diff options
author | Jacques Lucke <jacques@blender.org> | 2022-04-07 20:28:41 +0300 |
---|---|---|
committer | Jacques Lucke <jacques@blender.org> | 2022-04-07 20:28:41 +0300 |
commit | a5beca7ba0daaca81805dbbf8857378a5bde6414 (patch) | |
tree | 6706ff6ed48e3e9bc5288d40170f711cf2d7617b /source/blender/blenlib | |
parent | 67c42e7f034aad2564d8cde1a9901d9629527daa (diff) |
BLI: inline fast path of IndexRange::as_span
This frequently showed up in profiling but shouldn't.
This also updates the code to use atomics for more correctness and
adds multi-threading for better performance.
Diffstat (limited to 'source/blender/blenlib')
-rw-r--r-- | source/blender/blenlib/BLI_index_range.hh | 7 | ||||
-rw-r--r-- | source/blender/blenlib/BLI_span.hh | 12 | ||||
-rw-r--r-- | source/blender/blenlib/intern/BLI_index_range.cc | 45 |
3 files changed, 42 insertions, 22 deletions
diff --git a/source/blender/blenlib/BLI_index_range.hh b/source/blender/blenlib/BLI_index_range.hh index 85f2c83364b..7d5c2400bba 100644 --- a/source/blender/blenlib/BLI_index_range.hh +++ b/source/blender/blenlib/BLI_index_range.hh @@ -39,6 +39,7 @@ */ #include <algorithm> +#include <atomic> #include <cmath> #include <iostream> @@ -288,6 +289,12 @@ class IndexRange { stream << "[" << range.start() << ", " << range.one_after_last() << ")"; return stream; } + + private: + static std::atomic<int64_t> s_current_array_size; + static std::atomic<int64_t *> s_current_array; + + Span<int64_t> as_span_internal() const; }; } // namespace blender diff --git a/source/blender/blenlib/BLI_span.hh b/source/blender/blenlib/BLI_span.hh index 9ab096094de..0f3fcea1270 100644 --- a/source/blender/blenlib/BLI_span.hh +++ b/source/blender/blenlib/BLI_span.hh @@ -722,4 +722,16 @@ template<typename T> class MutableSpan { } }; +/** This is defined here, because in `BLI_index_range.hh` `Span` is not yet defined. */ +inline Span<int64_t> IndexRange::as_span() const +{ + const int64_t min_required_size = start_ + size_; + const int64_t current_array_size = s_current_array_size.load(std::memory_order_acquire); + const int64_t *current_array = s_current_array.load(std::memory_order_acquire); + if (min_required_size <= current_array_size) { + return Span<int64_t>(current_array + start_, size_); + } + return this->as_span_internal(); +} + } /* namespace blender */ diff --git a/source/blender/blenlib/intern/BLI_index_range.cc b/source/blender/blenlib/intern/BLI_index_range.cc index 346f55d9405..398228ab461 100644 --- a/source/blender/blenlib/intern/BLI_index_range.cc +++ b/source/blender/blenlib/intern/BLI_index_range.cc @@ -1,46 +1,47 @@ /* SPDX-License-Identifier: GPL-2.0-or-later */ -#include <atomic> #include <mutex> #include "BLI_array.hh" #include "BLI_index_range.hh" #include "BLI_span.hh" +#include "BLI_task.hh" #include "BLI_vector.hh" namespace blender { static RawVector<RawArray<int64_t, 0>> arrays; -static int64_t current_array_size = 0; -static int64_t *current_array = nullptr; static std::mutex current_array_mutex; +std::atomic<int64_t> IndexRange::s_current_array_size = 0; +std::atomic<int64_t *> IndexRange::s_current_array = nullptr; -Span<int64_t> IndexRange::as_span() const +Span<int64_t> IndexRange::as_span_internal() const { int64_t min_required_size = start_ + size_; - if (min_required_size <= current_array_size) { - return Span<int64_t>(current_array + start_, size_); - } - std::lock_guard<std::mutex> lock(current_array_mutex); - if (min_required_size <= current_array_size) { - return Span<int64_t>(current_array + start_, size_); + /* Double checked lock. */ + if (min_required_size <= s_current_array_size) { + return Span<int64_t>(s_current_array + start_, size_); } - int64_t new_size = std::max<int64_t>(1000, power_of_2_max_u(min_required_size)); - RawArray<int64_t, 0> new_array(new_size); - for (int64_t i = 0; i < new_size; i++) { - new_array[i] = i; - } - arrays.append(std::move(new_array)); - - current_array = arrays.last().data(); - std::atomic_thread_fence(std::memory_order_seq_cst); - current_array_size = new_size; - - return Span<int64_t>(current_array + start_, size_); + /* Isolate, because a mutex is locked. */ + threading::isolate_task([&]() { + int64_t new_size = std::max<int64_t>(1000, power_of_2_max_u(min_required_size)); + RawArray<int64_t, 0> new_array(new_size); + threading::parallel_for(IndexRange(new_size), 4096, [&](const IndexRange range) { + for (const int64_t i : range) { + new_array[i] = i; + } + }); + arrays.append(std::move(new_array)); + + s_current_array.store(arrays.last().data(), std::memory_order_release); + s_current_array_size.store(new_size, std::memory_order_release); + }); + + return Span<int64_t>(s_current_array + start_, size_); } } // namespace blender |