ram compress: Assert that the file buffer matches the result

Before this series, "nothing to send" was handled by the file buffer
being empty. Now it is tracked via param->result.

Assert that the file buffer state matches the result.

Signed-off-by: Lukas Straub <lukasstraub2@web.de>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
This commit is contained in:
Lukas Straub 2023-04-20 11:48:31 +02:00 committed by Juan Quintela
parent b1f17720c1
commit 4024cc8506
4 changed files with 19 additions and 0 deletions

View File

@ -870,6 +870,17 @@ int qemu_put_qemu_file(QEMUFile *f_des, QEMUFile *f_src)
return len;
}
/*
* Check if the writable buffer is empty
*/
bool qemu_file_buffer_empty(QEMUFile *file)
{
assert(qemu_file_is_writable(file));
return !file->iovcnt;
}
/*
* Get a string whose length is determined by a single preceding byte
* A preallocated 256 byte buffer must be passed in.

View File

@ -113,6 +113,7 @@ size_t coroutine_mixed_fn qemu_get_buffer_in_place(QEMUFile *f, uint8_t **buf, s
ssize_t qemu_put_compression_data(QEMUFile *f, z_stream *stream,
const uint8_t *p, size_t size);
int qemu_put_qemu_file(QEMUFile *f_des, QEMUFile *f_src);
bool qemu_file_buffer_empty(QEMUFile *file);
/*
* Note that you can only peek continuous bytes from where the current pointer

View File

@ -194,6 +194,8 @@ static CompressResult do_compress_ram_page(QEMUFile *f, z_stream *stream,
uint8_t *p = block->host + offset;
int ret;
assert(qemu_file_buffer_empty(f));
if (buffer_is_zero(p, TARGET_PAGE_SIZE)) {
return RES_ZEROPAGE;
}
@ -208,6 +210,7 @@ static CompressResult do_compress_ram_page(QEMUFile *f, z_stream *stream,
if (ret < 0) {
qemu_file_set_error(migrate_get_current()->to_dst_file, ret);
error_report("compressed data failed!");
qemu_fflush(f);
return RES_NONE;
}
return RES_COMPRESS;
@ -239,6 +242,7 @@ void flush_compressed_data(int (send_queued_data(CompressParam *)))
if (!comp_param[idx].quit) {
CompressParam *param = &comp_param[idx];
send_queued_data(param);
assert(qemu_file_buffer_empty(param->file));
compress_reset_result(param);
}
qemu_mutex_unlock(&comp_param[idx].mutex);
@ -268,6 +272,7 @@ retry:
qemu_mutex_lock(&param->mutex);
param->done = false;
send_queued_data(param);
assert(qemu_file_buffer_empty(param->file));
compress_reset_result(param);
set_compress_params(param, block, offset);

View File

@ -1321,11 +1321,13 @@ static int send_queued_data(CompressParam *param)
assert(block == pss->last_sent_block);
if (param->result == RES_ZEROPAGE) {
assert(qemu_file_buffer_empty(param->file));
len += save_page_header(pss, file, block, offset | RAM_SAVE_FLAG_ZERO);
qemu_put_byte(file, 0);
len += 1;
ram_release_page(block->idstr, offset);
} else if (param->result == RES_COMPRESS) {
assert(!qemu_file_buffer_empty(param->file));
len += save_page_header(pss, file, block,
offset | RAM_SAVE_FLAG_COMPRESS_PAGE);
len += qemu_put_qemu_file(file, param->file);