[PULL 0/5] Migration 20230215 patches

[PULL 0/5] Migration 20230215 patches

[Juan Quintela]

The following changes since commit 6a50f64ca01d0a7b97f14f069762bfd88160f31e:

  Merge tag 'pull-request-2023-02-14' of https://gitlab.com/thuth/qemu into staging (2023-02-14 14:46:10 +0000)

are available in the Git repository at:

  https://gitlab.com/juan.quintela/qemu.git tags/migration-20230215-pull-request

for you to fetch changes up to 24beea4efe6e6b65fd6248ede936cd3278b2bf8a:

  migration: Rename res_{postcopy,precopy}_only (2023-02-15 20:04:30 +0100)

----------------------------------------------------------------
Migration Pull request

This pull request contains:

* Add qemu_file_get_to_fd() a.k.a. make vfio happy(Avihai)
* migration/block is now DPRINTF() free zone (Philippe)
* remove res_compat and improve docs (me)

Please apply.

----------------------------------------------------------------

Avihai Horon (1):
  migration/qemu-file: Add qemu_file_get_to_fd()

Juan Quintela (3):
  migration: In case of postcopy, the memory ends in res_postcopy_only
  migration: Remove unused res_compatible
  migration: Rename res_{postcopy,precopy}_only

Philippe Mathieu-Daudé (1):
  migration/block: Convert remaining DPRINTF() debug macro to trace
    events

 include/migration/register.h   | 30 +++++++++++++++---------------
 migration/qemu-file.h          |  1 +
 migration/savevm.h             | 10 ++++------
 hw/s390x/s390-stattrib.c       |  8 +++-----
 hw/vfio/migration.c            | 11 ++++-------
 migration/block-dirty-bitmap.c |  7 +++----
 migration/block.c              | 20 ++++----------------
 migration/migration.c          | 20 +++++++++-----------
 migration/qemu-file.c          | 34 ++++++++++++++++++++++++++++++++++
 migration/ram.c                | 20 ++++++++------------
 migration/savevm.c             | 28 ++++++++++------------------
 hw/vfio/trace-events           |  2 +-
 migration/trace-events         |  5 +++--
 13 files changed, 99 insertions(+), 97 deletions(-)

-- 
2.39.1

[PULL 1/5] migration/qemu-file: Add qemu_file_get_to_fd()

[Juan Quintela]

From: Avihai Horon <avihaih@nvidia.com>

Add new function qemu_file_get_to_fd() that allows reading data from
QEMUFile and writing it straight into a given fd.

This will be used later in VFIO migration code.

Signed-off-by: Avihai Horon <avihaih@nvidia.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
---
 migration/qemu-file.h |  1 +
 migration/qemu-file.c | 34 ++++++++++++++++++++++++++++++++++
 2 files changed, 35 insertions(+)

diff --git a/migration/qemu-file.h b/migration/qemu-file.h
index fa13d04d78..9d0155a2a1 100644
--- a/migration/qemu-file.h
+++ b/migration/qemu-file.h
@@ -148,6 +148,7 @@ int qemu_file_shutdown(QEMUFile *f);
 QEMUFile *qemu_file_get_return_path(QEMUFile *f);
 void qemu_fflush(QEMUFile *f);
 void qemu_file_set_blocking(QEMUFile *f, bool block);
+int qemu_file_get_to_fd(QEMUFile *f, int fd, size_t size);
 
 void ram_control_before_iterate(QEMUFile *f, uint64_t flags);
 void ram_control_after_iterate(QEMUFile *f, uint64_t flags);
diff --git a/migration/qemu-file.c b/migration/qemu-file.c
index 2d5f74ffc2..102ab3b439 100644
--- a/migration/qemu-file.c
+++ b/migration/qemu-file.c
@@ -940,3 +940,37 @@ QIOChannel *qemu_file_get_ioc(QEMUFile *file)
 {
     return file->ioc;
 }
+
+/*
+ * Read size bytes from QEMUFile f and write them to fd.
+ */
+int qemu_file_get_to_fd(QEMUFile *f, int fd, size_t size)
+{
+    while (size) {
+        size_t pending = f->buf_size - f->buf_index;
+        ssize_t rc;
+
+        if (!pending) {
+            rc = qemu_fill_buffer(f);
+            if (rc < 0) {
+                return rc;
+            }
+            if (rc == 0) {
+                return -EIO;
+            }
+            continue;
+        }
+
+        rc = write(fd, f->buf + f->buf_index, MIN(pending, size));
+        if (rc < 0) {
+            return -errno;
+        }
+        if (rc == 0) {
+            return -EIO;
+        }
+        f->buf_index += rc;
+        size -= rc;
+    }
+
+    return 0;
+}
-- 
2.39.1

[PULL 2/5] migration/block: Convert remaining DPRINTF() debug macro to trace events

[Juan Quintela]

From: Philippe Mathieu-Daudé <philmd@linaro.org>

Finish the conversion from commit fe80c0241d
("migration: using trace_ to replace DPRINTF").

Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
---
 migration/block.c      | 12 +-----------
 migration/trace-events |  1 +
 2 files changed, 2 insertions(+), 11 deletions(-)

diff --git a/migration/block.c b/migration/block.c
index 29f69025af..b5ce506d01 100644
--- a/migration/block.c
+++ b/migration/block.c
@@ -42,16 +42,6 @@
 #define MAX_IO_BUFFERS 512
 #define MAX_PARALLEL_IO 16
 
-/* #define DEBUG_BLK_MIGRATION */
-
-#ifdef DEBUG_BLK_MIGRATION
-#define DPRINTF(fmt, ...) \
-    do { printf("blk_migration: " fmt, ## __VA_ARGS__); } while (0)
-#else
-#define DPRINTF(fmt, ...) \
-    do { } while (0)
-#endif
-
 typedef struct BlkMigDevState {
     /* Written during setup phase.  Can be read without a lock.  */
     BlockBackend *blk;
@@ -502,7 +492,7 @@ static int blk_mig_save_bulked_block(QEMUFile *f)
         block_mig_state.prev_progress = progress;
         qemu_put_be64(f, (progress << BDRV_SECTOR_BITS)
                          | BLK_MIG_FLAG_PROGRESS);
-        DPRINTF("Completed %d %%\r", progress);
+        trace_migration_block_progression(progress);
     }
 
     return ret;
diff --git a/migration/trace-events b/migration/trace-events
index 67b65a70ff..b20e1271bc 100644
--- a/migration/trace-events
+++ b/migration/trace-events
@@ -357,6 +357,7 @@ migration_block_flush_blks(const char *action, int submitted, int read_done, int
 migration_block_save(const char *mig_stage, int submitted, int transferred) "Enter save live %s submitted %d transferred %d"
 migration_block_save_complete(void) "Block migration completed"
 migration_block_state_pending(uint64_t pending) "Enter save live pending  %" PRIu64
+migration_block_progression(unsigned percent) "Completed %u%%"
 
 # page_cache.c
 migration_pagecache_init(int64_t max_num_items) "Setting cache buckets to %" PRId64
-- 
2.39.1

[PULL 3/5] migration: In case of postcopy, the memory ends in res_postcopy_only

[Juan Quintela]

So remove last assignation of res_compatible.

Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Signed-off-by: Juan Quintela <quintela@redhat.com>
---
 migration/ram.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/migration/ram.c b/migration/ram.c
index 521912385d..ecf697a58d 100644
--- a/migration/ram.c
+++ b/migration/ram.c
@@ -3528,7 +3528,7 @@ static void ram_state_pending_exact(void *opaque,
 
     if (migrate_postcopy_ram()) {
         /* We can do postcopy, and all the data is postcopiable */
-        *res_compatible += remaining_size;
+        *res_postcopy_only += remaining_size;
     } else {
         *res_precopy_only += remaining_size;
     }
-- 
2.39.1

[PULL 4/5] migration: Remove unused res_compatible

[Juan Quintela]

Nothing assigns to it after previous commit.

Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Signed-off-by: Juan Quintela <quintela@redhat.com>
---
 include/migration/register.h   |  7 ++-----
 migration/savevm.h             |  2 --
 hw/s390x/s390-stattrib.c       |  1 -
 hw/vfio/migration.c            |  3 +--
 migration/block-dirty-bitmap.c |  1 -
 migration/block.c              |  1 -
 migration/migration.c          | 18 ++++++++----------
 migration/ram.c                |  2 --
 migration/savevm.c             |  8 ++------
 hw/vfio/trace-events           |  2 +-
 migration/trace-events         |  4 ++--
 11 files changed, 16 insertions(+), 33 deletions(-)

