@@ -715,7 +715,69 @@ static int ram_save_page(QEMUFile *f, RAMBlock* block, ram_addr_t offset,
return pages;
}
-/**
+/*
+ * Queue the pages for transmission, e.g. a request from postcopy destination
+ * ms: MigrationStatus in which the queue is held
+ * rbname: The RAMBlock the request is for - may be NULL (to mean reuse last)
+ * start: Offset from the start of the RAMBlock
+ * len: Length (in bytes) to send
+ * Return: 0 on success
+ */
+int ram_save_queue_pages(MigrationState *ms, const char *rbname,
+ ram_addr_t start, ram_addr_t len)
+{
+ RAMBlock *ramblock;
+
+ rcu_read_lock();
+ if (!rbname) {
+ /* Reuse last RAMBlock */
+ ramblock = ms->last_req_rb;
+
+ if (!ramblock) {
+ /*
+ * Shouldn't happen, we can't reuse the last RAMBlock if
+ * it's the 1st request.
+ */
+ error_report("ram_save_queue_pages no previous block");
+ goto err;
+ }
+ } else {
+ ramblock = ram_find_block(rbname);
+
+ if (!ramblock) {
+ /* We shouldn't be asked for a non-existent RAMBlock */
+ error_report("ram_save_queue_pages no block '%s'", rbname);
+ goto err;
+ }
+ }
+ trace_ram_save_queue_pages(ramblock->idstr, start, len);
+ if (start+len > ramblock->used_length) {
+ error_report("%s request overrun start=%zx len=%zx blocklen=%zx",
+ __func__, start, len, ramblock->used_length);
+ goto err;
+ }
+
+ struct MigrationSrcPageRequest *new_entry =
+ g_malloc0(sizeof(struct MigrationSrcPageRequest));
+ new_entry->rb = ramblock;
+ new_entry->offset = start;
+ new_entry->len = len;
+ ms->last_req_rb = ramblock;
+
+ qemu_mutex_lock(&ms->src_page_req_mutex);
+ memory_region_ref(ramblock->mr);
+ QSIMPLEQ_INSERT_TAIL(&ms->src_page_requests, new_entry, next_req);
+ qemu_mutex_unlock(&ms->src_page_req_mutex);
+ rcu_read_unlock();
+
+ return 0;
+
+err:
+ rcu_read_unlock();
+ return -1;
+}
+
+/*
* ram_find_and_save_block: Finds a dirty page and sends it to f
*
* Called within an RCU critical section.
@@ -266,8 +266,6 @@ CPUArchState *cpu_copy(CPUArchState *env);
/* memory API */
-typedef struct RAMBlock RAMBlock;
-
struct RAMBlock {
struct rcu_head rcu;
struct MemoryRegion *mr;
@@ -88,6 +88,18 @@ MigrationIncomingState *migration_incoming_get_current(void);
MigrationIncomingState *migration_incoming_state_new(QEMUFile *f);
void migration_incoming_state_destroy(void);
+/*
+ * An outstanding page request, on the source, having been received
+ * and queued
+ */
+struct MigrationSrcPageRequest {
+ RAMBlock *rb;
+ hwaddr offset;
+ hwaddr len;
+
+ QSIMPLEQ_ENTRY(MigrationSrcPageRequest) next_req;
+};
+
struct MigrationState
{
int64_t bandwidth_limit;
@@ -130,6 +142,12 @@ struct MigrationState
* of the postcopy phase
*/
unsigned long *sentmap;
+
+ /* Queue of outstanding page requests from the destination */
+ QemuMutex src_page_req_mutex;
+ QSIMPLEQ_HEAD(src_page_requests, MigrationSrcPageRequest) src_page_requests;
+ /* The RAMBlock used in the last src_page_request */
+ RAMBlock *last_req_rb;
};
void process_incoming_migration(QEMUFile *f);
@@ -259,6 +277,9 @@ size_t ram_control_save_page(QEMUFile *f, ram_addr_t block_offset,
ram_addr_t offset, size_t size,
uint64_t *bytes_sent);
+int ram_save_queue_pages(MigrationState *ms, const char *rbname,
+ ram_addr_t start, ram_addr_t len);
+
PostcopyState postcopy_state_get(MigrationIncomingState *mis);
/* Set the state and return the old state */
@@ -72,6 +72,7 @@ typedef struct QEMUSGList QEMUSGList;
typedef struct QEMUSizedBuffer QEMUSizedBuffer;
typedef struct QEMUTimerListGroup QEMUTimerListGroup;
typedef struct QEMUTimer QEMUTimer;
+typedef struct RAMBlock RAMBlock;
typedef struct Range Range;
typedef struct SerialState SerialState;
typedef struct SHPCDevice SHPCDevice;
@@ -26,6 +26,8 @@
#include "qemu/thread.h"
#include "qmp-commands.h"
#include "trace.h"
+#include "exec/memory.h"
+#include "exec/address-spaces.h"
#define MAX_THROTTLE (32 << 20) /* Migration speed throttling */
@@ -496,6 +498,15 @@ static void migrate_fd_cleanup(void *opaque)
migrate_fd_cleanup_src_rp(s);
+ /* This queue generally should be empty - but in the case of a failed
+ * migration might have some droppings in.
+ */
+ struct MigrationSrcPageRequest *mspr, *next_mspr;
+ QSIMPLEQ_FOREACH_SAFE(mspr, &s->src_page_requests, next_req, next_mspr) {
+ QSIMPLEQ_REMOVE_HEAD(&s->src_page_requests, next_req);
+ g_free(mspr);
+ }
+
if (s->file) {
trace_migrate_fd_cleanup();
qemu_mutex_unlock_iothread();
@@ -614,6 +625,9 @@ MigrationState *migrate_init(const MigrationParams *params)
s->state = MIGRATION_STATUS_SETUP;
trace_migrate_set_state(MIGRATION_STATUS_SETUP);
+ qemu_mutex_init(&s->src_page_req_mutex);
+ QSIMPLEQ_INIT(&s->src_page_requests);
+
s->total_time = qemu_clock_get_ms(QEMU_CLOCK_REALTIME);
return s;
}
@@ -842,6 +856,23 @@ static void migrate_handle_rp_req_pages(MigrationState *ms, const char* rbname,
ram_addr_t start, ram_addr_t len)
{
trace_migrate_handle_rp_req_pages(rbname, start, len);
+
+ /* Round everything up to our host page size */
+ long our_host_ps = getpagesize();
+ if (start & (our_host_ps-1)) {
+ long roundings = start & (our_host_ps-1);
+ start -= roundings;
+ len += roundings;
+ }
+ if (len & (our_host_ps-1)) {
+ long roundings = len & (our_host_ps-1);
+ len -= roundings;
+ len += our_host_ps;
+ }
+
+ if (ram_save_queue_pages(ms, rbname, start, len)) {
+ source_return_path_bad(ms);
+ }
}
/*
@@ -1220,6 +1220,7 @@ migration_bitmap_sync_start(void) ""
migration_bitmap_sync_end(uint64_t dirty_pages) "dirty_pages %" PRIu64""
migration_throttle(void) ""
ram_postcopy_send_discard_bitmap(void) ""
+ram_save_queue_pages(const char *rbname, size_t start, size_t len) "%s: start: %zx len: %zx"
# hw/display/qxl.c
disable qxl_interface_set_mm_time(int qid, uint32_t mm_time) "%d %d"