The function still don't use multifd, but we have simplified
ram_save_page, xbzrle and RDMA stuff is gone. We have added a new
counter.
Signed-off-by: Juan Quintela <quint...@redhat.com>
--
Add last_page parameter
Add commets for done and address
Remove multifd field, it is the same than normal pages
Merge next patch, now we send multiple pages at a time
Remove counter for multifd pages, it is identical to normal pages
Use iovec's instead of creating the equivalent.
Clear memory used by pages (dave)
Use g_new0(danp)
define MULTIFD_CONTINUE
now pages member is a pointer
Fix off-by-one in number of pages in one packet
Remove RAM_SAVE_FLAG_MULTIFD_PAGE
---
migration/ram.c | 144 ++++++++++++++++++++++++++++++++++++++++++++++++-
migration/trace-events | 3 +-
2 files changed, 144 insertions(+), 3 deletions(-)
diff --git a/migration/ram.c b/migration/ram.c
index 4efac0c20c..df9646ed2e 100644
--- a/migration/ram.c
+++ b/migration/ram.c
@@ -54,6 +54,7 @@
#include "migration/block.h"
#include "sysemu/sysemu.h"
#include "qemu/uuid.h"
+#include "qemu/iov.h"
/***********************************************************/
/* ram save/restore */
@@ -397,7 +398,19 @@ static void compress_threads_save_setup(void)
/* Multiple fd's */
+typedef struct {
+ /* number of used pages */
+ uint32_t used;
+ /* number of allocated pages */
+ uint32_t allocated;
+ /* global number of generated multifd packets */
+ uint32_t seq;
+ struct iovec *iov;
+ RAMBlock *block;
+} multifd_pages_t;
+
struct MultiFDSendParams {
+ /* not changed */
uint8_t id;
char *name;
QemuThread thread;
@@ -405,8 +418,15 @@ struct MultiFDSendParams {
QemuSemaphore sem;
QemuMutex mutex;
bool running;
+ /* protected by param mutex */
bool quit;
bool sync;
+ multifd_pages_t *pages;
+ /* how many patches has sent this channel */
+ uint32_t packets_sent;
+ /* protected by multifd mutex */
+ /* has the thread finish the last submitted job */
+ bool done;
};
typedef struct MultiFDSendParams MultiFDSendParams;
@@ -416,8 +436,31 @@ struct {
int count;
/* syncs main thread and channels */
QemuSemaphore sem_main;
+ QemuMutex mutex;
+ QemuSemaphore sem;
+ multifd_pages_t *pages;
} *multifd_send_state;
+static void multifd_pages_init(multifd_pages_t **ppages, size_t size)
+{
+ multifd_pages_t *pages = g_new0(multifd_pages_t, 1);
+
+ pages->allocated = size;
+ pages->iov = g_new0(struct iovec, size);
+ *ppages = pages;
+}
+
+static void multifd_pages_clear(multifd_pages_t *pages)
+{
+ pages->used = 0;
+ pages->allocated = 0;
+ pages->seq = 0;
+ pages->block = NULL;
+ g_free(pages->iov);
+ pages->iov = NULL;
+ g_free(pages);
+}
+
static void terminate_multifd_send_threads(Error *errp)
{
int i;
@@ -464,10 +507,14 @@ int multifd_save_cleanup(Error **errp)
qemu_sem_destroy(&p->sem);
g_free(p->name);
p->name = NULL;
+ multifd_pages_clear(p->pages);
+ p->pages = NULL;
}
qemu_sem_destroy(&multifd_send_state->sem_main);
g_free(multifd_send_state->params);
multifd_send_state->params = NULL;
+ multifd_pages_clear(multifd_send_state->pages);
+ multifd_send_state->pages = NULL;
g_free(multifd_send_state);
multifd_send_state = NULL;
return ret;
@@ -516,6 +563,7 @@ static void *multifd_send_thread(void *opaque)
terminate_multifd_send_threads(local_err);
return NULL;
}
+ qemu_sem_post(&multifd_send_state->sem);
while (true) {
qemu_sem_wait(&p->sem);
@@ -530,9 +578,23 @@ static void *multifd_send_thread(void *opaque)
qemu_mutex_unlock(&p->mutex);
break;
}
+ if (p->pages->used) {
+ p->pages->used = 0;
+ qemu_mutex_unlock(&p->mutex);
+
+ trace_multifd_send(p->id, p->pages->seq, p->pages->used);
+ /* ToDo: send page here */
+
+ qemu_mutex_lock(&multifd_send_state->mutex);
+ p->done = true;
+ p->packets_sent++;
+ qemu_mutex_unlock(&multifd_send_state->mutex);
+ qemu_sem_post(&multifd_send_state->sem);
+ continue;
+ }
qemu_mutex_unlock(&p->mutex);
}
- trace_multifd_send_thread_end(p->id);
+ trace_multifd_send_thread_end(p->id, p->packets_sent);
return NULL;
}
@@ -571,7 +633,10 @@ int multifd_save_setup(void)
multifd_send_state->params = g_new0(MultiFDSendParams, thread_count);
atomic_set(&multifd_send_state->count, 0);
qemu_sem_init(&multifd_send_state->sem_main, 0);
-
