[PATCH v4 0/7] Multifd Migration Compression

[PATCH v4 0/7] Multifd Migration Compression

[Juan Quintela]

Based-on: 20200127223321.2742-1-quintela@redhat.com

[v4]
- create new parameters: multifd-zlib-level & multifd-zstd-level
- use proper "conditionals" for qapi (thanks markus)
- more than half of the patches moved to the migration PULL request
  that this series are based on
- method type has moved to one int from a set of flags
- fixed all reviews comments

Please review.

[v3]
- rebased on top of upstream + previous multifd cancel series
- split multifd code into its own file (multifd.[ch])
- split zstd/zlib compression methods (multifd-zstd/zlib.c)
- use qemu module feauture to avoid ifdefs
  (my understanding is that zlib needs to be present, but
  we setup zstd only if it is not there or is disabled)
- multifd-method: none|zlib|zstd

  As far as I can see, there is no easy way to convince qapi that zstd
  option could/couldn't be there depending on compliation flags. I
  ended just checking in migrate_parameters_check() if it is enabled
  and giving an error message otherwise.

Questions:
- I am "reusing" the compress-level parameter for both zstd and zlib,
  but it poses a problem:
  * zlib values: 1-9 (default: 6?)
  * zstd values: 1-19 (default: 3)
So, what should I do:
  * create multifd-zstd-level and multifd-zlib-level (easier)
  * reuse compress-level, and change its maximum values depending on
    multifd-method
  * any other good option?

Please, review.

[v2] - rebase on top of previous arguments posted to the list -
introduces zlib compression - introduces zstd compression

Please help if you know anything about zstd/zlib compression.

This puts compression on top of multifd. Advantages about current
compression:

- We copy all pages in a single packet and then compress the whole
  thing.

- We reuse the compression stream for all the packets sent through the
  same channel.

- We can select nocomp/zlib/zstd levels of compression.

Please, review.

Juan Quintela (7):
  migration: Add support for modules
  multifd: Make no compression operations into its own structure
  multifd: Add multifd-zlib-level parameter
  multifd: Add zlib compression multifd support
  configure: Enable test and libs for zstd
  multifd: Add multifd-zstd-level parameter
  multifd: Add zstd compression multifd support

 configure                    |  30 ++++
 hw/core/qdev-properties.c    |   2 +-
 include/qemu/module.h        |   2 +
 migration/Makefile.objs      |   2 +
 migration/migration.c        |  57 +++++++
 migration/migration.h        |   3 +
 migration/multifd-zlib.c     | 293 +++++++++++++++++++++++++++++++++
 migration/multifd-zstd.c     | 305 +++++++++++++++++++++++++++++++++++
 migration/multifd.c          | 191 +++++++++++++++++++++-
 migration/multifd.h          |  29 ++++
 migration/ram.c              |   2 +-
 monitor/hmp-cmds.c           |   8 +
 qapi/migration.json          |  58 ++++++-
 tests/qtest/migration-test.c |  16 ++
 vl.c                         |   1 +
 15 files changed, 985 insertions(+), 14 deletions(-)
 create mode 100644 migration/multifd-zlib.c
 create mode 100644 migration/multifd-zstd.c

-- 
2.24.1

[PATCH v4 1/7] migration: Add support for modules

[Juan Quintela]

So we don't have to compile everything in, or have ifdefs

Signed-off-by: Juan Quintela <quintela@redhat.com>
---
 include/qemu/module.h | 2 ++
 vl.c                  | 1 +
 2 files changed, 3 insertions(+)

diff --git a/include/qemu/module.h b/include/qemu/module.h
index 65ba596e46..907cb5c0a5 100644
--- a/include/qemu/module.h
+++ b/include/qemu/module.h
@@ -40,6 +40,7 @@ static void __attribute__((constructor)) do_qemu_init_ ## function(void)    \
 #endif
 
 typedef enum {
+    MODULE_INIT_MIGRATION,
     MODULE_INIT_BLOCK,
     MODULE_INIT_OPTS,
     MODULE_INIT_QOM,
@@ -56,6 +57,7 @@ typedef enum {
 #define xen_backend_init(function) module_init(function, \
                                                MODULE_INIT_XEN_BACKEND)
 #define libqos_init(function) module_init(function, MODULE_INIT_LIBQOS)
+#define migration_init(function) module_init(function, MODULE_INIT_MIGRATION)
 
 #define block_module_load_one(lib) module_load_one("block-", lib)
 #define ui_module_load_one(lib) module_load_one("ui-", lib)
diff --git a/vl.c b/vl.c
index b0f52c4d6e..9f8577955a 100644
--- a/vl.c
+++ b/vl.c
@@ -2890,6 +2890,7 @@ int main(int argc, char **argv, char **envp)
     qemu_init_exec_dir(argv[0]);
 
     module_call_init(MODULE_INIT_QOM);
+    module_call_init(MODULE_INIT_MIGRATION);
 
     qemu_add_opts(&qemu_drive_opts);
     qemu_add_drive_opts(&qemu_legacy_drive_opts);
-- 
2.24.1

[PATCH v4 2/7] multifd: Make no compression operations into its own structure

[Juan Quintela]

It will be used later.

Signed-off-by: Juan Quintela <quintela@redhat.com>

---
Move setup of ->ops helper to proper place (wei)
Rename s/none/nocomp/ (dave)
Introduce MULTIFD_FLAG_NOCOMP
right order of arguments for print
Introduce MULTIFD_FLAG_METHOD_MASK (now it is a 4 bit value)
---
 migration/migration.c |   9 ++
 migration/migration.h |   1 +
 migration/multifd.c   | 185 ++++++++++++++++++++++++++++++++++++++++--
 migration/multifd.h   |  25 ++++++
 migration/ram.c       |   1 +
 5 files changed, 213 insertions(+), 8 deletions(-)

diff --git a/migration/migration.c b/migration/migration.c
index cd72bb6e9a..06f6c2d529 100644
--- a/migration/migration.c
+++ b/migration/migration.c
@@ -2245,6 +2245,15 @@ int migrate_multifd_channels(void)
     return s->parameters.multifd_channels;
 }
 
+MultiFDMethod migrate_multifd_method(void)
+{
+    MigrationState *s;
+
+    s = migrate_get_current();
+
+    return s->parameters.multifd_method;
+}
+
 int migrate_use_xbzrle(void)
 {
     MigrationState *s;
diff --git a/migration/migration.h b/migration/migration.h
index 8473ddfc88..3d23a0852e 100644
--- a/migration/migration.h
+++ b/migration/migration.h
@@ -300,6 +300,7 @@ bool migrate_auto_converge(void);
 bool migrate_use_multifd(void);
 bool migrate_pause_before_switchover(void);
 int migrate_multifd_channels(void);
+MultiFDMethod migrate_multifd_method(void);
 
 int migrate_use_xbzrle(void);
 int64_t migrate_xbzrle_cache_size(void);
diff --git a/migration/multifd.c b/migration/multifd.c
index b3e8ae9bcc..1c49c2a665 100644
--- a/migration/multifd.c
+++ b/migration/multifd.c
@@ -38,6 +38,134 @@ typedef struct {
     uint64_t unused2[4];    /* Reserved for future use */
 } __attribute__((packed)) MultiFDInit_t;
 
