blob: 8239e16e7ad41129b6e3dbf48a9004f90ad3af34 [file] [log] [blame] [edit]
/*
* Async PF test. For the test to actually do anything it needs to be started
* in memory cgroup with 512M of memory and with more then 1G memory provided
* to the guest.
*
* To create cgroup do as root:
* mkdir /dev/cgroup
* mount -t cgroup none -omemory /dev/cgroup
* chmod a+rxw /dev/cgroup/
*
* From a shell you will start qemu from:
* mkdir /dev/cgroup/1
* echo $$ > /dev/cgroup/1/tasks
* echo 512M > /dev/cgroup/1/memory.limit_in_bytes
*
*/
#include "x86/msr.h"
#include "x86/processor.h"
#include "x86/apic-defs.h"
#include "x86/apic.h"
#include "x86/desc.h"
#include "x86/isr.h"
#include "x86/vm.h"
#include "asm/page.h"
#include "alloc.h"
#include "libcflat.h"
#include "vmalloc.h"
#include <stdint.h>
#define KVM_PV_REASON_PAGE_NOT_PRESENT 1
#define KVM_PV_REASON_PAGE_READY 2
#define MSR_KVM_ASYNC_PF_EN 0x4b564d02
#define KVM_ASYNC_PF_ENABLED (1 << 0)
#define KVM_ASYNC_PF_SEND_ALWAYS (1 << 1)
volatile uint32_t apf_reason __attribute__((aligned(64)));
char *buf;
volatile uint64_t i;
volatile uint64_t phys;
static inline uint32_t get_apf_reason(void)
{
uint32_t r = apf_reason;
apf_reason = 0;
return r;
}
static void pf_isr(struct ex_regs *r)
{
void* virt = (void*)((ulong)(buf+i) & ~(PAGE_SIZE-1));
uint32_t reason = get_apf_reason();
switch (reason) {
case 0:
report(false, "unexpected #PF at %#lx", read_cr2());
break;
case KVM_PV_REASON_PAGE_NOT_PRESENT:
phys = virt_to_pte_phys(phys_to_virt(read_cr3()), virt);
install_pte(phys_to_virt(read_cr3()), 1, virt, phys, 0);
write_cr3(read_cr3());
report(true,
"Got not present #PF token %lx virt addr %p phys addr %#" PRIx64,
read_cr2(), virt, phys);
while(phys) {
safe_halt(); /* enables irq */
irq_disable();
}
break;
case KVM_PV_REASON_PAGE_READY:
report(true, "Got present #PF token %lx", read_cr2());
if ((uint32_t)read_cr2() == ~0)
break;
install_pte(phys_to_virt(read_cr3()), 1, virt, phys | PT_PRESENT_MASK | PT_WRITABLE_MASK, 0);
write_cr3(read_cr3());
phys = 0;
break;
default:
report(false, "unexpected async pf reason %" PRId32, reason);
break;
}
}
#define MEM 1ull*1024*1024*1024
int main(int ac, char **av)
{
int loop = 2;
setup_vm();
printf("install handler\n");
handle_exception(14, pf_isr);
apf_reason = 0;
printf("enable async pf\n");
wrmsr(MSR_KVM_ASYNC_PF_EN, virt_to_phys((void*)&apf_reason) |
KVM_ASYNC_PF_SEND_ALWAYS | KVM_ASYNC_PF_ENABLED);
printf("alloc memory\n");
buf = malloc(MEM);
irq_enable();
while(loop--) {
printf("start loop\n");
/* access a lot of memory to make host swap it out */
for (i=0; i < MEM; i+=4096)
buf[i] = 1;
printf("end loop\n");
}
irq_disable();
return report_summary();
}