git/pack-objects.h, branch v2.23.2

pack-objects: convert packlist_find() to use object_id

2019-06-20T16:54:58Z

We take a raw hash pointer, but most of our callers have a "struct object_id" already. Let's switch to taking the full struct, which will let us continue removing uses of raw sha1 buffers. There are two callers that do need special attention: - in rebuild_existing_bitmaps(), we need to switch to nth_packed_object_oid(). This incurs an extra hash copy over pointing straight to the mmap'd sha1, but it shouldn't be measurable compared to the rest of the operation. - in can_reuse_delta() we already spent the effort to copy the sha1 into a "struct object_id", but now we just have to do so a little earlier in the function (we can't easily convert that function's callers because they may be pointing at mmap'd REF_DELTA blocks). Signed-off-by: Jeff King Signed-off-by: Junio C Hamano

pack-objects: drop unused parameter from oe_map_new_pack()

2019-02-14T23:26:15Z

Since 43fa44fa3b (pack-objects: move in_pack out of struct object_entry, 2018-04-14), we store the source pack for each object as a small index rather than as a pointer. When we see a new pack that has no allocated index, we fall back to generating an array of pointers by calling oe_map_new_pack(). Perhaps counter-intuitively, that function does not need to actually see our new index-less pack. It only allocates and populates the array with the existing packs, after which oe_set_in_pack() actually adds the new pack to the array. Let's drop the unused "struct packed_git" argument to oe_map_new_pack() to avoid confusion. Signed-off-by: Jeff King Signed-off-by: Junio C Hamano

Merge branch 'ph/pack-objects-mutex-fix'

2019-02-05T22:26:16Z

"git pack-objects" incorrectly used uninitialized mutex, which has been corrected. * ph/pack-objects-mutex-fix: pack-objects: merge read_lock and lock in packing_data struct pack-objects: move read mutex to packing_data struct

pack-objects: merge read_lock and lock in packing_data struct

2019-01-28T19:22:12Z

Rename the packing_data lock to obd_lock and upgrade it to a recursive mutex to make it suitable for current read_lock usages. Additionally remove the superfluous #ifndef NO_PTHREADS guard around mutex initialization in prepare_packing_data as the mutex functions themselves are already protected. Signed-off-by: Patrick Hogg Helped-by: Junio C Hamano Signed-off-by: Junio C Hamano

pack-objects: move read mutex to packing_data struct

2019-01-28T19:22:06Z

ac77d0c37 ("pack-objects: shrink size field in struct object_entry", 2018-04-14) added an extra usage of read_lock/read_unlock in the newly introduced oe_get_size_slow for thread safety in parallel calls to try_delta(). Unfortunately oe_get_size_slow is also used in serial code, some of which is called before the first invocation of ll_find_deltas. As such the read mutex is not guaranteed to be initialized. Resolve this by moving the read mutex to packing_data and initializing it in prepare_packing_data which is initialized in cmd_pack_objects. Signed-off-by: Patrick Hogg Reviewed-by: Duy Nguyen Signed-off-by: Junio C Hamano

Merge branch 'nd/the-index'

2019-01-04T21:33:33Z

More codepaths become aware of working with in-core repository instance other than the default "the_repository". * nd/the-index: (22 commits) rebase-interactive.c: remove the_repository references rerere.c: remove the_repository references pack-*.c: remove the_repository references pack-check.c: remove the_repository references notes-cache.c: remove the_repository references line-log.c: remove the_repository reference diff-lib.c: remove the_repository references delta-islands.c: remove the_repository references cache-tree.c: remove the_repository references bundle.c: remove the_repository references branch.c: remove the_repository reference bisect.c: remove the_repository reference blame.c: remove implicit dependency the_repository sequencer.c: remove implicit dependency on the_repository sequencer.c: remove implicit dependency on the_index transport.c: remove implicit dependency on the_index notes-merge.c: remove implicit dependency the_repository notes-merge.c: remove implicit dependency on the_index list-objects.c: reduce the_repository references list-objects-filter.c: remove implicit dependency on the_index ...