diff --git a/include/migration/register.h b/include/migration/register.h
index b91a0cdbf8..a958a92a0f 100644
--- a/include/migration/register.h
+++ b/include/migration/register.h
@@ -49,22 +49,19 @@ typedef struct SaveVMHandlers {
     /* Note for save_live_pending:
      * - res_precopy_only is for data which must be migrated in precopy phase
      *     or in stopped state, in other words - before target vm start
-     * - res_compatible is for data which may be migrated in any phase
      * - res_postcopy_only is for data which must be migrated in postcopy phase
      *     or in stopped state, in other words - after source vm stop
      *
-     * Sum of res_postcopy_only, res_compatible and res_postcopy_only is the
-     * whole amount of pending data.
+     * Sum of res_postcopy_only and res_postcopy_only is the whole
+     * amount of pending data.
      */
     /* This estimates the remaining data to transfer */
     void (*state_pending_estimate)(void *opaque,
                                    uint64_t *res_precopy_only,
-                                   uint64_t *res_compatible,
                                    uint64_t *res_postcopy_only);
     /* This calculate the exact remaining data to transfer */
     void (*state_pending_exact)(void *opaque,
                                 uint64_t *res_precopy_only,
-                                uint64_t *res_compatible,
                                 uint64_t *res_postcopy_only);
     LoadStateHandler *load_state;
     int (*load_setup)(QEMUFile *f, void *opaque);
diff --git a/migration/savevm.h b/migration/savevm.h
index b1901e68d5..bd625a644b 100644
--- a/migration/savevm.h
+++ b/migration/savevm.h
@@ -41,10 +41,8 @@ void qemu_savevm_state_complete_postcopy(QEMUFile *f);
 int qemu_savevm_state_complete_precopy(QEMUFile *f, bool iterable_only,
                                        bool inactivate_disks);
 void qemu_savevm_state_pending_exact(uint64_t *res_precopy_only,
-                                     uint64_t *res_compatible,
                                      uint64_t *res_postcopy_only);
 void qemu_savevm_state_pending_estimate(uint64_t *res_precopy_only,
-                                        uint64_t *res_compatible,
                                         uint64_t *res_postcopy_only);
 void qemu_savevm_send_ping(QEMUFile *f, uint32_t value);
 void qemu_savevm_send_open_return_path(QEMUFile *f);
diff --git a/hw/s390x/s390-stattrib.c b/hw/s390x/s390-stattrib.c
index 3e32002eab..c7ae9184ab 100644
--- a/hw/s390x/s390-stattrib.c
+++ b/hw/s390x/s390-stattrib.c
@@ -184,7 +184,6 @@ static int cmma_save_setup(QEMUFile *f, void *opaque)
 
 static void cmma_state_pending(void *opaque,
                                uint64_t *res_precopy_only,
-                               uint64_t *res_compatible,
                                uint64_t *res_postcopy_only)
 {
     S390StAttribState *sas = S390_STATTRIB(opaque);
diff --git a/hw/vfio/migration.c b/hw/vfio/migration.c
index b3318f0f20..fb0dd9571d 100644
--- a/hw/vfio/migration.c
+++ b/hw/vfio/migration.c
@@ -458,7 +458,6 @@ static void vfio_save_cleanup(void *opaque)
 
 static void vfio_state_pending(void *opaque,
                                uint64_t *res_precopy_only,
-                               uint64_t *res_compatible,
                                uint64_t *res_postcopy_only)
 {
     VFIODevice *vbasedev = opaque;
@@ -473,7 +472,7 @@ static void vfio_state_pending(void *opaque,
     *res_precopy_only += migration->pending_bytes;
 
     trace_vfio_state_pending(vbasedev->name, *res_precopy_only,
-                            *res_postcopy_only, *res_compatible);
+                            *res_postcopy_only);
 }
 
 static int vfio_save_iterate(QEMUFile *f, void *opaque)
diff --git a/migration/block-dirty-bitmap.c b/migration/block-dirty-bitmap.c
index 5a621419d3..9c6655e11a 100644
--- a/migration/block-dirty-bitmap.c
+++ b/migration/block-dirty-bitmap.c
@@ -764,7 +764,6 @@ static int dirty_bitmap_save_complete(QEMUFile *f, void *opaque)
 
 static void dirty_bitmap_state_pending(void *opaque,
                                        uint64_t *res_precopy_only,
-                                       uint64_t *res_compatible,
                                        uint64_t *res_postcopy_only)
 {
     DBMSaveState *s = &((DBMState *)opaque)->save;
diff --git a/migration/block.c b/migration/block.c
index b5ce506d01..168ef89a82 100644
--- a/migration/block.c
+++ b/migration/block.c
@@ -855,7 +855,6 @@ static int block_save_complete(QEMUFile *f, void *opaque)
 
 static void block_state_pending(void *opaque,
                                 uint64_t *res_precopy_only,
-                                uint64_t *res_compatible,
                                 uint64_t *res_postcopy_only)
 {
     /* Estimate pending number of bytes to send */
diff --git a/migration/migration.c b/migration/migration.c
index 90fca70cb7..296f7fe768 100644
--- a/migration/migration.c
+++ b/migration/migration.c
@@ -3863,20 +3863,18 @@ typedef enum {
  */
 static MigIterateState migration_iteration_run(MigrationState *s)
 {
-    uint64_t pend_pre, pend_compat, pend_post;
+    uint64_t pend_pre, pend_post;
     bool in_postcopy = s->state == MIGRATION_STATUS_POSTCOPY_ACTIVE;
 
