-/* -----------------------------------------------------------------------------
- *
- * (c) The GHC Team 1998-1999
- *
- * MegaBlock Allocator Interface. This file contains all the dirty
- * architecture-dependent hackery required to get a chunk of aligned
- * memory from the operating system.
- *
- * ---------------------------------------------------------------------------*/
-
-/* This is non-posix compliant. */
-/* #include "PosixSource.h" */
-
-#include "Rts.h"
-#include "RtsUtils.h"
-#include "RtsFlags.h"
-#include "MBlock.h"
-#include "BlockAlloc.h"
-
-#ifdef HAVE_STDLIB_H
-#include <stdlib.h>
-#endif
-#ifdef HAVE_STRING_H
-#include <string.h>
-#endif
-#ifdef HAVE_UNISTD_H
-#include <unistd.h>
-#endif
-#ifdef HAVE_SYS_TYPES_H
-#include <sys/types.h>
-#endif
-#ifndef mingw32_HOST_OS
-# ifdef HAVE_SYS_MMAN_H
-# include <sys/mman.h>
-# endif
-#endif
-#ifdef HAVE_FCNTL_H
-#include <fcntl.h>
-#endif
-#if HAVE_WINDOWS_H
-#include <windows.h>
-#endif
-#if darwin_HOST_OS
-#include <mach/vm_map.h>
-#endif
-
-#include <errno.h>
-
-lnat mblocks_allocated = 0;
-
-/* -----------------------------------------------------------------------------
- The MBlock Map: provides our implementation of HEAP_ALLOCED()
- -------------------------------------------------------------------------- */
-
-#if SIZEOF_VOID_P == 4
-StgWord8 mblock_map[MBLOCK_MAP_SIZE]; // initially all zeros
-#elif SIZEOF_VOID_P == 8
-static MBlockMap dummy_mblock_map;
-MBlockMap *mblock_cache = &dummy_mblock_map;
-int mblock_map_count = 0;
-MBlockMap **mblock_maps = NULL;
-
-static MBlockMap *
-findMBlockMap(void *p)
-{
- int i;
- StgWord32 hi = (StgWord32) (((StgWord)p) >> 32);
- for( i = 0; i < mblock_map_count; i++ )
- {
- if(mblock_maps[i]->addrHigh32 == hi)
- {
- return mblock_maps[i];
- }
- }
- return NULL;
-}
-
-StgBool
-slowIsHeapAlloced(void *p)
-{
- MBlockMap *map = findMBlockMap(p);
- if(map)
- {
- mblock_cache = map;
- return map->mblocks[MBLOCK_MAP_ENTRY(p)];
- }
- else
- return 0;
-}
-#endif
-
-static void
-markHeapAlloced(void *p)
-{
-#if SIZEOF_VOID_P == 4
- mblock_map[MBLOCK_MAP_ENTRY(p)] = 1;
-#elif SIZEOF_VOID_P == 8
- MBlockMap *map = findMBlockMap(p);
- if(map == NULL)
- {
- mblock_map_count++;
- mblock_maps = realloc(mblock_maps,
- sizeof(MBlockMap*) * mblock_map_count);
- map = mblock_maps[mblock_map_count-1] = calloc(1,sizeof(MBlockMap));
- map->addrHigh32 = (StgWord32) (((StgWord)p) >> 32);
- }
- map->mblocks[MBLOCK_MAP_ENTRY(p)] = 1;
- mblock_cache = map;
-#endif
-}
-
-/* -----------------------------------------------------------------------------
- Allocate new mblock(s)
- -------------------------------------------------------------------------- */
-
-void *
-getMBlock(void)
-{
- return getMBlocks(1);
-}
-
-/* -----------------------------------------------------------------------------
- The mmap() method
-
- On Unix-like systems, we use mmap() to allocate our memory. We
- want memory in chunks of MBLOCK_SIZE, and aligned on an MBLOCK_SIZE
- boundary. The mmap() interface doesn't give us this level of
- control, so we have to use some heuristics.
