diff options
Diffstat (limited to 'arch/arm/include/asm/current.h')
| -rw-r--r-- | arch/arm/include/asm/current.h | 52 |
1 files changed, 31 insertions, 21 deletions
diff --git a/arch/arm/include/asm/current.h b/arch/arm/include/asm/current.h index 6bf0aad672c3..5225cb1c803b 100644 --- a/arch/arm/include/asm/current.h +++ b/arch/arm/include/asm/current.h @@ -8,47 +8,57 @@ #define _ASM_ARM_CURRENT_H #ifndef __ASSEMBLY__ +#include <asm/insn.h> struct task_struct; -static inline void set_current(struct task_struct *cur) -{ - if (!IS_ENABLED(CONFIG_CURRENT_POINTER_IN_TPIDRURO)) - return; - - /* Set TPIDRURO */ - asm("mcr p15, 0, %0, c13, c0, 3" :: "r"(cur) : "memory"); -} - -#ifdef CONFIG_CURRENT_POINTER_IN_TPIDRURO +extern struct task_struct *__current; -static inline struct task_struct *get_current(void) +static __always_inline __attribute_const__ struct task_struct *get_current(void) { struct task_struct *cur; -#if __has_builtin(__builtin_thread_pointer) && \ - !(defined(CONFIG_THUMB2_KERNEL) && \ - defined(CONFIG_CC_IS_CLANG) && CONFIG_CLANG_VERSION < 130001) +#if __has_builtin(__builtin_thread_pointer) && defined(CONFIG_CURRENT_POINTER_IN_TPIDRURO) /* * Use the __builtin helper when available - this results in better * code, especially when using GCC in combination with the per-task * stack protector, as the compiler will recognize that it needs to * load the TLS register only once in every function. - * - * Clang < 13.0.1 gets this wrong for Thumb2 builds: - * https://github.com/ClangBuiltLinux/linux/issues/1485 */ cur = __builtin_thread_pointer(); +#elif defined(CONFIG_CURRENT_POINTER_IN_TPIDRURO) || defined(CONFIG_SMP) + asm("0: mrc p15, 0, %0, c13, c0, 3 \n\t" +#ifdef CONFIG_CPU_V6 + "1: \n\t" + " .subsection 1 \n\t" +#if defined(CONFIG_ARM_HAS_GROUP_RELOCS) && \ + !(defined(MODULE) && defined(CONFIG_ARM_MODULE_PLTS)) + "2: " LOAD_SYM_ARMV6(%0, __current) " \n\t" + " b 1b \n\t" #else - asm("mrc p15, 0, %0, c13, c0, 3" : "=r"(cur)); + "2: ldr %0, 3f \n\t" + " ldr %0, [%0] \n\t" + " b 1b \n\t" + "3: .long __current \n\t" +#endif + " .previous \n\t" + " .pushsection \".alt.smp.init\", \"a\" \n\t" + " .long 0b - . \n\t" + " b . + (2b - 0b) \n\t" + " .popsection \n\t" +#endif + : "=r"(cur)); +#elif __LINUX_ARM_ARCH__>= 7 || \ + !defined(CONFIG_ARM_HAS_GROUP_RELOCS) || \ + (defined(MODULE) && defined(CONFIG_ARM_MODULE_PLTS)) + cur = __current; +#else + asm(LOAD_SYM_ARMV6(%0, __current) : "=r"(cur)); #endif return cur; } #define current get_current() -#else -#include <asm-generic/current.h> -#endif /* CONFIG_CURRENT_POINTER_IN_TPIDRURO */ #endif /* __ASSEMBLY__ */ |