1 /* SPDX-License-Identifier: BSD-3-Clause
2 * Copyright(c) 2019 Intel Corporation
3 */
4
5 #ifndef _RTE_STACK_LF_H_
6 #define _RTE_STACK_LF_H_
7
8 #if !(defined(RTE_ARCH_X86_64) || defined(RTE_ARCH_ARM64))
9 #include "rte_stack_lf_stubs.h"
10 #else
11 #ifdef RTE_USE_C11_MEM_MODEL
12 #include "rte_stack_lf_c11.h"
13 #else
14 #include "rte_stack_lf_generic.h"
15 #endif
16 #endif
17
18 /**
19 * @internal Push several objects on the lock-free stack (MT-safe).
20 *
21 * @param s
22 * A pointer to the stack structure.
23 * @param obj_table
24 * A pointer to a table of void * pointers (objects).
25 * @param n
26 * The number of objects to push on the stack from the obj_table.
27 * @return
28 * Actual number of objects enqueued.
29 */
30 static __rte_always_inline unsigned int
__rte_stack_lf_push(struct rte_stack * s,void * const * obj_table,unsigned int n)31 __rte_stack_lf_push(struct rte_stack *s,
32 void * const *obj_table,
33 unsigned int n)
34 {
35 struct rte_stack_lf_elem *tmp, *first, *last = NULL;
36 unsigned int i;
37
38 if (unlikely(n == 0))
39 return 0;
40
41 /* Pop n free elements */
42 first = __rte_stack_lf_pop_elems(&s->stack_lf.free, n, NULL, &last);
43 if (unlikely(first == NULL))
44 return 0;
45
46 /* Construct the list elements */
47 for (tmp = first, i = 0; i < n; i++, tmp = tmp->next)
48 tmp->data = obj_table[n - i - 1];
49
50 /* Push them to the used list */
51 __rte_stack_lf_push_elems(&s->stack_lf.used, first, last, n);
52
53 return n;
54 }
55
56 /**
57 * @internal Pop several objects from the lock-free stack (MT-safe).
58 *
59 * @param s
60 * A pointer to the stack structure.
61 * @param obj_table
62 * A pointer to a table of void * pointers (objects).
63 * @param n
64 * The number of objects to pull from the stack.
65 * @return
66 * - Actual number of objects popped.
67 */
68 static __rte_always_inline unsigned int
__rte_stack_lf_pop(struct rte_stack * s,void ** obj_table,unsigned int n)69 __rte_stack_lf_pop(struct rte_stack *s, void **obj_table, unsigned int n)
70 {
71 struct rte_stack_lf_elem *first, *last = NULL;
72
73 if (unlikely(n == 0))
74 return 0;
75
76 /* Pop n used elements */
77 first = __rte_stack_lf_pop_elems(&s->stack_lf.used,
78 n, obj_table, &last);
79 if (unlikely(first == NULL))
80 return 0;
81
82 /* Push the list elements to the free list */
83 __rte_stack_lf_push_elems(&s->stack_lf.free, first, last, n);
84
85 return n;
86 }
87
88 /**
89 * @internal Initialize a lock-free stack.
90 *
91 * @param s
92 * A pointer to the stack structure.
93 * @param count
94 * The size of the stack.
95 */
96 void
97 rte_stack_lf_init(struct rte_stack *s, unsigned int count);
98
99 /**
100 * @internal Return the memory required for a lock-free stack.
101 *
102 * @param count
103 * The size of the stack.
104 * @return
105 * The bytes to allocate for a lock-free stack.
106 */
107 ssize_t
108 rte_stack_lf_get_memsize(unsigned int count);
109
110 #endif /* _RTE_STACK_LF_H_ */
111