[Qemu-devel] [PATCH V6 4/4] tests: Add migration test for aarch64

[Wei Huang <wei@redhat.com>]

This patch adds migration test support for aarch64. The test code, which
implements the same functionality as x86, is booted as a kernel in qemu.
Here are the design choices we make for aarch64:

 * We choose this -kernel approach 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 change
   the start_address and end_address for aarch64.

In addition to providing the binary, this patch also includes the source
code and the build script in tests/migration/. So users can change the
source and/or re-compile the binary as they wish.

Signed-off-by: Wei Huang <wei@redhat.com>
---
 tests/Makefile.include               |  1 +
 tests/migration-test.c               | 46 +++++++++++++++++++---
 tests/migration/Makefile             | 12 +++++-
 tests/migration/aarch64-a-b-kernel.S | 75 ++++++++++++++++++++++++++++++++++++
 tests/migration/aarch64-a-b-kernel.h | 19 +++++++++
 tests/migration/migration-test.h     |  9 +++++
 6 files changed, 154 insertions(+), 8 deletions(-)
 create mode 100644 tests/migration/aarch64-a-b-kernel.S
 create mode 100644 tests/migration/aarch64-a-b-kernel.h

diff --git a/tests/Makefile.include b/tests/Makefile.include
index 577eb573a2..538173866c 100644
--- a/tests/Makefile.include
+++ b/tests/Makefile.include
@@ -372,6 +372,7 @@ check-qtest-arm-y += tests/sdhci-test$(EXESUF)
 check-qtest-aarch64-y = tests/numa-test$(EXESUF)
 check-qtest-aarch64-y += tests/sdhci-test$(EXESUF)
 check-qtest-aarch64-y += tests/boot-serial-test$(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 c88b7e7a19..9cc98445b0 100644
--- a/tests/migration-test.c
+++ b/tests/migration-test.c
@@ -11,6 +11,7 @@
  */
 
 #include "qemu/osdep.h"
+#include <sys/utsname.h>
 
 #include "libqtest.h"
 #include "qapi/qmp/qdict.h"
@@ -23,8 +24,8 @@
 
 #include "migration/migration-test.h"
 
-const unsigned start_address = TEST_MEM_START;
-const unsigned end_address = TEST_MEM_END;
+unsigned start_address = TEST_MEM_START;
+unsigned end_address = TEST_MEM_END;
 bool got_stop;
 
 #if defined(__linux__)
@@ -81,12 +82,13 @@ static const char *tmpfs;
  * repeatedly. It outputs a 'B' at a fixed rate while it's still running.
  */
 #include "tests/migration/x86-a-b-bootblock.h"
+#include "tests/migration/aarch64-a-b-kernel.h"
 
-static void init_bootfile_x86(const char *bootpath)
+static void init_bootfile(const char *bootpath, void *content)
 {
     FILE *bootfile = fopen(bootpath, "wb");
 
-    g_assert_cmpint(fwrite(x86_bootsect, 512, 1, bootfile), ==, 1);
+    g_assert_cmpint(fwrite(content, 512, 1, bootfile), ==, 1);
     fclose(bootfile);
 }
 
@@ -392,7 +394,7 @@ static void test_migrate_start(QTestState **from, QTestState **to,
     got_stop = false;
 
     if (strcmp(arch, "i386") == 0 || strcmp(arch, "x86_64") == 0) {
-        init_bootfile_x86(bootpath);
+        init_bootfile(bootpath, x86_bootsect);
         cmd_src = g_strdup_printf("-machine accel=%s -m 150M"
                                   " -name source,debug-threads=on"
                                   " -serial file:%s/src_serial"
@@ -421,6 +423,38 @@ 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) {
+        const char *cpu;
+        const char *gic_ver;
+        struct utsname utsname;
+
+        /* kvm and tcg need different cpu and gic-version configs */
+        if (access("/dev/kvm", F_OK) == 0 && uname(&utsname) == 0 &&
+            strcmp(utsname.machine, "aarch64") == 0) {
+            accel = "kvm";
+            cpu = "host";
+            gic_ver = "host";
+        } else {
+            accel = "tcg";
+            cpu = "cortex-a57";
+            gic_ver = "2";
+        }
+
+        init_bootfile(bootpath, aarch64_kernel);
+        cmd_src = g_strdup_printf("-machine virt,accel=%s,gic-version=%s "
+                                  "-name vmsource,debug-threads=on -cpu %s "
+                                  "-m 150M -serial file:%s/src_serial "
+                                  "-kernel %s ",
+                                  accel, gic_ver, cpu, tmpfs, bootpath);
+        cmd_dst = g_strdup_printf("-machine virt,accel=%s,gic-version=%s "
+                                  "-name vmdest,debug-threads=on -cpu %s "
+                                  "-m 150M -serial file:%s/dest_serial "
+                                  "-kernel %s "
+                                  "-incoming %s ",
+                                  accel, gic_ver, cpu, tmpfs, bootpath, uri);
+
+        start_address = ARM_TEST_MEM_START;
+        end_address = ARM_TEST_MEM_END;
     } else {
         g_assert_not_reached();
     }
@@ -505,7 +539,7 @@ static void test_deprecated(void)
 {
     QTestState *from;
 
