pve-qemu-qoup/debian/patches/pve/0011-convert-savevm-async-to-threads.patch
2017-09-08 09:44:31 +02:00

235 lines
7.4 KiB
Diff

From bed6817c14a520409f4ffee05e635c988c8b5994 Mon Sep 17 00:00:00 2001
From: Wolfgang Bumiller <w.bumiller@proxmox.com>
Date: Tue, 8 Nov 2016 11:13:06 +0100
Subject: [PATCH 11/28] convert savevm-async to threads
---
savevm-async.c | 144 +++++++++++++++++++++++++++++++++++----------------------
1 file changed, 88 insertions(+), 56 deletions(-)
diff --git a/savevm-async.c b/savevm-async.c
index 5fcb56d373..97d51d3edd 100644
--- a/savevm-async.c
+++ b/savevm-async.c
@@ -48,6 +48,8 @@ static struct SnapshotState {
int saved_vm_running;
QEMUFile *file;
int64_t total_time;
+ QEMUBH *cleanup_bh;
+ QemuThread thread;
} snap_state;
SaveVMInfo *qmp_query_savevm(Error **errp)
@@ -135,19 +137,6 @@ static void save_snapshot_error(const char *fmt, ...)
g_free (msg);
snap_state.state = SAVE_STATE_ERROR;
-
- save_snapshot_cleanup();
-}
-
-static void save_snapshot_completed(void)
-{
- DPRINTF("save_snapshot_completed\n");
-
- if (save_snapshot_cleanup() < 0) {
- snap_state.state = SAVE_STATE_ERROR;
- } else {
- snap_state.state = SAVE_STATE_COMPLETED;
- }
}
static int block_state_close(void *opaque)
@@ -156,51 +145,90 @@ static int block_state_close(void *opaque)
return blk_flush(snap_state.target);
}
+typedef struct BlkRwCo {
+ int64_t offset;
+ QEMUIOVector *qiov;
+ int ret;
+} BlkRwCo;
+
+static void block_state_write_entry(void *opaque) {
+ BlkRwCo *rwco = opaque;
+ rwco->ret = blk_co_pwritev(snap_state.target, rwco->offset, rwco->qiov->size,
+ rwco->qiov, 0);
+}
+
static ssize_t block_state_writev_buffer(void *opaque, struct iovec *iov,
int iovcnt, int64_t pos)
{
- int ret;
QEMUIOVector qiov;
+ AioContext *aio_context;
+ Coroutine *co;
+ BlkRwCo rwco;
+
+ assert(pos == snap_state.bs_pos);
+ rwco = (BlkRwCo) {
+ .offset = pos,
+ .qiov = &qiov,
+ .ret = NOT_DONE,
+ };
qemu_iovec_init_external(&qiov, iov, iovcnt);
- ret = blk_co_pwritev(snap_state.target, pos, qiov.size, &qiov, 0);
- if (ret < 0) {
- return ret;
+
+ aio_context = blk_get_aio_context(snap_state.target);
+ aio_context_acquire(aio_context);
+ co = qemu_coroutine_create(&block_state_write_entry, &rwco);
+ qemu_coroutine_enter(co);
+ while (rwco.ret == NOT_DONE) {
+ aio_poll(aio_context, true);
}
+ aio_context_release(aio_context);
+
snap_state.bs_pos += qiov.size;
return qiov.size;
}
-static int store_and_stop(void) {
- if (global_state_store()) {
- save_snapshot_error("Error saving global state");
- return 1;
+static void process_savevm_cleanup(void *opaque)
+{
+ int ret;
+ qemu_bh_delete(snap_state.cleanup_bh);
+ snap_state.cleanup_bh = NULL;
+ qemu_mutex_unlock_iothread();
+ qemu_thread_join(&snap_state.thread);
+ qemu_mutex_lock_iothread();
+ ret = save_snapshot_cleanup();
+ if (ret < 0) {
+ save_snapshot_error("save_snapshot_cleanup error %d", ret);
+ } else if (snap_state.state == SAVE_STATE_ACTIVE) {
+ snap_state.state = SAVE_STATE_COMPLETED;
+ } else {
+ save_snapshot_error("process_savevm_cleanup: invalid state: %d",
+ snap_state.state);
}
- if (runstate_is_running()) {
- vm_stop(RUN_STATE_SAVE_VM);
+ if (snap_state.saved_vm_running) {
+ vm_start();
+ snap_state.saved_vm_running = false;
