@@ -190,6 +190,25 @@ config HW_PERF_EVENTS
source "mm/Kconfig"
+config PARAVIRT
+ bool "Enable paravirtualization code"
+ ---help---
+ This changes the kernel so it can modify itself when it is run
+ under a hypervisor, potentially improving performance significantly
+ over full virtualization.
+
+config PARAVIRT_TIME_ACCOUNTING
+ bool "Paravirtual steal time accounting"
+ select PARAVIRT
+ default n
+ ---help---
+ Select this option to enable fine granularity task steal time
+ accounting. Time spent executing other tasks in parallel with
+ the current vCPU is discounted from the vCPU power. To account for
+ that, there can be a small performance impact.
+
+ If in doubt, say N here.
+
config XEN_DOM0
def_bool y
depends on XEN
@@ -197,6 +216,7 @@ config XEN_DOM0
config XEN
bool "Xen guest support on ARM64 (EXPERIMENTAL)"
depends on ARM64 && OF
+ select PARAVIRT
help
Say Y if you want to run Linux in a Virtual Machine on Xen on ARM64.
new file mode 100644
@@ -0,0 +1,20 @@
+#ifndef _ASM_ARM64_PARAVIRT_H
+#define _ASM_ARM64_PARAVIRT_H
+
+#ifdef CONFIG_PARAVIRT
+struct static_key;
+extern struct static_key paravirt_steal_enabled;
+extern struct static_key paravirt_steal_rq_enabled;
+
+struct pv_time_ops {
+ unsigned long long (*steal_clock)(int cpu);
+};
+extern struct pv_time_ops pv_time_ops;
+
+static inline u64 paravirt_steal_clock(int cpu)
+{
+ return pv_time_ops.steal_clock(cpu);
+}
+#endif
+
+#endif
@@ -18,6 +18,7 @@ arm64-obj-$(CONFIG_SMP) += smp.o smp_spin_table.o smp_psci.o
arm64-obj-$(CONFIG_HW_PERF_EVENTS) += perf_event.o
arm64-obj-$(CONFIG_HAVE_HW_BREAKPOINT)+= hw_breakpoint.o
arm64-obj-$(CONFIG_EARLY_PRINTK) += early_printk.o
+arm64-obj-$(CONFIG_PARAVIRT) += paravirt.o
obj-y += $(arm64-obj-y) vdso/
obj-m += $(arm64-obj-m)
new file mode 100644
@@ -0,0 +1,25 @@
+/*
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * Copyright (C) 2013 Citrix Systems
+ *
+ * Author: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
+ */
+
+#include <linux/export.h>
+#include <linux/jump_label.h>
+#include <linux/types.h>
+#include <asm/paravirt.h>
+
+struct static_key paravirt_steal_enabled;
+struct static_key paravirt_steal_rq_enabled;
+
+struct pv_time_ops pv_time_ops;
+EXPORT_SYMBOL_GPL(pv_time_ops);
Introduce CONFIG_PARAVIRT and PARAVIRT_TIME_ACCOUNTING on ARM64. Necessary duplication of paravirt.h and paravirt.c with ARM. The only paravirt interface supported is pv_time_ops.steal_clock, so no runtime pvops patching needed. This allows us to make use of steal_account_process_tick for stolen ticks accounting. Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> CC: will.deacon@arm.com CC: nico@linaro.org CC: marc.zyngier@arm.com CC: cov@codeaurora.org CC: arnd@arndb.de CC: olof@lixom.net CC: Catalin.Marinas@arm.com --- Changes in v7: - ifdef CONFIG_PARAVIRT the content of paravirt.h. --- arch/arm64/Kconfig | 20 ++++++++++++++++++++ arch/arm64/include/asm/paravirt.h | 20 ++++++++++++++++++++ arch/arm64/kernel/Makefile | 1 + arch/arm64/kernel/paravirt.c | 25 +++++++++++++++++++++++++ 4 files changed, 66 insertions(+), 0 deletions(-) create mode 100644 arch/arm64/include/asm/paravirt.h create mode 100644 arch/arm64/kernel/paravirt.c