memory: make global_dirty_tracking a bitmask
since dirty ring has been introduced, there are two methods
to track dirty pages of vm. it seems that "logging" has
a hint on the method, so rename the global_dirty_log to
global_dirty_tracking would make description more accurate.
dirty rate measurement may start or stop dirty tracking during
calculation. this conflict with migration because stop dirty
tracking make migration leave dirty pages out then that'll be
a problem.
make global_dirty_tracking a bitmask can let both migration and
dirty rate measurement work fine. introduce GLOBAL_DIRTY_MIGRATION
and GLOBAL_DIRTY_DIRTY_RATE to distinguish what current dirty
tracking aims for, migration or dirty rate.
Signed-off-by: Hyman Huang(黄勇) <huangy81@chinatelecom.cn>
Message-Id: <9c9388657cfa0301bd2c1cfa36e7cf6da4aeca19.1624040308.git.huangy81@chinatelecom.cn>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
diff --git a/hw/i386/xen/xen-hvm.c b/hw/i386/xen/xen-hvm.c
index e3d3d5c..482be95 100644
--- a/hw/i386/xen/xen-hvm.c
+++ b/hw/i386/xen/xen-hvm.c
@@ -1613,8 +1613,8 @@
void qmp_xen_set_global_dirty_log(bool enable, Error **errp)
{
if (enable) {
- memory_global_dirty_log_start();
+ memory_global_dirty_log_start(GLOBAL_DIRTY_MIGRATION);
} else {
- memory_global_dirty_log_stop();
+ memory_global_dirty_log_stop(GLOBAL_DIRTY_MIGRATION);
}
}
diff --git a/include/exec/memory.h b/include/exec/memory.h
index a185b6d..0428045 100644
--- a/include/exec/memory.h
+++ b/include/exec/memory.h
@@ -61,7 +61,17 @@
}
#endif
-extern bool global_dirty_log;
+/* Possible bits for global_dirty_log_{start|stop} */
+
+/* Dirty tracking enabled because migration is running */
+#define GLOBAL_DIRTY_MIGRATION (1U << 0)
+
+/* Dirty tracking enabled because measuring dirty rate */
+#define GLOBAL_DIRTY_DIRTY_RATE (1U << 1)
+
+#define GLOBAL_DIRTY_MASK (0x3)
+
+extern unsigned int global_dirty_tracking;
typedef struct MemoryRegionOps MemoryRegionOps;
@@ -2388,13 +2398,17 @@
/**
* memory_global_dirty_log_start: begin dirty logging for all regions
+ *
+ * @flags: purpose of starting dirty log, migration or dirty rate
*/
-void memory_global_dirty_log_start(void);
+void memory_global_dirty_log_start(unsigned int flags);
/**
* memory_global_dirty_log_stop: end dirty logging for all regions
+ *
+ * @flags: purpose of stopping dirty log, migration or dirty rate
*/
-void memory_global_dirty_log_stop(void);
+void memory_global_dirty_log_stop(unsigned int flags);
void mtree_info(bool flatview, bool dispatch_tree, bool owner, bool disabled);
diff --git a/include/exec/ram_addr.h b/include/exec/ram_addr.h
index 551876b..45c9132 100644
--- a/include/exec/ram_addr.h
+++ b/include/exec/ram_addr.h
@@ -369,7 +369,7 @@
qatomic_or(&blocks[DIRTY_MEMORY_VGA][idx][offset], temp);
- if (global_dirty_log) {
+ if (global_dirty_tracking) {
qatomic_or(
&blocks[DIRTY_MEMORY_MIGRATION][idx][offset],
temp);
@@ -392,7 +392,7 @@
} else {
uint8_t clients = tcg_enabled() ? DIRTY_CLIENTS_ALL : DIRTY_CLIENTS_NOCODE;
- if (!global_dirty_log) {
+ if (!global_dirty_tracking) {
clients &= ~(1 << DIRTY_MEMORY_MIGRATION);
}
diff --git a/migration/ram.c b/migration/ram.c
index bb90882..ae2601b 100644
--- a/migration/ram.c
+++ b/migration/ram.c
@@ -2216,7 +2216,14 @@
/* caller have hold iothread lock or is in a bh, so there is
* no writing race against the migration bitmap
*/
- memory_global_dirty_log_stop();
+ if (global_dirty_tracking & GLOBAL_DIRTY_MIGRATION) {
+ /*
+ * do not stop dirty log without starting it, since
+ * memory_global_dirty_log_stop will assert that
+ * memory_global_dirty_log_start/stop used in pairs
+ */
+ memory_global_dirty_log_stop(GLOBAL_DIRTY_MIGRATION);
+ }
}
RAMBLOCK_FOREACH_NOT_IGNORED(block) {
@@ -2678,7 +2685,7 @@
ram_list_init_bitmaps();
/* We don't use dirty log with background snapshots */
if (!migrate_background_snapshot()) {
