diff mbox

[2/7] x86/kvmclock: Remove page size requirement from wall_clock

Message ID 20180706162049.387233770@linutronix.de (mailing list archive)
State New, archived
Headers show

Commit Message

Thomas Gleixner July 6, 2018, 4:13 p.m. UTC 
There is no requirement for wall_clock data to be page aligned or page
sized.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krcmar <rkrcmar@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Juergen Gross <jgross@suse.com>
Cc: Pavel Tatashin <pasha.tatashin@oracle.com>
Cc: steven.sistare@oracle.com
Cc: daniel.m.jordan@oracle.com
Cc: x86@kernel.org
Cc: kvm@vger.kernel.org
---
 arch/x86/kernel/kvmclock.c |   12 ++++--------
 1 file changed, 4 insertions(+), 8 deletions(-)

Comments

Pavel Tatashin July 12, 2018, 2:15 a.m. UTC | #1 
On Fri, Jul 6, 2018 at 12:26 PM Thomas Gleixner <tglx@linutronix.de> wrote:
>
> There is no requirement for wall_clock data to be page aligned or page
> sized.
>

Reviewed-by: Pavel Tatashin <pasha.tatashin@oracle.com>
diff mbox

Patch

--- a/arch/x86/kernel/kvmclock.c
+++ b/arch/x86/kernel/kvmclock.c
@@ -46,14 +46,12 @@  early_param("no-kvmclock", parse_no_kvmc
 
 /* Aligned to page sizes to match whats mapped via vsyscalls to userspace */
 #define HV_CLOCK_SIZE	(sizeof(struct pvclock_vsyscall_time_info) * NR_CPUS)
-#define WALL_CLOCK_SIZE	(sizeof(struct pvclock_wall_clock))
 
 static u8 hv_clock_mem[PAGE_ALIGN(HV_CLOCK_SIZE)] __aligned(PAGE_SIZE);
-static u8 wall_clock_mem[PAGE_ALIGN(WALL_CLOCK_SIZE)] __aligned(PAGE_SIZE);
 
 /* The hypervisor will put information about time periodically here */
 static struct pvclock_vsyscall_time_info *hv_clock;
-static struct pvclock_wall_clock *wall_clock;
+static struct pvclock_wall_clock wall_clock;
 
 /*
  * The wallclock is the time of day when we booted. Since then, some time may
@@ -66,15 +64,15 @@  static void kvm_get_wallclock(struct tim
 	int low, high;
 	int cpu;
 
-	low = (int)slow_virt_to_phys(wall_clock);
-	high = ((u64)slow_virt_to_phys(wall_clock) >> 32);
+	low = (int)slow_virt_to_phys(&wall_clock);
+	high = ((u64)slow_virt_to_phys(&wall_clock) >> 32);
 
 	native_write_msr(msr_kvm_wall_clock, low, high);
 
 	cpu = get_cpu();
 
 	vcpu_time = &hv_clock[cpu].pvti;
-	pvclock_read_wallclock(wall_clock, vcpu_time, now);
+	pvclock_read_wallclock(&wall_clock, vcpu_time, now);
 
 	put_cpu();
 }
@@ -266,12 +264,10 @@  void __init kvmclock_init(void)
 	} else if (!(kvmclock && kvm_para_has_feature(KVM_FEATURE_CLOCKSOURCE)))
 		return;
 
-	wall_clock = (struct pvclock_wall_clock *)wall_clock_mem;
 	hv_clock = (struct pvclock_vsyscall_time_info *)hv_clock_mem;
 
 	if (kvm_register_clock("primary cpu clock")) {
 		hv_clock = NULL;
-		wall_clock = NULL;
 		return;
 	}