Re: [systemd-devel] [RFC] [PATCH 0/3] resume: implement support for resuming from hibernation
Hi Ivan, Great job! I was wondering if a ./configure switch makes sense to disable it. Embedded devices won't be using it. Thanks On Sat, Aug 23, 2014 at 2:47 PM, Ivan Shapovalov intelfx...@gmail.com wrote: This patchset allows systemd to parse resume= kernel command line parameter and initiate resume from the specified device. It adds: - a 'systemd-resume' tool which takes path to a device node and writes its major:minor to /sys/power/state; - a corresponding 'systemd-resume@.service' templated unit; - a 'systemd-resume-generator' generator which parses the kernel command line and instantiates the unit as necessary. This functionality already exists in-kernel, but only for /dev/sdXY-style pathes. Implementing it in userspace allows to use arbitrary udev-created symlinks, e. g. persistent block device pathes (/dev/disk/by-foo/bar). Userspace parsing of resume= kernel command line parameter has been traditionally done in initramfs via shell scripts (for Arch Linux, this is resume mkinitcpio hook), so I feel that this feature has its place within systemd. Due to the nature of hibernation, the resume unit must be activated before any modifications to filesystems take place. This can happen 1) in initramfs before mounting anything, and 2) without initramfs before remounting rootfs read-write (provided that it is mounted RO initially). So, first patch orders all non-root fsck after local-fs-pre.target, which in turn allows to order the resume unit before those fsck instances. Second and third patches add the tool, the unit and the generator. There are some issues with this implementation: - legacy usr.mount is not automatically ordered after local-fs-pre.target, so systemd-resume@.service has to be manually ordered before it; - systemd-udevd.service, which is needed for creating persistent block device symlinks, is transitively ordered after systemd-remount-fs.service via at least systemd-udev-hwdb-update.service and systemd-sysusers.service. Hence, if these units are present (at least initramfs-less case), an ordering cycle happens and resume is impossible. So, I would like someone to comment on these. This is my first patch to this project, so feel free to flak me for missing something obvious :) Thanks for reviewing! Ivan Shapovalov (3): units: order systemd-fsck@.service after local-fs-pre.target. resume: add a tool to write a device node's major:minor to /sys/power/resume. resume-generator: add a generator for instantiating the resume unit. Makefile-man.am | 9 Makefile.am | 28 -- man/kernel-command-line.xml | 13 - man/systemd-resume-generator.xml| 91 + man/systemd-res...@.service.xml | 81 + src/resume-generator/Makefile | 1 + src/resume-generator/resume-generator.c | 89 src/resume/Makefile | 1 + src/resume/resume.c | 82 + units/systemd-f...@.service.in | 2 +- units/systemd-res...@.service.in| 23 + 11 files changed, 414 insertions(+), 6 deletions(-) create mode 100644 man/systemd-resume-generator.xml create mode 100644 man/systemd-res...@.service.xml create mode 12 src/resume-generator/Makefile create mode 100644 src/resume-generator/resume-generator.c create mode 12 src/resume/Makefile create mode 100644 src/resume/resume.c create mode 100644 units/systemd-res...@.service.in -- 2.1.0 ___ systemd-devel mailing list systemd-devel@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/systemd-devel ___ systemd-devel mailing list systemd-devel@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/systemd-devel
Re: [systemd-devel] [RFC] [PATCH 0/3] resume: implement support for resuming from hibernation
On Wed, 27.08.14 10:19, Umut Tezduyar Lindskog (u...@tezduyar.com) wrote: Hi Ivan, Great job! I was wondering if a ./configure switch makes sense to disable it. Embedded devices won't be using it. Sure! I'd be happy to merge a patch that makes this compile-time optional. Lennart -- Lennart Poettering, Red Hat ___ systemd-devel mailing list systemd-devel@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/systemd-devel
[systemd-devel] [RFC] [PATCH 0/3] resume: implement support for resuming from hibernation
This patchset allows systemd to parse resume= kernel command line parameter and initiate resume from the specified device. It adds: - a 'systemd-resume' tool which takes path to a device node and writes its major:minor to /sys/power/state; - a corresponding 'systemd-resume@.service' templated unit; - a 'systemd-resume-generator' generator which parses the kernel command line and instantiates the unit as necessary. This functionality already exists in-kernel, but only for /dev/sdXY-style pathes. Implementing it in userspace allows to use arbitrary udev-created symlinks, e. g. persistent block device pathes (/dev/disk/by-foo/bar). Userspace parsing of resume= kernel command line parameter has been traditionally done in initramfs via shell