[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
[PATCH v7 08/13] multifd: Prepare to send a packet without the mutex hel
From: |
Juan Quintela |
Subject: |
[PATCH v7 08/13] multifd: Prepare to send a packet without the mutex held |
Date: |
Tue, 31 May 2022 12:43:13 +0200 |
We do the send_prepare() and the fill of the head packet without the
mutex held. It will help a lot for compression and later in the
series for zero pages.
Notice that we can use p->pages without holding p->mutex because
p->pending_job == 1.
Signed-off-by: Juan Quintela <quintela@redhat.com>
---
migration/multifd.h | 2 ++
migration/multifd.c | 11 ++++++-----
2 files changed, 8 insertions(+), 5 deletions(-)
diff --git a/migration/multifd.h b/migration/multifd.h
index af8ce8921d..d48597a1ea 100644
--- a/migration/multifd.h
+++ b/migration/multifd.h
@@ -109,7 +109,9 @@ typedef struct {
/* array of pages to sent.
* The owner of 'pages' depends of 'pending_job' value:
* pending_job == 0 -> migration_thread can use it.
+ * No need for mutex lock.
* pending_job != 0 -> multifd_channel can use it.
+ * No need for mutex lock.
*/
MultiFDPages_t *pages;
diff --git a/migration/multifd.c b/migration/multifd.c
index 69b9d7cf98..056599cbaf 100644
--- a/migration/multifd.c
+++ b/migration/multifd.c
@@ -661,6 +661,8 @@ static void *multifd_send_thread(void *opaque)
p->flags |= MULTIFD_FLAG_SYNC;
p->sync_needed = false;
}
+ qemu_mutex_unlock(&p->mutex);
+
p->normal_num = 0;
if (use_zero_copy_send) {
@@ -682,11 +684,6 @@ static void *multifd_send_thread(void *opaque)
}
}
multifd_send_fill_packet(p);
- 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, p->flags,
p->next_packet_size);
@@ -711,6 +708,10 @@ static void *multifd_send_thread(void *opaque)
}
qemu_mutex_lock(&p->mutex);
+ p->num_packets++;
+ p->total_normal_pages += p->normal_num;
+ p->pages->num = 0;
+ p->pages->block = NULL;
p->sent_bytes += p->packet_len;;
p->sent_bytes += p->next_packet_size;
p->pending_job--;
--
2.35.3
- [PATCH v7 00/13] Migration: Transmit and detect zero pages in the multifd threads, Juan Quintela, 2022/05/31
- [PATCH v7 02/13] multifd: Create page_size fields into both MultiFD{Recv, Send}Params, Juan Quintela, 2022/05/31
- [PATCH v7 01/13] multifd: Document the locking of MultiFD{Send/Recv}Params, Juan Quintela, 2022/05/31
- [PATCH v7 03/13] multifd: Create page_count fields into both MultiFD{Recv, Send}Params, Juan Quintela, 2022/05/31
- [PATCH v7 04/13] migration: Export ram_transferred_ram(), Juan Quintela, 2022/05/31
- [PATCH v7 05/13] multifd: Count the number of bytes sent correctly, Juan Quintela, 2022/05/31
- [PATCH v7 06/13] migration: Make ram_save_target_page() a pointer, Juan Quintela, 2022/05/31
- [PATCH v7 07/13] multifd: Make flags field thread local, Juan Quintela, 2022/05/31
- [PATCH v7 08/13] multifd: Prepare to send a packet without the mutex held,
Juan Quintela <=
- [PATCH v7 09/13] multifd: Add property to enable/disable zero_page, Juan Quintela, 2022/05/31
- [PATCH v7 10/13] migration: Export ram_release_page(), Juan Quintela, 2022/05/31
- [PATCH v7 12/13] multifd: Zero pages transmission, Juan Quintela, 2022/05/31
- [PATCH v7 11/13] multifd: Support for zero pages transmission, Juan Quintela, 2022/05/31
- [PATCH v7 13/13] migration: Use multifd before we check for the zero page, Juan Quintela, 2022/05/31