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  1. Jul 25, 2015
  2. Dec 31, 2014
    • Sebastian Andrzej Siewior's avatar
      [ANNOUNCE] 4.1.2-rt1 · 96f1ac50
      Sebastian Andrzej Siewior authored
      Dear RT folks!
      
      I'm pleased to announce the v4.1.2-rt1 patch set.
      
      The move from 4.0 to 4.1 was rather smooth, so we took the time for
      some overdue cleanups and restructuring of the patch queue.
      
      1) Patch folding
      
         - Fold all fixlets into the proper patches
      
         - Consolidate the patches which change the same piece of code over
           and over (e.g. add/revert/redo).
      
         These patches were mostly kept to be easily picked up for stable.
      
      2) Dropping obsolete patches
      
         Some patches have been superseeded by different upstream changes,
         so the RT variant is redundant.
      
      3) Changelogs
      
         Quite some patches had no or useless changelogs. We updated them
         all. Each patch has now a From+Subject+Date field. That means "git
         quiltimport" will produce now the same commit id for each patch (as
         long as the commit author and date remain unchanged).
      
      4) Reordering
      
         The patches got reordered in topics, so patches related to the same
         subsystem or problem space are grouped together.
      
      5) Ability to build and boot
      
         Each step in the queue now builds with RT=n and RT=y. All steps
         boot with RT=n. With RT=y the functionality is obviously dependent
         on all patches, so a boot bisectability can not be achieved.
      
      As of now we provide a git tree with the RT changes as well. The tree
      is similar structured as Stevens stable RT tree. For each kernel
      version we provide 3 branches:
      
       linux-m.n.y-rt
      
      	This branch starts when we move to a new kernel version. After
      	the first release this branch gets only incremental updates
      	(either from the mainline stable tree or from updates to the
      	rt patch queue)
      
       linux-m.n.y-rt-rebase
      
      	This branch is rebased when a new stable version or a new RT
      	patch queue is available. The RT patch queue is applied on top
      	of the latest mainline stable version.
      
       linux-m.n.y-queue
      
      	This branch contains the revisions of the rt patch queue -
      	patches and series file.
      
      Known issues:
      
      - My AMD box throws a lot of "cpufreq_stat_notifier_trans: No
        policy found" warnings after boot. It is gone after manually
        setting the policy (to something else than reported).
      
      - bcache is disabled.
      
      - CPU hotplug works in general. Steven's test script however
        deadlocks usually on the second invocation.
      
      - xor / raid_pq
        I had max latency jumping up to 67563us on one CPU while the next
        lower max was 58us. I tracked it down to module's init code of
        xor and raid_pq. Both disable preemption while measuring the
        performance of the individual implementation.
      
      The git URLs for this release are
      
          git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt
          git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt-rebase
          git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt-queue
      
      The RT patch against 4.1.2 can be found here:
      
          https://www.kernel.org/pub/linux/kernel/projects/rt/4.1/patch-4.1.2-rt1.patch.xz
      
      The split quilt queue is available at:
      
          https://www.kernel.org/pub/linux/kernel/projects/rt/4.1/patches-4.1.2-rt1.tar.xz
      
      
      
      Sebastian
      
      Signed-off-by: default avatarSebastian Andrzej Siewior <bigeasy@linutronix.de>