[RFC,1/7] migration: Drop stale comment for multifd zero copy

Commit Message

Peter Xu Oct. 22, 2023, 8:12 p.m. UTC

We've already done that with multifd_flush_after_each_section, for multifd
in general.  Drop the stale "TODO-like" comment.

Signed-off-by: Peter Xu <[e-mail]>
---
 migration/multifd.c | 11 -----------
 1 file changed, 11 deletions(-)

Comments

Fabiano Rosas Oct. 23, 2023, 2:16 p.m. UTC | #1

Peter Xu <[e-mail]> writes:

> We've already done that with multifd_flush_after_each_section, for multifd
> in general.  Drop the stale "TODO-like" comment.
>
> Signed-off-by: Peter Xu <[e-mail]>

Reviewed-by: Fabiano Rosas <[e-mail]>

Patch

diff --git a/migration/multifd.c b/migration/multifd.c
index 1fe53d3b98..c8bdd88041 100644
--- a/migration/multifd.c
+++ b/migration/multifd.c
@@ -600,17 +600,6 @@  int multifd_send_sync_main(QEMUFile *f)
         }
     }
 
-    /*
-     * When using zero-copy, it's necessary to flush the pages before any of
-     * the pages can be sent again, so we'll make sure the new version of the
-     * pages will always arrive _later_ than the old pages.
-     *
-     * Currently we achieve this by flushing the zero-page requested writes
-     * per ram iteration, but in the future we could potentially optimize it
-     * to be less frequent, e.g. only after we finished one whole scanning of
-     * all the dirty bitmaps.
-     */
-
     flush_zero_copy = migrate_zero_copy_send();
 
     for (i = 0; i < migrate_multifd_channels(); i++) {