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diff --git a/Documentation/howto/using-topic-branches.txt b/Documentation/howto/using-topic-branches.txt deleted file mode 100644 index 2c98194cb..000000000 --- a/Documentation/howto/using-topic-branches.txt +++ /dev/null @@ -1,296 +0,0 @@ -Date: Mon, 15 Aug 2005 12:17:41 -0700 -From: tony.luck@intel.com -Subject: Some tutorial text (was git/cogito workshop/bof at linuxconf au?) -Abstract: In this article, Tony Luck discusses how he uses GIT - as a Linux subsystem maintainer. - -Here's something that I've been putting together on how I'm using -GIT as a Linux subsystem maintainer. - --Tony - -Last updated w.r.t. GIT 1.1 - -Linux subsystem maintenance using GIT -------------------------------------- - -My requirements here are to be able to create two public trees: - -1) A "test" tree into which patches are initially placed so that they -can get some exposure when integrated with other ongoing development. -This tree is available to Andrew for pulling into -mm whenever he wants. - -2) A "release" tree into which tested patches are moved for final -sanity checking, and as a vehicle to send them upstream to Linus -(by sending him a "please pull" request.) - -Note that the period of time that each patch spends in the "test" tree -is dependent on the complexity of the change. Since GIT does not support -cherry picking, it is not practical to simply apply all patches to the -test tree and then pull to the release tree as that would leave trivial -patches blocked in the test tree waiting for complex changes to accumulate -enough test time to graduate. - -Back in the BitKeeper days I achieved this by creating small forests of -temporary trees, one tree for each logical grouping of patches, and then -pulling changes from these trees first to the test tree, and then to the -release tree. At first I replicated this in GIT, but then I realised -that I could so this far more efficiently using branches inside a single -GIT repository. - -So here is the step-by-step guide how this all works for me. - -First create your work tree by cloning Linus's public tree: - - $ git clone git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6.git work - -Change directory into the cloned tree you just created - - $ cd work - -Set up a remotes file so that you can fetch the latest from Linus' master -branch into a local branch named "linus": - - $ cat > .git/remotes/linus - URL: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6.git - Pull: master:linus - ^D - -and create the linus branch: - - $ git branch linus - -The "linus" branch will be used to track the upstream kernel. To update it, -you simply run: - - $ git fetch linus - -you can do this frequently (and it should be safe to do so with pending -work in your tree, but perhaps not if you are in mid-merge). - -If you need to keep track of other public trees, you can add remote branches -for them too: - - $ git branch another - $ cat > .git/remotes/another - URL: ... insert URL here ... - Pull: name-of-branch-in-this-remote-tree:another - ^D - -and run: - - $ git fetch another - -Now create the branches in which you are going to work, these start -out at the current tip of the linus branch. - - $ git branch test linus - $ git branch release linus - -These can be easily kept up to date by merging from the "linus" branch: - - $ git checkout test && git merge "Auto-update from upstream" test linus - $ git checkout release && git merge "Auto-update from upstream" release linus - -Important note! If you have any local changes in these branches, then -this merge will create a commit object in the history (with no local -changes git will simply do a "Fast forward" merge). Many people dislike -the "noise" that this creates in the Linux history, so you should avoid -doing this capriciously in the "release" branch, as these noisy commits -will become part of the permanent history when you ask Linus to pull -from the release branch. - -Set up so that you can push upstream to your public tree (you need to -log-in to the remote system and create an empty tree there before the -first push). - - $ cat > .git/remotes/mytree - URL: master.kernel.org:/pub/scm/linux/kernel/git/aegl/linux-2.6.git - Push: release - Push: test - ^D - -and the push both the test and release trees using: - - $ git push mytree - -or push just one of the test and release branches using: - - $ git push mytree test -or - $ git push mytree release - -Now to apply some patches from the community. Think of a short -snappy name for a branch to hold this patch (or related group of -patches), and create a