//===---------------------- rpmalloc.h ------------------*- C -*-=============//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
// This library provides a cross-platform lock free thread caching malloc
// implementation in C11.
//
//===----------------------------------------------------------------------===//
#pragma once
#include <stddef.h>
#ifdef __cplusplus
extern "C" {
#endif
#if defined(__clang__) || defined(__GNUC__)
#define RPMALLOC_EXPORT __attribute__((visibility("default")))
#define RPMALLOC_ALLOCATOR
#if (defined(__clang_major__) && (__clang_major__ < 4)) || \
(defined(__GNUC__) && defined(ENABLE_PRELOAD) && ENABLE_PRELOAD)
#define RPMALLOC_ATTRIB_MALLOC
#define RPMALLOC_ATTRIB_ALLOC_SIZE(size)
#define RPMALLOC_ATTRIB_ALLOC_SIZE2(count, size)
#else
#define RPMALLOC_ATTRIB_MALLOC __attribute__((__malloc__))
#define RPMALLOC_ATTRIB_ALLOC_SIZE(size) __attribute__((alloc_size(size)))
#define RPMALLOC_ATTRIB_ALLOC_SIZE2(count, size) \
__attribute__((alloc_size(count, size)))
#endif
#define RPMALLOC_CDECL
#elif defined(_MSC_VER)
#define RPMALLOC_EXPORT
#define RPMALLOC_ALLOCATOR __declspec(allocator) __declspec(restrict)
#define RPMALLOC_ATTRIB_MALLOC
#define RPMALLOC_ATTRIB_ALLOC_SIZE(size)
#define RPMALLOC_ATTRIB_ALLOC_SIZE2(count, size)
#define RPMALLOC_CDECL __cdecl
#else
#define RPMALLOC_EXPORT
#define RPMALLOC_ALLOCATOR
#define RPMALLOC_ATTRIB_MALLOC
#define RPMALLOC_ATTRIB_ALLOC_SIZE(size)
#define RPMALLOC_ATTRIB_ALLOC_SIZE2(count, size)
#define RPMALLOC_CDECL
#endif
//! Define RPMALLOC_CONFIGURABLE to enable configuring sizes. Will introduce
// a very small overhead due to some size calculations not being compile time
// constants
#ifndef RPMALLOC_CONFIGURABLE
#define RPMALLOC_CONFIGURABLE 0
#endif
//! Define RPMALLOC_FIRST_CLASS_HEAPS to enable heap based API (rpmalloc_heap_*
//! functions).
// Will introduce a very small overhead to track fully allocated spans in heaps
#ifndef RPMALLOC_FIRST_CLASS_HEAPS
#define RPMALLOC_FIRST_CLASS_HEAPS 0
#endif
//! Flag to rpaligned_realloc to not preserve content in reallocation
#define RPMALLOC_NO_PRESERVE 1
//! Flag to rpaligned_realloc to fail and return null pointer if grow cannot be
//! done in-place,
// in which case the original pointer is still valid (just like a call to
// realloc which failes to allocate a new block).
