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6830069: UseLargePages is broken on Win64

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Making VirtualAlloc/VirtualProtect two calls for PAGE_EXECUTE_READWRITE doesn't work for MEM_LARGE_PAGES.

Reviewed-by: xlu, kvn, jcoomes
This commit is contained in:
Coleen Phillimore 2009-04-21 16:12:51 -04:00
parent 425fb8197e
commit 2e43a0450f
1 changed files with 4 additions and 13 deletions
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17
hotspot/src/os/windows/vm/os_windows.cpp
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@ -2632,6 +2632,8 @@ bool os::can_execute_large_page_memory() {
char* os::reserve_memory_special(size_t bytes, char* addr, bool exec) { char* os::reserve_memory_special(size_t bytes, char* addr, bool exec) {
const DWORD prot = exec ? PAGE_EXECUTE_READWRITE : PAGE_READWRITE;
if (UseLargePagesIndividualAllocation) { if (UseLargePagesIndividualAllocation) {
if (TracePageSizes && Verbose) { if (TracePageSizes && Verbose) {
tty->print_cr("Reserving large pages individually."); tty->print_cr("Reserving large pages individually.");
@ -2694,13 +2696,7 @@ char* os::reserve_memory_special(size_t bytes, char* addr, bool exec) {
p_new = (char *) VirtualAlloc(next_alloc_addr, p_new = (char *) VirtualAlloc(next_alloc_addr,
bytes_to_rq, bytes_to_rq,
MEM_RESERVE | MEM_COMMIT | MEM_LARGE_PAGES, MEM_RESERVE | MEM_COMMIT | MEM_LARGE_PAGES,
PAGE_READWRITE); prot);
if (p_new != NULL && exec) {
DWORD oldprot;
// Windows doc says to use VirtualProtect to get execute permissions
VirtualProtect(next_alloc_addr, bytes_to_rq,
PAGE_EXECUTE_READWRITE, &oldprot);
}
} }
if (p_new == NULL) { if (p_new == NULL) {
@ -2729,12 +2725,7 @@ char* os::reserve_memory_special(size_t bytes, char* addr, bool exec) {
} else { } else {
// normal policy just allocate it all at once // normal policy just allocate it all at once
DWORD flag = MEM_RESERVE | MEM_COMMIT | MEM_LARGE_PAGES; DWORD flag = MEM_RESERVE | MEM_COMMIT | MEM_LARGE_PAGES;
char * res = (char *)VirtualAlloc(NULL, bytes, flag, PAGE_READWRITE); char * res = (char *)VirtualAlloc(NULL, bytes, flag, prot);
if (res != NULL && exec) {
DWORD oldprot;
// Windows doc says to use VirtualProtect to get execute permissions
VirtualProtect(res, bytes, PAGE_EXECUTE_READWRITE, &oldprot);
}
return res; return res;
} }
} }