mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-23 17:30:02 +00:00
![Qinglang Miao](/assets/img/avatar_default.png)
Use DEFINE_SHOW_ATTRIBUTE macro to simplify the code. As inode->iprivate equals to third parameter of debugfs_create_file() which is NULL. So it's equivalent to original code logic. Signed-off-by: Qinglang Miao <miaoqinglang@huawei.com> Signed-off-by: Coly Li <colyli@suse.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
207 lines
4.5 KiB
C
207 lines
4.5 KiB
C
// SPDX-License-Identifier: GPL-2.0
|
|
/*
|
|
* Asynchronous refcounty things
|
|
*
|
|
* Copyright 2010, 2011 Kent Overstreet <kent.overstreet@gmail.com>
|
|
* Copyright 2012 Google, Inc.
|
|
*/
|
|
|
|
#include <linux/debugfs.h>
|
|
#include <linux/module.h>
|
|
#include <linux/seq_file.h>
|
|
#include <linux/sched/debug.h>
|
|
|
|
#include "closure.h"
|
|
|
|
static inline void closure_put_after_sub(struct closure *cl, int flags)
|
|
{
|
|
int r = flags & CLOSURE_REMAINING_MASK;
|
|
|
|
BUG_ON(flags & CLOSURE_GUARD_MASK);
|
|
BUG_ON(!r && (flags & ~CLOSURE_DESTRUCTOR));
|
|
|
|
if (!r) {
|
|
if (cl->fn && !(flags & CLOSURE_DESTRUCTOR)) {
|
|
atomic_set(&cl->remaining,
|
|
CLOSURE_REMAINING_INITIALIZER);
|
|
closure_queue(cl);
|
|
} else {
|
|
struct closure *parent = cl->parent;
|
|
closure_fn *destructor = cl->fn;
|
|
|
|
closure_debug_destroy(cl);
|
|
|
|
if (destructor)
|
|
destructor(cl);
|
|
|
|
if (parent)
|
|
closure_put(parent);
|
|
}
|
|
}
|
|
}
|
|
|
|
/* For clearing flags with the same atomic op as a put */
|
|
void closure_sub(struct closure *cl, int v)
|
|
{
|
|
closure_put_after_sub(cl, atomic_sub_return(v, &cl->remaining));
|
|
}
|
|
|
|
/*
|
|
* closure_put - decrement a closure's refcount
|
|
*/
|
|
void closure_put(struct closure *cl)
|
|
{
|
|
closure_put_after_sub(cl, atomic_dec_return(&cl->remaining));
|
|
}
|
|
|
|
/*
|
|
* closure_wake_up - wake up all closures on a wait list, without memory barrier
|
|
*/
|
|
void __closure_wake_up(struct closure_waitlist *wait_list)
|
|
{
|
|
struct llist_node *list;
|
|
struct closure *cl, *t;
|
|
struct llist_node *reverse = NULL;
|
|
|
|
list = llist_del_all(&wait_list->list);
|
|
|
|
/* We first reverse the list to preserve FIFO ordering and fairness */
|
|
reverse = llist_reverse_order(list);
|
|
|
|
/* Then do the wakeups */
|
|
llist_for_each_entry_safe(cl, t, reverse, list) {
|
|
closure_set_waiting(cl, 0);
|
|
closure_sub(cl, CLOSURE_WAITING + 1);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* closure_wait - add a closure to a waitlist
|
|
* @waitlist: will own a ref on @cl, which will be released when
|
|
* closure_wake_up() is called on @waitlist.
|
|
* @cl: closure pointer.