scripts (for Arch Linux, this is resume mkinitcpio hook), so I feel that this feature has its place within systemd. Due to the nature of hibernation, the resume unit must be activated before any modifications to filesystems take place. This can happen 1) in initramfs before mounting anything, and 2) without initramfs before remounting rootfs read-write (provided that it is mounted RO initially). So, first patch orders all non-root fsck after local-fs-pre.target, which in turn allows to order the resume unit before those fsck instances. Second and third patches add the tool, the unit and the generator. There are some issues with this implementation: - legacy usr.mount is not automatically ordered after local-fs-pre.target, so systemd-resume@.service has to be manually ordered before it; - systemd-udevd.service, which is needed for creating persistent block device symlinks, is transitively ordered after systemd-remount-fs.service via at least systemd-udev-hwdb-update.service and systemd-sysusers.service. Hence, if these units are present (at least initramfs-less case), an ordering cycle happens and resume is impossible. So, I would like someone to comment on these. This is my first patch to this project, so feel free to flak me for missing something obvious :) Thanks for reviewing! Ivan Shapovalov (3): units: order systemd-fsck@.service after local-fs-pre.target. resume: add a tool to write a device node's major:minor to /sys/power/resume. resume-generator: add a generator for instantiating the resume unit. Makefile-man.am | 9 Makefile.am | 28 -- man/kernel-command-line.xml | 13 - man/systemd-resume-generator.xml| 91 + man/systemd-res...@.service.xml | 81 + src/resume-generator/Makefile | 1 + src/resume-generator/resume-generator.c | 89 src/resume/Makefile | 1 + src/resume/resume.c | 82 + units/systemd-f...@.service.in | 2 +- units/systemd-res...@.service.in| 23 + 11 files changed, 414 insertions(+), 6 deletions(-) create mode 100644 man/systemd-resume-generator.xml create mode 100644 man/systemd-res...@.service.xml create mode 12 src/resume-generator/Makefile create mode 100644 src/resume-generator/resume-generator.c create mode 12 src/resume/Makefile create mode 100644 src/resume/resume.c create mode 100644 units/systemd-res...@.service.in -- 2.1.0 ___ systemd-devel mailing list systemd-devel@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/systemd-devel
Re: [systemd-devel] [RFC] [PATCH 0/3] resume: implement support for resuming from hibernation
В Sat, 23 Aug 2014 16:47:51 +0400 Ivan Shapovalov intelfx...@gmail.com пишет: This patchset allows systemd to parse resume= kernel command line parameter and initiate resume from the specified device. It adds: - a 'systemd-resume' tool which takes path to a device node and writes its major:minor to /sys/power/state; - a corresponding 'systemd-resume@.service' templated unit; - a 'systemd-resume-generator' generator which parses the kernel command line and instantiates the unit as necessary. This functionality already exists in-kernel, but only for /dev/sdXY-style pathes. Implementing it in userspace allows to use arbitrary udev-created symlinks, e. g. persistent block device pathes (/dev/disk/by-foo/bar). Userspace parsing of resume= kernel command line parameter has been traditionally done in initramfs via shell scripts (for Arch Linux, this is resume mkinitcpio hook), so I feel that this feature has its place within systemd. Due to the nature of hibernation, the resume unit must be activated before any modifications to filesystems take place. This can happen 1) in initramfs before mounting anything, and 2) without initramfs before remounting rootfs read-write (provided that it is mounted RO initially). Your patch has +ConditionPathExists=|/etc/initrd-release Which excludes non-initrd usage, right? Also some filesystems (reiserfs comes in mind) replayed journal even when mounted read-only. So may be it should explicitly state initrd-only support and name units accordingly. So, first patch orders all non-root fsck after local-fs-pre.target, which in turn allows to order the resume unit before those fsck instances. Second and third patches add the tool, the unit and the generator. There are some issues with this implementation: - legacy usr.mount is not automatically ordered after local-fs-pre.target, so systemd-resume@.service has to be manually ordered before it; - systemd-udevd.service, which is needed for creating persistent block device symlinks, is transitively ordered after systemd-remount-fs.service via at least systemd-udev-hwdb-update.service and systemd-sysusers.service. Hence, if these units are present (at least initramfs-less case), an ordering cycle happens and resume is impossible. So, I would like someone to comment on these. This is my first patch to this project, so feel free to flak me for missing something obvious :) Thanks for reviewing! Ivan Shapovalov (3): units: order systemd-fsck@.service after local-fs-pre.target. resume: add a tool to write a device node's major:minor to /sys/power/resume. resume-generator: add a generator for instantiating the resume unit. Makefile-man.am | 9 Makefile.am | 28 -- man/kernel-command-line.xml | 13 - man/systemd-resume-generator.xml| 91 + man/systemd-res...