migration/multifd: Postpone reset of MultiFDPages_t

Now we reset MultiFDPages_t object in the multifd sender thread in the
middle of the sending job.  That's not necessary, because the "*pages"
struct will not be reused anyway until pending_job is cleared.

Move that to the end after the job is completed, provide a helper to reset
a "*pages" object.  Use that same helper when free the object too.

This prepares us to keep using p->pages in the follow up patches, where we
may drop p->normal[].

Reviewed-by: Fabiano Rosas <farosas@suse.de>
Link: https://lore.kernel.org/r/20240202102857.110210-5-peterx@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>
This commit is contained in:
Peter Xu 2024-02-02 18:28:38 +08:00
parent 15f3f21d59
commit 836eca47f6

View File

@ -172,6 +172,17 @@ void multifd_register_ops(int method, MultiFDMethods *ops)
multifd_ops[method] = ops;
}
/* Reset a MultiFDPages_t* object for the next use */
static void multifd_pages_reset(MultiFDPages_t *pages)
{
/*
* We don't need to touch offset[] array, because it will be
* overwritten later when reused.
*/
pages->num = 0;
pages->block = NULL;
}
static int multifd_send_initial_packet(MultiFDSendParams *p, Error **errp)
{
MultiFDInit_t msg = {};
@ -248,9 +259,8 @@ static MultiFDPages_t *multifd_pages_init(uint32_t n)
static void multifd_pages_clear(MultiFDPages_t *pages)
{
pages->num = 0;
multifd_pages_reset(pages);
pages->allocated = 0;
pages->block = NULL;
g_free(pages->offset);
pages->offset = NULL;
g_free(pages);
@ -704,8 +714,6 @@ static void *multifd_send_thread(void *opaque)
p->flags = 0;
p->num_packets++;
p->total_normal_pages += p->normal_num;
p->pages->num = 0;
p->pages->block = NULL;
qemu_mutex_unlock(&p->mutex);
trace_multifd_send(p->id, packet_num, p->normal_num, flags,
@ -732,6 +740,8 @@ static void *multifd_send_thread(void *opaque)
stat64_add(&mig_stats.multifd_bytes,
p->next_packet_size + p->packet_len);
multifd_pages_reset(p->pages);
p->next_packet_size = 0;
qemu_mutex_lock(&p->mutex);
p->pending_job--;