diff options
| -rw-r--r-- | include/linux/clocksource.h | 12 | ||||
| -rw-r--r-- | kernel/time/clocksource.c | 9 | ||||
| -rw-r--r-- | kernel/time/vsyscall.c | 10 | ||||
| -rw-r--r-- | lib/vdso/Kconfig | 3 | ||||
| -rw-r--r-- | lib/vdso/gettimeofday.c | 13 |
5 files changed, 42 insertions, 5 deletions
diff --git a/include/linux/clocksource.h b/include/linux/clocksource.h index 2c4574b517d2..6d5ed1b4d24d 100644 --- a/include/linux/clocksource.h +++ b/include/linux/clocksource.h @@ -23,10 +23,19 @@ struct clocksource; struct module; -#ifdef CONFIG_ARCH_CLOCKSOURCE_DATA +#if defined(CONFIG_ARCH_CLOCKSOURCE_DATA) || \ + defined(CONFIG_GENERIC_VDSO_CLOCK_MODE) #include <asm/clocksource.h> #endif +enum vdso_clock_mode { + VDSO_CLOCKMODE_NONE, +#ifdef CONFIG_GENERIC_VDSO_CLOCK_MODE + VDSO_ARCH_CLOCKMODES, +#endif + VDSO_CLOCKMODE_MAX, +}; + /** * struct clocksource - hardware abstraction for a free running counter * Provides mostly state-free accessors to the underlying hardware. @@ -97,6 +106,7 @@ struct clocksource { const char *name; struct list_head list; int rating; + enum vdso_clock_mode vdso_clock_mode; unsigned long flags; int (*enable)(struct clocksource *cs); diff --git a/kernel/time/clocksource.c b/kernel/time/clocksource.c index 428beb69426a..7cb09c4cf21c 100644 --- a/kernel/time/clocksource.c +++ b/kernel/time/clocksource.c @@ -928,6 +928,15 @@ int __clocksource_register_scale(struct clocksource *cs, u32 scale, u32 freq) clocksource_arch_init(cs); +#ifdef CONFIG_GENERIC_VDSO_CLOCK_MODE + if (cs->vdso_clock_mode < 0 || + cs->vdso_clock_mode >= VDSO_CLOCKMODE_MAX) { + pr_warn("clocksource %s registered with invalid VDSO mode %d. Disabling VDSO support.\n", + cs->name, cs->vdso_clock_mode); + cs->vdso_clock_mode = VDSO_CLOCKMODE_NONE; + } +#endif + /* Initialize mult/shift and max_idle_ns */ __clocksource_update_freq_scale(cs, scale, freq); diff --git a/kernel/time/vsyscall.c b/kernel/time/vsyscall.c index 9577c89179cd..f9a5178c69bb 100644 --- a/kernel/time/vsyscall.c +++ b/kernel/time/vsyscall.c @@ -71,13 +71,19 @@ void update_vsyscall(struct timekeeper *tk) { struct vdso_data *vdata = __arch_get_k_vdso_data(); struct vdso_timestamp *vdso_ts; + s32 clock_mode; u64 nsec; /* copy vsyscall data */ vdso_write_begin(vdata); - vdata[CS_HRES_COARSE].clock_mode = __arch_get_clock_mode(tk); - vdata[CS_RAW].clock_mode = __arch_get_clock_mode(tk); +#ifdef CONFIG_GENERIC_VDSO_CLOCK_MODE + clock_mode = tk->tkr_mono.clock->vdso_clock_mode; +#else + clock_mode = __arch_get_clock_mode(tk); +#endif + vdata[CS_HRES_COARSE].clock_mode = clock_mode; + vdata[CS_RAW].clock_mode = clock_mode; /* CLOCK_REALTIME also required for time() */ vdso_ts = &vdata[CS_HRES_COARSE].basetime[CLOCK_REALTIME]; diff --git a/lib/vdso/Kconfig b/lib/vdso/Kconfig index d883ac299508..d9f43c84fcc6 100644 --- a/lib/vdso/Kconfig +++ b/lib/vdso/Kconfig @@ -30,4 +30,7 @@ config GENERIC_VDSO_TIME_NS Selected by architectures which support time namespaces in the VDSO +config GENERIC_VDSO_CLOCK_MODE + bool + endif diff --git a/lib/vdso/gettimeofday.c b/lib/vdso/gettimeofday.c index 5804e4e168e7..3f2d8b859130 100644 --- a/lib/vdso/gettimeofday.c +++ b/lib/vdso/gettimeofday.c @@ -7,6 +7,7 @@ #include <linux/time.h> #include <linux/kernel.h> #include <linux/hrtimer_defs.h> +#include <linux/clocksource.h> #include <vdso/datapage.h> #include <vdso/helpers.h> @@ -64,10 +65,14 @@ static int do_hres_timens(const struct vdso_data *vdns, clockid_t clk, do { seq = vdso_read_begin(vd); + if (IS_ENABLED(CONFIG_GENERIC_VDSO_CLOCK_MODE) && + vd->clock_mode == VDSO_CLOCKMODE_NONE) + return -1; cycles = __arch_get_hw_counter(vd->clock_mode); ns = vdso_ts->nsec; last = vd->cycle_last; - if (unlikely((s64)cycles < 0)) + if (!IS_ENABLED(CONFIG_GENERIC_VDSO_CLOCK_MODE) && + unlikely((s64)cycles < 0)) return -1; ns += vdso_calc_delta(cycles, last, vd->mask, vd->mult); @@ -132,10 +137,14 @@ static __always_inline int do_hres(const struct vdso_data *vd, clockid_t clk, } smp_rmb(); + if (IS_ENABLED(CONFIG_GENERIC_VDSO_CLOCK_MODE) && + vd->clock_mode == VDSO_CLOCKMODE_NONE) + return -1; cycles = __arch_get_hw_counter(vd->clock_mode); ns = vdso_ts->nsec; last = vd->cycle_last; - if (unlikely((s64)cycles < 0)) + if (!IS_ENABLED(CONFIG_GENERIC_VDSO_CLOCK_MODE) && + unlikely((s64)cycles < 0)) return -1; ns += vdso_calc_delta(cycles, last, vd->mask, vd->mult); |