Merge branch 'cc/delta-islands'

2018-11-21T11:39:02Z

A few issues in the implementation of "delta-islands" feature has been corrected. * cc/delta-islands: pack-objects: fix off-by-one in delta-island tree-depth computation pack-objects: zero-initialize tree_depth/layer arrays pack-objects: fix tree_depth and layer invariants

pack-objects: zero-initialize tree_depth/layer arrays

2018-11-21T04:50:27Z

Commit 108f530385 (pack-objects: move tree_depth into 'struct packing_data', 2018-08-16) started maintaining a tree_depth array that matches the "objects" array. We extend the array when: 1. The objects array is extended, in which case we use realloc to extend the tree_depth array. 2. A caller asks to store a tree_depth for object N, and this is the first such request; we create the array from scratch and store the value for N. In the latter case, though, we use regular xmalloc(), and the depth values for any objects besides N is undefined. This happens to not trigger a bug with the current code, but the reasons are quite subtle: - we never ask about the depth for any object with index i < N. This is because we store the depth immediately for all trees and blobs. So any such "i" must be a non-tree, and therefore we will never need to care about its depth (in fact, we really only care about the depth of trees). - there are no objects at this point with index i > N, because we always fill in the depth for a tree immediately after its object entry is created (we may still allocate uninitialized depth entries, but they'll be initialized by packlist_alloc() when it initializes the entry in the "objects" array). So it works, but only by chance. To be defensive, let's zero the array, which matches the "unset" values which would be handed out by oe_tree_depth() already. Signed-off-by: Jeff King Signed-off-by: Junio C Hamano

pack-objects: fix tree_depth and layer invariants

2018-11-21T04:50:16Z

Commit 108f530385 (pack-objects: move tree_depth into 'struct packing_data', 2018-08-16) dynamically manages a tree_depth array in packing_data that maintains one of these invariants: 1. tree_depth is NULL (i.e., the requested options don't require us to track tree depths) 2. tree_depth is non-NULL and has as many entries as the "objects" array We maintain (2) by: a. When the objects array grows, grow tree_depth to the same size (unless it's NULL, in which case we can leave it). b. When a caller asks to set a depth via oe_set_tree_depth(), if tree_depth is NULL we allocate it. But in (b), we use the number of stored objects, _not_ the allocated size of the objects array. So we can run into a situation like this: 1. packlist_alloc() needs to store the Nth object, so it grows the objects array to M, where M > N. 2. oe_set_tree_depth() wants to store a depth, so it allocates an array of length N. Now we've violated our invariant. 3. packlist_alloc() needs to store the N+1th object. But it _doesn't_ grow the objects array, since N <= M still holds. We try to assign to tree_depth[N+1], which is out of bounds. That doesn't happen in our test scripts, because the repositories they use are so small, but it's easy to trigger by running: echo HEAD | git pack-objects --revs --delta-islands --stdout >/dev/null in any reasonably-sized repo (like git.git). We can fix it by always growing the array to match pack->nr_alloc, not pack->nr_objects. Likewise for the "layer" array from fe0ac2fb7f (pack-objects: move 'layer' into 'struct packing_data', 2018-08-16), which has the same bug. Signed-off-by: Jeff King Signed-off-by: Junio C Hamano

Merge branch 'nd/pthreads'

2018-11-18T09:23:52Z

The codebase has been cleaned up to reduce "#ifndef NO_PTHREADS". * nd/pthreads: Clean up pthread_create() error handling read-cache.c: initialize copy_len to shut up gcc 8 read-cache.c: reduce branching based on HAVE_THREADS read-cache.c: remove #ifdef NO_PTHREADS pack-objects: remove #ifdef NO_PTHREADS preload-index.c: remove #ifdef NO_PTHREADS grep: clean up num_threads handling grep: remove #ifdef NO_PTHREADS attr.c: remove #ifdef NO_PTHREADS name-hash.c: remove #ifdef NO_PTHREADS index-pack: remove #ifdef NO_PTHREADS send-pack.c: move async's #ifdef NO_PTHREADS back to run-command.c run-command.h: include thread-utils.h instead of pthread.h thread-utils: macros to unconditionally compile pthreads API