From: "Dr. David Alan Gilbert" <dgilb...@redhat.com>
On receiving MIG_RPCOMM_REQPAGES look up the address and
queue the page.
Signed-off-by: Dr. David Alan Gilbert <dgilb...@redhat.com>
---
arch_init.c | 52 +++++++++++++++++++++++++++++++++++++++++++
include/migration/migration.h | 21 +++++++++++++++++
include/qemu/typedefs.h | 3 ++-
migration.c | 34 +++++++++++++++++++++++++++-
4 files changed, 108 insertions(+), 2 deletions(-)
diff --git a/arch_init.c b/arch_init.c
index 4a03171..72f9e17 100644
--- a/arch_init.c
+++ b/arch_init.c
@@ -660,6 +660,58 @@ static int ram_save_page(QEMUFile *f, RAMBlock* block,
ram_addr_t offset,
}
/*
+ * 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;
+
+ if (!rbname) {
+ /* Reuse last RAMBlock */
+ ramblock = ms->last_req_rb;
+
+ if (!ramblock) {
+ error_report("ram_save_queue_pages no previous block");
+ return -1;
+ }
+ } else {
+ ramblock = ram_find_block(rbname);
+
+ if (!ramblock) {
+ error_report("ram_save_queue_pages no block '%s'", rbname);
+ return -1;
+ }
+ }
+ DPRINTF("ram_save_queue_pages: Block %s start %zx len %zx",
+ ramblock->idstr, start, len);
+
+ if (start+len > ramblock->length) {
+ error_report("%s request overrun start=%zx len=%zx blocklen=%zx",
+ __func__, start, len, ramblock->length);
+ return -1;
+ }
+
+ 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);
+ QSIMPLEQ_INSERT_TAIL(&ms->src_page_requests, new_entry, next_req);
+ qemu_mutex_unlock(&ms->src_page_req_mutex);
+
+ return 0;
+}
+
+/*
* ram_find_and_save_block: Finds a page to send and sends it to f
*
* Returns: The number of bytes written.
diff --git a/include/migration/migration.h b/include/migration/migration.h
index 5e0d30d..5bc01d5 100644
--- a/include/migration/migration.h
+++ b/include/migration/migration.h
@@ -102,6 +102,18 @@ MigrationIncomingState
*migration_incoming_get_current(void);
MigrationIncomingState *migration_incoming_state_init(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;
@@ -138,6 +150,12 @@ 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);
@@ -273,4 +291,7 @@ size_t ram_control_save_page(QEMUFile *f, ram_addr_t
block_offset,
ram_addr_t offset, size_t size,
int *bytes_sent);
+int ram_save_queue_pages(MigrationState *ms, const char *rbname,
+ ram_addr_t start, ram_addr_t len);
+
#endif
diff --git a/include/qemu/typedefs.h b/include/qemu/typedefs.h
index 79f57c0..24c2207 100644
--- a/include/qemu/typedefs.h
+++ b/include/qemu/typedefs.h
@@ -8,6 +8,7 @@ typedef struct QEMUTimerListGroup QEMUTimerListGroup;
typedef struct QEMUFile QEMUFile;
typedef struct QEMUBH QEMUBH;
+typedef struct AdapterInfo AdapterInfo;
typedef struct AioContext AioContext;
typedef struct Visitor Visitor;
@@ -80,6 +81,6 @@ typedef struct FWCfgState FWCfgState;
typedef struct PcGuestInfo PcGuestInfo;
typedef struct PostcopyPMI PostcopyPMI;
typedef struct Range Range;
-typedef struct AdapterInfo AdapterInfo;
+typedef struct RAMBlock RAMBlock;
#endif /* QEMU_TYPEDEFS_H */
diff --git a/migration.c b/migration.c
index cfdaa52..63d7699 100644
--- a/migration.c
+++ b/migration.c
@@ -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 DEBUG_MIGRATION
@@ -504,6 +506,15 @@ 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();
@@ -610,6 +621,9 @@ MigrationState *migrate_init(const MigrationParams *params)
s->state = MIG_STATE_SETUP;
trace_migrate_set_state(MIG_STATE_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;
}
@@ -823,7 +837,25 @@ static void source_return_path_bad(MigrationState *s)
static void migrate_handle_rp_reqpages(MigrationState *ms, const char* rbname,
ram_addr_t start, ram_addr_t len)
{
- DPRINTF("migrate_handle_rp_reqpages: at %zx for len %zx", start, len);
+ DPRINTF("migrate_handle_rp_reqpages: in %s start %zx len %zx",
+ rbname, start, len);
+
+ /* Round everything up to our host page size */
+ long our_host_ps = sysconf(_SC_PAGESIZE);
+ 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);
+ }
}
/*
--
1.9.3