+/* Multifd without compression */
+
+/**
+ * nocomp_send_setup: setup send side
+ *
+ * For no compression this function does nothing.
+ *
+ * Returns 0 for success or -1 for error
+ *
+ * @p: Params for the channel that we are using
+ * @errp: pointer to an error
+ */
+static int nocomp_send_setup(MultiFDSendParams *p, Error **errp)
+{
+    return 0;
+}
+
+/**
+ * nocomp_send_cleanup: cleanup send side
+ *
+ * For no compression this function does nothing.
+ *
+ * @p: Params for the channel that we are using
+ */
+static void nocomp_send_cleanup(MultiFDSendParams *p, Error **errp)
+{
+    return;
+}
+
+/**
+ * nocomp_send_prepare: prepare date to be able to send
+ *
+ * For no compression we just have to calculate the size of the
+ * packet.
+ *
+ * Returns 0 for success or -1 for error
+ *
+ * @p: Params for the channel that we are using
+ * @used: number of pages used
+ * @errp: pointer to an error
+ */
+static int nocomp_send_prepare(MultiFDSendParams *p, uint32_t used,
+                               Error **errp)
+{
+    p->next_packet_size = used * qemu_target_page_size();
+    p->flags |= MULTIFD_FLAG_NOCOMP;
+    return 0;
+}
+
+/**
+ * nocomp_send_write: do the actual write of the data
+ *
+ * For no compression we just have to write the data.
+ *
+ * Returns 0 for success or -1 for error
+ *
+ * @p: Params for the channel that we are using
+ * @used: number of pages used
+ * @errp: pointer to an error
+ */
+static int nocomp_send_write(MultiFDSendParams *p, uint32_t used, Error **errp)
+{
+    return qio_channel_writev_all(p->c, p->pages->iov, used, errp);
+}
+
+/**
+ * nocomp_recv_setup: setup receive side
+ *
+ * For no compression this function does nothing.
+ *
+ * Returns 0 for success or -1 for error
+ *
+ * @p: Params for the channel that we are using
+ * @errp: pointer to an error
+ */
+static int nocomp_recv_setup(MultiFDRecvParams *p, Error **errp)
+{
+    return 0;
+}
+
+/**
+ * nocomp_recv_cleanup: setup receive side
+ *
+ * For no compression this function does nothing.
+ *
+ * @p: Params for the channel that we are using
+ */
+static void nocomp_recv_cleanup(MultiFDRecvParams *p)
+{
+}
+
+/**
+ * nocomp_recv_pages: read the data from the channel into actual pages
+ *
+ * For no compression we just need to read things into the correct place.
+ *
+ * Returns 0 for success or -1 for error
+ *
+ * @p: Params for the channel that we are using
+ * @used: number of pages used
+ * @errp: pointer to an error
+ */
+static int nocomp_recv_pages(MultiFDRecvParams *p, uint32_t used, Error **errp)
+{
+    uint32_t flags = p->flags & MULTIFD_FLAG_METHOD_MASK;
+
+    if (flags != MULTIFD_FLAG_NOCOMP) {
+        error_setg(errp, "multifd %d: flags received %x flags expected %x",
+                   p->id, flags, MULTIFD_FLAG_NOCOMP);
+        return -1;
+    }
+    return qio_channel_readv_all(p->c, p->pages->iov, used, errp);
+}
+
+static MultiFDMethods multifd_nocomp_ops = {
+    .send_setup = nocomp_send_setup,
+    .send_cleanup = nocomp_send_cleanup,
+    .send_prepare = nocomp_send_prepare,
+    .send_write = nocomp_send_write,
+    .recv_setup = nocomp_recv_setup,
+    .recv_cleanup = nocomp_recv_cleanup,
+    .recv_pages = nocomp_recv_pages
+};
+
+static MultiFDMethods *multifd_ops[MULTIFD_METHOD__MAX] = {
+    [MULTIFD_METHOD_NONE] = &multifd_nocomp_ops,
+};
+
 static int multifd_send_initial_packet(MultiFDSendParams *p, Error **errp)
 {
     MultiFDInit_t msg = {};
@@ -246,6 +374,8 @@ struct {
      * We will use atomic operations.  Only valid values are 0 and 1.
      */
     int exiting;
+    /* multifd ops */
+    MultiFDMethods *ops;
 } *multifd_send_state;
 
 /*
@@ -397,6 +527,7 @@ void multifd_save_cleanup(void)
     }
     for (i = 0; i < migrate_multifd_channels(); i++) {
         MultiFDSendParams *p = &multifd_send_state->params[i];
+        Error *local_err = NULL;
 
         socket_send_channel_destroy(p->c);
         p->c = NULL;
@@ -410,6 +541,10 @@ void multifd_save_cleanup(void)
         p->packet_len = 0;
         g_free(p->packet);
         p->packet = NULL;
+        multifd_send_state->ops->send_cleanup(p, &local_err);
+        if (local_err) {
+            migrate_set_error(migrate_get_current(), local_err);
+        }
     }
     qemu_sem_destroy(&multifd_send_state->channels_ready);
     g_free(multifd_send_state->params);
@@ -494,7 +629,14 @@ static void *multifd_send_thread(void *opaque)
             uint64_t packet_num = p->packet_num;
             flags = p->flags;
 
-            p->next_packet_size = used * qemu_target_page_size();
+            if (used) {
+                ret = multifd_send_state->ops->send_prepare(p, used,
+                                                            &local_err);
+                if (ret != 0) {
+                    qemu_mutex_unlock(&p->mutex);
+                    break;
+                }
+            }
             multifd_send_fill_packet(p);
             p->flags = 0;
             p->num_packets++;
@@ -513,8 +655,7 @@ static void *multifd_send_thread(void *opaque)
             }
 
             if (used) {
-                ret = qio_channel_writev_all(p->c, p->pages->iov,
-                                             used, &local_err);
+                ret = multifd_send_state->ops->send_write(p, used, &local_err);
                 if (ret != 0) {
                     break;
                 }
@@ -604,6 +745,7 @@ int multifd_save_setup(Error **errp)
     multifd_send_state->pages = multifd_pages_init(page_count);
     qemu_sem_init(&multifd_send_state->channels_ready, 0);
     atomic_set(&multifd_send_state->exiting, 0);
+    multifd_send_state->ops = multifd_ops[migrate_multifd_method()];
 
     for (i = 0; i < thread_count; i++) {
         MultiFDSendParams *p = &multifd_send_state->params[i];
@@ -623,6 +765,18 @@ int multifd_save_setup(Error **errp)
         p->name = g_strdup_printf("multifdsend_%d", i);
         socket_send_channel_create(multifd_new_send_channel_async, p);
     }
+
+    for (i = 0; i < thread_count; i++) {
+        MultiFDSendParams *p = &multifd_send_state->params[i];
+        Error *local_err = NULL;
+        int ret;
+
+        ret = multifd_send_state->ops->send_setup(p, &local_err);
+        if (ret) {
+            error_propagate(errp, local_err);
+            return ret;
+        }
+    }
     return 0;
 }
 
@@ -634,6 +788,8 @@ struct {
     QemuSemaphore sem_sync;
     /* global number of generated multifd packets */
     uint64_t packet_num;
+    /* multifd ops */
+    MultiFDMethods *ops;
 } *multifd_recv_state;
 
 static void multifd_recv_terminate_threads(Error *err)
@@ -673,7 +829,6 @@ static void multifd_recv_terminate_threads(Error *err)
 int multifd_load_cleanup(Error **errp)
 {
     int i;
-    int ret = 0;
 
     if (!migrate_use_multifd()) {
         return 0;
@@ -706,6 +861,7 @@ int multifd_load_cleanup(Error **errp)
         p->packet_len = 0;
         g_free(p->packet);
         p->packet = NULL;
+        multifd_recv_state->ops->recv_cleanup(p);
     }
     qemu_sem_destroy(&multifd_recv_state->sem_sync);
     g_free(multifd_recv_state->params);
@@ -713,7 +869,7 @@ int multifd_load_cleanup(Error **errp)
     g_free(multifd_recv_state);
     multifd_recv_state = NULL;
 
-    return ret;
+    return 0;
 }
 
 void multifd_recv_sync_main(void)
@@ -778,6 +934,8 @@ static void *multifd_recv_thread(void *opaque)
 
         used = p->pages->used;
         flags = p->flags;
+        /* recv methods don't know how to handle the SYNC flag */
+        p->flags &= ~MULTIFD_FLAG_SYNC;
         trace_multifd_recv(p->id, p->packet_num, used, flags,
                            p->next_packet_size);
         p->num_packets++;
@@ -785,8 +943,7 @@ static void *multifd_recv_thread(void *opaque)
         qemu_mutex_unlock(&p->mutex);
 
         if (used) {
-            ret = qio_channel_readv_all(p->c, p->pages->iov,
-                                        used, &local_err);
+            ret = multifd_recv_state->ops->recv_pages(p, used, &local_err);
             if (ret != 0) {
                 break;
             }
@@ -825,6 +982,7 @@ int multifd_load_setup(Error **errp)
     multifd_recv_state->params = g_new0(MultiFDRecvParams, thread_count);
     atomic_set(&multifd_recv_state->count, 0);
     qemu_sem_init(&multifd_recv_state->sem_sync, 0);
+    multifd_recv_state->ops = multifd_ops[migrate_multifd_method()];
 
     for (i = 0; i < thread_count; i++) {
         MultiFDRecvParams *p = &multifd_recv_state->params[i];
@@ -839,6 +997,18 @@ int multifd_load_setup(Error **errp)
         p->packet = g_malloc0(p->packet_len);
         p->name = g_strdup_printf("multifdrecv_%d", i);
     }
+
+    for (i = 0; i < thread_count; i++) {
+        MultiFDRecvParams *p = &multifd_recv_state->params[i];
+        Error *local_err = NULL;
+        int ret;
+
+        ret = multifd_recv_state->ops->recv_setup(p, &local_err);
+        if (ret) {
+            error_propagate(errp, local_err);
+            return ret;
+        }
+    }
     return 0;
 }
 
