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Diffstat (limited to 'qemu/include/exec/ram_addr.h')
-rw-r--r--qemu/include/exec/ram_addr.h276
1 files changed, 240 insertions, 36 deletions
diff --git a/qemu/include/exec/ram_addr.h b/qemu/include/exec/ram_addr.h
index c113f2114..5adf7a4fc 100644
--- a/qemu/include/exec/ram_addr.h
+++ b/qemu/include/exec/ram_addr.h
@@ -22,22 +22,93 @@
#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);
+struct RAMBlock {
+ struct rcu_head rcu;
+ struct MemoryRegion *mr;
+ uint8_t *host;
+ ram_addr_t offset;
+ ram_addr_t used_length;
+ ram_addr_t max_length;
+ void (*resized)(const char*, uint64_t length, void *host);
+ uint32_t flags;
+ /* Protected by iothread lock. */
+ char idstr[256];
+ /* RCU-enabled, writes protected by the ramlist lock */
+ QLIST_ENTRY(RAMBlock) next;
+ int fd;
+};
+
+static inline bool offset_in_ramblock(RAMBlock *b, ram_addr_t offset)
+{
+ return (b && b->host && offset < b->used_length) ? true : false;
+}
+
+static inline void *ramblock_ptr(RAMBlock *block, ram_addr_t offset)
+{
+ assert(offset_in_ramblock(block, offset));
+ return (char *)block->host + offset;
+}
+
+/* The dirty memory bitmap is split into fixed-size blocks to allow growth
+ * under RCU. The bitmap for a block can be accessed as follows:
+ *
+ * rcu_read_lock();
+ *
+ * DirtyMemoryBlocks *blocks =
+ * atomic_rcu_read(&ram_list.dirty_memory[DIRTY_MEMORY_MIGRATION]);
+ *
+ * ram_addr_t idx = (addr >> TARGET_PAGE_BITS) / DIRTY_MEMORY_BLOCK_SIZE;
+ * unsigned long *block = blocks.blocks[idx];
+ * ...access block bitmap...
+ *
+ * rcu_read_unlock();
+ *
+ * Remember to check for the end of the block when accessing a range of
+ * addresses. Move on to the next block if you reach the end.
+ *
+ * Organization into blocks allows dirty memory to grow (but not shrink) under
+ * RCU. When adding new RAMBlocks requires the dirty memory to grow, a new
+ * DirtyMemoryBlocks array is allocated with pointers to existing blocks kept
+ * the same. Other threads can safely access existing blocks while dirty
+ * memory is being grown. When no threads are using the old DirtyMemoryBlocks
+ * anymore it is freed by RCU (but the underlying blocks stay because they are
+ * pointed to from the new DirtyMemoryBlocks).
+ */
+#define DIRTY_MEMORY_BLOCK_SIZE ((ram_addr_t)256 * 1024 * 8)
+typedef struct {
+ struct rcu_head rcu;
+ unsigned long *blocks[];
+} DirtyMemoryBlocks;
+
+typedef struct RAMList {
+ QemuMutex mutex;
+ RAMBlock *mru_block;
+ /* RCU-enabled, writes protected by the ramlist lock. */
+ QLIST_HEAD(, RAMBlock) blocks;
+ DirtyMemoryBlocks *dirty_memory[DIRTY_MEMORY_NUM];
+ uint32_t version;
+} RAMList;
+extern RAMList ram_list;
+
+ram_addr_t last_ram_offset(void);
+void qemu_mutex_lock_ramlist(void);
+void qemu_mutex_unlock_ramlist(void);
+
+RAMBlock *qemu_ram_alloc_from_file(ram_addr_t size, MemoryRegion *mr,
+ bool share, const char *mem_path,
+ Error **errp);
+RAMBlock *qemu_ram_alloc_from_ptr(ram_addr_t size, void *host,
+ MemoryRegion *mr, Error **errp);
+RAMBlock *qemu_ram_alloc(ram_addr_t size, MemoryRegion *mr, Error **errp);
+RAMBlock *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_set_ram_fd(ram_addr_t addr, int fd);
