diff options
| -rw-r--r-- | arch/arm64/include/asm/cpufeature.h | 14 | ||||
| -rw-r--r-- | arch/arm64/kernel/cpufeature.c | 3 | ||||
| -rw-r--r-- | arch/arm64/kernel/smp.c | 5 |
3 files changed, 19 insertions, 3 deletions
diff --git a/arch/arm64/include/asm/cpufeature.h b/arch/arm64/include/asm/cpufeature.h index c07c5d1cd04a..23a76dc5a6cf 100644 --- a/arch/arm64/include/asm/cpufeature.h +++ b/arch/arm64/include/asm/cpufeature.h @@ -9,6 +9,8 @@ #ifndef __ASM_CPUFEATURE_H #define __ASM_CPUFEATURE_H +#include <linux/jump_label.h> + #include <asm/hwcap.h> #include <asm/sysreg.h> @@ -110,6 +112,7 @@ struct arm64_cpu_capabilities { }; extern DECLARE_BITMAP(cpu_hwcaps, ARM64_NCAPS); +extern struct static_key_false cpu_hwcap_keys[ARM64_NCAPS]; bool this_cpu_has_cap(unsigned int cap); @@ -122,16 +125,21 @@ static inline bool cpus_have_cap(unsigned int num) { if (num >= ARM64_NCAPS) return false; - return test_bit(num, cpu_hwcaps); + if (__builtin_constant_p(num)) + return static_branch_unlikely(&cpu_hwcap_keys[num]); + else + return test_bit(num, cpu_hwcaps); } static inline void cpus_set_cap(unsigned int num) { - if (num >= ARM64_NCAPS) + if (num >= ARM64_NCAPS) { pr_warn("Attempt to set an illegal CPU capability (%d >= %d)\n", num, ARM64_NCAPS); - else + } else { __set_bit(num, cpu_hwcaps); + static_branch_enable(&cpu_hwcap_keys[num]); + } } static inline int __attribute_const__ diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c index c3d7ae48f92d..9128ced913e7 100644 --- a/arch/arm64/kernel/cpufeature.c +++ b/arch/arm64/kernel/cpufeature.c @@ -46,6 +46,9 @@ unsigned int compat_elf_hwcap2 __read_mostly; DECLARE_BITMAP(cpu_hwcaps, ARM64_NCAPS); +DEFINE_STATIC_KEY_ARRAY_FALSE(cpu_hwcap_keys, ARM64_NCAPS); +EXPORT_SYMBOL(cpu_hwcap_keys); + #define __ARM64_FTR_BITS(SIGNED, STRICT, TYPE, SHIFT, WIDTH, SAFE_VAL) \ { \ .sign = SIGNED, \ diff --git a/arch/arm64/kernel/smp.c b/arch/arm64/kernel/smp.c index d93d43352504..c3c08368a685 100644 --- a/arch/arm64/kernel/smp.c +++ b/arch/arm64/kernel/smp.c @@ -437,6 +437,11 @@ void __init smp_cpus_done(unsigned int max_cpus) void __init smp_prepare_boot_cpu(void) { set_my_cpu_offset(per_cpu_offset(smp_processor_id())); + /* + * Initialise the static keys early as they may be enabled by the + * cpufeature code. + */ + jump_label_init(); cpuinfo_store_boot_cpu(); save_boot_cpu_run_el(); } |