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Diffstat (limited to 'kernel')
-rw-r--r--kernel/audit_tree.c10
-rw-r--r--kernel/audit_watch.c25
-rw-r--r--kernel/cgroup.c6
-rw-r--r--kernel/exit.c6
-rw-r--r--kernel/fork.c2
-rw-r--r--kernel/irq/manage.c6
-rw-r--r--kernel/signal.c15
-rw-r--r--kernel/task_work.c94
8 files changed, 77 insertions, 87 deletions
diff --git a/kernel/audit_tree.c b/kernel/audit_tree.c
index 5bf0790497e7..3a5ca582ba1e 100644
--- a/kernel/audit_tree.c
+++ b/kernel/audit_tree.c
@@ -595,7 +595,7 @@ void audit_trim_trees(void)
root_mnt = collect_mounts(&path);
path_put(&path);
- if (!root_mnt)
+ if (IS_ERR(root_mnt))
goto skip_it;
spin_lock(&hash_lock);
@@ -669,8 +669,8 @@ int audit_add_tree_rule(struct audit_krule *rule)
goto Err;
mnt = collect_mounts(&path);
path_put(&path);
- if (!mnt) {
- err = -ENOMEM;
+ if (IS_ERR(mnt)) {
+ err = PTR_ERR(mnt);
goto Err;
}
@@ -719,8 +719,8 @@ int audit_tag_tree(char *old, char *new)
return err;
tagged = collect_mounts(&path2);
path_put(&path2);
- if (!tagged)
- return -ENOMEM;
+ if (IS_ERR(tagged))
+ return PTR_ERR(tagged);
err = kern_path(old, 0, &path1);
if (err) {
diff --git a/kernel/audit_watch.c b/kernel/audit_watch.c
index e683869365d9..3823281401b5 100644
--- a/kernel/audit_watch.c
+++ b/kernel/audit_watch.c
@@ -355,34 +355,15 @@ static void audit_remove_parent_watches(struct audit_parent *parent)
/* Get path information necessary for adding watches. */
static int audit_get_nd(struct audit_watch *watch, struct path *parent)
{
- struct nameidata nd;
- struct dentry *d;
- int err;
-
- err = kern_path_parent(watch->path, &nd);
- if (err)
- return err;
-
- if (nd.last_type != LAST_NORM) {
- path_put(&nd.path);
- return -EINVAL;
- }
-
- mutex_lock_nested(&nd.path.dentry->d_inode->i_mutex, I_MUTEX_PARENT);
- d = lookup_one_len(nd.last.name, nd.path.dentry, nd.last.len);
- if (IS_ERR(d)) {
- mutex_unlock(&nd.path.dentry->d_inode->i_mutex);
- path_put(&nd.path);
+ struct dentry *d = kern_path_locked(watch->path, parent);
+ if (IS_ERR(d))
return PTR_ERR(d);
- }
+ mutex_unlock(&parent->dentry->d_inode->i_mutex);
if (d->d_inode) {
/* update watch filter fields */
watch->dev = d->d_inode->i_sb->s_dev;
watch->ino = d->d_inode->i_ino;
}
- mutex_unlock(&nd.path.dentry->d_inode->i_mutex);
-
- *parent = nd.path;
dput(d);
return 0;
}
diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index b303dfc7dce0..af2b5641fc8b 100644
--- a/kernel/cgroup.c
+++ b/kernel/cgroup.c
@@ -822,7 +822,7 @@ EXPORT_SYMBOL_GPL(cgroup_unlock);
*/
static int cgroup_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode);
-static struct dentry *cgroup_lookup(struct inode *, struct dentry *, struct nameidata *);
+static struct dentry *cgroup_lookup(struct inode *, struct dentry *, unsigned int);
static int cgroup_rmdir(struct inode *unused_dir, struct dentry *dentry);
static int cgroup_populate_dir(struct cgroup *cgrp);
static const struct inode_operations cgroup_dir_inode_operations;
@@ -1587,7 +1587,7 @@ static struct dentry *cgroup_mount(struct file_system_type *fs_type,
opts.new_root = new_root;
/* Locate an existing or new sb for this hierarchy */
- sb = sget(fs_type, cgroup_test_super, cgroup_set_super, &opts);
+ sb = sget(fs_type, cgroup_test_super, cgroup_set_super, 0, &opts);
if (IS_ERR(sb)) {
ret = PTR_ERR(sb);
cgroup_drop_root(opts.new_root);
@@ -2570,7 +2570,7 @@ static const struct inode_operations cgroup_dir_inode_operations = {
.rename = cgroup_rename,
};
-static struct dentry *cgroup_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd)
+static struct dentry *cgroup_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags)
{
if (dentry->d_name.len > NAME_MAX)
return ERR_PTR(-ENAMETOOLONG);
diff --git a/kernel/exit.c b/kernel/exit.c
index 2f59cc334516..d17f6c4ddfa9 100644
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -953,14 +953,11 @@ void do_exit(long code)
exit_signals(tsk); /* sets PF_EXITING */
/*
* tsk->flags are checked in the futex code to protect against
- * an exiting task cleaning up the robust pi futexes, and in
- * task_work_add() to avoid the race with exit_task_work().
