From c70c97cd59fd22de0957ea1c0a655fb5ef270f1e Mon Sep 17 00:00:00 2001
From: Juan Quintela <quintela@redhat.com>
Date: Wed, 18 May 2022 02:52:24 -0300
Subject: [PATCH 16/34] multifd: Use normal pages array on the send side
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RH-Author: Leonardo Brás <leobras@redhat.com>
RH-MergeRequest: 185: MSG_ZEROCOPY + Multifd @ rhel8.6
RH-Commit: [16/34] 24f4ea3248f6ce883d57344600c8adbf51bd7d8c
RH-Bugzilla: 2117252
RH-Acked-by: quintela1 <quintela@redhat.com>
RH-Acked-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
RH-Acked-by: Peter Xu <peterx@redhat.com>
We are only sending normal pages through multifd channels.
Later on this series, we are going to also send zero pages.
We are going to detect if a page is zero or non zero in the multifd
channel thread, not on the main thread.
So we receive an array of pages page->offset[N]
And we will end with:
p->normal[N - zero_pages]
p->zero[zero_pages].
In this patch, we just copy all the pages in offset to normal.
for (i = 0; i < pages->num; i++) {
p->narmal[p->normal_num] = pages->offset[i];
p->normal_num++:
}
Later in the series this becomes:
for (i = 0; i < pages->num; i++) {
if (buffer_is_zero(page->offset[i])) {
p->zerol[p->zero_num] = pages->offset[i];
p->zero_num++:
} else {
p->narmal[p->normal_num] = pages->offset[i];
p->normal_num++:
}
}
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
---
Improving comment (dave)
Renaming num_normal_pages to total_normal_pages (peter)
(cherry picked from commit 815956f03902980c771da64b17f7f791c1cb57b0)
Signed-off-by: Leonardo Bras <leobras@redhat.com>
---
migration/multifd-zlib.c | 6 +++---
migration/multifd-zstd.c | 6 +++---
migration/multifd.c | 30 +++++++++++++++++++-----------
migration/multifd.h | 8 ++++++--
migration/trace-events | 4 ++--
5 files changed, 33 insertions(+), 21 deletions(-)
diff --git a/migration/multifd-zlib.c b/migration/multifd-zlib.c
index 8ed29b9633..8508f26adf 100644
--- a/migration/multifd-zlib.c
+++ b/migration/multifd-zlib.c
@@ -108,16 +108,16 @@ static int zlib_send_prepare(MultiFDSendParams *p, Error **errp)
int ret;
uint32_t i;
- for (i = 0; i < p->pages->num; i++) {
+ for (i = 0; i < p->normal_num; i++) {
uint32_t available = z->zbuff_len - out_size;
int flush = Z_NO_FLUSH;
- if (i == p->pages->num - 1) {
+ if (i == p->normal_num - 1) {
flush = Z_SYNC_FLUSH;
}
zs->avail_in = page_size;
- zs->next_in = p->pages->block->host + p->pages->offset[i];
+ zs->next_in = p->pages->block->host + p->normal[i];
zs->avail_out = available;
zs->next_out = z->zbuff + out_size;
diff --git a/migration/multifd-zstd.c b/migration/multifd-zstd.c
index 25e1f517b5..693af3a140 100644
--- a/migration/multifd-zstd.c
+++ b/migration/multifd-zstd.c
@@ -123,13 +123,13 @@ static int zstd_send_prepare(MultiFDSendParams *p, Error **errp)
z->out.size = z->zbuff_len;
z->out.pos = 0;
- for (i = 0; i < p->pages->num; i++) {
+ for (i = 0; i < p->normal_num; i++) {
ZSTD_EndDirective flush = ZSTD_e_continue;
- if (i == p->pages->num - 1) {
+ if (i == p->normal_num - 1) {
flush = ZSTD_e_flush;
}
- z->in.src = p->pages->block->host + p->pages->offset[i];
+ z->in.src = p->pages->block->host + p->normal[i];
z->in.size = page_size;
z->in.pos = 0;
diff --git a/migration/multifd.c b/migration/multifd.c
index d0f86542b1..3725226400 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->pages->num; i++) {
- p->iov[p->iovs_num].iov_base = pages->block->host + pages->offset[i];
+ for (int i = 0; i < p->normal_num; i++) {
+ p->iov[p->iovs_num].iov_base = pages->block->host + p->normal[i];
p->iov[p->iovs_num].iov_len = page_size;
p->iovs_num++;
}
- p->next_packet_size = p->pages->num * page_size;
+ p->next_packet_size = p->normal_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->pages_used = cpu_to_be32(p->pages->num);
+ packet->pages_used = cpu_to_be32(p->normal_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->pages->num; i++) {
+ for (i = 0; i < p->normal_num; i++) {
/* there are architectures where ram_addr_t is 32 bit */
- uint64_t temp = p->pages->offset[i];
