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6204603: Modify hotspot to use new Solaris mmap semantics for class data archive file

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Os::attempt_reserve_memory_at() now passes an address hint to mmap

Reviewed-by: kamg, dice
This commit is contained in:
Steve Bohne 2008-03-14 10:43:02 -04:00
parent 1e62d37cc0
commit 387f42921b
2 changed files with 39 additions and 11 deletions
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49
hotspot/src/os/solaris/vm/os_solaris.cpp
View File

@ -2785,16 +2785,15 @@ char* os::Solaris::mmap_chunk(char *addr, size_t size, int flags, int prot) {
return b;
}
char*
os::reserve_memory(size_t bytes, char* requested_addr, size_t alignment_hint) {
char* addr = NULL;
int flags;
char* os::Solaris::anon_mmap(char* requested_addr, size_t bytes, size_t alignment_hint, bool fixed) {
char* addr = requested_addr;
int flags = MAP_PRIVATE | MAP_NORESERVE;
flags = MAP_PRIVATE | MAP_NORESERVE;
if (requested_addr != NULL) {
flags |= MAP_FIXED;
addr = requested_addr;
} else if (has_map_align && alignment_hint > (size_t) vm_page_size()) {
assert(!(fixed && (alignment_hint > 0)), "alignment hint meaningless with fixed mmap");
if (fixed) {
flags |= MAP_FIXED;
} else if (has_map_align && (alignment_hint > (size_t) vm_page_size())) {
flags |= MAP_ALIGN;
addr = (char*) alignment_hint;
}
@ -2802,11 +2801,14 @@ os::reserve_memory(size_t bytes, char* requested_addr, size_t alignment_hint) {
// Map uncommitted pages PROT_NONE so we fail early if we touch an
// uncommitted page. Otherwise, the read/write might succeed if we
// have enough swap space to back the physical page.
addr = Solaris::mmap_chunk(addr, bytes, flags, PROT_NONE);
return mmap_chunk(addr, bytes, flags, PROT_NONE);
}
char* os::reserve_memory(size_t bytes, char* requested_addr, size_t alignment_hint) {
char* addr = Solaris::anon_mmap(requested_addr, bytes, alignment_hint, (requested_addr != NULL));
guarantee(requested_addr == NULL || requested_addr == addr,
"OS failed to return requested mmap address.");
return addr;
}
@ -2832,6 +2834,31 @@ char* os::attempt_reserve_memory_at(size_t bytes, char* requested_addr) {
// in one of the methods further up the call chain. See bug 5044738.
assert(bytes % os::vm_page_size() == 0, "reserving unexpected size block");
// Since snv_84, Solaris attempts to honor the address hint - see 5003415.
// Give it a try, if the kernel honors the hint we can return immediately.
char* addr = Solaris::anon_mmap(requested_addr, bytes, 0, false);
volatile int err = errno;
if (addr == requested_addr) {
return addr;
} else if (addr != NULL) {
unmap_memory(addr, bytes);
}
if (PrintMiscellaneous && Verbose) {
char buf[256];
buf[0] = '\0';
if (addr == NULL) {
jio_snprintf(buf, sizeof(buf), ": %s", strerror(err));
}
warning("attempt_reserve_memory_at: couldn't reserve %d bytes at "
PTR_FORMAT ": reserve_memory_helper returned " PTR_FORMAT
"%s", bytes, requested_addr, addr, buf);
}
// Address hint method didn't work. Fall back to the old method.
// In theory, once SNV becomes our oldest supported platform, this
// code will no longer be needed.
//
// Repeatedly allocate blocks until the block is allocated at the
// right spot. Give up after max_tries.
int i;

1
hotspot/src/os/solaris/vm/os_solaris.hpp
View File

@ -156,6 +156,7 @@ class Solaris {
static int get_dev_zero_fd() { return _dev_zero_fd; }
static void set_dev_zero_fd(int fd) { _dev_zero_fd = fd; }
static char* mmap_chunk(char *addr, size_t size, int flags, int prot);
static char* anon_mmap(char* requested_addr, size_t bytes, size_t alignment_hint, bool fixed);
static bool mpss_sanity_check(bool warn, size_t * page_size);
static bool ism_sanity_check (bool warn, size_t * page_size);