-
- In the general case, if we want a block of n megablocks, then we
- allocate n+1 and trim off the slop from either side (using
- munmap()) to get an aligned chunk of size n. However, the next
- time we'll try to allocate directly after the previously allocated
- chunk, on the grounds that this is aligned and likely to be free.
- If it turns out that we were wrong, we have to munmap() and try
- again using the general method.
-
- Note on posix_memalign(): this interface is available on recent
- systems and appears to provide exactly what we want. However, it
- turns out not to be as good as our mmap() implementation, because
- it wastes extra space (using double the address space, in a test on
- x86_64/Linux). The problem seems to be that posix_memalign()
- returns memory that can be free()'d, so the library must store
- extra information along with the allocated block, thus messing up
- the alignment. Hence, we don't use posix_memalign() for now.
-
- -------------------------------------------------------------------------- */
-
-#if !defined(mingw32_HOST_OS) && !defined(cygwin32_HOST_OS)
-
-// A wrapper around mmap(), to abstract away from OS differences in
-// the mmap() interface.
-
-static void *
-my_mmap (void *addr, lnat size)
-{
- void *ret;
-
-#if defined(solaris2_HOST_OS) || defined(irix_HOST_OS)
- {
- int fd = open("/dev/zero",O_RDONLY);
- ret = mmap(addr, size, PROT_READ | PROT_WRITE, MAP_PRIVATE, fd, 0);
- close(fd);
- }
-#elif hpux_HOST_OS
- ret = mmap(addr, size, PROT_READ | PROT_WRITE,
- MAP_ANONYMOUS | MAP_PRIVATE, -1, 0);
-#elif darwin_HOST_OS
- // Without MAP_FIXED, Apple's mmap ignores addr.
- // With MAP_FIXED, it overwrites already mapped regions, whic
- // mmap(0, ... MAP_FIXED ...) is worst of all: It unmaps the program text
- // and replaces it with zeroes, causing instant death.
- // This behaviour seems to be conformant with IEEE Std 1003.1-2001.
- // Let's just use the underlying Mach Microkernel calls directly,
- // they're much nicer.
-
- kern_return_t err;
- ret = addr;
- if(addr) // try to allocate at adress
- err = vm_allocate(mach_task_self(),(vm_address_t*) &ret, size, FALSE);
- if(!addr || err) // try to allocate anywhere
- err = vm_allocate(mach_task_self(),(vm_address_t*) &ret, size, TRUE);
-
- if(err) {
- // don't know what the error codes mean exactly, assume it's
- // not our problem though.
- errorBelch("memory allocation failed (requested %lu bytes)", size);
- stg_exit(EXIT_FAILURE);
- } else {
- vm_protect(mach_task_self(),ret,size,FALSE,VM_PROT_READ|VM_PROT_WRITE);
- }
-#else
- ret = mmap(addr, size, PROT_READ | PROT_WRITE | PROT_EXEC,
- MAP_ANON | MAP_PRIVATE, -1, 0);
-#endif
-
- if (ret == (void *)-1) {
- if (errno == ENOMEM ||
- (errno == EINVAL && sizeof(void*)==4 && size >= 0xc0000000)) {
- // If we request more than 3Gig, then we get EINVAL
- // instead of ENOMEM (at least on Linux).
- errorBelch("out of memory (requested %lu bytes)", size);
- stg_exit(EXIT_FAILURE);
- } else {
- barf("getMBlock: mmap: %s", strerror(errno));
- }
- }
-
- return ret;
-}
-
-// Implements the general case: allocate a chunk of memory of 'size'
-// mblocks.
-
-static void *
-gen_map_mblocks (lnat size)
-{
- int slop;
- void *ret;
-
- // Try to map a larger block, and take the aligned portion from
- // it (unmap the rest).
