1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _LINUX_ONCE_LITE_H
3 #define _LINUX_ONCE_LITE_H
4
5 #include <linux/types.h>
6
7 /* Call a function once. Similar to DO_ONCE(), but does not use jump label
8 * patching via static keys.
9 */
10 #define DO_ONCE_LITE(func, ...) \
11 DO_ONCE_LITE_IF(true, func, ##__VA_ARGS__)
12
13 #define __ONCE_LITE_IF(condition) \
14 ({ \
15 static bool __section(".data.once") __already_done; \
16 bool __ret_cond = !!(condition); \
17 bool __ret_once = false; \
18 \
19 if (unlikely(__ret_cond && !__already_done)) { \
20 __already_done = true; \
21 __ret_once = true; \
22 } \
23 unlikely(__ret_once); \
24 })
25
26 #define DO_ONCE_LITE_IF(condition, func, ...) \
27 ({ \
28 bool __ret_do_once = !!(condition); \
29 \
30 if (__ONCE_LITE_IF(__ret_do_once)) \
31 func(__VA_ARGS__); \
32 \
33 unlikely(__ret_do_once); \
34 })
35
36 #endif /* _LINUX_ONCE_LITE_H */
37
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