Re: [Qemu-devel] [PATCH V9 2/4] tests/migration: Support cross compilation in generating boot header file

["Alex Bennée" <alex.bennee@linaro.org>]

Wei Huang <wei@redhat.com> writes:

> Recently a new configure option, CROSS_CC_GUEST, was added to
> $(TARGET)-softmmu/config-target.mak to support TCG-related tests. This
> patch tries to leverage this option to support cross compilation when the
> migration boot block file is being re-generated:
>
>  * The x86 related files are moved to a new sub-dir (named ./i386).
>  * A new top-layer Makefile is created in tests/migration/ directory.
>    This Makefile searches and parses CROSS_CC_GUEST to generate CROSS_PREFIX.
>    The CROSS_PREFIX, if available, is then passed to migration/$ARCH/Makefile.
>
> Reviewed-by: Juan Quintela <quintela@redhat.com>
> Signed-off-by: Wei Huang <wei@redhat.com>
> ---
>  tests/migration-test.c                             |  2 +-
>  tests/migration/Makefile                           | 44 ++++++++++++----------
>  tests/migration/i386/Makefile                      | 22 +++++++++++
>  .../{x86-a-b-bootblock.S => i386/a-b-bootblock.S}  |  4 --
>  .../{x86-a-b-bootblock.h => i386/a-b-bootblock.h}  |  8 ++--
>  5 files changed, 51 insertions(+), 29 deletions(-)
>  create mode 100644 tests/migration/i386/Makefile
>  rename tests/migration/{x86-a-b-bootblock.S => i386/a-b-bootblock.S} (93%)
>  rename tests/migration/{x86-a-b-bootblock.h => i386/a-b-bootblock.h} (92%)
>
> diff --git a/tests/migration-test.c b/tests/migration-test.c
> index 0e687b7..fe6b41a 100644
> --- a/tests/migration-test.c
> +++ b/tests/migration-test.c
> @@ -83,7 +83,7 @@ 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.
>   */
> -#include "tests/migration/x86-a-b-bootblock.h"
> +#include "tests/migration/i386/a-b-bootblock.h"
>
>  static void init_bootfile_x86(const char *bootpath)
>  {
> diff --git a/tests/migration/Makefile b/tests/migration/Makefile
> index c0824b4..a9ed875 100644
> --- a/tests/migration/Makefile
> +++ b/tests/migration/Makefile
> @@ -1,31 +1,35 @@
> -# To specify cross compiler prefix, use CROSS_PREFIX=
> -#   $ make CROSS_PREFIX=x86_64-linux-gnu-
> +#
> +# 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.
> +#
> +
> +TARGET_LIST = i386
> +
> +SRC_PATH = ../..
>
>  override define __note
> -/* This file is automatically generated from
> - * tests/migration/x86-a-b-bootblock.S, edit that and then run
> - * tests/migration/rebuild-x86-bootblock.sh to update,
> - * and then remember to send both in your patch submission.
> +/* This file is automatically generated from the assembly file in
> + * tests/migration/$@. Edit that file and then run "make all"
> + * inside tests/migration to update, and then remember to send both
> + * the header and the assembler differences in your patch submission.
>   */
>  endef
>  export __note
>
> -.PHONY: all clean
> -all: x86-a-b-bootblock.h
> -
> -x86-a-b-bootblock.h: x86.bootsect
> -	echo "$$__note" > header.tmp
> -	xxd -i $< | sed -e 's/.*int.*//' >> header.tmp
> -	mv header.tmp $@
> +find-arch-cross-cc = $(lastword $(shell grep -h "CROSS_CC_GUEST=" $(wildcard $(SRC_PATH)/$(patsubst i386,*86*,$(1))-softmmu/config-target.mak)))
> +parse-cross-prefix = $(subst gcc,,$(patsubst cc,gcc,$(patsubst CROSS_CC_GUEST="%",%,$(call find-arch-cross-cc,$(1)))))
> +gen-cross-prefix = $(patsubst %-,CROSS_PREFIX=%-,$(call
> parse-cross-prefix,$(1)))

This all seems awfully fiddly compared to moving the code to tests/tcg
and building with the existing machinery. You don't even get the docker
fall-back this way.

