Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Jump to bottom

rbd-mirror: fix potential infinite loop when formatting status message #20349

Merged
merged 1 commit into from Feb 9, 2018
Merged

rbd-mirror: fix potential infinite loop when formatting status message #20349

Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Jump to
Jump to file
Failed to load files.
Diff view
Diff view
28 changes: 13 additions & 15 deletions src/tools/rbd_mirror/image_replayer/ReplayStatusFormatter.cc
View file
Open in desktop
Expand Up @@ -112,18 +112,20 @@ bool ReplayStatusFormatter<I>::calculate_behind_master_or_send_update() {
cls::journal::ObjectPosition master = m_master_position;
uint64_t mirror_tag_tid = m_mirror_position.tag_tid;

while (master.tag_tid != mirror_tag_tid) {
while (master.tag_tid > mirror_tag_tid) {
auto tag_it = m_tag_cache.find(master.tag_tid);
if (tag_it == m_tag_cache.end()) {
send_update_tag_cache(master.tag_tid, mirror_tag_tid);
return false;
}
librbd::journal::TagData &tag_data = tag_it->second;
m_entries_behind_master += master.entry_tid;
master = cls::journal::ObjectPosition(0, tag_data.predecessor.tag_tid,
tag_data.predecessor.entry_tid);
master = {0, tag_data.predecessor.tag_tid, tag_data.predecessor.entry_tid};
}
if (master.tag_tid == mirror_tag_tid &&
master.entry_tid > m_mirror_position.entry_tid) {
m_entries_behind_master += master.entry_tid - m_mirror_position.entry_tid;
}
m_entries_behind_master += master.entry_tid - m_mirror_position.entry_tid;

dout(20) << "clearing tags not needed any more (below mirror position)"
<< dendl;
Expand Down Expand Up @@ -152,11 +154,8 @@ bool ReplayStatusFormatter<I>::calculate_behind_master_or_send_update() {
template <typename I>
void ReplayStatusFormatter<I>::send_update_tag_cache(uint64_t master_tag_tid,
uint64_t mirror_tag_tid) {

dout(20) << "master_tag_tid=" << master_tag_tid << ", mirror_tag_tid="
<< mirror_tag_tid << dendl;

if (master_tag_tid == mirror_tag_tid) {
if (master_tag_tid <= mirror_tag_tid ||
m_tag_cache.find(master_tag_tid) != m_tag_cache.end()) {
Context *on_finish = nullptr;
{
Mutex::Locker locker(m_lock);
Expand All @@ -168,6 +167,9 @@ void ReplayStatusFormatter<I>::send_update_tag_cache(uint64_t master_tag_tid,
return;
}

dout(20) << "master_tag_tid=" << master_tag_tid << ", mirror_tag_tid="
<< mirror_tag_tid << dendl;

FunctionContext *ctx = new FunctionContext(
[this, master_tag_tid, mirror_tag_tid](int r) {
handle_update_tag_cache(master_tag_tid, mirror_tag_tid, r);
Expand Down Expand Up @@ -201,16 +203,12 @@ void ReplayStatusFormatter<I>::handle_update_tag_cache(uint64_t master_tag_tid,
tag_data.predecessor.mirror_uuid !=
librbd::Journal<>::ORPHAN_MIRROR_UUID) {
dout(20) << "hit remote image non-primary epoch" << dendl;
tag_data.predecessor.tag_tid = mirror_tag_tid;
} else if (tag_data.predecessor.tag_tid == 0) {
// We failed. Don't consider this fatal, just terminate retrieving.
dout(20) << "making fake tag" << dendl;
tag_data.predecessor.tag_tid = mirror_tag_tid;
tag_data.predecessor = {};
}

dout(20) << "decoded tag " << master_tag_tid << ": " << tag_data << dendl;

m_tag_cache.insert(std::make_pair(master_tag_tid, tag_data));
m_tag_cache[master_tag_tid] = tag_data;
send_update_tag_cache(tag_data.predecessor.tag_tid, mirror_tag_tid);
}

Expand Down