#define RPMALLOC_GROW_OR_FAIL 2
typedef struct rpmalloc_global_statistics_t {
//! Current amount of virtual memory mapped, all of which might not have been
//! committed (only if ENABLE_STATISTICS=1)
size_t mapped;
//! Peak amount of virtual memory mapped, all of which might not have been
//! committed (only if ENABLE_STATISTICS=1)
size_t mapped_peak;
//! Current amount of memory in global caches for small and medium sizes
//! (<32KiB)
size_t cached;
//! Current amount of memory allocated in huge allocations, i.e larger than
//! LARGE_SIZE_LIMIT which is 2MiB by default (only if ENABLE_STATISTICS=1)
size_t huge_alloc;
//! Peak amount of memory allocated in huge allocations, i.e larger than
//! LARGE_SIZE_LIMIT which is 2MiB by default (only if ENABLE_STATISTICS=1)
size_t huge_alloc_peak;
//! Total amount of memory mapped since initialization (only if
//! ENABLE_STATISTICS=1)
size_t mapped_total;
//! Total amount of memory unmapped since initialization (only if
//! ENABLE_STATISTICS=1)
size_t unmapped_total;
} rpmalloc_global_statistics_t;
typedef struct rpmalloc_thread_statistics_t {
//! Current number of bytes available in thread size class caches for small
//! and medium sizes (<32KiB)
size_t sizecache;
//! Current number of bytes available in thread span caches for small and
//! medium sizes (<32KiB)
size_t spancache;
//! Total number of bytes transitioned from thread cache to global cache (only
//! if ENABLE_STATISTICS=1)
size_t thread_to_global;
//! Total number of bytes transitioned from global cache to thread cache (only
//! if ENABLE_STATISTICS=1)
size_t global_to_thread;
//! Per span count statistics (only if ENABLE_STATISTICS=1)
struct {
//! Currently used number of spans
size_t current;
//! High water mark of spans used
size_t peak;
//! Number of spans transitioned to global cache
size_t to_global;
//! Number of spans transitioned from global cache
size_t from_global;
//! Number of spans transitioned to thread cache
size_t to_cache;
//! Number of spans transitioned from thread cache
size_t from_cache;
//! Number of spans transitioned to reserved state
size_t to_reserved;
//! Number of spans transitioned from reserved state
size_t from_reserved;
//! Number of raw memory map calls (not hitting the reserve spans but
//! resulting in actual OS mmap calls)
size_t map_calls;
} span_use[64];
//! Per size class statistics (only if ENABLE_STATISTICS=1)
struct {
//! Current number of allocations
size_t alloc_current;
//! Peak number of allocations
size_t alloc_peak;
//! Total number of allocations
size_t alloc_total;
//! Total number of frees
size_t free_total;
//! Number of spans transitioned to cache
size_t spans_to_cache;
//! Number of spans transitioned from cache
size_t spans_from_cache;
//! Number of spans transitioned from reserved state
size_t spans_from_reserved;
//! Number of raw memory map calls (not hitting the reserve spans but
//! resulting in actual OS mmap calls)
size_t map_calls;
} size_use[128];
} rpmalloc_thread_statistics_t;
typedef struct rpmalloc_config_t {
//! Map memory pages for the given number of bytes. The returned address MUST
//! be
// aligned to the rpmalloc span size, which will always be a power of two.
// Optionally the function can store an alignment offset in the offset
// variable in case it performs alignment and the returned pointer is offset
// from the actual start of the memory region due to this alignment. The
// alignment offset will be passed to the memory unmap function. The
// alignment offset MUST NOT be larger than 65535 (storable in an uint16_t),
// if it is you must use natural alignment to shift it into 16 bits. If you
// set a memory_map function, you must also set a memory_unmap function or
// else the default implementation will be used for both. This function must
// be thread safe, it can be called by multiple threads simultaneously.
void *(*memory_map)(size_t size, size_t *offset);
//! Unmap the memory pages starting at address and spanning the given number
//! of bytes.
// If release is set to non-zero, the unmap is for an entire span range as
// returned by a previous call to memory_map and that the entire range should
// be released. The release argument holds the size of the entire span range.
// If release is set to 0, the unmap is a partial decommit of a subset of the
// mapped memory range. If you set a memory_unmap function, you must also set
// a memory_map function or else the default implementation will be used for
// both. This function must be thread safe, it can be called by multiple
// threads simultaneously.
void (*memory_unmap)(void *address, size_t size, size_t offset,
size_t release);
//! Called when an assert fails, if asserts are enabled. Will use the standard
//! assert()
// if this is not set.
void (*error_callback)(const char *message);
//! Called when a call to map memory pages fails (out of memory). If this
//! callback is
// not set or returns zero the library will return a null pointer in the
// allocation call. If this callback returns non-zero the map call will be
// retried. The argument passed is the number of bytes that was requested in
// the map call. Only used if the default system memory map function is used
// (memory_map callback is not set).