- size += MBLOCK_SIZE;
- ret = my_mmap(0, size);
-
- // unmap the slop bits around the chunk we allocated
- slop = (W_)ret & MBLOCK_MASK;
-
- if (munmap(ret, MBLOCK_SIZE - slop) == -1) {
- barf("gen_map_mblocks: munmap failed");
- }
- if (slop > 0 && munmap(ret+size-slop, slop) == -1) {
- barf("gen_map_mblocks: munmap failed");
- }
-
- // ToDo: if we happened to get an aligned block, then don't
- // unmap the excess, just use it. For this to work, you
- // need to keep in mind the following:
- // * Calling my_mmap() with an 'addr' arg pointing to
- // already my_mmap()ed space is OK and won't fail.
- // * If my_mmap() can't satisfy the request at the
- // given 'next_request' address in getMBlocks(), that
- // you unmap the extra mblock mmap()ed here (or simply
- // satisfy yourself that the slop introduced isn't worth
- // salvaging.)
- //
-
- // next time, try after the block we just got.
- ret += MBLOCK_SIZE - slop;
- return ret;
-}
-
-
-// The external interface: allocate 'n' mblocks, and return the
-// address.
-
-void *
-getMBlocks(nat n)
-{
- static caddr_t next_request = (caddr_t)HEAP_BASE;
- caddr_t ret;
- lnat size = MBLOCK_SIZE * n;
- nat i;
-
- if (next_request == 0) {
- // use gen_map_mblocks the first time.
- ret = gen_map_mblocks(size);
- } else {
- ret = my_mmap(next_request, size);
-
- if (((W_)ret & MBLOCK_MASK) != 0) {
- // misaligned block!
-#if 0 // defined(DEBUG)
- errorBelch("warning: getMBlock: misaligned block %p returned when allocating %d megablock(s) at %p", ret, n, next_request);
-#endif
-
- // unmap this block...
- if (munmap(ret, size) == -1) {
- barf("getMBlock: munmap failed");
- }
- // and do it the hard way
- ret = gen_map_mblocks(size);
- }
- }
-
- // Next time, we'll try to allocate right after the block we just got.
- // ToDo: check that we haven't already grabbed the memory at next_request
- next_request = ret + size;
-
- IF_DEBUG(gc,debugBelch("Allocated %d megablock(s) at %p\n",n,ret));
-
- // fill in the table
- for (i = 0; i < n; i++) {
- markHeapAlloced( ret + i * MBLOCK_SIZE );
- }
-
- mblocks_allocated += n;
-
- return ret;
-}
-
-void
-freeAllMBlocks(void)
-{
- /* XXX Do something here */
-}
-
-#else /* defined(mingw32_HOST_OS) || defined(cygwin32_HOST_OS) */
-
-/*
- On Win32 platforms we make use of the two-phased virtual memory API
- to allocate mega blocks. We proceed as follows:
-
- Reserve a large chunk of VM (256M at the time, or what the user asked
- for via the -M option), but don't supply a base address that's aligned on
- a MB boundary. Instead we round up to the nearest mblock from the chunk of
- VM we're handed back from the OS (at the moment we just leave the 'slop' at
- the beginning of the reserved chunk unused - ToDo: reuse it .)
-
- Reserving memory doesn't allocate physical storage (not even in the
- page file), this is done later on by committing pages (or mega-blocks in
- our case).
-*/
-
-static char* base_non_committed = (char*)0;
-static char* end_non_committed = (char*)0;
-
-static void *membase;
-
-/* Default is to reserve 256M of VM to minimise the slop cost. */
-#define SIZE_RESERVED_POOL ( 256 * 1024 * 1024 )
-
-/* Number of bytes reserved */
-static unsigned long size_reserved_pool = SIZE_RESERVED_POOL;
-
-void *
-getMBlocks(nat n)
-{
- static char* base_mblocks = (char*)0;
- static char* next_request = (char*)0;
- void* ret = (void*)0;
- nat i;
-
- lnat size = MBLOCK_SIZE * n;
-
- if ( (base_non_committed == 0) || (next_request + size > end_non_committed) ) {
- if (base_non_committed) {
- /* Tacky, but if no user-provided -M option is in effect,
- * set it to the default (==256M) in time for the heap overflow PSA.
