migration: Rework migrate_send_rp_req_pages() function

We duplicated the logic of maintaining the last_rb variable at both callers of
this function.  Pass *rb pointer into the function so that we can avoid
duplicating the logic.  Also, when we have the rb pointer, it's also easier to
remove the original 2nd & 4th parameters, because both of them (name of the
ramblock when needed, or the page size) can be fetched from the ramblock
pointer too.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20200908203022.341615-3-peterx@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
This commit is contained in:
Peter Xu 2020-09-08 16:30:18 -04:00 committed by Dr. David Alan Gilbert
parent c02039a6f3
commit 2e2bce167e
3 changed files with 22 additions and 32 deletions

View File

@ -314,25 +314,35 @@ error:
return ret;
}
/* 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)
/* Request one page from the source VM at the given start address.
* rb: the RAMBlock to request the page in
* Start: Address offset within the RB
* Len: Length in bytes required - must be a multiple of pagesize
*/
int migrate_send_rp_req_pages(MigrationIncomingState *mis, const char *rbname,
ram_addr_t start, size_t len)
int migrate_send_rp_req_pages(MigrationIncomingState *mis, RAMBlock *rb,
ram_addr_t start)
{
uint8_t bufc[12 + 1 + 255]; /* start (8), len (4), rbname up to 256 */
size_t msglen = 12; /* start + len */
size_t len = qemu_ram_pagesize(rb);
enum mig_rp_message_type msg_type;
const char *rbname;
int rbname_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);
/*
* We maintain the last ramblock that we requested for page. Note that we
* don't need locking because this function will only be called within the
* postcopy ram fault thread.
*/
if (rb != mis->last_rb) {
mis->last_rb = rb;
rbname = qemu_ram_get_idstr(rb);
rbname_len = strlen(rbname);
assert(rbname_len < 256);
bufc[msglen++] = rbname_len;

View File

@ -326,8 +326,8 @@ void migrate_send_rp_shut(MigrationIncomingState *mis,
uint32_t value);
void migrate_send_rp_pong(MigrationIncomingState *mis,
uint32_t value);
int migrate_send_rp_req_pages(MigrationIncomingState *mis, const char* rbname,
ram_addr_t start, size_t len);
int migrate_send_rp_req_pages(MigrationIncomingState *mis, RAMBlock *rb,
ram_addr_t start);
void migrate_send_rp_recv_bitmap(MigrationIncomingState *mis,
char *block_name);
void migrate_send_rp_resume_ack(MigrationIncomingState *mis, uint32_t value);

View File

@ -684,14 +684,7 @@ int postcopy_request_shared_page(struct PostCopyFD *pcfd, RAMBlock *rb,
qemu_ram_get_idstr(rb), rb_offset);
return postcopy_wake_shared(pcfd, client_addr, rb);
}
if (rb != mis->last_rb) {
mis->last_rb = rb;
migrate_send_rp_req_pages(mis, qemu_ram_get_idstr(rb),
aligned_rbo, pagesize);
} else {
/* Save some space */
migrate_send_rp_req_pages(mis, NULL, aligned_rbo, pagesize);
}
migrate_send_rp_req_pages(mis, rb, aligned_rbo);
return 0;
}
@ -986,20 +979,7 @@ retry:
* Send the request to the source - we want to request one
* of our host page sizes (which is >= TPS)
*/
if (rb != mis->last_rb) {
mis->last_rb = rb;
ret = migrate_send_rp_req_pages(mis,
qemu_ram_get_idstr(rb),
rb_offset,
qemu_ram_pagesize(rb));
} else {
/* Save some space */
ret = migrate_send_rp_req_pages(mis,
NULL,
rb_offset,
qemu_ram_pagesize(rb));
}
ret = migrate_send_rp_req_pages(mis, rb, rb_offset);
if (ret) {
/* May be network failure, try to wait for recovery */
if (ret == -EIO && postcopy_pause_fault_thread(mis)) {