[Qemu-devel] [PULL 40/57] Page request: Add MIG_RP_MSG_REQ_PAGES reverse command
From: "Dr. David Alan Gilbert"
Add MIG_RP_MSG_REQ_PAGES command on Return path for the postcopy
destination to request a page from the source.
Two versions exist:
MIG_RP_MSG_REQ_PAGES_ID that includes a RAMBlock name and start/len
MIG_RP_MSG_REQ_PAGES that just has start/len for use with the same
RAMBlock as a previous MIG_RP_MSG_REQ_PAGES_ID
Signed-off-by: Dr. David Alan Gilbert
Reviewed-by: Juan Quintela
Reviewed-by: Amit Shah
Signed-off-by: Juan Quintela
---
include/migration/migration.h | 5
migration/migration.c | 70 +++
trace-events | 1 +
3 files changed, 76 insertions(+)
diff --git a/include/migration/migration.h b/include/migration/migration.h
index ff13ff2..1046d4e 100644
--- a/include/migration/migration.h
+++ b/include/migration/migration.h
@@ -49,6 +49,9 @@ enum mig_rp_message_type {
MIG_RP_MSG_SHUT, /* sibling will not send any more RP messages */
MIG_RP_MSG_PONG, /* Response to a PING; data (seq: be32 ) */
+MIG_RP_MSG_REQ_PAGES_ID, /* data (start: be64, len: be32, id: string) */
+MIG_RP_MSG_REQ_PAGES,/* data (start: be64, len: be32) */
+
MIG_RP_MSG_MAX
};
@@ -256,6 +259,8 @@ void migrate_send_rp_shut(MigrationIncomingState *mis,
uint32_t value);
void migrate_send_rp_pong(MigrationIncomingState *mis,
uint32_t value);
+void migrate_send_rp_req_pages(MigrationIncomingState *mis, const char* rbname,
+ ram_addr_t start, size_t len);
void ram_control_before_iterate(QEMUFile *f, uint64_t flags);
void ram_control_after_iterate(QEMUFile *f, uint64_t flags);
diff --git a/migration/migration.c b/migration/migration.c
index b860777..ba0da4f 100644
--- a/migration/migration.c
+++ b/migration/migration.c
@@ -259,6 +259,35 @@ static void deferred_incoming_migration(Error **errp)
deferred_incoming = true;
}
+/* Request a range of pages from the source VM at the given
+ * start address.
+ * rbname: Name of the RAMBlock to request the page in, if NULL it's the same
+ * as the last request (a name must have been given previously)
+ * Start: Address offset within the RB
+ * Len: Length in bytes required - must be a multiple of pagesize
+ */
+void migrate_send_rp_req_pages(MigrationIncomingState *mis, const char *rbname,
+ ram_addr_t start, size_t len)
+{
+uint8_t bufc[12 + 1 + 255]; /* start (8), len (4), rbname upto 256 */
+size_t msglen = 12; /* start + len */
+
+*(uint64_t *)bufc = cpu_to_be64((uint64_t)start);
+*(uint32_t *)(bufc + 8) = cpu_to_be32((uint32_t)len);
+
+if (rbname) {
+int rbname_len = strlen(rbname);
+assert(rbname_len < 256);
+
+bufc[msglen++] = rbname_len;
+memcpy(bufc + msglen, rbname, rbname_len);
+msglen += rbname_len;
+migrate_send_rp_message(mis, MIG_RP_MSG_REQ_PAGES_ID, msglen, bufc);
+} else {
+migrate_send_rp_message(mis, MIG_RP_MSG_REQ_PAGES, msglen, bufc);
+}
+}
+
void qemu_start_incoming_migration(const char *uri, Error **errp)
{
const char *p;
@@ -1151,10 +1180,23 @@ static struct rp_cmd_args {
[MIG_RP_MSG_INVALID]= { .len = -1, .name = "INVALID" },
[MIG_RP_MSG_SHUT] = { .len = 4, .name = "SHUT" },
[MIG_RP_MSG_PONG] = { .len = 4, .name = "PONG" },
+[MIG_RP_MSG_REQ_PAGES] = { .len = 12, .name = "REQ_PAGES" },
+[MIG_RP_MSG_REQ_PAGES_ID] = { .len = -1, .name = "REQ_PAGES_ID" },
[MIG_RP_MSG_MAX]= { .len = -1, .name = "MAX" },
};
/*
+ * Process a request for pages received on the return path,
+ * We're allowed to send more than requested (e.g. to round to our page size)
+ * and we don't need to send pages that have already been sent.
+ */
+static void migrate_handle_rp_req_pages(MigrationState *ms, const char* rbname,
+ ram_addr_t start, size_t len)
+{
+trace_migrate_handle_rp_req_pages(rbname, start, len);
+}
+
+/*
* Handles messages sent on the return path towards the source VM
*
*/
@@ -1166,6 +1208,8 @@ static void *source_return_path_thread(void *opaque)
const int max_len = 512;
uint8_t buf[max_len];
uint32_t tmp32, sibling_error;
+ram_addr_t start = 0; /* =0 to silence warning */
+size_t len = 0, expected_len;
int res;
trace_source_return_path_thread_entry();
@@ -1225,6 +1269,32 @@ static void *source_return_path_thread(void *opaque)
trace_source_return_path_thread_pong(tmp32);
break;
+case MIG_RP_MSG_REQ_PAGES:
+start = be64_to_cpup((uint64_t *)buf);
+len = be32_to_cpup((uint32_t *)(buf + 8));
+migrate_handle_rp_req_pages(ms, NULL, start, len);
+break;
+
+case MIG_RP_MSG_REQ_PAGES_ID:
+expected_len = 12 + 1; /* header + termination */
[Qemu-devel] [PULL 40/57] Page request: Add MIG_RP_MSG_REQ_PAGES reverse command
From: "Dr. David Alan Gilbert"
Add MIG_RP_MSG_REQ_PAGES command on Return path for the postcopy
destination to request a page from the source.