-    qemu_savevm_state_pending_estimate(&pend_pre, &pend_compat, &pend_post);
-    uint64_t pending_size = pend_pre + pend_compat + pend_post;
+    qemu_savevm_state_pending_estimate(&pend_pre, &pend_post);
+    uint64_t pending_size = pend_pre + pend_post;
 
-    trace_migrate_pending_estimate(pending_size,
-                                   pend_pre, pend_compat, pend_post);
+    trace_migrate_pending_estimate(pending_size, pend_pre, pend_post);
 
-    if (pend_pre + pend_compat <= s->threshold_size) {
-        qemu_savevm_state_pending_exact(&pend_pre, &pend_compat, &pend_post);
-        pending_size = pend_pre + pend_compat + pend_post;
-        trace_migrate_pending_exact(pending_size,
-                                    pend_pre, pend_compat, pend_post);
+    if (pend_pre <= s->threshold_size) {
+        qemu_savevm_state_pending_exact(&pend_pre, &pend_post);
+        pending_size = pend_pre + pend_post;
+        trace_migrate_pending_exact(pending_size, pend_pre, pend_post);
     }
 
     if (!pending_size || pending_size < s->threshold_size) {
diff --git a/migration/ram.c b/migration/ram.c
index ecf697a58d..178f92a77f 100644
--- a/migration/ram.c
+++ b/migration/ram.c
@@ -3491,7 +3491,6 @@ static int ram_save_complete(QEMUFile *f, void *opaque)
 
 static void ram_state_pending_estimate(void *opaque,
                                        uint64_t *res_precopy_only,
-                                       uint64_t *res_compatible,
                                        uint64_t *res_postcopy_only)
 {
     RAMState **temp = opaque;
@@ -3509,7 +3508,6 @@ static void ram_state_pending_estimate(void *opaque,
 
 static void ram_state_pending_exact(void *opaque,
                                     uint64_t *res_precopy_only,
-                                    uint64_t *res_compatible,
                                     uint64_t *res_postcopy_only)
 {
     RAMState **temp = opaque;
diff --git a/migration/savevm.c b/migration/savevm.c
index b5e6962bb6..80b7f1222a 100644
--- a/migration/savevm.c
+++ b/migration/savevm.c
@@ -1542,13 +1542,11 @@ flush:
  * for units that can't do postcopy.
  */
 void qemu_savevm_state_pending_estimate(uint64_t *res_precopy_only,
-                                        uint64_t *res_compatible,
                                         uint64_t *res_postcopy_only)
 {
     SaveStateEntry *se;
 
     *res_precopy_only = 0;
-    *res_compatible = 0;
     *res_postcopy_only = 0;
 
     QTAILQ_FOREACH(se, &savevm_state.handlers, entry) {
@@ -1561,19 +1559,17 @@ void qemu_savevm_state_pending_estimate(uint64_t *res_precopy_only,
             }
         }
         se->ops->state_pending_estimate(se->opaque,
-                                        res_precopy_only, res_compatible,
+                                        res_precopy_only,
                                         res_postcopy_only);
     }
 }
 
 void qemu_savevm_state_pending_exact(uint64_t *res_precopy_only,
-                                     uint64_t *res_compatible,
                                      uint64_t *res_postcopy_only)
 {
     SaveStateEntry *se;
 
     *res_precopy_only = 0;
-    *res_compatible = 0;
     *res_postcopy_only = 0;
 
