diff options
| author | Juergen Gross | 2016-05-20 09:26:48 +0200 |
|---|---|---|
| committer | David Vrabel | 2016-07-06 10:34:48 +0100 |
| commit | ecb23dc6f2eff0ce64dd60351a81f376f13b12cc (patch) | |
| tree | 09536e5db2dc00af9dd5209fef72a1e1222f6cf2 /arch/x86/xen | |
| parent | c7ebf9d9c6b4e9402b978da0b0785db4129c1f79 (diff) | |
xen: add steal_clock support on x86
The pv_time_ops structure contains a function pointer for the
"steal_clock" functionality used only by KVM and Xen on ARM. Xen on x86
uses its own mechanism to account for the "stolen" time a thread wasn't
able to run due to hypervisor scheduling.
Add support in Xen arch independent time handling for this feature by
moving it out of the arm arch into drivers/xen and remove the x86 Xen
hack.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Diffstat (limited to 'arch/x86/xen')
| -rw-r--r-- | arch/x86/xen/time.c | 44 |
1 files changed, 2 insertions, 42 deletions
diff --git a/arch/x86/xen/time.c b/arch/x86/xen/time.c index 6deba5bc7e34..c31006f0f37f 100644 --- a/arch/x86/xen/time.c +++ b/arch/x86/xen/time.c @@ -11,8 +11,6 @@ #include <linux/interrupt.h> #include <linux/clocksource.h> #include <linux/clockchips.h> -#include <linux/kernel_stat.h> -#include <linux/math64.h> #include <linux/gfp.h> #include <linux/slab.h> #include <linux/pvclock_gtod.h> @@ -31,44 +29,6 @@ /* Xen may fire a timer up to this many ns early */ #define TIMER_SLOP 100000 -#define NS_PER_TICK (1000000000LL / HZ) - -/* 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); - -static void do_stolen_accounting(void) -{ - struct vcpu_runstate_info state; - struct vcpu_runstate_info *snap; - s64 runnable, offline, stolen; - cputime_t ticks; - - xen_get_runstate_snapshot(&state); - - WARN_ON(state.state != RUNSTATE_running); - - snap = this_cpu_ptr(&xen_runstate_snapshot); - - /* work out how much time the VCPU has not been runn*ing* */ - runnable = state.time[RUNSTATE_runnable] - snap->time[RUNSTATE_runnable]; - offline = state.time[RUNSTATE_offline] - snap->time[RUNSTATE_offline]; - - *snap = state; - - /* Add the appropriate number of ticks of stolen time, - including any left-overs from last time. */ - stolen = runnable + offline + __this_cpu_read(xen_residual_stolen); - - if (stolen < 0) - stolen = 0; - - ticks = iter_div_u64_rem(stolen, NS_PER_TICK, &stolen); - __this_cpu_write(xen_residual_stolen, stolen); - account_steal_ticks(ticks); -} /* Get the TSC speed from Xen */ static unsigned long xen_tsc_khz(void) @@ -335,8 +295,6 @@ static irqreturn_t xen_timer_interrupt(int irq, void *dev_id) ret = IRQ_HANDLED; } - do_stolen_accounting(); - return ret; } @@ -431,6 +389,8 @@ static void __init xen_time_init(void) xen_setup_timer(cpu); xen_setup_cpu_clockevents(); + xen_time_setup_guest(); + if (xen_initial_domain()) pvclock_gtod_register_notifier(&xen_pvclock_gtod_notifier); } |