new branch from the current tip of the -linus branch: - - $ git checkout -b speed-up-spinlocks linus - -Now you apply the patch(es), run some tests, and commit the change(s). If -the patch is a multi-part series, then you should apply each as a separate -commit to this branch. - - $ ... patch ... test ... commit [ ... patch ... test ... commit ]* - -When you are happy with the state of this change, you can pull it into the -"test" branch in preparation to make it public: - - $ git checkout test && git merge "Pull speed-up-spinlock changes" test speed-up-spinlocks - -It is unlikely that you would have any conflicts here ... but you might if you -spent a while on this step and had also pulled new versions from upstream. - -Some time later when enough time has passed and testing done, you can pull the -same branch into the "release" tree ready to go upstream. This is where you -see the value of keeping each patch (or patch series) in its own branch. It -means that the patches can be moved into the "release" tree in any order. - - $ git checkout release && git merge "Pull speed-up-spinlock changes" release speed-up-spinlocks - -After a while, you will have a number of branches, and despite the -well chosen names you picked for each of them, you may forget what -they are for, or what status they are in. To get a reminder of what -changes are in a specific branch, use: - - $ git-whatchanged branchname ^linus | git-shortlog - -To see whether it has already been merged into the test or release branches -use: - - $ git-rev-list branchname ^test -or - $ git-rev-list branchname ^release - -[If this branch has not yet been merged you will see a set of SHA1 values -for the commits, if it has been merged, then there will be no output] - -Once a patch completes the great cycle (moving from test to release, then -pulled by Linus, and finally coming back into your local "linus" branch) -the branch for this change is no longer needed. You detect this when the -output from: - - $ git-rev-list branchname ^linus - -is empty. At this point the branch can be deleted: - - $ git branch -d branchname - -Some changes are so trivial that it is not necessary to create a separate -branch and then merge into each of the test and release branches. For -these changes, just apply directly to the "release" branch, and then -merge that into the "test" branch. - -To create diffstat and shortlog summaries of changes to include in a "please -pull" request to Linus you can use: - - $ git-whatchanged -p release ^linus | diffstat -p1 -and - $ git-whatchanged release ^linus | git-shortlog - - -Here are some of the scripts that I use to simplify all this even further. - -==== update script ==== -# Update a branch in my GIT tree. If the branch to be updated -# is "linus", then pull from kernel.org. Otherwise merge local -# linus branch into test|release branch - -case "$1" in -test|release) - git checkout $1 && git merge "Auto-update from upstream" $1 linus - ;; -linus) - before=$(cat .git/refs/heads/linus) - git fetch linus - after=$(cat .git/refs/heads/linus) - if [ $before != $after ] - then - git-whatchanged $after ^$before | git-shortlog - fi - ;; -*) - echo "Usage: $0 linus|test|release" 1>&2 - exit 1 - ;; -esac - -==== merge script ==== -# Merge a branch into either the test or release branch - -pname=$0 - -usage() -{ - echo "Usage: $pname branch test|release" 1>&2 - exit 1 -} - -if [ ! -f .git/refs/heads/"$1" ] -then - echo "Can't see branch <$1>" 1>&2 - usage -fi - -case "$2" in -test|release) - if [ $(git-rev-list $1 ^$2 | wc -c) -eq 0 ] - then - echo $1 already merged into $2 1>&2 - exit 1 - fi - git checkout $2 && git merge "Pull $1 into $2 branch" $2 $1 - ;; -*) - usage - ;; -esac - -==== status script ==== -# report on status of my ia64 GIT tree - -gb=$(tput setab 2) -rb=$(tput setab 1) -restore=$(tput setab 9) - -if [ `git-rev-list release ^test | wc -c` -gt 0 ] -then - echo $rb Warning: commits in release that are not in test $restore - git-whatchanged release ^test -fi - -for branch in `ls .git/refs/heads` -do - if [ $branch = linus -o $branch = test -o $branch = release ] - then - continue - fi - - echo -n $gb ======= $branch ====== $restore " " - status= - for ref in test release linus - do - if [ `git-rev-list $branch ^$ref | wc -c` -gt 0 ] - then - status=$status${ref:0:1} - fi - done - case $status in - trl) - echo $rb Need to pull into test $restore - ;; - rl) - echo "In test" - ;; - l) - echo "Waiting for linus" - ;; - "") - echo $rb All done $restore - ;; - *) - echo $rb "<$status>" $restore - ;; - esac - git-whatchanged $branch ^linus | git-shortlog -done |