* Wei Huang (w...@redhat.com) wrote:
> This patch adds the migration test support for aarch64. The test code,
> which implements the same functionality as x86, is compiled into a binary
> and booted as a kernel to qemu. Here are the design ideas:
>
> * We choose this -kernel design because aarch64 QEMU doesn't provide a
> built-in fw like x86 does. So instead of relying on a boot loader, we
> use -kernel approach for aarch64.
> * The serial output is sent to PL011 directly.
> * The physical memory base for mach-virt machine is 0x40000000. We have
> to change the start_address and end_address for aarch64.
> * The downtime is changed from 0.001 to 0.1. Without this change, we saw
> migration stalled. This problem is still under analysis and needs to be
> resolved before removing RFC for this patch.
Where does the stall happen and what state is it in?
That downtime is set really small so that migration does *not* complete
without entering postcopy, so you should see it enter postcopy and then
complete.
Dave
> The test code is as the following:
>
> .section .text
>
> .globl start
>
> start:
> /* disable MMU to use phys mem address, just in case */
> mrs x0, sctlr_el1
> bic x0, x0, #(1<<0)
> msr sctlr_el1, x0
> isb
>
> /* output char 'A' to PL011 */
> mov w4, #65
> mov x5, #0x9000000
> strb w4, [x5]
>
> /* w6 keeps a counter so we limit the output speed */
> mov w6, #0
>
> mov x3, #(0x40000000 + 100 * 1024 * 1024)
> mainloop:
> mov x2, #(0x40000000 + 1024*1024) /* base addr = 0x40000000 */
>
> innerloop:
> ldrb w1, [x2]
> add w1, w1, #1
> strb w1, [x2]
>
> add x2, x2, #(4096)
> cmp x2, x3
> blt innerloop
>
> add w6, w6, #1
> and w6, w6, #(0xff)
> cmp w6, #0
> bne mainloop
>
> /* output char 'B' to PL011 */
> mov w4, #66
> mov x5, #0x9000000
> strb w4, [x5]
>
> bl mainloop
>
> The code is compiled with the following command:
> * gcc -c -o fill.o fill.s
> * gcc -O2 -o fill.elf -Wl,-T,/tmp/flat.lds,--build-id=none,-Ttext=40080000 \
> -nostdlib fill.o
> * objcopy -O binary fill.elf fill.flat
> * xxd -i fill.flat
>
> The linker file (borrowed from KVM unit test) is defined as:
>
> SECTIONS
> {
> .text : { *(.init) *(.text) *(.text.*) }
> . = ALIGN(64K);
> etext = .;
> .data : {
> *(.data)
> }
> . = ALIGN(16);
> .rodata : { *(.rodata) }
> . = ALIGN(16);
> .bss : { *(.bss) }
> . = ALIGN(64K);
> edata = .;
> . += 64K;
> . = ALIGN(64K);
> /*
> * stack depth is 16K for arm and PAGE_SIZE for arm64, see THREAD_SIZE
> * sp must be 16 byte aligned for arm64, and 8 byte aligned for arm
> * sp must always be strictly less than the true stacktop
> */
> stackptr = . - 16;
> stacktop = .;
> }
>
> ENTRY(start)
>
> Signed-off-by: Wei Huang <w...@redhat.com>
> ---
> tests/Makefile.include | 1 +
> tests/migration-test.c | 43 ++++++++++++++++++++++++++++++++++++++++---
> 2 files changed, 41 insertions(+), 3 deletions(-)
>
> diff --git a/tests/Makefile.include b/tests/Makefile.include
> index c002352..d5828c4 100644
> --- a/tests/Makefile.include
> +++ b/tests/Makefile.include
> @@ -357,6 +357,7 @@ check-qtest-arm-y += tests/test-arm-mptimer$(EXESUF)
> gcov-files-arm-y += hw/timer/arm_mptimer.c
>
> check-qtest-aarch64-y = tests/numa-test$(EXESUF)