-    from = qtest_start("");
+    from = qtest_start("-machine none");
 
     deprecated_set_downtime(from, 0.12345);
     deprecated_set_speed(from, "12345");
diff --git a/tests/migration/Makefile b/tests/migration/Makefile
index 013b8d1f44..1324427a93 100644
--- a/tests/migration/Makefile
+++ b/tests/migration/Makefile
@@ -16,7 +16,7 @@ override define __note
  */
 endef
 
-all: x86-a-b-bootblock.h
+all: x86-a-b-bootblock.h aarch64-a-b-kernel.h
 # Dummy command so that make thinks it has done something
 	@true
 
@@ -24,6 +24,7 @@ SRC_PATH=../..
 include $(SRC_PATH)/rules.mak
 
 x86_64_cross_prefix := $(call find-cross-prefix,x86_64)
+aarch64_cross_prefix := $(call find-cross-prefix,aarch64)
 
 x86-a-b-bootblock.h: x86-a-b-bootblock.S
 	$(x86_64_cross_prefix)gcc -m32 -march=i486 -c $< -o x86.o
@@ -32,5 +33,12 @@ x86-a-b-bootblock.h: x86-a-b-bootblock.S
 	echo "$$__note" > $@
 	xxd -i x86.bootsect | sed -e 's/.*int.*//' >> $@
 
