migration: We set the rate_limit by a second

That the implementation does the check every 100 milliseconds is an implementation detail that shouldn't be seen on the interfaz. Notice that all callers of qemu_file_set_rate_limit() used the division or pass 0, so this change is a NOP. Signed-off-by: Juan Quintela <quintela@redhat.com> Reviewed-by: Cédric Le Goater <clg@kaod.org> Message-Id: <20230508130909.65420-4-quintela@redhat.com>
qemu · May 15, 2023 · 9d3ebbe · 9d3ebbe
1 parent 52d01d4
commit 9d3ebbe
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Showing 3 changed files with 10 additions and 7 deletions.
diff --git a/migration/migration.c b/migration/migration.c
@@ -2140,7 +2140,7 @@ static int postcopy_start(MigrationState *ms)
      * will notice we're in POSTCOPY_ACTIVE and not actually
      * wrap their state up here
      */
-    qemu_file_set_rate_limit(ms->to_dst_file, bandwidth / XFER_LIMIT_RATIO);
+    qemu_file_set_rate_limit(ms->to_dst_file, bandwidth);
     if (migrate_postcopy_ram()) {
         /* Ping just for debugging, helps line traces up */
         qemu_savevm_send_ping(ms->to_dst_file, 2);
@@ -3231,11 +3231,10 @@ void migrate_fd_connect(MigrationState *s, Error *error_in)
 
     if (resume) {
         /* This is a resumed migration */
-        rate_limit = migrate_max_postcopy_bandwidth() /
-            XFER_LIMIT_RATIO;
+        rate_limit = migrate_max_postcopy_bandwidth();
     } else {
         /* This is a fresh new migration */
-        rate_limit = migrate_max_bandwidth() / XFER_LIMIT_RATIO;
+        rate_limit = migrate_max_bandwidth();
 
         /* Notify before starting migration thread */
         notifier_list_notify(&migration_state_notifiers, s);

diff --git a/migration/options.c b/migration/options.c
@@ -1243,7 +1243,7 @@ static void migrate_params_apply(MigrateSetParameters *params, Error **errp)
         s->parameters.max_bandwidth = params->max_bandwidth;
         if (s->to_dst_file && !migration_in_postcopy()) {
             qemu_file_set_rate_limit(s->to_dst_file,
-                                s->parameters.max_bandwidth / XFER_LIMIT_RATIO);
+                                s->parameters.max_bandwidth);
         }
     }
 
@@ -1273,7 +1273,7 @@ static void migrate_params_apply(MigrateSetParameters *params, Error **errp)
         s->parameters.max_postcopy_bandwidth = params->max_postcopy_bandwidth;
         if (s->to_dst_file && migration_in_postcopy()) {
             qemu_file_set_rate_limit(s->to_dst_file,
-                    s->parameters.max_postcopy_bandwidth / XFER_LIMIT_RATIO);
+                    s->parameters.max_postcopy_bandwidth);
         }
     }
     if (params->has_max_cpu_throttle) {

diff --git a/migration/qemu-file.c b/migration/qemu-file.c
@@ -29,6 +29,7 @@
 #include "migration.h"
 #include "qemu-file.h"
 #include "trace.h"
+#include "options.h"
 #include "qapi/error.h"
 
 #define IO_BUF_SIZE 32768
@@ -744,7 +745,10 @@ int64_t qemu_file_get_rate_limit(QEMUFile *f)
 
 void qemu_file_set_rate_limit(QEMUFile *f, int64_t limit)
 {
-    f->rate_limit_max = limit;
+    /*
+     * 'limit' is per second.  But we check it each 100 miliseconds.
+     */
+    f->rate_limit_max = limit / XFER_LIMIT_RATIO;
 }
 
 void qemu_file_reset_rate_limit(QEMUFile *f)