Implement blockstore rollback operation

Rollback operation is required for the primary OSD to kill unstable
object versions in OSD peers so they don't occupy journal space
This commit is contained in:
Vitaliy Filippov
2020-01-24 20:18:14 +03:00
parent 98efdb78bd
commit 2b09710d6f
13 changed files with 291 additions and 55 deletions
+187
View File
@@ -0,0 +1,187 @@
#include "blockstore_impl.h"
int blockstore_impl_t::dequeue_rollback(blockstore_op_t *op)
{
obj_ver_id* v;
int i, todo = op->len;
for (i = 0, v = (obj_ver_id*)op->buf; i < op->len; i++, v++)
{
// Check that there are some versions greater than v->version (which may be zero),
// check that they're unstable, synced, and not currently written to
auto dirty_it = dirty_db.lower_bound((obj_ver_id){
.oid = v->oid,
.version = UINT64_MAX,
});
if (dirty_it == dirty_db.begin())
{
bad_op:
op->retval = -EINVAL;
FINISH_OP(op);
return 1;
}
else
{
dirty_it--;
if (dirty_it->first.oid != v->oid || dirty_it->first.version < v->version)
{
goto bad_op;
}
while (dirty_it->first.oid == v->oid && dirty_it->first.version > v->version)
{
if (!IS_SYNCED(dirty_it->second.state) ||
IS_STABLE(dirty_it->second.state))
{
goto bad_op;
}
if (dirty_it == dirty_db.begin())
{
break;
}
dirty_it--;
}
}
}
// Check journal space
blockstore_journal_check_t space_check(this);
if (!space_check.check_available(op, todo, sizeof(journal_entry_rollback), 0))
{
return 0;
}
// There is sufficient space. Get SQEs
struct io_uring_sqe *sqe[space_check.sectors_required];
for (i = 0; i < space_check.sectors_required; i++)
{
BS_SUBMIT_GET_SQE_DECL(sqe[i]);
}
// Prepare and submit journal entries
auto cb = [this, op](ring_data_t *data) { handle_rollback_event(data, op); };
int s = 0, cur_sector = -1;
if ((journal_block_size - journal.in_sector_pos) < sizeof(journal_entry_rollback) &&
journal.sector_info[journal.cur_sector].dirty)
{
if (cur_sector == -1)
PRIV(op)->min_used_journal_sector = 1 + journal.cur_sector;
cur_sector = journal.cur_sector;
prepare_journal_sector_write(journal, cur_sector, sqe[s++], cb);
}
for (i = 0, v = (obj_ver_id*)op->buf; i < op->len; i++, v++)
{
// FIXME This is here only for the purpose of tracking unstable_writes. Remove if not required
// FIXME ...aaaand this is similar to blockstore_init.cpp - maybe dedup it?
auto dirty_it = dirty_db.lower_bound((obj_ver_id){
.oid = v->oid,
.version = UINT64_MAX,
});
uint64_t max_unstable = 0;
while (dirty_it != dirty_db.begin())
{
dirty_it--;
if (dirty_it->first.oid != v->oid)
break;
else if (dirty_it->first.version <= v->version)
{
if (!IS_STABLE(dirty_it->second.state))
max_unstable = dirty_it->first.version;
break;
}
}
auto unstab_it = unstable_writes.find(v->oid);
if (unstab_it != unstable_writes.end())
{
if (max_unstable == 0)
unstable_writes.erase(unstab_it);
else
unstab_it->second = max_unstable;
}
journal_entry_rollback *je = (journal_entry_rollback*)
prefill_single_journal_entry(journal, JE_ROLLBACK, sizeof(journal_entry_rollback));
journal.sector_info[journal.cur_sector].dirty = false;
je->oid = v->oid;
je->version = v->version;
je->crc32 = je_crc32((journal_entry*)je);
journal.crc32_last = je->crc32;
if (cur_sector != journal.cur_sector)
{
if (cur_sector == -1)
PRIV(op)->min_used_journal_sector = 1 + journal.cur_sector;
cur_sector = journal.cur_sector;
prepare_journal_sector_write(journal, cur_sector, sqe[s++], cb);
}
}
PRIV(op)->max_used_journal_sector = 1 + journal.cur_sector;
PRIV(op)->pending_ops = s;
return 1;
}
void blockstore_impl_t::handle_rollback_event(ring_data_t *data, blockstore_op_t *op)
{
live = true;
if (data->res != data->iov.iov_len)
{
throw std::runtime_error(
"write operation failed ("+std::to_string(data->res)+" != "+std::to_string(data->iov.iov_len)+
"). in-memory state is corrupted. AAAAAAAaaaaaaaaa!!!111"
);
}
PRIV(op)->pending_ops--;
if (PRIV(op)->pending_ops == 0)
{
// Release used journal sectors
release_journal_sectors(op);
obj_ver_id* v;
int i;
for (i = 0, v = (obj_ver_id*)op->buf; i < op->len; i++, v++)
{
// Erase dirty_db entries
auto rm_end = dirty_db.lower_bound((obj_ver_id){
.oid = v->oid,
.version = UINT64_MAX,
});
rm_end--;
auto rm_start = rm_end;
while (1)
{
if (rm_end->first.oid != v->oid)
break;
else if (rm_end->first.version <= v->version)
break;
rm_start = rm_end;
if (rm_end == dirty_db.begin())
break;
rm_end--;
}
if (rm_end != rm_start)
erase_dirty(rm_start, rm_end, UINT64_MAX);
}
journal.trim();
// Acknowledge op
op->retval = 0;
FINISH_OP(op);
}
}
void blockstore_impl_t::erase_dirty(blockstore_dirty_db_t::iterator dirty_start, blockstore_dirty_db_t::iterator dirty_end, uint64_t clean_loc)
{
auto dirty_it = dirty_end;
while (dirty_it != dirty_start)
{
dirty_it--;
if (IS_BIG_WRITE(dirty_it->second.state) && dirty_it->second.location != clean_loc)
{
#ifdef BLOCKSTORE_DEBUG
printf("Free block %lu\n", dirty_it->second.location >> block_order);
#endif
data_alloc->set(dirty_it->second.location >> block_order, false);
}
#ifdef BLOCKSTORE_DEBUG
printf("remove usage of journal offset %lu by %lu:%lu v%lu\n", dirty_it->second.journal_sector,
dirty_it->first.oid.inode, dirty_it->first.oid.stripe, dirty_it->first.version);
#endif
int used = --journal.used_sectors[dirty_it->second.journal_sector];
if (used == 0)
{
journal.used_sectors.erase(dirty_it->second.journal_sector);
}
}
dirty_db.erase(dirty_start, dirty_end);
}