+ qemu_mutex_init(&multifd_send_state->mutex);
+ qemu_sem_init(&multifd_send_state->sem, 0);
+ multifd_pages_init(&multifd_send_state->pages,
+ migrate_multifd_page_count());
for (i = 0; i < thread_count; i++) {
MultiFDSendParams *p = &multifd_send_state->params[i];
@@ -579,6 +644,8 @@ int multifd_save_setup(void)
qemu_sem_init(&p->sem, 0);
p->quit = false;
p->id = i;
+ p->done = true;
+ multifd_pages_init(&p->pages, migrate_multifd_page_count());
p->name = g_strdup_printf("multifdsend_%d", i);
socket_send_channel_create(multifd_new_send_channel_async, p);
}
@@ -586,6 +653,50 @@ int multifd_save_setup(void)
return 0;
}
+static void multifd_send_page(RAMBlock *block, ram_addr_t offset,
+ bool last_page)
+{
+ int i;
+ static int next_channel = 0;
+ MultiFDSendParams *p = NULL; /* make happy gcc */
+ multifd_pages_t *pages = multifd_send_state->pages;
+
+ if (!pages->block) {
+ pages->block = block;
+ }
+
+ pages->iov[pages->used].iov_base = block->host + offset;
+ pages->iov[pages->used].iov_len = TARGET_PAGE_SIZE;
+ pages->used++;
+
+ if (!last_page) {
+ if (pages->used < pages->allocated) {
+ return;
+ }
+ }
+
+ qemu_sem_wait(&multifd_send_state->sem);
+ qemu_mutex_lock(&multifd_send_state->mutex);
+ for (i = next_channel;; i = (i + 1) % migrate_multifd_channels() ) {
+ p = &multifd_send_state->params[i];
+
+ if (p->done) {
+ p->done = false;
+ next_channel = (i + 1) % migrate_multifd_channels();
+ break;
+ }
+ }
+ qemu_mutex_unlock(&multifd_send_state->mutex);
+ qemu_mutex_lock(&p->mutex);
+ p->pages->used = 0;
+ p->pages->seq = pages->seq + 1;
+ p->pages->block = NULL;
+ multifd_send_state->pages = p->pages;
+ p->pages = pages;
+ qemu_mutex_unlock(&p->mutex);
+ qemu_sem_post(&p->sem);
+}
+
struct MultiFDRecvParams {
uint8_t id;
char *name;
@@ -1220,6 +1331,31 @@ static int ram_save_page(RAMState *rs, PageSearchStatus
*pss, bool last_stage)
return pages;
}
+static int ram_multifd_page(RAMState *rs, PageSearchStatus *pss,
+ bool last_stage)
+{
+ int pages;
+ uint8_t *p;
+ RAMBlock *block = pss->block;
+ ram_addr_t offset = pss->page << TARGET_PAGE_BITS;
+
+ p = block->host + offset;
+
+ pages = save_zero_page(rs, block, offset);
+ if (pages == -1) {
+ ram_counters.transferred +=
+ save_page_header(rs, rs->f, block,
+ offset | RAM_SAVE_FLAG_PAGE);
+ multifd_send_page(block, offset, rs->migration_dirty_pages == 1);
+ qemu_put_buffer(rs->f, p, TARGET_PAGE_SIZE);
+ ram_counters.transferred += TARGET_PAGE_SIZE;
+ pages = 1;
+ ram_counters.normal++;
+ }
+
+ return pages;
+}
+
static int do_compress_ram_page(QEMUFile *f, RAMBlock *block,
ram_addr_t offset)
{
@@ -1648,6 +1784,8 @@ static int ram_save_target_page(RAMState *rs,
PageSearchStatus *pss,
if (migrate_use_compression() &&
(rs->ram_bulk_stage || !migrate_use_xbzrle())) {
res = ram_save_compressed_page(rs, pss, last_stage);
+ } else if (migrate_use_multifd()) {
+ res = ram_multifd_page(rs, pss, last_stage);
} else {
res = ram_save_page(rs, pss, last_stage);
}
@@ -3047,6 +3185,7 @@ static int ram_load(QEMUFile *f, void *opaque, int
version_id)
if (!migrate_use_compression()) {
invalid_flags |= RAM_SAVE_FLAG_COMPRESS_PAGE;
}
+
/* This RCU critical section can be very long running.
* When RCU reclaims in the code start to become numerous,
* it will be necessary to reduce the granularity of this
@@ -3166,6 +3305,7 @@ static int ram_load(QEMUFile *f, void *opaque, int
version_id)
break;
}
break;
+
case RAM_SAVE_FLAG_EOS:
/* normal exit */
multifd_recv_sync_main();
diff --git a/migration/trace-events b/migration/trace-events
index db88fa699f..f6ab2c7bcb 100644
--- a/migration/trace-events
+++ b/migration/trace-events
@@ -80,9 +80,10 @@ ram_save_queue_pages(const char *rbname, size_t start,
size_t len) "%s: start: 0
multifd_send_sync_main(void) ""
multifd_recv_sync_main(void) ""
multifd_send_thread_start(int id) "%d"
-multifd_send_thread_end(int id) "%d"
+multifd_send_thread_end(char id, uint32_t packets) "channel %d packets %d"
multifd_recv_thread_start(int id) "%d"
multifd_recv_thread_end(int id) "%d"
+multifd_send(char id, int seq, int num) "channel %d sequence %d num pages %d"
# migration/migration.c
await_return_path_close_on_source_close(void) ""
--
2.14.3
