[PATCH RFC v2 1/4] xen: move xen_setup_runstate_info and get_runstate_snapshot to drivers/xen/time.c
Stefano Stabellini
stefano.stabellini at eu.citrix.com
Mon May 6 10:51:15 EDT 2013
Changes in v2:
- leave do_stolen_accounting in arch/x86/xen/time.c;
- use the new common functions in arch/ia64/xen/time.c.
Signed-off-by: Stefano Stabellini <stefano.stabellini at eu.citrix.com>
Acked-by: Ian Campbell <ian.campbell at citrix.com>
CC: konrad.wilk at oracle.com
---
arch/ia64/xen/time.c | 48 +++----------------------
arch/x86/xen/time.c | 76 +----------------------------------------
drivers/xen/Makefile | 2 +-
drivers/xen/time.c | 91 +++++++++++++++++++++++++++++++++++++++++++++++++
include/xen/xen-ops.h | 5 +++
5 files changed, 104 insertions(+), 118 deletions(-)
create mode 100644 drivers/xen/time.c
diff --git a/arch/ia64/xen/time.c b/arch/ia64/xen/time.c
index 1f8244a..79a0b8c 100644
--- a/arch/ia64/xen/time.c
+++ b/arch/ia64/xen/time.c
@@ -34,53 +34,17 @@
#include "../kernel/fsyscall_gtod_data.h"
-static DEFINE_PER_CPU(struct vcpu_runstate_info, xen_runstate);
static DEFINE_PER_CPU(unsigned long, xen_stolen_time);
static DEFINE_PER_CPU(unsigned long, xen_blocked_time);
/* taken from i386/kernel/time-xen.c */
static void xen_init_missing_ticks_accounting(int cpu)
{
- struct vcpu_register_runstate_memory_area area;
- struct vcpu_runstate_info *runstate = &per_cpu(xen_runstate, cpu);
- int rc;
+ xen_setup_runstate_info(&runstate);
- memset(runstate, 0, sizeof(*runstate));
-
- area.addr.v = runstate;
- rc = HYPERVISOR_vcpu_op(VCPUOP_register_runstate_memory_area, cpu,
- &area);
- WARN_ON(rc && rc != -ENOSYS);
-
- per_cpu(xen_blocked_time, cpu) = runstate->time[RUNSTATE_blocked];
- per_cpu(xen_stolen_time, cpu) = runstate->time[RUNSTATE_runnable]
- + runstate->time[RUNSTATE_offline];
-}
-
-/*
- * Runstate accounting
- */
-/* stolen from arch/x86/xen/time.c */
-static void get_runstate_snapshot(struct vcpu_runstate_info *res)
-{
- u64 state_time;
- struct vcpu_runstate_info *state;
-
- BUG_ON(preemptible());
-
- state = &__get_cpu_var(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 = state->state_entry_time;
- rmb();
- *res = *state;
- rmb();
- } while (state->state_entry_time != state_time);
+ per_cpu(xen_blocked_time, cpu) = runstate.time[RUNSTATE_blocked];
+ per_cpu(xen_stolen_time, cpu) = runstate.time[RUNSTATE_runnable]
+ + runstate.time[RUNSTATE_offline];
}
#define NS_PER_TICK (1000000000LL/HZ)
@@ -94,7 +58,7 @@ consider_steal_time(unsigned long new_itm)
struct vcpu_runstate_info runstate;
struct task_struct *p = current;
- get_runstate_snapshot(&runstate);
+ xen_get_runstate_snapshot(&runstate);
/*
* Check for vcpu migration effect
@@ -202,7 +166,7 @@ static unsigned long long xen_sched_clock(void)
*/
now = ia64_native_sched_clock();
- get_runstate_snapshot(&runstate);
+ xen_get_runstate_snapshot(&runstate);
WARN_ON(runstate.state != RUNSTATE_running);
diff --git a/arch/x86/xen/time.c b/arch/x86/xen/time.c
index 0296a95..18d0104 100644
--- a/arch/x86/xen/time.c
+++ b/arch/x86/xen/time.c
@@ -30,9 +30,6 @@
#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);
@@ -40,77 +37,6 @@ static DEFINE_PER_CPU(struct vcpu_runstate_info, xen_runstate_snapshot);
static DEFINE_PER_CPU(u64, xen_residual_stolen);
static DEFINE_PER_CPU(u64, xen_residual_blocked);
-/* 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 = &__get_cpu_var(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;
@@ -118,7 +44,7 @@ static void do_stolen_accounting(void)
s64 blocked, runnable, offline, stolen;
cputime_t ticks;
- get_runstate_snapshot(&state);
+ xen_get_runstate_snapshot(&state);
WARN_ON(state.state != RUNSTATE_running);
diff --git a/drivers/xen/Makefile b/drivers/xen/Makefile
index eabd0ee..2bf461a 100644
--- a/drivers/xen/Makefile
+++ b/drivers/xen/Makefile
@@ -3,7 +3,7 @@ obj-y += manage.o
obj-$(CONFIG_HOTPLUG_CPU) += cpu_hotplug.o
endif
obj-$(CONFIG_X86) += fallback.o
-obj-y += grant-table.o features.o events.o balloon.o
+obj-y += grant-table.o features.o events.o balloon.o time.o
obj-y += xenbus/
nostackp := $(call cc-option, -fno-stack-protector)
diff --git a/drivers/xen/time.c b/drivers/xen/time.c
new file mode 100644
index 0000000..c2e39d3
--- /dev/null
+++ b/drivers/xen/time.c
@@ -0,0 +1,91 @@
+/*
+ * Xen stolen ticks accounting.
+ */
+#include <linux/kernel.h>
+#include <linux/kernel_stat.h>
+#include <linux/math64.h>
+#include <linux/gfp.h>
+
+#include <asm/xen/hypervisor.h>
+#include <asm/xen/hypercall.h>
+
+#include <xen/events.h>
+#include <xen/features.h>
+#include <xen/interface/xen.h>
+#include <xen/interface/vcpu.h>
+#include <xen/xen-ops.h>
+
+/* runstate info updated by Xen */
+static DEFINE_PER_CPU(struct vcpu_runstate_info, xen_runstate);
+
+/* 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
+ */
+void xen_get_runstate_snapshot(struct vcpu_runstate_info *res)
+{
+ u64 state_time;
+ struct vcpu_runstate_info *state;
+
+ BUG_ON(preemptible());
+
+ state = &__get_cpu_var(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();
+}
+
diff --git a/include/xen/xen-ops.h b/include/xen/xen-ops.h
index d6fe062..4fd4e47 100644
--- a/include/xen/xen-ops.h
+++ b/include/xen/xen-ops.h
@@ -3,6 +3,7 @@
#include <linux/percpu.h>
#include <asm/xen/interface.h>
+#include <xen/interface/vcpu.h>
DECLARE_PER_CPU(struct vcpu_info *, xen_vcpu);
@@ -16,6 +17,10 @@ void xen_mm_unpin_all(void);
void xen_timer_resume(void);
void xen_arch_resume(void);
+bool xen_vcpu_stolen(int vcpu);
+void xen_setup_runstate_info(int cpu);
+void xen_get_runstate_snapshot(struct vcpu_runstate_info *res);
+
int xen_setup_shutdown_event(void);
extern unsigned long *xen_contiguous_bitmap;
--
1.7.2.5
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