[PATCH v4 0/3] reftable: graceful concurrent writes

Hi,

this is the fourth version of my patch series that implements for graceful concurrent writes with the reftable backend.

There's only a single change, namely a fix to the type used by the newly introduced `flags` field.

Thanks!

Patrick

Patrick Steinhardt (3):
  refs/reftable: introduce "reftable.lockTimeout"
  reftable/stack: allow locking of outdated stacks
  refs/reftable: reload locked stack when preparing transaction

 Documentation/config/reftable.txt |  8 ++++
 refs/reftable-backend.c           | 13 +++++-
 reftable/reftable-stack.h         | 13 +++++-
 reftable/reftable-writer.h        | 11 +++++
 reftable/stack.c                  | 38 ++++++++++++------
 t/t0610-reftable-basics.sh        | 58 ++++++++++++++++++++++++++
 t/unit-tests/t-reftable-stack.c   | 67 ++++++++++++++++++++++++++++++-
 7 files changed, 189 insertions(+), 19 deletions(-)

Range-diff against v3:
1:  77cffd3b1eb = 1:  77cffd3b1eb refs/reftable: introduce "reftable.lockTimeout"
2:  6130565498e ! 2:  81a836062e9 reftable/stack: allow locking of outdated stacks
    @@ reftable/reftable-stack.h: uint64_t reftable_stack_next_update_index(struct reft
      int reftable_stack_new_addition(struct reftable_addition **dest,
     -				struct reftable_stack *st);
     +				struct reftable_stack *st,
    -+				int flags);
    ++				unsigned int flags);
      
      /* Adds a reftable to transaction. */
      int reftable_addition_add(struct reftable_addition *add,
    @@ reftable/stack.c: struct reftable_addition {
      static int reftable_stack_init_addition(struct reftable_addition *add,
     -					struct reftable_stack *st)
     +					struct reftable_stack *st,
    -+					int flags)
    ++					unsigned int flags)
      {
      	struct strbuf lock_file_name = STRBUF_INIT;
      	int err;
    @@ reftable/stack.c: int reftable_addition_commit(struct reftable_addition *add)
      int reftable_stack_new_addition(struct reftable_addition **dest,
     -				struct reftable_stack *st)
     +				struct reftable_stack *st,
    -+				int flags)
    ++				unsigned int flags)
      {
      	int err = 0;
      	struct reftable_addition empty = REFTABLE_ADDITION_INIT;
3:  25d4e513a36 = 3:  9ce2d18dff2 refs/reftable: reload locked stack when preparing transaction