ARM /proc/cpu/alignment with systemd images in dora

ARM /proc/cpu/alignment with systemd images in dora

[Holger Hans Peter Freyther]

Good Evening,

I noticed that the "alignment.sh" is not ran on my systemd images. I
think I opened a bug about systemd ignoring ".sh" scripts but that was
fixed and also not the main issue here. After looking at src/core/service.c
of systemd the rcS.d is not looked at.

Can something like the below be included? This will start the alignment
in runlevel2 too and will then be executed by systemd. Alternatively one
could add a proper symlink for the alignment target inside the systemd
recipe?

Comments?

diff --git a/meta/recipes-core/initscripts/initscripts_1.0.bb b/meta/recipes-core/initscripts/initscripts_1.0.bb
index 50ebb1c..08539a2 100644
--- a/meta/recipes-core/initscripts/initscripts_1.0.bb
+++ b/meta/recipes-core/initscripts/initscripts_1.0.bb
@@ -124,7 +124,7 @@ do_install () {
        update-rc.d -r ${D} read-only-rootfs-hook.sh start 29 S .
        update-rc.d -r ${D} devpts.sh start 38 S .
        if [ "${TARGET_ARCH}" = "arm" ]; then
-               update-rc.d -r ${D} alignment.sh start 06 S .
+               update-rc.d -r ${D} alignment.sh start 06 S 2 .
        fi
        # We wish to have /var/log ready at this stage so execute this after
        # populate-volatile.sh

Re: ARM /proc/cpu/alignment with systemd images in dora

[Mehaffey, John]

> From: poky-bounces@yoctoproject.org [mailto:poky-bounces@yoctoproject.org] On Behalf Of Holger Hans Peter Freyther
> Sent: Monday, March 31, 2014 1:58 PM
> To: poky@yoctoproject.org
> Subject: [poky] ARM /proc/cpu/alignment with systemd images in dora
> 
> Good Evening,
> 
> I noticed that the "alignment.sh" is not ran on my systemd images. I think I opened a bug about systemd ignoring ".sh" scripts but that was fixed and also not the main issue here. After looking at src/core/service.c of systemd the rcS.d is not looked at.
> 
> Can something like the below be included? This will start the alignment in runlevel2 too and will then be executed by systemd. Alternatively one could add a proper symlink for the alignment target inside the systemd recipe?
> 
> Comments?
> 
> diff --git a/meta/recipes-core/initscripts/initscripts_1.0.bb b/meta/recipes-core/initscripts/initscripts_1.0.bb
> index 50ebb1c..08539a2 100644
> --- a/meta/recipes-core/initscripts/initscripts_1.0.bb
> +++ b/meta/recipes-core/initscripts/initscripts_1.0.bb
> @@ -124,7 +124,7 @@ do_install () {
>         update-rc.d -r ${D} read-only-rootfs-hook.sh start 29 S .
>         update-rc.d -r ${D} devpts.sh start 38 S .
>         if [ "${TARGET_ARCH}" = "arm" ]; then
> -               update-rc.d -r ${D} alignment.sh start 06 S .
> +               update-rc.d -r ${D} alignment.sh start 06 S 2 .
>         fi
>         # We wish to have /var/log ready at this stage so execute this after
>         # populate-volatile.sh

Hi Holger,

The proper way to integrate this into systemd is to create a unit file. What must be run before alignment.sh? what things depend on it?
Then depend on it from the proper targets. 

The workaround you suggest runs the risk of incorrect ordering as things migrate from SysV init.

-mehaf

Re: ARM /proc/cpu/alignment with systemd images in dora

[Holger Hans Peter Freyther]

On Mon, Mar 31, 2014 at 10:15:58PM +0000, Mehaffey, John wrote:

Hi John,

> The proper way to integrate this into systemd is to create a unit file. What must be run before alignment.sh? what things depend on it?
> Then depend on it from the proper targets. 
> 
> The workaround you suggest runs the risk of incorrect ordering as things migrate from SysV init.

one can easily argue about what is the "proper" way. The "default" with
systemd images on a ARMv5 is that unaligned memory access will be ignored
while it used to be fixed-up.

Is this considered a regression by the OE-core/Poky developers? For
this image generation of our BTS images we are using the patch I have
proposed. Creating a cpu-alignment.service is not a priority for us
right now.


cheers
	holger