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improve aligned support on BSD and MAP_ALIGN systems

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This commit is contained in:
Daan 2021-11-10 11:23:11 -08:00
parent 8c9ccea2f5
commit 89abbe75d8
1 changed files with 34 additions and 22 deletions
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56
src/os.c
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@ -413,23 +413,41 @@ static void* mi_wasm_heap_grow(size_t size, size_t try_alignment) {
#else
#define MI_OS_USE_MMAP
static void* mi_unix_mmapx(void* addr, size_t size, size_t try_alignment, int protect_flags, int flags, int fd) {
UNUSED(try_alignment);
void* p = NULL;
#if defined(MAP_ALIGNED) // BSD
if (addr == NULL && try_alignment > 0 && (try_alignment % _mi_os_page_size()) == 0) {
size_t n = mi_bsr(try_alignment);
if (((size_t)1 << n) == try_alignment && n >= 12 && n <= 30) { // alignment is a power of 2 and 4096 <= alignment <= 1GiB
flags |= MAP_ALIGNED(n);
p = mmap(addr, size, protect_flags, flags | MAP_ALIGNED(n), fd, 0);
if (p!=MAP_FAILED) return p;
// fall back to regular mmap
}
}
#elif defined(MAP_ALIGN) // Solaris
if (addr == NULL && try_alignment > 0 && (try_alignment % _mi_os_page_size()) == 0) {
p = mmap(try_alignment, size, protect_flags, flags | MAP_ALIGN, fd, 0);
if (p!=MAP_FAILED) return p;
// fall back to regular mmap
}
#endif
#if (MI_INTPTR_SIZE >= 8) && !defined(MAP_ALIGNED)
// on 64-bit systems, use the virtual address area after 2TiB for 4MiB aligned allocations
void* hint;
if (addr == NULL && (hint = mi_os_get_aligned_hint(try_alignment, size)) != NULL) {
p = mmap(hint,size,protect_flags,flags,fd,0);
if (p==MAP_FAILED) p = NULL; // fall back to regular mmap
if (addr == NULL) {
void* hint = mi_os_get_aligned_hint(try_alignment, size);
if (hint != NULL) {
p = mmap(hint, size, protect_flags, flags, fd, 0);
if (p!=MAP_FAILED) return p;
// fall back to regular mmap
}
}
#else
UNUSED(try_alignment);
UNUSED(mi_os_get_aligned_hint);
#endif
if (p==NULL) {
p = mmap(addr,size,protect_flags,flags,fd,0);
if (p==MAP_FAILED) p = NULL;
}
return p;
// regular mmap
p = mmap(addr, size, protect_flags, flags, fd, 0);
if (p!=MAP_FAILED) return p;
// failed to allocate
return NULL;
}
static void* mi_unix_mmap(void* addr, size_t size, size_t try_alignment, int protect_flags, bool large_only, bool allow_large, bool* is_large) {
@ -444,24 +462,17 @@ static void* mi_unix_mmap(void* addr, size_t size, size_t try_alignment, int pro
int fd = -1;
if (os_overcommit) {
flags |= MAP_NORESERVE;
}
#if defined(MAP_ALIGNED) // BSD
if (try_alignment > 0) {
size_t n = mi_bsr(try_alignment);
if (((size_t)1 << n) == try_alignment && n >= 12 && n <= 30) { // alignment is a power of 2 and 4096 <= alignment <= 1GiB
flags |= MAP_ALIGNED(n);
}
}
#endif
}
#if defined(PROT_MAX)
protect_flags |= PROT_MAX(PROT_READ | PROT_WRITE); // BSD
#endif
#if defined(VM_MAKE_TAG)
// macOS: tracking anonymous page with a specific ID. (All up to 98 are taken officially but LLVM sanitizers had taken 99)
int os_tag = (int)mi_option_get(mi_option_os_tag);
if (os_tag < 100 || os_tag > 255) os_tag = 100;
if (os_tag < 100 || os_tag > 255) { os_tag = 100; }
fd = VM_MAKE_TAG(os_tag);
#endif
// huge page allocation
if ((large_only || use_large_os_page(size, try_alignment)) && allow_large) {
static _Atomic(uintptr_t) large_page_try_ok; // = 0;
uintptr_t try_ok = mi_atomic_load_acquire(&large_page_try_ok);
@ -515,6 +526,7 @@ static void* mi_unix_mmap(void* addr, size_t size, size_t try_alignment, int pro
}
}
}
// regular allocation
if (p == NULL) {
*is_large = false;
p = mi_unix_mmapx(addr, size, try_alignment, protect_flags, flags, fd);