@@ -896,4 +1066,3 @@ bool multifd_recv_new_channel(QIOChannel *ioc, Error **errp)
     return atomic_read(&multifd_recv_state->count) ==
            migrate_multifd_channels();
 }
-
diff --git a/migration/multifd.h b/migration/multifd.h
index d8b0205977..c7fea4914c 100644
--- a/migration/multifd.h
+++ b/migration/multifd.h
@@ -25,6 +25,10 @@ int multifd_queue_page(QEMUFile *f, RAMBlock *block, ram_addr_t offset);
 
 #define MULTIFD_FLAG_SYNC (1 << 0)
 
+/* We reserve 3 bits for METHODS */
+#define MULTIFD_FLAG_METHOD_MASK (7 << 1)
+#define MULTIFD_FLAG_NOCOMP (1 << 1)
+
 /* This value needs to be a multiple of qemu_target_page_size() */
 #define MULTIFD_PACKET_SIZE (512 * 1024)
 
@@ -96,6 +100,8 @@ typedef struct {
     uint64_t num_pages;
     /* syncs main thread and channels */
     QemuSemaphore sem_sync;
+    /* used for compression methods */
+    void *data;
 }  MultiFDSendParams;
 
 typedef struct {
@@ -133,7 +139,26 @@ typedef struct {
     uint64_t num_pages;
     /* syncs main thread and channels */
     QemuSemaphore sem_sync;
+    /* used for de-compression methods */
+    void *data;
 } MultiFDRecvParams;
 
+typedef struct {
+    /* Setup for sending side */
+    int (*send_setup)(MultiFDSendParams *p, Error **errp);
+    /* Cleanup for sending side */
+    void (*send_cleanup)(MultiFDSendParams *p, Error **errp);
+    /* Prepare the send packet */
+    int (*send_prepare)(MultiFDSendParams *p, uint32_t used, Error **errp);
+    /* Write the send packet */
+    int (*send_write)(MultiFDSendParams *p, uint32_t used, Error **errp);
+    /* Setup for receiving side */
+    int (*recv_setup)(MultiFDRecvParams *p, Error **errp);
+    /* Cleanup for receiving side */
+    void (*recv_cleanup)(MultiFDRecvParams *p);
+    /* Read all pages */
+    int (*recv_pages)(MultiFDRecvParams *p, uint32_t used, Error **errp);
+} MultiFDMethods;
+
 #endif
 
diff --git a/migration/ram.c b/migration/ram.c
index ed23ed1c7c..73a141bb60 100644
--- a/migration/ram.c
+++ b/migration/ram.c
@@ -43,6 +43,7 @@
 #include "page_cache.h"
 #include "qemu/error-report.h"
 #include "qapi/error.h"
+#include "qapi/qapi-types-migration.h"
 #include "qapi/qapi-events-migration.h"
 #include "qapi/qmp/qerror.h"
 #include "trace.h"
-- 
2.24.1

[PATCH v4 3/7] multifd: Add multifd-zlib-level parameter

[Juan Quintela]

It will indicate which level use for compression.

Signed-off-by: Juan Quintela <quintela@redhat.com>
---
 migration/migration.c | 15 +++++++++++++++
 monitor/hmp-cmds.c    |  4 ++++
 qapi/migration.json   | 30 +++++++++++++++++++++++++++---
 3 files changed, 46 insertions(+), 3 deletions(-)

diff --git a/migration/migration.c b/migration/migration.c
index 06f6c2d529..4f88f8e958 100644
--- a/migration/migration.c
+++ b/migration/migration.c
@@ -89,6 +89,8 @@
 #define DEFAULT_MIGRATE_X_CHECKPOINT_DELAY (200 * 100)
 #define DEFAULT_MIGRATE_MULTIFD_CHANNELS 2
 #define DEFAULT_MIGRATE_MULTIFD_METHOD MULTIFD_METHOD_NONE
+/*0: means nocompress, 1: best speed, ... 9: best compress ratio */
+#define DEFAULT_MIGRATE_MULTIFD_ZLIB_LEVEL 1
 
 /* Background transfer rate for postcopy, 0 means unlimited, note
  * that page requests can still exceed this limit.
@@ -801,6 +803,8 @@ MigrationParameters *qmp_query_migrate_parameters(Error **errp)
     params->multifd_channels = s->parameters.multifd_channels;
     params->has_multifd_method = true;
     params->multifd_method = s->parameters.multifd_method;
+    params->has_multifd_zlib_level = true;
+    params->multifd_zlib_level = s->parameters.multifd_zlib_level;
     params->has_xbzrle_cache_size = true;
     params->xbzrle_cache_size = s->parameters.xbzrle_cache_size;
     params->has_max_postcopy_bandwidth = true;
@@ -1208,6 +1212,13 @@ static bool migrate_params_check(MigrationParameters *params, Error **errp)
         return false;
     }
 
+    if (params->has_multifd_zlib_level &&
+        (params->multifd_zlib_level > 9)) {
+        error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "multifd_zlib_level",
+                   "is invalid, it should be in the range of 0 to 9");
+        return false;
+    }
+
     if (params->has_xbzrle_cache_size &&
         (params->xbzrle_cache_size < qemu_target_page_size() ||
          !is_power_of_2(params->xbzrle_cache_size))) {
@@ -3536,6 +3547,9 @@ static Property migration_properties[] = {
     DEFINE_PROP_MULTIFD_METHOD("multifd-method", MigrationState,
                       parameters.multifd_method,
                       DEFAULT_MIGRATE_MULTIFD_METHOD),
+    DEFINE_PROP_UINT8("multifd-zlib-level", MigrationState,
+                      parameters.multifd_zlib_level,
+                      DEFAULT_MIGRATE_MULTIFD_ZLIB_LEVEL),
     DEFINE_PROP_SIZE("xbzrle-cache-size", MigrationState,
                       parameters.xbzrle_cache_size,
                       DEFAULT_MIGRATE_XBZRLE_CACHE_SIZE),
@@ -3627,6 +3641,7 @@ static void migration_instance_init(Object *obj)
     params->has_block_incremental = true;
     params->has_multifd_channels = true;
     params->has_multifd_method = true;
+    params->has_multifd_zlib_level = true;
     params->has_xbzrle_cache_size = true;
     params->has_max_postcopy_bandwidth = true;
     params->has_max_cpu_throttle = true;
diff --git a/monitor/hmp-cmds.c b/monitor/hmp-cmds.c
index 16f01d4244..7f11866446 100644
--- a/monitor/hmp-cmds.c
+++ b/monitor/hmp-cmds.c
@@ -1836,6 +1836,10 @@ void hmp_migrate_set_parameter(Monitor *mon, const QDict *qdict)
         }
         p->multifd_method = compress_type;
         break;
+    case MIGRATION_PARAMETER_MULTIFD_ZLIB_LEVEL:
+        p->has_multifd_zlib_level = true;
+        visit_type_int(v, param, &p->multifd_zlib_level, &err);
+        break;
     case MIGRATION_PARAMETER_XBZRLE_CACHE_SIZE:
         p->has_xbzrle_cache_size = true;
         visit_type_size(v, param, &cache_size, &err);
diff --git a/qapi/migration.json b/qapi/migration.json
index 96a126751c..289dce0da7 100644
--- a/qapi/migration.json
+++ b/qapi/migration.json
@@ -602,6 +602,13 @@
 # @multifd-method: Which compression method to use.
 #                  Defaults to none. (Since 5.0)
 #
+# @multifd-zlib-level: Set the compression level to be used in live
+#          migration, the compression level is an integer between 0
+#          and 9, where 0 means no compression, 1 means the best
+#          compression speed, and 9 means best compression ratio which
+#          will consume more CPU.
+#          Defaults to 1. (Since 5.0)
+#
 # Since: 2.4
 ##
 { 'enum': 'MigrationParameter',
@@ -614,7 +621,8 @@
            'downtime-limit', 'x-checkpoint-delay', 'block-incremental',
            'multifd-channels',
            'xbzrle-cache-size', 'max-postcopy-bandwidth',
-           'max-cpu-throttle', 'multifd-method' ] }
+           'max-cpu-throttle', 'multifd-method',
+           'multifd-zlib-level' ] }
 
 ##
 # @MigrateSetParameters:
@@ -707,6 +715,13 @@
 # @multifd-method: Which compression method to use.
 #                  Defaults to none. (Since 5.0)
 #
+# @multifd-zlib-level: Set the compression level to be used in live
+#          migration, the compression level is an integer between 0
+#          and 9, where 0 means no compression, 1 means the best
+#          compression speed, and 9 means best compression ratio which
+#          will consume more CPU.
+#          Defaults to 1. (Since 5.0)
+#
 # Since: 2.4
 ##
 # TODO either fuse back into MigrationParameters, or make
@@ -733,7 +748,8 @@
             '*xbzrle-cache-size': 'size',
             '*max-postcopy-bandwidth': 'size',
             '*max-cpu-throttle': 'int',
-            '*multifd-method': 'MultiFDMethod' } }
+            '*multifd-method': 'MultiFDMethod',
+            '*multifd-zlib-level': 'int' } }
 
