Files
tromcho.net/src/blockstore_impl.cpp
T
Vitaliy Filippov e950c024d3 Do not sync peer OSDs before listing
Sync before listing was added to wait for all PG writes possibly left in queue
from the previous master to finish before listing it

But in fact it may block the cluster when EC is used and some unstable writes
are left in the queue - they block journal flushing, rollback/stabilize is
required to unblock them, but rollback/stabilize may only happen after PG is
peered. But peering needs listings, listings are requested only after sync, and
sync itself waits for currently blocked writes waiting in the queue
2023-01-03 00:05:45 +03:00

688 lines
22 KiB
C++

// Copyright (c) Vitaliy Filippov, 2019+
// License: VNPL-1.1 (see README.md for details)
#include "blockstore_impl.h"
blockstore_impl_t::blockstore_impl_t(blockstore_config_t & config, ring_loop_t *ringloop, timerfd_manager_t *tfd)
{
assert(sizeof(blockstore_op_private_t) <= BS_OP_PRIVATE_DATA_SIZE);
this->tfd = tfd;
this->ringloop = ringloop;
ring_consumer.loop = [this]() { loop(); };
ringloop->register_consumer(&ring_consumer);
initialized = 0;
parse_config(config);
zero_object = (uint8_t*)memalign_or_die(MEM_ALIGNMENT, dsk.data_block_size);
try
{
dsk.open_data();
dsk.open_meta();
dsk.open_journal();
calc_lengths();
data_alloc = new allocator(dsk.block_count);
}
catch (std::exception & e)
{
dsk.close_all();
throw;
}
flusher = new journal_flusher_t(this);
}
blockstore_impl_t::~blockstore_impl_t()
{
delete data_alloc;
delete flusher;
free(zero_object);
ringloop->unregister_consumer(&ring_consumer);
dsk.close_all();
if (metadata_buffer)
free(metadata_buffer);
if (clean_bitmap)
free(clean_bitmap);
}
bool blockstore_impl_t::is_started()
{
return initialized == 10;
}
bool blockstore_impl_t::is_stalled()
{
return queue_stall;
}
// main event loop - produce requests
void blockstore_impl_t::loop()
{
// FIXME: initialized == 10 is ugly
if (initialized != 10)
{
// read metadata, then journal
if (initialized == 0)
{
metadata_init_reader = new blockstore_init_meta(this);
initialized = 1;
}
if (initialized == 1)
{
int res = metadata_init_reader->loop();
if (!res)
{
delete metadata_init_reader;
metadata_init_reader = NULL;
journal_init_reader = new blockstore_init_journal(this);
initialized = 2;
}
}
if (initialized == 2)
{
int res = journal_init_reader->loop();
if (!res)
{
delete journal_init_reader;
journal_init_reader = NULL;
if (journal.flush_journal)
initialized = 3;
else
initialized = 10;
ringloop->wakeup();
}
}
if (initialized == 3)
{
if (readonly)
{
printf("Can't flush the journal in readonly mode\n");
exit(1);
}
flusher->loop();
ringloop->submit();
}
}
else
{
// try to submit ops
unsigned initial_ring_space = ringloop->space_left();
// has_writes == 0 - no writes before the current queue item
// has_writes == 1 - some writes in progress
// has_writes == 2 - tried to submit some writes, but failed
int has_writes = 0, op_idx = 0, new_idx = 0;
for (; op_idx < submit_queue.size(); op_idx++, new_idx++)
{
auto op = submit_queue[op_idx];
submit_queue[new_idx] = op;
// FIXME: This needs some simplification
// Writes should not block reads if the ring is not full and reads don't depend on them
// In all other cases we should stop submission
if (PRIV(op)->wait_for)
{
check_wait(op);
if (PRIV(op)->wait_for == WAIT_SQE)