+ * an exiting task cleaning up the robust pi futexes.
*/
smp_mb();
raw_spin_unlock_wait(&tsk->pi_lock);
- exit_task_work(tsk);
-
if (unlikely(in_atomic()))
printk(KERN_INFO "note: %s[%d] exited with preempt_count %d\n",
current->comm, task_pid_nr(current),
@@ -995,6 +992,7 @@ void do_exit(long code)
exit_shm(tsk);
exit_files(tsk);
exit_fs(tsk);
+ exit_task_work(tsk);
check_stack_usage();
exit_thread();
diff --git a/kernel/fork.c b/kernel/fork.c
index f00e319d8376..ff1cad3b7bdc 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -1420,7 +1420,7 @@ static struct task_struct *copy_process(unsigned long clone_flags,
*/
p->group_leader = p;
INIT_LIST_HEAD(&p->thread_group);
- INIT_HLIST_HEAD(&p->task_works);
+ p->task_works = NULL;
/* Now that the task is set up, run cgroup callbacks if
* necessary. We need to run them before the task is visible
diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c
index 8c548232ba39..814c9ef6bba1 100644
--- a/kernel/irq/manage.c
+++ b/kernel/irq/manage.c
@@ -781,7 +781,7 @@ static void wake_threads_waitq(struct irq_desc *desc)
wake_up(&desc->wait_for_threads);
}
-static void irq_thread_dtor(struct task_work *unused)
+static void irq_thread_dtor(struct callback_head *unused)
{
struct task_struct *tsk = current;
struct irq_desc *desc;
@@ -813,7 +813,7 @@ static void irq_thread_dtor(struct task_work *unused)
*/
static int irq_thread(void *data)
{
- struct task_work on_exit_work;
+ struct callback_head on_exit_work;
static const struct sched_param param = {
.sched_priority = MAX_USER_RT_PRIO/2,
};
@@ -830,7 +830,7 @@ static int irq_thread(void *data)
sched_setscheduler(current, SCHED_FIFO, &param);
- init_task_work(&on_exit_work, irq_thread_dtor, NULL);
+ init_task_work(&on_exit_work, irq_thread_dtor);
task_work_add(current, &on_exit_work, false);
while (!irq_wait_for_interrupt(action)) {
diff --git a/kernel/signal.c b/kernel/signal.c
index 677102789cf2..be4f856d52f8 100644
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -1971,6 +1971,13 @@ static void ptrace_do_notify(int signr, int exit_code, int why)
void ptrace_notify(int exit_code)
{
BUG_ON((exit_code & (0x7f | ~0xffff)) != SIGTRAP);
+ if (unlikely(current->task_works)) {
+ if (test_and_clear_ti_thread_flag(current_thread_info(),
+ TIF_NOTIFY_RESUME)) {
+ smp_mb__after_clear_bit();
+ task_work_run();
+ }
+ }
spin_lock_irq(&current->sighand->siglock);
ptrace_do_notify(SIGTRAP, exit_code, CLD_TRAPPED);
@@ -2191,6 +2198,14 @@ int get_signal_to_deliver(siginfo_t *info, struct k_sigaction *return_ka,
struct signal_struct *signal = current->signal;
int signr;
+ if (unlikely(current->task_works)) {
+ if (test_and_clear_ti_thread_flag(current_thread_info(),
+ TIF_NOTIFY_RESUME)) {
+ smp_mb__after_clear_bit();
+ task_work_run();
+ }
+ }
+
if (unlikely(uprobe_deny_signal()))
return 0;
diff --git a/kernel/task_work.c b/kernel/task_work.c
index 82d1c794066d..91d4e1742a0c 100644
--- a/kernel/task_work.c
+++ b/kernel/task_work.c
@@ -3,82 +3,78 @@
#include <linux/tracehook.h>
int
-task_work_add(struct task_struct *task, struct task_work *twork, bool notify)
+task_work_add(struct task_struct *task, struct callback_head *twork, bool notify)
{
+ struct callback_head *last, *first;
unsigned long flags;
- int err = -ESRCH;
-#ifndef TIF_NOTIFY_RESUME
- if (notify)
- return -ENOTSUPP;
-#endif
/*
- * We must not insert the new work if the task has already passed
- * exit_task_work(). We rely on do_exit()->raw_spin_unlock_wait()
- * and check PF_EXITING under pi_lock.
