1a358f406STanner Love /* SPDX-License-Identifier: GPL-2.0 */ 2a358f406STanner Love #ifndef _LINUX_ONCE_LITE_H 3a358f406STanner Love #define _LINUX_ONCE_LITE_H 4a358f406STanner Love 5a358f406STanner Love #include <linux/types.h> 6a358f406STanner Love 7a358f406STanner Love /* Call a function once. Similar to DO_ONCE(), but does not use jump label 8a358f406STanner Love * patching via static keys. 9a358f406STanner Love */ 10a358f406STanner Love #define DO_ONCE_LITE(func, ...) \ 11a358f406STanner Love DO_ONCE_LITE_IF(true, func, ##__VA_ARGS__) 12*a1a5482aSPeter Zijlstra 13*a1a5482aSPeter Zijlstra #define __ONCE_LITE_IF(condition) \ 14a358f406STanner Love ({ \ 15a358f406STanner Love static bool __section(".data.once") __already_done; \ 16*a1a5482aSPeter Zijlstra bool __ret_cond = !!(condition); \ 17*a1a5482aSPeter Zijlstra bool __ret_once = false; \ 18*a1a5482aSPeter Zijlstra \ 19*a1a5482aSPeter Zijlstra if (unlikely(__ret_cond && !__already_done)) { \ 20*a1a5482aSPeter Zijlstra __already_done = true; \ 21*a1a5482aSPeter Zijlstra __ret_once = true; \ 22*a1a5482aSPeter Zijlstra } \ 23*a1a5482aSPeter Zijlstra unlikely(__ret_once); \ 24*a1a5482aSPeter Zijlstra }) 25*a1a5482aSPeter Zijlstra 26*a1a5482aSPeter Zijlstra #define DO_ONCE_LITE_IF(condition, func, ...) \ 27*a1a5482aSPeter Zijlstra ({ \ 28a358f406STanner Love bool __ret_do_once = !!(condition); \ 29a358f406STanner Love \ 30*a1a5482aSPeter Zijlstra if (__ONCE_LITE_IF(__ret_do_once)) \ 31a358f406STanner Love func(__VA_ARGS__); \ 32*a1a5482aSPeter Zijlstra \ 33a358f406STanner Love unlikely(__ret_do_once); \ 34a358f406STanner Love }) 35a358f406STanner Love 36a358f406STanner Love #endif /* _LINUX_ONCE_LITE_H */ 37