Re: [Qemu-devel] Re: [PATCH 07/18] Introduce fault tolerant VM transaction QEMUFile and ft_mode.
2011/2/23 ya su suya94...@gmail.com:
Yoshi:
thanks for your explaining.
if you introduce a new stage as 3, I think stage 1 also need to change as
it will mark all pages dirty.
looking forward to your new patch update.
Unless there're strong comments from others, I won't put it in
this series though because I don't want to touch other components
as much as possible this time.
Yoshi
Green.
2011/2/21 Yoshiaki Tamura tamura.yoshi...@lab.ntt.co.jp
Hi Green,
2011/2/21 ya su suya94...@gmail.com:
Yoshiaki:
I have one question about ram_save_live, during migration 3
stage(completation stage), it will call
cpu_physical_memory_set_dirty_tracking(0) to stop recording ram dirty
pages.
at the end of migrate_ft_trans_connect function, it will invoke
vm_start(),
at this time, cpu_physical_memory_set_dirty_tracking(1) is not called
yet,
so there may have some ram pages not recorded when
qemu_savevm_trans_begin
is called. I think you need calll
cpu_physical_memory_set_dirty_tracking(1) in migrate_ft_trans_connect
function, Am I right?
Thank you for taking a look.
When qemu_savevm_trans_begin is called for the first time, it
calls ram_save_live with stage 1, that sends all pages and sets
dirty tracking, so there won't be missing pages. Note that
event-tap is turned on by then, meaning no outputs are sent before
finishing the first transaction. I understand that this
implementation is inefficient, and planning to introduce a new
stage that is almost same as stage 3 but keeps dirty tracking in
the future.
Thanks,
Yoshi
BR
Green.
2011/2/10 Yoshiaki Tamura tamura.yoshi...@lab.ntt.co.jp
This code implements VM transaction protocol. Like buffered_file, it
sits between savevm and migration layer. With this architecture, VM
transaction protocol is implemented mostly independent from other
existing code.
Signed-off-by: Yoshiaki Tamura tamura.yoshi...@lab.ntt.co.jp
Signed-off-by: OHMURA Kei ohmura@lab.ntt.co.jp
---
Makefile.objs | 1 +
ft_trans_file.c | 624
+++
ft_trans_file.h | 72 +++
migration.c | 3 +
trace-events | 15 ++
5 files changed, 715 insertions(+), 0 deletions(-)
create mode 100644 ft_trans_file.c
create mode 100644 ft_trans_file.h
diff --git a/Makefile.objs b/Makefile.objs
index 353b1a8..04148b5 100644
--- a/Makefile.objs
+++ b/Makefile.objs
@@ -100,6 +100,7 @@ common-obj-y += msmouse.o ps2.o
common-obj-y += qdev.o qdev-properties.o
common-obj-y += block-migration.o
common-obj-y += pflib.o
+common-obj-y += ft_trans_file.o
common-obj-$(CONFIG_BRLAPI) += baum.o
common-obj-$(CONFIG_POSIX) += migration-exec.o migration-unix.o
migration-fd.o
diff --git a/ft_trans_file.c b/ft_trans_file.c
new file mode 100644
index 000..2b42b95
--- /dev/null
+++ b/ft_trans_file.c
@@ -0,0 +1,624 @@
+/*
+ * Fault tolerant VM transaction QEMUFile
+ *
+ * Copyright (c) 2010 Nippon Telegraph and Telephone Corporation.
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2.
See
+ * the COPYING file in the top-level directory.
+ *
+ * This source code is based on buffered_file.c.
+ * Copyright IBM, Corp. 2008
+ * Authors:
+ * Anthony Liguori aligu...@us.ibm.com
+ */
+
+#include qemu-common.h
+#include qemu-error.h
+#include hw/hw.h
+#include qemu-timer.h
+#include sysemu.h
+#include qemu-char.h
+#include trace.h
+#include ft_trans_file.h
+
+typedef struct FtTransHdr
+{
+ uint16_t cmd;
+ uint16_t id;
+ uint32_t seq;
+ uint32_t payload_len;
+} FtTransHdr;
+
+typedef struct QEMUFileFtTrans
+{
+ FtTransPutBufferFunc *put_buffer;
+ FtTransGetBufferFunc *get_buffer;
+ FtTransPutReadyFunc *put_ready;
+ FtTransGetReadyFunc *get_ready;
+ FtTransWaitForUnfreezeFunc *wait_for_unfreeze;
+ FtTransCloseFunc *close;
+ void *opaque;
+ QEMUFile *file;
+
+ enum QEMU_VM_TRANSACTION_STATE state;
+ uint32_t seq;
+ uint16_t id;
+
+ int has_error;
+
+ bool freeze_output;
+ bool freeze_input;
+ bool rate_limit;
+ bool is_sender;
+ bool is_payload;
+
+ uint8_t *buf;
+ size_t buf_max_size;
+ size_t put_offset;
+ size_t get_offset;
+
+ FtTransHdr header;
+ size_t header_offset;
+} QEMUFileFtTrans;
+
+#define IO_BUF_SIZE 32768
+
+static void ft_trans_append(QEMUFileFtTrans *s,
+ const uint8_t *buf, size_t size)
+{
+ if (size (s-buf_max_size - s-put_offset)) {
+ trace_ft_trans_realloc(s-buf_max_size, size + 1024);
+ s-buf_max_size += size + 1024;
+ s-buf = qemu_realloc(s-buf, s-buf_max_size);
+ }
+
+ trace_ft_trans_append(size);
+ memcpy(s-buf + s-put_offset, buf, size);
+ s-put_offset += size;
Re: [Qemu-devel] Re: [PATCH 07/18] Introduce fault tolerant VM transaction QEMUFile and ft_mode.
