qemu-e2k/include/exec/ram_addr.h
Stefan Hajnoczi 5f2cb94688 memory: make cpu_physical_memory_sync_dirty_bitmap() fully atomic
The fast path of cpu_physical_memory_sync_dirty_bitmap() directly
manipulates the dirty bitmap.  Use atomic_xchg() to make the
test-and-clear atomic.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <1417519399-3166-7-git-send-email-stefanha@redhat.com>
[Only do xchg on nonzero words. - Paolo]
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-06-05 17:10:00 +02:00

254 lines
9.1 KiB
C

/*
* Declarations for cpu physical memory functions
*
* Copyright 2011 Red Hat, Inc. and/or its affiliates
*
* Authors:
* Avi Kivity <avi@redhat.com>
*
* This work is licensed under the terms of the GNU GPL, version 2 or
* later. See the COPYING file in the top-level directory.
*
*/
/*
* This header is for use by exec.c and memory.c ONLY. Do not include it.
* The functions declared here will be removed soon.
*/
#ifndef RAM_ADDR_H
#define RAM_ADDR_H
#ifndef CONFIG_USER_ONLY
#include "hw/xen/xen.h"
ram_addr_t qemu_ram_alloc_from_file(ram_addr_t size, MemoryRegion *mr,
bool share, const char *mem_path,
Error **errp);
ram_addr_t qemu_ram_alloc_from_ptr(ram_addr_t size, void *host,
MemoryRegion *mr, Error **errp);
ram_addr_t qemu_ram_alloc(ram_addr_t size, MemoryRegion *mr, Error **errp);
ram_addr_t qemu_ram_alloc_resizeable(ram_addr_t size, ram_addr_t max_size,
void (*resized)(const char*,
uint64_t length,
void *host),
MemoryRegion *mr, Error **errp);
int qemu_get_ram_fd(ram_addr_t addr);
void *qemu_get_ram_block_host_ptr(ram_addr_t addr);
void *qemu_get_ram_ptr(ram_addr_t addr);
void qemu_ram_free(ram_addr_t addr);
void qemu_ram_free_from_ptr(ram_addr_t addr);
int qemu_ram_resize(ram_addr_t base, ram_addr_t newsize, Error **errp);
#define DIRTY_CLIENTS_ALL ((1 << DIRTY_MEMORY_NUM) - 1)
#define DIRTY_CLIENTS_NOCODE (DIRTY_CLIENTS_ALL & ~(1 << DIRTY_MEMORY_CODE))
static inline bool cpu_physical_memory_get_dirty(ram_addr_t start,
ram_addr_t length,
unsigned client)
{
unsigned long end, page, next;
assert(client < DIRTY_MEMORY_NUM);
end = TARGET_PAGE_ALIGN(start + length) >> TARGET_PAGE_BITS;
page = start >> TARGET_PAGE_BITS;
next = find_next_bit(ram_list.dirty_memory[client], end, page);
return next < end;
}
static inline bool cpu_physical_memory_all_dirty(ram_addr_t start,
ram_addr_t length,
unsigned client)
{
unsigned long end, page, next;
assert(client < DIRTY_MEMORY_NUM);
end = TARGET_PAGE_ALIGN(start + length) >> TARGET_PAGE_BITS;
page = start >> TARGET_PAGE_BITS;
next = find_next_zero_bit(ram_list.dirty_memory[client], end, page);
return next >= end;
}
static inline bool cpu_physical_memory_get_dirty_flag(ram_addr_t addr,
unsigned client)
{
return cpu_physical_memory_get_dirty(addr, 1, client);
}
static inline bool cpu_physical_memory_is_clean(ram_addr_t addr)
{
bool vga = cpu_physical_memory_get_dirty_flag(addr, DIRTY_MEMORY_VGA);
bool code = cpu_physical_memory_get_dirty_flag(addr, DIRTY_MEMORY_CODE);
bool migration =
cpu_physical_memory_get_dirty_flag(addr, DIRTY_MEMORY_MIGRATION);
return !(vga && code && migration);
}
static inline uint8_t cpu_physical_memory_range_includes_clean(ram_addr_t start,
ram_addr_t length,
uint8_t mask)
{
uint8_t ret = 0;
if (mask & (1 << DIRTY_MEMORY_VGA) &&
!cpu_physical_memory_all_dirty(start, length, DIRTY_MEMORY_VGA)) {
ret |= (1 << DIRTY_MEMORY_VGA);
}
if (mask & (1 << DIRTY_MEMORY_CODE) &&
!cpu_physical_memory_all_dirty(start, length, DIRTY_MEMORY_CODE)) {
ret |= (1 << DIRTY_MEMORY_CODE);
}
if (mask & (1 << DIRTY_MEMORY_MIGRATION) &&
!cpu_physical_memory_all_dirty(start, length, DIRTY_MEMORY_MIGRATION)) {
ret |= (1 << DIRTY_MEMORY_MIGRATION);
}
return ret;
}
static inline void cpu_physical_memory_set_dirty_flag(ram_addr_t addr,