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);
+void qemu_ram_free(RAMBlock *block);
int qemu_ram_resize(ram_addr_t base, ram_addr_t newsize, Error **errp);
@@ -48,30 +119,82 @@ static inline bool cpu_physical_memory_get_dirty(ram_addr_t start,
ram_addr_t length,
unsigned client)
{
- unsigned long end, page, next;
+ DirtyMemoryBlocks *blocks;
+ unsigned long end, page;
+ unsigned long idx, offset, base;
+ bool dirty = false;
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;
+ rcu_read_lock();
+
+ blocks = atomic_rcu_read(&ram_list.dirty_memory[client]);
+
+ idx = page / DIRTY_MEMORY_BLOCK_SIZE;
+ offset = page % DIRTY_MEMORY_BLOCK_SIZE;
+ base = page - offset;
+ while (page < end) {
+ unsigned long next = MIN(end, base + DIRTY_MEMORY_BLOCK_SIZE);
+ unsigned long num = next - base;
+ unsigned long found = find_next_bit(blocks->blocks[idx], num, offset);
+ if (found < num) {
+ dirty = true;
+ break;
+ }
+
+ page = next;
+ idx++;
+ offset = 0;
+ base += DIRTY_MEMORY_BLOCK_SIZE;
+ }
+
+ rcu_read_unlock();
+
+ return dirty;
}
static inline bool cpu_physical_memory_all_dirty(ram_addr_t start,
ram_addr_t length,
unsigned client)
{
- unsigned long end, page, next;
+ DirtyMemoryBlocks *blocks;
+ unsigned long end, page;
+ unsigned long idx, offset, base;
+ bool dirty = true;
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;
+ rcu_read_lock();
+
+ blocks = atomic_rcu_read(&ram_list.dirty_memory[client]);
+
+ idx = page / DIRTY_MEMORY_BLOCK_SIZE;
+ offset = page % DIRTY_MEMORY_BLOCK_SIZE;
+ base = page - offset;
+ while (page < end) {
+ unsigned long next = MIN(end, base + DIRTY_MEMORY_BLOCK_SIZE);
+ unsigned long num = next - base;
+ unsigned long found = find_next_zero_bit(blocks->blocks[idx], num, offset);
+ if (found < num) {
+ dirty = false;
+ break;
+ }
+
+ page = next;
+ idx++;
+ offset = 0;
+ base += DIRTY_MEMORY_BLOCK_SIZE;
+ }
+
+ rcu_read_unlock();
+
+ return dirty;
}
static inline bool cpu_physical_memory_get_dirty_flag(ram_addr_t addr,
@@ -113,28 +236,73 @@ static inline uint8_t cpu_physical_memory_range_includes_clean(ram_addr_t start,
static inline void cpu_physical_memory_set_dirty_flag(ram_addr_t addr,
unsigned client)
{
+ unsigned long page, idx, offset;
+ DirtyMemoryBlocks *blocks;
+
assert(client < DIRTY_MEMORY_NUM);
- set_bit_atomic(addr >> TARGET_PAGE_BITS, ram_list.dirty_memory[client]);
+
+ page = addr >> TARGET_PAGE_BITS;
+ idx = page / DIRTY_MEMORY_BLOCK_SIZE;
+ offset = page % DIRTY_MEMORY_BLOCK_SIZE;
+
+ rcu_read_lock();
+
+ blocks = atomic_rcu_read(&ram_list.dirty_memory[client]);
+
+ set_bit_atomic(offset, blocks->blocks[idx]);
+
+ rcu_read_unlock();
}
static inline void cpu_physical_memory_set_dirty_range(ram_addr_t start,
ram_addr_t length,
uint8_t mask)
{
+ DirtyMemoryBlocks *blocks[DIRTY_MEMORY_NUM];
unsigned long end, page;
- unsigned long **d = ram_list.dirty_memory;
+ unsigned long idx, offset, base;
+ int i;
+
+ if (!mask && !xen_enabled()) {
+ return;
+ }
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);
+
+ rcu_read_lock();
+
+ for (i = 0; i < DIRTY_MEMORY_NUM; i++) {
+ blocks[i] = atomic_rcu_read(&ram_list.dirty_memory[i]);
}
- if (unlikely(mask & (1 << DIRTY_MEMORY_CODE))) {
