[PULL 02/34] migration/multifd: Drop stale comment for multifd zero copy

peterx@redhat.com posted 34 patches 9 months, 3 weeks ago
Maintainers: "Alex Bennée" <alex.bennee@linaro.org>, "Philippe Mathieu-Daudé" <philmd@linaro.org>, Thomas Huth <thuth@redhat.com>, Wainer dos Santos Moschetta <wainersm@redhat.com>, Beraldo Leal <bleal@redhat.com>, Paolo Bonzini <pbonzini@redhat.com>, Peter Xu <peterx@redhat.com>, Fabiano Rosas <farosas@suse.de>, Laurent Vivier <lvivier@redhat.com>
[PULL 02/34] migration/multifd: Drop stale comment for multifd zero copy
Posted by peterx@redhat.com 9 months, 3 weeks ago
From: Peter Xu <peterx@redhat.com>

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

Reviewed-by: Fabiano Rosas <farosas@suse.de>
Link: https://lore.kernel.org/r/20240202102857.110210-2-peterx@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>
---
 migration/multifd.c | 11 -----------
 1 file changed, 11 deletions(-)

diff --git a/migration/multifd.c b/migration/multifd.c
index 25cbc6dc6b..eee2586770 100644
--- a/migration/multifd.c
+++ b/migration/multifd.c
@@ -598,17 +598,6 @@ int multifd_send_sync_main(void)
         }
     }
 
-    /*
-     * 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++) {
-- 
2.43.0