> +check-qtest-aarch64-y += tests/migration-test$(EXESUF)
>
> check-qtest-microblazeel-y = $(check-qtest-microblaze-y)
>
> diff --git a/tests/migration-test.c b/tests/migration-test.c
> index be598d3..b0dd365 100644
> --- a/tests/migration-test.c
> +++ b/tests/migration-test.c
> @@ -22,8 +22,8 @@
>
> #define MIN_NVRAM_SIZE 8192 /* from spapr_nvram.c */
>
> -const unsigned start_address = 1024 * 1024;
> -const unsigned end_address = 100 * 1024 * 1024;
> +unsigned start_address = 1024 * 1024;
> +unsigned end_address = 100 * 1024 * 1024;
> bool got_stop;
>
> #if defined(__linux__)
> @@ -125,6 +125,18 @@ unsigned char bootsect[] = {
> 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x55, 0xaa
> };
>
> +unsigned char aarch64_kernel[] = {
> + 0x00, 0x10, 0x38, 0xd5, 0x00, 0xf8, 0x7f, 0x92, 0x00, 0x10, 0x18, 0xd5,
> + 0xdf, 0x3f, 0x03, 0xd5, 0x24, 0x08, 0x80, 0x52, 0x05, 0x20, 0xa1, 0xd2,
> + 0xa4, 0x00, 0x00, 0x39, 0x06, 0x00, 0x80, 0x52, 0x03, 0xc8, 0xa8, 0xd2,
> + 0x02, 0x02, 0xa8, 0xd2, 0x41, 0x00, 0x40, 0x39, 0x21, 0x04, 0x00, 0x11,
> + 0x41, 0x00, 0x00, 0x39, 0x42, 0x04, 0x40, 0x91, 0x5f, 0x00, 0x03, 0xeb,
> + 0x6b, 0xff, 0xff, 0x54, 0xc6, 0x04, 0x00, 0x11, 0xc6, 0x1c, 0x00, 0x12,
> + 0xdf, 0x00, 0x00, 0x71, 0xc1, 0xfe, 0xff, 0x54, 0x44, 0x08, 0x80, 0x52,
> + 0x05, 0x20, 0xa1, 0xd2, 0xa4, 0x00, 0x00, 0x39, 0xf2, 0xff, 0xff, 0x97
> +};
> +unsigned int aarch64_kernel_len = 96;
> +
> static void init_bootfile_x86(const char *bootpath)
> {
> FILE *bootfile = fopen(bootpath, "wb");
> @@ -163,6 +175,15 @@ static void init_bootfile_ppc(const char *bootpath)
> fclose(bootfile);
> }
>
> +static void init_bootfile_aarch64(const char *bootpath)
> +{
> + FILE *kernelfile = fopen(bootpath, "wb");
> +
> + g_assert_cmpint(fwrite(aarch64_kernel, aarch64_kernel_len, 1,
> kernelfile),
> + ==, 1);
> + fclose(kernelfile);
> +}
> +
> /*
> * Wait for some output in the serial output file,
> * we get an 'A' followed by an endless string of 'B's
> @@ -470,6 +491,22 @@ static void test_migrate_start(QTestState **from,
> QTestState **to,
> " -serial file:%s/dest_serial"
> " -incoming %s",
> accel, tmpfs, uri);
> + } else if (strcmp(arch, "aarch64") == 0) {
> + init_bootfile_aarch64(bootpath);
> + cmd_src = g_strdup_printf("-machine virt,accel=kvm:cg -m 1024M"
> + " -name vmsource,debug-threads=on -cpu
> host"
> + " -serial file:%s/src_serial "
> + " -kernel %s ",
> + tmpfs, bootpath);
> + cmd_dst = g_strdup_printf("-machine virt,accel=kvm:tcg -m 1024M"
> + " -name vmdest,debug-threads=on -cpu host"
> + " -serial file:%s/dest_serial"
> + " -kernel %s"
> + " -incoming %s",
> + tmpfs, bootpath, uri);
> + /* aarch64 virt machine physical mem started from 0x40000000 */
> + start_address += 0x40000000;
> + end_address += 0x40000000;
> } else {
> g_assert_not_reached();
> }
> @@ -530,7 +567,7 @@ static void test_migrate(void)
> * machine, so also set the downtime.
> */
> migrate_set_speed(from, "100000000");
> - migrate_set_downtime(from, 0.001);
> + migrate_set_downtime(from, 0.1);
>
> /* Wait for the first serial output from the source */
> wait_for_serial("src_serial");
> --
> 1.8.3.1
>
--
Dr. David Alan Gilbert / dgilb...@redhat.com / Manchester, UK
