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-rw-r--r--src/os/bluestore/AvlAllocator.cc474
1 files changed, 474 insertions, 0 deletions
diff --git a/src/os/bluestore/AvlAllocator.cc b/src/os/bluestore/AvlAllocator.cc
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index 000000000..5f17a3689
--- /dev/null
+++ b/src/os/bluestore/AvlAllocator.cc
@@ -0,0 +1,474 @@
+// -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
+// vim: ts=8 sw=2 smarttab
+
+#include "AvlAllocator.h"
+
+#include <limits>
+
+#include "common/config_proxy.h"
+#include "common/debug.h"
+
+#define dout_context cct
+#define dout_subsys ceph_subsys_bluestore
+#undef dout_prefix
+#define dout_prefix *_dout << "AvlAllocator "
+
+MEMPOOL_DEFINE_OBJECT_FACTORY(range_seg_t, range_seg_t, bluestore_alloc);
+
+namespace {
+ // a light-weight "range_seg_t", which only used as the key when searching in
+ // range_tree and range_size_tree
+ struct range_t {
+ uint64_t start;
+ uint64_t end;
+ };
+}
+
+/*
+ * This is a helper function that can be used by the allocator to find
+ * a suitable block to allocate. This will search the specified AVL
+ * tree looking for a block that matches the specified criteria.
+ */
+uint64_t AvlAllocator::_pick_block_after(uint64_t *cursor,
+ uint64_t size,
+ uint64_t align)
+{
+ const auto compare = range_tree.key_comp();
+ uint32_t search_count = 0;
+ uint64_t search_bytes = 0;
+ auto rs_start = range_tree.lower_bound(range_t{*cursor, size}, compare);
+ for (auto rs = rs_start; rs != range_tree.end(); ++rs) {
+ uint64_t offset = p2roundup(rs->start, align);
+ *cursor = offset + size;
+ if (offset + size <= rs->end) {
+ return offset;
+ }
+ if (max_search_count > 0 && ++search_count > max_search_count) {
+ return -1ULL;
+ }
+ if (search_bytes = rs->start - rs_start->start;
+ max_search_bytes > 0 && search_bytes > max_search_bytes) {
+ return -1ULL;
+ }
+ }
+
+ if (*cursor == 0) {
+ // If we already started from beginning, don't bother with searching from beginning
+ return -1ULL;
+ }
+ // If we reached end, start from beginning till cursor.
+ for (auto rs = range_tree.begin(); rs != rs_start; ++rs) {
+ uint64_t offset = p2roundup(rs->start, align);
+ *cursor = offset + size;
+ if (offset + size <= rs->end) {
+ return offset;
+ }
+ if (max_search_count > 0 && ++search_count > max_search_count) {
+ return -1ULL;
+ }
+ if (max_search_bytes > 0 && search_bytes + rs->start > max_search_bytes) {
+ return -1ULL;
+ }
+ }
+ return -1ULL;
+}
+
+uint64_t AvlAllocator::_pick_block_fits(uint64_t size,
+ uint64_t align)
+{
+ // instead of searching from cursor, just pick the smallest range which fits
+ // the needs
+ const auto compare = range_size_tree.key_comp();
+ auto rs_start = range_size_tree.lower_bound(range_t{0, size}, compare);
+ for (auto rs = rs_start; rs != range_size_tree.end(); ++rs) {
+ uint64_t offset = p2roundup(rs->start, align);
+ if (offset + size <= rs->end) {
+ return offset;
+ }
+ }
+ return -1ULL;
+}
+
+void AvlAllocator::_add_to_tree(uint64_t start, uint64_t size)
+{
+ ceph_assert(size != 0);
+
+ uint64_t end = start + size;
+
+ auto rs_after = range_tree.upper_bound(range_t{start, end},
+ range_tree.key_comp());
+
+ /* Make sure we don't overlap with either of our neighbors */
+ auto rs_before = range_tree.end();
+ if (rs_after != range_tree.begin()) {
+ rs_before = std::prev(rs_after);