int (*map_fail_callback)(size_t size);
//! Size of memory pages. The page size MUST be a power of two. All memory
//! mapping
// requests to memory_map will be made with size set to a multiple of the
// page size. Used if RPMALLOC_CONFIGURABLE is defined to 1, otherwise system
// page size is used.
size_t page_size;
//! Size of a span of memory blocks. MUST be a power of two, and in
//! [4096,262144]
// range (unless 0 - set to 0 to use the default span size). Used if
// RPMALLOC_CONFIGURABLE is defined to 1.
size_t span_size;
//! Number of spans to map at each request to map new virtual memory blocks.
//! This can
// be used to minimize the system call overhead at the cost of virtual memory
// address space. The extra mapped pages will not be written until actually
// used, so physical committed memory should not be affected in the default
// implementation. Will be aligned to a multiple of spans that match memory
// page size in case of huge pages.
size_t span_map_count;
//! Enable use of large/huge pages. If this flag is set to non-zero and page
//! size is
// zero, the allocator will try to enable huge pages and auto detect the
// configuration. If this is set to non-zero and page_size is also non-zero,
// the allocator will assume huge pages have been configured and enabled
// prior to initializing the allocator. For Windows, see
// https://docs.microsoft.com/en-us/windows/desktop/memory/large-page-support
// For Linux, see https://www.kernel.org/doc/Documentation/vm/hugetlbpage.txt
int enable_huge_pages;
//! Respectively allocated pages and huge allocated pages names for systems
// supporting it to be able to distinguish among anonymous regions.
const char *page_name;
const char *huge_page_name;
} rpmalloc_config_t;
//! Initialize allocator with default configuration
RPMALLOC_EXPORT int rpmalloc_initialize(void);
//! Initialize allocator with given configuration
RPMALLOC_EXPORT int rpmalloc_initialize_config(const rpmalloc_config_t *config);
//! Get allocator configuration
RPMALLOC_EXPORT const rpmalloc_config_t *rpmalloc_config(void);
//! Finalize allocator
RPMALLOC_EXPORT void rpmalloc_finalize(void);
//! Initialize allocator for calling thread
RPMALLOC_EXPORT void rpmalloc_thread_initialize(void);
//! Finalize allocator for calling thread
RPMALLOC_EXPORT void rpmalloc_thread_finalize(int release_caches);
//! Perform deferred deallocations pending for the calling thread heap
RPMALLOC_EXPORT void rpmalloc_thread_collect(void);
//! Query if allocator is initialized for calling thread
RPMALLOC_EXPORT int rpmalloc_is_thread_initialized(void);
//! Get per-thread statistics
RPMALLOC_EXPORT void
rpmalloc_thread_statistics(rpmalloc_thread_statistics_t *stats);
//! Get global statistics
RPMALLOC_EXPORT void
rpmalloc_global_statistics(rpmalloc_global_statistics_t *stats);
//! Dump all statistics in human readable format to file (should be a FILE*)
RPMALLOC_EXPORT void rpmalloc_dump_statistics(void *file);
//! Allocate a memory block of at least the given size
RPMALLOC_EXPORT RPMALLOC_ALLOCATOR void *
rpmalloc(size_t size) RPMALLOC_ATTRIB_MALLOC RPMALLOC_ATTRIB_ALLOC_SIZE(1);
//! Free the given memory block
RPMALLOC_EXPORT void rpfree(void *ptr);
//! Allocate a memory block of at least the given size and zero initialize it
RPMALLOC_EXPORT RPMALLOC_ALLOCATOR void *
rpcalloc(size_t num, size_t size) RPMALLOC_ATTRIB_MALLOC
RPMALLOC_ATTRIB_ALLOC_SIZE2(1, 2);
//! Reallocate the given block to at least the given size
RPMALLOC_EXPORT RPMALLOC_ALLOCATOR void *
rprealloc(void *ptr, size_t size) RPMALLOC_ATTRIB_MALLOC
RPMALLOC_ATTRIB_ALLOC_SIZE(2);
//! Reallocate the given block to at least the given size and alignment,
// with optional control flags (see RPMALLOC_NO_PRESERVE).
