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Use standard _Atomic declarations and clean up atomic operations

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This commit is contained in:
daan 2019-08-25 22:59:12 -07:00
parent b86c851cca
commit e8664001f7
9 changed files with 165 additions and 159 deletions
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18
src/os.c
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@ -186,11 +186,11 @@ static bool mi_os_mem_free(void* addr, size_t size, mi_stats_t* stats)
static void* mi_win_virtual_allocx(void* addr, size_t size, size_t try_alignment, DWORD flags) {
#if (MI_INTPTR_SIZE >= 8)
// on 64-bit systems, use the virtual address area after 4TiB for 4MiB aligned allocations
static volatile intptr_t aligned_base = ((intptr_t)4 << 40); // starting at 4TiB
static volatile _Atomic(intptr_t) aligned_base = ATOMIC_VAR_INIT((intptr_t)4 << 40); // starting at 4TiB
if (addr == NULL && try_alignment > 0 &&
try_alignment <= MI_SEGMENT_SIZE && (size%MI_SEGMENT_SIZE) == 0)
{
intptr_t hint = mi_atomic_add(&aligned_base, size) - size;
intptr_t hint = mi_atomic_add(&aligned_base, size);
if (hint%try_alignment == 0) {
return VirtualAlloc((void*)hint, size, flags, PAGE_READWRITE);
}
@ -214,11 +214,11 @@ static void* mi_win_virtual_alloc(void* addr, size_t size, size_t try_alignment,
static volatile uintptr_t large_page_try_ok = 0;
void* p = NULL;
if (use_large_os_page(size, try_alignment)) {
uintptr_t try_ok = mi_atomic_read(&large_page_try_ok);
uintptr_t try_ok = mi_atomic_read_relaxed(&large_page_try_ok);
if (try_ok > 0) {
// if a large page allocation fails, it seems the calls to VirtualAlloc get very expensive.
// therefore, once a large page allocation failed, we don't try again for `large_page_try_ok` times.
mi_atomic_compare_exchange(&large_page_try_ok, try_ok - 1, try_ok);
mi_atomic_cas_weak(&large_page_try_ok, try_ok - 1, try_ok);
}
else {
// large OS pages must always reserve and commit.
@ -253,9 +253,9 @@ static void* mi_unix_mmapx(size_t size, size_t try_alignment, int protect_flags,
void* p = NULL;
#if (MI_INTPTR_SIZE >= 8) && !defined(MAP_ALIGNED)
// on 64-bit systems, use the virtual address area after 4TiB for 4MiB aligned allocations
static volatile intptr_t aligned_base = ((intptr_t)1 << 42); // starting at 4TiB
static volatile _Atomic(intptr_t) aligned_base = ATOMIC_VAR_INIT((intptr_t)1 << 42); // starting at 4TiB
if (try_alignment <= MI_SEGMENT_SIZE && (size%MI_SEGMENT_SIZE)==0) {
intptr_t hint = mi_atomic_add(&aligned_base,size) - size;
intptr_t hint = mi_atomic_add(&aligned_base,size);
if (hint%try_alignment == 0) {
p = mmap((void*)hint,size,protect_flags,flags,fd,0);
if (p==MAP_FAILED) p = NULL; // fall back to regular mmap
@ -291,14 +291,14 @@ static void* mi_unix_mmap(size_t size, size_t try_alignment, int protect_flags)
fd = VM_MAKE_TAG(100);
#endif
if (use_large_os_page(size, try_alignment)) {
static volatile uintptr_t large_page_try_ok = 0;
uintptr_t try_ok = mi_atomic_read(&large_page_try_ok);
static volatile _Atomic(uintptr_t) large_page_try_ok = 0;
uintptr_t try_ok = mi_atomic_read_relaxed(&large_page_try_ok);
if (try_ok > 0) {
// If the OS is not configured for large OS pages, or the user does not have
// enough permission, the `mmap` will always fail (but it might also fail for other reasons).
// Therefore, once a large page allocation failed, we don't try again for `large_page_try_ok` times
// to avoid too many failing calls to mmap.
mi_atomic_compare_exchange(&large_page_try_ok, try_ok - 1, try_ok);
mi_atomic_cas_weak(&large_page_try_ok, try_ok - 1, try_ok);
}
else {
int lflags = flags;