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x86_64/vdso: Move getcpu code from vsyscall_64.c to vdso/vma.c

Browse source 
This is pure cut-and-paste.  At this point, vsyscall_64.c
contains only code needed for vsyscall emulation, but some of
the comments and function names are still confused.

Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Link: http://lkml.kernel.org/r/a244daf7d3cbe71afc08ad09fdfe1866ca1f1978.1411494540.git.luto@amacapital.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This commit is contained in:
Andy Lutomirski 2014-09-23 10:50:52 -07:00 committed by Ingo Molnar
parent b93590901a
commit d4f829dd90
2 changed files with 61 additions and 57 deletions
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57
arch/x86/kernel/vsyscall_64.c
View file

@ -332,49 +332,6 @@ int in_gate_area_no_mm(unsigned long addr)
return (addr & PAGE_MASK) == VSYSCALL_ADDR;
}
/*
* Assume __initcall executes before all user space. Hopefully kmod
* doesn't violate that. We'll find out if it does.
*/
static void vsyscall_set_cpu(int cpu)
{
unsigned long d;
unsigned long node = 0;
#ifdef CONFIG_NUMA
node = cpu_to_node(cpu);
#endif
if (cpu_has(&cpu_data(cpu), X86_FEATURE_RDTSCP))
write_rdtscp_aux((node << 12) | cpu);
/*
* Store cpu number in limit so that it can be loaded quickly
* in user space in vgetcpu. (12 bits for the CPU and 8 bits for the node)
*/
d = 0x0f40000000000ULL;
d |= cpu;
d |= (node & 0xf) << 12;
d |= (node >> 4) << 48;
write_gdt_entry(get_cpu_gdt_table(cpu), GDT_ENTRY_PER_CPU, &d, DESCTYPE_S);
}
static void cpu_vsyscall_init(void *arg)
{
/* preemption should be already off */
vsyscall_set_cpu(raw_smp_processor_id());
}
static int
cpu_vsyscall_notifier(struct notifier_block *n, unsigned long action, void *arg)
{
long cpu = (long)arg;
if (action == CPU_ONLINE || action == CPU_ONLINE_FROZEN)
smp_call_function_single(cpu, cpu_vsyscall_init, NULL, 1);
return NOTIFY_DONE;
}
void __init map_vsyscall(void)
{
extern char __vsyscall_page;
@ -387,17 +344,3 @@ void __init map_vsyscall(void)
BUILD_BUG_ON((unsigned long)__fix_to_virt(VSYSCALL_PAGE) !=
(unsigned long)VSYSCALL_ADDR);
}
static int __init vsyscall_init(void)
{
cpu_notifier_register_begin();
on_each_cpu(cpu_vsyscall_init, NULL, 1);
/* notifier priority > KVM */
__hotcpu_notifier(cpu_vsyscall_notifier, 30);
cpu_notifier_register_done();
return 0;
}
__initcall(vsyscall_init);

61
arch/x86/vdso/vma.c
View file

@ -10,12 +10,14 @@
#include <linux/init.h>
#include <linux/random.h>
#include <linux/elf.h>
#include <linux/cpu.h>
#include <asm/vsyscall.h>
#include <asm/vgtod.h>
#include <asm/proto.h>
#include <asm/vdso.h>
#include <asm/page.h>
#include <asm/hpet.h>
#include <asm/desc.h>
#if defined(CONFIG_X86_64)
unsigned int __read_mostly vdso64_enabled = 1;
@ -238,3 +240,62 @@ static __init int vdso_setup(char *s)
}
__setup("vdso=", vdso_setup);
#endif
#ifdef CONFIG_X86_64
/*
* Assume __initcall executes before all user space. Hopefully kmod
* doesn't violate that. We'll find out if it does.
*/
static void vsyscall_set_cpu(int cpu)
{
unsigned long d;
unsigned long node = 0;
#ifdef CONFIG_NUMA
node = cpu_to_node(cpu);
#endif
if (cpu_has(&cpu_data(cpu), X86_FEATURE_RDTSCP))
write_rdtscp_aux((node << 12) | cpu);
/*
* Store cpu number in limit so that it can be loaded quickly
* in user space in vgetcpu. (12 bits for the CPU and 8 bits for the node)
*/
d = 0x0f40000000000ULL;
d |= cpu;
d |= (node & 0xf) << 12;
d |= (node >> 4) << 48;
write_gdt_entry(get_cpu_gdt_table(cpu), GDT_ENTRY_PER_CPU, &d, DESCTYPE_S);
}
static void cpu_vsyscall_init(void *arg)
{
/* preemption should be already off */
vsyscall_set_cpu(raw_smp_processor_id());
}
static int
cpu_vsyscall_notifier(struct notifier_block *n, unsigned long action, void *arg)
{
long cpu = (long)arg;
if (action == CPU_ONLINE || action == CPU_ONLINE_FROZEN)
smp_call_function_single(cpu, cpu_vsyscall_init, NULL, 1);
return NOTIFY_DONE;
}
static int __init vsyscall_init(void)
{
cpu_notifier_register_begin();
on_each_cpu(cpu_vsyscall_init, NULL, 1);
/* notifier priority > KVM */
__hotcpu_notifier(cpu_vsyscall_notifier, 30);
cpu_notifier_register_done();
return 0;
}
__initcall(vsyscall_init);
#endif