diff options
Diffstat (limited to 'lib/vdso/gettimeofday.c')
| -rw-r--r-- | lib/vdso/gettimeofday.c | 153 |
1 files changed, 100 insertions, 53 deletions
diff --git a/lib/vdso/gettimeofday.c b/lib/vdso/gettimeofday.c index f8b8ec5e63ac..a2909af4b924 100644 --- a/lib/vdso/gettimeofday.c +++ b/lib/vdso/gettimeofday.c @@ -2,30 +2,9 @@ /* * Generic userspace implementations of gettimeofday() and similar. */ -#include <linux/compiler.h> -#include <linux/math64.h> -#include <linux/time.h> -#include <linux/kernel.h> -#include <linux/hrtimer_defs.h> #include <vdso/datapage.h> #include <vdso/helpers.h> -/* - * The generic vDSO implementation requires that gettimeofday.h - * provides: - * - __arch_get_vdso_data(): to get the vdso datapage. - * - __arch_get_hw_counter(): to get the hw counter based on the - * clock_mode. - * - gettimeofday_fallback(): fallback for gettimeofday. - * - clock_gettime_fallback(): fallback for clock_gettime. - * - clock_getres_fallback(): fallback for clock_getres. - */ -#ifdef ENABLE_COMPAT_VDSO -#include <asm/vdso/compat_gettimeofday.h> -#else -#include <asm/vdso/gettimeofday.h> -#endif /* ENABLE_COMPAT_VDSO */ - #ifndef vdso_calc_delta /* * Default implementation which works for all sane clocksources. That @@ -38,6 +17,27 @@ u64 vdso_calc_delta(u64 cycles, u64 last, u64 mask, u32 mult) } #endif +#ifndef vdso_shift_ns +static __always_inline u64 vdso_shift_ns(u64 ns, u32 shift) +{ + return ns >> shift; +} +#endif + +#ifndef __arch_vdso_hres_capable +static inline bool __arch_vdso_hres_capable(void) +{ + return true; +} +#endif + +#ifndef vdso_clocksource_ok +static inline bool vdso_clocksource_ok(const struct vdso_data *vd) +{ + return vd->clock_mode != VDSO_CLOCKMODE_NONE; +} +#endif + #ifdef CONFIG_TIME_NS static int do_hres_timens(const struct vdso_data *vdns, clockid_t clk, struct __kernel_timespec *ts) @@ -57,14 +57,15 @@ static int do_hres_timens(const struct vdso_data *vdns, clockid_t clk, do { seq = vdso_read_begin(vd); + + if (unlikely(!vdso_clocksource_ok(vd))) + return -1; + cycles = __arch_get_hw_counter(vd->clock_mode); ns = vdso_ts->nsec; last = vd->cycle_last; - if (unlikely((s64)cycles < 0)) - return -1; - ns += vdso_calc_delta(cycles, last, vd->mask, vd->mult); - ns >>= vd->shift; + ns = vdso_shift_ns(ns, vd->shift); sec = vdso_ts->sec; } while (unlikely(vdso_read_retry(vd, seq))); @@ -101,12 +102,16 @@ static __always_inline int do_hres(const struct vdso_data *vd, clockid_t clk, u64 cycles, last, sec, ns; u32 seq; + /* Allows to compile the high resolution parts out */ + if (!__arch_vdso_hres_capable()) + return -1; + do { /* - * Open coded to handle VCLOCK_TIMENS. Time namespace + * Open coded to handle VDSO_CLOCKMODE_TIMENS. Time namespace * enabled tasks have a special VVAR page installed which * has vd->seq set to 1 and vd->clock_mode set to - * VCLOCK_TIMENS. For non time namespace affected tasks + * VDSO_CLOCKMODE_TIMENS. For non time namespace affected tasks * this does not affect performance because if vd->seq is * odd, i.e. a concurrent update is in progress the extra * check for vd->clock_mode is just a few extra @@ -115,20 +120,20 @@ static __always_inline int do_hres(const struct vdso_data *vd, clockid_t clk, */ while (unlikely((seq = READ_ONCE(vd->seq)) & 1)) { if (IS_ENABLED(CONFIG_TIME_NS) && - vd->clock_mode == VCLOCK_TIMENS) + vd->clock_mode == VDSO_CLOCKMODE_TIMENS) return do_hres_timens(vd, clk, ts); cpu_relax(); } smp_rmb(); + if (unlikely(!vdso_clocksource_ok(vd))) + return -1; + cycles = __arch_get_hw_counter(vd->clock_mode); ns = vdso_ts->nsec; last = vd->cycle_last; - if (unlikely((s64)cycles < 0)) - return -1; - ns += vdso_calc_delta(cycles, last, vd->mask, vd->mult); - ns >>= vd->shift; + ns = vdso_shift_ns(ns, vd->shift); sec = vdso_ts->sec; } while (unlikely(vdso_read_retry(vd, seq))); @@ -187,12 +192,12 @@ static __always_inline int do_coarse(const struct vdso_data *vd, clockid_t clk, do { /* - * Open coded to handle VCLOCK_TIMENS. See comment in + * Open coded to handle VDSO_CLOCK_TIMENS. See comment in * do_hres(). */ while ((seq = READ_ONCE(vd->seq)) & 1) { if (IS_ENABLED(CONFIG_TIME_NS) && - vd->clock_mode == VCLOCK_TIMENS) + vd->clock_mode == VDSO_CLOCKMODE_TIMENS) return do_coarse_timens(vd, clk, ts); cpu_relax(); } @@ -206,9 +211,9 @@ static __always_inline int do_coarse(const struct vdso_data *vd, clockid_t clk, } static __maybe_unused int -__cvdso_clock_gettime_common(clockid_t clock, struct __kernel_timespec *ts) +__cvdso_clock_gettime_common(const struct vdso_data *vd, clockid_t clock, + struct __kernel_timespec *ts) { - const struct vdso_data *vd = __arch_get_vdso_data(); u32 msk; /* Check for negative values or invalid clocks */ @@ -233,23 +238,31 @@ __cvdso_clock_gettime_common(clockid_t clock, struct __kernel_timespec *ts) } static __maybe_unused int -__cvdso_clock_gettime(clockid_t clock, struct __kernel_timespec *ts) +__cvdso_clock_gettime_data(const struct vdso_data *vd, clockid_t clock, + struct __kernel_timespec *ts) { - int ret = __cvdso_clock_gettime_common(clock, ts); + int ret = __cvdso_clock_gettime_common(vd, clock, ts); if (unlikely(ret)) return clock_gettime_fallback(clock, ts); return 0; } +static __maybe_unused int +__cvdso_clock_gettime(clockid_t clock, struct __kernel_timespec *ts) +{ + return __cvdso_clock_gettime_data(__arch_get_vdso_data(), clock, ts); +} + #ifdef BUILD_VDSO32 static __maybe_unused int -__cvdso_clock_gettime32(clockid_t clock, struct old_timespec32 *res) +__cvdso_clock_gettime32_data(const struct vdso_data *vd, clockid_t clock, + struct old_timespec32 *res) { struct __kernel_timespec ts; int ret; - ret = __cvdso_clock_gettime_common(clock, &ts); + ret = __cvdso_clock_gettime_common(vd, clock, &ts); if (unlikely(ret)) return clock_gettime32_fallback(clock, res); @@ -260,12 +273,18 @@ __cvdso_clock_gettime32(clockid_t clock, struct old_timespec32 *res) return ret; } + +static __maybe_unused int +__cvdso_clock_gettime32(clockid_t clock, struct old_timespec32 *res) +{ + return __cvdso_clock_gettime32_data(__arch_get_vdso_data(), clock, res); +} #endif /* BUILD_VDSO32 */ static __maybe_unused int -__cvdso_gettimeofday(struct __kernel_old_timeval *tv, struct timezone *tz) +__cvdso_gettimeofday_data(const struct vdso_data *vd, + struct __kernel_old_timeval *tv, struct timezone *tz) { - const struct vdso_data *vd = __arch_get_vdso_data(); if (likely(tv != NULL)) { struct __kernel_timespec ts; @@ -279,7 +298,7 @@ __cvdso_gettimeofday(struct __kernel_old_timeval *tv, struct timezone *tz) if (unlikely(tz != NULL)) { if (IS_ENABLED(CONFIG_TIME_NS) && - vd->clock_mode == VCLOCK_TIMENS) + vd->clock_mode == VDSO_CLOCKMODE_TIMENS) vd = __arch_get_timens_vdso_data(); tz->tz_minuteswest = vd[CS_HRES_COARSE].tz_minuteswest; @@ -289,13 +308,20 @@ __cvdso_gettimeofday(struct __kernel_old_timeval *tv, struct timezone *tz) return 0; } +static __maybe_unused int +__cvdso_gettimeofday(struct __kernel_old_timeval *tv, struct timezone *tz) +{ + return __cvdso_gettimeofday_data(__arch_get_vdso_data(), tv, tz); +} + #ifdef VDSO_HAS_TIME -static __maybe_unused __kernel_old_time_t __cvdso_time(__kernel_old_time_t *time) +static __maybe_unused __kernel_old_time_t +__cvdso_time_data(const struct vdso_data *vd, __kernel_old_time_t *time) { - const struct vdso_data *vd = __arch_get_vdso_data(); __kernel_old_time_t t; - if (IS_ENABLED(CONFIG_TIME_NS) && vd->clock_mode == VCLOCK_TIMENS) + if (IS_ENABLED(CONFIG_TIME_NS) && + vd->clock_mode == VDSO_CLOCKMODE_TIMENS) vd = __arch_get_timens_vdso_data(); t = READ_ONCE(vd[CS_HRES_COARSE].basetime[CLOCK_REALTIME].sec); @@ -305,13 +331,18 @@ static __maybe_unused __kernel_old_time_t __cvdso_time(__kernel_old_time_t *time return t; } + +static __maybe_unused __kernel_old_time_t __cvdso_time(__kernel_old_time_t *time) +{ + return __cvdso_time_data(__arch_get_vdso_data(), time); +} #endif /* VDSO_HAS_TIME */ #ifdef VDSO_HAS_CLOCK_GETRES static __maybe_unused -int __cvdso_clock_getres_common(clockid_t clock, struct __kernel_timespec *res) +int __cvdso_clock_getres_common(const struct vdso_data *vd, clockid_t clock, + struct __kernel_timespec *res) { - const struct vdso_data *vd = __arch_get_vdso_data(); u32 msk; u64 ns; @@ -319,7 +350,8 @@ int __cvdso_clock_getres_common(clockid_t clock, struct __kernel_timespec *res) if (unlikely((u32) clock >= MAX_CLOCKS)) return -1; - if (IS_ENABLED(CONFIG_TIME_NS) && vd->clock_mode == VCLOCK_TIMENS) + if (IS_ENABLED(CONFIG_TIME_NS) && + vd->clock_mode == VDSO_CLOCKMODE_TIMENS) vd = __arch_get_timens_vdso_data(); /* @@ -349,23 +381,31 @@ int __cvdso_clock_getres_common(clockid_t clock, struct __kernel_timespec *res) } static __maybe_unused -int __cvdso_clock_getres(clockid_t clock, struct __kernel_timespec *res) +int __cvdso_clock_getres_data(const struct vdso_data *vd, clockid_t clock, + struct __kernel_timespec *res) { - int ret = __cvdso_clock_getres_common(clock, res); + int ret = __cvdso_clock_getres_common(vd, clock, res); if (unlikely(ret)) return clock_getres_fallback(clock, res); return 0; } +static __maybe_unused +int __cvdso_clock_getres(clockid_t clock, struct __kernel_timespec *res) +{ + return __cvdso_clock_getres_data(__arch_get_vdso_data(), clock, res); +} + #ifdef BUILD_VDSO32 static __maybe_unused int -__cvdso_clock_getres_time32(clockid_t clock, struct old_timespec32 *res) +__cvdso_clock_getres_time32_data(const struct vdso_data *vd, clockid_t clock, + struct old_timespec32 *res) { struct __kernel_timespec ts; int ret; - ret = __cvdso_clock_getres_common(clock, &ts); + ret = __cvdso_clock_getres_common(vd, clock, &ts); if (unlikely(ret)) return clock_getres32_fallback(clock, res); @@ -376,5 +416,12 @@ __cvdso_clock_getres_time32(clockid_t clock, struct old_timespec32 *res) } return ret; } + +static __maybe_unused int +__cvdso_clock_getres_time32(clockid_t clock, struct old_timespec32 *res) +{ + return __cvdso_clock_getres_time32_data(__arch_get_vdso_data(), + clock, res); +} #endif /* BUILD_VDSO32 */ #endif /* VDSO_HAS_CLOCK_GETRES */ |