Re: [Qemu-devel] [PATCH V6 3/4] tests/migration: Add migration-test header file

["Dr. David Alan Gilbert" <dgilbert@redhat.com>]

* Wei Huang (wei@redhat.com) wrote:
> 
> 
> On 02/27/2018 05:57 AM, Dr. David Alan Gilbert wrote:
> > * Wei Huang (wei@redhat.com) wrote:
> >> This patch moves the settings related migration-test from the
> >> migration-test.c file to a seperate header file. It also renames the
> >> x86-a-b-bootblock.s file extension from .s to .S, allowing gcc
> >> pre-processor to include the C-style header file correctly.
> >>
> >> Signed-off-by: Wei Huang <wei@redhat.com>
> >> Reviewed-by: Andrew Jones <drjones@redhat.com>
> >> ---
> >>  tests/migration-test.c                             | 28 +++++++++++-----------
> >>  tests/migration/Makefile                           |  4 ++--
> >>  tests/migration/migration-test.h                   | 18 ++++++++++++++
> >>  .../{x86-a-b-bootblock.s => x86-a-b-bootblock.S}   |  7 +++---
> >>  tests/migration/x86-a-b-bootblock.h                |  2 +-
> >>  5 files changed, 39 insertions(+), 20 deletions(-)
> >>  create mode 100644 tests/migration/migration-test.h
> >>  rename tests/migration/{x86-a-b-bootblock.s => x86-a-b-bootblock.S} (94%)
> >>
> >> diff --git a/tests/migration-test.c b/tests/migration-test.c
> >> index 74f9361bdd..c88b7e7a19 100644
> >> --- a/tests/migration-test.c
> >> +++ b/tests/migration-test.c
> >> @@ -21,10 +21,10 @@
> >>  #include "sysemu/sysemu.h"
> >>  #include "hw/nvram/chrp_nvram.h"
> >>  
> >> -#define MIN_NVRAM_SIZE 8192 /* from spapr_nvram.c */
> >> +#include "migration/migration-test.h"
> >>  
> >> -const unsigned start_address = 1024 * 1024;
> >> -const unsigned end_address = 100 * 1024 * 1024;
> >> +const unsigned start_address = TEST_MEM_START;
> >> +const unsigned end_address = TEST_MEM_END;
> >>  bool got_stop;
> >>  
> >>  #if defined(__linux__)
> >> @@ -77,8 +77,8 @@ static bool ufd_version_check(void)
> >>  
> >>  static const char *tmpfs;
> >>  
> >> -/* A simple PC boot sector that modifies memory (1-100MB) quickly
> >> - * outputting a 'B' every so often if it's still running.
> >> +/* The boot file modifies memory area in [start_address, end_address)
> >> + * repeatedly. It outputs a 'B' at a fixed rate while it's still running.
> >>   */
> >>  #include "tests/migration/x86-a-b-bootblock.h"
> >>  
> >> @@ -104,9 +104,8 @@ static void init_bootfile_ppc(const char *bootpath)
> >>      memcpy(header->name, "common", 6);
> >>      chrp_nvram_finish_partition(header, MIN_NVRAM_SIZE);
> >>  
> >> -    /* FW_MAX_SIZE is 4MB, but slof.bin is only 900KB,
> >> -     * so let's modify memory between 1MB and 100MB
> >> -     * to do like PC bootsector
> >> +    /* FW_MAX_SIZE is 4MB, but slof.bin is only 900KB. So it is OK to modify
> >> +     * memory between start_address and end_address like PC bootsector does.
> >>       */
> >>  
> >>      sprintf(buf + 16,
> >> @@ -263,11 +262,11 @@ static void wait_for_migration_pass(QTestState *who)
> >>  static void check_guests_ram(QTestState *who)
> >>  {
> >>      /* Our ASM test will have been incrementing one byte from each page from
> >> -     * 1MB to <100MB in order.
> >> -     * This gives us a constraint that any page's byte should be equal or less
> >> -     * than the previous pages byte (mod 256); and they should all be equal
> >> -     * except for one transition at the point where we meet the incrementer.
> >> -     * (We're running this with the guest stopped).
> >> +     * start_address to < end_address in order. This gives us a constraint
> >> +     * that any page's byte should be equal or less than the previous pages
> >> +     * byte (mod 256); and they should all be equal except for one transition
> >> +     * at the point where we meet the incrementer. (We're running this with
> >> +     * the guest stopped).
> > 
> > No, please don't modify the other architectures.
> > 
> > It's OK for you to get the start/end value from the define in the header
> > but we can't assume they're movable; they're architecture specific
> > values that are chosen to fit where we know we have RAM.
> 
> Drew didn't like the idea of having #define TEST_MEM_START/TEST_MEM_END
> in headerfile, and in the meanwhile, we still use 1MB/100MB in comments.
> Anyway we didn't modify the underneath semantic for other architectures.

The problem is you have to be VERY careful; because while it might make
sense to move the start for one architecture it might break on another.