// Alignment must be a power of two and a multiple of sizeof(void*),
// and should ideally be less than memory page size. A caveat of rpmalloc
// internals is that this must also be strictly less than the span size
// (default 64KiB)
RPMALLOC_EXPORT RPMALLOC_ALLOCATOR void *
rpaligned_realloc(void *ptr, size_t alignment, size_t size, size_t oldsize,
unsigned int flags) RPMALLOC_ATTRIB_MALLOC
RPMALLOC_ATTRIB_ALLOC_SIZE(3);
//! Allocate a memory block of at least the given size and alignment.
// Alignment must be a power of two and a multiple of sizeof(void*),
// and should ideally be less than memory page size. A caveat of rpmalloc
// internals is that this must also be strictly less than the span size
// (default 64KiB)
RPMALLOC_EXPORT RPMALLOC_ALLOCATOR void *
rpaligned_alloc(size_t alignment, size_t size) RPMALLOC_ATTRIB_MALLOC
RPMALLOC_ATTRIB_ALLOC_SIZE(2);
//! Allocate a memory block of at least the given size and alignment, and zero
//! initialize it.
// Alignment must be a power of two and a multiple of sizeof(void*),
// and should ideally be less than memory page size. A caveat of rpmalloc
// internals is that this must also be strictly less than the span size
// (default 64KiB)
RPMALLOC_EXPORT RPMALLOC_ALLOCATOR void *
rpaligned_calloc(size_t alignment, size_t num,
size_t size) RPMALLOC_ATTRIB_MALLOC
RPMALLOC_ATTRIB_ALLOC_SIZE2(2, 3);
//! Allocate a memory block of at least the given size and alignment.
// Alignment must be a power of two and a multiple of sizeof(void*),
// and should ideally be less than memory page size. A caveat of rpmalloc
// internals is that this must also be strictly less than the span size
// (default 64KiB)
RPMALLOC_EXPORT RPMALLOC_ALLOCATOR void *
rpmemalign(size_t alignment, size_t size) RPMALLOC_ATTRIB_MALLOC
RPMALLOC_ATTRIB_ALLOC_SIZE(2);
//! Allocate a memory block of at least the given size and alignment.
// Alignment must be a power of two and a multiple of sizeof(void*),
// and should ideally be less than memory page size. A caveat of rpmalloc
// internals is that this must also be strictly less than the span size
// (default 64KiB)
RPMALLOC_EXPORT int rpposix_memalign(void **memptr, size_t alignment,
size_t size);
//! Query the usable size of the given memory block (from given pointer to the
//! end of block)
RPMALLOC_EXPORT size_t rpmalloc_usable_size(void *ptr);
//! Dummy empty function for forcing linker symbol inclusion
RPMALLOC_EXPORT void rpmalloc_linker_reference(void);
#if RPMALLOC_FIRST_CLASS_HEAPS
//! Heap type
typedef struct heap_t rpmalloc_heap_t;
//! Acquire a new heap. Will reuse existing released heaps or allocate memory
//! for a new heap
// if none available. Heap API is implemented with the strict assumption that
// only one single thread will call heap functions for a given heap at any
// given time, no functions are thread safe.
RPMALLOC_EXPORT rpmalloc_heap_t *rpmalloc_heap_acquire(void);
//! Release a heap (does NOT free the memory allocated by the heap, use
//! rpmalloc_heap_free_all before destroying the heap).
// Releasing a heap will enable it to be reused by other threads. Safe to pass
// a null pointer.
RPMALLOC_EXPORT void rpmalloc_heap_release(rpmalloc_heap_t *heap);
//! Allocate a memory block of at least the given size using the given heap.
