@@ -39,7 +39,6 @@ obj-$(CONFIG_MEM_ACCESS) += mem_access.o
obj-y += mm.o
obj-y += monitor.o
obj-y += p2m.o
-obj-y += percpu.o
obj-y += platform.o
obj-y += platform_hypercall.o
obj-y += physdev.o
deleted file mode 100644
@@ -1,85 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0 */
-#include <xen/percpu.h>
-#include <xen/cpu.h>
-#include <xen/init.h>
-#include <xen/mm.h>
-#include <xen/rcupdate.h>
-
-unsigned long __per_cpu_offset[NR_CPUS];
-#define INVALID_PERCPU_AREA (-(long)__per_cpu_start)
-#define PERCPU_ORDER (get_order_from_bytes(__per_cpu_data_end-__per_cpu_start))
-
-void __init percpu_init_areas(void)
-{
- unsigned int cpu;
- for ( cpu = 1; cpu < NR_CPUS; cpu++ )
- __per_cpu_offset[cpu] = INVALID_PERCPU_AREA;
-}
-
-static int init_percpu_area(unsigned int cpu)
-{
- char *p;
- if ( __per_cpu_offset[cpu] != INVALID_PERCPU_AREA )
- return -EBUSY;
- if ( (p = alloc_xenheap_pages(PERCPU_ORDER, 0)) == NULL )
- return -ENOMEM;
- memset(p, 0, __per_cpu_data_end - __per_cpu_start);
- __per_cpu_offset[cpu] = p - __per_cpu_start;
- return 0;
-}
-
-struct free_info {
- unsigned int cpu;
- struct rcu_head rcu;
-};
-static DEFINE_PER_CPU(struct free_info, free_info);
-
-static void _free_percpu_area(struct rcu_head *head)
-{
- struct free_info *info = container_of(head, struct free_info, rcu);
- unsigned int cpu = info->cpu;
- char *p = __per_cpu_start + __per_cpu_offset[cpu];
- free_xenheap_pages(p, PERCPU_ORDER);
- __per_cpu_offset[cpu] = INVALID_PERCPU_AREA;
-}
-
-static void free_percpu_area(unsigned int cpu)
-{
- struct free_info *info = &per_cpu(free_info, cpu);
- info->cpu = cpu;
- call_rcu(&info->rcu, _free_percpu_area);
-}
-
-static int cpu_percpu_callback(
- struct notifier_block *nfb, unsigned long action, void *hcpu)
-{
- unsigned int cpu = (unsigned long)hcpu;
- int rc = 0;
-
- switch ( action )
- {
- case CPU_UP_PREPARE:
- rc = init_percpu_area(cpu);
- break;
- case CPU_UP_CANCELED:
- case CPU_DEAD:
- free_percpu_area(cpu);
- break;
- default:
- break;
- }
-
- return notifier_from_errno(rc);
-}
-
-static struct notifier_block cpu_percpu_nfb = {
- .notifier_call = cpu_percpu_callback,
- .priority = 100 /* highest priority */
-};
-
-static int __init percpu_presmp_init(void)
-{
- register_cpu_notifier(&cpu_percpu_nfb);
- return 0;
-}
-presmp_initcall(percpu_presmp_init);
@@ -141,7 +141,6 @@ void smp_send_state_dump(unsigned int cpu)
/* domain.c */
DEFINE_PER_CPU(struct vcpu *, curr_vcpu);
-unsigned long __per_cpu_offset[NR_CPUS];
void context_switch(struct vcpu *prev, struct vcpu *next)
{
@@ -133,7 +133,6 @@ void smp_send_state_dump(unsigned int cpu)
/* domain.c */
DEFINE_PER_CPU(struct vcpu *, curr_vcpu);
-unsigned long __per_cpu_offset[NR_CPUS];
void context_switch(struct vcpu *prev, struct vcpu *next)
{
@@ -1,3 +1,2 @@
# SPDX-License-Identifier: GPL-2.0-only
generic-y += div64.h
-generic-y += percpu.h
new file mode 100644
@@ -0,0 +1,18 @@
+#ifndef __X86_PERCPU_H__
+#define __X86_PERCPU_H__
+
+#include <asm-generic/percpu.h>
+
+/*
+ * Force uses of per_cpu() with an invalid area to attempt to access the
+ * middle of the non-canonical address space resulting in a #GP, rather than a
+ * possible #PF at (NULL + a little) which has security implications in the
+ * context of PV guests.
+ */
+#define INVALID_PERCPU_AREA (0x8000000000000000UL - (unsigned long)__per_cpu_start)
+
+#define ARCH_PERCPU_AREA_CHECK
+
+#define ARCH_CPU_PERCPU_CALLBACK
+
+#endif /* __X86_PERCPU_H__ */
@@ -1,79 +1,19 @@
-#include <xen/percpu.h>
#include <xen/cpu.h>
-#include <xen/init.h>
-#include <xen/mm.h>
-#include <xen/rcupdate.h>
-
-unsigned long __per_cpu_offset[NR_CPUS];
-
-/*
- * Force uses of per_cpu() with an invalid area to attempt to access the
- * middle of the non-canonical address space resulting in a #GP, rather than a
- * possible #PF at (NULL + a little) which has security implications in the
- * context of PV guests.