     QTAILQ_FOREACH(se, &savevm_state.handlers, entry) {
@@ -1586,7 +1582,7 @@ void qemu_savevm_state_pending_exact(uint64_t *res_precopy_only,
             }
         }
         se->ops->state_pending_exact(se->opaque,
-                                     res_precopy_only, res_compatible,
+                                     res_precopy_only,
                                      res_postcopy_only);
     }
 }
diff --git a/hw/vfio/trace-events b/hw/vfio/trace-events
index 52de1c84f8..90a8aecb37 100644
--- a/hw/vfio/trace-events
+++ b/hw/vfio/trace-events
@@ -157,7 +157,7 @@ vfio_save_cleanup(const char *name) " (%s)"
 vfio_save_buffer(const char *name, uint64_t data_offset, uint64_t data_size, uint64_t pending) " (%s) Offset 0x%"PRIx64" size 0x%"PRIx64" pending 0x%"PRIx64
 vfio_update_pending(const char *name, uint64_t pending) " (%s) pending 0x%"PRIx64
 vfio_save_device_config_state(const char *name) " (%s)"
-vfio_state_pending(const char *name, uint64_t precopy, uint64_t postcopy, uint64_t compatible) " (%s) precopy 0x%"PRIx64" postcopy 0x%"PRIx64" compatible 0x%"PRIx64
+vfio_state_pending(const char *name, uint64_t precopy, uint64_t postcopy) " (%s) precopy 0x%"PRIx64" postcopy 0x%"PRIx64
 vfio_save_iterate(const char *name, int data_size) " (%s) data_size %d"
 vfio_save_complete_precopy(const char *name) " (%s)"
 vfio_load_device_config_state(const char *name) " (%s)"
diff --git a/migration/trace-events b/migration/trace-events
index b20e1271bc..92161eeac5 100644
--- a/migration/trace-events
+++ b/migration/trace-events
@@ -150,8 +150,8 @@ migrate_fd_cleanup(void) ""
 migrate_fd_error(const char *error_desc) "error=%s"
 migrate_fd_cancel(void) ""
 migrate_handle_rp_req_pages(const char *rbname, size_t start, size_t len) "in %s at 0x%zx len 0x%zx"
-migrate_pending_exact(uint64_t size, uint64_t pre, uint64_t compat, uint64_t post) "exact pending size %" PRIu64 " (pre = %" PRIu64 " compat=%" PRIu64 " post=%" PRIu64 ")"
-migrate_pending_estimate(uint64_t size, uint64_t pre, uint64_t compat, uint64_t post) "estimate pending size %" PRIu64 " (pre = %" PRIu64 " compat=%" PRIu64 " post=%" PRIu64 ")"
+migrate_pending_exact(uint64_t size, uint64_t pre, uint64_t post) "exact pending size %" PRIu64 " (pre = %" PRIu64 " post=%" PRIu64 ")"
+migrate_pending_estimate(uint64_t size, uint64_t pre, uint64_t post) "estimate pending size %" PRIu64 " (pre = %" PRIu64 " post=%" PRIu64 ")"
 migrate_send_rp_message(int msg_type, uint16_t len) "%d: len %d"
 migrate_send_rp_recv_bitmap(char *name, int64_t size) "block '%s' size 0x%"PRIi64
 migration_completion_file_err(void) ""
-- 
2.39.1

[PULL 5/5] migration: Rename res_{postcopy,precopy}_only

[Juan Quintela]

Once that res_compatible is removed, they don't make sense anymore.
We remove the _only preffix.  And to make things clearer we rename
them to must_precopy and can_postcopy.

Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Signed-off-by: Juan Quintela <quintela@redhat.com>
---
 include/migration/register.h   | 27 +++++++++++++++------------
 migration/savevm.h             |  8 ++++----
 hw/s390x/s390-stattrib.c       |  7 +++----
 hw/vfio/migration.c            | 10 ++++------
 migration/block-dirty-bitmap.c |  6 +++---
 migration/block.c              |  7 +++----
 migration/migration.c          | 18 +++++++++---------
 migration/ram.c                | 18 ++++++++----------
 migration/savevm.c             | 24 ++++++++++--------------
 9 files changed, 59 insertions(+), 66 deletions(-)

