As we really know how much space we have free in the buffers, we can
send that information instead of guessing how much we can sent each time.
Signed-off-by: Juan Quintela <quint...@redhat.com>
---
arch_init.c | 20 +++++++++-----------
block-migration.c | 2 +-
migration.c | 3 ++-
savevm.c | 10 +++++++---
sysemu.h | 2 +-
vmstate.h | 2 +-
6 files changed, 21 insertions(+), 18 deletions(-)
diff --git a/arch_init.c b/arch_init.c
index 723529a..f5f9324 100644
--- a/arch_init.c
+++ b/arch_init.c
@@ -627,9 +627,12 @@ static int ram_save_setup(QEMUFile *f, void *opaque)
return 0;
}
-static int ram_save_iterate(QEMUFile *f, void *opaque)
+/* Maximum size for a transmited page
+ header + len + idstr + page size */
+#define MAX_PAGE_SIZE ( 8 + 1 + 256 + TARGET_PAGE_SIZE)
+
+static int ram_save_iterate(QEMUFile *f, void *opaque, uint64_t free_space)
{
- int ret;
int i;
int64_t t0;
int total_sent = 0;
@@ -642,15 +645,15 @@ static int ram_save_iterate(QEMUFile *f, void *opaque)
t0 = qemu_get_clock_ns(rt_clock);
i = 0;
- while ((ret = qemu_file_rate_limit(f)) == 0) {
- int bytes_sent;
-
- bytes_sent = ram_save_block(f, false);
+ /* We need space for at least one page and end of section marker */
+ while (free_space > MAX_PAGE_SIZE + 8) {
+ int bytes_sent = ram_save_block(f, false);
/* no more blocks to sent */
if (bytes_sent == 0) {
break;
}
total_sent += bytes_sent;
+ free_space -= bytes_sent;
acct_info.iterations++;
/* we want to check in the 1st loop, just in case it was the 1st time
and we had to sync the dirty bitmap.
@@ -668,11 +671,6 @@ static int ram_save_iterate(QEMUFile *f, void *opaque)
i++;
}
- if (ret < 0) {
- bytes_transferred += total_sent;
- return ret;
- }
-
qemu_mutex_unlock_ramlist();
qemu_put_be64(f, RAM_SAVE_FLAG_EOS);
total_sent += 8;
diff --git a/block-migration.c b/block-migration.c
index 5db01fe..b11d7e0 100644
--- a/block-migration.c
+++ b/block-migration.c
@@ -535,7 +535,7 @@ static int block_save_setup(QEMUFile *f, void *opaque)
return 0;
}
-static int block_save_iterate(QEMUFile *f, void *opaque)
+static int block_save_iterate(QEMUFile *f, void *opaque, uint64_t free_space)
{
int ret;
diff --git a/migration.c b/migration.c
index 216356d..d59f7b4 100644
--- a/migration.c
+++ b/migration.c
@@ -694,6 +694,7 @@ static void *buffered_file_thread(void *opaque)
while (true) {
int64_t current_time = qemu_get_clock_ms(rt_clock);
uint64_t pending_size;
+ size_t free_space = s->buffer_capacity - s->buffer_size;
qemu_mutex_lock_iothread();
if (m->state != MIG_STATE_ACTIVE) {
@@ -710,7 +711,7 @@ static void *buffered_file_thread(void *opaque)
pending_size = qemu_savevm_state_pending(m->file, max_size);
DPRINTF("pending size %lu max %lu\n", pending_size, max_size);
if (pending_size && pending_size >= max_size) {
- ret = qemu_savevm_state_iterate(m->file);
+ ret = qemu_savevm_state_iterate(m->file, free_space);
if (ret < 0) {
qemu_mutex_unlock_iothread();
break;
diff --git a/savevm.c b/savevm.c
index f6e91cf..4b7715a 100644
--- a/savevm.c
+++ b/savevm.c
@@ -1655,10 +1655,11 @@ int qemu_savevm_state_begin(QEMUFile *f,
* 0 : We haven't finished, caller have to go again
* 1 : We have finished, we can go to complete phase
*/
-int qemu_savevm_state_iterate(QEMUFile *f)
+int qemu_savevm_state_iterate(QEMUFile *f, uint64_t free_space)
{
SaveStateEntry *se;
int ret = 1;
+ size_t remaining_space = free_space;
QTAILQ_FOREACH(se, &savevm_handlers, entry) {
if (!se->ops || !se->ops->save_live_iterate) {
@@ -1675,9 +1676,11 @@ int qemu_savevm_state_iterate(QEMUFile *f)
trace_savevm_section_start();
/* Section type */
qemu_put_byte(f, QEMU_VM_SECTION_PART);
+ remaining_space -= 1;
qemu_put_be32(f, se->section_id);
+ remaining_space -= 4;
- ret = se->ops->save_live_iterate(f, se->opaque);
+ ret = se->ops->save_live_iterate(f, se->opaque, remaining_space);
trace_savevm_section_end(se->section_id);
if (ret <= 0) {
@@ -1687,6 +1690,7 @@ int qemu_savevm_state_iterate(QEMUFile *f)
synchronized over and over again. */
break;
}
+ remaining_space -= ret;
}
if (ret != 0) {
return ret;
@@ -1802,7 +1806,7 @@ static int qemu_savevm_state(QEMUFile *f)
goto out;
do {
- ret = qemu_savevm_state_iterate(f);
+ ret = qemu_savevm_state_iterate(f, SIZE_MAX);
if (ret < 0)
goto out;
} while (ret == 0);
diff --git a/sysemu.h b/sysemu.h
index 7832c69..7fc5124 100644
--- a/sysemu.h
+++ b/sysemu.h
@@ -75,7 +75,7 @@ void qemu_announce_self(void);
bool qemu_savevm_state_blocked(Error **errp);
int qemu_savevm_state_begin(QEMUFile *f,
const MigrationParams *params);
-int qemu_savevm_state_iterate(QEMUFile *f);
+int qemu_savevm_state_iterate(QEMUFile *f, uint64_t free_space);
int qemu_savevm_state_complete(QEMUFile *f);
void qemu_savevm_state_cancel(QEMUFile *f);
uint64_t qemu_savevm_state_pending(QEMUFile *f, uint64_t max_size);
diff --git a/vmstate.h b/vmstate.h
index f27276c..0b55cf4 100644
--- a/vmstate.h
+++ b/vmstate.h
@@ -33,7 +33,7 @@ typedef struct SaveVMHandlers {
void (*set_params)(const MigrationParams *params, void * opaque);
SaveStateHandler *save_state;
int (*save_live_setup)(QEMUFile *f, void *opaque);
- int (*save_live_iterate)(QEMUFile *f, void *opaque);
+ int (*save_live_iterate)(QEMUFile *f, void *opaque, uint64_t free_space);
int (*save_live_complete)(QEMUFile *f, void *opaque);
uint64_t (*save_live_pending)(QEMUFile *f, void *opaque, uint64_t
max_size);
void (*cancel)(void *opaque);
--
1.7.11.7