{
break;
}
else if (PRIV(op)->wait_for)
{
if (op->opcode == BS_OP_WRITE || op->opcode == BS_OP_WRITE_STABLE || op->opcode == BS_OP_DELETE)
{
has_writes = 2;
}
continue;
}
}
unsigned prev_sqe_pos = ringloop->save();
// 0 = can't submit
// 1 = in progress
// 2 = can be removed from queue
int wr_st = 0;
if (op->opcode == BS_OP_READ)
{
wr_st = dequeue_read(op);
}
else if (op->opcode == BS_OP_WRITE || op->opcode == BS_OP_WRITE_STABLE)
{
if (has_writes == 2)
{
// Some writes already could not be submitted
continue;
}
wr_st = dequeue_write(op);
has_writes = wr_st > 0 ? 1 : 2;
}
else if (op->opcode == BS_OP_DELETE)
{
if (has_writes == 2)
{
// Some writes already could not be submitted
continue;
}
wr_st = dequeue_del(op);
has_writes = wr_st > 0 ? 1 : 2;
}
else if (op->opcode == BS_OP_SYNC)
{
// wait for all small writes to be submitted
// wait for all big writes to complete, submit data device fsync
// wait for the data device fsync to complete, then submit journal writes for big writes
// then submit an fsync operation
if (has_writes)
{
// Can't submit SYNC before previous writes
continue;
}
wr_st = continue_sync(op, false);
if (wr_st != 2)
{
has_writes = wr_st > 0 ? 1 : 2;
}
}
else if (op->opcode == BS_OP_STABLE)
{
wr_st = dequeue_stable(op);
}
else if (op->opcode == BS_OP_ROLLBACK)
{
wr_st = dequeue_rollback(op);
}
else if (op->opcode == BS_OP_LIST)
{
// LIST doesn't have to be blocked by previous modifications
process_list(op);
wr_st = 2;
}
if (wr_st == 2)
{
submit_queue[op_idx] = NULL;
new_idx--;
}
if (wr_st == 0)
{
ringloop->restore(prev_sqe_pos);
if (PRIV(op)->wait_for == WAIT_SQE)
{
// ring is full, stop submission
break;
}
}
}
if (op_idx != new_idx)
{
while (op_idx < submit_queue.size())
{
submit_queue[new_idx++] = submit_queue[op_idx++];
}
submit_queue.resize(new_idx);
}
if (!readonly)
{
flusher->loop();
}
int ret = ringloop->submit();
if (ret < 0)
{
throw std::runtime_error(std::string("io_uring_submit: ") + strerror(-ret));
}
for (auto s: journal.submitting_sectors)
{
// Mark journal sector writes as submitted
journal.sector_info[s].submit_id = 0;
}
journal.submitting_sectors.clear();
if ((initial_ring_space - ringloop->space_left()) > 0)
{
live = true;
}
queue_stall = !live && !ringloop->has_work();
live = false;
}
}
bool blockstore_impl_t::is_safe_to_stop()
{
// It's safe to stop blockstore when there are no in-flight operations,
// no in-progress syncs and flusher isn't doing anything
if (submit_queue.size() > 0 || !readonly && flusher->is_active())
{
return false;
}
if (unsynced_big_writes.size() > 0 || unsynced_small_writes.size() > 0)
{
if (!readonly && !stop_sync_submitted)
{
// We should sync the blockstore before unmounting
blockstore_op_t *op = new blockstore_op_t;
op->opcode = BS_OP_SYNC;
op->buf = NULL;
op->callback = [](blockstore_op_t *op)
{
delete op;
};
enqueue_op(op);
stop_sync_submitted = true;
}
return false;
}
return true;
}
void blockstore_impl_t::check_wait(blockstore_op_t *op)
{
if (PRIV(op)->wait_for == WAIT_SQE)
{
if (ringloop->sqes_left() < PRIV(op)->wait_detail)
{
// stop submission if there's still no free space
#ifdef BLOCKSTORE_DEBUG
printf("Still waiting for %lu SQE(s)\n", PRIV(op)->wait_detail);
#endif
return;
}
PRIV(op)->wait_for = 0;
}
else if (PRIV(op)->wait_for == WAIT_JOURNAL)
{
if (journal.used_start == PRIV(op)->wait_detail)
