On Wed, Feb 13, 2013 at 05:17:44PM +0100, Igor Mammedov wrote:
> qemu boots from disk image 3 times faster than direct kernel load.
That's surprising. Do you have any idea why that happens?
(CCing qemu-devel in case other QEMU developers can explain it)
> Use grub2-mkrescue tool to create boot image with test kernel if available
> and do image boot then.
> On FC17 it reduces 1 VM run from ~15 sec to ~5sec.
>
> Signed-off-by: Igor Mammedov <imamm...@redhat.com>
> ---
> qemu/tests/cpuid.py | 11 +++++++++--
> shared/deps/cpuid_test_kernel/Makefile | 18 ++++++++++++++++--
> shared/deps/cpuid_test_kernel/grub.cfg | 8 ++++++++
> 3 files changed, 33 insertions(+), 4 deletions(-)
> create mode 100644 shared/deps/cpuid_test_kernel/grub.cfg
>
> diff --git a/qemu/tests/cpuid.py b/qemu/tests/cpuid.py
> index 5065c6a..731411c 100644
> --- a/qemu/tests/cpuid.py
> +++ b/qemu/tests/cpuid.py
> @@ -118,13 +118,20 @@ def run_cpuid(test, params, env):
> "cpuid_test_kernel")
> os.chdir(test_kernel_dir)
> utils.make("cpuid_dump_kernel.bin")
> + utils.make("boot.img", ignore_status=True)
> + cmdres = utils.run("cd %s && ls boot.img" % test_kernel_dir,
> ignore_status=True)
Why fork a shell just to check if a file exists? You can simply use
"os.path.exists('%s/boot.img' % (test_kernel_dir))" or
"os.path.exists(os.path.join(test_kernel_dir, 'boot.img'))".
The rest of the patch looks good to me.
I wonder if we could make this a generic "boot kernel image" function,
that uses grub2-mkrescue if available, and -kernel otherwise. I believe
other test cases may benefit for a general mechanism to boot test
kernels.
>
> vm_name = params.get('main_vm')
> params_b = params.copy()
> - params_b["kernel"] = os.path.join(test_kernel_dir,
> "cpuid_dump_kernel.bin")
> + if cmdres.exit_status == 0:
> + params_b["image_name_custom"] = os.path.join(test_kernel_dir,
> "boot.img")
> + params_b["image_format_custom"] = ""
> + params_b["images"] = "custom"
> + else:
> + params_b["kernel"] = os.path.join(test_kernel_dir,
> "cpuid_dump_kernel.bin")
> + del params_b["images"]
> params_b["cpu_model"] = cpu_model
> params_b["cpu_model_flags"] = feature
> - del params_b["images"]
> del params_b["nics"]
> env_process.preprocess_vm(self, params_b, env, vm_name)
> vm = env.get_vm(vm_name)
> diff --git a/shared/deps/cpuid_test_kernel/Makefile
> b/shared/deps/cpuid_test_kernel/Makefile
> index 0e34c43..5999804 100644
> --- a/shared/deps/cpuid_test_kernel/Makefile
> +++ b/shared/deps/cpuid_test_kernel/Makefile
> @@ -1,10 +1,24 @@
> CFLAGS := -m32 -fno-stack-protector -fno-builtin -nostdinc -O -g -Wall -I.
> LDFLAGS := -nostdlib -Wl,-N -Wl,-Ttext -Wl,100000
>
> -all: cpuid_dump_kernel.bin
> +boot := $(shell sh -c 'which grub2-mkrescue 2>/dev/null && echo
> grub2boot.img')
> +
> +all: cpuid_dump_kernel.bin boot.img
>
> cpuid_dump_kernel.bin: boot.S main.c test.c
> $(CC) -o $@ $(CFLAGS) $^ $(LDFLAGS)
> + ln -s $@ kernel.bin
> +
> +boot.img: $(boot)
> +
> +
> +grub2boot.img:
> + mkdir -p iso/boot/grub
> + cp -f grub.cfg iso/boot/grub
> + cp -f kernel.bin iso/
> + grub2-mkrescue -o boot.img iso
>
> clean:
> - rm -f *.o *.bin
> + rm -rf *.o *.bin iso *.img
> +
> +.PHONY: grub2boot.img
> diff --git a/shared/deps/cpuid_test_kernel/grub.cfg
> b/shared/deps/cpuid_test_kernel/grub.cfg
> new file mode 100644
> index 0000000..aeb5b2b
> --- /dev/null
> +++ b/shared/deps/cpuid_test_kernel/grub.cfg
> @@ -0,0 +1,8 @@
> +set timeout=0
> +set default=0
> +
> +menuentry "test" {
> + set root=(hd0)
> + multiboot /kernel.bin
> + boot
> +}
> --
> 1.7.1
>
--
Eduardo