+ * Not inserting the new work if the task has already passed
+ * exit_task_work() is the responisbility of callers.
*/
raw_spin_lock_irqsave(&task->pi_lock, flags);
- if (likely(!(task->flags & PF_EXITING))) {
- hlist_add_head(&twork->hlist, &task->task_works);
- err = 0;
- }
+ last = task->task_works;
+ first = last ? last->next : twork;
+ twork->next = first;
+ if (last)
+ last->next = twork;
+ task->task_works = twork;
raw_spin_unlock_irqrestore(&task->pi_lock, flags);
/* test_and_set_bit() implies mb(), see tracehook_notify_resume(). */
- if (likely(!err) && notify)
+ if (notify)
set_notify_resume(task);
- return err;
+ return 0;
}
-struct task_work *
+struct callback_head *
task_work_cancel(struct task_struct *task, task_work_func_t func)
{
unsigned long flags;
- struct task_work *twork;
- struct hlist_node *pos;
+ struct callback_head *last, *res = NULL;
raw_spin_lock_irqsave(&task->pi_lock, flags);
- hlist_for_each_entry(twork, pos, &task->task_works, hlist) {
- if (twork->func == func) {
- hlist_del(&twork->hlist);
- goto found;
+ last = task->task_works;
+ if (last) {
+ struct callback_head *q = last, *p = q->next;
+ while (1) {
+ if (p->func == func) {
+ q->next = p->next;
+ if (p == last)
+ task->task_works = q == p ? NULL : q;
+ res = p;
+ break;
+ }
+ if (p == last)
+ break;
+ q = p;
+ p = q->next;
}
}
- twork = NULL;
- found:
raw_spin_unlock_irqrestore(&task->pi_lock, flags);
-
- return twork;
+ return res;
}
void task_work_run(void)
{
struct task_struct *task = current;
- struct hlist_head task_works;
- struct hlist_node *pos;
+ struct callback_head *p, *q;
- raw_spin_lock_irq(&task->pi_lock);
- hlist_move_list(&task->task_works, &task_works);
- raw_spin_unlock_irq(&task->pi_lock);
+ while (1) {
+ raw_spin_lock_irq(&task->pi_lock);
+ p = task->task_works;
+ task->task_works = NULL;
+ raw_spin_unlock_irq(&task->pi_lock);
- if (unlikely(hlist_empty(&task_works)))
- return;
- /*
- * We use hlist to save the space in task_struct, but we want fifo.
- * Find the last entry, the list should be short, then process them
- * in reverse order.
- */
- for (pos = task_works.first; pos->next; pos = pos->next)
- ;
+ if (unlikely(!p))
+ return;
- for (;;) {
- struct hlist_node **pprev = pos->pprev;
- struct task_work *twork = container_of(pos, struct task_work,
- hlist);
- twork->func(twork);
-
- if (pprev == &task_works.first)
- break;
- pos = container_of(pprev, struct hlist_node, next);
+ q = p->next; /* head */
+ p->next = NULL; /* cut it */
+ while (q) {
+ p = q->next;
+ q->func(q);
+ q = p;
+ }
}
}