[v2,00/11] grep: improve threading and fix race conditions

Message

Matheus Tavares Sept. 30, 2019, 1:50 a.m. UTC

This series focus on re-enabling threads at git-grep for the
non-worktree case. They are currently disabled due to being slower than
single-threaded grep in this case. However, by allowing parallel zlib
inflation when reading objects, speedups of up to 3x were observed.

The patchset also contains some fixes for race conditions found in the
worktree git-grep and thread optimizations to hopefully increase
overall performance.

This version was almost entirely re-written from scratch so I thought a
range-diff wouldn't be very useful. The major differences from the first
one are the race condition fixes and being able to run --textconv and
--recurse-submodules threaded now.

Matheus Tavares (11):
  grep: fix race conditions on userdiff calls
  grep: fix race conditions at grep_submodule()
  grep: fix racy calls in grep_objects()
  replace-object: make replace operations thread-safe
  object-store: allow threaded access to object reading
  grep: replace grep_read_mutex by internal obj read lock
  submodule-config: add skip_if_read option to repo_read_gitmodules()
  grep: allow submodule functions to run in parallel
  grep: protect packed_git [re-]initialization
  grep: re-enable threads in non-worktree case
  grep: move driver pre-load out of critical section

 .tsan-suppressions         |  6 +++
 Documentation/git-grep.txt | 11 +++++
 builtin/grep.c             | 90 +++++++++++++++++++-------------------
 grep.c                     | 32 ++++++++------
 grep.h                     | 13 ------
 object-store.h             | 37 ++++++++++++++++
 object.c                   |  2 +
 packfile.c                 |  9 ++++
 replace-object.c           | 11 ++++-
 replace-object.h           |  7 ++-
 sha1-file.c                | 57 +++++++++++++++++++++---
 submodule-config.c         | 18 +++-----
 submodule-config.h         |  2 +-
 unpack-trees.c             |  4 +-
 14 files changed, 205 insertions(+), 94 deletions(-)