 ##
 # @migrate-set-parameters:
@@ -846,6 +862,13 @@
 # @multifd-method: Which compression method to use.
 #                  Defaults to none. (Since 5.0)
 #
+# @multifd-zlib-level: Set the compression level to be used in live
+#          migration, the compression level is an integer between 0
+#          and 9, where 0 means no compression, 1 means the best
+#          compression speed, and 9 means best compression ratio which
+#          will consume more CPU.
+#          Defaults to 1. (Since 5.0)
+#
 # Since: 2.4
 ##
 { 'struct': 'MigrationParameters',
@@ -870,7 +893,8 @@
             '*xbzrle-cache-size': 'size',
 	    '*max-postcopy-bandwidth': 'size',
             '*max-cpu-throttle': 'uint8',
-            '*multifd-method': 'MultiFDMethod' } }
+            '*multifd-method': 'MultiFDMethod',
+            '*multifd-zlib-level': 'uint8' } }
 
 ##
 # @query-migrate-parameters:
-- 
2.24.1

[PATCH v4 4/7] multifd: Add zlib compression multifd support

[Juan Quintela]

Signed-off-by: Juan Quintela <quintela@redhat.com>
---
 hw/core/qdev-properties.c    |   2 +-
 migration/Makefile.objs      |   1 +
 migration/migration.c        |   9 ++
 migration/migration.h        |   1 +
 migration/multifd-zlib.c     | 293 +++++++++++++++++++++++++++++++++++
 migration/multifd.c          |   6 +
 migration/multifd.h          |   4 +
 qapi/migration.json          |   3 +-
 tests/qtest/migration-test.c |   6 +
 9 files changed, 323 insertions(+), 2 deletions(-)
 create mode 100644 migration/multifd-zlib.c

diff --git a/hw/core/qdev-properties.c b/hw/core/qdev-properties.c
index 4442844d37..bf88a50cdf 100644
--- a/hw/core/qdev-properties.c
+++ b/hw/core/qdev-properties.c
@@ -645,7 +645,7 @@ const PropertyInfo qdev_prop_fdc_drive_type = {
 const PropertyInfo qdev_prop_multifd_method = {
     .name = "MultiFDMethod",
     .description = "multifd_method values, "
-                   "none",
+                   "none/zlib",
     .enum_table = &MultiFDMethod_lookup,
     .get = get_enum,
     .set = set_enum,
diff --git a/migration/Makefile.objs b/migration/Makefile.objs
index d3623d5f9b..0308caa5c5 100644
--- a/migration/Makefile.objs
+++ b/migration/Makefile.objs
@@ -8,6 +8,7 @@ common-obj-y += xbzrle.o postcopy-ram.o
 common-obj-y += qjson.o
 common-obj-y += block-dirty-bitmap.o
 common-obj-y += multifd.o
+common-obj-y += multifd-zlib.o
 
 common-obj-$(CONFIG_RDMA) += rdma.o
 
diff --git a/migration/migration.c b/migration/migration.c
index 4f88f8e958..3b081e8147 100644
--- a/migration/migration.c
+++ b/migration/migration.c
@@ -2265,6 +2265,15 @@ MultiFDMethod migrate_multifd_method(void)
     return s->parameters.multifd_method;
 }
 
+int migrate_multifd_zlib_level(void)
+{
+    MigrationState *s;
+
+    s = migrate_get_current();
+
+    return s->parameters.multifd_zlib_level;
+}
+
 int migrate_use_xbzrle(void)
 {
     MigrationState *s;
diff --git a/migration/migration.h b/migration/migration.h
index 3d23a0852e..95e9c196ff 100644
--- a/migration/migration.h
+++ b/migration/migration.h
@@ -301,6 +301,7 @@ bool migrate_use_multifd(void);
 bool migrate_pause_before_switchover(void);
 int migrate_multifd_channels(void);
 MultiFDMethod migrate_multifd_method(void);
+int migrate_multifd_zlib_level(void);
 
