From 2bd612fd197232645e5617d8041949912e3e7918 Mon Sep 17 00:00:00 2001 From: Eugen Wissner Date: Wed, 12 Jul 2017 09:30:07 +0200 Subject: [PATCH] Make MmapPool allocations pure --- source/tanya/memory/mmappool.d | 124 ++++++++++++++++++++------------- 1 file changed, 77 insertions(+), 47 deletions(-) diff --git a/source/tanya/memory/mmappool.d b/source/tanya/memory/mmappool.d index 092b477..7e8dac9 100644 --- a/source/tanya/memory/mmappool.d +++ b/source/tanya/memory/mmappool.d @@ -18,14 +18,61 @@ import tanya.memory.allocator; version (Posix) { - import core.stdc.errno; - import core.sys.posix.sys.mman; import core.sys.posix.unistd; + + extern (C) + private void* mmap(void* addr, + size_t len, + int prot, + int flags, + int fd, + off_t offset) pure nothrow @system @nogc; + + extern (C) + private int munmap(void* addr, size_t len) pure nothrow @system @nogc; + + private void* mapMemory(const size_t len) pure nothrow @system @nogc + { + void* p = mmap(null, + len, + 0x01 | 0x02, // PROT_READ | PROT_WRITE + 0x0002 | 0x1000, // MAP_PRIVATE | MAP_ANON + -1, + 0); + return p is (cast(void*) -1) ? null : p; + } + + private bool unmapMemory(shared void* addr, const size_t len) + pure nothrow @system @nogc + { + return munmap(cast(void*) addr, len) == 0; + } } else version (Windows) { - import core.sys.windows.winbase; - import core.sys.windows.windows; + import core.sys.windows.winbase : GetSystemInfo, SYSTEM_INFO; + + extern (Windows) + private void* VirtualAlloc(void*, size_t, uint, uint) + pure nothrow @system @nogc; + + extern (Windows) + private int VirtualFree(void* addr, size_t len, uint) + pure nothrow @system @nogc; + + private void* mapMemory(const size_t len) pure nothrow @system @nogc + { + return VirtualAlloc(null, + len, + 0x00001000, // MEM_COMMIT + 0x04); // PAGE_READWRITE + } + + private bool unmapMemory(shared void* addr, const size_t len) + pure nothrow @system @nogc + { + return VirtualFree(cast(void*) addr, 0, 0x8000) == 0; + } } /** @@ -78,7 +125,7 @@ final class MmapPool : Allocator * * Returns: Pointer to the new allocated memory. */ - void[] allocate(const size_t size) shared nothrow @nogc + void[] allocate(const size_t size) shared pure nothrow @nogc { if (size == 0) { @@ -137,7 +184,7 @@ final class MmapPool : Allocator * * Returns: Data the block points to or $(D_KEYWORD null). */ - private void* findBlock(const ref size_t size) shared nothrow @nogc + private void* findBlock(const ref size_t size) shared pure nothrow @nogc { Block block1; RegionLoop: for (auto r = head; r !is null; r = r.next) @@ -197,7 +244,7 @@ final class MmapPool : Allocator * * Returns: Whether the deallocation was successful. */ - bool deallocate(void[] p) shared nothrow @nogc + bool deallocate(void[] p) shared pure nothrow @nogc { if (p.ptr is null) { @@ -219,14 +266,7 @@ final class MmapPool : Allocator { block.region.next.prev = block.region.prev; } - version (Posix) - { - return munmap(cast(void*) block.region, block.region.size) == 0; - } - version (Windows) - { - return VirtualFree(cast(void*) block.region, 0, MEM_RELEASE) == 0; - } + return unmapMemory(block.region, block.region.size); } // Merge blocks if neigbours are free. if (block.next !is null && block.next.free) @@ -271,7 +311,7 @@ final class MmapPool : Allocator * Returns: $(D_KEYWORD true) if successful, $(D_KEYWORD false) otherwise. */ bool reallocateInPlace(ref void[] p, const size_t size) - shared nothrow @nogc + pure shared nothrow @nogc { if (p is null || size == 0) { @@ -368,7 +408,7 @@ final class MmapPool : Allocator * * Returns: Whether the reallocation was successful. */ - bool reallocate(ref void[] p, const size_t size) shared nothrow @nogc + bool reallocate(ref void[] p, const size_t size) shared pure nothrow @nogc { if (size == 0) { @@ -441,17 +481,17 @@ final class MmapPool : Allocator // Get system dependend page size. version (Posix) { - pageSize = sysconf(_SC_PAGE_SIZE); - if (pageSize < 65536) + pageSize_ = sysconf(_SC_PAGE_SIZE); + if (pageSize_ < 65536) { - pageSize = pageSize * 65536 / pageSize; + pageSize_ = pageSize_ * 65536 / pageSize_; } } else version (Windows) { SYSTEM_INFO si; GetSystemInfo(&si); - pageSize = si.dwPageSize; + pageSize_ = si.dwPageSize; } const instanceSize = addAlignment(__traits(classInstanceSize, @@ -485,36 +525,18 @@ final class MmapPool : Allocator * Returns: A pointer to the data. */ private static void* initializeRegion(const size_t size, ref Region head) - nothrow @nogc + pure nothrow @nogc { const regionSize = calculateRegionSize(size); if (regionSize < size) { return null; } - version (Posix) + + void* p = mapMemory(regionSize); + if (p is null) { - void* p = mmap(null, - regionSize, - PROT_READ | PROT_WRITE, - MAP_PRIVATE | MAP_ANON, - -1, - 0); - if (p is MAP_FAILED) - { - return null; - } - } - else version (Windows) - { - void* p = VirtualAlloc(null, - regionSize, - MEM_COMMIT, - PAGE_READWRITE); - if (p is null) - { - return null; - } + return null; } Region region = cast(Region) p; @@ -552,7 +574,7 @@ final class MmapPool : Allocator return data; } - private void* initializeRegion(const size_t size) shared nothrow @nogc + private void* initializeRegion(const size_t size) shared pure nothrow @nogc { return initializeRegion(size, head); } @@ -575,7 +597,7 @@ final class MmapPool : Allocator * Returns: Minimum region size (a multiple of $(D_PSYMBOL pageSize)). */ private static size_t calculateRegionSize(const size_t x) - nothrow @safe @nogc + pure nothrow @safe @nogc { return (x + RegionEntry.sizeof + BlockEntry.sizeof * 2) / pageSize * pageSize + pageSize; @@ -594,10 +616,18 @@ final class MmapPool : Allocator assert(MmapPool.instance.alignment == MmapPool.alignment_); } + private static @property size_t pageSize() pure nothrow @trusted @nogc + { + const pageSize = function size_t() nothrow @safe @nogc { + return pageSize_; + }; + return (cast(size_t function() pure nothrow @safe @nogc) pageSize)(); + } + private enum uint alignment_ = 8; private shared static MmapPool instance_; - private shared static size_t pageSize; + private shared static size_t pageSize_; private shared struct RegionEntry {