+ uint64_t temp = p->normal[i];
packet->offset[i] = cpu_to_be64(temp);
}
@@ -556,6 +556,8 @@ void multifd_save_cleanup(void)
p->packet = NULL;
g_free(p->iov);
p->iov = NULL;
+ g_free(p->normal);
+ p->normal = NULL;
multifd_send_state->ops->send_cleanup(p, &local_err);
if (local_err) {
migrate_set_error(migrate_get_current(), local_err);
@@ -640,12 +642,17 @@ static void *multifd_send_thread(void *opaque)
qemu_mutex_lock(&p->mutex);
if (p->pending_job) {
- uint32_t used = p->pages->num;
uint64_t packet_num = p->packet_num;
uint32_t flags = p->flags;
p->iovs_num = 1;
+ p->normal_num = 0;
+
+ for (int i = 0; i < p->pages->num; i++) {
+ p->normal[p->normal_num] = p->pages->offset[i];
+ p->normal_num++;
+ }
- if (used) {
+ if (p->normal_num) {
ret = multifd_send_state->ops->send_prepare(p, &local_err);
if (ret != 0) {
qemu_mutex_unlock(&p->mutex);
@@ -655,12 +662,12 @@ static void *multifd_send_thread(void *opaque)
multifd_send_fill_packet(p);
p->flags = 0;
p->num_packets++;
- p->num_pages += used;
+ 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, used, flags,
+ trace_multifd_send(p->id, packet_num, p->normal_num, flags,
p->next_packet_size);
p->iov[0].iov_len = p->packet_len;
@@ -710,7 +717,7 @@ out:
qemu_mutex_unlock(&p->mutex);
rcu_unregister_thread();
- trace_multifd_send_thread_end(p->id, p->num_packets, p->num_pages);
+ trace_multifd_send_thread_end(p->id, p->num_packets, p->total_normal_pages);
return NULL;
}
@@ -910,6 +917,7 @@ int multifd_save_setup(Error **errp)
p->tls_hostname = g_strdup(s->hostname);
/* We need one extra place for the packet header */
p->iov = g_new0(struct iovec, page_count + 1);
+ p->normal = g_new0(ram_addr_t, page_count);
socket_send_channel_create(multifd_new_send_channel_async, p);
}
diff --git a/migration/multifd.h b/migration/multifd.h
index 7496f951a7..7823199dbe 100644
--- a/migration/multifd.h
+++ b/migration/multifd.h
@@ -104,14 +104,18 @@ typedef struct {
/* thread local variables */
/* packets sent through this channel */
uint64_t num_packets;
- /* pages sent through this channel */
- uint64_t num_pages;
+ /* non zero pages sent through this channel */
+ uint64_t total_normal_pages;
/* syncs main thread and channels */
QemuSemaphore sem_sync;
/* buffers to send */
struct iovec *iov;
/* number of iovs used */
uint32_t iovs_num;
+ /* Pages that are not zero */
+ ram_addr_t *normal;
+ /* num of non zero pages */
+ uint32_t normal_num;
/* used for compression methods */
void *data;
} MultiFDSendParams;
diff --git a/migration/trace-events b/migration/trace-events
index 5172cb3b3d..171a83a55d 100644
--- a/migration/trace-events
+++ b/migration/trace-events
@@ -124,13 +124,13 @@ multifd_recv_sync_main_wait(uint8_t id) "channel %u"
multifd_recv_terminate_threads(bool error) "error %d"
multifd_recv_thread_end(uint8_t id, uint64_t packets, uint64_t pages) "channel %u packets %" PRIu64 " pages %" PRIu64
multifd_recv_thread_start(uint8_t id) "%u"
-multifd_send(uint8_t id, uint64_t packet_num, uint32_t used, uint32_t flags, uint32_t next_packet_size) "channel %u packet_num %" PRIu64 " pages %u flags 0x%x next packet size %u"
+multifd_send(uint8_t id, uint64_t packet_num, uint32_t normal, uint32_t flags, uint32_t next_packet_size) "channel %u packet_num %" PRIu64 " normal pages %u flags 0x%x next packet size %u"
multifd_send_error(uint8_t id) "channel %u"
multifd_send_sync_main(long packet_num) "packet num %ld"
multifd_send_sync_main_signal(uint8_t id) "channel %u"
multifd_send_sync_main_wait(uint8_t id) "channel %u"
multifd_send_terminate_threads(bool error) "error %d"
-multifd_send_thread_end(uint8_t id, uint64_t packets, uint64_t pages) "channel %u packets %" PRIu64 " pages %" PRIu64
+multifd_send_thread_end(uint8_t id, uint64_t packets, uint64_t normal_pages) "channel %u packets %" PRIu64 " normal pages %" PRIu64
multifd_send_thread_start(uint8_t id) "%u"
multifd_tls_outgoing_handshake_start(void *ioc, void *tioc, const char *hostname) "ioc=%p tioc=%p hostname=%s"
multifd_tls_outgoing_handshake_error(void *ioc, const char *err) "ioc=%p err=%s"
--
2.35.3