[PATCH 1/3] line-log: free diff queue when processing non-merge commits
- From
SZEDER Gábor <szeder.dev@gmail.com>
- Date
- Nov 2, 2022, 22:01 UTC
- Message-ID
- <20221102220142.574890-2-szeder.dev@gmail.com>
- In-Reply-To
- <20221102220142.574890-1-szeder.dev@gmail.com>
When processing a non-merge commit, the line-level log first asks the tree-diff machinery whether any of the files in the given line ranges were modified between the current commit and its parent, and if some of them were, then it loads the contents of those files from both commits to see whether their line ranges were modified and/or need to be adjusted. Alas, it doesn't free() the diff queue holding the results of that query and the contents of those files once its done. This can add up to a substantial amount of leaked memory, especially when the file in question is big and is frequently modified: a user reported "Out of memory, malloc failed" errors with a 2MB text file that was modified ~2800 times [1] (I estimate the leak would use up almost 11GB memory in that case).
Free that diff queue to plug this memory leak. However, instead of simply open-coding the necessary three lines, add them as a helper function to the diff API, because it will be useful elsewhere as well.
[1] https://public-inbox.org/git/CAFOPqVXz2XwzX8vGU7wLuqb2ZuwTuOFAzBLRM_QPk+NJa=eC-g@mail.gmail.com/
Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com> --- diff.c | 7 +++++++ diffcore.h | 1 + line-log.c | 1 + 3 files changed, 9 insertions(+)
diff --git a/diff.c b/diff.c index 35e46dd968..ef94175163 100644 --- a/diff.c +++ b/diff.c @@ -5773,6 +5773,13 @@ void diff_free_filepair(struct diff_filepair *p) free(p); } +void diff_free_queue(struct diff_queue_struct *q) +{ + for (int i = 0; i < q->nr; i++) + diff_free_filepair(q->queue[i]); + free(q->queue); +} + const char *diff_aligned_abbrev(const struct object_id *oid, int len) { int abblen; diff --git a/diffcore.h b/diffcore.h index badc2261c2..9b588a1ee1 100644 --- a/diffcore.h +++ b/diffcore.h @@ -162,6 +162,7 @@ struct diff_filepair *diff_queue(struct diff_queue_struct *, struct diff_filespec *, struct diff_filespec *); void diff_q(struct diff_queue_struct *, struct diff_filepair *); +void diff_free_queue(struct diff_queue_struct *q); /* dir_rename_relevance: the reason we want rename information for a dir */ enum dir_rename_relevance { diff --git a/line-log.c b/line-log.c index 51d93310a4..7a74daf2e8 100644 --- a/line-log.c +++ b/line-log.c @@ -1195,6 +1195,7 @@ static int process_ranges_ordinary_commit(struct rev_info *rev, struct commit *c if (parent) add_line_range(rev, parent, parent_range); free_line_log_data(parent_range); + diff_free_queue(&queue); return changed; }
-- 2.38.1.564.g99c012faba