This will allow us to reduce the number of system calls on the next patch.
Signed-off-by: Juan Quintela <quint...@redhat.com>
---
migration/multifd.h | 8 ++++++--
migration/multifd.c | 34 ++++++++++++++++++++++++----------
2 files changed, 30 insertions(+), 12 deletions(-)
diff --git a/migration/multifd.h b/migration/multifd.h
index e57adc783b..c3f18af364 100644
--- a/migration/multifd.h
+++ b/migration/multifd.h
@@ -62,8 +62,6 @@ typedef struct {
uint64_t packet_num;
/* offset of each page */
ram_addr_t *offset;
- /* pointer to each page */
- struct iovec *iov;
RAMBlock *block;
} MultiFDPages_t;
@@ -110,6 +108,10 @@ typedef struct {
uint64_t num_pages;
/* syncs main thread and channels */
QemuSemaphore sem_sync;
+ /* buffers to send */
+ struct iovec *iov;
+ /* number of iovs used */
+ uint32_t iovs_num;
/* used for compression methods */
void *data;
} MultiFDSendParams;
@@ -149,6 +151,8 @@ typedef struct {
uint64_t num_pages;
/* syncs main thread and channels */
QemuSemaphore sem_sync;
+ /* buffers to recv */
+ struct iovec *iov;
/* used for de-compression methods */
void *data;
} MultiFDRecvParams;
diff --git a/migration/multifd.c b/migration/multifd.c
index 4d62850258..f75bd3c188 100644
--- a/migration/multifd.c
+++ b/migration/multifd.c
@@ -86,7 +86,16 @@ static void nocomp_send_cleanup(MultiFDSendParams *p, Error
**errp)
*/
static int nocomp_send_prepare(MultiFDSendParams *p, Error **errp)
{
- p->next_packet_size = p->pages->num * qemu_target_page_size();
+ MultiFDPages_t *pages = p->pages;
+ size_t page_size = qemu_target_page_size();
+
+ for (int i = 0; i < p->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->pages->num * page_size;
p->flags |= MULTIFD_FLAG_NOCOMP;
return 0;
}
@@ -104,7 +113,7 @@ static int nocomp_send_prepare(MultiFDSendParams *p, Error
**errp)
*/
static int nocomp_send_write(MultiFDSendParams *p, uint32_t used, Error **errp)
{
- return qio_channel_writev_all(p->c, p->pages->iov, used, errp);
+ return qio_channel_writev_all(p->c, p->iov, p->iovs_num, errp);
}
/**
@@ -146,13 +155,18 @@ static void nocomp_recv_cleanup(MultiFDRecvParams *p)
static int nocomp_recv_pages(MultiFDRecvParams *p, Error **errp)
{
uint32_t flags = p->flags & MULTIFD_FLAG_COMPRESSION_MASK;
+ size_t page_size = qemu_target_page_size();
if (flags != MULTIFD_FLAG_NOCOMP) {
error_setg(errp, "multifd %u: flags received %x flags expected %x",
p->id, flags, MULTIFD_FLAG_NOCOMP);
return -1;
}
- return qio_channel_readv_all(p->c, p->pages->iov, p->pages->num, errp);
+ for (int i = 0; i < p->pages->num; i++) {
+ p->iov[i].iov_base = p->pages->block->host + p->pages->offset[i];
+ p->iov[i].iov_len = page_size;
+ }
+ return qio_channel_readv_all(p->c, p->iov, p->pages->num, errp);
}
static MultiFDMethods multifd_nocomp_ops = {
@@ -242,7 +256,6 @@ static MultiFDPages_t *multifd_pages_init(size_t size)
MultiFDPages_t *pages = g_new0(MultiFDPages_t, 1);
pages->allocated = size;
- pages->iov = g_new0(struct iovec, size);
pages->offset = g_new0(ram_addr_t, size);
return pages;
@@ -254,8 +267,6 @@ static void multifd_pages_clear(MultiFDPages_t *pages)
pages->allocated = 0;
pages->packet_num = 0;
pages->block = NULL;
- g_free(pages->iov);
- pages->iov = NULL;
g_free(pages->offset);
pages->offset = NULL;
g_free(pages);
@@ -365,8 +376,6 @@ static int multifd_recv_unfill_packet(MultiFDRecvParams *p,
Error **errp)
return -1;
}
p->pages->offset[i] = offset;
- p->pages->iov[i].iov_base = block->host + offset;
- p->pages->iov[i].iov_len = page_size;
}
return 0;
@@ -470,8 +479,6 @@ int multifd_queue_page(QEMUFile *f, RAMBlock *block,
ram_addr_t offset)
if (pages->block == block) {
pages->offset[pages->num] = offset;
- pages->iov[pages->num].iov_base = block->host + offset;
- pages->iov[pages->num].iov_len = qemu_target_page_size();
pages->num++;
if (pages->num < pages->allocated) {
@@ -567,6 +574,8 @@ void multifd_save_cleanup(void)
p->packet_len = 0;
g_free(p->packet);
p->packet = NULL;
+ g_free(p->iov);
+ p->iov = NULL;
multifd_send_state->ops->send_cleanup(p, &local_err);
if (local_err) {
migrate_set_error(migrate_get_current(), local_err);
@@ -654,6 +663,7 @@ static void *multifd_send_thread(void *opaque)
uint32_t used = p->pages->num;
uint64_t packet_num = p->packet_num;
uint32_t flags = p->flags;
+ p->iovs_num = 0;
if (used) {
ret = multifd_send_state->ops->send_prepare(p, &local_err);
@@ -922,6 +932,7 @@ int multifd_save_setup(Error **errp)
p->packet->version = cpu_to_be32(MULTIFD_VERSION);
p->name = g_strdup_printf("multifdsend_%d", i);
p->tls_hostname = g_strdup(s->hostname);
+ p->iov = g_new0(struct iovec, page_count);
socket_send_channel_create(multifd_new_send_channel_async, p);
}
@@ -1021,6 +1032,8 @@ int multifd_load_cleanup(Error **errp)
p->packet_len = 0;
g_free(p->packet);
p->packet = NULL;
+ g_free(p->iov);
+ p->iov = NULL;
multifd_recv_state->ops->recv_cleanup(p);
}
qemu_sem_destroy(&multifd_recv_state->sem_sync);
@@ -1161,6 +1174,7 @@ int multifd_load_setup(Error **errp)
+ sizeof(uint64_t) * page_count;
p->packet = g_malloc0(p->packet_len);
p->name = g_strdup_printf("multifdrecv_%d", i);
+ p->iov = g_new0(struct iovec, page_count);
}
for (i = 0; i < thread_count; i++) {
--
2.34.1