+ }
+
+ bool merge_before = (rs_before != range_tree.end() && rs_before->end == start);
+ bool merge_after = (rs_after != range_tree.end() && rs_after->start == end);
+
+ if (merge_before && merge_after) {
+ _range_size_tree_rm(*rs_before);
+ _range_size_tree_rm(*rs_after);
+ rs_after->start = rs_before->start;
+ range_tree.erase_and_dispose(rs_before, dispose_rs{});
+ _range_size_tree_try_insert(*rs_after);
+ } else if (merge_before) {
+ _range_size_tree_rm(*rs_before);
+ rs_before->end = end;
+ _range_size_tree_try_insert(*rs_before);
+ } else if (merge_after) {
+ _range_size_tree_rm(*rs_after);
+ rs_after->start = start;
+ _range_size_tree_try_insert(*rs_after);
+ } else {
+ _try_insert_range(start, end, &rs_after);
+ }
+}
+
+void AvlAllocator::_process_range_removal(uint64_t start, uint64_t end,
+ AvlAllocator::range_tree_t::iterator& rs)
+{
+ bool left_over = (rs->start != start);
+ bool right_over = (rs->end != end);
+
+ _range_size_tree_rm(*rs);
+
+ if (left_over && right_over) {
+ auto old_right_end = rs->end;
+ auto insert_pos = rs;
+ ceph_assert(insert_pos != range_tree.end());
+ ++insert_pos;
+ rs->end = start;
+
+ // Insert tail first to be sure insert_pos hasn't been disposed.
+ // This woulnd't dispose rs though since it's out of range_size_tree.
+ // Don't care about a small chance of 'not-the-best-choice-for-removal' case
+ // which might happen if rs has the lowest size.
+ _try_insert_range(end, old_right_end, &insert_pos);
+ _range_size_tree_try_insert(*rs);
+
+ } else if (left_over) {
+ rs->end = start;
+ _range_size_tree_try_insert(*rs);
+ } else if (right_over) {
+ rs->start = end;
+ _range_size_tree_try_insert(*rs);
+ } else {
+ range_tree.erase_and_dispose(rs, dispose_rs{});
+ }
+}
+
+void AvlAllocator::_remove_from_tree(uint64_t start, uint64_t size)
+{
+ uint64_t end = start + size;
+
+ ceph_assert(size != 0);
+ ceph_assert(size <= num_free);
+
+ auto rs = range_tree.find(range_t{start, end}, range_tree.key_comp());
+ /* Make sure we completely overlap with someone */
+ ceph_assert(rs != range_tree.end());
+ ceph_assert(rs->start <= start);
+ ceph_assert(rs->end >= end);
+
+ _process_range_removal(start, end, rs);
+}
+
+void AvlAllocator::_try_remove_from_tree(uint64_t start, uint64_t size,
+ std::function<void(uint64_t, uint64_t, bool)> cb)
+{
+ uint64_t end = start + size;
+
+ ceph_assert(size != 0);
+
+ auto rs = range_tree.find(range_t{ start, end },
+ range_tree.key_comp());
+
+ if (rs == range_tree.end() || rs->start >= end) {
+ cb(start, size, false);
+ return;
+ }
+
+ do {
+
+ auto next_rs = rs;
+ ++next_rs;
+
+ if (start < rs->start) {
+ cb(start, rs->start - start, false);
+ start = rs->start;
+ }
+ auto range_end = std::min(rs->end, end);
+ _process_range_removal(start, range_end, rs);
+ cb(start, range_end - start, true);
+ start = range_end;
+
+ rs = next_rs;
+ } while (rs != range_tree.end() && rs->start < end && start < end);
+ if (start < end) {
+ cb(start, end - start, false);
+ }
+}
+
+int64_t AvlAllocator::_allocate(
+ uint64_t want,
+ uint64_t unit,
+ uint64_t max_alloc_size,
+ int64_t hint, // unused, for now!
+ PExtentVector* extents)
+{
+ uint64_t allocated = 0;
+ while (allocated < want) {
+ uint64_t offset, length;
+ int r = _allocate(std::min(max_alloc_size, want - allocated),
+ unit, &offset, &length);
+ if (r < 0) {
+ // Allocation failed.