- */
-#define INVALID_PERCPU_AREA (0x8000000000000000UL - (unsigned long)__per_cpu_start)
-#define PERCPU_ORDER get_order_from_bytes(__per_cpu_data_end - __per_cpu_start)
-
-void __init percpu_init_areas(void)
-{
- unsigned int cpu;
-
- for ( cpu = 1; cpu < NR_CPUS; cpu++ )
- __per_cpu_offset[cpu] = INVALID_PERCPU_AREA;
-}
+#include <xen/percpu.h>
+#include <xen/smp.h>
-static int init_percpu_area(unsigned int cpu)
+int arch_percpu_area_init_status(void)
{
- char *p;
-
- if ( __per_cpu_offset[cpu] != INVALID_PERCPU_AREA )
- return 0;
-
- if ( (p = alloc_xenheap_pages(PERCPU_ORDER, 0)) == NULL )
- return -ENOMEM;
-
- memset(p, 0, __per_cpu_data_end - __per_cpu_start);
- __per_cpu_offset[cpu] = p - __per_cpu_start;
-
return 0;
}
-struct free_info {
- unsigned int cpu;
- struct rcu_head rcu;
-};
-static DEFINE_PER_CPU(struct free_info, free_info);
-
-static void cf_check _free_percpu_area(struct rcu_head *head)
-{
- struct free_info *info = container_of(head, struct free_info, rcu);
- unsigned int cpu = info->cpu;
- char *p = __per_cpu_start + __per_cpu_offset[cpu];
-
- free_xenheap_pages(p, PERCPU_ORDER);
- __per_cpu_offset[cpu] = INVALID_PERCPU_AREA;
-}
-
-static void free_percpu_area(unsigned int cpu)
-{
- struct free_info *info = &per_cpu(free_info, cpu);
-
- info->cpu = cpu;
- call_rcu(&info->rcu, _free_percpu_area);
-}
-
-static int cf_check cpu_percpu_callback(
- struct notifier_block *nfb, unsigned long action, void *hcpu)
+int arch_cpu_percpu_callback(struct notifier_block *nfb,
+ unsigned long action, void *hcpu)
{
unsigned int cpu = (unsigned long)hcpu;
- int rc = 0;
switch ( action )
{
- case CPU_UP_PREPARE:
- rc = init_percpu_area(cpu);
- break;
case CPU_UP_CANCELED:
case CPU_DEAD:
case CPU_RESUME_FAILED:
@@ -86,27 +26,5 @@ static int cf_check cpu_percpu_callback(
break;
}
- return notifier_from_errno(rc);
-}
-
-static struct notifier_block cpu_percpu_nfb = {
- .notifier_call = cpu_percpu_callback,
- .priority = 100 /* highest priority */
-};
-
-static int __init cf_check percpu_presmp_init(void)
-{
- register_cpu_notifier(&cpu_percpu_nfb);
-
return 0;
}
-presmp_initcall(percpu_presmp_init);
-
-/*
- * Local variables:
- * mode: C
- * c-file-style: "BSD"
- * c-basic-offset: 4
- * indent-tabs-mode: nil
- * End:
- */
@@ -31,6 +31,7 @@ obj-y += notifier.o
obj-$(CONFIG_NUMA) += numa.o
obj-y += page_alloc.o
obj-y += pdx.o
+obj-y += percpu.o
obj-$(CONFIG_PERF_COUNTERS) += perfc.o
obj-bin-$(CONFIG_HAS_PMAP) += pmap.init.o
obj-y += preempt.o
new file mode 100644
@@ -0,0 +1,127 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#include <xen/percpu.h>
+#include <xen/cpu.h>
+#include <xen/init.h>
+#include <xen/mm.h>
+#include <xen/rcupdate.h>
+
+unsigned long __per_cpu_offset[NR_CPUS];
+
+#ifndef INVALID_PERCPU_AREA
+#define INVALID_PERCPU_AREA (-(long)__per_cpu_start)
+#endif
+
+#ifndef ARCH_PERCPU_AREA_CHECK
+inline int arch_percpu_area_init_status(void)
+{
+ return -EBUSY;
+}
+#endif
+
+#ifndef ARCH_CPU_PERCPU_CALLBACK
+inline int arch_cpu_percpu_callback(struct notifier_block *nfb,
+ unsigned long action, void *hcpu)
+{
+ unsigned int cpu = (unsigned long)hcpu;
+
+ switch ( action )
+ {
+ case CPU_UP_CANCELED:
+ case CPU_DEAD:
+ free_percpu_area(cpu);
+ break;
+ }
+
+ return 0;
+}
+#endif
+
+#define PERCPU_ORDER get_order_from_bytes(__per_cpu_data_end - __per_cpu_start)
+
+void __init percpu_init_areas(void)
+{
+ unsigned int cpu;
+
+ for ( cpu = 1; cpu < NR_CPUS; cpu++ )
+ __per_cpu_offset[cpu] = INVALID_PERCPU_AREA;
+}
+
