From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Vladimir Davydov Subject: [PATCH 17/25] vinyl: pin last statement returned by write iterator explicitly Date: Fri, 27 Jul 2018 14:29:57 +0300 Message-Id: <7269545e5e9bafdd6ef00274296e214d68950599.1532689066.git.vdavydov.dev@gmail.com> In-Reply-To: References: In-Reply-To: References: To: kostja@tarantool.org Cc: tarantool-patches@freelists.org List-ID: Currently, the last statement returned by the write iterator is pinned indirectly, via a read view. This works, because the write iterator can only return a statement if it corresponds to a certain read view. However, in the scope of #2129, the write iterator will also have to keep statements for which a deferred DELETE hasn't been generated yet, even if no read view needs it. So let's make the write iterator pin the last returned statement explicitly, i.e. via a dedicated member of the write_iterator struct. Needed for #2129 --- src/box/vy_write_iterator.c | 20 +++++++++++++------- 1 file changed, 13 insertions(+), 7 deletions(-) diff --git a/src/box/vy_write_iterator.c b/src/box/vy_write_iterator.c index 4e758be8..06ae342b 100644 --- a/src/box/vy_write_iterator.c +++ b/src/box/vy_write_iterator.c @@ -192,6 +192,10 @@ struct vy_write_iterator { */ int stmt_i; /** + * Last statement returned to the caller, pinned in memory. + */ + struct tuple *last_stmt; + /** * Read views of the same key sorted by LSN in descending * order, starting from INT64_MAX. * @@ -398,6 +402,10 @@ vy_write_iterator_stop(struct vy_stmt_stream *vstream) struct vy_write_src *src, *tmp; rlist_foreach_entry_safe(src, &stream->src_list, in_src_list, tmp) vy_write_iterator_delete_src(stream, src); + if (stream->last_stmt != NULL) { + vy_stmt_unref_if_possible(stream->last_stmt); + stream->last_stmt = NULL; + } } /** @@ -527,12 +535,6 @@ static inline struct tuple * vy_write_iterator_pop_read_view_stmt(struct vy_write_iterator *stream) { struct vy_read_view_stmt *rv; - if (stream->stmt_i >= 0) { - /* Destroy the current before getting to the next. */ - rv = &stream->read_views[stream->stmt_i]; - assert(rv->history == NULL); - vy_read_view_stmt_destroy(rv); - } if (stream->rv_used_count == 0) return NULL; /* Find a next non-empty history element. */ @@ -544,7 +546,11 @@ vy_write_iterator_pop_read_view_stmt(struct vy_write_iterator *stream) } while (rv->tuple == NULL); assert(stream->rv_used_count > 0); stream->rv_used_count--; - return rv->tuple; + if (stream->last_stmt != NULL) + vy_stmt_unref_if_possible(stream->last_stmt); + stream->last_stmt = rv->tuple; + rv->tuple = NULL; + return stream->last_stmt; } /** -- 2.11.0