RPMALLOC_EXPORT RPMALLOC_ALLOCATOR void *
rpmalloc_heap_alloc(rpmalloc_heap_t *heap, size_t size) RPMALLOC_ATTRIB_MALLOC
RPMALLOC_ATTRIB_ALLOC_SIZE(2);
//! Allocate a memory block of at least the given size using the given heap. The
//! returned
// block will have the requested alignment. Alignment must be a power of two
// and a multiple of sizeof(void*), and should ideally be less than memory page
// size. A caveat of rpmalloc internals is that this must also be strictly less
// than the span size (default 64KiB).
RPMALLOC_EXPORT RPMALLOC_ALLOCATOR void *
rpmalloc_heap_aligned_alloc(rpmalloc_heap_t *heap, size_t alignment,
size_t size) RPMALLOC_ATTRIB_MALLOC
RPMALLOC_ATTRIB_ALLOC_SIZE(3);
//! Allocate a memory block of at least the given size using the given heap and
//! zero initialize it.
RPMALLOC_EXPORT RPMALLOC_ALLOCATOR void *
rpmalloc_heap_calloc(rpmalloc_heap_t *heap, size_t num,
size_t size) RPMALLOC_ATTRIB_MALLOC
RPMALLOC_ATTRIB_ALLOC_SIZE2(2, 3);
//! Allocate a memory block of at least the given size using the given heap and
//! zero initialize it. The returned
// block will have the requested alignment. Alignment must either be zero, or a
// power of two and a multiple of sizeof(void*), and should ideally be less
// than memory page size. A caveat of rpmalloc internals is that this must also
// be strictly less than the span size (default 64KiB).
RPMALLOC_EXPORT RPMALLOC_ALLOCATOR void *
rpmalloc_heap_aligned_calloc(rpmalloc_heap_t *heap, size_t alignment,
size_t num, size_t size) RPMALLOC_ATTRIB_MALLOC
RPMALLOC_ATTRIB_ALLOC_SIZE2(2, 3);
//! Reallocate the given block to at least the given size. The memory block MUST
//! be allocated
// by the same heap given to this function.
RPMALLOC_EXPORT RPMALLOC_ALLOCATOR void *
rpmalloc_heap_realloc(rpmalloc_heap_t *heap, void *ptr, size_t size,
unsigned int flags) RPMALLOC_ATTRIB_MALLOC
RPMALLOC_ATTRIB_ALLOC_SIZE(3);
//! Reallocate the given block to at least the given size. The memory block MUST
//! be allocated
// by the same heap given to this function. The returned block will have the
// requested alignment. Alignment must be either zero, or a power of two and a
// multiple of sizeof(void*), and should ideally be less than memory page size.
// A caveat of rpmalloc internals is that this must also be strictly less than
// the span size (default 64KiB).
RPMALLOC_EXPORT RPMALLOC_ALLOCATOR void *rpmalloc_heap_aligned_realloc(
rpmalloc_heap_t *heap, void *ptr, size_t alignment, size_t size,
unsigned int flags) RPMALLOC_ATTRIB_MALLOC RPMALLOC_ATTRIB_ALLOC_SIZE(4);
//! Free the given memory block from the given heap. The memory block MUST be
//! allocated
// by the same heap given to this function.
RPMALLOC_EXPORT void rpmalloc_heap_free(rpmalloc_heap_t *heap, void *ptr);
//! Free all memory allocated by the heap
RPMALLOC_EXPORT void rpmalloc_heap_free_all(rpmalloc_heap_t *heap);
//! Set the given heap as the current heap for the calling thread. A heap MUST
//! only be current heap
// for a single thread, a heap can never be shared between multiple threads.
// The previous current heap for the calling thread is released to be reused by
// other threads.
RPMALLOC_EXPORT void rpmalloc_heap_thread_set_current(rpmalloc_heap_t *heap);
//! Returns which heap the given pointer is allocated on
RPMALLOC_EXPORT rpmalloc_heap_t *rpmalloc_get_heap_for_ptr(void *ptr);
#endif
#ifdef __cplusplus
}
#endif