The aim being to have the ability to build the binary and manually
update the .hex/.S encoded version actually used in the test when you
don't have cross compilers available right?

I've got some TODOs in tests/tcg to start building the various system
tests. Perhaps I should port the various migration kernels when I get to
that?

>
> -x86.bootsect: x86.boot
> -	dd if=$< of=$@ bs=256 count=2 skip=124
> +.PHONY: all $(TARGET_LIST)
>
> -x86.boot: x86.o
> -	$(CROSS_PREFIX)objcopy -O binary $< $@
> +all: $(TARGET_LIST)
>
> -x86.o: x86-a-b-bootblock.S
> -	$(CROSS_PREFIX)gcc -m32 -march=i486 -c $< -o $@
> +$(TARGET_LIST):
> +	$(MAKE) -C $@ $(call gen-cross-prefix,$@)
>
>  clean:
> -	@rm -rf *.boot *.o *.bootsect
> +	for target in $(TARGET_LIST); do \
> +		$(MAKE) -C $$target clean; \
> +	done
> diff --git a/tests/migration/i386/Makefile b/tests/migration/i386/Makefile
> new file mode 100644
> index 0000000..5c03241
> --- /dev/null
> +++ b/tests/migration/i386/Makefile
> @@ -0,0 +1,22 @@
> +# To specify cross compiler prefix, use CROSS_PREFIX=
> +#   $ make CROSS_PREFIX=x86_64-linux-gnu-
> +
> +.PHONY: all clean
> +all: a-b-bootblock.h
> +
> +a-b-bootblock.h: x86.bootsect
> +	echo "$$__note" > header.tmp
> +	xxd -i $< | sed -e 's/.*int.*//' >> header.tmp
> +	mv header.tmp $@
> +
> +x86.bootsect: x86.boot
> +	dd if=$< of=$@ bs=256 count=2 skip=124
> +
> +x86.boot: x86.o
> +	$(CROSS_PREFIX)objcopy -O binary $< $@
> +
> +x86.o: a-b-bootblock.S
> +	$(CROSS_PREFIX)gcc -m32 -march=i486 -c $< -o $@
> +
> +clean:
> +	@rm -rf *.boot *.o *.bootsect
> diff --git a/tests/migration/x86-a-b-bootblock.S b/tests/migration/i386/a-b-bootblock.S
> similarity index 93%
> rename from tests/migration/x86-a-b-bootblock.S
> rename to tests/migration/i386/a-b-bootblock.S
> index b164264..3f97f28 100644
> --- a/tests/migration/x86-a-b-bootblock.S
> +++ b/tests/migration/i386/a-b-bootblock.S
> @@ -3,10 +3,6 @@
>  #  range.
>  #  Outputs an initial 'A' on serial followed by repeated 'B's
>  #
> -# run   tests/migration/rebuild-x86-bootblock.sh
> -#   to regenerate the hex, and remember to include both the .h and .s
> -#   in any patches.
> -#
>  # Copyright (c) 2016 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.
> diff --git a/tests/migration/x86-a-b-bootblock.h b/tests/migration/i386/a-b-bootblock.h
> similarity index 92%
> rename from tests/migration/x86-a-b-bootblock.h
> rename to tests/migration/i386/a-b-bootblock.h
> index 78a151f..7d459d4 100644
> --- a/tests/migration/x86-a-b-bootblock.h
> +++ b/tests/migration/i386/a-b-bootblock.h
> @@ -1,7 +1,7 @@
> -/* This file is automatically generated from
> - * tests/migration/x86-a-b-bootblock.s, edit that and then run
> - * tests/migration/rebuild-x86-bootblock.sh to update,
> - * and then remember to send both in your patch submission.
> +/* This file is automatically generated from the assembly file in
> + * tests/migration/i386. Edit that file and then run "make all"
> + * inside tests/migration to update, and then remember to send both
> + * the header and the assembler differences in your patch submission.
>   */
>  unsigned char x86_bootsect[] = {
>    0xfa, 0x0f, 0x01, 0x16, 0x74, 0x7c, 0x66, 0xb8, 0x01, 0x00, 0x00, 0x00,


--
Alex Bennée