 int migrate_use_xbzrle(void);
 int64_t migrate_xbzrle_cache_size(void);
diff --git a/migration/multifd-zlib.c b/migration/multifd-zlib.c
new file mode 100644
index 0000000000..1589ea78b2
--- /dev/null
+++ b/migration/multifd-zlib.c
@@ -0,0 +1,293 @@
+/*
+ * Multifd zlib compression implementation
+ *
+ * Copyright (c) 2020 Red Hat Inc
+ *
+ * Authors:
+ *  Juan Quintela <quintela@redhat.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ */
+
+#include "qemu/osdep.h"
+#include <zlib.h>
+#include "qemu/rcu.h"
+#include "exec/target_page.h"
+#include "qapi/error.h"
+#include "migration.h"
+#include "trace.h"
+#include "multifd.h"
+
+struct zlib_data {
+    /* stream for compression */
+    z_stream zs;
+    /* compressed buffer */
+    uint8_t *zbuff;
+    /* size of compressed buffer */
+    uint32_t zbuff_len;
+};
+
+/* Multifd zlib compression */
+
+/**
+ * zlib_send_setup: setup send side
+ *
+ * Setup each channel with zlib compression.
+ *
+ * Returns 0 for success or -1 for error
+ *
+ * @p: Params for the channel that we are using
+ * @errp: pointer to an error
+ */
+static int zlib_send_setup(MultiFDSendParams *p, Error **errp)
+{
+    uint32_t page_count = MULTIFD_PACKET_SIZE / qemu_target_page_size();
+    struct zlib_data *z = g_malloc0(sizeof(struct zlib_data));
+    z_stream *zs = &z->zs;
+
+    zs->zalloc = Z_NULL;
+    zs->zfree = Z_NULL;
+    zs->opaque = Z_NULL;
+    if (deflateInit(zs, migrate_multifd_zlib_level()) != Z_OK) {
+        g_free(z);
+        error_setg(errp, "multifd %d: deflate init failed", p->id);
+        return -1;
+    }
+    /* We will never have more than page_count pages */
+    z->zbuff_len = page_count * qemu_target_page_size();
+    z->zbuff_len *= 2;
+    z->zbuff = g_try_malloc(z->zbuff_len);
+    if (!z->zbuff) {
+        deflateEnd(&z->zs);
+        g_free(z);
+        error_setg(errp, "multifd %d: out of memory for zbuff", p->id);
+        return -1;
+    }
+    p->data = z;
+    return 0;
+}
+
+/**
+ * zlib_send_cleanup: cleanup send side
+ *
+ * Close the channel and return memory.
+ *
+ * @p: Params for the channel that we are using
+ */
+static void zlib_send_cleanup(MultiFDSendParams *p, Error **errp)
+{
+    struct zlib_data *z = p->data;
+
+    deflateEnd(&z->zs);
+    g_free(z->zbuff);
+    z->zbuff = NULL;
+    g_free(p->data);
+    p->data = NULL;
+}
+
+/**
+ * zlib_send_prepare: prepare date to be able to send
+ *
+ * Create a compressed buffer with all the pages that we are going to
+ * send.
+ *
+ * Returns 0 for success or -1 for error
+ *
+ * @p: Params for the channel that we are using
+ * @used: number of pages used
+ */
+static int zlib_send_prepare(MultiFDSendParams *p, uint32_t used, Error **errp)
+{
+    struct iovec *iov = p->pages->iov;
+    struct zlib_data *z = p->data;
+    z_stream *zs = &z->zs;
+    uint32_t out_size = 0;
+    int ret;
+    uint32_t i;
+
+    for (i = 0; i < used; i++) {
+        uint32_t available = z->zbuff_len - out_size;
+        int flush = Z_NO_FLUSH;
+
+        if (i == used - 1) {
+            flush = Z_SYNC_FLUSH;
+        }
+
+        zs->avail_in = iov[i].iov_len;
+        zs->next_in = iov[i].iov_base;
+
+        zs->avail_out = available;
+        zs->next_out = z->zbuff + out_size;
+
+        ret = deflate(zs, flush);
+        if (ret != Z_OK) {
+            error_setg(errp, "multifd %d: deflate returned %d instead of Z_OK",
+                       p->id, ret);
+            return -1;
+        }
+        out_size += available - zs->avail_out;
+    }
+    p->next_packet_size = out_size;
+    p->flags |= MULTIFD_FLAG_ZLIB;
+
+    return 0;
+}
+
+/**
+ * zlib_send_write: do the actual write of the data
+ *
+ * Do the actual write of the comprresed buffer.
+ *
+ * Returns 0 for success or -1 for error
+ *
+ * @p: Params for the channel that we are using
+ * @used: number of pages used
+ * @errp: pointer to an error
+ */
+static int zlib_send_write(MultiFDSendParams *p, uint32_t used, Error **errp)
+{
+    struct zlib_data *z = p->data;
+
+    return qio_channel_write_all(p->c, (void *)z->zbuff, p->next_packet_size,
+                                 errp);
+}
+
+/**
+ * zlib_recv_setup: setup receive side
+ *
+ * Create the compressed channel and buffer.
+ *
+ * Returns 0 for success or -1 for error
+ *
+ * @p: Params for the channel that we are using
+ * @errp: pointer to an error
+ */
+static int zlib_recv_setup(MultiFDRecvParams *p, Error **errp)
+{
+    uint32_t page_count = MULTIFD_PACKET_SIZE / qemu_target_page_size();
+    struct zlib_data *z = g_malloc0(sizeof(struct zlib_data));
+    z_stream *zs = &z->zs;
+
+    p->data = z;
+    zs->zalloc = Z_NULL;
+    zs->zfree = Z_NULL;
+    zs->opaque = Z_NULL;
+    zs->avail_in = 0;
+    zs->next_in = Z_NULL;
+    if (inflateInit(zs) != Z_OK) {
+        error_setg(errp, "multifd %d: inflate init failed", p->id);
+        return -1;
+    }
+    /* We will never have more than page_count pages */
+    z->zbuff_len = page_count * qemu_target_page_size();
+    /* We know compression "could" use more space */
+    z->zbuff_len *= 2;
+    z->zbuff = g_try_malloc(z->zbuff_len);
+    if (!z->zbuff) {
+        inflateEnd(zs);
+        error_setg(errp, "multifd %d: out of memory for zbuff", p->id);
+        return -1;
+    }
+    return 0;
+}
+
+/**
+ * zlib_recv_cleanup: setup receive side
+ *
+ * For no compression this function does nothing.
+ *
+ * @p: Params for the channel that we are using
+ */
+static void zlib_recv_cleanup(MultiFDRecvParams *p)
+{
+    struct zlib_data *z = p->data;
+
+    inflateEnd(&z->zs);
+    g_free(z->zbuff);
+    z->zbuff = NULL;
+    g_free(p->data);
+    p->data = NULL;
+}
+
+/**
+ * zlib_recv_pages: read the data from the channel into actual pages
+ *
+ * Read the compressed buffer, and uncompress it into the actual
+ * pages.
+ *
+ * Returns 0 for success or -1 for error
+ *
+ * @p: Params for the channel that we are using
+ * @used: number of pages used
+ * @errp: pointer to an error
+ */
+static int zlib_recv_pages(MultiFDRecvParams *p, uint32_t used, Error **errp)
+{
+    struct zlib_data *z = p->data;
+    z_stream *zs = &z->zs;
+    uint32_t in_size = p->next_packet_size;
+    /* we measure the change of total_out */
+    uint32_t out_size = zs->total_out;
+    uint32_t expected_size = used * qemu_target_page_size();
+    uint32_t flags = p->flags & MULTIFD_FLAG_METHOD_MASK;
+    int ret;
+    int i;
+
+    if (flags != MULTIFD_FLAG_ZLIB) {
+        error_setg(errp, "multifd %d: flags received %x flags expected %x",
+                   p->id, flags, MULTIFD_FLAG_ZLIB);
+        return -1;
+    }
+    ret = qio_channel_read_all(p->c, (void *)z->zbuff, in_size, errp);
+
+    if (ret != 0) {
+        return ret;
+    }
+
+    zs->avail_in = in_size;
+    zs->next_in = z->zbuff;
+
+    for (i = 0; i < used; i++) {
+        struct iovec *iov = &p->pages->iov[i];
+        int flush = Z_NO_FLUSH;
+
+        if (i == used  - 1) {
+            flush = Z_SYNC_FLUSH;
+        }
+
+        zs->avail_out = iov->iov_len;
+        zs->next_out = iov->iov_base;
+
+        ret = inflate(zs, flush);
+        if (ret != Z_OK) {
+            error_setg(errp, "multifd %d: inflate returned %d instead of Z_OK",
+                       p->id, ret);
+            return ret;
+        }
+    }
+    out_size = zs->total_out - out_size;
+    if (out_size != expected_size) {
+        error_setg(errp, "multifd %d: packet size received %d size expected %d",
+                   p->id, out_size, expected_size);
+        return -1;
+    }
+    return 0;
+}
+
+static MultiFDMethods multifd_zlib_ops = {
+    .send_setup = zlib_send_setup,
+    .send_cleanup = zlib_send_cleanup,
+    .send_prepare = zlib_send_prepare,
+    .send_write = zlib_send_write,
+    .recv_setup = zlib_recv_setup,
+    .recv_cleanup = zlib_recv_cleanup,
+    .recv_pages = zlib_recv_pages
+};
+
+static void multifd_zlib_register(void)
+{
+    multifd_register_ops(MULTIFD_METHOD_ZLIB, &multifd_zlib_ops);
+}
+
+migration_init(multifd_zlib_register);
diff --git a/migration/multifd.c b/migration/multifd.c
index 1c49c2a665..7bb9c3582f 100644
--- a/migration/multifd.c
+++ b/migration/multifd.c
@@ -166,6 +166,12 @@ static MultiFDMethods *multifd_ops[MULTIFD_METHOD__MAX] = {
     [MULTIFD_METHOD_NONE] = &multifd_nocomp_ops,
 };
 
+void multifd_register_ops(int method, MultiFDMethods *ops)
+{
+    assert(0 < method && method < MULTIFD_METHOD__MAX);
+    multifd_ops[method] = ops;
+}
+
 static int multifd_send_initial_packet(MultiFDSendParams *p, Error **errp)
 {
     MultiFDInit_t msg = {};
diff --git a/migration/multifd.h b/migration/multifd.h
index c7fea4914c..3fa5132f1d 100644
--- a/migration/multifd.h
+++ b/migration/multifd.h
@@ -23,11 +23,13 @@ void multifd_recv_sync_main(void);
 void multifd_send_sync_main(QEMUFile *f);
 int multifd_queue_page(QEMUFile *f, RAMBlock *block, ram_addr_t offset);
 
+/* Multifd Compression flags */
 #define MULTIFD_FLAG_SYNC (1 << 0)
 
 /* We reserve 3 bits for METHODS */
 #define MULTIFD_FLAG_METHOD_MASK (7 << 1)
 #define MULTIFD_FLAG_NOCOMP (1 << 1)
+#define MULTIFD_FLAG_ZLIB (2 << 1)
 
 /* This value needs to be a multiple of qemu_target_page_size() */
 #define MULTIFD_PACKET_SIZE (512 * 1024)
@@ -160,5 +162,7 @@ typedef struct {
     int (*recv_pages)(MultiFDRecvParams *p, uint32_t used, Error **errp);
 } MultiFDMethods;
 
+void multifd_register_ops(int method, MultiFDMethods *ops);
+
 #endif
 
diff --git a/qapi/migration.json b/qapi/migration.json
index 289dce0da7..032ee7d3e6 100644
--- a/qapi/migration.json
+++ b/qapi/migration.json
@@ -494,12 +494,13 @@
 # An enumeration of multifd compression.
 #
 # @none: no compression.
+# @zlib: use zlib compression method.
 #
 # Since: 5.0
 #
 ##
 { 'enum': 'MultiFDMethod',
-  'data': [ 'none' ] }
+  'data': [ 'none', 'zlib' ] }
 
 ##
 # @MigrationParameter:
diff --git a/tests/qtest/migration-test.c b/tests/qtest/migration-test.c
index d2f9ef38f5..8effed205d 100644
--- a/tests/qtest/migration-test.c
+++ b/tests/qtest/migration-test.c
@@ -1313,6 +1313,11 @@ static void test_multifd_tcp_none(void)
     test_multifd_tcp("none");
 }
 
+static void test_multifd_tcp_zlib(void)
+{
+    test_multifd_tcp("zlib");
+}
+
 /*
  * This test does:
  *  source               target
@@ -1475,6 +1480,7 @@ int main(int argc, char **argv)
     qtest_add_func("/migration/auto_converge", test_migrate_auto_converge);
     qtest_add_func("/migration/multifd/tcp/none", test_multifd_tcp_none);
     qtest_add_func("/migration/multifd/tcp/cancel", test_multifd_tcp_cancel);
+    qtest_add_func("/migration/multifd/tcp/zlib", test_multifd_tcp_zlib);
 
     ret = g_test_run();
 
-- 
2.24.1

[PATCH v4 5/7] configure: Enable test and libs for zstd

[Juan Quintela]

Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
---
 configure | 30 ++++++++++++++++++++++++++++++
 1 file changed, 30 insertions(+)

diff --git a/configure b/configure
index a72a5def57..7c1dca326f 100755
--- a/configure
+++ b/configure
@@ -448,6 +448,7 @@ lzo=""
 snappy=""
 bzip2=""
 lzfse=""
+zstd=""
 guest_agent=""
 guest_agent_with_vss="no"
 guest_agent_ntddscsi="no"
@@ -1343,6 +1344,10 @@ for opt do
   ;;
   --disable-lzfse) lzfse="no"
   ;;
+  --disable-zstd) zstd="no"
+  ;;
+  --enable-zstd) zstd="yes"
+  ;;
   --enable-guest-agent) guest_agent="yes"
   ;;
   --disable-guest-agent) guest_agent="no"
@@ -1795,6 +1800,8 @@ disabled with --disable-FEATURE, default is enabled if available:
                   (for reading bzip2-compressed dmg images)
   lzfse           support of lzfse compression library
                   (for reading lzfse-compressed dmg images)
+  zstd            support for zstd compression library
+                  (for migration compression)
   seccomp         seccomp support
   coroutine-pool  coroutine freelist (better performance)
   glusterfs       GlusterFS backend
@@ -2409,6 +2416,24 @@ EOF
     fi
 fi
 
+##########################################
+# zstd check
+
+if test "$zstd" != "no" ; then
+    if $pkg_config --exist libzstd ; then
+        zstd_cflags="$($pkg_config --cflags libzstd)"
+        zstd_libs="$($pkg_config --libs libzstd)"
+        LIBS="$zstd_libs $LIBS"
+        QEMU_CFLAGS="$QEMU_CFLAGS $zstd_cflags"
+        zstd="yes"
+    else
+        if test "$zstd" = "yes" ; then
+            feature_not_found "libzstd" "Install libzstd devel"
+        fi
+        zstd="no"
+    fi
+fi
+
 ##########################################
 # libseccomp check
 
@@ -6578,6 +6603,7 @@ echo "lzo support       $lzo"
 echo "snappy support    $snappy"
 echo "bzip2 support     $bzip2"
 echo "lzfse support     $lzfse"
+echo "zstd support      $zstd"
 echo "NUMA host support $numa"
 echo "libxml2           $libxml2"
 echo "tcmalloc support  $tcmalloc"
@@ -7143,6 +7169,10 @@ if test "$lzfse" = "yes" ; then
   echo "LZFSE_LIBS=-llzfse" >> $config_host_mak
 fi
 
+if test "$zstd" = "yes" ; then
+  echo "CONFIG_ZSTD=y" >> $config_host_mak
+fi
+
 if test "$libiscsi" = "yes" ; then
   echo "CONFIG_LIBISCSI=m" >> $config_host_mak
   echo "LIBISCSI_CFLAGS=$libiscsi_cflags" >> $config_host_mak
-- 
2.24.1

[PATCH v4 6/7] multifd: Add multifd-zstd-level parameter

[Juan Quintela]

Signed-off-by: Juan Quintela <quintela@redhat.com>
---
 migration/migration.c | 15 +++++++++++++++
 monitor/hmp-cmds.c    |  4 ++++
 qapi/migration.json   | 29 ++++++++++++++++++++++++++---
 3 files changed, 45 insertions(+), 3 deletions(-)

diff --git a/migration/migration.c b/migration/migration.c
index 3b081e8147..b690500545 100644
--- a/migration/migration.c
+++ b/migration/migration.c
@@ -91,6 +91,8 @@
 #define DEFAULT_MIGRATE_MULTIFD_METHOD MULTIFD_METHOD_NONE
 /*0: means nocompress, 1: best speed, ... 9: best compress ratio */
 #define DEFAULT_MIGRATE_MULTIFD_ZLIB_LEVEL 1
+/* 0: means nocompress, 1: best speed, ... 20: best compress ratio */
+#define DEFAULT_MIGRATE_MULTIFD_ZSTD_LEVEL 1
 
 /* Background transfer rate for postcopy, 0 means unlimited, note
  * that page requests can still exceed this limit.
@@ -805,6 +807,8 @@ MigrationParameters *qmp_query_migrate_parameters(Error **errp)
     params->multifd_method = s->parameters.multifd_method;
     params->has_multifd_zlib_level = true;
     params->multifd_zlib_level = s->parameters.multifd_zlib_level;
+    params->has_multifd_zstd_level = true;
+    params->multifd_zstd_level = s->parameters.multifd_zstd_level;
     params->has_xbzrle_cache_size = true;
     params->xbzrle_cache_size = s->parameters.xbzrle_cache_size;
     params->has_max_postcopy_bandwidth = true;
@@ -1219,6 +1223,13 @@ static bool migrate_params_check(MigrationParameters *params, Error **errp)
         return false;
     }
 
+    if (params->has_multifd_zstd_level &&
+        (params->multifd_zstd_level > 20)) {
+        error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "multifd_zstd_level",
+                   "is invalid, it should be in the range of 0 to 20");
+        return false;
+    }
+
     if (params->has_xbzrle_cache_size &&
         (params->xbzrle_cache_size < qemu_target_page_size() ||
          !is_power_of_2(params->xbzrle_cache_size))) {
@@ -3559,6 +3570,9 @@ static Property migration_properties[] = {
     DEFINE_PROP_UINT8("multifd-zlib-level", MigrationState,
                       parameters.multifd_zlib_level,
                       DEFAULT_MIGRATE_MULTIFD_ZLIB_LEVEL),
+    DEFINE_PROP_UINT8("multifd-zstd-level", MigrationState,
+                      parameters.multifd_zstd_level,
+                      DEFAULT_MIGRATE_MULTIFD_ZSTD_LEVEL),
     DEFINE_PROP_SIZE("xbzrle-cache-size", MigrationState,
                       parameters.xbzrle_cache_size,
                       DEFAULT_MIGRATE_XBZRLE_CACHE_SIZE),
@@ -3651,6 +3665,7 @@ static void migration_instance_init(Object *obj)
     params->has_multifd_channels = true;
     params->has_multifd_method = true;
     params->has_multifd_zlib_level = true;
+    params->has_multifd_zstd_level = true;
     params->has_xbzrle_cache_size = true;
     params->has_max_postcopy_bandwidth = true;
     params->has_max_cpu_throttle = true;
diff --git a/monitor/hmp-cmds.c b/monitor/hmp-cmds.c
index 7f11866446..87db07694b 100644
--- a/monitor/hmp-cmds.c
+++ b/monitor/hmp-cmds.c
@@ -1840,6 +1840,10 @@ void hmp_migrate_set_parameter(Monitor *mon, const QDict *qdict)
         p->has_multifd_zlib_level = true;
         visit_type_int(v, param, &p->multifd_zlib_level, &err);
         break;
+    case MIGRATION_PARAMETER_MULTIFD_ZSTD_LEVEL:
+        p->has_multifd_zstd_level = true;
+        visit_type_int(v, param, &p->multifd_zstd_level, &err);
+        break;
     case MIGRATION_PARAMETER_XBZRLE_CACHE_SIZE:
         p->has_xbzrle_cache_size = true;
         visit_type_size(v, param, &cache_size, &err);
diff --git a/qapi/migration.json b/qapi/migration.json
index 032ee7d3e6..bb5cb6b4f4 100644
--- a/qapi/migration.json
+++ b/qapi/migration.json
@@ -610,6 +610,13 @@
 #          will consume more CPU.
 #          Defaults to 1. (Since 5.0)
 #
+# @multifd-zstd-level: Set the compression level to be used in live
+#          migration, the compression level is an integer between 0
+#          and 20, where 0 means no compression, 1 means the best
+#          compression speed, and 20 means best compression ratio which
+#          will consume more CPU.
+#          Defaults to 1. (Since 5.0)
+#
 # Since: 2.4
 ##
 { 'enum': 'MigrationParameter',
@@ -623,7 +630,7 @@
            'multifd-channels',
            'xbzrle-cache-size', 'max-postcopy-bandwidth',
            'max-cpu-throttle', 'multifd-method',
-           'multifd-zlib-level' ] }
+           'multifd-zlib-level' ,'multifd-zstd-level' ] }
 
 ##
 # @MigrateSetParameters:
@@ -723,6 +730,13 @@
 #          will consume more CPU.
 #          Defaults to 1. (Since 5.0)
 #
+# @multifd-zstd-level: Set the compression level to be used in live
+#          migration, the compression level is an integer between 0
+#          and 20, where 0 means no compression, 1 means the best
+#          compression speed, and 20 means best compression ratio which
+#          will consume more CPU.
+#          Defaults to 1. (Since 5.0)
+#
 # Since: 2.4
 ##
 # TODO either fuse back into MigrationParameters, or make
@@ -750,7 +764,8 @@
             '*max-postcopy-bandwidth': 'size',
             '*max-cpu-throttle': 'int',
             '*multifd-method': 'MultiFDMethod',
-            '*multifd-zlib-level': 'int' } }
+            '*multifd-zlib-level': 'int',
+            '*multifd-zstd-level': 'int' } }
 
