diff options
Diffstat (limited to 'arch/x86/xen/time.c')
-rw-r--r-- | arch/x86/xen/time.c | 115 |
1 files changed, 31 insertions, 84 deletions
diff --git a/arch/x86/xen/time.c b/arch/x86/xen/time.c index f1ba6a092854..a0a4e554c6f1 100644 --- a/arch/x86/xen/time.c +++ b/arch/x86/xen/time.c @@ -16,6 +16,7 @@ #include <linux/gfp.h> #include <linux/slab.h> #include <linux/pvclock_gtod.h> +#include <linux/timekeeper_internal.h> #include <asm/pvclock.h> #include <asm/xen/hypervisor.h> @@ -32,86 +33,12 @@ #define TIMER_SLOP 100000 #define NS_PER_TICK (1000000000LL / HZ) -/* runstate info updated by Xen */ -static DEFINE_PER_CPU(struct vcpu_runstate_info, xen_runstate); - /* snapshots of runstate info */ static DEFINE_PER_CPU(struct vcpu_runstate_info, xen_runstate_snapshot); /* unused ns of stolen time */ static DEFINE_PER_CPU(u64, xen_residual_stolen); -/* return an consistent snapshot of 64-bit time/counter value */ -static u64 get64(const u64 *p) -{ - u64 ret; - - if (BITS_PER_LONG < 64) { - u32 *p32 = (u32 *)p; - u32 h, l; - - /* - * Read high then low, and then make sure high is - * still the same; this will only loop if low wraps - * and carries into high. - * XXX some clean way to make this endian-proof? - */ - do { - h = p32[1]; - barrier(); - l = p32[0]; - barrier(); - } while (p32[1] != h); - - ret = (((u64)h) << 32) | l; - } else - ret = *p; - - return ret; -} - -/* - * Runstate accounting - */ -static void get_runstate_snapshot(struct vcpu_runstate_info *res) -{ - u64 state_time; - struct vcpu_runstate_info *state; - - BUG_ON(preemptible()); - - state = this_cpu_ptr(&xen_runstate); - - /* - * The runstate info is always updated by the hypervisor on - * the current CPU, so there's no need to use anything - * stronger than a compiler barrier when fetching it. - */ - do { - state_time = get64(&state->state_entry_time); - barrier(); - *res = *state; - barrier(); - } while (get64(&state->state_entry_time) != state_time); -} - -/* return true when a vcpu could run but has no real cpu to run on */ -bool xen_vcpu_stolen(int vcpu) -{ - return per_cpu(xen_runstate, vcpu).state == RUNSTATE_runnable; -} - -void xen_setup_runstate_info(int cpu) -{ - struct vcpu_register_runstate_memory_area area; - - area.addr.v = &per_cpu(xen_runstate, cpu); - - if (HYPERVISOR_vcpu_op(VCPUOP_register_runstate_memory_area, - cpu, &area)) - BUG(); -} - static void do_stolen_accounting(void) { struct vcpu_runstate_info state; @@ -119,7 +46,7 @@ static void do_stolen_accounting(void) s64 runnable, offline, stolen; cputime_t ticks; - get_runstate_snapshot(&state); + xen_get_runstate_snapshot(&state); WARN_ON(state.state != RUNSTATE_running); @@ -194,26 +121,46 @@ static int xen_pvclock_gtod_notify(struct notifier_block *nb, unsigned long was_set, void *priv) { /* Protected by the calling core code serialization */ - static struct timespec next_sync; + static struct timespec64 next_sync; struct xen_platform_op op; - struct timespec now; + struct timespec64 now; + struct timekeeper *tk = priv; + static bool settime64_supported = true; + int ret; - now = __current_kernel_time(); + now.tv_sec = tk->xtime_sec; + now.tv_nsec = (long)(tk->tkr_mono.xtime_nsec >> tk->tkr_mono.shift); /* * We only take the expensive HV call when the clock was set * or when the 11 minutes RTC synchronization time elapsed. */ - if (!was_set && timespec_compare(&now, &next_sync) < 0) + if (!was_set && timespec64_compare(&now, &next_sync) < 0) return NOTIFY_OK; - op.cmd = XENPF_settime; - op.u.settime.secs = now.tv_sec; - op.u.settime.nsecs = now.tv_nsec; - op.u.settime.system_time = xen_clocksource_read(); +again: + if (settime64_supported) { + op.cmd = XENPF_settime64; + op.u.settime64.mbz = 0; + op.u.settime64.secs = now.tv_sec; + op.u.settime64.nsecs = now.tv_nsec; + op.u.settime64.system_time = xen_clocksource_read(); + } else { + op.cmd = XENPF_settime32; + op.u.settime32.secs = now.tv_sec; + op.u.settime32.nsecs = now.tv_nsec; + op.u.settime32.system_time = xen_clocksource_read(); + } + + ret = HYPERVISOR_platform_op(&op); - (void)HYPERVISOR_dom0_op(&op); + if (ret == -ENOSYS && settime64_supported) { + settime64_supported = false; + goto again; + } + if (ret < 0) + return NOTIFY_BAD; /* * Move the next drift compensation time 11 minutes |