|
|
*
|
|
*/
|
|
bool closure_wait(struct closure_waitlist *waitlist, struct closure *cl)
|
|
{
|
|
if (atomic_read(&cl->remaining) & CLOSURE_WAITING)
|
|
return false;
|
|
|
|
closure_set_waiting(cl, _RET_IP_);
|
|
atomic_add(CLOSURE_WAITING + 1, &cl->remaining);
|
|
llist_add(&cl->list, &waitlist->list);
|
|
|
|
return true;
|
|
}
|
|
|
|
struct closure_syncer {
|
|
struct task_struct *task;
|
|
int done;
|
|
};
|
|
|
|
static void closure_sync_fn(struct closure *cl)
|
|
{
|
|
struct closure_syncer *s = cl->s;
|
|
struct task_struct *p;
|
|
|
|
rcu_read_lock();
|
|
p = READ_ONCE(s->task);
|
|
s->done = 1;
|
|
wake_up_process(p);
|
|
rcu_read_unlock();
|
|
}
|
|
|
|
void __sched __closure_sync(struct closure *cl)
|
|
{
|
|
struct closure_syncer s = { .task = current };
|
|
|
|
cl->s = &s;
|
|
continue_at(cl, closure_sync_fn, NULL);
|
|
|
|
while (1) {
|
|
set_current_state(TASK_UNINTERRUPTIBLE);
|
|
if (s.done)
|
|
break;
|
|
schedule();
|
|
}
|
|
|
|
__set_current_state(TASK_RUNNING);
|
|
}
|
|
|
|
#ifdef CONFIG_BCACHE_CLOSURES_DEBUG
|
|
|
|
static LIST_HEAD(closure_list);
|
|
static DEFINE_SPINLOCK(closure_list_lock);
|
|
|
|
void closure_debug_create(struct closure *cl)
|
|
{
|
|
unsigned long flags;
|
|
|
|
BUG_ON(cl->magic == CLOSURE_MAGIC_ALIVE);
|
|
cl->magic = CLOSURE_MAGIC_ALIVE;
|
|
|
|
spin_lock_irqsave(&closure_list_lock, flags);
|
|
list_add(&cl->all, &closure_list);
|
|
spin_unlock_irqrestore(&closure_list_lock, flags);
|
|
}
|
|
|
|
void closure_debug_destroy(struct closure *cl)
|
|
{
|
|
unsigned long flags;
|
|
|
|
BUG_ON(cl->magic != CLOSURE_MAGIC_ALIVE);
|
|
cl->magic = CLOSURE_MAGIC_DEAD;
|
|
|
|
spin_lock_irqsave(&closure_list_lock, flags);
|
|
list_del(&cl->all);
|
|
spin_unlock_irqrestore(&closure_list_lock, flags);
|
|
}
|
|
|
|
static struct dentry *closure_debug;
|
|
|
|
static int debug_show(struct seq_file *f, void *data)
|
|
{
|
|
struct closure *cl;
|
|
|
|
spin_lock_irq(&closure_list_lock);
|
|
|
|
list_for_each_entry(cl, &closure_list, all) {
|
|
int r = atomic_read(&cl->remaining);
|
|
|
|
seq_printf(f, "%p: %pS -> %pS p %p r %i ",
|
|
cl, (void *) cl->ip, cl->fn, cl->parent,
|
|
r & CLOSURE_REMAINING_MASK);
|
|
|
|
seq_printf(f, "%s%s\n",
|
|
test_bit(WORK_STRUCT_PENDING_BIT,
|
|
work_data_bits(&cl->work)) ? "Q" : "",
|
|
r & CLOSURE_RUNNING ? "R" : "");
|
|
|
|
if (r & CLOSURE_WAITING)
|
|
seq_printf(f, " W %pS\n",
|
|
(void *) cl->waiting_on);
|
|
|
|
seq_printf(f, "\n");
|
|
}
|
|
|
|
spin_unlock_irq(&closure_list_lock);
|
|
return 0;
|
|
}
|
|
|
|
DEFINE_SHOW_ATTRIBUTE(debug);
|
|
|
|
void __init closure_debug_init(void)
|
|
{
|
|
if (!IS_ERR_OR_NULL(bcache_debug))
|
|
/*
|
|
* it is unnecessary to check return value of
|
|
* debugfs_create_file(), we should not care
|
|
* about this.
|
|
*/
|
|
closure_debug = debugfs_create_file(
|
|
"closures", 0400, bcache_debug, NULL, &debug_fops);
|
|
}
|
|
#endif
|
|
|
|
MODULE_AUTHOR("Kent Overstreet <koverstreet@google.com>");
|
|
MODULE_LICENSE("GPL");
|