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authorJosé Pekkarinen <jose.pekkarinen@nokia.com>2016-04-11 10:41:07 +0300
committerJosé Pekkarinen <jose.pekkarinen@nokia.com>2016-04-13 08:17:18 +0300
commite09b41010ba33a20a87472ee821fa407a5b8da36 (patch)
treed10dc367189862e7ca5c592f033dc3726e1df4e3 /kernel/arch/x86/kernel/kvmclock.c
parentf93b97fd65072de626c074dbe099a1fff05ce060 (diff)
These changes are the raw update to linux-4.4.6-rt14. Kernel sources
are taken from kernel.org, and rt patch from the rt wiki download page. During the rebasing, the following patch collided: Force tick interrupt and get rid of softirq magic(I70131fb85). Collisions have been removed because its logic was found on the source already. Change-Id: I7f57a4081d9deaa0d9ccfc41a6c8daccdee3b769 Signed-off-by: José Pekkarinen <jose.pekkarinen@nokia.com>
Diffstat (limited to 'kernel/arch/x86/kernel/kvmclock.c')
-rw-r--r--kernel/arch/x86/kernel/kvmclock.c48
1 files changed, 41 insertions, 7 deletions
diff --git a/kernel/arch/x86/kernel/kvmclock.c b/kernel/arch/x86/kernel/kvmclock.c
index 42caaef89..2bd81e302 100644
--- a/kernel/arch/x86/kernel/kvmclock.c
+++ b/kernel/arch/x86/kernel/kvmclock.c
@@ -24,6 +24,7 @@
#include <linux/percpu.h>
#include <linux/hardirq.h>
#include <linux/memblock.h>
+#include <linux/sched.h>
#include <asm/x86_init.h>
#include <asm/reboot.h>
@@ -31,6 +32,7 @@
static int kvmclock = 1;
static int msr_kvm_system_time = MSR_KVM_SYSTEM_TIME;
static int msr_kvm_wall_clock = MSR_KVM_WALL_CLOCK;
+static cycle_t kvm_sched_clock_offset;
static int parse_no_kvmclock(char *arg)
{
@@ -91,6 +93,29 @@ static cycle_t kvm_clock_get_cycles(struct clocksource *cs)
return kvm_clock_read();
}
+static cycle_t kvm_sched_clock_read(void)
+{
+ return kvm_clock_read() - kvm_sched_clock_offset;
+}
+
+static inline void kvm_sched_clock_init(bool stable)
+{
+ if (!stable) {
+ pv_time_ops.sched_clock = kvm_clock_read;
+ return;
+ }
+
+ kvm_sched_clock_offset = kvm_clock_read();
+ pv_time_ops.sched_clock = kvm_sched_clock_read;
+ set_sched_clock_stable();
+
+ printk(KERN_INFO "kvm-clock: using sched offset of %llu cycles\n",
+ kvm_sched_clock_offset);
+
+ BUILD_BUG_ON(sizeof(kvm_sched_clock_offset) >
+ sizeof(((struct pvclock_vcpu_time_info *)NULL)->system_time));
+}
+
/*
* If we don't do that, there is the possibility that the guest
* will calibrate under heavy load - thus, getting a lower lpj -
@@ -199,7 +224,7 @@ static void kvm_setup_secondary_clock(void)
* kind of shutdown from our side, we unregister the clock by writting anything
* that does not have the 'enable' bit set in the msr
*/
-#ifdef CONFIG_KEXEC
+#ifdef CONFIG_KEXEC_CORE
static void kvm_crash_shutdown(struct pt_regs *regs)
{
native_write_msr(msr_kvm_system_time, 0, 0);
@@ -217,8 +242,10 @@ static void kvm_shutdown(void)
void __init kvmclock_init(void)
{
+ struct pvclock_vcpu_time_info *vcpu_time;
unsigned long mem;
- int size;
+ int size, cpu;
+ u8 flags;
size = PAGE_ALIGN(sizeof(struct pvclock_vsyscall_time_info)*NR_CPUS);
@@ -245,7 +272,17 @@ void __init kvmclock_init(void)
memblock_free(mem, size);
return;
}
- pv_time_ops.sched_clock = kvm_clock_read;
+
+ if (kvm_para_has_feature(KVM_FEATURE_CLOCKSOURCE_STABLE_BIT))
+ pvclock_set_flags(PVCLOCK_TSC_STABLE_BIT);
+
+ cpu = get_cpu();
+ vcpu_time = &hv_clock[cpu].pvti;
+ flags = pvclock_read_flags(vcpu_time);
+
+ kvm_sched_clock_init(flags & PVCLOCK_TSC_STABLE_BIT);
+ put_cpu();
+
x86_platform.calibrate_tsc = kvm_get_tsc_khz;
x86_platform.get_wallclock = kvm_get_wallclock;
x86_platform.set_wallclock = kvm_set_wallclock;
@@ -256,15 +293,12 @@ void __init kvmclock_init(void)
x86_platform.save_sched_clock_state = kvm_save_sched_clock_state;
x86_platform.restore_sched_clock_state = kvm_restore_sched_clock_state;
machine_ops.shutdown = kvm_shutdown;
-#ifdef CONFIG_KEXEC
+#ifdef CONFIG_KEXEC_CORE
machine_ops.crash_shutdown = kvm_crash_shutdown;
#endif
kvm_get_preset_lpj();
clocksource_register_hz(&kvm_clock, NSEC_PER_SEC);
pv_info.name = "KVM";
-
- if (kvm_para_has_feature(KVM_FEATURE_CLOCKSOURCE_STABLE_BIT))
- pvclock_set_flags(PVCLOCK_TSC_STABLE_BIT);
}
int __init kvm_setup_vsyscall_timeinfo(void)