{
// do not submit
#ifdef BLOCKSTORE_DEBUG
printf("Still waiting to flush journal offset %08lx\n", PRIV(op)->wait_detail);
#endif
return;
}
flusher->release_trim();
PRIV(op)->wait_for = 0;
}
else if (PRIV(op)->wait_for == WAIT_JOURNAL_BUFFER)
{
int next = ((journal.cur_sector + 1) % journal.sector_count);
if (journal.sector_info[next].flush_count > 0 ||
journal.sector_info[next].dirty)
{
// do not submit
#ifdef BLOCKSTORE_DEBUG
printf("Still waiting for a journal buffer\n");
#endif
return;
}
PRIV(op)->wait_for = 0;
}
else
{
throw std::runtime_error("BUG: op->wait_for value is unexpected");
}
}
void blockstore_impl_t::enqueue_op(blockstore_op_t *op)
{
if (op->opcode < BS_OP_MIN || op->opcode > BS_OP_MAX ||
((op->opcode == BS_OP_READ || op->opcode == BS_OP_WRITE || op->opcode == BS_OP_WRITE_STABLE) && (
op->offset >= dsk.data_block_size ||
op->len > dsk.data_block_size-op->offset ||
(op->len % dsk.disk_alignment)
)) ||
readonly && op->opcode != BS_OP_READ && op->opcode != BS_OP_LIST)
{
// Basic verification not passed
op->retval = -EINVAL;
std::function<void (blockstore_op_t*)>(op->callback)(op);
return;
}
if (op->opcode == BS_OP_SYNC_STAB_ALL)
{
std::function<void(blockstore_op_t*)> *old_callback = new std::function<void(blockstore_op_t*)>(op->callback);
op->opcode = BS_OP_SYNC;
op->callback = [this, old_callback](blockstore_op_t *op)
{
if (op->retval >= 0 && unstable_writes.size() > 0)
{
op->opcode = BS_OP_STABLE;
op->len = unstable_writes.size();
obj_ver_id *vers = new obj_ver_id[op->len];
op->buf = vers;
int i = 0;
for (auto it = unstable_writes.begin(); it != unstable_writes.end(); it++, i++)
{
vers[i] = {
.oid = it->first,
.version = it->second,
};
}
unstable_writes.clear();
op->callback = [old_callback](blockstore_op_t *op)
{
obj_ver_id *vers = (obj_ver_id*)op->buf;
delete[] vers;
op->buf = NULL;
(*old_callback)(op);
delete old_callback;
};
this->enqueue_op(op);
}
else
{
(*old_callback)(op);
delete old_callback;
}
};
}
if ((op->opcode == BS_OP_WRITE || op->opcode == BS_OP_WRITE_STABLE || op->opcode == BS_OP_DELETE) && !enqueue_write(op))
{
std::function<void (blockstore_op_t*)>(op->callback)(op);
return;
}
// Call constructor without allocating memory. We'll call destructor before returning op back
new ((void*)op->private_data) blockstore_op_private_t;
PRIV(op)->wait_for = 0;
PRIV(op)->op_state = 0;
PRIV(op)->pending_ops = 0;
submit_queue.push_back(op);
ringloop->wakeup();
}
static bool replace_stable(object_id oid, uint64_t version, int search_start, int search_end, obj_ver_id* list)
{
while (search_start < search_end)
{
int pos = search_start+(search_end-search_start)/2;
if (oid < list[pos].oid)
{
search_end = pos;
}
else if (list[pos].oid < oid)
{
search_start = pos+1;
}
else
{
list[pos].version = version;
return true;
}
}
return false;
}
blockstore_clean_db_t& blockstore_impl_t::clean_db_shard(object_id oid)
{
uint64_t pg_num = 0;
uint64_t pool_id = (oid.inode >> (64-POOL_ID_BITS));
auto sh_it = clean_db_settings.find(pool_id);
if (sh_it != clean_db_settings.end())
{
// like map_to_pg()
pg_num = (oid.stripe / sh_it->second.pg_stripe_size) % sh_it->second.pg_count + 1;
}
return clean_db_shards[(pool_id << (64-POOL_ID_BITS)) | pg_num];
}
void blockstore_impl_t::reshard_clean_db(pool_id_t pool, uint32_t pg_count, uint32_t pg_stripe_size)
{