unsigned client)
{
assert(client < DIRTY_MEMORY_NUM);
set_bit_atomic(addr >> TARGET_PAGE_BITS, ram_list.dirty_memory[client]);
}
static inline void cpu_physical_memory_set_dirty_range(ram_addr_t start,
ram_addr_t length,
uint8_t mask)
{
unsigned long end, page;
unsigned long **d = ram_list.dirty_memory;
end = TARGET_PAGE_ALIGN(start + length) >> TARGET_PAGE_BITS;
page = start >> TARGET_PAGE_BITS;
if (likely(mask & (1 << DIRTY_MEMORY_MIGRATION))) {
bitmap_set_atomic(d[DIRTY_MEMORY_MIGRATION], page, end - page);
}
if (unlikely(mask & (1 << DIRTY_MEMORY_VGA))) {
bitmap_set_atomic(d[DIRTY_MEMORY_VGA], page, end - page);
}
if (unlikely(mask & (1 << DIRTY_MEMORY_CODE))) {
bitmap_set_atomic(d[DIRTY_MEMORY_CODE], page, end - page);
}
xen_modified_memory(start, length);
}
#if !defined(_WIN32)
static inline void cpu_physical_memory_set_dirty_lebitmap(unsigned long *bitmap,
ram_addr_t start,
ram_addr_t pages)
{
unsigned long i, j;
unsigned long page_number, c;
hwaddr addr;
ram_addr_t ram_addr;
unsigned long len = (pages + HOST_LONG_BITS - 1) / HOST_LONG_BITS;
unsigned long hpratio = getpagesize() / TARGET_PAGE_SIZE;
unsigned long page = BIT_WORD(start >> TARGET_PAGE_BITS);
/* start address is aligned at the start of a word? */
if ((((page * BITS_PER_LONG) << TARGET_PAGE_BITS) == start) &&
(hpratio == 1)) {
long k;
long nr = BITS_TO_LONGS(pages);
for (k = 0; k < nr; k++) {
if (bitmap[k]) {
unsigned long temp = leul_to_cpu(bitmap[k]);
unsigned long **d = ram_list.dirty_memory;
atomic_or(&d[DIRTY_MEMORY_MIGRATION][page + k], temp);
atomic_or(&d[DIRTY_MEMORY_VGA][page + k], temp);
if (tcg_enabled()) {
atomic_or(&d[DIRTY_MEMORY_CODE][page + k], temp);
}
}
}
xen_modified_memory(start, pages << TARGET_PAGE_BITS);
} else {
uint8_t clients = tcg_enabled() ? DIRTY_CLIENTS_ALL : DIRTY_CLIENTS_NOCODE;
/*
* bitmap-traveling is faster than memory-traveling (for addr...)
* especially when most of the memory is not dirty.
*/
for (i = 0; i < len; i++) {
if (bitmap[i] != 0) {
c = leul_to_cpu(bitmap[i]);
do {
j = ctzl(c);
c &= ~(1ul << j);
page_number = (i * HOST_LONG_BITS + j) * hpratio;
addr = page_number * TARGET_PAGE_SIZE;
ram_addr = start + addr;
cpu_physical_memory_set_dirty_range(ram_addr,
TARGET_PAGE_SIZE * hpratio, clients);
} while (c != 0);
}
}
}
}
#endif /* not _WIN32 */
bool cpu_physical_memory_test_and_clear_dirty(ram_addr_t start,
ram_addr_t length,
unsigned client);
static inline void cpu_physical_memory_clear_dirty_range(ram_addr_t start,
ram_addr_t length)
{
cpu_physical_memory_test_and_clear_dirty(start, length, DIRTY_MEMORY_MIGRATION);
cpu_physical_memory_test_and_clear_dirty(start, length, DIRTY_MEMORY_VGA);
cpu_physical_memory_test_and_clear_dirty(start, length, DIRTY_MEMORY_CODE);
}
static inline
uint64_t cpu_physical_memory_sync_dirty_bitmap(unsigned long *dest,
ram_addr_t start,
ram_addr_t length)
{
ram_addr_t addr;
unsigned long page = BIT_WORD(start >> TARGET_PAGE_BITS);
uint64_t num_dirty = 0;
/* start address is aligned at the start of a word? */
if (((page * BITS_PER_LONG) << TARGET_PAGE_BITS) == start) {
int k;
int nr = BITS_TO_LONGS(length >> TARGET_PAGE_BITS);
unsigned long *src = ram_list.dirty_memory[DIRTY_MEMORY_MIGRATION];
for (k = page; k < page + nr; k++) {
if (src[k]) {
unsigned long bits = atomic_xchg(&src[k], 0);
unsigned long new_dirty;
new_dirty = ~dest[k];
dest[k] |= bits;
new_dirty &= bits;
num_dirty += ctpopl(new_dirty);
}
}
} else {
for (addr = 0; addr < length; addr += TARGET_PAGE_SIZE) {
if (cpu_physical_memory_test_and_clear_dirty(
start + addr,
TARGET_PAGE_SIZE,
DIRTY_MEMORY_MIGRATION)) {
long k = (start + addr) >> TARGET_PAGE_BITS;
if (!test_and_set_bit(k, dest)) {
num_dirty++;
}
}
}
}
return num_dirty;
}
#endif
#endif