All pages which are going to be migrated are first added to MultiFDSendParams::MultiFDPages_t::offset array by the main migration thread and are subsequently copied to MultiFDSendParams::normal by the multifd thread. This is really unnecessary as the MultiFDPages_t is guaranteed to be stable since its mutex is being held. Additionally, this somewhat simplifies the code as the migration pages are now kept in only 1 place during send, also the name 'offset' coupled with the context it's being used - usually added to the host pages makes it obvious that this is an offset.
With this change normal/normal_num are no longer used in the multifd send path. Signed-off-by: Nikolay Borisov <nbori...@suse.com> --- migration/multifd-zlib.c | 6 +++--- migration/multifd-zstd.c | 6 +++--- migration/multifd.c | 25 ++++++++++--------------- 3 files changed, 16 insertions(+), 21 deletions(-) diff --git a/migration/multifd-zlib.c b/migration/multifd-zlib.c index 18213a951302..363b64e95922 100644 --- a/migration/multifd-zlib.c +++ b/migration/multifd-zlib.c @@ -122,11 +122,11 @@ static int zlib_send_prepare(MultiFDSendParams *p, Error **errp) int ret; uint32_t i; - for (i = 0; i < p->normal_num; i++) { + for (i = 0; i < p->pages->num; i++) { uint32_t available = z->zbuff_len - out_size; int flush = Z_NO_FLUSH; - if (i == p->normal_num - 1) { + if (i == p->pages->num - 1) { flush = Z_SYNC_FLUSH; } @@ -135,7 +135,7 @@ static int zlib_send_prepare(MultiFDSendParams *p, Error **errp) * with compression. zlib does not guarantee that this is safe, * therefore copy the page before calling deflate(). */ - memcpy(z->buf, p->pages->block->host + p->normal[i], page_size); + memcpy(z->buf, p->pages->block->host + p->pages->offset[i], page_size); zs->avail_in = page_size; zs->next_in = z->buf; diff --git a/migration/multifd-zstd.c b/migration/multifd-zstd.c index d788d309f22e..4daec8366727 100644 --- a/migration/multifd-zstd.c +++ b/migration/multifd-zstd.c @@ -121,13 +121,13 @@ static int zstd_send_prepare(MultiFDSendParams *p, Error **errp) z->out.size = z->zbuff_len; z->out.pos = 0; - for (i = 0; i < p->normal_num; i++) { + for (i = 0; i < p->pages->num; i++) { ZSTD_EndDirective flush = ZSTD_e_continue; - if (i == p->normal_num - 1) { + if (i == p->pages->num - 1) { flush = ZSTD_e_flush; } - z->in.src = p->pages->block->host + p->normal[i]; + z->in.src = p->pages->block->host + p->pages->offset[i]; z->in.size = page_size; z->in.pos = 0; diff --git a/migration/multifd.c b/migration/multifd.c index 586ddc9d657a..d70662406490 100644 --- a/migration/multifd.c +++ b/migration/multifd.c @@ -89,13 +89,13 @@ static int nocomp_send_prepare(MultiFDSendParams *p, Error **errp) MultiFDPages_t *pages = p->pages; size_t page_size = qemu_target_page_size(); - for (int i = 0; i < p->normal_num; i++) { - p->iov[p->iovs_num].iov_base = pages->block->host + p->normal[i]; + for (int i = 0; i < pages->num; i++) { + p->iov[p->iovs_num].iov_base = pages->block->host + pages->offset[i]; p->iov[p->iovs_num].iov_len = page_size; p->iovs_num++; } - p->next_packet_size = p->normal_num * page_size; + p->next_packet_size = pages->num * page_size; p->flags |= MULTIFD_FLAG_NOCOMP; return 0; } @@ -262,7 +262,7 @@ static void multifd_send_fill_packet(MultiFDSendParams *p) packet->flags = cpu_to_be32(p->flags); packet->pages_alloc = cpu_to_be32(p->pages->allocated); - packet->normal_pages = cpu_to_be32(p->normal_num); + packet->normal_pages = cpu_to_be32(p->pages->num); packet->next_packet_size = cpu_to_be32(p->next_packet_size); packet->packet_num = cpu_to_be64(p->packet_num); @@ -270,9 +270,9 @@ static void multifd_send_fill_packet(MultiFDSendParams *p) strncpy(packet->ramblock, p->pages->block->idstr, 256); } - for (i = 0; i < p->normal_num; i++) { + for (i = 0; i < p->pages->num; i++) { /* there are architectures where ram_addr_t is 32 bit */ - uint64_t temp = p->normal[i]; + uint64_t temp = p->pages->offset[i]; packet->offset[i] = cpu_to_be64(temp); } @@ -668,7 +668,7 @@ static void *multifd_send_thread(void *opaque) if (p->pending_job) { uint64_t packet_num = p->packet_num; uint32_t flags = p->flags; - p->normal_num = 0; + uint32_t num_pages = p->pages->num; if (use_zero_copy_send) { p->iovs_num = 0; @@ -676,12 +676,7 @@ static void *multifd_send_thread(void *opaque) p->iovs_num = 1; } - for (int i = 0; i < p->pages->num; i++) { - p->normal[p->normal_num] = p->pages->offset[i]; - p->normal_num++; - } - - if (p->normal_num) { + if (num_pages) { ret = multifd_send_state->ops->send_prepare(p, &local_err); if (ret != 0) { qemu_mutex_unlock(&p->mutex); @@ -691,12 +686,12 @@ static void *multifd_send_thread(void *opaque) multifd_send_fill_packet(p); p->flags = 0; p->num_packets++; - p->total_normal_pages += p->normal_num; + p->total_normal_pages += num_pages; p->pages->num = 0; p->pages->block = NULL; qemu_mutex_unlock(&p->mutex); - trace_multifd_send(p->id, packet_num, p->normal_num, flags, + trace_multifd_send(p->id, packet_num, num_pages, flags, p->next_packet_size); if (use_zero_copy_send) { -- 2.25.1