uint64_t pool_id = (uint64_t)pool;
std::map<pool_pg_id_t, blockstore_clean_db_t> new_shards;
auto sh_it = clean_db_shards.lower_bound((pool_id << (64-POOL_ID_BITS)));
while (sh_it != clean_db_shards.end() &&
(sh_it->first >> (64-POOL_ID_BITS)) == pool_id)
{
for (auto & pair: sh_it->second)
{
// like map_to_pg()
uint64_t pg_num = (pair.first.stripe / pg_stripe_size) % pg_count + 1;
uint64_t shard_id = (pool_id << (64-POOL_ID_BITS)) | pg_num;
new_shards[shard_id][pair.first] = pair.second;
}
clean_db_shards.erase(sh_it++);
}
for (sh_it = new_shards.begin(); sh_it != new_shards.end(); sh_it++)
{
auto & to = clean_db_shards[sh_it->first];
to.swap(sh_it->second);
}
clean_db_settings[pool_id] = (pool_shard_settings_t){
.pg_count = pg_count,
.pg_stripe_size = pg_stripe_size,
};
}
void blockstore_impl_t::process_list(blockstore_op_t *op)
{
uint32_t list_pg = op->offset+1;
uint32_t pg_count = op->len;
uint64_t pg_stripe_size = op->oid.stripe;
uint64_t min_inode = op->oid.inode;
uint64_t max_inode = op->version;
// Check PG
if (pg_count != 0 && (pg_stripe_size < MIN_DATA_BLOCK_SIZE || list_pg > pg_count))
{
op->retval = -EINVAL;
FINISH_OP(op);
return;
}
// Check if the DB needs resharding
// (we don't know about PGs from the beginning, we only create "shards" here)
uint64_t first_shard = 0, last_shard = UINT64_MAX;
if (min_inode != 0 &&
// Check if min_inode == max_inode == pool_id<<N, i.e. this is a pool listing
(min_inode >> (64-POOL_ID_BITS)) == (max_inode >> (64-POOL_ID_BITS)))
{
pool_id_t pool_id = (min_inode >> (64-POOL_ID_BITS));
if (pg_count > 1)
{
// Per-pg listing
auto sh_it = clean_db_settings.find(pool_id);
if (sh_it == clean_db_settings.end() ||
sh_it->second.pg_count != pg_count ||
sh_it->second.pg_stripe_size != pg_stripe_size)
{
reshard_clean_db(pool_id, pg_count, pg_stripe_size);
}
first_shard = last_shard = ((uint64_t)pool_id << (64-POOL_ID_BITS)) | list_pg;
}
else
{
// Per-pool listing
first_shard = ((uint64_t)pool_id << (64-POOL_ID_BITS));
last_shard = ((uint64_t)(pool_id+1) << (64-POOL_ID_BITS)) - 1;
}
}
// Copy clean_db entries
int stable_count = 0, stable_alloc = 0;
if (min_inode != max_inode)
{
for (auto shard_it = clean_db_shards.lower_bound(first_shard);
shard_it != clean_db_shards.end() && shard_it->first <= last_shard;
shard_it++)
{
auto & clean_db = shard_it->second;
stable_alloc += clean_db.size();
}
}
else
{
stable_alloc = 32768;
}
obj_ver_id *stable = (obj_ver_id*)malloc(sizeof(obj_ver_id) * stable_alloc);
if (!stable)
{
op->retval = -ENOMEM;
FINISH_OP(op);
return;
}
for (auto shard_it = clean_db_shards.lower_bound(first_shard);
shard_it != clean_db_shards.end() && shard_it->first <= last_shard;
shard_it++)
{
auto & clean_db = shard_it->second;
auto clean_it = clean_db.begin(), clean_end = clean_db.end();
if ((min_inode != 0 || max_inode != 0) && min_inode <= max_inode)
{
clean_it = clean_db.lower_bound({
.inode = min_inode,
.stripe = 0,
});
clean_end = clean_db.upper_bound({
.inode = max_inode,
.stripe = UINT64_MAX,
});
}
for (; clean_it != clean_end; clean_it++)
{
if (stable_count >= stable_alloc)
{
stable_alloc *= 2;
stable = (obj_ver_id*)realloc(stable, sizeof(obj_ver_id) * stable_alloc);
if (!stable)
{
op->retval = -ENOMEM;
FINISH_OP(op);
return;
}
}
stable[stable_count++] = {
.oid = clean_it->first,
.version = clean_it->second.version,