- */
- if (RtsFlags.GcFlags.maxHeapSize == 0) {
- RtsFlags.GcFlags.maxHeapSize = size_reserved_pool / BLOCK_SIZE;
- }
- heapOverflow();
- }
- if (RtsFlags.GcFlags.maxHeapSize != 0) {
- size_reserved_pool = BLOCK_SIZE * RtsFlags.GcFlags.maxHeapSize;
- if (size_reserved_pool < MBLOCK_SIZE) {
- size_reserved_pool = 2*MBLOCK_SIZE;
- }
- }
- base_non_committed = VirtualAlloc ( NULL
- , size_reserved_pool
- , MEM_RESERVE
- , PAGE_READWRITE
- );
- membase = base_non_committed;
- if ( base_non_committed == 0 ) {
- errorBelch("getMBlocks: VirtualAlloc MEM_RESERVE %lu failed with: %ld\n", size_reserved_pool, GetLastError());
- ret=(void*)-1;
- } else {
- end_non_committed = (char*)base_non_committed + (unsigned long)size_reserved_pool;
- /* The returned pointer is not aligned on a mega-block boundary. Make it. */
- base_mblocks = (char*)((unsigned long)base_non_committed & (unsigned long)~MBLOCK_MASK) + MBLOCK_SIZE;
-# if 0
- debugBelch("getMBlocks: Dropping %d bytes off of 256M chunk\n",
- (unsigned)base_mblocks - (unsigned)base_non_committed);
-# endif
-
- if ( ((char*)base_mblocks + size) > end_non_committed ) {
- debugBelch("getMBlocks: oops, committed too small a region to start with.");
- ret=(void*)-1;
- } else {
- next_request = base_mblocks;
- }
- }
- }
- /* Commit the mega block(s) to phys mem */
- if ( ret != (void*)-1 ) {
- ret = VirtualAlloc(next_request, size, MEM_COMMIT, PAGE_READWRITE);
- if (ret == NULL) {
- debugBelch("getMBlocks: VirtualAlloc MEM_COMMIT %lu failed with: %ld\n", size, GetLastError());
- ret=(void*)-1;
- }
- }
-
- if (((W_)ret & MBLOCK_MASK) != 0) {
- barf("getMBlocks: misaligned block returned");
- }
-
- if (ret == (void*)-1) {
- barf("getMBlocks: unknown memory allocation failure on Win32.");
- }
-
- IF_DEBUG(gc,debugBelch("Allocated %d megablock(s) at 0x%x\n",n,(nat)ret));
- next_request = (char*)next_request + size;
-
- mblocks_allocated += n;
-
- // fill in the table
- for (i = 0; i < n; i++) {
- markHeapAlloced( ret + i * MBLOCK_SIZE );
- }
-
- return ret;
-}
-
-void
-freeAllMBlocks(void)
-{
- BOOL rc;
-
- rc = VirtualFree(membase, 0, MEM_RELEASE);
-
- if (rc == FALSE) {
- debugBelch("freeAllMBlocks: VirtualFree failed with: %ld\n", GetLastError());
- }
-}
-
-/* Hand back the physical memory that is allocated to a mega-block.
- ToDo: chain the released mega block onto some list so that
- getMBlocks() can get at it.
-
- Currently unused.
-*/
-#if 0
-void
-freeMBlock(void* p, nat n)
-{
- BOOL rc;
-
- rc = VirtualFree(p, n * MBLOCK_SIZE , MEM_DECOMMIT );
-
- if (rc == FALSE) {
-# ifdef DEBUG
- debugBelch("freeMBlocks: VirtualFree failed with: %d\n", GetLastError());
-# endif
- }
-
-}
-#endif
-
-#endif