[petsc-dev] git help needed

[Barry Smith]

  I accidentally added and committed in master when I meant to do it in another branch. 

~/Src/petsc/src/ts/examples/tutorials  master $ git add ex1s.c
~/Src/petsc/src/ts/examples/tutorials  master $ git commit -a
[master 8bd0fc5] adding SNESPSEUDO solver
 5 files changed, 449 insertions(+), 1 deletion(-)
 create mode 100644 src/ts/examples/tutorials/ex1s.c

How do I undo this so I can switch to another branch and do the commits into that?

git revert help message is useless