+aarch64-a-b-kernel.h: aarch64-a-b-kernel.S
+	$(aarch64_cross_prefix)gcc -o aarch64.elf -nostdlib \
+		-Wl,--build-id=none $<
+	$(aarch64_cross_prefix)objcopy -O binary aarch64.elf aarch64.kernel
+	echo "$$__note" > $@
+	xxd -i aarch64.kernel | sed -e 's/.*int.*//' >> $@
+
 clean:
-	rm -f *.bootsect *.boot *.o
+	rm -f *.bootsect *.boot *.o *.elf *.kernel
diff --git a/tests/migration/aarch64-a-b-kernel.S b/tests/migration/aarch64-a-b-kernel.S
new file mode 100644
index 0000000000..eec8f44f16
--- /dev/null
+++ b/tests/migration/aarch64-a-b-kernel.S
@@ -0,0 +1,75 @@
+#
+# Copyright (c) 2018 Red Hat, Inc. and/or its affiliates
+#
+# Author:
+#   Wei Huang <wei@redhat.com>
+#
+# This work is licensed under the terms of the GNU GPL, version 2 or later.
+# See the COPYING file in the top-level directory.
+#
+# Note: Please make sure the compiler compiles the assembly code below with
+# pc-relative address. Also the branch instructions should use relative
+# addresses only.
+
+#include "migration-test.h"
+
+.section .text
+
+        .globl  _start
+
+_start:
+        /* disable MMU to use phys mem address */
+        mrs     x0, sctlr_el1
+        bic     x0, x0, #(1<<0)
+        msr     sctlr_el1, x0
+        isb
+
+        /* traverse test memory region */
+        mov     x0, #ARM_TEST_MEM_START
+        mov     x1, #ARM_TEST_MEM_END
+
+        /* output char 'A' to PL011 */
+        mov     w3, 'A'
+        mov     x2, #ARM_MACH_VIRT_UART
+        strb    w3, [x2]
+
+        /* clean up memory */
+        mov     w3, #0
+        mov     x4, x0
+clean:
+        strb    w3, [x4]
+        add     x4, x4, #TEST_MEM_PAGE_SIZE
+        cmp     x4, x1
+        ble     clean
+
+        /* w5 keeps a counter so we can limit the output speed */
+        mov     w5, #0
+
+        /* main body */
+mainloop:
+        mov     x4, x0
+
+innerloop:
+        /* clean cache because el2 might still cache guest data under KVM */
+        dc      civac, x4
+
+        /* increment the first byte of each page by 1 */
+        ldrb    w3, [x4]
+        add     w3, w3, #1
+        and     w3, w3, #0xff
+        strb    w3, [x4]
+
+        add     x4, x4, #TEST_MEM_PAGE_SIZE
+        cmp     x4, x1
+        blt     innerloop
+
+        add     w5, w5, #1
+        and     w5, w5, #0xff
+        cmp     w5, #0
+        bne     mainloop
+
+        /* output char 'B' to PL011 */
+        mov     w3, 'B'
+        strb    w3, [x2]
+
+        b       mainloop
diff --git a/tests/migration/aarch64-a-b-kernel.h b/tests/migration/aarch64-a-b-kernel.h
new file mode 100644
index 0000000000..53b44d3e99
--- /dev/null
+++ b/tests/migration/aarch64-a-b-kernel.h
@@ -0,0 +1,19 @@
+/* This file is automatically generated from
+ * tests/migration/aarch64-a-b-kernel.S, edit that and then run
+ * "make aarch64-a-b-kernel.h" inside tests/migration to update,
+ * and then remember to send both in your patch submission.
+ */
+unsigned char aarch64_kernel[] = {
+  0x00, 0x10, 0x38, 0xd5, 0x00, 0xf8, 0x7f, 0x92, 0x00, 0x10, 0x18, 0xd5,
+  0xdf, 0x3f, 0x03, 0xd5, 0x00, 0x02, 0xa8, 0xd2, 0x01, 0xc8, 0xa8, 0xd2,
+  0x23, 0x08, 0x80, 0x52, 0x02, 0x20, 0xa1, 0xd2, 0x43, 0x00, 0x00, 0x39,
+  0x03, 0x00, 0x80, 0x52, 0xe4, 0x03, 0x00, 0xaa, 0x83, 0x00, 0x00, 0x39,
+  0x84, 0x04, 0x40, 0x91, 0x9f, 0x00, 0x01, 0xeb, 0xad, 0xff, 0xff, 0x54,
+  0x05, 0x00, 0x80, 0x52, 0xe4, 0x03, 0x00, 0xaa, 0x24, 0x7e, 0x0b, 0xd5,
+  0x83, 0x00, 0x40, 0x39, 0x63, 0x04, 0x00, 0x11, 0x63, 0x1c, 0x00, 0x12,
+  0x83, 0x00, 0x00, 0x39, 0x84, 0x04, 0x40, 0x91, 0x9f, 0x00, 0x01, 0xeb,
+  0x2b, 0xff, 0xff, 0x54, 0xa5, 0x04, 0x00, 0x11, 0xa5, 0x1c, 0x00, 0x12,
+  0xbf, 0x00, 0x00, 0x71, 0x81, 0xfe, 0xff, 0x54, 0x43, 0x08, 0x80, 0x52,
+  0x43, 0x00, 0x00, 0x39, 0xf1, 0xff, 0xff, 0x17
+};
+
diff --git a/tests/migration/migration-test.h b/tests/migration/migration-test.h
index 48b59b3281..65ae48b929 100644
--- a/tests/migration/migration-test.h
+++ b/tests/migration/migration-test.h
@@ -15,4 +15,13 @@
 /* PPC */
 #define MIN_NVRAM_SIZE 8192 /* from spapr_nvram.c */
 
+/* AArch64 */
+#define ARM_MACH_VIRT_UART  0x09000000
+/* AArch64 kernel load address is 0x40080000. It should be safe to start the
+ * test memory at 0x40000000 + TEST_MEM_START, which literally creates a 512KB
+ * space to host the kernel binary.
+ */
+#define ARM_TEST_MEM_START  (0x40000000 + TEST_MEM_START)
+#define ARM_TEST_MEM_END    (0x40000000 + TEST_MEM_END)
+
 #endif /* _TEST_MIGRATION_H_ */
-- 
2.14.3