 ##
 # @migrate-set-parameters:
@@ -870,6 +885,13 @@
 #          will consume more CPU.
 #          Defaults to 1. (Since 5.0)
 #
+# @multifd-zstd-level: Set the compression level to be used in live
+#          migration, the compression level is an integer between 0
+#          and 20, where 0 means no compression, 1 means the best
+#          compression speed, and 20 means best compression ratio which
+#          will consume more CPU.
+#          Defaults to 1. (Since 5.0)
+#
 # Since: 2.4
 ##
 { 'struct': 'MigrationParameters',
@@ -895,7 +917,8 @@
 	    '*max-postcopy-bandwidth': 'size',
             '*max-cpu-throttle': 'uint8',
             '*multifd-method': 'MultiFDMethod',
-            '*multifd-zlib-level': 'uint8' } }
+            '*multifd-zlib-level': 'uint8',
+            '*multifd-zstd-level': 'uint8' } }
 
 ##
 # @query-migrate-parameters:
-- 
2.24.1

[PATCH v4 7/7] multifd: Add zstd compression multifd support

[Juan Quintela]

Signed-off-by: Juan Quintela <quintela@redhat.com>

---

Remove CONFIG_ZSTD gross test for enable zstd option.  Thanhs Markus!!!
---
 hw/core/qdev-properties.c    |   2 +-
 migration/Makefile.objs      |   1 +
 migration/migration.c        |   9 ++
 migration/migration.h        |   1 +
 migration/multifd-zstd.c     | 305 +++++++++++++++++++++++++++++++++++
 migration/multifd.h          |   2 +-
 migration/ram.c              |   1 -
 qapi/migration.json          |   4 +-
 tests/qtest/migration-test.c |  10 ++
 9 files changed, 331 insertions(+), 4 deletions(-)
 create mode 100644 migration/multifd-zstd.c

diff --git a/hw/core/qdev-properties.c b/hw/core/qdev-properties.c
index bf88a50cdf..9440ca78c3 100644
--- a/hw/core/qdev-properties.c
+++ b/hw/core/qdev-properties.c
@@ -645,7 +645,7 @@ const PropertyInfo qdev_prop_fdc_drive_type = {
 const PropertyInfo qdev_prop_multifd_method = {
     .name = "MultiFDMethod",
     .description = "multifd_method values, "
-                   "none/zlib",
+                   "none/zlib/zstd",
     .enum_table = &MultiFDMethod_lookup,
     .get = get_enum,
     .set = set_enum,
diff --git a/migration/Makefile.objs b/migration/Makefile.objs
index 0308caa5c5..0fc619e380 100644
--- a/migration/Makefile.objs
+++ b/migration/Makefile.objs
@@ -9,6 +9,7 @@ common-obj-y += qjson.o
 common-obj-y += block-dirty-bitmap.o
 common-obj-y += multifd.o
 common-obj-y += multifd-zlib.o
+common-obj-$(CONFIG_ZSTD) += multifd-zstd.o
 
 common-obj-$(CONFIG_RDMA) += rdma.o
 
diff --git a/migration/migration.c b/migration/migration.c
index b690500545..aff081128c 100644
--- a/migration/migration.c
+++ b/migration/migration.c
@@ -2285,6 +2285,15 @@ int migrate_multifd_zlib_level(void)
     return s->parameters.multifd_zlib_level;
 }
 
+int migrate_multifd_zstd_level(void)
+{
+    MigrationState *s;
+
+    s = migrate_get_current();
+
+    return s->parameters.multifd_zstd_level;
+}
+
 int migrate_use_xbzrle(void)
 {
     MigrationState *s;
diff --git a/migration/migration.h b/migration/migration.h
index 95e9c196ff..2eb72aee0a 100644
--- a/migration/migration.h
+++ b/migration/migration.h
@@ -302,6 +302,7 @@ bool migrate_pause_before_switchover(void);
 int migrate_multifd_channels(void);
 MultiFDMethod migrate_multifd_method(void);
 int migrate_multifd_zlib_level(void);
+int migrate_multifd_zstd_level(void);
 
