diff options
Diffstat (limited to 'arch/arm64/include/asm/vdso/gettimeofday.h')
| -rw-r--r-- | arch/arm64/include/asm/vdso/gettimeofday.h | 49 |
1 files changed, 32 insertions, 17 deletions
diff --git a/arch/arm64/include/asm/vdso/gettimeofday.h b/arch/arm64/include/asm/vdso/gettimeofday.h index b08f476b72b4..764d13e2916c 100644 --- a/arch/arm64/include/asm/vdso/gettimeofday.h +++ b/arch/arm64/include/asm/vdso/gettimeofday.h @@ -7,10 +7,10 @@ #ifndef __ASSEMBLY__ +#include <asm/alternative.h> +#include <asm/barrier.h> #include <asm/unistd.h> -#include <uapi/linux/time.h> - -#define __VDSO_USE_SYSCALL ULLONG_MAX +#include <asm/sysreg.h> #define VDSO_HAS_CLOCK_GETRES 1 @@ -66,28 +66,35 @@ int clock_getres_fallback(clockid_t _clkid, struct __kernel_timespec *_ts) return ret; } -static __always_inline u64 __arch_get_hw_counter(s32 clock_mode) +static __always_inline u64 __arch_get_hw_counter(s32 clock_mode, + const struct vdso_data *vd) { u64 res; /* - * clock_mode == 0 implies that vDSO are enabled otherwise - * fallback on syscall. + * Core checks for mode already, so this raced against a concurrent + * update. Return something. Core will do another round and then + * see the mode change and fallback to the syscall. */ - if (clock_mode) - return __VDSO_USE_SYSCALL; + if (clock_mode == VDSO_CLOCKMODE_NONE) + return 0; /* - * This isb() is required to prevent that the counter value + * If FEAT_ECV is available, use the self-synchronizing counter. + * Otherwise the isb is required to prevent that the counter value * is speculated. - */ - isb(); - asm volatile("mrs %0, cntvct_el0" : "=r" (res) :: "memory"); - /* - * This isb() is required to prevent that the seq lock is - * speculated.# - */ - isb(); + */ + asm volatile( + ALTERNATIVE("isb\n" + "mrs %0, cntvct_el0", + "nop\n" + __mrs_s("%0", SYS_CNTVCTSS_EL0), + ARM64_HAS_ECV) + : "=r" (res) + : + : "memory"); + + arch_counter_enforce_ordering(res); return res; } @@ -98,6 +105,14 @@ const struct vdso_data *__arch_get_vdso_data(void) return _vdso_data; } +#ifdef CONFIG_TIME_NS +static __always_inline +const struct vdso_data *__arch_get_timens_vdso_data(const struct vdso_data *vd) +{ + return _timens_data; +} +#endif + #endif /* !__ASSEMBLY__ */ #endif /* __ASM_VDSO_GETTIMEOFDAY_H */ |