* Chuan Zheng (zhengch...@huawei.com) wrote:
> From: Zheng Chuan <zhengch...@huawei.com>
>
> Compare hash results for recorded ramblock.
>
> Signed-off-by: Zheng Chuan <zhengch...@huawei.com>
> Signed-off-by: YanYing Zhang <ann.zhuangyany...@huawei.com>
> ---
> migration/dirtyrate.c | 77
> +++++++++++++++++++++++++++++++++++++++++++++++++++
> 1 file changed, 77 insertions(+)
>
> diff --git a/migration/dirtyrate.c b/migration/dirtyrate.c
> index 45cfc91..7badc53 100644
> --- a/migration/dirtyrate.c
> +++ b/migration/dirtyrate.c
> @@ -202,6 +202,83 @@ static int record_block_hash_info(struct
> dirtyrate_config config,
> return 0;
> }
>
> +static int cal_block_dirty_rate(struct block_dirty_info *info)
> +{
> + uint8_t *md = NULL;
> + size_t hash_len;
> + int i;
> + int ret = 0;
> +
> + hash_len = qcrypto_hash_digest_len(QCRYPTO_HASH_ALG_MD5);
> + md = g_new0(uint8_t, hash_len);
Is 'hash_len' actually constant for a given algorithm, like MD5 ?
i.e. can we just have a nice fixed size array?
> + for (i = 0; i < info->sample_pages_count; i++) {
> + ret = get_block_vfn_hash(info, info->sample_page_vfn[i], &md,
> &hash_len);
> + if (ret < 0) {
> + goto out;
> + }
> +
> + if (memcmp(md, info->hash_result + i * hash_len, hash_len) != 0) {
> + info->sample_dirty_count++;
When the page doesn't match, do we have to update info->hash_result with
the new hash? If the page is only modified once, and we catch it on
this cycle, we wouldn't want to catch it next time around.
> + }
> + }
> +
> +out:
> + g_free(md);
> + return ret;
> +}
> +
> +static bool find_block_matched(RAMBlock *block, struct block_dirty_info
> *infos,
> + int count, struct block_dirty_info **matched)
> +{
> + int i;
> +
> + for (i = 0; i < count; i++) {
> + if (!strcmp(infos[i].idstr, qemu_ram_get_idstr(block))) {
> + break;
> + }
> + }
> +
> + if (i == count) {
> + return false;
> + }
> +
> + if (infos[i].block_addr != qemu_ram_get_host_addr(block) ||
> + infos[i].block_pages !=
> + (qemu_ram_get_used_length(block) >> DIRTYRATE_PAGE_SIZE_SHIFT)) {
How does this happen?
> + return false;
> + }
> +
> + *matched = &infos[i];
> + return true;
> +}
> +
> +static int compare_block_hash_info(struct block_dirty_info *info, int
> block_index)
> +{
> + struct block_dirty_info *block_dinfo = NULL;
> + RAMBlock *block = NULL;
> +
> + RAMBLOCK_FOREACH_MIGRATABLE(block) {
> + if (ram_block_skip(block) < 0) {
> + continue;
> + }
> + block_dinfo = NULL;
> + if (!find_block_matched(block, info, block_index + 1, &block_dinfo))
> {
> + continue;
> + }
> + if (cal_block_dirty_rate(block_dinfo) < 0) {
> + return -1;
> + }
> + update_dirtyrate_stat(block_dinfo);
> + }
> + if (!dirty_stat.total_sample_count) {
> + return -1;
> + }
> +
> + return 0;
> +}
> +
> +
> static void calculate_dirtyrate(struct dirtyrate_config config, int64_t time)
> {
> /* todo */
> --
> 1.8.3.1
>
--
Dr. David Alan Gilbert / dgilb...@redhat.com / Manchester, UK
