From 86be843cee1157f605820fc02a8cad8a00fe09e9 Mon Sep 17 00:00:00 2001 From: "Dr. David Alan Gilbert" Date: Fri, 17 Jun 2016 14:39:22 +0200 Subject: [PATCH 01/33] Postcopy: Avoid 0 length discards RH-Author: Dr. David Alan Gilbert Message-id: <1466174367-11047-2-git-send-email-dgilbert@redhat.com> Patchwork-id: 70659 O-Subject: [RHEL-7.3 qemu-kvm-rhev PATCH 1/6] Postcopy: Avoid 0 length discards Bugzilla: 1347256 RH-Acked-by: Juan Quintela RH-Acked-by: John Snow RH-Acked-by: Amit Shah From: "Dr. David Alan Gilbert" The discard code in migration/ram.c would send request for zero length discards in the case where no discards were needed. It doesn't appear to have had any bad effect. Signed-off-by: Dr. David Alan Gilbert Reviewed-by: Denis V. Lunev Message-id: 1465816605-29488-2-git-send-email-dgilbert@redhat.com Message-Id: <1465816605-29488-2-git-send-email-dgilbert@redhat.com> Signed-off-by: Amit Shah (cherry picked from commit d688c62d0928c46437b6b95848922398674538c8) Signed-off-by: Miroslav Rezanina --- migration/ram.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/migration/ram.c b/migration/ram.c index 3f05738..e96c2af 100644 --- a/migration/ram.c +++ b/migration/ram.c @@ -1557,7 +1557,9 @@ static int postcopy_send_discard_bm_ram(MigrationState *ms, } else { discard_length = zero - one; } - postcopy_discard_send_range(ms, pds, one, discard_length); + if (discard_length) { + postcopy_discard_send_range(ms, pds, one, discard_length); + } current = one + discard_length; } else { current = one; -- 1.8.3.1