Dave

> > 
> > Dave
> > 
> >>       */
> >>      unsigned address;
> >>      uint8_t first_byte;
> >> @@ -278,7 +277,8 @@ static void check_guests_ram(QTestState *who)
> >>      qtest_memread(who, start_address, &first_byte, 1);
> >>      last_byte = first_byte;
> >>  
> >> -    for (address = start_address + 4096; address < end_address; address += 4096)
> >> +    for (address = start_address + TEST_MEM_PAGE_SIZE; address < end_address;
> >> +         address += TEST_MEM_PAGE_SIZE)
> >>      {
> >>          uint8_t b;
> >>          qtest_memread(who, address, &b, 1);
> >> diff --git a/tests/migration/Makefile b/tests/migration/Makefile
> >> index 8fbedaa8b8..013b8d1f44 100644
> >> --- a/tests/migration/Makefile
> >> +++ b/tests/migration/Makefile
> >> @@ -25,8 +25,8 @@ include $(SRC_PATH)/rules.mak
> >>  
> >>  x86_64_cross_prefix := $(call find-cross-prefix,x86_64)
> >>  
> >> -x86-a-b-bootblock.h: x86-a-b-bootblock.s
> >> -	$(x86_64_cross_prefix)as --32 -march=i486 $< -o x86.o
> >> +x86-a-b-bootblock.h: x86-a-b-bootblock.S
> >> +	$(x86_64_cross_prefix)gcc -m32 -march=i486 -c $< -o x86.o
> >>  	$(x86_64_cross_prefix)objcopy -O binary x86.o x86.boot
> >>  	dd if=x86.boot of=x86.bootsect bs=256 count=2 skip=124
> >>  	echo "$$__note" > $@
> >> diff --git a/tests/migration/migration-test.h b/tests/migration/migration-test.h
> >> new file mode 100644
> >> index 0000000000..48b59b3281
> >> --- /dev/null
> >> +++ b/tests/migration/migration-test.h
> >> @@ -0,0 +1,18 @@
> >> +/*
> >> + * Copyright (c) 2018 Red Hat, Inc. and/or its affiliates
> >> + *
> >> + * This work is licensed under the terms of the GNU GPL, version 2 or later.
> >> + * See the COPYING file in the top-level directory.
> >> + */
> >> +#ifndef _TEST_MIGRATION_H_
> >> +#define _TEST_MIGRATION_H_
> >> +
> >> +/* Common */
> >> +#define TEST_MEM_START      (1 * 1024 * 1024)
> >> +#define TEST_MEM_END        (100 * 1024 * 1024)
> >> +#define TEST_MEM_PAGE_SIZE  4096
> >> +
> >> +/* PPC */
> >> +#define MIN_NVRAM_SIZE 8192 /* from spapr_nvram.c */
> >> +
> >> +#endif /* _TEST_MIGRATION_H_ */
> >> diff --git a/tests/migration/x86-a-b-bootblock.s b/tests/migration/x86-a-b-bootblock.S
> >> similarity index 94%
> >> rename from tests/migration/x86-a-b-bootblock.s
> >> rename to tests/migration/x86-a-b-bootblock.S
> >> index 98dbfab084..08b51f9e7f 100644
> >> --- a/tests/migration/x86-a-b-bootblock.s
> >> +++ b/tests/migration/x86-a-b-bootblock.S
> >> @@ -12,6 +12,7 @@
> >>  #
> >>  # Author: dgilbert@redhat.com
> >>  
> >> +#include "migration-test.h"
> >>  
> >>  .code16
> >>  .org 0x7c00
> >> @@ -45,11 +46,11 @@ start:             # at 0x7c00 ?
> >>          mov $0, %bl
> >>  mainloop:
> >>          # Start from 1MB
> >> -        mov $(1024*1024),%eax
> >> +        mov $TEST_MEM_START,%eax
> >>  innerloop:
> >>          incb (%eax)
> >> -        add $4096,%eax
> >> -        cmp $(100*1024*1024),%eax
> >> +        add $TEST_MEM_PAGE_SIZE,%eax
> >> +        cmp $TEST_MEM_END,%eax
> >>          jl innerloop
> >>  
> >>          inc %bl
> >> diff --git a/tests/migration/x86-a-b-bootblock.h b/tests/migration/x86-a-b-bootblock.h
> >> index 9e8e2e028b..44e4b99506 100644
> >> --- a/tests/migration/x86-a-b-bootblock.h
> >> +++ b/tests/migration/x86-a-b-bootblock.h
> >> @@ -1,5 +1,5 @@
> >>  /* This file is automatically generated from
> >> - * tests/migration/x86-a-b-bootblock.s, edit that and then run
> >> + * tests/migration/x86-a-b-bootblock.S, edit that and then run
> >>   * "make x86-a-b-bootblock.h" inside tests/migration to update,
> >>   * and then remember to send both in your patch submission.
> >>   */
> >> -- 
> >> 2.14.3
> >>
> > --
> > Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK
> > 
--
Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK