1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef __LINUX_SMP_TYPES_H
3#define __LINUX_SMP_TYPES_H
4
5#include <linux/llist.h>
6
7enum {
8	CSD_FLAG_LOCK		= 0x01,
9
10	IRQ_WORK_PENDING	= 0x01,
11	IRQ_WORK_BUSY		= 0x02,
12	IRQ_WORK_LAZY		= 0x04, /* No IPI, wait for tick */
13	IRQ_WORK_HARD_IRQ	= 0x08, /* IRQ context on PREEMPT_RT */
14
15	IRQ_WORK_CLAIMED	= (IRQ_WORK_PENDING | IRQ_WORK_BUSY),
16
17	CSD_TYPE_ASYNC		= 0x00,
18	CSD_TYPE_SYNC		= 0x10,
19	CSD_TYPE_IRQ_WORK	= 0x20,
20	CSD_TYPE_TTWU		= 0x30,
21
22	CSD_FLAG_TYPE_MASK	= 0xF0,
23};
24
25/*
26 * struct __call_single_node is the primary type on
27 * smp.c:call_single_queue.
28 *
29 * flush_smp_call_function_queue() only reads the type from
30 * __call_single_node::u_flags as a regular load, the above
31 * (anonymous) enum defines all the bits of this word.
32 *
33 * Other bits are not modified until the type is known.
34 *
35 * CSD_TYPE_SYNC/ASYNC:
36 *	struct {
37 *		struct llist_node node;
38 *		unsigned int flags;
39 *		smp_call_func_t func;
40 *		void *info;
41 *	};
42 *
43 * CSD_TYPE_IRQ_WORK:
44 *	struct {
45 *		struct llist_node node;
46 *		atomic_t flags;
47 *		void (*func)(struct irq_work *);
48 *	};
49 *
50 * CSD_TYPE_TTWU:
51 *	struct {
52 *		struct llist_node node;
53 *		unsigned int flags;
54 *	};
55 *
56 */
57
58struct __call_single_node {
59	struct llist_node	llist;
60	union {
61		unsigned int	u_flags;
62		atomic_t	a_flags;
63	};
64#ifdef CONFIG_64BIT
65	u16 src, dst;
66#endif
67};
68
69#endif /* __LINUX_SMP_TYPES_H */
70