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-rw-r--r--kernel/exit.c64
1 files changed, 38 insertions, 26 deletions
diff --git a/kernel/exit.c b/kernel/exit.c
index 1639564..30fcdf1 100644
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -40,13 +40,13 @@
#include <linux/cn_proc.h>
#include <linux/mutex.h>
#include <linux/futex.h>
-#include <linux/compat.h>
#include <linux/pipe_fs_i.h>
#include <linux/audit.h> /* for audit_free() */
#include <linux/resource.h>
#include <linux/blkdev.h>
#include <linux/task_io_accounting_ops.h>
#include <linux/tracehook.h>
+#include <trace/sched.h>
#include <asm/uaccess.h>
#include <asm/unistd.h>
@@ -112,8 +112,6 @@ static void __exit_signal(struct task_struct *tsk)
* We won't ever get here for the group leader, since it
* will have been the last reference on the signal_struct.
*/
- sig->utime = cputime_add(sig->utime, task_utime(tsk));
- sig->stime = cputime_add(sig->stime, task_stime(tsk));
sig->gtime = cputime_add(sig->gtime, task_gtime(tsk));
sig->min_flt += tsk->min_flt;
sig->maj_flt += tsk->maj_flt;
@@ -122,7 +120,6 @@ static void __exit_signal(struct task_struct *tsk)
sig->inblock += task_io_get_inblock(tsk);
sig->oublock += task_io_get_oublock(tsk);
task_io_accounting_add(&sig->ioac, &tsk->ioac);
- sig->sum_sched_runtime += tsk->se.sum_exec_runtime;
sig = NULL; /* Marker for below. */
}
@@ -143,13 +140,21 @@ static void __exit_signal(struct task_struct *tsk)
if (sig) {
flush_sigqueue(&sig->shared_pending);
taskstats_tgid_free(sig);
+ /*
+ * Make sure ->signal can't go away under rq->lock,
+ * see account_group_exec_runtime().
+ */
+ task_rq_unlock_wait(tsk);
__cleanup_signal(sig);
}
}
static void delayed_put_task_struct(struct rcu_head *rhp)
{
- put_task_struct(container_of(rhp, struct task_struct, rcu));
+ struct task_struct *tsk = container_of(rhp, struct task_struct, rcu);
+
+ trace_sched_process_free(tsk);
+ put_task_struct(tsk);
}
@@ -583,8 +588,6 @@ mm_need_new_owner(struct mm_struct *mm, struct task_struct *p)
* If there are other users of the mm and the owner (us) is exiting
* we need to find a new owner to take on the responsibility.
*/
- if (!mm)
- return 0;
if (atomic_read(&mm->mm_users) <= 1)
return 0;
if (mm->owner != p)
@@ -627,29 +630,38 @@ retry:
} while_each_thread(g, c);
read_unlock(&tasklist_lock);
+ /*
+ * We found no owner yet mm_users > 1: this implies that we are
+ * most likely racing with swapoff (try_to_unuse()) or /proc or
+ * ptrace or page migration (get_task_mm()). Mark owner as NULL,
+ * so that subsystems can understand the callback and take action.
+ */
+ down_write(&mm->mmap_sem);
+ cgroup_mm_owner_callbacks(mm->owner, NULL);
+ mm->owner = NULL;
+ up_write(&mm->mmap_sem);
return;
assign_new_owner:
BUG_ON(c == p);
get_task_struct(c);
+ read_unlock(&tasklist_lock);
+ down_write(&mm->mmap_sem);
/*
* The task_lock protects c->mm from changing.
* We always want mm->owner->mm == mm
*/
task_lock(c);
- /*
- * Delay read_unlock() till we have the task_lock()
- * to ensure that c does not slip away underneath us
- */
- read_unlock(&tasklist_lock);
if (c->mm != mm) {
task_unlock(c);
+ up_write(&mm->mmap_sem);
put_task_struct(c);
goto retry;
}
cgroup_mm_owner_callbacks(mm->owner, c);
mm->owner = c;
task_unlock(c);
+ up_write(&mm->mmap_sem);
put_task_struct(c);
}
#endif /* CONFIG_MM_OWNER */
@@ -1046,14 +1058,6 @@ NORET_TYPE void do_exit(long code)
exit_itimers(tsk->signal);
}
acct_collect(code, group_dead);
-#ifdef CONFIG_FUTEX
- if (unlikely(tsk->robust_list))
- exit_robust_list(tsk);
-#ifdef CONFIG_COMPAT
- if (unlikely(tsk->compat_robust_list))
- compat_exit_robust_list(tsk);
-#endif
-#endif
if (group_dead)
tty_audit_exit();
if (unlikely(tsk->audit_context))
@@ -1066,6 +1070,8 @@ NORET_TYPE void do_exit(long code)
if (group_dead)
acct_process();
+ trace_sched_process_exit(tsk);
+
exit_sem(tsk);
exit_files(tsk);
exit_fs(tsk);
@@ -1294,6 +1300,7 @@ static int wait_task_zombie(struct task_struct *p, int options,
if (likely(!traced)) {
struct signal_struct *psig;
struct signal_struct *sig;
+ struct task_cputime cputime;
/*
* The resource counters for the group leader are in its
@@ -1309,20 +1316,23 @@ static int wait_task_zombie(struct task_struct *p, int options,
* need to protect the access to p->parent->signal fields,
* as other threads in the parent group can be right
* here reaping other children at the same time.
+ *
+ * We use thread_group_cputime() to get times for the thread
+ * group, which consolidates times for all threads in the
+ * group including the group leader.
*/
+ thread_group_cputime(p, &cputime);
spin_lock_irq(&p->parent->sighand->siglock);
psig = p->parent->signal;
sig = p->signal;
psig->cutime =
cputime_add(psig->cutime,
- cputime_add(p->utime,
- cputime_add(sig->utime,
- sig->cutime)));
+ cputime_add(cputime.utime,
+ sig->cutime));
psig->cstime =
cputime_add(psig->cstime,
- cputime_add(p->stime,
- cputime_add(sig->stime,
- sig->cstime)));
+ cputime_add(cputime.stime,
+ sig->cstime));
psig->cgtime =
cputime_add(psig->cgtime,
cputime_add(p->gtime,
@@ -1667,6 +1677,8 @@ static long do_wait(enum pid_type type, struct pid *pid, int options,
struct task_struct *tsk;
int retval;
+ trace_sched_process_wait(pid);
+
add_wait_queue(&current->signal->wait_chldexit,&wait);
repeat:
/*
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