+static int init_percpu_area(unsigned int cpu)
+{
+ char *p;
+
+ if ( __per_cpu_offset[cpu] != INVALID_PERCPU_AREA )
+ return arch_percpu_area_init_status();
+
+ if ( (p = alloc_xenheap_pages(PERCPU_ORDER, 0)) == NULL )
+ return -ENOMEM;
+
+ memset(p, 0, __per_cpu_data_end - __per_cpu_start);
+ __per_cpu_offset[cpu] = p - __per_cpu_start;
+
+ return 0;
+}
+
+struct free_info {
+ unsigned int cpu;
+ struct rcu_head rcu;
+};
+static DEFINE_PER_CPU(struct free_info, free_info);
+
+static void cf_check _free_percpu_area(struct rcu_head *head)
+{
+ struct free_info *info = container_of(head, struct free_info, rcu);
+ unsigned int cpu = info->cpu;
+ char *p = __per_cpu_start + __per_cpu_offset[cpu];
+
+ free_xenheap_pages(p, PERCPU_ORDER);
+ __per_cpu_offset[cpu] = INVALID_PERCPU_AREA;
+}
+
+void free_percpu_area(unsigned int cpu)
+{
+ struct free_info *info = &per_cpu(free_info, cpu);
+
+ info->cpu = cpu;
+ call_rcu(&info->rcu, _free_percpu_area);
+}
+
+static int cf_check cpu_percpu_callback(
+ struct notifier_block *nfb, unsigned long action, void *hcpu)
+{
+ unsigned int cpu = (unsigned long)hcpu;
+ int rc = 0;
+
+ switch ( action )
+ {
+ case CPU_UP_PREPARE:
+ rc = init_percpu_area(cpu);
+ break;
+ default:
+ arch_cpu_percpu_callback(nfb, action, hcpu);
+ }
+
+ return notifier_from_errno(rc);
+}
+
+static struct notifier_block cpu_percpu_nfb = {
+ .notifier_call = cpu_percpu_callback,
+ .priority = 100 /* highest priority */
+};
+
+static int __init cf_check percpu_presmp_init(void)
+{
+ register_cpu_notifier(&cpu_percpu_nfb);
+
+ return 0;
+}
+presmp_initcall(percpu_presmp_init);
+
+/*
+ * Local variables:
+ * mode: C
+ * c-file-style: "BSD"
+ * c-basic-offset: 4
+ * indent-tabs-mode: nil
+ * End:
+ */
@@ -12,6 +12,14 @@ extern const char __per_cpu_data_end[];
extern unsigned long __per_cpu_offset[NR_CPUS];
void percpu_init_areas(void);
+void free_percpu_area(unsigned int cpu);
+
+int arch_percpu_area_init_status(void);
+
+struct notifier_block;
+int arch_cpu_percpu_callback(struct notifier_block *nfb,
+ unsigned long action, void *hcpu);
+
#define per_cpu(var, cpu) \
(*RELOC_HIDE(&per_cpu__##var, __per_cpu_offset[cpu]))
Centralize per-cpu area management to reduce code duplication and enhance maintainability across architectures. The per-cpu area management code, which is largely common among architectures, is moved to a shared implementation in xen/common/percpu.c. This change includes: * Add arch_percpu_area_init_status() and arch_cpu_percpu_callback() functions to address architecture-specific variations. * Remove percpu.c from the Arm architecture. * For x86, percpu.c now only defines arch_percpu_area_init_status() and arch_cpu_percpu_callback(), and INVALID_PERCPU_AREA. * Drop the declaration of __per_cpu_offset[] from stubs.c in PPC and RISC-V to facilitate the build of the common per-cpu code. No functional changes. Signed-off-by: Oleksii Kurochko <oleksii.kurochko@gmail.com> --- xen/arch/arm/Makefile | 1 - xen/arch/arm/percpu.c | 85 -------------------- xen/arch/ppc/stubs.c | 1 - xen/arch/riscv/stubs.c | 1 - xen/arch/x86/include/asm/Makefile | 1 - xen/arch/x86/include/asm/percpu.h | 18 +++++ xen/arch/x86/percpu.c | 92 ++-------------------- xen/common/Makefile | 1 + xen/common/percpu.c | 127 ++++++++++++++++++++++++++++++ xen/include/asm-generic/percpu.h | 8 ++ 10 files changed, 159 insertions(+), 176 deletions(-) delete mode 100644 xen/arch/arm/percpu.c create mode 100644 xen/arch/x86/include/asm/percpu.h create mode 100644 xen/common/percpu.c