migration/rdma: Unfold ram_control_before_iterate()

Once there:
- Remove unused data parameter
- unfold it in its callers.
- change all callers to call qemu_rdma_registration_start()
- We need to call QIO_CHANNEL_RDMA() after we check for migrate_rdma()

Reviewed-by: Li Zhijian <lizhijian@fujitsu.com>
Reviewed-by: Fabiano Rosas <farosas@suse.de>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Message-ID: <20231011203527.9061-3-quintela@redhat.com>

migration/qemu-file.c

@@ -32,6 +32,7 @@
 #include "trace.h"
 #include "options.h"
 #include "qapi/error.h"
+#include "rdma.h"
 
 #define IO_BUF_SIZE 32768
 #define MAX_IOV_SIZE MIN_CONST(IOV_MAX, 64)
@@ -297,18 +298,6 @@ void qemu_fflush(QEMUFile *f)
     f->iovcnt = 0;
 }
 
-void ram_control_before_iterate(QEMUFile *f, uint64_t flags)
-{
-    int ret = 0;
-
-    if (f->hooks && f->hooks->before_ram_iterate) {
-        ret = f->hooks->before_ram_iterate(f, flags, NULL);
-        if (ret < 0) {
-            qemu_file_set_error(f, ret);
-        }
-    }
-}
-
 void ram_control_after_iterate(QEMUFile *f, uint64_t flags)
 {
     int ret = 0;

migration/qemu-file.h

@@ -55,7 +55,6 @@ typedef int (QEMURamSaveFunc)(QEMUFile *f,
                               size_t size);
 
 typedef struct QEMUFileHooks {
-    QEMURamHookFunc *before_ram_iterate;
     QEMURamHookFunc *after_ram_iterate;
     QEMURamHookFunc *hook_ram_load;
     QEMURamSaveFunc *save_page;
@@ -127,7 +126,6 @@ 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);
 void ram_control_load_hook(QEMUFile *f, uint64_t flags, void *data);
 

migration/ram.c

@@ -59,6 +59,7 @@
 #include "qemu/iov.h"
 #include "multifd.h"
 #include "sysemu/runstate.h"
+#include "rdma.h"
 #include "options.h"
 #include "sysemu/dirtylimit.h"
 #include "sysemu/kvm.h"
@@ -3060,7 +3061,10 @@ static int ram_save_setup(QEMUFile *f, void *opaque)
         }
     }
 
-    ram_control_before_iterate(f, RAM_CONTROL_SETUP);
+    ret = qemu_rdma_registration_start(f, RAM_CONTROL_SETUP);
+    if (ret < 0) {
+        qemu_file_set_error(f, ret);
+    }
     ram_control_after_iterate(f, RAM_CONTROL_SETUP);
 
     migration_ops = g_malloc0(sizeof(MigrationOps));
@@ -3123,7 +3127,10 @@ static int ram_save_iterate(QEMUFile *f, void *opaque)
         /* Read version before ram_list.blocks */
         smp_rmb();
 
-        ram_control_before_iterate(f, RAM_CONTROL_ROUND);
+        ret = qemu_rdma_registration_start(f, RAM_CONTROL_ROUND);
+        if (ret < 0) {
+            qemu_file_set_error(f, ret);
+        }
 
         t0 = qemu_clock_get_ns(QEMU_CLOCK_REALTIME);
         i = 0;
@@ -3228,7 +3235,10 @@ static int ram_save_complete(QEMUFile *f, void *opaque)
             migration_bitmap_sync_precopy(rs, true);
         }
 
-        ram_control_before_iterate(f, RAM_CONTROL_FINISH);
+        ret = qemu_rdma_registration_start(f, RAM_CONTROL_FINISH);
+        if (ret < 0) {
+            qemu_file_set_error(f, ret);
+        }
 
         /* try transferring iterative blocks of memory */
 

migration/rdma.c

@@ -3850,18 +3850,15 @@ static int rdma_load_hook(QEMUFile *f, uint64_t flags, void *data)
     }
 }
 
-static int qemu_rdma_registration_start(QEMUFile *f,
-                                        uint64_t flags, void *data)
+int qemu_rdma_registration_start(QEMUFile *f, uint64_t flags)
 {
-    QIOChannelRDMA *rioc = QIO_CHANNEL_RDMA(qemu_file_get_ioc(f));
-    RDMAContext *rdma;
-
-    if (migration_in_postcopy()) {
+    if (!migrate_rdma() || migration_in_postcopy()) {
         return 0;
     }
 
+    QIOChannelRDMA *rioc = QIO_CHANNEL_RDMA(qemu_file_get_ioc(f));
     RCU_READ_LOCK_GUARD();
-    rdma = qatomic_rcu_read(&rioc->rdmaout);
+    RDMAContext *rdma = qatomic_rcu_read(&rioc->rdmaout);
     if (!rdma) {
         return -1;
     }
@@ -4002,7 +3999,6 @@ static const QEMUFileHooks rdma_read_hooks = {
 };
 
 static const QEMUFileHooks rdma_write_hooks = {
-    .before_ram_iterate = qemu_rdma_registration_start,
     .after_ram_iterate  = qemu_rdma_registration_stop,
     .save_page          = qemu_rdma_save_page,
 };

migration/rdma.h

@@ -22,4 +22,11 @@ void rdma_start_outgoing_migration(void *opaque, const char *host_port,
 
 void rdma_start_incoming_migration(const char *host_port, Error **errp);
 
+
+#ifdef CONFIG_RDMA
+int qemu_rdma_registration_start(QEMUFile *f, uint64_t flags);
+#else
+static inline
+int qemu_rdma_registration_start(QEMUFile *f, uint64_t flags) { return 0; }
+#endif
 #endif