@.service.xml | 81 + src/resume-generator/Makefile | 1 + src/resume-generator/resume-generator.c | 89 src/resume/Makefile | 1 + src/resume/resume.c | 82 + units/systemd-f...@.service.in | 2 +- units/systemd-res...@.service.in| 23 + 11 files changed, 414 insertions(+), 6 deletions(-) create mode 100644 man/systemd-resume-generator.xml create mode 100644 man/systemd-res...@.service.xml create mode 12 src/resume-generator/Makefile create mode 100644 src/resume-generator/resume-generator.c create mode 12 src/resume/Makefile create mode 100644 src/resume/resume.c create mode 100644 units/systemd-res...@.service.in ___ systemd-devel mailing list systemd-devel@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/systemd-devel
Re: [systemd-devel] [RFC] [PATCH 0/3] resume: implement support for resuming from hibernation
On Saturday 23 August 2014 at 18:22:42, Andrei Borzenkov wrote: В Sat, 23 Aug 2014 16:47:51 +0400 Ivan Shapovalov intelfx...@gmail.com пишет: This patchset allows systemd to parse resume= kernel command line parameter and initiate resume from the specified device. It adds: - a 'systemd-resume' tool which takes path to a device node and writes its major:minor to /sys/power/state; - a corresponding 'systemd-resume@.service' templated unit; - a 'systemd-resume-generator' generator which parses the kernel command line and instantiates the unit as necessary. This functionality already exists in-kernel, but only for /dev/sdXY-style pathes. Implementing it in userspace allows to use arbitrary udev-created symlinks, e. g. persistent block device pathes (/dev/disk/by-foo/bar). Userspace parsing of resume= kernel command line parameter has been traditionally done in initramfs via shell scripts (for Arch Linux, this is resume mkinitcpio hook), so I feel that this feature has its place within systemd. Due to the nature of hibernation, the resume unit must be activated before any modifications to filesystems take place. This can happen 1) in initramfs before mounting anything, and 2) without initramfs before remounting rootfs read-write (provided that it is mounted RO initially). Your patch has +ConditionPathExists=|/etc/initrd-release Which excludes non-initrd usage, right? Also some filesystems (reiserfs comes in mind) replayed journal even when mounted read-only. So may be it should explicitly state initrd-only support and name units accordingly. It doesn't exclude non-initramfs image -- there is a second OR-ed conditional allowing this unit to run on a ro-mounted real root. I didn't know that reiserfs can write to a ro-mounted fs. If that's true, non-initramfs usage must be prohibited. I'll send a v2. Thanks for pointing that out! -- Ivan Shapovalov / intelfx / signature.asc Description: This is a digitally signed message part. ___ systemd-devel mailing list systemd-devel@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/systemd-devel
Re: [systemd-devel] [RFC] [PATCH 0/3] resume: implement support for resuming from hibernation
On 23 August 2014 14:47, Ivan Shapovalov intelfx...@gmail.com wrote: This is my first patch to this project, so feel free to flak me for missing something obvious :) On 4 August 2014 10:39, Tobias Geerinckx-Rice tobias.geerinckx.r...@gmail.com wrote: (As this is my first systemd patch, feel free to flak me for missing something obvious.) http://media.tumblr.com/tumblr_lpn8viK7f61qc4jgq.jpg On a more serious note: thanks for pursuing this; I hope it makes it into git soon! Regards, T G-R ___ systemd-devel mailing list systemd-devel@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/systemd-devel
Re: [systemd-devel] [RFC] [PATCH 0/3] resume: implement support for resuming from hibernation
On Saturday 23 August 2014 at 21:05:13, Tobias Geerinckx-Rice wrote: On 23 August 2014 14:47, Ivan Shapovalov intelfx...@gmail.com wrote: This is my first patch to this project, so feel free to flak me for missing something obvious :) On 4 August 2014 10:39, Tobias Geerinckx-Rice tobias.geerinckx.r...@gmail.com wrote: (As this is my first systemd patch, feel free to flak me for missing something obvious.) http://media.tumblr.com/tumblr_lpn8viK7f61qc4jgq.jpg On a more serious note: thanks for pursuing this; I hope it makes it into git soon! I was just struggling to recall where have I seen this phrase :) Well, sorry for stealing, but it exactly describes my feeling about this. -- Ivan Shapovalov / intelfx / signature.asc Description: This is a digitally signed message part. ___ systemd-devel mailing list systemd-devel@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/systemd-devel