Two versions exist:
MIG_RP_MSG_REQ_PAGES_ID that includes a RAMBlock name and start/len
MIG_RP_MSG_REQ_PAGES that just has start/len for use with the same
RAMBlock as a previous MIG_RP_MSG_REQ_PAGES_ID
Signed-off-by: Dr. David Alan Gilbert
Reviewed-by: Juan Quintela
Reviewed-by: Amit Shah
Signed-off-by: Juan Quintela
---
include/migration/migration.h | 5
migration/migration.c | 70 +++
trace-events | 1 +
3 files changed, 76 insertions(+)
diff --git a/include/migration/migration.h b/include/migration/migration.h
index ff13ff2..1046d4e 100644
--- a/include/migration/migration.h
+++ b/include/migration/migration.h
@@ -49,6 +49,9 @@ enum mig_rp_message_type {
MIG_RP_MSG_SHUT, /* sibling will not send any more RP messages */
MIG_RP_MSG_PONG, /* Response to a PING; data (seq: be32 ) */
+MIG_RP_MSG_REQ_PAGES_ID, /* data (start: be64, len: be32, id: string) */
+MIG_RP_MSG_REQ_PAGES,/* data (start: be64, len: be32) */
+
MIG_RP_MSG_MAX
};
@@ -256,6 +259,8 @@ void migrate_send_rp_shut(MigrationIncomingState *mis,
uint32_t value);
void migrate_send_rp_pong(MigrationIncomingState *mis,
uint32_t value);
+void migrate_send_rp_req_pages(MigrationIncomingState *mis, const char* rbname,
+ ram_addr_t start, size_t len);
void ram_control_before_iterate(QEMUFile *f, uint64_t flags);
void ram_control_after_iterate(QEMUFile *f, uint64_t flags);
diff --git a/migration/migration.c b/migration/migration.c
index 3cdb4f7..6ccdeb8 100644
--- a/migration/migration.c
+++ b/migration/migration.c
@@ -259,6 +259,35 @@ static void deferred_incoming_migration(Error **errp)
deferred_incoming = true;
}
+/* Request a range of pages from the source VM at the given
+ * start address.
+ * rbname: Name of the RAMBlock to request the page in, if NULL it's the same
+ * as the last request (a name must have been given previously)
+ * Start: Address offset within the RB
+ * Len: Length in bytes required - must be a multiple of pagesize
+ */
+void migrate_send_rp_req_pages(MigrationIncomingState *mis, const char *rbname,
+ ram_addr_t start, size_t len)
+{
+uint8_t bufc[12 + 1 + 255]; /* start (8), len (4), rbname upto 256 */
+size_t msglen = 12; /* start + len */
+
+*(uint64_t *)bufc = cpu_to_be64((uint64_t)start);
+*(uint32_t *)(bufc + 8) = cpu_to_be32((uint32_t)len);
+
+if (rbname) {
+int rbname_len = strlen(rbname);
+assert(rbname_len < 256);
+
+bufc[msglen++] = rbname_len;
+memcpy(bufc + msglen, rbname, rbname_len);
+msglen += rbname_len;
+migrate_send_rp_message(mis, MIG_RP_MSG_REQ_PAGES_ID, msglen, bufc);
+} else {
+migrate_send_rp_message(mis, MIG_RP_MSG_REQ_PAGES, msglen, bufc);
+}
+}
+
void qemu_start_incoming_migration(const char *uri, Error **errp)
{
const char *p;
@@ -1151,10 +1180,23 @@ static struct rp_cmd_args {
[MIG_RP_MSG_INVALID]= { .len = -1, .name = "INVALID" },
[MIG_RP_MSG_SHUT] = { .len = 4, .name = "SHUT" },
[MIG_RP_MSG_PONG] = { .len = 4, .name = "PONG" },
+[MIG_RP_MSG_REQ_PAGES] = { .len = 12, .name = "REQ_PAGES" },
+[MIG_RP_MSG_REQ_PAGES_ID] = { .len = -1, .name = "REQ_PAGES_ID" },
[MIG_RP_MSG_MAX]= { .len = -1, .name = "MAX" },
};
/*
+ * Process a request for pages received on the return path,
+ * We're allowed to send more than requested (e.g. to round to our page size)
+ * and we don't need to send pages that have already been sent.
+ */
+static void migrate_handle_rp_req_pages(MigrationState *ms, const char* rbname,
+ ram_addr_t start, size_t len)
+{
+trace_migrate_handle_rp_req_pages(rbname, start, len);
+}
+
+/*
* Handles messages sent on the return path towards the source VM
*
*/
@@ -1166,6 +1208,8 @@ static void *source_return_path_thread(void *opaque)
const int max_len = 512;
uint8_t buf[max_len];
uint32_t tmp32, sibling_error;
+ram_addr_t start = 0; /* =0 to silence warning */
+size_t len = 0, expected_len;
int res;
trace_source_return_path_thread_entry();
@@ -1225,6 +1269,32 @@ static void *source_return_path_thread(void *opaque)
trace_source_return_path_thread_pong(tmp32);
break;
+case MIG_RP_MSG_REQ_PAGES:
+start = be64_to_cpup((uint64_t *)buf);
+len = be32_to_cpup((uint32_t *)(buf + 8));
+migrate_handle_rp_req_pages(ms, NULL, start, len);
+break;
+
+case MIG_RP_MSG_REQ_PAGES_ID:
+expected_len = 12 + 1; /* header + termination */
