[PATCH 2/3] xen: move do_stolen_accounting to drivers/xen/time.c
Stefano Stabellini
stefano.stabellini at eu.citrix.com
Wed May 1 15:27:39 EDT 2013
Move do_stolen_accounting, xen_vcpu_stolen and related functions and
static variables to common code (drivers/xen/time.c).
Signed-off-by: Stefano Stabellini <stefano.stabellini at eu.citrix.com>
---
arch/x86/xen/time.c | 127 +-------------------------------------------
drivers/xen/Makefile | 2 +-
drivers/xen/time.c | 142 +++++++++++++++++++++++++++++++++++++++++++++++++
include/xen/xen-ops.h | 4 ++
4 files changed, 148 insertions(+), 127 deletions(-)
create mode 100644 drivers/xen/time.c
diff --git a/arch/x86/xen/time.c b/arch/x86/xen/time.c
index 0296a95..278b7c2 100644
--- a/arch/x86/xen/time.c
+++ b/arch/x86/xen/time.c
@@ -28,131 +28,6 @@
/* Xen may fire a timer up to this many ns early */
#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 and blocked time */
-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;
- struct vcpu_runstate_info *snap;
- s64 blocked, runnable, offline, stolen;
- cputime_t ticks;
-
- get_runstate_snapshot(&state);
-
- WARN_ON(state.state != RUNSTATE_running);
-
- snap = &__get_cpu_var(xen_runstate_snapshot);
-
- /* work out how much time the VCPU has not been runn*ing* */
- blocked = state.time[RUNSTATE_blocked] - snap->time[RUNSTATE_blocked];
- 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);
-
- /* Add the appropriate number of ticks of blocked time,
- including any left-overs from last time. */
- blocked += __this_cpu_read(xen_residual_blocked);
-
- if (blocked < 0)
- blocked = 0;
-
- ticks = iter_div_u64_rem(blocked, NS_PER_TICK, &blocked);
- __this_cpu_write(xen_residual_blocked, blocked);
- account_idle_ticks(ticks);
-}
/* Get the TSC speed from Xen */
static unsigned long xen_tsc_khz(void)
@@ -390,7 +265,7 @@ static irqreturn_t xen_timer_interrupt(int irq, void *dev_id)
ret = IRQ_HANDLED;
}
- do_stolen_accounting();
+ xen_stolen_accounting();
return ret;
}
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..d00ed24
--- /dev/null
+++ b/drivers/xen/time.c
@@ -0,0 +1,142 @@
+/*
+ * 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>
+
+#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 and blocked time */
+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();
+}
+
+void xen_stolen_accounting(void)
+{
+ struct vcpu_runstate_info state;
+ struct vcpu_runstate_info *snap;
+ s64 blocked, runnable, offline, stolen;
+ cputime_t ticks;
+
+ get_runstate_snapshot(&state);
+
+ WARN_ON(state.state != RUNSTATE_running);
+
+ snap = &__get_cpu_var(xen_runstate_snapshot);
+
+ /* work out how much time the VCPU has not been runn*ing* */
+ blocked = state.time[RUNSTATE_blocked] - snap->time[RUNSTATE_blocked];
+ 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);
+
+ /* Add the appropriate number of ticks of blocked time,
+ including any left-overs from last time. */
+ blocked += __this_cpu_read(xen_residual_blocked);
+
+ if (blocked < 0)
+ blocked = 0;
+
+ ticks = iter_div_u64_rem(blocked, NS_PER_TICK, &blocked);
+ __this_cpu_write(xen_residual_blocked, blocked);
+ account_idle_ticks(ticks);
+}
diff --git a/include/xen/xen-ops.h b/include/xen/xen-ops.h
index d6fe062..85bb673 100644
--- a/include/xen/xen-ops.h
+++ b/include/xen/xen-ops.h
@@ -16,6 +16,10 @@ 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_stolen_accounting(void);
+
int xen_setup_shutdown_event(void);
extern unsigned long *xen_contiguous_bitmap;
--
1.7.2.5
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