 int migrate_use_xbzrle(void);
 int64_t migrate_xbzrle_cache_size(void);
diff --git a/migration/multifd-zstd.c b/migration/multifd-zstd.c
new file mode 100644
index 0000000000..a594c1af30
--- /dev/null
+++ b/migration/multifd-zstd.c
@@ -0,0 +1,305 @@
+/*
+ * Multifd zlib compression implementation
+ *
+ * Copyright (c) 2020 Red Hat Inc
+ *
+ * Authors:
+ *  Juan Quintela <quintela@redhat.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ */
+
+#include "qemu/osdep.h"
+#include <zstd.h>
+#include "qemu/rcu.h"
+#include "exec/target_page.h"
+#include "qapi/error.h"
+#include "migration.h"
+#include "trace.h"
+#include "multifd.h"
+
+struct zstd_data {
+    /* stream for compression */
+    ZSTD_CStream *zcs;
+    /* stream for decompression */
+    ZSTD_DStream *zds;
+    /* buffers */
+    ZSTD_inBuffer in;
+    ZSTD_outBuffer out;
+    /* compressed buffer */
+    uint8_t *zbuff;
+    /* size of compressed buffer */
+    uint32_t zbuff_len;
+};
+
+/* Multifd zstd compression */
+
+/**
+ * zstd_send_setup: setup send side
+ *
+ * Setup each channel with zstd compression.
+ *
+ * Returns 0 for success or -1 for error
+ *
+ * @p: Params for the channel that we are using
+ * @errp: pointer to an error
+ */
+static int zstd_send_setup(MultiFDSendParams *p, Error **errp)
+{
+    uint32_t page_count = MULTIFD_PACKET_SIZE / qemu_target_page_size();
+    struct zstd_data *z = g_new0(struct zstd_data, 1);
+    int res;
+
+    p->data = z;
+    z->zcs = ZSTD_createCStream();
+    if (!z->zcs) {
+        g_free(z);
+        error_setg(errp, "multifd %d: zstd createCStream failed", p->id);
+        return -1;
+    }
+
+    res = ZSTD_initCStream(z->zcs, migrate_multifd_zstd_level());
+    if (ZSTD_isError(res)) {
+        ZSTD_freeCStream(z->zcs);
+        g_free(z);
+        error_setg(errp, "multifd %d: initCStream failed", p->id);
+        return -1;
+    }
+    /* We will never have more than page_count pages */
+    z->zbuff_len = page_count * qemu_target_page_size();
+    z->zbuff_len *= 2;
+    z->zbuff = g_try_malloc(z->zbuff_len);
+    if (!z->zbuff) {
+        ZSTD_freeCStream(z->zcs);
+        g_free(z);
+        error_setg(errp, "multifd %d: out of memory for zbuff", p->id);
+        return -1;
+    }
+    return 0;
+}
+
+/**
+ * zstd_send_cleanup: cleanup send side
+ *
+ * Close the channel and return memory.
+ *
+ * @p: Params for the channel that we are using
+ */
+static void zstd_send_cleanup(MultiFDSendParams *p, Error **errp)
+{
+    struct zstd_data *z = p->data;
+
+    ZSTD_freeCStream(z->zcs);
+    z->zcs = NULL;
+    g_free(z->zbuff);
+    z->zbuff = NULL;
+    g_free(p->data);
+    p->data = NULL;
+}
+
+/**
+ * zstd_send_prepare: prepare date to be able to send
+ *
+ * Create a compressed buffer with all the pages that we are going to
+ * send.
+ *
+ * Returns 0 for success or -1 for error
+ *
+ * @p: Params for the channel that we are using
+ * @used: number of pages used
+ */
+static int zstd_send_prepare(MultiFDSendParams *p, uint32_t used, Error **errp)
+{
+    struct iovec *iov = p->pages->iov;
+    struct zstd_data *z = p->data;
+    int ret;
+    uint32_t i;
+
+    z->out.dst = z->zbuff;
+    z->out.size = z->zbuff_len;
+    z->out.pos = 0;
+
+    for (i = 0; i < used; i++) {
+        ZSTD_EndDirective flush = ZSTD_e_continue;
+
+        if (i == used - 1) {
+            flush = ZSTD_e_flush;
+        }
+        z->in.src = iov[i].iov_base;
+        z->in.size = iov[i].iov_len;
+        z->in.pos = 0;
+
+        ret = ZSTD_compressStream2(z->zcs, &z->out, &z->in, flush);
+        if (ZSTD_isError(ret)) {
+            error_setg(errp, "multifd %d: compressStream error %s",
+                       p->id, ZSTD_getErrorName(ret));
+            return -1;
+        }
+    }
+    p->next_packet_size = z->out.pos;
+    p->flags |= MULTIFD_FLAG_ZSTD;
+
+    return 0;
+}
+
+/**
+ * zstd_send_write: do the actual write of the data
+ *
+ * Do the actual write of the comprresed buffer.
+ *
+ * Returns 0 for success or -1 for error
+ *
+ * @p: Params for the channel that we are using
+ * @used: number of pages used
+ * @errp: pointer to an error
+ */
+static int zstd_send_write(MultiFDSendParams *p, uint32_t used, Error **errp)
+{
+    struct zstd_data *z = p->data;
+
+    return qio_channel_write_all(p->c, (void *)z->zbuff, p->next_packet_size,
+                                 errp);
+}
+
+/**
+ * zstd_recv_setup: setup receive side
+ *
+ * Create the compressed channel and buffer.
+ *
+ * Returns 0 for success or -1 for error
+ *
+ * @p: Params for the channel that we are using
+ * @errp: pointer to an error
+ */
+static int zstd_recv_setup(MultiFDRecvParams *p, Error **errp)
+{
+    uint32_t page_count = MULTIFD_PACKET_SIZE / qemu_target_page_size();
+    struct zstd_data *z = g_new0(struct zstd_data, 1);
+    int res;
+
+    p->data = z;
+    z->zds = ZSTD_createDStream();
+    if (!z->zds) {
+        g_free(z);
+        error_setg(errp, "multifd %d: zstd createDStream failed", p->id);
+        return -1;
+    }
+
+    res = ZSTD_initDStream(z->zds);
+    if (ZSTD_isError(res)) {
+        ZSTD_freeDStream(z->zds);
+        g_free(z);
+        error_setg(errp, "multifd %d: initDStream failed", p->id);
+        return -1;
+    }
+
+    /* We will never have more than page_count pages */
+    z->zbuff_len = page_count * qemu_target_page_size();
+    /* We know compression "could" use more space */
+    z->zbuff_len *= 2;
+    z->zbuff = g_try_malloc(z->zbuff_len);
+    if (!z->zbuff) {
+        ZSTD_freeDStream(z->zds);
+        g_free(z);
+        error_setg(errp, "multifd %d: out of memory for zbuff", p->id);
+        return -1;
+    }
+    return 0;
+}
+
+/**
+ * zstd_recv_cleanup: setup receive side
+ *
+ * For no compression this function does nothing.
+ *
+ * @p: Params for the channel that we are using
+ */
+static void zstd_recv_cleanup(MultiFDRecvParams *p)
+{
+    struct zstd_data *z = p->data;
+
+    ZSTD_freeDStream(z->zds);
+    z->zds = NULL;
+    g_free(z->zbuff);
+    z->zbuff = NULL;
+    g_free(p->data);
+    p->data = NULL;
+}
+
+/**
+ * zstd_recv_pages: read the data from the channel into actual pages
+ *
+ * Read the compressed buffer, and uncompress it into the actual
+ * pages.
+ *
+ * Returns 0 for success or -1 for error
+ *
+ * @p: Params for the channel that we are using
+ * @used: number of pages used
+ * @errp: pointer to an error
+ */
+static int zstd_recv_pages(MultiFDRecvParams *p, uint32_t used, Error **errp)
+{
+    uint32_t in_size = p->next_packet_size;
+    uint32_t out_size = 0;
+    uint32_t expected_size = used * qemu_target_page_size();
+    uint32_t flags = p->flags & MULTIFD_FLAG_METHOD_MASK;
+    struct zstd_data *z = p->data;
+    int ret;
+    int i;
+
+    if (flags != MULTIFD_FLAG_ZSTD) {
+        error_setg(errp, "multifd %d: flags received %x flags expected %x",
+                   p->id, flags, MULTIFD_FLAG_ZSTD);
+        return -1;
+    }
+    ret = qio_channel_read_all(p->c, (void *)z->zbuff, in_size, errp);
+
+    if (ret != 0) {
+        return ret;
+    }
+
+    z->in.src = z->zbuff;
+    z->in.size = in_size;
+    z->in.pos = 0;
+
+    for (i = 0; i < used; i++) {
+        struct iovec *iov = &p->pages->iov[i];
+
+        z->out.dst = iov->iov_base;
+        z->out.size = iov->iov_len;
+        z->out.pos = 0;
+
+        ret = ZSTD_decompressStream(z->zds, &z->out, &z->in);
+        if (ZSTD_isError(ret)) {
+            error_setg(errp, "multifd %d: decompressStream returned %s",
+                       p->id, ZSTD_getErrorName(ret));
+            return ret;
+        }
+        out_size += iov->iov_len;
+    }
+    if (out_size != expected_size) {
+        error_setg(errp, "multifd %d: packet size received %d size expected %d",
+                   p->id, out_size, expected_size);
+        return -1;
+    }
+    return 0;
+}
+
+static MultiFDMethods multifd_zstd_ops = {
+    .send_setup = zstd_send_setup,
+    .send_cleanup = zstd_send_cleanup,
+    .send_prepare = zstd_send_prepare,
+    .send_write = zstd_send_write,
+    .recv_setup = zstd_recv_setup,
+    .recv_cleanup = zstd_recv_cleanup,
+    .recv_pages = zstd_recv_pages
+};
+
+static void multifd_zstd_register(void)
+{
+    multifd_register_ops(MULTIFD_METHOD_ZSTD, &multifd_zstd_ops);
+}
+
+migration_init(multifd_zstd_register);
diff --git a/migration/multifd.h b/migration/multifd.h
index 3fa5132f1d..621db316c1 100644
--- a/migration/multifd.h
+++ b/migration/multifd.h
@@ -30,6 +30,7 @@ int multifd_queue_page(QEMUFile *f, RAMBlock *block, ram_addr_t offset);
 #define MULTIFD_FLAG_METHOD_MASK (7 << 1)
 #define MULTIFD_FLAG_NOCOMP (1 << 1)
 #define MULTIFD_FLAG_ZLIB (2 << 1)
+#define MULTIFD_FLAG_ZSTD (3 << 1)
 
 /* This value needs to be a multiple of qemu_target_page_size() */
 #define MULTIFD_PACKET_SIZE (512 * 1024)
@@ -163,6 +164,5 @@ typedef struct {
 } MultiFDMethods;
 
 void multifd_register_ops(int method, MultiFDMethods *ops);
-
 #endif
 
diff --git a/migration/ram.c b/migration/ram.c
index 73a141bb60..0ef68798d2 100644
--- a/migration/ram.c
+++ b/migration/ram.c
@@ -28,7 +28,6 @@
 
 #include "qemu/osdep.h"
 #include "cpu.h"
-#include <zlib.h>
 #include "qemu/cutils.h"
 #include "qemu/bitops.h"
 #include "qemu/bitmap.h"
diff --git a/qapi/migration.json b/qapi/migration.json
index bb5cb6b4f4..8ccec7fa79 100644
--- a/qapi/migration.json
+++ b/qapi/migration.json
@@ -495,12 +495,14 @@
 #
 # @none: no compression.
 # @zlib: use zlib compression method.
+# @zstd: use zstd compression method.
 #
 # Since: 5.0
 #
 ##
 { 'enum': 'MultiFDMethod',
-  'data': [ 'none', 'zlib' ] }
+  'data': [ 'none', 'zlib',
+            { 'name': 'zstd', 'if': 'defined(CONFIG_ZSTD)' } ] }
 
 ##
 # @MigrationParameter:
diff --git a/tests/qtest/migration-test.c b/tests/qtest/migration-test.c
index 8effed205d..ec9be28bc9 100644
--- a/tests/qtest/migration-test.c
+++ b/tests/qtest/migration-test.c
@@ -1318,6 +1318,13 @@ static void test_multifd_tcp_zlib(void)
     test_multifd_tcp("zlib");
 }
 
+#ifdef CONFIG_ZSTD
+static void test_multifd_tcp_zstd(void)
+{
+    test_multifd_tcp("zstd");
+}
+#endif
+
 /*
  * This test does:
  *  source               target
@@ -1481,6 +1488,9 @@ int main(int argc, char **argv)
     qtest_add_func("/migration/multifd/tcp/none", test_multifd_tcp_none);
     qtest_add_func("/migration/multifd/tcp/cancel", test_multifd_tcp_cancel);
     qtest_add_func("/migration/multifd/tcp/zlib", test_multifd_tcp_zlib);
+#ifdef CONFIG_ZSTD
+    qtest_add_func("/migration/multifd/tcp/zstd", test_multifd_tcp_zstd);
+#endif
 
     ret = g_test_run();
 
-- 
2.24.1