diff --git a/include/migration/register.h b/include/migration/register.h
index a958a92a0f..a8dfd8fefd 100644
--- a/include/migration/register.h
+++ b/include/migration/register.h
@@ -47,22 +47,25 @@ typedef struct SaveVMHandlers {
     /* This runs outside the iothread lock!  */
     int (*save_setup)(QEMUFile *f, void *opaque);
     /* Note for save_live_pending:
-     * - res_precopy_only is for data which must be migrated in precopy phase
-     *     or in stopped state, in other words - before target vm start
-     * - res_postcopy_only is for data which must be migrated in postcopy phase
-     *     or in stopped state, in other words - after source vm stop
+     * must_precopy:
+     * - must be migrated in precopy or in stopped state
+     * - i.e. must be migrated before target start
      *
-     * Sum of res_postcopy_only and res_postcopy_only is the whole
-     * amount of pending data.
+     * can_postcopy:
+     * - can migrate in postcopy or in stopped state
+     * - i.e. can migrate after target start
+     * - some can also be migrated during precopy (RAM)
+     * - some must be migrated after source stops (block-dirty-bitmap)
+     *
+     * Sum of can_postcopy and must_postcopy is the whole amount of
+     * pending data.
      */
     /* This estimates the remaining data to transfer */
-    void (*state_pending_estimate)(void *opaque,
-                                   uint64_t *res_precopy_only,
-                                   uint64_t *res_postcopy_only);
+    void (*state_pending_estimate)(void *opaque, uint64_t *must_precopy,
+                                   uint64_t *can_postcopy);
     /* This calculate the exact remaining data to transfer */
-    void (*state_pending_exact)(void *opaque,
-                                uint64_t *res_precopy_only,
-                                uint64_t *res_postcopy_only);
+    void (*state_pending_exact)(void *opaque, uint64_t *must_precopy,
+                                uint64_t *can_postcopy);
     LoadStateHandler *load_state;
     int (*load_setup)(QEMUFile *f, void *opaque);
     int (*load_cleanup)(void *opaque);
diff --git a/migration/savevm.h b/migration/savevm.h
index bd625a644b..fb636735f0 100644
--- a/migration/savevm.h
+++ b/migration/savevm.h
@@ -40,10 +40,10 @@ void qemu_savevm_state_cleanup(void);
 void qemu_savevm_state_complete_postcopy(QEMUFile *f);
 int qemu_savevm_state_complete_precopy(QEMUFile *f, bool iterable_only,
                                        bool inactivate_disks);
-void qemu_savevm_state_pending_exact(uint64_t *res_precopy_only,
-                                     uint64_t *res_postcopy_only);
-void qemu_savevm_state_pending_estimate(uint64_t *res_precopy_only,
-                                        uint64_t *res_postcopy_only);
+void qemu_savevm_state_pending_exact(uint64_t *must_precopy,
+                                     uint64_t *can_postcopy);
+void qemu_savevm_state_pending_estimate(uint64_t *must_precopy,
+                                        uint64_t *can_postcopy);
 void qemu_savevm_send_ping(QEMUFile *f, uint32_t value);
 void qemu_savevm_send_open_return_path(QEMUFile *f);
 int qemu_savevm_send_packaged(QEMUFile *f, const uint8_t *buf, size_t len);
diff --git a/hw/s390x/s390-stattrib.c b/hw/s390x/s390-stattrib.c
index c7ae9184ab..aed919ad7d 100644
--- a/hw/s390x/s390-stattrib.c
+++ b/hw/s390x/s390-stattrib.c
@@ -182,16 +182,15 @@ static int cmma_save_setup(QEMUFile *f, void *opaque)
     return 0;
 }
 
-static void cmma_state_pending(void *opaque,
-                               uint64_t *res_precopy_only,
-                               uint64_t *res_postcopy_only)
+static void cmma_state_pending(void *opaque, uint64_t *must_precopy,
+                               uint64_t *can_postcopy)
 {
     S390StAttribState *sas = S390_STATTRIB(opaque);
     S390StAttribClass *sac = S390_STATTRIB_GET_CLASS(sas);
     long long res = sac->get_dirtycount(sas);
 
     if (res >= 0) {
-        *res_precopy_only += res;
+        *must_precopy += res;
     }
 }
 
diff --git a/hw/vfio/migration.c b/hw/vfio/migration.c
index fb0dd9571d..83d2d44080 100644
--- a/hw/vfio/migration.c
+++ b/hw/vfio/migration.c
@@ -456,9 +456,8 @@ static void vfio_save_cleanup(void *opaque)
     trace_vfio_save_cleanup(vbasedev->name);
 }
 
-static void vfio_state_pending(void *opaque,
-                               uint64_t *res_precopy_only,
-                               uint64_t *res_postcopy_only)
+static void vfio_state_pending(void *opaque, uint64_t *must_precopy,
+                               uint64_t *can_postcopy)
 {
     VFIODevice *vbasedev = opaque;
     VFIOMigration *migration = vbasedev->migration;
@@ -469,10 +468,9 @@ static void vfio_state_pending(void *opaque,
         return;
     }
 
-    *res_precopy_only += migration->pending_bytes;
+    *must_precopy += migration->pending_bytes;
 
