diff options
| author | Juan Quintela <quintela@redhat.com> | 2019-02-20 12:44:07 +0100 |
|---|---|---|
| committer | Juan Quintela <quintela@redhat.com> | 2019-03-25 18:13:42 +0100 |
| commit | 7ed379b286dc6d3942ae851bdfa87b45b99ae9ff (patch) | |
| tree | 5e093cf361a2d8f373081772eba8e1fee92670e7 | |
| parent | efd1a1d6407f73565cf3b4089a2baa4bad0650f8 (diff) | |
multifd: Be flexible about packet size
This way we can change the packet size in the future and everything
will work. We choose an arbitrary big number (100 times configured
size) as a limit about how big we will reallocate.
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
| -rw-r--r-- | migration/ram.c | 24 |
1 files changed, 18 insertions, 6 deletions
diff --git a/migration/ram.c b/migration/ram.c index 454d3eb539..77c1878292 100644 --- a/migration/ram.c +++ b/migration/ram.c @@ -786,13 +786,13 @@ static void multifd_pages_clear(MultiFDPages_t *pages) static void multifd_send_fill_packet(MultiFDSendParams *p) { MultiFDPacket_t *packet = p->packet; - uint32_t page_count = MULTIFD_PACKET_SIZE / qemu_target_page_size(); + uint32_t page_max = MULTIFD_PACKET_SIZE / qemu_target_page_size(); int i; packet->magic = cpu_to_be32(MULTIFD_MAGIC); packet->version = cpu_to_be32(MULTIFD_VERSION); packet->flags = cpu_to_be32(p->flags); - packet->pages_alloc = cpu_to_be32(page_count); + packet->pages_alloc = cpu_to_be32(page_max); packet->pages_used = cpu_to_be32(p->pages->used); packet->next_packet_size = cpu_to_be32(p->next_packet_size); packet->packet_num = cpu_to_be64(p->packet_num); @@ -809,7 +809,7 @@ static void multifd_send_fill_packet(MultiFDSendParams *p) static int multifd_recv_unfill_packet(MultiFDRecvParams *p, Error **errp) { MultiFDPacket_t *packet = p->packet; - uint32_t page_count = MULTIFD_PACKET_SIZE / qemu_target_page_size(); + uint32_t pages_max = MULTIFD_PACKET_SIZE / qemu_target_page_size(); RAMBlock *block; int i; @@ -832,12 +832,24 @@ static int multifd_recv_unfill_packet(MultiFDRecvParams *p, Error **errp) p->flags = be32_to_cpu(packet->flags); packet->pages_alloc = be32_to_cpu(packet->pages_alloc); - if (packet->pages_alloc > page_count) { + /* + * If we recevied a packet that is 100 times bigger than expected + * just stop migration. It is a magic number. + */ + if (packet->pages_alloc > pages_max * 100) { error_setg(errp, "multifd: received packet " - "with size %d and expected maximum size %d", - packet->pages_alloc, page_count) ; + "with size %d and expected a maximum size of %d", + packet->pages_alloc, pages_max * 100) ; return -1; } + /* + * We received a packet that is bigger than expected but inside + * reasonable limits (see previous comment). Just reallocate. + */ + if (packet->pages_alloc > p->pages->allocated) { + multifd_pages_clear(p->pages); + multifd_pages_init(packet->pages_alloc); + } p->pages->used = be32_to_cpu(packet->pages_used); if (p->pages->used > packet->pages_alloc) { |