}
- return 0;
}
-static void process_savevm_co(void *opaque)
+static void *process_savevm_thread(void *opaque)
{
int ret;
int64_t maxlen;
+
MigrationParams params = {
.blk = 0,
.shared = 0
};
- snap_state.state = SAVE_STATE_ACTIVE;
+ rcu_register_thread();
- qemu_mutex_unlock_iothread();
qemu_savevm_state_header(snap_state.file);
ret = qemu_savevm_state_begin(snap_state.file, &params);
- qemu_mutex_lock_iothread();
if (ret < 0) {
save_snapshot_error("qemu_savevm_state_begin failed");
- return;
+ rcu_unregister_thread();
+ return NULL;
}
while (snap_state.state == SAVE_STATE_ACTIVE) {
@@ -209,41 +237,43 @@ static void process_savevm_co(void *opaque)
qemu_savevm_state_pending(snap_state.file, 0, &pend_nonpost, &pend_post);
pending_size = pend_post + pend_nonpost;
- if (pending_size) {
- ret = qemu_savevm_state_iterate(snap_state.file, false);
- if (ret < 0) {
- save_snapshot_error("qemu_savevm_state_iterate error %d", ret);
- break;
- }
- DPRINTF("savevm inerate pending size %lu ret %d\n", pending_size, ret);
+ maxlen = blk_getlength(snap_state.target) - 30*1024*1024;
+
+ if (pending_size > 400000 && snap_state.bs_pos + pending_size < maxlen) {
+ qemu_mutex_lock_iothread();
+ ret = qemu_savevm_state_iterate(snap_state.file, false);
+ if (ret < 0) {
+ save_snapshot_error("qemu_savevm_state_iterate error %d", ret);
+ break;
+ }
+ qemu_mutex_unlock_iothread();
+ DPRINTF("savevm inerate pending size %lu ret %d\n", pending_size, ret);
} else {
- DPRINTF("done iterating\n");
- if (store_and_stop())
+ qemu_mutex_lock_iothread();
+ qemu_system_wakeup_request(QEMU_WAKEUP_REASON_OTHER);
+ ret = global_state_store();
+ if (ret) {
+ save_snapshot_error("global_state_store error %d", ret);
break;
+ }
+ ret = vm_stop_force_state(RUN_STATE_FINISH_MIGRATE);
+ if (ret < 0) {
+ save_snapshot_error("vm_stop_force_state error %d", ret);
+ break;
+ }
DPRINTF("savevm inerate finished\n");
qemu_savevm_state_complete_precopy(snap_state.file, false);
+ qemu_savevm_state_cleanup();
DPRINTF("save complete\n");
- save_snapshot_completed();
break;
}
-
- /* stop the VM if we get to the end of available space,
- * or if pending_size is just a few MB
- */
- maxlen = blk_getlength(snap_state.target) - 30*1024*1024;
- if ((pending_size < 100000) ||
- ((snap_state.bs_pos + pending_size) >= maxlen)) {
- if (store_and_stop())
- break;
- }
}
- if(snap_state.state == SAVE_STATE_CANCELLED) {
- save_snapshot_completed();
- Error *errp = NULL;
- qmp_savevm_end(&errp);
- }
+ qemu_bh_schedule(snap_state.cleanup_bh);
+ qemu_mutex_unlock_iothread();
+ rcu_unregister_thread();
+ return NULL;
}
static const QEMUFileOps block_file_ops = {
@@ -306,8 +336,10 @@ void qmp_savevm_start(bool has_statefile, const char *statefile, Error **errp)
error_setg(&snap_state.blocker, "block device is in use by savevm");
blk_op_block_all(snap_state.target, snap_state.blocker);
- Coroutine *co = qemu_coroutine_create(process_savevm_co, NULL);
- qemu_coroutine_enter(co);
+ snap_state.state = SAVE_STATE_ACTIVE;
+ snap_state.cleanup_bh = qemu_bh_new(process_savevm_cleanup, &snap_state);
+ qemu_thread_create(&snap_state.thread, "savevm-async", process_savevm_thread,
+ NULL, QEMU_THREAD_JOINABLE);
return;
--
2.11.0