3party/mimalloc
0
0
Fork 0
mirror of https://github.com/microsoft/mimalloc.git synced 2024-12-28 13:58:30 +08:00
Code Issues Projects Releases Wiki Activity

Merge branch 'dev' into dev-win

Browse Source
This commit is contained in:
daan 2019-07-15 10:04:55 -07:00
commit 76a5adfbfe
1 changed files with 15 additions and 3 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

18
src/os.c
View File

@ -180,7 +180,7 @@ 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 defined(MEM_EXTENDED_PARAMETER_TYPE_BITS)
if (try_alignment > 0 && (try_alignment % _mi_os_page_size()) == 0 && pVirtualAlloc2 != NULL) {
// on modern Windows try use VirtualAlloc2
// on modern Windows try use VirtualAlloc2 for aligned allocation
MEM_ADDRESS_REQUIREMENTS reqs = { 0 };
reqs.Alignment = try_alignment;
MEM_EXTENDED_PARAMETER param = { 0 };
@ -193,10 +193,22 @@ static void* mi_win_virtual_allocx(void* addr, size_t size, size_t try_alignment
}
static void* mi_win_virtual_alloc(void* addr, size_t size, size_t try_alignment, DWORD flags) {
static size_t large_page_try_ok = 0;
void* p = NULL;
if (use_large_os_page(size, try_alignment)) {
p = mi_win_virtual_allocx(addr, size, try_alignment, MEM_LARGE_PAGES | flags);
// fall back to non-large page allocation on error (`p == NULL`).
if (large_page_try_ok > 0) {
// if a large page 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.
large_page_try_ok--;
}
else {
// large OS pages must always reserve and commit.
p = mi_win_virtual_allocx(addr, size, try_alignment, MEM_LARGE_PAGES | MEM_COMMIT | MEM_RESERVE | flags);
// fall back to non-large page allocation on error (`p == NULL`).
if (p == NULL) {
large_page_try_ok = 10; // on error, don't try again for the next N allocations
}
}
}
if (p == NULL) {
p = mi_win_virtual_allocx(addr, size, try_alignment, flags);