-    trace_vfio_state_pending(vbasedev->name, *res_precopy_only,
-                            *res_postcopy_only);
+    trace_vfio_state_pending(vbasedev->name, *must_precopy, *can_postcopy);
 }
 
 static int vfio_save_iterate(QEMUFile *f, void *opaque)
diff --git a/migration/block-dirty-bitmap.c b/migration/block-dirty-bitmap.c
index 9c6655e11a..fe73aa94b1 100644
--- a/migration/block-dirty-bitmap.c
+++ b/migration/block-dirty-bitmap.c
@@ -763,8 +763,8 @@ static int dirty_bitmap_save_complete(QEMUFile *f, void *opaque)
 }
 
 static void dirty_bitmap_state_pending(void *opaque,
-                                       uint64_t *res_precopy_only,
-                                       uint64_t *res_postcopy_only)
+                                       uint64_t *must_precopy,
+                                       uint64_t *can_postcopy)
 {
     DBMSaveState *s = &((DBMState *)opaque)->save;
     SaveBitmapState *dbms;
@@ -784,7 +784,7 @@ static void dirty_bitmap_state_pending(void *opaque,
 
     trace_dirty_bitmap_state_pending(pending);
 
-    *res_postcopy_only += pending;
+    *can_postcopy += pending;
 }
 
 /* First occurrence of this bitmap. It should be created if doesn't exist */
diff --git a/migration/block.c b/migration/block.c
index 168ef89a82..426a25bb19 100644
--- a/migration/block.c
+++ b/migration/block.c
@@ -853,9 +853,8 @@ static int block_save_complete(QEMUFile *f, void *opaque)
     return 0;
 }
 
-static void block_state_pending(void *opaque,
-                                uint64_t *res_precopy_only,
-                                uint64_t *res_postcopy_only)
+static void block_state_pending(void *opaque, uint64_t *must_precopy,
+                                uint64_t *can_postcopy)
 {
     /* Estimate pending number of bytes to send */
     uint64_t pending;
@@ -876,7 +875,7 @@ static void block_state_pending(void *opaque,
 
     trace_migration_block_state_pending(pending);
     /* We don't do postcopy */
-    *res_precopy_only += pending;
+    *must_precopy += pending;
 }
 
 static int block_load(QEMUFile *f, void *opaque, int version_id)
diff --git a/migration/migration.c b/migration/migration.c
index 296f7fe768..ae2025d9d8 100644
--- a/migration/migration.c
+++ b/migration/migration.c
@@ -3863,18 +3863,18 @@ typedef enum {
  */
 static MigIterateState migration_iteration_run(MigrationState *s)
 {
-    uint64_t pend_pre, pend_post;
+    uint64_t must_precopy, can_postcopy;
     bool in_postcopy = s->state == MIGRATION_STATUS_POSTCOPY_ACTIVE;
 
-    qemu_savevm_state_pending_estimate(&pend_pre, &pend_post);
-    uint64_t pending_size = pend_pre + pend_post;
+    qemu_savevm_state_pending_estimate(&must_precopy, &can_postcopy);
+    uint64_t pending_size = must_precopy + can_postcopy;
 
-    trace_migrate_pending_estimate(pending_size, pend_pre, pend_post);
+    trace_migrate_pending_estimate(pending_size, must_precopy, can_postcopy);
 
-    if (pend_pre <= s->threshold_size) {
-        qemu_savevm_state_pending_exact(&pend_pre, &pend_post);
-        pending_size = pend_pre + pend_post;
-        trace_migrate_pending_exact(pending_size, pend_pre, pend_post);
+    if (must_precopy <= s->threshold_size) {
+        qemu_savevm_state_pending_exact(&must_precopy, &can_postcopy);
+        pending_size = must_precopy + can_postcopy;
+        trace_migrate_pending_exact(pending_size, must_precopy, can_postcopy);
     }
 
     if (!pending_size || pending_size < s->threshold_size) {
@@ -3884,7 +3884,7 @@ static MigIterateState migration_iteration_run(MigrationState *s)
     }
 
     /* Still a significant amount to transfer */
-    if (!in_postcopy && pend_pre <= s->threshold_size &&
+    if (!in_postcopy && must_precopy <= s->threshold_size &&
         qatomic_read(&s->start_postcopy)) {
         if (postcopy_start(s)) {
             error_report("%s: postcopy failed to start", __func__);
diff --git a/migration/ram.c b/migration/ram.c
index 178f92a77f..96e8a19a58 100644
--- a/migration/ram.c
+++ b/migration/ram.c
@@ -3489,9 +3489,8 @@ static int ram_save_complete(QEMUFile *f, void *opaque)
     return 0;
 }
 
-static void ram_state_pending_estimate(void *opaque,
-                                       uint64_t *res_precopy_only,
-                                       uint64_t *res_postcopy_only)
+static void ram_state_pending_estimate(void *opaque, uint64_t *must_precopy,
+                                       uint64_t *can_postcopy)
 {
     RAMState **temp = opaque;
     RAMState *rs = *temp;
@@ -3500,15 +3499,14 @@ static void ram_state_pending_estimate(void *opaque,
 
     if (migrate_postcopy_ram()) {
         /* We can do postcopy, and all the data is postcopiable */
-        *res_postcopy_only += remaining_size;
+        *can_postcopy += remaining_size;
     } else {
-        *res_precopy_only += remaining_size;
+        *must_precopy += remaining_size;
     }
 }
 