- memory_global_dirty_log_start();
+ memory_global_dirty_log_start(GLOBAL_DIRTY_MIGRATION);
migration_bitmap_sync_precopy(rs);
}
}
@@ -3434,7 +3441,7 @@
/* Discard this dirty bitmap record */
bitmap_zero(block->bmap, block->max_length >> TARGET_PAGE_BITS);
}
- memory_global_dirty_log_start();
+ memory_global_dirty_log_start(GLOBAL_DIRTY_MIGRATION);
}
ram_state->migration_dirty_pages = 0;
qemu_mutex_unlock_ramlist();
@@ -3446,7 +3453,7 @@
{
RAMBlock *block;
- memory_global_dirty_log_stop();
+ memory_global_dirty_log_stop(GLOBAL_DIRTY_MIGRATION);
RAMBLOCK_FOREACH_NOT_IGNORED(block) {
g_free(block->bmap);
block->bmap = NULL;
diff --git a/softmmu/memory.c b/softmmu/memory.c
index e5826fa..f2ac0d2 100644
--- a/softmmu/memory.c
+++ b/softmmu/memory.c
@@ -39,7 +39,7 @@
static unsigned memory_region_transaction_depth;
static bool memory_region_update_pending;
static bool ioeventfd_update_pending;
-bool global_dirty_log;
+unsigned int global_dirty_tracking;
static QTAILQ_HEAD(, MemoryListener) memory_listeners
= QTAILQ_HEAD_INITIALIZER(memory_listeners);
@@ -1821,7 +1821,7 @@
uint8_t mask = mr->dirty_log_mask;
RAMBlock *rb = mr->ram_block;
- if (global_dirty_log && ((rb && qemu_ram_is_migratable(rb)) ||
+ if (global_dirty_tracking && ((rb && qemu_ram_is_migratable(rb)) ||
memory_region_is_iommu(mr))) {
mask |= (1 << DIRTY_MEMORY_MIGRATION);
}
@@ -2760,14 +2760,18 @@
static VMChangeStateEntry *vmstate_change;
-void memory_global_dirty_log_start(void)
+void memory_global_dirty_log_start(unsigned int flags)
{
if (vmstate_change) {
qemu_del_vm_change_state_handler(vmstate_change);
vmstate_change = NULL;
}
- global_dirty_log = true;
+ assert(flags && !(flags & (~GLOBAL_DIRTY_MASK)));
+ assert(!(global_dirty_tracking & flags));
+ global_dirty_tracking |= flags;
+
+ trace_global_dirty_changed(global_dirty_tracking);
MEMORY_LISTENER_CALL_GLOBAL(log_global_start, Forward);
@@ -2777,9 +2781,13 @@
memory_region_transaction_commit();
}
-static void memory_global_dirty_log_do_stop(void)
+static void memory_global_dirty_log_do_stop(unsigned int flags)
{
- global_dirty_log = false;
+ assert(flags && !(flags & (~GLOBAL_DIRTY_MASK)));
+ assert((global_dirty_tracking & flags) == flags);
+ global_dirty_tracking &= ~flags;
+
+ trace_global_dirty_changed(global_dirty_tracking);
/* Refresh DIRTY_MEMORY_MIGRATION bit. */
memory_region_transaction_begin();
@@ -2792,8 +2800,9 @@
static void memory_vm_change_state_handler(void *opaque, bool running,
RunState state)
{
+ unsigned int flags = (unsigned int)(uintptr_t)opaque;
if (running) {
- memory_global_dirty_log_do_stop();
+ memory_global_dirty_log_do_stop(flags);
if (vmstate_change) {
qemu_del_vm_change_state_handler(vmstate_change);
@@ -2802,18 +2811,19 @@
}
}
-void memory_global_dirty_log_stop(void)
+void memory_global_dirty_log_stop(unsigned int flags)
{
if (!runstate_is_running()) {
if (vmstate_change) {
return;
}
vmstate_change = qemu_add_vm_change_state_handler(
- memory_vm_change_state_handler, NULL);
+ memory_vm_change_state_handler,
+ (void *)(uintptr_t)flags);
return;
}
- memory_global_dirty_log_do_stop();
+ memory_global_dirty_log_do_stop(flags);
}
static void listener_add_address_space(MemoryListener *listener,
@@ -2825,7 +2835,7 @@
if (listener->begin) {
listener->begin(listener);
}
- if (global_dirty_log) {
+ if (global_dirty_tracking) {
if (listener->log_global_start) {
listener->log_global_start(listener);
}
diff --git a/softmmu/trace-events b/softmmu/trace-events
index bf14699..9c88887 100644
--- a/softmmu/trace-events
+++ b/softmmu/trace-events
@@ -19,6 +19,7 @@
flatview_new(void *view, void *root) "%p (root %p)"
flatview_destroy(void *view, void *root) "%p (root %p)"
flatview_destroy_rcu(void *view, void *root) "%p (root %p)"
+global_dirty_changed(unsigned int bitmask) "bitmask 0x%"PRIx32
# softmmu.c
vm_stop_flush_all(int ret) "ret %d"