+ break;
+ }
+ extents->emplace_back(offset, length);
+ allocated += length;
+ }
+ return allocated ? allocated : -ENOSPC;
+}
+
+int AvlAllocator::_allocate(
+ uint64_t size,
+ uint64_t unit,
+ uint64_t *offset,
+ uint64_t *length)
+{
+ uint64_t max_size = 0;
+ if (auto p = range_size_tree.rbegin(); p != range_size_tree.rend()) {
+ max_size = p->end - p->start;
+ }
+
+ bool force_range_size_alloc = false;
+ if (max_size < size) {
+ if (max_size < unit) {
+ return -ENOSPC;
+ }
+ size = p2align(max_size, unit);
+ ceph_assert(size > 0);
+ force_range_size_alloc = true;
+ }
+
+ const int free_pct = num_free * 100 / num_total;
+ uint64_t start = 0;
+ // If we're running low on space, find a range by size by looking up in the size
+ // sorted tree (best-fit), instead of searching in the area pointed by cursor
+ if (force_range_size_alloc ||
+ max_size < range_size_alloc_threshold ||
+ free_pct < range_size_alloc_free_pct) {
+ start = -1ULL;
+ } else {
+ /*
+ * Find the largest power of 2 block size that evenly divides the
+ * requested size. This is used to try to allocate blocks with similar
+ * alignment from the same area (i.e. same cursor bucket) but it does
+ * not guarantee that other allocations sizes may exist in the same
+ * region.
+ */
+ uint64_t align = size & -size;
+ ceph_assert(align != 0);
+ uint64_t* cursor = &lbas[cbits(align) - 1];
+ start = _pick_block_after(cursor, size, unit);
+ dout(20) << __func__ << " first fit=" << start << " size=" << size << dendl;
+ }
+ if (start == -1ULL) {
+ do {
+ start = _pick_block_fits(size, unit);
+ dout(20) << __func__ << " best fit=" << start << " size=" << size << dendl;
+ if (start != uint64_t(-1ULL)) {
+ break;
+ }
+ // try to collect smaller extents as we could fail to retrieve
+ // that large block due to misaligned extents
+ size = p2align(size >> 1, unit);
+ } while (size >= unit);
+ }
+ if (start == -1ULL) {
+ return -ENOSPC;
+ }
+
+ _remove_from_tree(start, size);
+
+ *offset = start;
+ *length = size;
+ return 0;
+}
+
+void AvlAllocator::_release(const interval_set<uint64_t>& release_set)
+{
+ for (auto p = release_set.begin(); p != release_set.end(); ++p) {
+ const auto offset = p.get_start();
+ const auto length = p.get_len();
+ ldout(cct, 10) << __func__ << std::hex
+ << " offset 0x" << offset
+ << " length 0x" << length
+ << std::dec << dendl;
+ _add_to_tree(offset, length);
+ }
+}
+
+void AvlAllocator::_release(const PExtentVector& release_set) {
+ for (auto& e : release_set) {
+ ldout(cct, 10) << __func__ << std::hex
+ << " offset 0x" << e.offset
+ << " length 0x" << e.length
+ << std::dec << dendl;
+ _add_to_tree(e.offset, e.length);
+ }
+}
+
+void AvlAllocator::_shutdown()
+{
+ range_size_tree.clear();
+ range_tree.clear_and_dispose(dispose_rs{});
+}
+
+AvlAllocator::AvlAllocator(CephContext* cct,
+ int64_t device_size,
+ int64_t block_size,
+ uint64_t max_mem,
+ const std::string& name) :
+ Allocator(name, device_size, block_size),
+ num_total(device_size),
+ block_size(block_size),
+ range_size_alloc_threshold(
+ cct->_conf.get_val<uint64_t>("bluestore_avl_alloc_bf_threshold")),
+ range_size_alloc_free_pct(
+ cct->_conf.get_val<uint64_t>("bluestore_avl_alloc_bf_free_pct")),
+ max_search_count(
+ cct->_conf.get_val<uint64_t>("bluestore_avl_alloc_ff_max_search_count")),
+ max_search_bytes(
+ cct->_conf.get_val<Option::size_t>("bluestore_avl_alloc_ff_max_search_bytes")),
+ range_count_cap(max_mem / sizeof(range_seg_t)),
+ cct(cct)
+{}
+
+AvlAllocator::AvlAllocator(CephContext* cct,
+ int64_t device_size,
+ int64_t block_size,
+ const std::string& name) :
+ AvlAllocator(cct, device_size, block_size, 0 /* max_mem */, name)
+{}
+
+AvlAllocator::~AvlAllocator()
+{
+ shutdown();
+}
+
+int64_t AvlAllocator::allocate(
+ uint64_t want,
+ uint64_t unit,
+ uint64_t max_alloc_size,
+ int64_t hint, // unused, for now!