-static void ram_state_pending_exact(void *opaque,
-                                    uint64_t *res_precopy_only,
-                                    uint64_t *res_postcopy_only)
+static void ram_state_pending_exact(void *opaque, uint64_t *must_precopy,
+                                    uint64_t *can_postcopy)
 {
     RAMState **temp = opaque;
     RAMState *rs = *temp;
@@ -3526,9 +3524,9 @@ static void ram_state_pending_exact(void *opaque,
 
     if (migrate_postcopy_ram()) {
         /* We can do postcopy, and all the data is postcopiable */
-        *res_postcopy_only += remaining_size;
+        *can_postcopy += remaining_size;
     } else {
-        *res_precopy_only += remaining_size;
+        *must_precopy += remaining_size;
     }
 }
 
diff --git a/migration/savevm.c b/migration/savevm.c
index 80b7f1222a..aa54a67fda 100644
--- a/migration/savevm.c
+++ b/migration/savevm.c
@@ -1541,13 +1541,13 @@ flush:
  * the result is split into the amount for units that can and
  * for units that can't do postcopy.
  */
-void qemu_savevm_state_pending_estimate(uint64_t *res_precopy_only,
-                                        uint64_t *res_postcopy_only)
+void qemu_savevm_state_pending_estimate(uint64_t *must_precopy,
+                                        uint64_t *can_postcopy)
 {
     SaveStateEntry *se;
 
-    *res_precopy_only = 0;
-    *res_postcopy_only = 0;
+    *must_precopy = 0;
+    *can_postcopy = 0;
 
     QTAILQ_FOREACH(se, &savevm_state.handlers, entry) {
         if (!se->ops || !se->ops->state_pending_estimate) {
@@ -1558,19 +1558,17 @@ void qemu_savevm_state_pending_estimate(uint64_t *res_precopy_only,
                 continue;
             }
         }
-        se->ops->state_pending_estimate(se->opaque,
-                                        res_precopy_only,
-                                        res_postcopy_only);
+        se->ops->state_pending_estimate(se->opaque, must_precopy, can_postcopy);
     }
 }
 
-void qemu_savevm_state_pending_exact(uint64_t *res_precopy_only,
-                                     uint64_t *res_postcopy_only)
+void qemu_savevm_state_pending_exact(uint64_t *must_precopy,
+                                     uint64_t *can_postcopy)
 {
     SaveStateEntry *se;
 
-    *res_precopy_only = 0;
-    *res_postcopy_only = 0;
+    *must_precopy = 0;
+    *can_postcopy = 0;
 
     QTAILQ_FOREACH(se, &savevm_state.handlers, entry) {
         if (!se->ops || !se->ops->state_pending_exact) {
@@ -1581,9 +1579,7 @@ void qemu_savevm_state_pending_exact(uint64_t *res_precopy_only,
                 continue;
             }
         }
-        se->ops->state_pending_exact(se->opaque,
-                                     res_precopy_only,
-                                     res_postcopy_only);
+        se->ops->state_pending_exact(se->opaque, must_precopy, can_postcopy);
     }
 }
 
-- 
2.39.1

Re: [PULL 0/5] Migration 20230215 patches

[Peter Maydell]

On Wed, 15 Feb 2023 at 20:06, Juan Quintela <quintela@redhat.com> wrote:
>
> The following changes since commit 6a50f64ca01d0a7b97f14f069762bfd88160f31e:
>
>   Merge tag 'pull-request-2023-02-14' of https://gitlab.com/thuth/qemu into staging (2023-02-14 14:46:10 +0000)
>
> are available in the Git repository at:
>
>   https://gitlab.com/juan.quintela/qemu.git tags/migration-20230215-pull-request
>
> for you to fetch changes up to 24beea4efe6e6b65fd6248ede936cd3278b2bf8a:
>
>   migration: Rename res_{postcopy,precopy}_only (2023-02-15 20:04:30 +0100)
>
> ----------------------------------------------------------------
> Migration Pull request
>
> This pull request contains:
>
> * Add qemu_file_get_to_fd() a.k.a. make vfio happy(Avihai)
> * migration/block is now DPRINTF() free zone (Philippe)
> * remove res_compat and improve docs (me)
>
> Please apply.


Applied, thanks.

Please update the changelog at https://wiki.qemu.org/ChangeLog/8.0
for any user-visible changes.

-- PMM