- bitmap_set_atomic(d[DIRTY_MEMORY_CODE], page, end - page);
+
+ idx = page / DIRTY_MEMORY_BLOCK_SIZE;
+ offset = page % DIRTY_MEMORY_BLOCK_SIZE;
+ base = page - offset;
+ while (page < end) {
+ unsigned long next = MIN(end, base + DIRTY_MEMORY_BLOCK_SIZE);
+
+ if (likely(mask & (1 << DIRTY_MEMORY_MIGRATION))) {
+ bitmap_set_atomic(blocks[DIRTY_MEMORY_MIGRATION]->blocks[idx],
+ offset, next - page);
+ }
+ if (unlikely(mask & (1 << DIRTY_MEMORY_VGA))) {
+ bitmap_set_atomic(blocks[DIRTY_MEMORY_VGA]->blocks[idx],
+ offset, next - page);
+ }
+ if (unlikely(mask & (1 << DIRTY_MEMORY_CODE))) {
+ bitmap_set_atomic(blocks[DIRTY_MEMORY_CODE]->blocks[idx],
+ offset, next - page);
+ }
+
+ page = next;
+ idx++;
+ offset = 0;
+ base += DIRTY_MEMORY_BLOCK_SIZE;
}
+
+ rcu_read_unlock();
+
xen_modified_memory(start, length);
}
@@ -154,21 +322,41 @@ static inline void cpu_physical_memory_set_dirty_lebitmap(unsigned long *bitmap,
/* start address is aligned at the start of a word? */
if ((((page * BITS_PER_LONG) << TARGET_PAGE_BITS) == start) &&
(hpratio == 1)) {
+ unsigned long **blocks[DIRTY_MEMORY_NUM];
+ unsigned long idx;
+ unsigned long offset;
long k;
long nr = BITS_TO_LONGS(pages);
+ idx = (start >> TARGET_PAGE_BITS) / DIRTY_MEMORY_BLOCK_SIZE;
+ offset = BIT_WORD((start >> TARGET_PAGE_BITS) %
+ DIRTY_MEMORY_BLOCK_SIZE);
+
+ rcu_read_lock();
+
+ for (i = 0; i < DIRTY_MEMORY_NUM; i++) {
+ blocks[i] = atomic_rcu_read(&ram_list.dirty_memory[i])->blocks;
+ }
+
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);
+ atomic_or(&blocks[DIRTY_MEMORY_MIGRATION][idx][offset], temp);
+ atomic_or(&blocks[DIRTY_MEMORY_VGA][idx][offset], temp);
if (tcg_enabled()) {
- atomic_or(&d[DIRTY_MEMORY_CODE][page + k], temp);
+ atomic_or(&blocks[DIRTY_MEMORY_CODE][idx][offset], temp);
}
}
+
+ if (++offset >= BITS_TO_LONGS(DIRTY_MEMORY_BLOCK_SIZE)) {
+ offset = 0;
+ idx++;
+ }
}
+
+ rcu_read_unlock();
+
xen_modified_memory(start, pages << TARGET_PAGE_BITS);
} else {
uint8_t clients = tcg_enabled() ? DIRTY_CLIENTS_ALL : DIRTY_CLIENTS_NOCODE;
@@ -220,18 +408,33 @@ uint64_t cpu_physical_memory_sync_dirty_bitmap(unsigned long *dest,
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];
+ unsigned long * const *src;
+ unsigned long idx = (page * BITS_PER_LONG) / DIRTY_MEMORY_BLOCK_SIZE;
+ unsigned long offset = BIT_WORD((page * BITS_PER_LONG) %
+ DIRTY_MEMORY_BLOCK_SIZE);
+
+ rcu_read_lock();
+
+ src = atomic_rcu_read(
+ &ram_list.dirty_memory[DIRTY_MEMORY_MIGRATION])->blocks;
for (k = page; k < page + nr; k++) {
- if (src[k]) {
- unsigned long bits = atomic_xchg(&src[k], 0);
+ if (src[idx][offset]) {
+ unsigned long bits = atomic_xchg(&src[idx][offset], 0);
unsigned long new_dirty;
new_dirty = ~dest[k];
dest[k] |= bits;
new_dirty &= bits;
num_dirty += ctpopl(new_dirty);
}
+
+ if (++offset >= BITS_TO_LONGS(DIRTY_MEMORY_BLOCK_SIZE)) {
+ offset = 0;
+ idx++;
+ }
}
+
+ rcu_read_unlock();
} else {
for (addr = 0; addr < length; addr += TARGET_PAGE_SIZE) {
if (cpu_physical_memory_test_and_clear_dirty(
@@ -249,5 +452,6 @@ uint64_t cpu_physical_memory_sync_dirty_bitmap(unsigned long *dest,
return num_dirty;
}
+void migration_bitmap_extend(ram_addr_t old, ram_addr_t new);
#endif
#endif