+ PExtentVector* extents)
+{
+ ldout(cct, 10) << __func__ << std::hex
+ << " want 0x" << want
+ << " unit 0x" << unit
+ << " max_alloc_size 0x" << max_alloc_size
+ << " hint 0x" << hint
+ << std::dec << dendl;
+ ceph_assert(isp2(unit));
+ ceph_assert(want % unit == 0);
+
+ if (max_alloc_size == 0) {
+ max_alloc_size = want;
+ }
+ if (constexpr auto cap = std::numeric_limits<decltype(bluestore_pextent_t::length)>::max();
+ max_alloc_size >= cap) {
+ max_alloc_size = p2align(uint64_t(cap), (uint64_t)block_size);
+ }
+ std::lock_guard l(lock);
+ return _allocate(want, unit, max_alloc_size, hint, extents);
+}
+
+void AvlAllocator::release(const interval_set<uint64_t>& release_set) {
+ std::lock_guard l(lock);
+ _release(release_set);
+}
+
+uint64_t AvlAllocator::get_free()
+{
+ std::lock_guard l(lock);
+ return num_free;
+}
+
+double AvlAllocator::get_fragmentation()
+{
+ std::lock_guard l(lock);
+ return _get_fragmentation();
+}
+
+void AvlAllocator::dump()
+{
+ std::lock_guard l(lock);
+ _dump();
+}
+
+void AvlAllocator::_dump() const
+{
+ ldout(cct, 0) << __func__ << " range_tree: " << dendl;
+ for (auto& rs : range_tree) {
+ ldout(cct, 0) << std::hex
+ << "0x" << rs.start << "~" << rs.end
+ << std::dec
+ << dendl;
+ }
+ ldout(cct, 0) << __func__ << " range_size_tree: " << dendl;
+ for (auto& rs : range_size_tree) {
+ ldout(cct, 0) << std::hex
+ << "0x" << rs.start << "~" << rs.end
+ << std::dec
+ << dendl;
+ }
+}
+
+void AvlAllocator::foreach(
+ std::function<void(uint64_t offset, uint64_t length)> notify)
+{
+ std::lock_guard l(lock);
+ _foreach(notify);
+}
+
+void AvlAllocator::_foreach(
+ std::function<void(uint64_t offset, uint64_t length)> notify) const
+{
+ for (auto& rs : range_tree) {
+ notify(rs.start, rs.end - rs.start);
+ }
+}
+
+void AvlAllocator::init_add_free(uint64_t offset, uint64_t length)
+{
+ if (!length)
+ return;
+ std::lock_guard l(lock);
+ ldout(cct, 10) << __func__ << std::hex
+ << " offset 0x" << offset
+ << " length 0x" << length
+ << std::dec << dendl;
+ _add_to_tree(offset, length);
+}
+
+void AvlAllocator::init_rm_free(uint64_t offset, uint64_t length)
+{
+ if (!length)
+ return;
+ std::lock_guard l(lock);
+ ldout(cct, 10) << __func__ << std::hex
+ << " offset 0x" << offset
+ << " length 0x" << length
+ << std::dec << dendl;
+ _remove_from_tree(offset, length);
+}
+
+void AvlAllocator::shutdown()
+{
+ std::lock_guard l(lock);
+ _shutdown();
+}