Hi Green,
2011/2/21 ya su suya94...@gmail.com:
Yoshiaki:
I have one question about ram_save_live, during migration 3
stage(completation stage), it will call
cpu_physical_memory_set_dirty_tracking(0) to stop recording ram dirty pages.
at the end of migrate_ft_trans_connect function, it will invoke vm_start(),
at this time, cpu_physical_memory_set_dirty_tracking(1) is not called yet,
so there may have some ram pages not recorded when qemu_savevm_trans_begin
is called. I think you need calll
cpu_physical_memory_set_dirty_tracking(1) in migrate_ft_trans_connect
function, Am I right?
Thank you for taking a look.
When qemu_savevm_trans_begin is called for the first time, it
calls ram_save_live with stage 1, that sends all pages and sets
dirty tracking, so there won't be missing pages. Note that
event-tap is turned on by then, meaning no outputs are sent before
finishing the first transaction. I understand that this
implementation is inefficient, and planning to introduce a new
stage that is almost same as stage 3 but keeps dirty tracking in
the future.
Thanks,
Yoshi
BR
Green.
2011/2/10 Yoshiaki Tamura tamura.yoshi...@lab.ntt.co.jp
This code implements VM transaction protocol. Like buffered_file, it
sits between savevm and migration layer. With this architecture, VM
transaction protocol is implemented mostly independent from other
existing code.
Signed-off-by: Yoshiaki Tamura tamura.yoshi...@lab.ntt.co.jp
Signed-off-by: OHMURA Kei ohmura@lab.ntt.co.jp
---
Makefile.objs | 1 +
ft_trans_file.c | 624
+++
ft_trans_file.h | 72 +++
migration.c | 3 +
trace-events | 15 ++
5 files changed, 715 insertions(+), 0 deletions(-)
create mode 100644 ft_trans_file.c
create mode 100644 ft_trans_file.h
diff --git a/Makefile.objs b/Makefile.objs
index 353b1a8..04148b5 100644
--- a/Makefile.objs
+++ b/Makefile.objs
@@ -100,6 +100,7 @@ common-obj-y += msmouse.o ps2.o
common-obj-y += qdev.o qdev-properties.o
common-obj-y += block-migration.o
common-obj-y += pflib.o
+common-obj-y += ft_trans_file.o
common-obj-$(CONFIG_BRLAPI) += baum.o
common-obj-$(CONFIG_POSIX) += migration-exec.o migration-unix.o
migration-fd.o
diff --git a/ft_trans_file.c b/ft_trans_file.c
new file mode 100644
index 000..2b42b95
--- /dev/null
+++ b/ft_trans_file.c
@@ -0,0 +1,624 @@
+/*
+ * Fault tolerant VM transaction QEMUFile
+ *
+ * Copyright (c) 2010 Nippon Telegraph and Telephone Corporation.
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2. See
+ * the COPYING file in the top-level directory.
+ *
+ * This source code is based on buffered_file.c.
+ * Copyright IBM, Corp. 2008
+ * Authors:
+ * Anthony Liguori aligu...@us.ibm.com
+ */
+
+#include qemu-common.h
+#include qemu-error.h
+#include hw/hw.h
+#include qemu-timer.h
+#include sysemu.h
+#include qemu-char.h
+#include trace.h
+#include ft_trans_file.h
+
+typedef struct FtTransHdr
+{
+ uint16_t cmd;
+ uint16_t id;
+ uint32_t seq;
+ uint32_t payload_len;
+} FtTransHdr;
+
+typedef struct QEMUFileFtTrans
+{
+ FtTransPutBufferFunc *put_buffer;
+ FtTransGetBufferFunc *get_buffer;
+ FtTransPutReadyFunc *put_ready;
+ FtTransGetReadyFunc *get_ready;
+ FtTransWaitForUnfreezeFunc *wait_for_unfreeze;
+ FtTransCloseFunc *close;
+ void *opaque;
+ QEMUFile *file;
+
+ enum QEMU_VM_TRANSACTION_STATE state;
+ uint32_t seq;
+ uint16_t id;
+
+ int has_error;
+
+ bool freeze_output;
+ bool freeze_input;
+ bool rate_limit;
+ bool is_sender;
+ bool is_payload;
+
+ uint8_t *buf;
+ size_t buf_max_size;
+ size_t put_offset;
+ size_t get_offset;
+
+ FtTransHdr header;
+ size_t header_offset;
+} QEMUFileFtTrans;
+
+#define IO_BUF_SIZE 32768
+
+static void ft_trans_append(QEMUFileFtTrans *s,
+ const uint8_t *buf, size_t size)
+{
+ if (size (s-buf_max_size - s-put_offset)) {
+ trace_ft_trans_realloc(s-buf_max_size, size + 1024);
+ s-buf_max_size += size + 1024;
+ s-buf = qemu_realloc(s-buf, s-buf_max_size);
+ }
+
+ trace_ft_trans_append(size);
+ memcpy(s-buf + s-put_offset, buf, size);
+ s-put_offset += size;
+}
+
+static void ft_trans_flush(QEMUFileFtTrans *s)
+{
+ size_t offset = 0;
+
+ if (s-has_error) {
+ error_report(flush when error %d, bailing, s-has_error);
+ return;
+ }
+
+ while (offset s-put_offset) {
+ ssize_t ret;
+
+ ret = s-put_buffer(s-opaque, s-buf + offset, s-put_offset -
offset);
+ if (ret == -EAGAIN) {
+ break;
+ }
+
+ if (ret = 0) {
+ error_report(error flushing data, %s, strerror(errno));
+ s-has_error = FT_TRANS_ERR_FLUSH;
+ break;
+ } else {
+ offset +=
