kiper220/mimalloc
1
0
Fork 0
mirror of https://github.com/microsoft/mimalloc.git synced 2025-07-06 19:38:41 +03:00
Code Issues Projects Releases Packages Wiki Activity Actions

move threadid and mi_get_default_heap to primitives

Browse source
This commit is contained in:
Daan Leijen 2023-03-14 20:35:00 -07:00
parent 3579d3b861
commit 9b110090b2
9 changed files with 152 additions and 137 deletions
Download patch file Download diff file Expand all files Collapse all files

94
include/mimalloc-internal.h
View file

@ -73,8 +73,9 @@ extern mi_decl_cache_align mi_stats_t _mi_stats_main;
extern mi_decl_cache_align const mi_page_t _mi_page_empty;
bool _mi_is_main_thread(void);
size_t _mi_current_thread_count(void);
bool _mi_preloading(void); // true while the C runtime is not ready
bool _mi_preloading(void); // true while the C runtime is not ready
mi_threadid_t _mi_thread_id(void) mi_attr_noexcept;
mi_heap_t* _mi_heap_main_get(void); // statically allocated main backing heap
// os.c
size_t _mi_os_page_size(void);
@ -329,93 +330,11 @@ static inline bool mi_count_size_overflow(size_t count, size_t size, size_t* tot
}
/* ----------------------------------------------------------------------------------------
The thread local default heap: `_mi_get_default_heap` returns the thread local heap.
On most platforms (Windows, Linux, FreeBSD, NetBSD, etc), this just returns a
__thread local variable (`_mi_heap_default`). With the initial-exec TLS model this ensures
that the storage will always be available (allocated on the thread stacks).
On some platforms though we cannot use that when overriding `malloc` since the underlying
TLS implementation (or the loader) will call itself `malloc` on a first access and recurse.
We try to circumvent this in an efficient way:
- macOSX : we use an unused TLS slot from the OS allocated slots (MI_TLS_SLOT). On OSX, the
loader itself calls `malloc` even before the modules are initialized.
- OpenBSD: we use an unused slot from the pthread block (MI_TLS_PTHREAD_SLOT_OFS).
- DragonFly: defaults are working but seem slow compared to freeBSD (see PR #323)
/*----------------------------------------------------------------------------------------
Heap functions
------------------------------------------------------------------------------------------- */
extern const mi_heap_t _mi_heap_empty; // read-only empty heap, initial value of the thread local default heap
extern bool _mi_process_is_initialized;
mi_heap_t* _mi_heap_main_get(void); // statically allocated main backing heap
#if defined(MI_MALLOC_OVERRIDE)
#if defined(__APPLE__) // macOS
#define MI_TLS_SLOT 89 // seems unused?
// #define MI_TLS_RECURSE_GUARD 1
// other possible unused ones are 9, 29, __PTK_FRAMEWORK_JAVASCRIPTCORE_KEY4 (94), __PTK_FRAMEWORK_GC_KEY9 (112) and __PTK_FRAMEWORK_OLDGC_KEY9 (89)
// see <https://github.com/rweichler/substrate/blob/master/include/pthread_machdep.h>
#elif defined(__OpenBSD__)
// use end bytes of a name; goes wrong if anyone uses names > 23 characters (ptrhread specifies 16)
// see <https://github.com/openbsd/src/blob/master/lib/libc/include/thread_private.h#L371>
#define MI_TLS_PTHREAD_SLOT_OFS (6*sizeof(int) + 4*sizeof(void*) + 24)
// #elif defined(__DragonFly__)
// #warning "mimalloc is not working correctly on DragonFly yet."
// #define MI_TLS_PTHREAD_SLOT_OFS (4 + 1*sizeof(void*)) // offset `uniqueid` (also used by gdb?) <https://github.com/DragonFlyBSD/DragonFlyBSD/blob/master/lib/libthread_xu/thread/thr_private.h#L458>
#elif defined(__ANDROID__)
// See issue #381
#define MI_TLS_PTHREAD
#endif
#endif
#if defined(MI_TLS_SLOT)
static inline void* mi_tls_slot(size_t slot) mi_attr_noexcept; // forward declaration
#elif defined(MI_TLS_PTHREAD_SLOT_OFS)
static inline mi_heap_t** mi_tls_pthread_heap_slot(void) {
pthread_t self = pthread_self();
#if defined(__DragonFly__)
if (self==NULL) {
mi_heap_t* pheap_main = _mi_heap_main_get();
return &pheap_main;
}
#endif
return (mi_heap_t**)((uint8_t*)self + MI_TLS_PTHREAD_SLOT_OFS);
}
#elif defined(MI_TLS_PTHREAD)
extern pthread_key_t _mi_heap_default_key;
#endif
// Default heap to allocate from (if not using TLS- or pthread slots).
// Do not use this directly but use through `mi_heap_get_default()` (or the unchecked `mi_get_default_heap`).
// This thread local variable is only used when neither MI_TLS_SLOT, MI_TLS_PTHREAD, or MI_TLS_PTHREAD_SLOT_OFS are defined.
// However, on the Apple M1 we do use the address of this variable as the unique thread-id (issue #356).
extern mi_decl_thread mi_heap_t* _mi_heap_default; // default heap to allocate from
static inline mi_heap_t* mi_get_default_heap(void) {
#if defined(MI_TLS_SLOT)
mi_heap_t* heap = (mi_heap_t*)mi_tls_slot(MI_TLS_SLOT);
if mi_unlikely(heap == NULL) {
#ifdef __GNUC__
__asm(""); // prevent conditional load of the address of _mi_heap_empty
#endif
heap = (mi_heap_t*)&_mi_heap_empty;
}
return heap;
#elif defined(MI_TLS_PTHREAD_SLOT_OFS)
mi_heap_t* heap = *mi_tls_pthread_heap_slot();
return (mi_unlikely(heap == NULL) ? (mi_heap_t*)&_mi_heap_empty : heap);
#elif defined(MI_TLS_PTHREAD)
mi_heap_t* heap = (mi_unlikely(_mi_heap_default_key == (pthread_key_t)(-1)) ? _mi_heap_main_get() : (mi_heap_t*)pthread_getspecific(_mi_heap_default_key));
return (mi_unlikely(heap == NULL) ? (mi_heap_t*)&_mi_heap_empty : heap);
#else
#if defined(MI_TLS_RECURSE_GUARD)
if (mi_unlikely(!_mi_process_is_initialized)) return _mi_heap_main_get();
#endif
return _mi_heap_default;
#endif
}
static inline bool mi_heap_is_default(const mi_heap_t* heap) {
return (heap == mi_get_default_heap());
}
static inline bool mi_heap_is_backing(const mi_heap_t* heap) {
return (heap->tld->heap_backing == heap);
@ -443,11 +362,6 @@ static inline mi_page_t* _mi_heap_get_free_small_page(mi_heap_t* heap, size_t si
return heap->pages_free_direct[idx];
}
// Get the page belonging to a certain size class
static inline mi_page_t* _mi_get_free_small_page(size_t size) {
return _mi_heap_get_free_small_page(mi_get_default_heap(), size);
}
// Segment that contains the pointer
// Large aligned blocks may be aligned at N*MI_SEGMENT_SIZE (inside a huge segment > MI_SEGMENT_SIZE),
// and we need align "down" to the segment info which is `MI_SEGMENT_SIZE` bytes before it;