTRAP);
+ }
}
} else {
free_pid(pid);
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2025-03-29 02:25:32 +0000