};
}
}
if (first_shard != last_shard)
{
// If that's not a per-PG listing, sort clean entries
std::sort(stable, stable+stable_count);
}
int clean_stable_count = stable_count;
// Copy dirty_db entries (sorted, too)
int unstable_count = 0, unstable_alloc = 0;
obj_ver_id *unstable = NULL;
{
auto dirty_it = dirty_db.begin(), dirty_end = dirty_db.end();
if ((min_inode != 0 || max_inode != 0) && min_inode <= max_inode)
{
dirty_it = dirty_db.lower_bound({
.oid = {
.inode = min_inode,
.stripe = 0,
},
.version = 0,
});
dirty_end = dirty_db.upper_bound({
.oid = {
.inode = max_inode,
.stripe = UINT64_MAX,
},
.version = UINT64_MAX,
});
}
for (; dirty_it != dirty_end; dirty_it++)
{
if (!pg_count || ((dirty_it->first.oid.stripe / pg_stripe_size) % pg_count + 1) == list_pg) // like map_to_pg()
{
if (IS_DELETE(dirty_it->second.state))
{
// Deletions are always stable, so try to zero out two possible entries
if (!replace_stable(dirty_it->first.oid, 0, 0, clean_stable_count, stable))
{
replace_stable(dirty_it->first.oid, 0, clean_stable_count, stable_count, stable);
}
}
else if (IS_STABLE(dirty_it->second.state) || (dirty_it->second.state & BS_ST_INSTANT))
{
// First try to replace a clean stable version in the first part of the list
if (!replace_stable(dirty_it->first.oid, dirty_it->first.version, 0, clean_stable_count, stable))
{
// Then try to replace the last dirty stable version in the second part of the list
if (stable_count > 0 && stable[stable_count-1].oid == dirty_it->first.oid)
{
stable[stable_count-1].version = dirty_it->first.version;
}
else
{
if (stable_count >= stable_alloc)
{
stable_alloc += 32768;
stable = (obj_ver_id*)realloc(stable, sizeof(obj_ver_id) * stable_alloc);
if (!stable)
{
if (unstable)
free(unstable);
op->retval = -ENOMEM;
FINISH_OP(op);
return;
}
}
stable[stable_count++] = dirty_it->first;
}
}
}
else
{
if (unstable_count >= unstable_alloc)
{
unstable_alloc += 32768;
unstable = (obj_ver_id*)realloc(unstable, sizeof(obj_ver_id) * unstable_alloc);
if (!unstable)
{
if (stable)
free(stable);
op->retval = -ENOMEM;
FINISH_OP(op);
return;
}
}
unstable[unstable_count++] = dirty_it->first;
}
}
}
}
// Remove zeroed out stable entries
int j = 0;
for (int i = 0; i < stable_count; i++)
{
if (stable[i].version != 0)
{
stable[j++] = stable[i];
}
}
stable_count = j;
if (stable_count+unstable_count > stable_alloc)
{
stable_alloc = stable_count+unstable_count;
stable = (obj_ver_id*)realloc(stable, sizeof(obj_ver_id) * stable_alloc);
if (!stable)
{
if (unstable)
free(unstable);
op->retval = -ENOMEM;
FINISH_OP(op);
return;
}
}
// Copy unstable entries
for (int i = 0; i < unstable_count; i++)
{
stable[j++] = unstable[i];
}
free(unstable);
op->version = stable_count;
op->retval = stable_count+unstable_count;
op->buf = stable;
FINISH_OP(op);
}
void blockstore_impl_t::dump_diagnostics()
{
journal.dump_diagnostics();
flusher->dump_diagnostics();
}
void blockstore_impl_t::disk_error_abort(const char *op, int retval, int expected)
{
if (retval == -EAGAIN)
{
fprintf(stderr, "EAGAIN error received from a disk %s during flush."
" It must never happen with io_uring and indicates a kernel bug."
" Please upgrade your kernel. Aborting.\n", op);
exit(1);
}
fprintf(stderr, "Disk %s failed: result is %d, expected %d. Can't continue, sorry :-(\n", op, retval, expected);
exit(1);
}